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Sample records for nendo handotai nano

  1. Site-Directed Mutagenesis of the Nidovirus Replicative Endoribonuclease NendoU Exerts Pleiotropic Effects on the Arterivirus Life Cycle

    PubMed Central

    Posthuma, Clara C.; Nedialkova, Danny D.; Zevenhoven-Dobbe, Jessika C.; Blokhuis, Jeroen H.; Gorbalenya, Alexander E.; Snijder, Eric J.

    2006-01-01

    The highly conserved NendoU replicative domain of nidoviruses (arteriviruses, coronaviruses, and roniviruses) belongs to a small protein family whose cellular branch is prototyped by XendoU, a Xenopus laevis endoribonuclease involved in nucleolar RNA processing. Recently, sequence-specific in vitro endoribonuclease activity was demonstrated for the NendoU-containing nonstructural protein (nsp) 15 of several coronaviruses. To investigate the biological role of this novel enzymatic activity, we have characterized a comprehensive set of arterivirus NendoU mutants. Deleting parts of the NendoU domain from nsp11 of equine arteritis virus was lethal. Site-directed mutagenesis of conserved residues exerted pleiotropic effects. In a first-cycle analysis, replacement of two conserved Asp residues in the C-terminal part of NendoU rendered viral RNA synthesis and virus production undetectable. In contrast, mutagenesis of other conserved residues, including two putative catalytic His residues that are absolutely conserved in NendoU and cellular homologs, produced viable mutants displaying reduced plaque sizes (20 to 80% reduction) and reduced yields of infectious progeny of up to 5 log units. A more detailed analysis of these mutants revealed a moderate reduction in RNA synthesis, with subgenomic RNA synthesis consistently being more strongly affected than genome replication. Our data suggest that the arterivirus nsp11 is a multifunctional protein with a key role in viral RNA synthesis and additional functions in the viral life cycle that are as yet poorly defined. PMID:16439522

  2. Nano Materials

    DTIC Science & Technology

    2007-03-01

    Nano Materials Henne van Heeren enablingMNT Drakensteynlaan 34 3319 RG Dordrecht The Netherlands Henne@enablingMNT.com Introduction... micro sized particles. Nanotubes From a Mancef patent investigation it was learned that carbon nanotechnology (mainly nanotubes, but also...for high purity nanotubes. RTO-EN-AVT-129bis 3 - 1 van Heeren, H. (2007) Nano Materials. In Nanotechnology Aerospace Applications

  3. Nano-technology and nano-toxicology.

    PubMed

    Maynard, Robert L

    2012-01-01

    Rapid developments in nano-technology are likely to confer significant benefits on mankind. But, as with perhaps all new technologies, these benefits are likely to be accompanied by risks, perhaps by new risks. Nano-toxicology is developing in parallel with nano-technology and seeks to define the hazards and risks associated with nano-materials: only when risks have been identified they can be controlled. This article discusses the reasons for concern about the potential effects on health of exposure to nano-materials and relates these to the evidence of the effects on health of the ambient aerosol. A number of hypotheses are proposed and the dangers of adopting unsubstantiated hypotheses are stressed. Nano-toxicology presents many challenges and will need substantial financial support if it is to develop at a rate sufficient to cope with developments in nano-technology.

  4. Nano-technology and nano-toxicology

    PubMed Central

    Maynard, Robert L.

    2012-01-01

    Rapid developments in nano-technology are likely to confer significant benefits on mankind. But, as with perhaps all new technologies, these benefits are likely to be accompanied by risks, perhaps by new risks. Nano-toxicology is developing in parallel with nano-technology and seeks to define the hazards and risks associated with nano-materials: only when risks have been identified they can be controlled. This article discusses the reasons for concern about the potential effects on health of exposure to nano-materials and relates these to the evidence of the effects on health of the ambient aerosol. A number of hypotheses are proposed and the dangers of adopting unsubstantiated hypotheses are stressed. Nano-toxicology presents many challenges and will need substantial financial support if it is to develop at a rate sufficient to cope with developments in nano-technology. PMID:22662021

  5. Sustainable nano-catalysis

    EPA Science Inventory

    A novel nano-catalyst system which bridges the homogenous and heterogeneous system is described that is cheaper, easily accessible (sustainable) and requires no need of catalyst filtration during the work-up. Because of its nano-size, i.e. high surface area, the contact between r...

  6. Nano-composite materials

    DOEpatents

    Lee, Se-Hee; Tracy, C. Edwin; Pitts, J. Roland

    2010-05-25

    Nano-composite materials are disclosed. An exemplary method of producing a nano-composite material may comprise co-sputtering a transition metal and a refractory metal in a reactive atmosphere. The method may also comprise co-depositing a transition metal and a refractory metal composite structure on a substrate. The method may further comprise thermally annealing the deposited transition metal and refractory metal composite structure in a reactive atmosphere.

  7. NanoSail-D

    NASA Technical Reports Server (NTRS)

    Montgomery, Edward E., IV; Adams, Charles L.

    2008-01-01

    The "NanoSail-D" mission is currently scheduled for launch onboard a Falcon-1 Launch Vehicle in the early June 2008 timeframe. The NanoSail-D spacecraft will consist of a solar sail subsystem stowed in a 2U volume and a 1U spacecraft bus, provided by Ames Research Center. The primary objectives of the NanoSail-D technology demonstration mission are to fabricate, stow and deploy on-orbit a solar sail and perform a de-orbit maneuver to demonstrate a potential orbital debris mitigation technology. The NanoSail-D mission is being developed through a collaborative effort between the NASA Marshall Space Flight Center and the NASA Ames Research Center Small Spacecraft Office. Details of the NanoSail-D system will be presented, including: 1) design details of the solar sail reflective membrane quadrants, gossamer booms, deployment system and passive attitude control system, 2) design analysis results including structural, thermal, environmental, orbital debris and safety, and 3) test results including deployment, ascent venting, launch vibration and PPOD integration verification.

  8. Nano-Satellite Avionics

    NASA Technical Reports Server (NTRS)

    Culver, Harry

    1999-01-01

    Abstract NASA's Goddard Space Flight Center (GSFC) is currently developing a new class of satellites called the nano-satellite (nano-sat). A major objective of this development effort is to provide the technology required to enable a constellation of tens to hundreds of nano-satellites to make both remote and in-situ measurements from space. The Nano-sat will be a spacecraft weighing a maximum of 10 kg, including the propellant mass, and producing at least 5 Watts of power to operate the spacecraft. The electronics are required to survive a total radiation dose rate of 100 krads for a mission lifetime of two years. There are many unique challenges that must be met in order to develop the avionics for such a spacecraft. The first challenge is to develop an architecture that will operate on the allotted 5 Watts and meet the diverging requirements of multiple missions. This architecture will need to incorporate a multitude of new advanced microelectronic technologies. The microelectronics developed must be a modular and scalable packaging of technology to solve the problem of developing a solution to both reduce cost and meet the requirements of various missions. This development will utilize the most cost effective approach, whether infusing commercially driven semiconductor devices into spacecraft applications or partnering with industry to design and develop low cost, low power, low mass, and high capacity data processing devices. This paper will discuss the nano-sat architecture and the major technologies that will be developed. The major technologies that will be covered include: (1) Light weight Low Power Electronics Packaging, (2) Radiation Hard/Tolerant, Low Power Processing Platforms, (3) High capacity Low Power Memory Systems (4) Radiation Hard reconfiguragble field programmable gate array (rFPGA)

  9. Nano-rods of zinc oxide in nano-graphene

    NASA Astrophysics Data System (ADS)

    Ortiz, Pedro; Chavira, Elizabeth; Monroy, Marel; Elizalde, José; Santiago, Patricia; Sato, Roberto; Tejeda, Adriana; González, Guillermina; Novelo, Omar; Flores, Carlos

    2014-03-01

    It's of great interest to study the devices based on nano-ZnO and graphene, for their electromagnetic and optical properties to increase the efficiency of solar cells. The graphene multilayers synthesis was done by mechanosynthesis, grinding in a mechanical agate mortar. The zinc oxide nano-rods were synthesized from zinc acetate dihydrate, Ace, (Sigma Aldrich) and ethylene diamine, En, (Sigma Aldrich) with a 1:2 ratio of reagents En/Ace. The ZnO nano-rods in nano-tubes graphene were obtained by mechanosynthesis. The X-ray powder diffraction, shows the shift of C with PDF 12-0212 and ZnO, Zincite PDF 36-1451, both with hexagonal unit cell. The grain size and morphology of graphene (multilayers and nano-tubes), ZnO nano-rods and ZnO-graphene mixture (multilayers, nano-tubes) were observed by scanning electron microscope. Transmission electron microscope, corroborates shown in SEM. Raman spectroscopy, shows the shift of multilayer graphene and the ZnO nano-rods. In photoluminescence measurements, observe the change in intensity in the band defects. Magnetic properties characterization was carried out by Vibrating Sample Magnetometry. We conclude that graphite multilayers dislocated by cutting efforts, forming graphene nano-tubes and encapsulated ZnO nano-rods within graphene.

  10. Biopolymer nano-particles and natural nano-carriers for nano-encapsulation of phenolic compounds.

    PubMed

    Faridi Esfanjani, Afshin; Jafari, Seid Mahdi

    2016-10-01

    Phenolic compounds are major micronutrients in our diet,(1) and evidence for their role in the prevention of degenerative diseases such as cancer, inflammation and neurodegenerative diseases is emerging. The easily destruction against environment stresses and low bioavailability of phenolics are main limitations of their application. Therefore, nano-encapsulated phenolics as a fine delivery system can solve their restrictions. Polymeric nanoparticles and natural nano-carriers are one of the most effective and industrial techniques which can be used for protection and delivery of phenolics. In this review, preparation, application and characterization of polymeric based nano-capsules and natural nano-carriers for phenolics have been considered and discussed including polymeric nanoparticles, polymeric complex nanoparticles, cyclodextrins, nano-caseins, nanocrystals, electrospun nano-fibers, electro-sprayed nano-particles, and nano-spray dried particles. Our main goal was to cover the relevant recent studies in the past few years. Although a number of different types of polymeric and natural based nano-scale delivery systems have been developed, there are relatively poor quantitative understanding of their in vivo absorption, permeation and release. Also, performing toxicity experiments, residual solvent analysis and studying their biological fate during digestion, absorption, and excretion of polymeric nanoparticle and natural nano-carriers containing phenolics should be considered in future researches. In addition, future investigations could focus on application of phenolic nano-scale delivery systems in pharmaceuticals and functional foods.

  11. Nano-energetics Program

    DTIC Science & Technology

    2012-08-09

    NASA Launch First-Ever Test Rocket Fueled by green, Safe Aluminum-Ice Propellant \\.J ••• • ....... AFRI.!I.,; 3DISTRIBUTION A: Approved for public... Propellants & Explosives • Increased Energy Storage • Managed Energy Release • Increased Lethality & Range • Reduced Sensitivity • New Propulsion and...weight graphene sheets) that will eliminate structural catalyst •(2010) First Ever Nano-Aluminum Encapsulated with Ammonium Perchlorade and RDX

  12. Electrospray neutralization process and apparatus for generation of nano-aerosol and nano-structured materials

    SciTech Connect

    Bailey, Charles L.; Morozov, Victor; Vsevolodov, Nikolai N.

    2010-08-17

    The claimed invention describes methods and apparatuses for manufacturing nano-aerosols and nano-structured materials based on the neutralization of charged electrosprayed products with oppositely charged electrosprayed products. Electrosprayed products include molecular ions, nano-clusters and nano-fibers. Nano-aerosols can be generated when neutralization occurs in the gas phase. Neutralization of electrospan nano-fibers with molecular ions and charged nano-clusters may result in the formation of fibrous aerosols or free nano-mats. Nano-mats can also be produced on a suitable substrate, forming efficient nano-filters.

  13. To be nano or not to be nano?

    NASA Astrophysics Data System (ADS)

    Joachim, Christian

    2005-02-01

    Nanomaterials, nanostructures, nanostructured materials, nanoimprint, nanobiotechnology, nanophysics, nanochemistry, radical nanotechnology, nanosciences, nanooptics, nanoelectronics, nanorobotics, nanosoldiers, nanomedecine, nanoeconomy, nanobusiness, nanolawyer, nanoethics to name a few of the nanos. We need a clear definition of all these burgeoning fields for the sake of the grant attribution, for the sake of research program definition, and to avoid everyone being lost in so many nanos.

  14. Magnetic Nano-Materials: Truly Sustainable Green Chemistry Nano Catalysis

    EPA Science Inventory

    We envisioned a novel nano-catalyst system, which can bridge the homogenous and heterogeneous system, and simultaneously be cheaper, easily accessible (sustainable) and possibly does not require elaborate work-up. Because of its nano-size, i.e. high surface area, the contact betw...

  15. PREFACE: Nano- and microfluidics Nano- and microfluidics

    NASA Astrophysics Data System (ADS)

    Jacobs, Karin

    2011-05-01

    The field of nano- and microfluidics emerged at the end of the 1990s parallel to the demand for smaller and smaller containers and channels for chemical, biochemical and medical applications such as blood and DNS analysis [1], gene sequencing or proteomics [2, 3]. Since then, new journals and conferences have been launched and meanwhile, about two decades later, a variety of microfluidic applications are on the market. Briefly, 'the small flow becomes mainstream' [4]. Nevertheless, research in nano- and microfluidics is more than downsizing the spatial dimensions. For liquids on the nanoscale, surface and interface phenomena grow in importance and may even dominate the behavior in some systems. The studies collected in this special issue all concentrate on these type of systems and were part ot the priority programme SPP1164 'Nano- and Microfluidics' of the German Science Foundation (Deutsche Forschungsgemeinschaft, DFG). The priority programme was initiated in 2002 by Hendrik Kuhlmann and myself and was launched in 2004. Friction between a moving liquid and a solid wall may, for instance, play an important role so that the usual assumption of a no-slip boundary condition is no longer valid. Likewise, the dynamic deformations of soft objects like polymers, vesicles or capsules in flow arise from the subtle interplay between the (visco-)elasticity of the object and the viscous stresses in the surrounding fluid and, potentially, the presence of structures confining the flow like channels. Consequently, new theories were developed ( see articles in this issue by Münch and Wagner, Falk and Mecke, Bonthuis et al, Finken et al, Almenar and Rauscher, Straube) and experiments were set up to unambiguously demonstrate deviations from bulk, or 'macro', behavior (see articles in this issue by Wolff et al, Vinogradova and Belyaev, Hahn et al, Seemann et al, Grüner and Huber, Müller-Buschbaum et al, Gutsche et al, Braunmüller et al, Laube et al, Brücker, Nottebrock et al

  16. EDITORIAL: Nano Meets Spectroscopy Nano Meets Spectroscopy

    NASA Astrophysics Data System (ADS)

    Birch, David J. S.

    2012-08-01

    The multidisciplinary two-day Nano Meets Spectroscopy (NMS) event was held at the National Physical Laboratory (NPL), Teddington, UK, in September 2011. The event was planned from the outset to be at the interface of several areas—in particular, spectroscopy and nanoscience, and to bring together topics and people with different approaches to achieving common goals in biomolecular science. Hence the meeting cut across traditional boundaries and brought together researchers using diverse techniques, particularly fluorescence and Raman spectroscopy. Despite engaging common problems, these techniques are frequently seen as mutually exclusive with the two communities rarely interacting at conferences. The meeting was widely seen to have lived up to its billing in good measure. It attracted the maximum capacity of ~120 participants, including 22 distinguished speakers (9 from outside the UK), over 50 posters and a vibrant corporate exhibition comprising 10 leading instrument companies and IOP Publishing. The organizers were Professor David Birch (Chair), Dr Karen Faulds and Professor Duncan Graham of the University of Strathclyde, Professor Cait MacPhee of the University of Edinburgh and Dr Alex Knight of NPL. The event was sponsored by the European Science Foundation, the Institute of Physics, the Royal Society of Chemistry, NPL and the Scottish Universities Physics Alliance. The full programme and abstracts are available at http://sensor.phys.strath.ac.uk/nms/program.php. The programme was quite ambitious in terms of the breadth and depth of scope. The interdisciplinary and synergistic concept of 'X meets Y' played well, cross-fertilization between different fields often being a source of inspiration and progress. Fluorescence and Raman spectroscopy provided the core, but the meeting had little repetition and also attracted contributions on more specialist techniques such as CARS, super-resolution, single molecule and chiral methods. In terms of application the

  17. Dispersive nanoSQUID magnetometry

    NASA Astrophysics Data System (ADS)

    Levenson-Falk, E. M.; Antler, N.; Siddiqi, I.

    2016-11-01

    We describe the theory and implementation of a dispersive magnetometer based on an aluminum nanoSQUID. The nanoSQUID consists of a superconducting loop interrupted by two variable-thickness weak-link nanobridge Josephson junctions. When the nanoSQUID is placed in parallel with a lumped-element capacitor, it acts as the inductive element in a resonant tank circuit. By performing microwave reflectometry on the circuit, the SQUID inductance can be measured, providing a sensitive meter of the flux threading the SQUID loop. In this review we provide the theoretical basis for the device, describe design and operation considerations, and present characterization results on several devices.

  18. Nano-JASMINE: a nano size astrometry satellite

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yukiyasu; Yano, Taihei; Gouda, Naoteru; Yamada, Yoshiyuki; Takato, Naruhisa; Miyazaki, Satoshi; Suganuma, Masahiro; Ueda, Seiji; Nakasuka, Shin'ichi; Jasmine Working Group

    2005-04-01

    We present the outline and current status of the nano-JASMINE project. Nano-JASMINE is a nano size astrometry satellite (the total payload mass is between 1 kg and 10 kg), which is expected to be launched in 2006. The main purpose of the project is to prove and demonstrate the key technologies required for JASMINE (Japanese Astrometry Satellite Mission for Infrared Exploration) in a real space environment Gouda et. al. (2002). Nano-JASMINE will measure annual parallaxes of bright stars (7 mag) with an accuracy greater than 1 milliarcsecond after two years of operation. This is comparable to the accuracy of the Hipparcos catalog. Currently, the subject of major research and development of the project is to build optical and telescope structures using new material, and to establish a data acquisition and control system.

  19. Nano boron nitride flatland.

    PubMed

    Pakdel, Amir; Bando, Yoshio; Golberg, Dmitri

    2014-02-07

    Recent years have witnessed many breakthroughs in research on two-dimensional (2D) nanomaterials, among which is hexagonal boron nitride (h-BN), a layered material with a regular network of BN hexagons. This review provides an insight into the marvellous nano BN flatland, beginning with a concise introduction to BN and its low-dimensional nanostructures, followed by an overview of the past and current state of research on 2D BN nanostructures. A comprehensive review of the structural characteristics and synthetic routes of BN monolayers, multilayers, nanomeshes, nanowaves, nanoflakes, nanosheets and nanoribbons is presented. In addition, electronic, optical, thermal, mechanical, magnetic, piezoelectric, catalytic, ecological, biological and wetting properties, applications and research perspectives for these novel 2D nanomaterials are discussed.

  20. Nano-optomechanical transducer

    DOEpatents

    Rakich, Peter T; El-Kady, Ihab F; Olsson, Roy H; Su, Mehmet Fatih; Reinke, Charles; Camacho, Ryan; Wang, Zheng; Davids, Paul

    2013-12-03

    A nano-optomechanical transducer provides ultrabroadband coherent optomechanical transduction based on Mach-wave emission that uses enhanced photon-phonon coupling efficiencies by low impedance effective phononic medium, both electrostriction and radiation pressure to boost and tailor optomechanical forces, and highly dispersive electromagnetic modes that amplify both electrostriction and radiation pressure. The optomechanical transducer provides a large operating bandwidth and high efficiency while simultaneously having a small size and minimal power consumption, enabling a host of transformative phonon and signal processing capabilities. These capabilities include optomechanical transduction via pulsed phonon emission and up-conversion, broadband stimulated phonon emission and amplification, picosecond pulsed phonon lasers, broadband phononic modulators, and ultrahigh bandwidth true time delay and signal processing technologies.

  1. Nano Engineered Energetic Materials (NEEM)

    DTIC Science & Technology

    2011-01-12

    REPORT Nano Engineered Energetic Materials (NEEM) 14 . ABSTRACT 16. SECURITY CLASSIFICATION OF: The ARO Nano Engineered Energetic Materials (NEEM) MURI...PROPELLANTS EXPLOSIVES PYROTECHNICS 34, 5, 385-393, 2009. 14 . Sabourin, JL; Yetter, RA; Parimi, S, Exploring the Effects of High Surface Area Metal...Energetic Materials, Aberdeen, MD, June 2010, "Fundamental Processes and Properties of Insensitive Energetic Materials". 14 . UIUC group (Dlott

  2. 3D nano-structures for laser nano-manipulation

    PubMed Central

    Seniutinas, Gediminas; Gervinskas, Gediminas; Brasselet, Etienne; Juodkazis, Saulius

    2013-01-01

    Summary The resputtering of gold films from nano-holes defined in a sacrificial PMMA mask, which was made by electron beam lithography, was carried out with a dry plasma etching tool in order to form well-like structures with a high aspect ratio (height/width ≈ 3–4) at the rims of the nano-holes. The extraordinary transmission through the patterns of such nano-wells was investigated experimentally and numerically. By doing numerical simulations of 50-nm and 100-nm diameter polystyrene beads in water and air, we show the potential of such patterns for self-induced back-action (SIBA) trapping. The best trapping conditions were found to be a trapping force of 2 pN/W/μm2 (numerical result) exerted on a 50-nm diameter bead in water. The simulations were based on the analytical Lorentz force model. PMID:24062979

  3. Principles of Nano-Optics

    NASA Astrophysics Data System (ADS)

    Novotny, Lukas; Hecht, Bert

    2006-06-01

    Nano-optics is the study of optical phenomena and techniques on the nanometer scale, that is, near or beyond the diffraction limit of light. It is an emerging field of study, motivated by the rapid advance of nanoscience and nanotechnology which require adequate tools and strategies for fabrication, manipulation and characterization at this scale. In Principles of Nano-Optics the authors provide a comprehensive overview of the theoretical and experimental concepts necessary to understand and work in nano-optics. With a very broad perspective, they cover optical phenomena relevant to the nanoscale across diverse areas ranging from quantum optics to biophysics, introducing and extensively describing all of the significant methods. This is the first textbook specifically on nano-optics. Written for graduate students who want to enter the field, it includes problem sets to reinforce and extend the discussion. It is also a valuable reference for researchers and course teachers. The first nano-optics textbook, it gives a bottom-up description of optical phenomena and techniques encountered in the rapidly expanding fields of nanoscience and nanotechnology Each chapter contains several exercises and problems with hints Numerous high quality illustrations and real-life examples

  4. Plasmon nano-optical tweezers

    NASA Astrophysics Data System (ADS)

    Juan, Mathieu L.; Righini, Maurizio; Quidant, Romain

    2011-06-01

    Conventional optical tweezers, formed at the diffraction-limited focus of a laser beam, have become a powerful and flexible tool for manipulating micrometre-sized objects. Extending optical trapping down to the nanometre scale would open unprecedented opportunities in many fields of science, where such nano-optical tweezers would allow the ultra-accurate positioning of single nano-objects. Among the possible strategies, the ability of metallic nanostructures to control light at the subwavelength scale can be exploited to engineer such nano-optical traps. This Review summarizes the recent advances in the emerging field of plasmon-based optical trapping and discusses the details of plasmon tweezers along with their potential applications to bioscience and quantum optics.

  5. Photovoltaic cell with nano-patterned substrate

    DOEpatents

    Cruz-Campa, Jose Luis; Zhou, Xiaowang; Zubia, David

    2016-10-18

    A photovoltaic solar cell comprises a nano-patterned substrate layer. A plurality of nano-windows are etched into an intermediate substrate layer to form the nano-patterned substrate layer. The nano-patterned substrate layer is positioned between an n-type semiconductor layer composed of an n-type semiconductor material and a p-type semiconductor layer composed of a p-type semiconductor material. Semiconductor material accumulates in the plurality of nano-windows, causing a plurality of heterojunctions to form between the n-type semiconductor layer and the p-type semiconductor layer.

  6. Mechano-micro/nano systems

    NASA Astrophysics Data System (ADS)

    Horie, Mikio

    2004-10-01

    In recent years, the researches about Micro/Nano Systems are down actively in the bio-medical research fields, DNA research fields, chemical analysis systems fields, etc. In the results, a new materials and new functions in the systems are developed. In this invited paper, Mechano-Micro/Nano Systems, especially, motion systems are introduced. First, the research activities concerning the Mechano-Micro/Nano Systems in the world(MST2003, MEMS2003 and MEMS2004) and in Japan(Researech Projects on Nanotechnology and Materials in Ministry of Education, Culture, Sports, Science and Technology) are shown. Secondary, my research activities are introduced. As my research activities, (1) a comb-drive static actuator for the motion convert mechanisms, (2) a micro-nano fabrication method by use of FAB(Fast Atom Beam) machines, (3) a micro optical mirror manipulator for inputs-outputs optical switches, (4) a miniature pantograph mechanism with large-deflective hinges and links made of plastics are discussed and their performances are explained.

  7. Nano copper based high temperature solder alternative

    NASA Astrophysics Data System (ADS)

    Sharma, Akshay

    Nano Cu an alternative to high temperature solder is developed by the Advance Technological Center at the Lockheed Martin Corporation. A printable paste of Cu nano particles is developed with an ability to fuse at 200°C in reflow oven. After reflow the deposited material has nano crystalline and nano porous structure which affects its properties. Accelerated test are performed on nano Cu deposition having nano porous and nano crystalline structure for assessment and prediction of reliability. Nano Cu assemblies with different bond layer thickness are sheared to calculate the strength of the material and are correlated with the porous and crystalline structure of nano Cu. Thermal and isothermal fatigue test are performed on nano Cu to see the dependency of life on stress and further surface of failed assemblies were observed to determine the type of failure. Creep test at RT are performed to find the type of creep mechanism and how they are affected when subjected to high temperature. TEM, SEM, X-ray, C-SAM and optical microscopy is done on the nano Cu sample for structure and surface analysis.

  8. Nano-JASMINE Data Analysis and Publication

    NASA Astrophysics Data System (ADS)

    Yamada, Y.; Hara, T.; Yoshioka, S.; Kobayashi, Y.; Gouda, N.; Miyashita, H.; Hatsutori, Y.; Lammers, U.; Michalik, D.

    2012-09-01

    The core data reduction for the Nano-JASMINE mission is planned to be done with Gaia's Astrometric Global Iterative Solution (AGIS). A collaboration between the Gaia AGIS and Nano-JASMINE teams on the Nano-JASMINE data reduction started in 2007. The Nano-JASMINE team writes codes to generate AGIS input, and this is called Initial Data Treament (IDT). Identification of observed stars and their observed field of view, getting color index, are different from those of Gaia because Nano-JASMINE is ultra small satellite. For converting centroiding results on detector to the celestial sphere, orbit and attitude data of the satellite are used. In Nano-JASMINE, orbit information is derived from on board GPS data and attitude is processed from on-board star sensor data and on-ground Kalman filtering. We also show the Nano-JASMINE goals, status of the data publications and utilizations, and introduce the next Japanese space astrometric mission.

  9. Metallic nano-particles for trapping light.

    PubMed

    Tang, Yongan; Vlahovic, Branislav

    2013-02-07

    We study metallic nano-particles for light trapping by investigating the optical absorption efficiency of the hydrogenated amorphous silicon thin film with and without metallic nano-particles on its top. The size and shape of these nano-particles are investigated as to their roles of light trapping: scattering light to the absorption medium and converting light to surface plasmons. The optical absorption enhancement in the red light region (e.g., 650nm) due to the light trapping of the metallic nano-particles is observed when a layer of metallic nano-particle array has certain structures. The investigation of the light with incident angles shows the importance of the coupling efficiency of light to surface plasmons in the metallic nano-particle light trapping. PACS: 73.20.Mf, 42.25.s, 88.40.hj.

  10. Biologically Inspired Nano-Contact Mechanics

    DTIC Science & Technology

    2009-07-20

    mechanics and micro / nano - fabrication, with potentially significant benefits if we can understand and mimic some of nature’s optimized solutions for...2000) has demonstrated that the micro and nano -scale architectures of the gecko foot fibers are responsible for the animal’s excellent attachment...2. REPORT TYPE Final DATES COVERED (From - To) 01 April 2005-30 Jun 2009 4. TITLE AND SUBTITLE BIOLOGICALLY INSPIRED NANO -CONTACT MECHANICS 5a

  11. New Functional Device using Bio Nano Process

    DTIC Science & Technology

    2011-09-20

    to fabricate new dye-sensitised solar cell , we proposed a new photoresponsive electrode structure using bio nano process. Titanium dioxide ( TiO2 ) has...Abstract] In order to fabricate new dye-sensitised solar cell , we proposed a new photoresponsive electrode structure using bio nano process...Carbon nanotube- TiO2 hybrid materials having multitudious nano-sclae cavities were realized using a bifunctional cage-shaped protein possessing

  12. Nano-Bio Developments in Neuroscience

    NASA Astrophysics Data System (ADS)

    Torimitsu, Keiichi

    Nano-biotechnology (nanobio) is one of the great technological fusions from various different fields. Analysis of biological functions significantly improved because of the recent nanotechnology development. We study this field based on neuroscience. Here we introduce our approach to this field, starting from neural analysis to receptor analysis in order to establish a nano-bio interface. Nano-gap electrode is one of the possible devices for this purpose. Combination of the electrode with receptor protein is investigated.

  13. Cellular-level surgery using nano robots.

    PubMed

    Song, Bo; Yang, Ruiguo; Xi, Ning; Patterson, Kevin Charles; Qu, Chengeng; Lai, King Wai Chiu

    2012-12-01

    The atomic force microscope (AFM) is a popular instrument for studying the nano world. AFM is naturally suitable for imaging living samples and measuring mechanical properties. In this article, we propose a new concept of an AFM-based nano robot that can be applied for cellular-level surgery on living samples. The nano robot has multiple functions of imaging, manipulation, characterizing mechanical properties, and tracking. In addition, the technique of tip functionalization allows the nano robot the ability for precisely delivering a drug locally. Therefore, the nano robot can be used for conducting complicated nano surgery on living samples, such as cells and bacteria. Moreover, to provide a user-friendly interface, the software in this nano robot provides a "videolized" visual feedback for monitoring the dynamic changes on the sample surface. Both the operation of nano surgery and observation of the surgery results can be simultaneously achieved. This nano robot can be easily integrated with extra modules that have the potential applications of characterizing other properties of samples such as local conductance and capacitance.

  14. Nano-Electrochemistry and Nano-Electrografting with an Original Combined AFM-SECM

    PubMed Central

    Ghorbal, Achraf; Grisotto, Federico; Charlier, Julienne; Palacin, Serge; Goyer, Cédric; Demaille, Christophe; Ben Brahim, Ammar

    2013-01-01

    This study demonstrates the advantages of the combination between atomic force microscopy and scanning electrochemical microscopy. The combined technique can perform nano-electrochemical measurements onto agarose surface and nano-electrografting of non-conducting polymers onto conducting surfaces. This work was achieved by manufacturing an original Atomic Force Microscopy-Scanning ElectroChemical Microscopy (AFM-SECM) electrode. The capabilities of the AFM-SECM-electrode were tested with the nano-electrografting of vinylic monomers initiated by aryl diazonium salts. Nano-electrochemical and technical processes were thoroughly described, so as to allow experiments reproducing. A plausible explanation of chemical and electrochemical mechanisms, leading to the nano-grafting process, was reported. This combined technique represents the first step towards improved nano-processes for the nano-electrografting.

  15. Nano-Particles in Cosmic Plasma Environments

    SciTech Connect

    Mann, Ingrid

    2008-09-07

    Astronomical observations and in-situ measurements point to the existence of cosmic nano-particles, but in most cases their material composition and structure are not known. Nano-dust interacts differently than larger dust with the cosmic radiation and plasma environment. Its dynamics and behavior upon collision is not well studied.

  16. Multifunctional carbon nano-paper composite

    NASA Astrophysics Data System (ADS)

    Zhang, Zhichun; Chu, Hetao; Wang, Kuiwen; Liu, Yanjv; Leng, Jinsong

    2013-08-01

    Carbon Nanotube (CNT), for its excellent mechanical, electrical properties and nano size, large special surface physical property, become the most promising material. But carbon nanotube can still fabricated in micro dimension, and can't be made into macro size, so to the carbon nanotube filled composite can't explore the properties of the CNT. Carbon nano-paper is made of pure CNT, with micro pore, and it turn micro sized CNT into macro shaped membrane. Based on the piezo-resistivity and electrical conductivity of the carbon nano-paper, we used the carbon nano-paper as functional layers fabricate functional composite, and studies its strain sensing, composite material deicing and shape memory polymer (SMP) material electric actuation performance. The results shown that the resin can pregnant the nano paper, and there was good bond for nano paper and composite. The functional composite can monitoring the strain with high sensitivity comparing to foil strain gauge. The functional composite can be heated via the carbon nano paper with low power supply and high heating rate. The composite has good deicing and heat actuation performance to composite material. For the good strain sensing, electric conductivity and self-heating character of the carbon nano-paper composite, it can be used for self sensing, anti lightning strike and deicing of composite materials in aircrafts and wind turbine blades.

  17. Nano-fabricated size exclusion chromatograph

    NASA Technical Reports Server (NTRS)

    Svehla, D.; Feldman, S.; Feldman, J.; Grunthaner, F.; Shakkottai, P.; dle Castillo, L.; White, V.

    2002-01-01

    This poster describes the development of a nano-fabricated size exclusion chromatograph (nSEC) based on the principle that molecules traveling through a microcolumn containing nano-fabricated features will have characteristics elution times that directly correlate to molecular weight.

  18. Coloration of cotton fibers using nano chitosan.

    PubMed

    Wijesena, Ruchira N; Tissera, Nadeeka D; de Silva, K M Nalin

    2015-12-10

    A method of coloration of cotton fabrics with nano chitosan is proposed. Nano chitosan were prepared using crab shell chitin nanofibers through alkaline deacetylation process. Average nano fiber diameters of nano chitosan were 18 nm to 35 nm and the lengths were in the range of 0.2-1.3 μm according to the atomic force microscope study. The degree of deacetylation of the material was found to be 97.3%. The prepared nano chitosan dyed using acid blue 25 (2-anthraquinonesulfonic acid) and used as the coloration agent for cotton fibers. Simple wet immersion method was used to color the cotton fabrics by nano chitosan dispersion followed by acid vapor treatment. Scanning electron microscope and atomic force microscope study of the treated cotton fiber revealed that the nano chitosan were consistently deposited on the cotton fiber surface and transformed in to a thin polymer layer upon the acid vapor treatment. The color strength of the dyed fabrics could be changed by changing the concentration of dyed nano chitosan dispersion.

  19. CZT nanoRAIDER_VFG Factsheet

    SciTech Connect

    James, R.; A. E. Bolotnikov; Cui, Yonggang

    2016-01-15

    Brookhaven National Laboratory (BNL) is working with FLIR System Inc., the manufacturer of the nanoRAIDER, to design a handheld device based on a position-sensitive virtual Frisch-grid (VFG) Cadmium-Zinc-Telluride (CdZnTe or CZT) detector array (with 1% or better energy resolution). The new device called nanoRAIDER VFG will be an improvement to the current nanoRAIDER, which is a compact gamma-ray detection instrument manufactured by FLIR Systems Inc. that employs relatively lower-performing CZT hemispheric detectors (i.e., 3%-FWHM CZT detectors). The nanoRAIDER will significantly improve the accuracy while maintaining similar efficiency, as compared to the nanoRAIDER, for in-field analysis of nuclear materials and detection of undeclared activities during inspections conducted by the International Atomic Energy Agency (IAEA). Since the nanoRAIDER is currently used by the IAEA as part of its Complementary Access toolkit, a relatively quick acceptance of the nanoRAIDER VFG for safeguards is anticipated. The nanoRAIDER VFG will help address several items listed in the IAEA’s Long-Term R&D Plan that could enhance the abilities to detect undeclared nuclear material and activities.

  20. Dipole nano-laser: Theory and properties

    SciTech Connect

    Ghannam, T.

    2014-03-31

    In this paper we outline the main quantum properties of the system of nano-based laser called Dipole Nano-Laser emphasizing mainly on its ability to produce coherent light and for different configurations such as different embedding materials and subjecting it to an external classical electric field.

  1. Nano Mechanical Machining Using AFM Probe

    NASA Astrophysics Data System (ADS)

    Mostofa, Md. Golam

    Complex miniaturized components with high form accuracy will play key roles in the future development of many products, as they provide portability, disposability, lower material consumption in production, low power consumption during operation, lower sample requirements for testing, and higher heat transfer due to their very high surface-to-volume ratio. Given the high market demand for such micro and nano featured components, different manufacturing methods have been developed for their fabrication. Some of the common technologies in micro/nano fabrication are photolithography, electron beam lithography, X-ray lithography and other semiconductor processing techniques. Although these methods are capable of fabricating micro/nano structures with a resolution of less than a few nanometers, some of the shortcomings associated with these methods, such as high production costs for customized products, limited material choices, necessitate the development of other fabricating techniques. Micro/nano mechanical machining, such an atomic force microscope (AFM) probe based nano fabrication, has, therefore, been used to overcome some the major restrictions of the traditional processes. This technique removes material from the workpiece by engaging micro/nano size cutting tool (i.e. AFM probe) and is applicable on a wider range of materials compared to the photolithographic process. In spite of the unique benefits of nano mechanical machining, there are also some challenges with this technique, since the scale is reduced, such as size effects, burr formations, chip adhesions, fragility of tools and tool wear. Moreover, AFM based machining does not have any rotational movement, which makes fabrication of 3D features more difficult. Thus, vibration-assisted machining is introduced into AFM probe based nano mechanical machining to overcome the limitations associated with the conventional AFM probe based scratching method. Vibration-assisted machining reduced the cutting forces

  2. Nano-laser on silicon quantum dots

    NASA Astrophysics Data System (ADS)

    Huang, Wei-Qi; Liu, Shi-Rong; Qin, Chao-Jian; Lü, Quan; Xu, Li

    2011-04-01

    A new conception of nano-laser is proposed in which depending on the size of nano-clusters (silicon quantum dots (QD)), the pumping level of laser can be tuned by the quantum confinement (QC) effect, and the population inversion can be formed between the valence band and the localized states in gap produced from the surface bonds of nano-clusters. Here we report the experimental demonstration of nano-laser on silicon quantum dots fabricated by nanosecond pulse laser. The peaks of stimulated emission are observed at 605 nm and 693 nm. Through the micro-cavity of nano-laser, a full width at half maximum of the peak at 693 nm can reach to 0.5 nm. The theoretical model and the experimental results indicate that it is a necessary condition for setting up nano-laser that the smaller size of QD (d < 3 nm) can make the localized states into band gap. The emission energy of nano-laser will be limited in the range of 1.7-2.3 eV generally due to the position of the localized states in gap, which is in good agreement between the experiments and the theory.

  3. Nano-Ceramic Coated Plastics

    NASA Technical Reports Server (NTRS)

    Cho, Junghyun

    2013-01-01

    Plastic products, due to their durability, safety, and low manufacturing cost, are now rapidly replacing cookware items traditionally made of glass and ceramics. Despite this trend, some still prefer relatively expensive and more fragile ceramic/glassware because plastics can deteriorate over time after exposure to foods, which can generate odors, bad appearance, and/or color change. Nano-ceramic coatings can eliminate these drawbacks while still retaining the advantages of the plastic, since the coating only alters the surface of the plastic. The surface coating adds functionality to the plastics such as self-cleaning and disinfectant capabilities that result from a photocatalytic effect of certain ceramic systems. These ceramic coatings can also provide non-stick surfaces and higher temperature capabilities for the base plastics without resorting to ceramic or glass materials. Titanium dioxide (TiO2) and zinc oxide (ZnO) are the candidates for a nano-ceramic coating to deposit on the plastics or plastic films used in cookware and kitchenware. Both are wide-bandgap semiconductors (3.0 to 3.2 eV for TiO2 and 3.2 to 3.3 eV for ZnO), so they exhibit a photocatalytic property under ultraviolet (UV) light. This will lead to decomposition of organic compounds. Decomposed products can be easily washed off by water, so the use of detergents will be minimal. High-crystalline film with large surface area for the reaction is essential to guarantee good photocatalytic performance of these oxides. Low-temperature processing (<100 C) is also a key to generating these ceramic coatings on the plastics. One possible way of processing nanoceramic coatings at low temperatures (< 90 C) is to take advantage of in-situ precipitated nanoparticles and nanostructures grown from aqueous solution. These nanostructures can be tailored to ceramic film formation and the subsequent microstructure development. In addition, the process provides environment- friendly processing because of the

  4. Attostreaking with metallic nano-objects

    NASA Astrophysics Data System (ADS)

    Borisov, A. G.; Echenique, P. M.; Kazansky, A. K.

    2012-02-01

    The application of atto-second streaking spectroscopy (ASS) to direct time-domain studies of the plasmonic excitations in metallic nano-objects is addressed theoretically. The streaking spectrograms for a rectangular gold nano-antenna and spherical gold clusters are obtained within strong field approximation using classical electron trajectory calculations. The results reported here for spherical clusters are also representative of spherical nano-shells. This study demonstrates that ASS allows for detailed characterization of plasmonic modes, including near-field enhancement, frequency and decay rate. The role of the inhomogeneity of the induced electric fields is also demonstrated.

  5. Nano-plasmonic exosome diagnostics.

    PubMed

    Im, Hyungsoon; Shao, Huilin; Weissleder, Ralph; Castro, Cesar M; Lee, Hakho

    2015-06-01

    Exosomes have emerged as a promising biomarker. These vesicles abound in biofluids and harbor molecular constituents from their parent cells, thereby offering a minimally-invasive avenue for molecular analyses. Despite such clinical potential, routine exosomal analysis, particularly the protein assay, remains challenging, due to requirements for large sample volumes and extensive processing. We have been developing miniaturized systems to facilitate clinical exosome studies. These systems can be categorized into two components: microfluidics for sample preparation and analytical tools for protein analyses. In this report, we review a new assay platform, nano-plasmonic exosome, in which sensing is based on surface plasmon resonance to achieve label-free exosome detection. Looking forward, we also discuss some potential challenges and improvements in exosome studies.

  6. Characterization of Integrated Nano Materials

    NASA Astrophysics Data System (ADS)

    Chabli, Amal; Cherns, Peter; Chevalier, Nicolas; Cooper, David; Lafond, Dominique; Bertin, François; Blanc, Henri; Brenac, Ariel; Andreucci, Philippe; Gabriel, Jean-Christophe

    2009-09-01

    Depending on the level of the technological developments, the characterization techniques are mature to support them or still require protocol definition and relevance demonstration for the issues addressed. For Beyond CMOS and Extreme CMOS devices, the integration of nano-objects like nanowires and carbon nanotubes, brings about analysis requirements that are at the frontier of the state-of-the-art characterization techniques. The specific limitations of the use of the existing physical and chemical characterization techniques for integrated nanomaterials are highlighted. In the case of Scanning Probe Microscopy, in-situ localization and positioning are specifically challenging and data analysis is mainly statistical. It is also shown how specific sample preparation may serve the extraction of the required 3D information in particular for Electron Microscopy. The measurement developments related to NEMS technologies guided by the need for dynamic characterization of these components are covered too.

  7. Instrumentation for Nano-porous, Nano-particulate Geopolymeric Materials Research

    DTIC Science & Technology

    2008-11-04

    nano-sized high surface area ceramic powders in geopolymers and geopolymeric composites. On the other hand, the Thinky ARE-250 mixer was purchased to...DATES COVERED (From - To) 6/15/07 - 6/14/08 4. TITLE AND SUBTITLE Instrumentation for Nano-porous, Nano-particulate Geopolymeric Materials... Geopolymers are a new class of ceramic materials which are best understood as rigid inorganic, aluminosilicate, hydrated gels, charge-balanced by cations

  8. Nano-extrusion: a promising tool for continuous manufacturing of solid nano-formulations.

    PubMed

    Baumgartner, Ramona; Eitzlmayr, Andreas; Matsko, Nadejda; Tetyczka, Carolin; Khinast, Johannes; Roblegg, Eva

    2014-12-30

    Since more than 40% of today's drugs have low stability, poor solubility and/or limited ability to cross certain biological barriers, new platform technologies are required to address these challenges. This paper describes a novel continuous process that converts a stabilized aqueous nano-suspension into a solid oral formulation in a single step (i.e., the NANEX process) in order to improve the solubility of a model drug (phenytoin). Phenytoin nano-suspensions were prepared via media milling using different stabilizers. A stable nano-suspension was obtained using Tween(®) 80 as a stabilizer. The matrix material (Soluplus(®)) was gravimetrically fed into the hot melt extruder. The suspension was introduced through a side feeding device and mixed with the molten polymer to immediately devolatilize the water in the nano-suspension. Phenytoin nano-crystals were dispersed and embedded in the molten polymer. Investigation of the nano-extrudates via transmission electron microscopy and atomic force microscopy showed that the nano-crystals were embedded de-aggregated in the extrudates. Furthermore, no changes in the crystallinity (due to the mechanical and thermal stress) occurred. The dissolution studies confirmed that the prepared nano-extrudates increased the solubility of nano-crystalline phenytoin, regardless of the polymer. Our work demonstrates that NANEX represents a promising new platform technology in the design of novel drug delivery systems to improve drug performance.

  9. Indentation analysis of nano-particle using nano-contact mechanics models during nano-manipulation based on atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Daeinabi, Khadijeh; Korayem, Moharam Habibnejad

    2011-03-01

    Atomic force microscopy is applied to measure intermolecular forces and mechanical properties of materials, nano-particle manipulation, surface scanning and imaging with atomic accuracy in the nano-world. During nano-manipulation process, contact forces cause indentation in contact area between nano-particle and tip/substrate which is considerable at nano-scale and affects the nano-manipulation process. Several nano-contact mechanics models such as Hertz, Derjaguin-Muller-Toporov (DMT), Johnson-Kendall-Roberts-Sperling (JKRS), Burnham-Colton-Pollock (BCP), Maugis-Dugdale (MD), Carpick-Ogletree-Salmeron (COS), Pietrement-Troyon (PT), and Sun et al. have been applied as the continuum mechanics approaches at nano-scale. In this article, indentation depth and contact radius between tip and substrate with nano-particle for both spherical and conical tip shape during nano-manipulation process are analyzed and compared by applying theoretical, semiempirical, and empirical nano-contact mechanics models. The effects of adhesion force, as the main contrast point in different nano-contact mechanics models, on nano-manipulation analysis is investigated for different contact radius, and the critical point is discussed for mentioned models.

  10. Nano-Electronics and Bio-Electronics

    NASA Technical Reports Server (NTRS)

    Srivastava, Deepak; Kwak, Dochan (Technical Monitor)

    2001-01-01

    Viewgraph presentation on Nano-Electronics and Bio-Electronics is discussed. Topics discussed include: NASA Ames nanotechnology program, Potential Carbon Nanotube (CNT) application, CNT synthesis,Computational Nanotechnology, and protein nanotubes.

  11. Characterization of Vapor Deposited Nano Structured Membranes

    SciTech Connect

    Jankowski, A; Cherepy, N; Ferreira, J; Hayes, J

    2004-03-25

    The vapor deposition methods of planar magnetron sputtering and electron-beam evaporation are used to synthesize materials with nano structured morphological features that have ultra-high surface areas with continuous open porosity at the nano scale. These nano structured membranes are used in a variety of fuel cells to provide electrode and catalytic functions. Specifically, stand alone and composite nickel electrodes for use in thin film solid-oxide, and molten carbonate fuel cells are formed by sputter deposition and electron bean evaporation, respectively. Also, a potentially high-performance catalyst material for the direct reformation of hydrocarbon fuels at low temperatures is deposited as a nano structure by the reactive sputtering of a copper-zinc alloy using a partial pressure of oxygen at an elevated substrate temperature.

  12. DNA Assembly Line for Nano-Construction

    SciTech Connect

    Oleg Gang

    2009-03-25

    Building on the idea of using DNA to link up nanoparticles scientists at Brookhaven National Lab have designed a molecular assembly line for high-precision nano-construction. Nanofabrication is essential for exploiting the unique properties of nanoparticl

  13. DNA Assembly Line for Nano-Construction

    ScienceCinema

    Oleg Gang

    2016-07-12

    Building on the idea of using DNA to link up nanoparticles scientists at Brookhaven National Lab have designed a molecular assembly line for high-precision nano-construction. Nanofabrication is essential for exploiting the unique properties of nanoparticl

  14. [Nano-safety science for sustainable nanotechnology].

    PubMed

    Yoshioka, Yasuo; Tsutsumi, Yasuo

    2014-01-01

    Recently, it is concerned that nanomaterials induce undesirable biological responses (NanoTox) which is different from conventional materials attributed to their unique physicochemical properties in the world. However, for our enjoying the benefits of nanomateirals, it is most important not to regulate nanomaterials in the blind way but to assure the security of nanomaterials and support the development of nanomaterial industries. These are duty of our country to be advanced country, technology-oriented nation and intellectual property nation. From these viewpoints, we are engaged on not NanoTox study but Nano-safety science study. In this review, we will introduce our Nano-safety science study using mainly silica nanoparticle.

  15. Cirrus Dopant Nano-Composite Coatings

    DTIC Science & Technology

    2014-11-01

    Nickel Phosphorus versus cirrus Zr nano-composite Nickel Phosphorus on Magnesium cirrus wear resistance 590 1025 1,045 0 200 400 600 800...micron duplex Nickel versus cirrus Ti nano- composite Nickel on Mild Steel cirrus corrosion resistance Duplex Ni Cirrus Ti doped Ni 340 430 503 0...100 200 300 400 500 600 HARDNESS (HV) MICROHARDNESS - ELECTROPLATED NICKEL STANDARD DC PLATED DOPED DC PLATED DOPED PULSE PLATED ↑48% 10

  16. Lipid bilayers on nano-templates

    DOEpatents

    Noy, Aleksandr; Artyukhin, Alexander B.; Bakajin, Olgica; Stoeve, Pieter

    2009-08-04

    A lipid bilayer on a nano-template comprising a nanotube or nanowire and a lipid bilayer around the nanotube or nanowire. One embodiment provides a method of fabricating a lipid bilayer on a nano-template comprising the steps of providing a nanotube or nanowire and forming a lipid bilayer around the polymer cushion. One embodiment provides a protein pore in the lipid bilayer. In one embodiment the protein pore is sensitive to specific agents

  17. Nano-fabricated size exclusion chromatograph

    NASA Technical Reports Server (NTRS)

    Svehla, D.; Feldman, S.; Feldman, J.; Grunthaner, F.; Shakkottai, P.; Castillo, L. del; White, V.

    2002-01-01

    This paper describes the development of a nano-fabricated size exclusion chromatograph (nSEC) based on the principle that molecules traveling through amicrocolumn containing nano-fabricated features will have characteristic elution times that directly correlate to molecular weight. Compared to conventional size exclusion chromatography, the nSEC offers greater control over the size exclusion process; mass fabrication; integration of the separation column with associated valves, pumps, and detectors; and dramatic reductions in instrument mass and power requirements.

  18. Nano structural anodes for radiation detectors

    DOEpatents

    Cordaro, Joseph V.; Serkiz, Steven M.; McWhorter, Christopher S.; Sexton, Lindsay T.; Retterer, Scott T.

    2015-07-07

    Anodes for proportional radiation counters and a process of making the anodes is provided. The nano-sized anodes when present within an anode array provide: significantly higher detection efficiencies due to the inherently higher electric field, are amenable to miniaturization, have low power requirements, and exhibit a small electromagnetic field signal. The nano-sized anodes with the incorporation of neutron absorbing elements (e.g., .sup.10B) allow the use of neutron detectors that do not use .sup.3He.

  19. Cancer treatment with nano-diamonds.

    PubMed

    Gupta, Charu; Prakash, Dhan; Gupta, Sneh

    2017-01-01

    Diamond nano-particles find new and far-reaching applications in modern biomedical science and biotechnologies. Due to its excellent biocompatibility, nano-diamonds serve as versatile platforms that can be embedded within polymer-based microfilm devices. Nano-diamonds are complexed with a chemotherapeutic that enables sustained/slow release of the drug for a minimum of one month, with a significant amount of drug in reserve. This opens up the potential for highly localized drug release as a complementary and potent form of treatment with systemic injection towards the reduction of continuous dosing, and as such, attenuation of the often powerful side effects of chemotherapy. Nano-diamonds are quite economical, enabling the broad impact of these devices towards a spectrum of physiological disorders e.g. serving as a local chemotherapeutic patch, or as a pericardial device to suppress inflammation after open heart surgery. Nano-diamond patch could be used to treat a localized region where residual cancer cells might remain after a tumor is removed. Nano-diamonds can be used to explore a broad range of therapeutic classes, including additional small molecules, proteins, therapeutic antibodies, RNAi.

  20. NanoSWARM: A Nano-satellite Mission to Measure Particles and Fields Around the Moon

    NASA Astrophysics Data System (ADS)

    Garrick-Bethell, I.

    2015-12-01

    The NanoSWARM mission concept uses a fleet of cubesats around the Moon to address a number of open problems in planetary science: 1) The mechanisms of space weathering, 2) The origins of planetary magnetism, 3) The origins, distributions, and migration processes of surface water on airless bodies, and 4) The physics of small-scale magnetospheres. To accomplish these goals, NanoSWARM targets scientifically rich features on the Moon known as swirls. Swirls are high-albedo features correlated with strong magnetic fields and low surface-water. NanoSWARM cubesats will make the first near-surface (<1 km altitude) measurements of solar wind flux and magnetic fields at swirls. NanoSWARM cubesats will also perform low-altitude neutron measurements to provide key constraints on the distribution of polar hydrogen concentrations, which are important volatile sinks in the lunar water cycle. To release its cubesats, NanoSWARM uses a high-heritage mother ship in a low altitude, polar, circular orbit. NanoSWARM's results will have direct applications to the geophysics, volatile distribution, and plasma physics of numerous other bodies, in particular asteroids and the terrestrial planets. The technologies and methods used by NanoSWARM will enable many new cubesat missions in the next decade. NanoSWARM was proposed as a NASA Discovery mission in February 2015.

  1. NanoSWARM - A nano-satellite mission to measure particles and fields around the Moon

    NASA Astrophysics Data System (ADS)

    Garrick-Bethell, Ian; Russell, Christopher; Pieters, Carle; Weiss, Benjamin; Halekas, Jasper; Poppe, Andrew; Larson, Davin; Lawrence, David; Elphic, Richard; Hayne, Paul; Blakely, Richard; Kim, Khan-Hyuk; Choi, Young-Jun; Jin, Ho; Hemingway, Doug; Nayak, Michael; Puig-Suari, Jordi; Jaroux, Belgacem; Warwick, Steven

    2015-04-01

    The NanoSWARM mission concept uses a fleet of cubesats around the Moon to address a number of open problems in planetary science: 1) The mechanisms of space weathering, 2) The origins of planetary magnetism, 3) The origins, distributions, and migration processes of surface water on airless bodies, and 4) The physics of small-scale magnetospheres. To accomplish these goals, NanoSWARM targets scientifically rich features on the Moon known as swirls. Swirls are high-albedo features correlated with strong magnetic fields and low surface-water. NanoSWARM cubesats will make the first near-surface (<500 m altitude) measurements of solar wind flux and magnetic fields at swirls. NanoSWARM cubesats will also perform low-altitude neutron measurements to provide key constraints on the distribution of polar hydrogen concentrations, which are important volatile sinks in the lunar water cycle. To release its cubesats, NanoSWARM uses a high-heritage mother ship in a low altitude, polar, circular orbit. NanoSWARM's results will have direct applications to the geophysics, volatile distribution, and plasma physics of numerous other bodies, in particular asteroids and the terrestrial planets. The technologies and methods used by NanoSWARM will enable many new cubesat missions in the next decade, and expand the cubesat paradigm into deep space. NanoSWARM will be proposed as a NASA Discovery mission in early 2015.

  2. Recent patents on nano flavor preparation and its application.

    PubMed

    Feng, Tao; Xiao, Zuobing; Tian, Huaixiang

    2010-11-01

    Nano flavor preparation and its application have been reviewed in this paper. Nano flavor could be prepared by physical methods such as spray drying with microfluidization and ultrasonication, physical adsorption and so on, chemical methods such as complex formation, nano-sized self-structured liquid, and nano emulsification and so on. Different preparation technology could produce nano particles with different physical properties, thus they could be used in different occasions such as food, drug, cosmetics and so on. The article presents some promising patents on nano flavor preparation and its application.

  3. Generation of Nano-Catalyst Particles by Spinodal Nano-Decomposition in Perovskite

    NASA Astrophysics Data System (ADS)

    Kizaki, Hidetoshi; Kusakabe, Koichi; Nogami, Soichiro; Katayama-Yoshida, Hiroshi

    2008-10-01

    A new mechanism of nano-catalyst generation based on the spinodal nano-decomposition in self-regenerating perovskite catalysts for automotive-emissions control is proposed. To demonstrate existence of the spinodal nano-decomposition in real perovskite catalysts, we performed first-principles calculations to evaluate the free energy of La(Fe1-xPdx)O3 and La(Fe1-xRhx)O3. The result indicates appearance of a spinodal region in the phase diagram of each material. Formation of nano-catalyst particles in the perovskite host matrix is crucial for the self-regeneration of perovskite catalyst. Based on the spinodal nano-decomposition model, possible materials are designed for new three-way catalyst with no contents of precious metal.

  4. In Vitro Comparative Skin Irritation Induced by Nano and Non-Nano Zinc Oxide

    PubMed Central

    Vinardell, Maria Pilar; Llanas, Hector; Marics, Laura; Mitjans, Montserrat

    2017-01-01

    This study was designed to determine whether nano-sized ZnO has the potential to cause acute cutaneous irritation using cultured HaCaT keratinocytes and a human skin equivalent as in vitro models, compared to non-nanomaterials. Commercial nano ZnO with different sizes (50 nm and 100 nm) was characterized by dynamic light scattering (DLS) and microscopy (SEM) in different media. Nano ZnO reduced the cell viability of HaCaT in a dose-dependent and time-dependent manner, in a similar way to macro ZnO. However, the 3D-epidermis model revealed no irritation at 1 mg/mL after 24 h of exposure. In conclusion, nano-sized ZnO does not irritate skin, in a similar manner to non-nano ZnO. PMID:28336890

  5. Infrared nano-imaging of plasmonic hotspots on graphene nano-bubbles

    NASA Astrophysics Data System (ADS)

    Fei, Zhe; Foley, Jonathan; Gannett, Will; Zettl, Alex; Liu, Mengkun; Ni, Guangxin; Dai, Siyuan; Keilmann, Fritz; Castro Neto, Antonio; Gray, Stephen; Wiederrecht, Gary; Fogler, Michael; Basov, Dimitri

    2015-03-01

    One of the major goals of plasmonics is to achieve strong enhancement of electromagnetic energy by forming plasmonic hot spots for various applications including bio-sensing, single molecule fingerprinting, surface enhanced spectroscopy, and etc. Here, we demonstrate by infrared nano-imaging that nano-bubbles formed on graphene/hexagonal boron nitride heterostructures are ideal for trapping electromagnetic energy thus forming ultra-confined plasmonic hot spots. The distributions of these hot spots are sensitively dependent on the size and shape of these nano-bubbles as well as the ingredients inside. Further analysis indicates that the observed plasmonic hotspots are formed due to a significant enhancement of the plasmon wavelength and intensity above graphene nano-bubbles filled with air or other low-k dielectric materials. Our work presents a novel scheme for plasmonic hot spots formation and sheds light on future applications of graphene nano-bubbles for plasmon-enhanced single molecule characterization.

  6. Resonant nano-cluster devices.

    PubMed

    Haglmüller, J; Rauter, H; Bauer, G; Pittner, F; Schalkhammer, T

    2005-04-01

    The resonance-enhanced absorption (REA) by metal clusters on a surface is an effective technique on which to base bio-optical devices. A four-layer device consisting of a metal mirror, a polymer or glass-type distance layer, a biomolecule interaction layer and a sub-monolayer of biorecognitively bound metal nano-clusters is reported. Experiments indicate a strong influence of the resonator homogeneity on the absorption maximum. Layer stability plays an important role in the overall performance of the device. Techniques and optimised lab protocols to set up biochips that use the REA process in the detection are presented. The sensors show one to three narrow reflection minima in the visible and or infra-red (IR) part of the spectrum and therefore they do not suffer from the spectral limitations associated with spherical gold colloids. Metal clusters (synthesised by thermal step reduction) as well as metal- dielectric shell clusters (synthesised by various shell deposition processes) are used to precisely shift the readout of the device to any frequency in the visible and near IR range. Disposable single-step protein chips, DNA assays as well as complex biochip arrays are established that use various DNARNA, antigen-antibody and protein-protein interaction systems.

  7. Study on Locally Confined Deposition of Si Nanocrystals in High-Aspect-Ratio Si Nano-Pillar Arrays for Nano-Electronic and Nano-Photonic Applications II

    DTIC Science & Technology

    2010-12-03

    photoluminescence characteristics of equivalent-size controlled silicon quantum dots by employing a nano- porous aluminum oxide membrane as the template for growing...characteristics of the equivalent-size controlled Si-QDs by employing the nano- porous AAO membrane as the template for growing Si-rich SiOx nano-rods...to achieve the spatially confined synthesis of Si-QD. The ultra-bright PL can be emitted from the SiOx nano-rod in nano- porous AAO membrane. In

  8. The Petrography of Meteoritic Nano-Diamonds

    NASA Technical Reports Server (NTRS)

    Dai, Z. R.; Bradley, J. P.; Brownlee, D. E.; Joswiak, D. J.

    2003-01-01

    At least some meteoritic nanodiamonds are likely of presolar origin because of their association with anomalous Xe-HL and Te isotopic components indicative of a supernova (SN) origin. But the abundance of Xe is such that only approx. 1 in 10(exp 6) nano-diamonds contains a Xe atom, and the bulk C-13/C-12 composition of nano-diamond acid residues is chondritic (solar). Therefore, it is possible that a significant fraction of meteoritic nano-diamonds formed within the solar nebula. Nano-diamonds have recently been detected for the first time within the accretion discs of young stars by the Infrared Space Observatory (ISO). No comparable evidence of nanodiamonds in the interstellar medium has yet been found. We have identified nano-diamonds in acid etched thin-sections of meteorites, polar micrometeorites, and interplanetary dust particles (IDPs) with the goal of determining their distribution as a function of heliocentric distance. (It is assumed the meteorites and the polar micrometeorites are from asteroids at 2-4 AU and at least some of the IDPs are from comets at >50AU). We found that nano-diamonds are heterogeneously distributed throughout carbon-rich meteoritic materials (we identified them in some IDPs and not in others), and that their abundance may actually decrease with heliocentric distance, consistent with the hypothesis that some of them formed within the inner solar system and not in a presolar (SN) environment. In order to gain further insight about the origins of meteoritic nano-diamonds we are currently investigating their distribution in unetched thin-sections. We have examined a chondritic cluster IDP (U220GCA), fragments of the Tagish Lake (CM1) meteorite, and a SN graphite spherule (KE3d8) isolated from the Murchison (CM) meteorite. We selected U220GCA because its nano-diamond abundance (in acid etched thin-sections) appears to be as much as approx. 10X higher than in Murchison matrix, Tagish Lake because it has a higher reported nano

  9. Rotation Motion of Designed Nano-Turbine

    PubMed Central

    Li, Jingyuan; Wang, Xiaofeng; Zhao, Lina; Gao, Xingfa; Zhao, Yuliang; Zhou, Ruhong

    2014-01-01

    Construction of nano-devices that can generate controllable unidirectional rotation is an important part of nanotechnology. Here, we design a nano-turbine composed of carbon nanotube and graphene nanoblades, which can be driven by fluid flow. Rotation motion of nano-turbine is quantitatively studied by molecular dynamics simulations on this model system. A robust linear relationship is achieved with this nano-turbine between its rotation rate and the fluid flow velocity spanning two orders of magnitude, and this linear relationship remains intact at various temperatures. More interestingly, a striking difference from its macroscopic counterpart is identified: the rotation rate is much smaller (by a factor of ~15) than that of the macroscopic turbine with the same driving flow. This discrepancy is shown to be related to the disruption of water flow at nanoscale, together with the water slippage at graphene surface and the so-called “dragging effect”. Moreover, counterintuitively, the ratio of “effective” driving flow velocity increases as the flow velocity increases, suggesting that the linear dependence on the flow velocity can be more complicated in nature. These findings may serve as a foundation for the further development of rotary nano-devices and should also be helpful for a better understanding of the biological molecular motors. PMID:25068725

  10. Rotation motion of designed nano-turbine.

    PubMed

    Li, Jingyuan; Wang, Xiaofeng; Zhao, Lina; Gao, Xingfa; Zhao, Yuliang; Zhou, Ruhong

    2014-07-28

    Construction of nano-devices that can generate controllable unidirectional rotation is an important part of nanotechnology. Here, we design a nano-turbine composed of carbon nanotube and graphene nanoblades, which can be driven by fluid flow. Rotation motion of nano-turbine is quantitatively studied by molecular dynamics simulations on this model system. A robust linear relationship is achieved with this nano-turbine between its rotation rate and the fluid flow velocity spanning two orders of magnitude, and this linear relationship remains intact at various temperatures. More interestingly, a striking difference from its macroscopic counterpart is identified: the rotation rate is much smaller (by a factor of ~15) than that of the macroscopic turbine with the same driving flow. This discrepancy is shown to be related to the disruption of water flow at nanoscale, together with the water slippage at graphene surface and the so-called "dragging effect". Moreover, counterintuitively, the ratio of "effective" driving flow velocity increases as the flow velocity increases, suggesting that the linear dependence on the flow velocity can be more complicated in nature. These findings may serve as a foundation for the further development of rotary nano-devices and should also be helpful for a better understanding of the biological molecular motors.

  11. Instrument platforms for nano liquid chromatography.

    PubMed

    Šesták, Jozef; Moravcová, Dana; Kahle, Vladislav

    2015-11-20

    The history of liquid chromatography started more than a century ago and miniaturization and automation are two leading trends in this field. Nanocolumn liquid chromatography (nano LC) and largely synonymous capillary liquid chromatography (capillary LC) are the most recent results of this process where miniaturization of column dimensions and sorbent particle size play crucial role. Very interesting results achieved in the research of extremely miniaturized LC columns at the end of the last century lacked distinctive raison d'être and only advances in mass spectrometry brought a real breakthrough. Configuration of nano LC-electrospray ionization mass spectrometry (LC-ESI-MS) has become a basic tool in bioanalytical chemistry, especially in proteomics. This review discusses and summarizes past and current trends in the realization of nano liquid chromatography (nano LC) platforms. Special attention is given to the mobile phase delivery under nanoflow rates (isocratic, gradient) and sample injection to the nanocolumn. Available detection techniques applied in nano LC separations are also briefly discussed. We followed up the key themes from the original scientific reports over gradual improvements up to the contemporary commercial solutions.

  12. Nano-plasmonic phenomena in graphene

    NASA Astrophysics Data System (ADS)

    Basov, Dimitri

    2014-03-01

    Infrared nano-spectroscopy and nano-imaging experiments have uncovered a rich variety of optical effects associated with the Dirac plasmons of graphene [Fei et al. Nano Lett. 11, 4701 (2011)]. We were able to directly image Dirac plasmons propagating over sub-micron distances [Fei et al. Nature 487, 82 (2012)]. We have succeeded in altering both the amplitude and wavelength of these plasmons by gate voltage in common graphene/SiO2/Si back-gated structures. Scanning plasmon interferometry has allowed us to visualize grain boundaries in CVD graphene. These latter experiments revealed that the grain boundaries tend to form electronic barriers that impede both electrical transport and plasmon propagation. Our results attest to the feasibility of using these electronic barriers to realize tunable plasmon reflectors: a precondition for implementation of various metamaterials concepts [Fei et al. Nature Nano 8, 821 (2013)]. Finally, we have carried out pump-probe experiments interrogating ultra-fast dynamics of plasmons in exfoliated graphene with the nano-scale spatial resolution [Wagner et al. (under review)].

  13. Rotation Motion of Designed Nano-Turbine

    NASA Astrophysics Data System (ADS)

    Li, Jingyuan; Wang, Xiaofeng; Zhao, Lina; Gao, Xingfa; Zhao, Yuliang; Zhou, Ruhong

    2014-07-01

    Construction of nano-devices that can generate controllable unidirectional rotation is an important part of nanotechnology. Here, we design a nano-turbine composed of carbon nanotube and graphene nanoblades, which can be driven by fluid flow. Rotation motion of nano-turbine is quantitatively studied by molecular dynamics simulations on this model system. A robust linear relationship is achieved with this nano-turbine between its rotation rate and the fluid flow velocity spanning two orders of magnitude, and this linear relationship remains intact at various temperatures. More interestingly, a striking difference from its macroscopic counterpart is identified: the rotation rate is much smaller (by a factor of ~15) than that of the macroscopic turbine with the same driving flow. This discrepancy is shown to be related to the disruption of water flow at nanoscale, together with the water slippage at graphene surface and the so-called ``dragging effect''. Moreover, counterintuitively, the ratio of ``effective'' driving flow velocity increases as the flow velocity increases, suggesting that the linear dependence on the flow velocity can be more complicated in nature. These findings may serve as a foundation for the further development of rotary nano-devices and should also be helpful for a better understanding of the biological molecular motors.

  14. Nano-plastics in the aquatic environment.

    PubMed

    Mattsson, K; Hansson, L-A; Cedervall, T

    2015-10-01

    The amount of plastics released to the environment in modern days has increased substantially since the development of modern plastics in the early 1900s. As a result, concerns have been raised by the public about the impact of plastics on nature and on, specifically, aquatic wildlife. Lately, much attention has been paid to macro- and micro-sized plastics and their impact on aquatic organisms. However, micro-sized plastics degrade subsequently into nano-sizes whereas nano-sized particles may be released directly into nature. Such particles have a different impact on aquatic organisms than larger pieces of plastic due to their small size, high surface curvature, and large surface area. This review describes the possible sources of nano-sized plastic, its distribution and behavior in nature, the impact of nano-sized plastic on the well-being of aquatic organisms, and the difference of impact between nano- and micro-sized particles. We also identify research areas which urgently need more attention and suggest experimental methods to obtain useful data.

  15. Morphology and antifungal effect of nano-ZnO and nano-Pd-doped nano-ZnO against Aspergillus and Candida.

    PubMed

    Gondal, Mohammed A; Alzahrani, Alhusain J; Randhawa, Mohammad A; Siddiqui, Mohammad N

    2012-01-01

    The present work was aimed to study the activity of nano-particulated ZnO and nano Pd doped nano-ZnO against Aspergillus and Candida species, commonly contaminating the water supply systems. Micro-ZnO was purchased from the market (Aldrich, USA) while nano ZnO were synthesized using sole gel and precipitation methods and their morphology was determined using XRD and TEM techniques. The average grain size of nano-ZnO estimated by these techniques was 30 nm and 20 nm, respectively. The doping of nano-ZnO with 5 % Pd was achieved by a thermal decomposition method and its morphology; as characterized by XRD, TEM and FESEM techniques; gave an average grain size of 35 nm. Serial dilutions of nano-ZnO doped with 5 % Pd, pure nano-ZnO and micro-ZnO (as a control) were prepared from 10 mg/mL stock solution of each in dermasel agar (OXOID), inoculated with standard strains of Candida albicans and Aspergillus niger and incubated at 37°C for 24 and 48 hours, respectively. Their antimicrobial effect was compared by the minimal inhibitory concentration (MIC), determined as the dilution giving a negligible growth of microorganism. Nano-ZnO doped with 5 % nano-Pd, pure nano-ZnO and micro-ZnO, showed antifungal activity against Aspergilus niger with an MIC of 1.25, 2.5 and 5mg/mL, respectively. However, Candida albicans yeasts were relatively resistant to these compounds, with an MIC of 2.5, 5 and 10 mg/mL for Pd doped nano-ZnO, nano-ZnO and micro-ZnO, respectively. Thus nano-ZnO was twice as potent in killing Aspergillus, as compared to its non-nano-counterpart and loading of nano-ZnO with 5 % nano-Pd further increased its activity, four times that of micro-ZnO. Further investigations are needed to confirm the potential use of nano-ZnO and its doping with nano-Pd in the treatment of water supply systems and food preservation.

  16. Development of nano SiO2 incorporated nano zinc phosphate coatings on mild steel

    NASA Astrophysics Data System (ADS)

    Tamilselvi, M.; Kamaraj, P.; Arthanareeswari, M.; Devikala, S.; Selvi, J. Arockia

    2015-03-01

    This paper reports the development of nano SiO2 incorporated nano zinc phosphate coatings on mild steel at low temperature for achieving better corrosion protection. A new formulation of phosphating bath at low temperature with nano SiO2 was attempted to explore the possibilities of development of nano zinc phosphate coatings on mild steel with improved corrosion resistance. The coatings developed were studied by Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray Spectroscopy (EDX), X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM) and Electrochemical measurements. Significant variation in the coating weight, morphology and corrosion resistance was observed as nano SiO2 concentrations varied from 0.5-4 g/L. The results showed that, the nano SiO2 in the phosphating solution changed the initial potential of the interface between mild steel substrate and phosphating solution and reduce the activation energy of the phosphating process, increase the nucleation sites and yielded zinc phosphate coatings of higher coating weight, greater surface coverage and enhanced corrosion resistance. Better corrosion resistance was observed for coatings derived from phosphating bath containing 1.5 g/L nano SiO2. The new formulation reported in the present study was free from Ni or Mn salts and had very low concentration of sodium nitrite (0.4 g/L) as accelerator.

  17. Colloidal CdTe Nano Crystals Synthesis and Characterization

    DTIC Science & Technology

    2008-09-01

    spectrum of CdTe nano crystals grown at different times.............................3 Figure 3. Luminescence spectrum of CdTe nano crystals after 30 and...500 600 700 800 900 1000 Wavelength in Nanometers Ab so rb an ce 15 Minutes 30 Minutes 45 Minutes 60 Minutes Figure 2. Absorption spectrum of CdTe ...nano crystals grown at different times. The luminescence spectrum of the CdTe nano crystals synthesized 30 minutes and 45 minutes after injection of

  18. Nano-donuts on metal surfaces

    NASA Astrophysics Data System (ADS)

    Rai, Abhishek; Nayak, Jayita; Roy Barman, Sudipta

    2015-03-01

    Nano-structures comprising of a pit surrounded by a circular ridge that resemble nano-donuts have been observed on flat terraces of both Au(1 1 1) and Al(1 0 0) surfaces after low energy (1.5-2 keV) rare gas (rg) ion implantation. From time lapse scanning tunneling microscopy, we demonstrate that these donuts originate from the rg bubbles that migrate out from the sub-surface region. The circular shape of the donuts is observed for both Ar and Ne bubbles. The donuts and the related nano-structures represent different stages of large time scale co-operative relaxation of Au atoms by long range elastic interaction after the rg bubbles leave the metal.

  19. Modelling nano-clusters and nucleation.

    PubMed

    Catlow, C Richard A; Bromley, Stefan T; Hamad, Said; Mora-Fonz, Miguel; Sokol, Alexey A; Woodley, Scott M

    2010-01-28

    We review the growing role of computational techniques in modelling the structures and properties of nano-particulate oxides and sulphides. We describe the main methods employed, including those based on both electronic structure and interatomic potential approaches. Particular attention is paid to the techniques used in searching for global minima in the energy landscape defined by the nano-particle cluster. We summarise applications to the widely studied ZnO and ZnS systems, to silica nanochemistry and to group IV oxides including TiO(2). We also consider the special case of silica cluster chemistry in solution and its importance in understanding the hydrothermal synthesis of microporous materials. The work summarised, together with related experimental studies, demonstrates a rich and varied nano-cluster chemistry for these materials.

  20. Micro and Nano Systems for Space Exploration

    NASA Technical Reports Server (NTRS)

    Manohara, Harish

    2007-01-01

    This slide presentation reviews the use of micro and nano systems in Space exploration. Included are: an explanation of the rationales behind nano and micro technologies for space exploration, a review of how the devices are fabricated, including details on lithography with more information on Electron Beam (E-Beam) lithography, and X-ray lithography, a review of micro gyroscopes and inchworm Microactuator as examples of the use of MicroElectoMechanical (MEMS) technology. Also included is information on Carbon Nanotubes, including a review of the CVD growth process. These micro-nano systems have given rise to the next generation of miniature X-ray Diffraction, X-ray Fluorescence instruments, mass spectrometers, and terahertz frequency vacuum tube oscillators and amplifiers, scanning electron microscopes and energy dispersive x-ray spectroscope. The nanotechnology has also given rise to coating technology, such as silicon nanotip anti-reflection coating.

  1. Epigenetic effects of nano-sized materials.

    PubMed

    Stoccoro, Andrea; Karlsson, Hanna L; Coppedè, Fabio; Migliore, Lucia

    2013-11-08

    The term epigenetics includes several phenomena such as DNA methylation, histone tail modifications, and microRNA mediated mechanisms, which are able to mold the chromatin structure and/or gene expression levels, without altering the primary DNA sequence. Environmental agents can exert epigenetic properties and there is increasing evidence of epigenetic deregulation of gene expression in several human diseases, including cancer, cardiovascular diseases, autism spectrum disorders, autoimmune diseases, and neurodegeneration, among others. Given the widespread use and dispersion in the environment of nano-sized materials, this article summarizes the studies performed so far to evaluate their potential epigenetic properties. Those studies highlight the ability of certain nano-sized compounds to induce an impaired expression of genes involved in DNA methylation reactions leading to global DNA methylation changes, as well as changes of gene specific methylation of tumor suppressor genes, inflammatory genes, and DNA repair genes, all potentially involved in cancer development. Moreover, some nano-sized compounds are able to induce changes in the acetylation and methylation of histone tails, as well as microRNA deregulated expression. We also provided a detailed description of currently available methodologies to evaluate epigenetic modifications. Standard protocols are currently available to evaluate cytotoxic and genotoxic effects of nano-sized materials. By contrast, there are at present no available standard protocols to evaluate the epigenetic potential of any given compound. The currently available methodologies offer different, but often complementary information to characterize potential epigenetic changes induced by exposure to nano-sized compounds. Given the widespread use and dispersion in the environment of nano-sized materials, at present and foreseeable in the near future, and in light of the indication of potential epigenetic properties here reviewed, more

  2. Construction of coherent nano quantitative structure-properties relationships (nano-QSPR) models and catastrophe theory.

    PubMed

    Carbó-Dorca, R; Besalú, E

    2011-10-01

    The structure one can associate to coherent nano-quantitative structure-properties relationship (nano-QSPR) models is briefly discussed. Such nano-QSPR model functions are described as possessing three parts: a particle size polynomial; a typical QSPR function; and a special effects function. The expected behaviour of the particle size part is discussed from the point of view of catastrophe theory, in this way providing a plausible general picture about the emergence of new properties of nanoparticles and holographic location of information content.

  3. Active control of nano dimers response using piezoelectric effect

    NASA Astrophysics Data System (ADS)

    Mekkawy, Ahmed A.; Ali, Tamer A.; Badawi, Ashraf H.

    2016-09-01

    Nano devices can be used as building blocks for Internet of Nano-Things network devices, such as sensors/actuators, transceivers, and routers. Although nano particles response can be engineered to fit in different regimes, for such a nano particle to be used as an active nano device, its properties should be dynamically controlled. This controllability is a challenge, and there are many proposed techniques to tune nanoparticle response on the spot through a sort of control signal, wither that signal is optical (for all-optical systems) or electronic (for opto-electronic systems). This will allow the use of nano particles as nano-switches or as dynamic sensors that can pick different frequencies depending on surrounding conditions or depending on a smart decisions. In this work, we propose a piezoelectric substrate as an active control mediator to control plasmonic gaps in nano dimers. This method allows for integrating nano devices with regular electronics while communicating control signals to nano devices through applying electric signals to a piezoelectric material, in order to control the gaps between nano particles in a nano cluster. We do a full numerical study to the system, analyzing the piezoelectric control resolution (minimum gap change step) and its effect on a nanodimer response as a nanoantenna. This analysis considers the dielectric functions of materials within the visible frequencies range. The effects of different parameters, such as the piezoelectric geometrical structure and materials, on the gap control resolution and the operating frequency are studied.

  4. Three-Dimensional Nano-Lithography for Emerging Technologies

    DTIC Science & Technology

    2005-09-27

    SUBJECT TERMS Grayscale lithography, micro - and nano -fabrication, 3D micro ...meso-optics for optical system integration, and the burgeoning field of micro -electro-mechanical systems (MEMS), provide drive in the micro - and nano ...scientific literature, and presentations at conferences devoted to micro - and nano -fabrication and micro - optics. More importantly, we developed technology

  5. Electrokinetics Models for Micro and Nano Fluidic Impedance Sensors

    DTIC Science & Technology

    2010-11-01

    1 ELECTROKINETICS MODELS FOR MICRO AND NANO FLUIDIC IMPEDANCE SENSORS Yi Wang*, Hongjun Song, Ketan Bhatt, Kapil Pant CFD Research Corporation...analysis, design, and protocol development of novel micro - and nano - fluidics based impedance sensors. 1. INTRODUCTION Exposure to toxic...electrokinetic transport process at the micro - and nano -scale and to interrogate the sensor performance subject to the variations in design

  6. Catalytic wateroxidation on derivatized nanoITO

    SciTech Connect

    Chen, Zuofeng; Concepcion, Javier J; Hull, Jonathan F; Hoertz, Paul G.; Meyer, Thomas J.

    2010-06-22

    Electrocatalytic water oxidation occurs on high surface area, nanocrystalline ITO (nanoITO) surface-derivatized by phosphonate-binding of the catalyst [Ru(Mebimpy)(4,4'-((HO)2OPCH2)2bpy)(OH2)]2+ (Mebimpy is 2,6-bis(1-methylbenzimidazol-2-yl)pyridine; bpy is 2,2'-bipyridine). With nanoITO, spectral data can be acquired on electrochemically generated intermediates and voltammograms monitored spectrophotometrically.

  7. Nano polypeptide particles reinforced polymer composite fibers.

    PubMed

    Li, Jiashen; Li, Yi; Zhang, Jing; Li, Gang; Liu, Xuan; Li, Zhi; Liu, Xuqing; Han, Yanxia; Zhao, Zheng

    2015-02-25

    Because of the intensified competition of land resources for growing food and natural textile fibers, there is an urgent need to reuse and recycle the consumed/wasted natural fibers as regenerated green materials. Although polypeptide was extracted from wool by alkaline hydrolysis, the size of the polypeptide fragments could be reduced to nanoscale. The wool polypeptide particles were fragile and could be crushed down to nano size again and dispersed evenly among polymer matrix under melt extrusion condition. The nano polypeptide particles could reinforce antiultraviolet capability, moisture regain, and mechanical properties of the polymer-polypeptide composite fibers.

  8. Nano-material and method of fabrication

    SciTech Connect

    Menchhofer, Paul A; Seals, Roland D; Howe, Jane Y; Wang, Wei

    2015-02-03

    A fluffy nano-material and method of manufacture are described. At 2000.times. magnification the fluffy nanomaterial has the appearance of raw, uncarded wool, with individual fiber lengths ranging from approximately four microns to twenty microns. Powder-based nanocatalysts are dispersed in the fluffy nanomaterial. The production of fluffy nanomaterial typically involves flowing about 125 cc/min of organic vapor at a pressure of about 400 torr over powder-based nano-catalysts for a period of time that may range from approximately thirty minutes to twenty-four hours.

  9. Desensitizing nano powders to electrostatic discharge ignition

    SciTech Connect

    Steelman, Ryan; Clark, Billy; Pantoya, Michelle L.; Heaps, Ronald J.; Daniels, Michael A.

    2015-08-01

    Electrostatic discharge (ESD) is a main cause for ignition in powder media ranging from grain silos to fireworks. Nanoscale particles are orders of magnitude more ESD ignition sensitive than their micron scale counterparts. This study shows that at least 13 vol. % carbon nanotubes (CNT) added to nano-aluminum and nano-copper oxide particles (nAl + CuO) eliminates ESD ignition sensitivity. The CNT act as a conduit for electric energy and directs electric charge through the powder to desensitize the reactive mixture to ignition. For nanoparticles, the required CNT concentration for desensitizing ESD ignition acts as a diluent to quench energy propagation.

  10. Report of International NanoSPD Steering Committee and statistics on recent NanoSPD activities

    NASA Astrophysics Data System (ADS)

    2014-08-01

    Abstract. The Université de Lorraine in Metz, France, is the selected site for the 6th International Conference on Nanomaterials by Severe Plastic Deformation (NanoSPD6) following a series of five earlier conferences. This introductory paper reports on several major developments in NanoSPD activities as well as on very recent NanoSPD citation data which confirm the continued growth and expansion of this important research area. Close attention is given to the topics of workshops, conferences and seminars organized during these last three years as well as on books and reviews published prior to the NanoSPD6 conference. A special concern of the committee is in introducing and discussing the appropriate terminology to be applied in this new field of materials science and engineering.

  11. Plasmonic graded nano-disks as nano-optical conveyor belt.

    PubMed

    Kang, Zhiwen; Lu, Haifei; Chen, Jiajie; Chen, Kun; Xu, Fang; Ho, Ho-Pui

    2014-08-11

    We propose a plasmonic system consisting of nano-disks (NDs) with graded diameters for the realization of nano-optical conveyor belt. The system contains a couple of NDs with individual elements coded with different resonant wavelengths. By sequentially switching the wavelength and polarization of the excitation source, optically trapped target nano-particle can be transferred from one ND to another. The feasibility of such function is verified based on the three-dimensional finite-difference time-domain technique and the Maxwell stress tensor method. Our design may provide an alternative way to construct nano-optical conveyor belt with which target molecules can be delivered between trapping sites, thus enabling many on-chip optofluidic applications.

  12. Nano-manipulation of diamond-based single photon sources.

    PubMed

    Ampem-Lassen, E; Simpson, D A; Gibson, B C; Trpkovski, S; Hossain, F M; Huntington, S T; Ganesan, K; Hollenberg, L C L; Prawer, S

    2009-07-06

    The ability to manipulate nano-particles at the nano-scale is critical for the development of active quantum systems. This paper presents a technique to manipulate diamond nano-crystals at the nano-scale using a scanning electron microscope, nano-manipulator and custom tapered optical fibre probes. The manipulation of a approximately 300 nm diamond crystal, containing a single nitrogen-vacancy centre, onto the endface of an optical fibre is demonstrated. The emission properties of the single photon source post manipulation are in excellent agreement with those observed on the original substrate.

  13. Every which way – nanos gene regulation in echinoderms

    PubMed Central

    Oulhen, Nathalie; Wessel, Gary M.

    2014-01-01

    Nanos is an essential factor of germ line success in all animals tested. This gene encodes a Zn-finger RNA-binding protein that in complex with its partner pumilio, binds to and changes the fate of several known transcripts. We summarize here the documented functions of nanos in several key organisms, and then emphasize echinoderms as a working model for how nanos expression is regulated. Nanos presence outside of the target cells is often detrimental to the animal, and in sea urchins, nanos expression appears to be regulated at every step of transcription, and post-transcriptional activity, making this gene product exciting, every which way. PMID:24376110

  14. Every which way--nanos gene regulation in echinoderms.

    PubMed

    Oulhen, Nathalie; Wessel, Gary M

    2014-03-01

    Nanos is an essential factor of germ line success in all animals tested. This gene encodes a Zn-finger RNA-binding protein that in complex with its partner pumilio binds to and changes the fate of several known transcripts. We summarize here the documented functions of Nanos in several key organisms, and then emphasize echinoderms as a working model for how nanos expression is regulated. Nanos presence outside of the target cells is often detrimental to the animal, and in sea urchins, nanos expression appears to be regulated at every step of transcription, and post-transcriptional activity, making this gene product exciting, every which way.

  15. Nano-Drugs Based on Nano Sterically Stabilized Liposomes for the Treatment of Inflammatory Neurodegenerative Diseases

    PubMed Central

    Turjeman, Keren; Bavli, Yaelle; Kizelsztein, Pablo; Schilt, Yaelle; Allon, Nahum; Katzir, Tamar Blumenfeld; Sasson, Efrat; Raviv, Uri; Ovadia, Haim; Barenholz, Yechezkel

    2015-01-01

    The present study shows the advantages of liposome-based nano-drugs as a novel strategy of delivering active pharmaceutical ingredients for treatment of neurodegenerative diseases that involve neuroinflammation. We used the most common animal model for multiple sclerosis (MS), mice experimental autoimmune encephalomyelitis (EAE). The main challenges to overcome are the drugs’ unfavorable pharmacokinetics and biodistribution, which result in inadequate therapeutic efficacy and in drug toxicity (due to high and repeated dosage). We designed two different liposomal nano-drugs, i.e., nano sterically stabilized liposomes (NSSL), remote loaded with: (a) a “water-soluble” amphipathic weak acid glucocorticosteroid prodrug, methylprednisolone hemisuccinate (MPS) or (b) the amphipathic weak base nitroxide, Tempamine (TMN). For the NSSL-MPS we also compared the effect of passive targeting alone and of active targeting based on short peptide fragments of ApoE or of β-amyloid. Our results clearly show that for NSSL-MPS, active targeting is not superior to passive targeting. For the NSSL-MPS and the NSSL-TMN it was demonstrated that these nano-drugs ameliorate the clinical signs and the pathology of EAE. We have further investigated the MPS nano-drug’s therapeutic efficacy and its mechanism of action in both the acute and the adoptive transfer EAE models, as well as optimizing the perfomance of the TMN nano-drug. The highly efficacious anti-inflammatory therapeutic feature of these two nano-drugs meets the criteria of disease-modifying drugs and supports further development and evaluation of these nano-drugs as potential therapeutic agents for diseases with an inflammatory component. PMID:26147975

  16. Instrumentation for Nano-porous, Nano-particulate Geopolymeric Materials Research

    DTIC Science & Technology

    2008-11-04

    surface area ceramic powders in geopolymers and geopolymeric composites. On the other hand, the Thinky ARE-250 mixer was purchased to assist with...3. DATES COVERED (From - To) 6/15/07 – 6/14/08 4. TITLE AND SUBTITLE Instrumentation for Nano-porous, Nano-particulate Geopolymeric ...STATEMENT 13. SUPPLEMENTARY NOTES 14. ABSTRACT -- Geopolymers are a new class of ceramic materials which are best understood as rigid

  17. We Scream for Nano Ice Cream

    ERIC Educational Resources Information Center

    Jones, M. Gail; Krebs, Denise L.; Banks, Alton J.

    2011-01-01

    There is a wide range of new products emerging from nanotechnology, and "nano ice cream" is an easy one that you can use to teach topics from surface area to volume applications. In this activity, students learn how ice cream can be made smoother and creamier tasting through nanoscience. By using liquid nitrogen to cool the cream mixture, students…

  18. Superhydrophobic Behavior on Nano-structured Surfaces

    NASA Astrophysics Data System (ADS)

    Schaeffer, Daniel

    2008-05-01

    Superhydrophobic behavior is observed in natural occurrences and has been thoroughly studied over the past few years. Water repellant properties on uniform arrays of vertically aligned nano-cones were investigated to determine the highest achievable contact angle (a measure of water drop repellency), which is measured from the reference plane on which the water drop sits to the tangent line of the point at which the drop makes contact with the reference plane. At low aspect ratios (height vs. width of the nano-cones), surface tension pulls the water into the nano-cone array, resulting in a wetted surface. Higher aspect ratios reverse the effect of the surface tension, resulting in a larger contact angle that causes water drops to roll off the surface. Fiber drawing, bundling, and redrawing are used to produce the structured array glass composite surface. Triple-drawn fibers are fused together, annealed, and sliced into thin wafers. The surface of the composite glass is etched to form nano-cones through a differential etching process and then coated with a fluorinated self-assembled monolayer (SAM). Cone aspect ratios can be varied through changes in the chemistry and concentration of the etching acid solution. Superhydrophobic behavior occurs at contact angles >150 and it is predicted and measured that optimal behavior is achieved when the aspect ratio is 4:1, which displays contact angles >=175 .

  19. Quantifying the properties of nano-composites.

    NASA Astrophysics Data System (ADS)

    Daw, Murray; Zhang, Bo; He, Jian; Tritt, Terry

    2008-03-01

    With the proliferation of nano-composites produced for possible thermoelectric application, we ask the question: To what extent is a given nano-composite like other composites? Or, in other words, when do we know that we have something new? To address this we apply the classical theory of composites to specific nano-composites grown and characterized at Clemson. The theory is very simple and assumes explicitly very simple properties of the materials, the most important being Fourier's Law/Ohm's Law. Given this assumption, the theory of composites can be applied to the nano-composites based on what is known of the microstructure. This ``classical'' result then forms the basis by which the properties can be compared to determine if non-classical effects are being observed. One simple theory is the application of rigorous bounds, such as the Hashin-Strikman Bounds which are based only on very simple microstructural descriptors. Another simple theory is the application of FEM, which can be constructed directly from SEM images of the samples using the NIST code ``OOF''. The FEM produces specific predictions for the composite properties. We find that the Hashin-Strikman Bounds are very useful for analyzing the thermal conductivities of composites, but are too loose to be useful for low-temperature electrical conductivity of composites composed of metals and insulators, where the FEM technique can be applied successfully.

  20. Synthesis and characterization of struvite nano particles

    NASA Astrophysics Data System (ADS)

    Rathod, K. R.; Jogiya, B. V.; Chauhan, C. K.; Joshi, M. J.

    2015-06-01

    Struvite, Ammonium Magnesium Phosphate Hexahydrate [(AMPH) - (NH4)MgPO4.6(H2O)], is one of the fascinating inorganic phosphate minerals. Struvite is one of the components of the urinary stones. Struvite occurs as crystallites in urine and grows as a type of kidney stone. In this study, struvite nano particles were synthesized by wet chemical technique. The aqueous solutions containing dissolved Mg(CH3COO)2.4H2O and (NH4)H2PO4 mixed at the Mg/P molar ratio of 1.00. The synthesized struvite nano particles were characterized by XRD, FT-IR, Thermal Analysis and TEM. From XRD, crystal structure of the nano particle was found to be orthorhombic and crystalline size was found to be within 11 to 26 nm. The FT-IR spectrum for the struvite nano particles confirmed the presence of a water molecule and metal-oxygen stretching vibration, O-H stretching and bending, N-H bending and stretching, P-O bending and stretching vibrations. The Thermal Analysis was carried out from room temperature to 900°C. From TEM analysis, particle size was 23 to 30 nm. All the results were compared with bulk struvite.

  1. Optical properties of silver nano-cubes

    NASA Astrophysics Data System (ADS)

    Das, Ratan; Sarkar, Sumit

    2015-10-01

    Here in this work we are interested in the optical properties of uniform sized cubic silver nano-crystals. These silver nano-crystals are prepared by simple chemical reduction method using PVP as a capping agent. High Resolution Transmission Electron Microscopy (HRTEM) images and X-ray diffraction (XRD) analysis reveal that the produced nano-crystals are FCC in structure with a cubic morphology having an average size of 100 nm approximately. Further High Performance Liquid Chromatography (HPLC) study reveals the monodispersity of the prepared sample. UV/Vis study shows an absorption peak due to surface plasmon resonance (SPR) in the visible range which remains steady for more than two months and after that absorption peak position gets red shifted slowly as samples becomes more aged, confirming the agglomeration after two months. Most important optical property shown by the sample is the photoluminescence (PL), which gives an emission spectra in the visible range, confirming a band gap in the silver nano-cubes. It has been observed that the different PL spectra show an emission peak at 482 nm with different intensity for different excitation wavelength.

  2. Optical piezoelectric transducer for nano-ultrasonics.

    PubMed

    Lin, Kung-Hsuan; Chern, Gia-Wei; Yu, Cheng-Ta; Liu, Tzu-Ming; Pan, Chang-Chi; Chen, Guan-Ting; Chyi, Jen-Inn; Huang, Sheng-Wen; Li, Pai-Chi; Sun, Chi-Kuang

    2005-08-01

    Piezoelectric semiconductor strained layers can be treated as piezoelectric transducers to generate nanometer-wavelength and THz-frequency acoustic waves. The mechanism of nano-acoustic wave (NAW) generation in strained piezoelectric layers, induced by femtosecond optical pulses, can be modeled by a macroscopic elastic continuum theory. The optical absorption change of the strained layers modulated by NAW through quantum-confined Franz-Keldysh (QCFK) effects allows optical detection of the propagating NAW. Based on these piezoelectric-based optical principles, we have designed an optical piezoelectric transducer (OPT) to generate NAW. The optically generated NAW is then applied to one-dimensional (1-D) ultrasonic scan for thickness measurement, which is the first step toward multidimensional nano-ultrasonic imaging. By launching a NAW pulse and resolving the returned acoustic echo signal with femtosecond optical pulses, the thickness of the studied layer can be measured with <1 nm resolution. This nano-structured OPT technique will provide the key toward the realization of nano-ultrasonics, which is analogous to the typical ultrasonic techniques but in a nanometer scale.

  3. Green Chemistry by Nano-Catalysis

    EPA Science Inventory

    The approach of using MW technique with nano-catalysis and benign aqueous reaction medium can offer an extraordinary synergistic effect with greater potential than these three individual components in isolation. To illustrate the ‘‘proof-of-concept’’ of this “Green and Sustainabl...

  4. Transferring metallic nano-island on hydrogen passivated silicon surface for nano-electronics

    NASA Astrophysics Data System (ADS)

    Deng, J.; Troadec, C.; Joachim, C.

    2009-11-01

    In a planar configuration, precise positioning of ultra-flat metallic nano-islands on semiconductor surface opens a way to construct nanostructures for atomic scale interconnects. Regular triangular Au nano-islands have been grown on atomically flat MoS2 substrates and manipulated by STM to form nanometer gap metal-pads connector for single molecule electronics study. The direct assembly of regular shaped metal nano-islands on H-Si(100) is not achievable. Here we present how to transfer Au triangle nano-islands from MoS2 onto H-Si(100) in a clean manner. In this experiment, clean MoS2 substrates are patterned as array of MoS2 pillars with height of 8 μm. The Au triangle nano-islands are grown on top of the pillars. Successful printing transfer of these Au nano-islands from the MoS2 pillars to the H-Si(100) is demonstrated.

  5. Sub-diffraction nano manipulation using STED AFM.

    PubMed

    Chacko, Jenu Varghese; Canale, Claudio; Harke, Benjamin; Diaspro, Alberto

    2013-01-01

    In the last two decades, nano manipulation has been recognized as a potential tool of scientific interest especially in nanotechnology and nano-robotics. Contemporary optical microscopy (super resolution) techniques have also reached the nanometer scale resolution to visualize this and hence a combination of super resolution aided nano manipulation ineluctably gives a new perspective to the scenario. Here we demonstrate how specificity and rapid determination of structures provided by stimulated emission depletion (STED) microscope can aid another microscopic tool with capability of mechanical manoeuvring, like an atomic force microscope (AFM) to get topological information or to target nano scaled materials. We also give proof of principle on how high-resolution real time visualization can improve nano manipulation capability within a dense sample, and how STED-AFM is an optimal combination for this job. With these evidences, this article points to future precise nano dissections and maybe even to a nano-snooker game with an AFM tip and fluorospheres.

  6. Investigating the optical XNOR gate using plasmonic nano-rods

    NASA Astrophysics Data System (ADS)

    Akhlaghi, Majid; Kaboli, Milad

    2016-04-01

    In this paper, a coherent perfect absorption (CPA)-type XNOR gate based on plasmonic nano particle is proposed. It consists of two plasmonic nano rod arrays on top of two parallel arms with quartz substrate. The operation principle is based on the absorbable formation of a conductive path in the dielectric layer of a plasmonic nano-particles waveguide. Since the CPA efficiency depends strongly on the number of plasmonic nano-rod and the nano rod location, an efficient binary optimization method based the Particle Swarm Optimization (PSO) algorithm is used to design an optimized array of the plasmonic nano-rod in order to achieve the maximum absorption coefficient in the 'off' state and the minimum absorption coefficient in the 'on' state. In Binary PSO (BPSO), a group of birds consists a matrix with binary entries, control the presence ('1‧) or the absence ('0‧) of nano rod in the array.

  7. Nano photonic sensors for microdamage detection : an exploratory simulation.

    SciTech Connect

    El-Kady, Ihab Fathy; Reda Taha, Mahmoud M.

    2005-04-01

    Nano photonic materials are synthetically manufactured crystals at the nano scale with the target of creating a microstructure with a special electro-magnetic periodicity. Such nano photonic materials have the ability to control light propagation and thus are capable of creating photonic bandgaps in the frequency domain. We propose using nano photonic crystals as sensors to detect microdamage in composite materials. We demonstrate using a simulation model that a nano photonic sensor attached to a composite bar experiences a significant change in its bandgap profile when damage is induced in the composite bar. The model predicts the frequency response of the nano photonic sensor using the transfer matrix method. A damage metric to evaluate the change in the frequency response is developed. Successful developments of nano photonic sensors allow damage identification at scales not attainable using current sensing technologies.

  8. Formulation and Drug Loading Features of Nano-Erythrocytes

    NASA Astrophysics Data System (ADS)

    Dong, Xiaoting; Niu, Yawei; Ding, Yi; Wang, Yuemin; Zhao, Jialan; Leng, Wei; Qin, Linghao

    2017-03-01

    Nano erythrocyte ghosts have recently been used as drug carriers of water-soluble APIs due to inherit biological characteristics of good compatibility, low toxicity, and small side-effect. In this study, we developed a novel drug delivery system based on nano erythrocyte ghosts (STS-Nano-RBCs) to transport Sodium Tanshinone IIA sulfonate (STS) for intravenous use in rat. STS-Nano-RBCs were prepared by hypotonic lysis and by extrusion methods, and its biological properties were investigated compared with STS injection. The results revealed that STS-Nano-RBCs have narrow particle size distribution, good drug loading efficiency, and good stability within 21 days. Compared with STS injection, STS-Nano-RBCs extended the drug release time in vitro and in vivo with better repairing effect on oxidative stress-impaired endothelial cells. These results suggest that the nano erythrocyte ghosts system could be used to deliver STS.

  9. Nano-formulations of drugs: Recent developments, impact and challenges.

    PubMed

    Jeevanandam, Jaison; Chan, Yen San; Danquah, Michael K

    2016-01-01

    Nano-formulations of medicinal drugs have attracted the interest of many researchers for drug delivery applications. These nano-formulations enhance the properties of conventional drugs and are specific to the targeted delivery site. Dendrimers, polymeric nanoparticles, liposomes, nano-emulsions and micelles are some of the nano-formulations that are gaining prominence in pharmaceutical industry for enhanced drug formulation. Wide varieties of synthesis methods are available for the preparation of nano-formulations to deliver drugs in biological system. The choice of synthesis methods depend on the size and shape of particulate formulation, biochemical properties of drug, and the targeted site. This article discusses recent developments in nano-formulation and the progressive impact on pharmaceutical research and industries. Additionally, process challenges relating to consistent generation of nano-formulations for drug delivery are discussed.

  10. Nano-Fiber Reinforced Enhancements in Composite Polymer Matrices

    NASA Technical Reports Server (NTRS)

    Chamis, Christos C.

    2009-01-01

    Nano-fibers are used to reinforce polymer matrices to enhance the matrix dependent properties that are subsequently used in conventional structural composites. A quasi isotropic configuration is used in arranging like nano-fibers through the thickness to ascertain equiaxial enhanced matrix behavior. The nano-fiber volume ratios are used to obtain the enhanced matrix strength properties for 0.01,0.03, and 0.05 nano-fiber volume rates. These enhanced nano-fiber matrices are used with conventional fiber volume ratios of 0.3 and 0.5 to obtain the composite properties. Results show that nano-fiber enhanced matrices of higher than 0.3 nano-fiber volume ratio are degrading the composite properties.

  11. Nano-liquid chromatography in pharmaceutical and biomedical research.

    PubMed

    Gama, Mariana Roberto; Collins, Carol H; Bottoli, Carla B G

    2013-08-01

    Miniaturized separation techniques have emerged as environmentally friendly alternatives to available separation methods. Nano-liquid chromatography (nano-LC), microchip devices and nano-capillary electrophoresis are miniaturized methods that minimize reagent consumption and waste generation. Furthermore, the low levels of analytes, especially in biological samples, promote the search for more highly sensitive techniques; coupled to mass spectrometry, nano-LC has great potential to become an indispensable tool for routine analysis of biomolecules. This short review presents the fundamental aspects of nano-LC analytical instrumentation, discussing practical considerations and the primary differences between miniaturized and conventional instrumentation. Some theoretical aspects are discussed to better explain both the potential and the principal limitations of nano-LC. Recent pharmaceutical and biomedical applications of this separation technique are also presented to indicate the satisfactory performance for complex matrices, especially for proteomic analysis, that is obtained with nano-LC.

  12. Shaping functional nano-objects by 3D confined supramolecular assembly.

    PubMed

    Deng, Renhua; Liang, Fuxin; Li, Weikun; Liu, Shanqin; Liang, Ruijing; Cai, Mingle; Yang, Zhenzhong; Zhu, Jintao

    2013-12-20

    Nano-objects are generated through 3D confined supramolecular assembly, followed by a sequential disintegration by rupturing the hydrogen bonding. The shape of the nano-objects is tunable, ranging from nano-disc, nano-cup, to nano-toroid. The nano-objects are pH-responsive. Functional materials for example inorganic or metal nanoparticles are easily complexed onto the external surface, to extend both composition and microstructure of the nano-objects.

  13. A NANO enhancement to Moore's law

    NASA Astrophysics Data System (ADS)

    Wu, Jerry; Shen, Yin-Lin; Reinhardt, Kitt; Szu, Harold

    2012-06-01

    In the past 46 years, Intel Moore observed an exponential doubling in the number of transistors in every 18 months through the size reduction of individual transistor components since 1965. In this paper, we are exploring the nanotechnology impact upon the Law. Since we cannot break down the atomic size barrier, the fact implies a fundamental size limit at the atomic or Nanotechnology scale. This means, no more simple 18 month doubling as in Moore's Law, but other forms of transistor doubling may happen at a different slope in new directions. We are particularly interested in the Nano enhancement area. (i) 3-D: If the progress in shrinking the in-plane dimensions (2D) is to slow down, vertical integration (3D) can help increasing the areal device transistor density and keep us on the modified Moore's Law curve including the 3rd dimension. As the devices continue to shrink further into the 20 to 30 nm range, the consideration of thermal properties and transport in such nanoscale devices becomes increasingly important. (ii) Carbon Computing: Instead of traditional Transistors, the other types of transistors material are rapidly developed in Laboratories Worldwide, e.g. IBM Spintronics bandgap material and Samsung Nano-storage material, HD display Nanotechnology, which are modifying the classical Moore's Law. We shall consider the overall limitation of phonon engineering, fundamental information unit 'Qubyte' in quantum computing, Nano/Micro Electrical Mechanical System (NEMS), Carbon NanoTubes (CNTs), single layer Graphemes, single strip Nano-Ribbons, etc., and their variable degree of fabrication maturities for the computing and information processing applications.

  14. A selective screen reveals discrete functional domains in Drosophila Nanos.

    PubMed Central

    Arrizabalaga, G; Lehmann, R

    1999-01-01

    The Drosophila protein Nanos encodes an evolutionarily conserved protein with two zinc finger motifs. In the embryo, Nanos protein function is required for establishment of the anterior-posterior body pattern and for the migration of primordial germ cells. During oogenesis, Nanos protein is involved in the establishment and maintenance of germ-line stem cells and the differentiation of oocyte precursor cells. To establish proper embryonic patterning, Nanos acts as a translational regulator of hunchback RNA. Nanos' targets for germ cell migration and development are not known. Here, we describe a selective genetic screen aimed at isolating new nanos alleles. The molecular and genetic analysis of 68 new alleles has allowed us to identify amino acids critical for nanos function. This analysis shows that the CCHC motifs, which coordinate two metal ions, are essential for all known functions of Nanos protein. Furthermore, a region C-terminal to the zinc fingers seems to constitute a novel functional domain within the Nanos protein. This "tail region" of Nanos is required for abdomen formation and germ cell migration, but not for oogenesis. PMID:10581288

  15. Effect of nano-SiO II on bismaleimide composite

    NASA Astrophysics Data System (ADS)

    Geng, Dongbing; Zeng, Liming; Li, Yi; Fu, Qiuzhou; Hu, Bing

    2007-07-01

    This paper is concerned with the effect of nano-SiO II particles on the thermal stability and mechanical behavior of composite materials. A nano-composite of three components is prepared by polymerizing nano-SiO II, chopped carbon fiber and bismalemide resin. The investigation's basic approach involves a blend of experimental and analytical studies to determine structure/property relationship. Nano-composite structures are characterized by dynamic mechanical analysis, and contents of nano-SiO II are subsequently correlated with mechanical properties such as tensile and flexural strength also the modulus. The results indicate that the content of nano-SiO II exhibits significant improvement on glass transition temperature (Tg) with Tg elevation by increasing concentration of nano-SiO II. The higher Tg is the result of steric hindrance by nano-SiO II particles in the nano-composite. The mechanical properties of the tensile and flexural strength are raised at first and followed by decreasing as the amount of nano-SiO II particles increased. All the modulus values mimic the tensile and flexural strength.

  16. Advanced nano lithography via soft materials-derived and reversible nano-patterning methodology for molding of infrared nano lenses

    NASA Astrophysics Data System (ADS)

    Park, Jae Hong; Jang, Hyun Ik; Park, Jun Yong; Jeon, Seok Woo; Kim, Woo Choong; Kim, Hee Yeoun; Ahn, Chi Won

    2015-03-01

    The methodology suggested in this research provides the great possibility of creating nanostructures composed of various materials, such as soft polymer, hard polymer, and metal, as well as Si. Such nanostructures are required for a vast range of optical and display devices, photonic components, physical devices, energy devices including electrodes of secondary batteries, fuel cells, solar cells, and energy harvesters, biological devices including biochips, biomimetic or biosimilar structured devices, and mechanical devices including micro- or nano-scale sensors and actuators.

  17. Synthesis of gold nano-wire and nano-dumbbell shaped colloids and AuC60 nano-clusters

    NASA Astrophysics Data System (ADS)

    Landon, Preston B.; Jarvis, Brandon C.; Gilleland, Cody L.; Renfro, Tim; Gutierrez, Jose; Synowczynski, Jennifer; Hirsch, Samuel G.; Glosser, Robert

    2005-08-01

    A technique for the fabrication of colloidal gold nano-wire and nano-dumbbell shaped particles using carbon nanotubes and rod shaped viruses as templates is described. The gold (Au) encapsulation process was accomplished by the precipitation of gold chloride from aqueous solutions. When this process was conducted in the presence of hydroxylated C60, small pieces of phase-separated composites of AuC60 appeared to have formed. These nano-clusters may turn out to be large noble metal analogs of the alkali metal fullerides with the smallest geometrically possible Au aggregate consisting of 55 gold atoms. The existence of noble metal fullerene composites has been previously theorized. The alkali metal fullerides are examples of phase separated solids and have exhibited superconductivity with temperatures as high 33K. The mechanism required for the binding energy between C60 and gold has been observed to exist between C60 and many of the mirror metals (Al, Ag, Au, Cu, Ni). This binding energy is a charge transfer from the metal Fermi level into the C60 LUMO. If this bonding energy, is greater than the metals coagulation energy an Au/C60 size terminated mechanism during the formation of the gold aggregates by the adhesion of C60 to the surface is energetically favorable.

  18. Molecular modeling in structural nano-toxicology: interactions of nano-particles with nano-machinery of cells.

    PubMed

    Yanamala, Naveena; Kagan, Valerian E; Shvedova, Anna A

    2013-12-01

    Over the past two decades, nanotechnology has emerged as a key player in various disciplines of science and technology. Some of the most exciting applications are in the field of biomedicine - for theranostics (for combined diagnostic and therapeutic purposes) as well as for exploration of biological systems. A detailed understanding of the molecular interactions between nanoparticles and biological nano-machinery - macromolecules, membranes, and intracellular organelles - is crucial for obtaining adequate information on mechanisms of action of nanomaterials as well as a perspective on the long term effects of these materials and their possible toxicological outcomes. This review focuses on the use of structure-based computational molecular modeling as a tool to understand and to predict the interactions between nanomaterials and nano-biosystems. We review major approaches and provide examples of computational analysis of the structural principles behind such interactions. A rationale on how nanoparticles of different sizes, shape, structure and chemical properties can affect the organization and functions of nano-machinery of cells is also presented.

  19. Mechanical Properties of Polymer Nano-composites

    NASA Astrophysics Data System (ADS)

    Srivastava, Iti

    Thermoset polymer composites are increasingly important in high-performance engineering industries due to their light-weight and high specific strength, finding cutting-edge applications such as aircraft fuselage material and automobile parts. Epoxy is the most widely employed thermoset polymer, but is brittle due to extensive cross-linking and notch sensitivity, necessitating mechanical property studies especially fracture toughness and fatigue resistance, to ameliorate the low crack resistance. Towards this end, various nano and micro fillers have been used with epoxy to form composite materials. Particularly for nano-fillers, the 1-100 nm scale dimensions lead to fascinating mechanical properties, oftentimes proving superior to the epoxy matrix. The chemical nature, topology, mechanical properties and geometry of the nano-fillers have a profound influence on nano-composite behavior and hence are studied in the context of enhancing properties and understanding reinforcement mechanisms in polymer matrix nano-composites. Using carbon nanotubes (CNTs) as polymer filler, uniquely results in both increased stiffness as well as toughness, leading to extensive research on their applications. Though CNTs-polymer nano-composites offer better mechanical properties, at high stress amplitude their fatigue resistance is lost. In this work covalent functionalization of CNTs has been found to have a profound impact on mechanical properties of the CNT-epoxy nano-composite. Amine treated CNTs were found to give rise to effective fatigue resistance throughout the whole range of stress intensity factor, in addition to significantly enhancing fracture toughness, ductility, Young's modulus and average hardness of the nano-composite by factors of 57%, 60%, 30% and 45% respectively over the matrix as a result of diminished localized cross-linking. Graphene, a one-atom-thick sheet of atoms is a carbon allotrope, which has garnered significant attention of the scientific community and is

  20. Order of magnitude improvement of nano-contact spin torque nano-oscillator performance.

    PubMed

    Banuazizi, Seyed Amir Hossein; Sani, Sohrab R; Eklund, Anders; Naiini, Maziar M; Mohseni, Seyed Majid; Chung, Sunjae; Dürrenfeld, Philipp; Malm, B Gunnar; Åkerman, Johan

    2017-02-02

    Spin torque nano-oscillators (STNO) represent a unique class of nano-scale microwave signal generators and offer a combination of intriguing properties, such as nano sized footprint, ultrafast modulation rates, and highly tunable microwave frequencies from 100 MHz to close to 100 GHz. However, their low output power and relatively high threshold current still limit their applicability and must be improved. In this study, we investigate the influence of the bottom Cu electrode thickness (tCu) in nano-contact STNOs based on Co/Cu/NiFe GMR stacks and with nano-contact diameters ranging from 60 to 500 nm. Increasing tCu from 10 to 70 nm results in a 40% reduction of the threshold current, an order of magnitude higher microwave output power, and close to two orders of magnitude better power conversion efficiency. Numerical simulations of the current distribution suggest that these dramatic improvements originate from a strongly reduced lateral current spread in the magneto-dynamically active region.

  1. Nano-photonics: past and present

    NASA Astrophysics Data System (ADS)

    Szu, Harold

    2010-04-01

    Nanotech is at the scale of 10-9 meters, located at the mesocopic transition phase, which can take both classical mechanics (CM) and quantum mechanics (QM) descriptions bridging ten orders of magnitude phenomena, between the microscopic world of a single atom at 10-10 meters with the macroscopic world at meters. However, QM principles aid the understanding of any unusual property at the nanotech level. The other major difference between nano-photonics and other forms of optics is that the nano-scale is not very 'hands on'. For the most part, we will not be able to see the components with our naked eyes, but will be required to use some nanotech imaging tools, as follows:

  2. Performance Evaluation of Nano-JASMINE

    NASA Astrophysics Data System (ADS)

    Hatsutori, Y.; Kobayashi, Y.; Gouda, N.; Yano, T.; Murooka, J.; Niwa, Y.; Yamada, Y.

    2011-02-01

    We report the results of performance evaluation of the first Japanese astrometry satellite, Nano-JASMINE. It is a very small satellite and weighs only 35 kg. It aims to carry out astrometry measurement of nearby bright stars (z ≤ 7.5 mag) with an accuracy of 3 milli-arcseconds. Nano-JASMINE will be launched by Cyclone-4 rocket in August 2011 from Brazil. The current status is in the process of evaluating the performances. A series of performance tests and numerical analysis were conducted. As a result, the engineering model (EM) of the telescope was measured to be achieving a diffraction-limited performance and confirmed that it has enough performance for scientific astrometry.

  3. Dynamics of magnetic nano-particle assembly

    NASA Astrophysics Data System (ADS)

    Kondratyev, V. N.

    2010-11-01

    Ferromagnetically coupled nano-particle assembly is analyzed accounting for inter- and intra- particle electronic structures within the randomly jumping interacting moments model including quantum fluctuations due to the discrete levels and disorder. At the magnetic jump anomalies caused by quantization the magnetic state equation and phase diagram are found to indicate an existence of spinodal regions and critical points. Arrays of magnetized nano-particles with multiple magnetic response anomalies are predicted to display some specific features. In a case of weak coupling such arrays exhibit the well-separated instability regions surrounding the anomaly positions. With increasing coupling we observe further structure modification, plausibly, of bifurcation type. At strong coupling the dynamical instability region become wide while the stable regime arises as a narrow islands at small disorders. It is shown that exploring correlations of magnetic noise amplitudes represents convenient analytical tool for quantitative definition, description and study of supermagnetism, as well as self-organized criticality.

  4. Nano-plasmonic phenomena in graphene nanoribbons

    NASA Astrophysics Data System (ADS)

    Fei, Zhe; Goldflam, Michael; Wu, Jhih-Sheng; Dai, Siyuan; Wagner, Martin; McLeod, Alex; Liu, Mengkun; Post, Kirk; Zhu, Shou-En; Janssen, Guido; Fogler, Michael; Basov, Dimitri

    We report on infrared nano-imaging studies of confined plasmon modes inside patterned graphene nanoribbons. The confined geometry of these ribbons leads to distinct mode patterns and strong field enhancement, both of which evolve systematically with the ribbon width and excitation laser frequency. In addition, broadband nano-imaging in a wide mid-infrared region allowed us to evaluate in real space the effect of the plasmon-phonon coupling. Our data and modeling show that the plasmon damping rate increases significantly when approaching the substrate phonon. Furthermore, we observed one-dimensional edge plasmons that propagate strictly along the edges of our patterned graphene nanostructures. These edge modes appear to have a relatively shorter wavelength compared to two-dimensional plasmons.

  5. Magnetic resonances in nano-scale metamaterials

    NASA Astrophysics Data System (ADS)

    Hao, Zhao; Liddle, Alex; Martin, Michael

    2006-03-01

    We have designed, fabricated, and optically measured several different kinds of nano-scale metamaterials. We make use e-beam nano-lithography technology at LBNL's Center for X-Ray Optics for fabricating these structures on extremely thin SiN substrates so that they are close to free-standing. Optical properties were measured as a function of incidence angle and polarization. We directly observe a strong magnetic resonance consistent with a negative magnetic permeability in our samples at mid- and near-IR optical frequencies. We will discuss the results in comparison with detailed simulations, and will discuss the electric dipole or quadrupole resonances observed in the samples. Finally, we will report on our progress towards constructing a fully negative index of refraction meta-material.

  6. Highly sensitive immunoassay based on SERS using nano-Au immune probes and a nano-Ag immune substrate.

    PubMed

    Shu, Lei; Zhou, Jun; Yuan, Xiaocong; Petti, Lucia; Chen, Jinping; Jia, Zhenhong; Mormile, Pasquale

    2014-06-01

    A super-high-sensitivity immunoassay based on surface-enhanced Raman scattering (SERS) was implemented using the nano-Au immune probes and nano-Ag immune substrate. Ultraviolet-visible extinction spectra, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images, and SERS spectra were used to characterise the nano-Au immune probes and the nano-Ag immune substrate. The nano-Ag immune substrate was prepared by the in situ growth of Ag nanoparticles and the subsequent linkage of these nanoparticles with anti-apolipoprotein B on a silicon wafer. The nano-Ag immune substrate exhibited strong SERS activity, excellent reproducibility, and high biospecificity. The nano-Au immune probes were prepared by immobilising 4-mercaptobenzoic acid (4MBA) molecules as a Raman reporter and anti-apolipoprotein B onto the surfaces of Au nanoparticles. It was found that 4MBA induced the aggregation of Au nanoparticles, resulting in the generation of vast hot spots. Moreover, the nano-Au immune probes exhibited strong SERS activity and high biospecificity. A sandwich-type immunoassay structure consisting of the nano-Au immune probes and nano-Ag immune substrate was used to detect the concentration of apolipoprotein B, where the detection limit was as low as 2 fg/mL (3.878×10(-18) mol/L). Taken together, the experimental results indicate that the proposed immunoassay protocol has a great potential application in biological sensing and clinical diagnostics.

  7. Ultimate computing. Biomolecular consciousness and nano Technology

    SciTech Connect

    Hameroff, S.R.

    1987-01-01

    The book advances the premise that the cytoskeleton is the cell's nervous system, the biological controller/computer. If indeed cytoskeletal dynamics in the nanoscale (billionth meter, billionth second) are the texture of intracellular information processing, emerging ''NanoTechnologies'' (scanning tunneling microscopy, Feynman machines, von Neumann replicators, etc.) should enable direct monitoring, decoding and interfacing between biological and technological information devices. This in turn could result in important biomedical applications and perhaps a merger of mind and machine: Ultimate Computing.

  8. Rapid Sintering of Nano-Diamond Compacts

    SciTech Connect

    Osipov, A.; Nauyoks, S; Zerda, T; Zaporozhets, O

    2009-01-01

    Diamond compacts were sintered from nano-size diamond crystals at high pressure, 8 GPa, and temperature above 1500 degrees C for very short times ranging from 5 to 11 s. Structure and mechanical properties of the compacts have been characterized. Although we have not completely avoided graphitization of diamonds, the amount of graphite produced was low, less than 2%, and despite relatively high porosity, the compacts were characterized by high hardness, bulk and Young moduli.

  9. Asphaltenes-based polymer nano-composites

    DOEpatents

    Bowen, III, Daniel E

    2013-12-17

    Inventive composite materials are provided. The composite is preferably a nano-composite, and comprises an asphaltene, or a mixture of asphaltenes, blended with a polymer. The polymer can be any polymer in need of altered properties, including those selected from the group consisting of epoxies, acrylics, urethanes, silicones, cyanoacrylates, vulcanized rubber, phenol-formaldehyde, melamine-formaldehyde, urea-formaldehyde, imides, esters, cyanate esters, allyl resins.

  10. Reversible nano-lithography for commercial approaches

    NASA Astrophysics Data System (ADS)

    Park, Jae Hong; Jang, Hyun Ik; Kim, Woo Choong; Yun, Hae S.; Park, Jun Yong; Jeon, Seok Woo; Kim, Hee Yeoun; Ahn, Chi Won

    2016-04-01

    The methodology suggested in this research provides the great possibility of creating nanostructures composed of various materials, such as soft polymer, hard polymer, and metal, as well as Si. Such nanostructures are required for a vast range of optical and display devices, photonic components, physical devices, energy devices including electrodes of secondary batteries, fuel cells, solar cells, and energy harvesters, biological devices including biochips, biomimetic or biosimilar structured devices, and mechanical devices including micro- or nano-scale sensors and actuators.

  11. Antibacterial characteristics of heated scallop-shell nano-particles.

    PubMed

    Watanabe, Takashi; Fujimoto, Riku; Sawai, Jun; Kikuchi, Mikio; Yahata, Shinya; Satoh, Susumu

    2014-01-01

    Heated scallop-shell (HSS) nano-particles, prepared using a wet grinding mill, and microparticles were examined for their antibacterial activity against vegetative bacterial cells and spores. The median diameters of the nano-particles and micro-particles were approximately 20 nm and 30 µm, respectively. The antibacterial activity of HSS against Escherichia coli increased with an increase in concentration, regardless of particle size; however, the antibacterial activity of the nano-particles was much higher than that of micro-particles. The sporicidal activity of the nano-particles was also much higher than that of micro-particles, with HSS nano-particles able to kill Bacillus subtilis spores. A reduction of more than three orders of magnitude for B. subtilis spores was confirmed following a 30 min treatment at 5 mg/ml and 60℃, showing that the combination of HSS nano-particle treatment with mild heating was particularly effective for controlling bacterial spores.

  12. Electrochemical method of producing nano-scaled graphene platelets

    SciTech Connect

    Zhamu, Aruna; Jang, Joan; Jang, Bor Z.

    2013-09-03

    A method of producing nano-scaled graphene platelets with an average thickness smaller than 30 nm from a layered graphite material. The method comprises (a) forming a carboxylic acid-intercalated graphite compound by an electrochemical reaction; (b) exposing the intercalated graphite compound to a thermal shock to produce exfoliated graphite; and (c) subjecting the exfoliated graphite to a mechanical shearing treatment to produce the nano-scaled graphene platelets. Preferred carboxylic acids are formic acid and acetic acid. The exfoliation step in the instant invention does not involve the evolution of undesirable species, such as NO.sub.x and SO.sub.x, which are common by-products of exfoliating conventional sulfuric or nitric acid-intercalated graphite compounds. The nano-scaled platelets are candidate reinforcement fillers for polymer nanocomposites. Nano-scaled graphene platelets are much lower-cost alternatives to carbon nano-tubes or carbon nano-fibers.

  13. Micro/nano-fabrication technologies for cell biology.

    PubMed

    Qian, Tongcheng; Wang, Yingxiao

    2010-10-01

    Micro/nano-fabrication techniques, such as soft lithography and electrospinning, have been well-developed and widely applied in many research fields in the past decade. Due to the low costs and simple procedures, these techniques have become important and popular for biological studies. In this review, we focus on the studies integrating micro/nano-fabrication work to elucidate the molecular mechanism of signaling transduction in cell biology. We first describe different micro/nano-fabrication technologies, including techniques generating three-dimensional scaffolds for tissue engineering. We then introduce the application of these technologies in manipulating the physical or chemical micro/nano-environment to regulate the cellular behavior and response, such as cell life and death, differentiation, proliferation, and cell migration. Recent advancement in integrating the micro/nano-technologies and live cell imaging are also discussed. Finally, potential schemes in cell biology involving micro/nano-fabrication technologies are proposed to provide perspectives on the future research activities.

  14. Scientific goals of Nano-JASMINE

    NASA Astrophysics Data System (ADS)

    Yamada, Yoshiyuki; Fujita, Sho; Gouda, Naoteru; Kobayashi, Yukiyasu; Hara, Takuji; Nishi, Ryoichi; Yoshioka, Satoshi; Hozumi, Shunsuke

    2013-02-01

    Nano-JASMINE is an ultrasmall Japanese satellite (with a weight of 35 kg), designed to carry out an astrometric mission. The target accuracy is 3 milliarcseconds (mas) for stars brighter than magnitude 7.5 at zw-band wavelengths of 0.6-1.0 μm. The observational strategy is the same as that of Gaia and Hipparcos. The time span of 20 years since the Hipparcos mission will enable us to update the proper motion data obtained at that time. With the help of these updated measurements, we expect that some stars will be resolved into multiple stars. In addition, taking advantage of the small primary mirror (with a diameter of 5 cm), we can measure bright stars which cannot be observed with Gaia because of saturation limits. The core data reduction for the Nano-JASMINE mission will use Gaia's Astrometric Global Iterative Solution (agis). A collaboration between the Gaia agis and Nano-JASMINE teams was initiated in 2007.

  15. The Next Technology Revolution - Nano Electronic Technology

    NASA Astrophysics Data System (ADS)

    Turlik, Iwona

    2004-03-01

    Nanotechnology is a revolutionary engine that will engender enormous changes in a vast majority of today's industries and markets, while potentially creating whole new industries. The impact of nanotechnology is particularly significant in the electronics industry, which is constantly driven by the need for higher performance, increased functionality, smaller size and lower cost. Nanotechnology can influence many of the hundreds of components that are typically assembled to manufacture modern electronic devices. Motorola manufactures electronics for a wide range of industries and communication products. In this presentation, the typical components of a cellular phone are outlined and technology requirements for future products, the customer benefits, and the potential impact of nanotechnology on many of the components are discussed. Technology needs include reliable materials supply, processes for high volume production, experimental and simulation tools, etc. For example, even routine procedures such as failure characterization may require the development of new tools for investigating nano-scale phenomena. Business needs include the development of an effective, high volume supply chain for nano-materials and devices, disruptive product platforms, and visible performance impact on the end consumer. An equally significant long-term industry need is the availability of science and engineering graduates with a multidisciplinary focus and a deep understanding of the fundamentals of nano-technology, that can harness the technology to create revolutionary products.

  16. Nano-education from a European perspective

    NASA Astrophysics Data System (ADS)

    Malsch, I.

    2008-03-01

    At a global level, educating the nanotechnology workforce has been discussed since the beginning of the new millennium. Scientists, engineers and technicians should be trained in nanotechnology. Most educators prefer training students first in their own discipline at the Bachelor level (physics, chemistry, biology, etc) followed by specialisation in nanoscience and technology at the Master's level. Some favour a broad interdisciplinary basic training in different nanosciences followed by specialisation in a particular application area. What constitutes a good nanoscience curriculum is also being discussed, as well as the application of e-learning methodologies. The European Union is stimulating the development of nanoscience education in universities. The Erasmus Mundus programme is funding nanoscience and nanotechnology education programmes involving universities in several European countries. The policy debate in Europe is moving towards vocational training in nanotechnology for educating the technicians needed in industry and research. The EU vocational training institute CEDEFOP published a report in 2005 The EU funded European gateway to nanotechnology Nanoforum has stimulated the accessibility of nano-education throughout Europe with reports and online databases of education courses and materials. For university education, they list courses at the Bachelor, Master's, and PhD level as well as short courses. The EU funded EuroIndiaNet project also reviewed Nano-education courses at the Master's level, short courses, e-learning programmes, summerschools and vocational training courses. In this presentation, I review Nanoforum and other publications on nano-education in Europe and highlight current trends and gaps.

  17. Physical properties of carboxymethyl cellulose based nano-biocomposites with Graphene nano-platelets.

    PubMed

    Ebrahimzadeh, Saba; Ghanbarzadeh, Babak; Hamishehkar, Hamed

    2016-03-01

    Carboxymethyl cellulose (CMC) based bio-nanocomposite filled with graphene nano-platelets (GNPs) was prepared using casting technique. The morphology, thermal, light barrier, water vapor permeability (WVP), contact angle, moisture absorption and mechanical properties of the resulted bio-nanocomposites were investigated. The results indicated with addition of 0.5% w/w GNPs to polymer matrix, ultimate tensile strength (UTS) decreased from 7.74 MPa (in the pure film) to 5.69 MPa however, strain to break (SB) increased from 12.49% to 19.87%. The GNPs caused to reducing of light transmission and increasing of the water repelling nature of nano-biocomposites. However, it had not effect on melting point of CMC based nano-biocomposites.

  18. Nano-fabrication with metallic glass-an exotic material for nano-electromechanical systems.

    PubMed

    Sharma, Parmanand; Kaushik, Neelam; Kimura, Hisamichi; Saotome, Yasunori; Inoue, Akihisa

    2007-01-24

    Completely glassy thin films of Zr-Al-Cu-Ni exhibiting a large supercooled liquid region (DeltaT(x) = 95 K), very smooth surface (R(a) = 0.2 nm) and high value of Vickers hardness (H(v) = 940) were deposited by sputtering. The micro/nano-patterning ability of these films is demonstrated by focused ion beam etching (smallest pattern approximately 12 nm), as well as by the imprint lithography technique (smallest feature approximately 34 nm). These glassy films having very good mechanical and chemical properties, combined with superb nano-patterning ability, integrateable with silicon integrated circuit technology, are promising for fabrication of a wide range of two- or three-dimensional components for future nano-electromechanical systems.

  19. Superconducting properties of Nb-Cu nano-composites and nano-alloys

    NASA Astrophysics Data System (ADS)

    Parab, Pradnya; Kumar, Sanjeev; Bhui, Prabhjyot; Bagwe, Vivas; Bose, Sangita

    2016-05-01

    The evolution of the superconducting transition temperature (Tc) in nano-composite and nano-alloys of Nb-Cu, grown by DC magnetron co-sputtering are investigated. Microstructure of these films depends less strongly on the ratio of Nb:Cu but more on the growth temperature. At higher growth temperature, phase separated granular films of Nb and Cu were formed which showed superconducting transition temperatures (Tc) of ~ 7.2±0.5K, irrespective of the composition. Our results show that this is primarily influenced by the microstructure of the films determined during growth which rules out the superconducting proximity effect expected in these systems. At room temperature growth, films with nano-scale alloying were obtained at the optimal compositional range of 45-70 atomic% (At%) of Nb. These were also superconducting with a Tc of 3.2K.

  20. Nano-imaging and nano-spectroscopy of tunable surface phonon polaritons in hexagonal boron nitride

    NASA Astrophysics Data System (ADS)

    Dai, Siyuan; Fei, Zhe; Ma, Qiong; Rodin, Aleksandr; Wagner, Martin; McLeod, Alexander; Liu, Mengkun; Gannett, Will; Regan, William; Thiemens, Mark; Dominguez, Gerardo; Castro Neto, Antonio; Zettl, Alex; Keilmann, Fritz; Jarillo-Herrero, Pablo; Fogler, Michael; Basov, Dimitri

    2014-03-01

    Van der Waals crystals such as graphene, topological insulators, cuprate high-temperature superconductors, and many other layered structures reveal a rich variety of enigmatic electronic, photonic and magnetic properties. We report infrared (IR) nano-imaging of surface phonon polaritons in a prototypical van-der-Waals crystal: hexagonal boron nitride (hBN). In the setting of an antenna-based IR spectroscopic nanoscope, we accomplished launching, detecting, and real space imaging of the polaritonic waves. We were able to alter both the wavelength and the amplitude of such waves by varying the number of crystal layers in our specimens. We demonstrated a new nano-photonics method for mapping the polariton dispersion. The dispersion is shown to be governed by the crystal thickness according to a scaling law that persists down to a few monolayers. Our results point to novel functionalities of van-der-Waals crystals as reconfigurable nano-photonic materials.

  1. Arrays of recycled power TM polarized nano-antennas.

    PubMed

    Hattori, Haroldo T; Li, Ziyuan

    2013-07-15

    In recent years, plasmonic nano-antennas have been used in a wide range of applications in sensing, particle detection, imaging and Surface Enhanced Raman Scattering (SERS) detection. Also, arrays of nano-antennas have been recently developed to produce more directional radiation beams or to operate over a wide range of wavelengths. In this article, it is shown that small arrays of nano-antennas can be created by recycling the power that flows through their antenna gaps.

  2. Developing NanoFoil-Heated Thin-Film Thermal Battery

    DTIC Science & Technology

    2013-09-01

    NanoFoil-Heated Thin- Film Thermal Battery ..........................................6 3. Results and Discussion 8 3.1 Regulation of Skin ...Developing NanoFoil-Heated Thin- Film Thermal Battery by Michael S. Ding, Frank C. Krieger, and Jeffrey A. Swank ARL-TR-6664 September...TR-6664 September 2013 Developing NanoFoil-Heated Thin- Film Thermal Battery Michael S. Ding, Frank C. Krieger, and Jeffrey A. Swank

  3. Micro and Nano-mediated 3D Cardiac Tissue Engineering

    DTIC Science & Technology

    2011-10-01

    AD_________________ Award Number: W81XWH-08-1-0701 TITLE: Micro and Nano -mediated 3D Cardiac...5a. CONTRACT NUMBER Micro and Nano -mediated 3D Cardiac Tissue Engineering 5b. GRANT NUMBER W81XWH-08-1-0701 5c. PROGRAM ELEMENT NUMBER 6...TATRC-funded Micro and Nano -mediated 3D Cardiac Tissue Engineering is a project of the University of Illinois Center for Nanoscale Science and

  4. Wide Bandgap III-Nitride Micro- and Nano-Photonics

    DTIC Science & Technology

    2008-05-05

    AND DATES COVERED Final Report 10/2003 – 10/2007 4. TITLE AND SUBTITLE Wide Bandgap III-Nitride Micro - and Nano -Photonics 5. FUNDING NUMBERS...device issues and to explore potential applications of III-nitrides for UV micro - and nano -photonic devices. The KSU team has achieved 1. n-type...Award No: DAAD19-03-1-0337 Project Title: Wide Bandgap III-Nitride Micro - and Nano -Photonics PI Name: Hongxing Jiang & Jingyu Lin PI Address

  5. Self Assembled, Ultra-Hydrophobic Micro/Nano-Textured Surfaces

    DTIC Science & Technology

    2007-04-01

    Self Assembled, Ultra-Hydrophobic Micro / Nano -Textured Surfaces by Adam M. Rawlett, Joshua A. Orlicki, Nicole Zander, Afia Karikari, and...5069 ARL-TN-275 April 2007 Self Assembled, Ultra-Hydrophobic Micro / Nano -Textured Surfaces Adam M. Rawlett, Joshua A. Orlicki, and...NUMBER 5b. GRANT NUMBER 4. TITL Self A bled, Ultra-Hydrophobic Micro / Nano -Textured Surfaces 5c. PROGRAM ELEMENT NUMBER E ssem AND SUBTITLE 5d

  6. Gluing Bifurcations in Coupled Spin Torque Nano-Oscillators

    DTIC Science & Technology

    2013-01-01

    REPORT Gluing bifurcations in coupled spin torque nano -oscillators 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: Over the past few years it has been...shown, through theory and experiments, that the AC current produced by spin torque nano -oscillators (STNO), coupled in an array, can lead to feedback...Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211 15. SUBJECT TERMS Nano -oscillators, symmetry, bifurcations Katherine

  7. [Biomimetic mineralization of rod-like cellulose nano-whiskers and spectrum analysis].

    PubMed

    Qu, Ping; Wang, Xuan; Cui, Xiao-xia; Zhang, Li-ping

    2012-05-01

    Cellulose nano-whiskers/nano-hydroxyapatite composite was prepared with biomimetic mineralization using rod-like cellulose nano-whiskers as template. The cellulose nano-whiskers and cellulose nano-whiskers/nano-hydroxyapatite composite were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope-energy dispersive analysis of X-rays (SEM-EDXA). Variation and distribution of carbon, oxygen, calcium, and phosphorus in the composites were studied. The morphologies and growth mechanism of nano-hydroxyapatite were analyzed. The results showed that nano-hydroxyapatite was formed on the surface of cellulose nano-whiskers; the carbon-oxygen ratio of cellulose nano-whiskers and cellulose nano-whiskers/nano-hydroxyapatite composite was 1.81 and 1.54, respectively; the calcium-phosphorus ratio of the composite was 1.70. The nucleation of nano-hydroxyapatite was around the hydroxyl groups of cellulose nano-whiskers. It is suggested that there is coordination between the hydroxyl groups of cellulose nano-whiskers and calcium ions of nano-hydroxyapatite. The nano-hydroxyapatite can distribute in the matrix of cellulose nano-whiskers. From the atomic force microscope (AFM) images, we can see that the diameter of the spherical nano-hydroxyapatite particles was about 20 nm.

  8. Nano-cryosurgery: advances and challenges.

    PubMed

    Liu, Jing; Deng, Zhong-Shan

    2009-08-01

    In clinics, the minimally invasive freezing therapy, commonly known as cryosurgery, has been increasingly used for the controlled destruction of tumor tissue. However, there are still many bottlenecks to impede the success of a cryosurgery. One of the most critical factors has been that insufficient or inappropriate freezing will not completely destroy the target tumor tissues, which as a result may lead to tumor regenesis and thus failure of treatment. In addition, the surrounding healthy tissues may suffer from serious freeze injury due to unavoidable release of a large amount of cold from the freezing probe. To resolve these challenges, we recently proposed a new strategy, termed as nano-cryosurgery, to improve freezing efficiency of the conventional cryosurgical procedure. The basic principle of this protocol is to deliver functional suspension of nanoparticles with favorable physical and/or chemical properties into the target tissues, which then serve as adjuvant or drug carrier either to maximize the freezing heat transfer process, regulate freezing scale, modify ice-ball formation orientation or prevent the surrounding healthy tissues from being frozen. In addition, introduction of nanoparticles during cryosurgery could also help better image the edge of a tumor as well as the margin of the iceball. The new therapy raised many critical fundamental as well as practical issues for solving. This review is dedicated to present a comprehensive review on multiscale fundamental phase change heat transfer issues thus involved. Attentions would span from micro-scale heat transfer in cellular scale to tissue level. Some related thermal physical effects of nanoparticles on the freezing process such as ice nucleation enhancement, water transport during freezing of a single cell will be discussed. Cryosurgical thermal management of using nanoparticles to modify thermal properties of the tissue-particle components, regulate the growth orientation and strength of an ice

  9. Gaseous detonation synthesis and characterization of nano-oxide

    NASA Astrophysics Data System (ADS)

    Yan, Honghao; Wu, Linsong; Li, Xiaojie; Wang, Xiaohong

    2015-07-01

    Gaseous detonation is a new method of heating the precursor of nanomaterials into gas, and integrating it with combustible gas as mixture to be detonated for the synthesis of nanomaterials. In this paper, the mixed gas of oxygen and hydrogen is used as the source for detonation, to synthesize nano TiO2, nano SiO2 and nano SnO2 through gaseous detonation method, characterization and analysis of the products, it was found that the products from gaseous detonation method were of high purity, good dispersion, smaller particle size and even distribution. It also shows that for the synthesis of nano-oxides, gaseous detonation is universal.

  10. Recent Development of Nano-Materials Used in DNA Biosensors

    PubMed Central

    Xu, Kai; Huang, Junran; Ye, Zunzhong; Ying, Yibin; Li, Yanbin

    2009-01-01

    As knowledge of the structure and function of nucleic acid molecules has increased, sequence-specific DNA detection has gained increased importance. DNA biosensors based on nucleic acid hybridization have been actively developed because of their specificity, speed, portability, and low cost. Recently, there has been considerable interest in using nano-materials for DNA biosensors. Because of their high surface-to-volume ratios and excellent biological compatibilities, nano-materials could be used to increase the amount of DNA immobilization; moreover, DNA bound to nano-materials can maintain its biological activity. Alternatively, signal amplification by labeling a targeted analyte with nano-materials has also been reported for DNA biosensors in many papers. This review summarizes the applications of various nano-materials for DNA biosensors during past five years. We found that nano-materials of small sizes were advantageous as substrates for DNA attachment or as labels for signal amplification; and use of two or more types of nano-materials in the biosensors could improve their overall quality and to overcome the deficiencies of the individual nano-components. Most current DNA biosensors require the use of polymerase chain reaction (PCR) in their protocols. However, further development of nano-materials with smaller size and/or with improved biological and chemical properties would substantially enhance the accuracy, selectivity and sensitivity of DNA biosensors. Thus, DNA biosensors without PCR amplification may become a reality in the foreseeable future. PMID:22346713

  11. Nano-based PCMs for building energy efficiency

    SciTech Connect

    Biswas, Kaushik

    2016-01-01

    Thermal storage using phase change materials (PCMs) is seen as a viable method for improving the energy efficiency of buildings. PCMs have been used in building applications in various forms PCM slurries in heat exchangers, macro- or microencapsulated PCMs in building envelopes, bulk PCM for modulating photovoltaic temperatures, etc. In the last decade a new class of PCMs, called nano-enhanced PCM (or nanoPCM), has been extensively investigated with the goal of improving the heat transfer and thermal storage properties of PCMs. NanoPCMs can primarily be categorized as nano-encapsulated PCMs and nanoparticle-PCM composites. The former are nano-sized capsules in which the PCM forms the core and is surrounded by a high-conductivity membrane or shell. The latter consist of PCM supported within nanostructures or nanoparticles dispersed in PCMs. This article reviews the current state of nanoPCM synthesis and characterization of their heat transfer and thermal storage properties. Further, a critical review of nanoPCM applications and their potential energy benefits is performed. Nano-enhanced PCMs exhibit higher thermal conductivities than regular PCM. However, whether the higher conductivity is desirable in all applications and if the property enhancements are worth the cost and effort needed to create nanoPCMs are questions that still need to be answered.

  12. Recent development of nano-materials used in DNA biosensors.

    PubMed

    Xu, Kai; Huang, Junran; Ye, Zunzhong; Ying, Yibin; Li, Yanbin

    2009-01-01

    As knowledge of the structure and function of nucleic acid molecules has increased, sequence-specific DNA detection has gained increased importance. DNA biosensors based on nucleic acid hybridization have been actively developed because of their specificity, speed, portability, and low cost. Recently, there has been considerable interest in using nano-materials for DNA biosensors. Because of their high surface-to-volume ratios and excellent biological compatibilities, nano-materials could be used to increase the amount of DNA immobilization; moreover, DNA bound to nano-materials can maintain its biological activity. Alternatively, signal amplification by labeling a targeted analyte with nano-materials has also been reported for DNA biosensors in many papers. This review summarizes the applications of various nano-materials for DNA biosensors during past five years. We found that nano-materials of small sizes were advantageous as substrates for DNA attachment or as labels for signal amplification; and use of two or more types of nano-materials in the biosensors could improve their overall quality and to overcome the deficiencies of the individual nano-components. Most current DNA biosensors require the use of polymerase chain reaction (PCR) in their protocols. However, further development of nano-materials with smaller size and/or with improved biological and chemical properties would substantially enhance the accuracy, selectivity and sensitivity of DNA biosensors. Thus, DNA biosensors without PCR amplification may become a reality in the foreseeable future.

  13. A nano-cheese-cutter to directly measure interfacial adhesion of freestanding nano-fibers

    NASA Astrophysics Data System (ADS)

    Wang, Xin; Najem, Johnny F.; Wong, Shing-Chung; Wan, Kai-tak

    2012-01-01

    A nano-cheese-cutter is fabricated to directly measure the adhesion between two freestanding nano-fibers. A single electrospun fiber is attached to the free end of an atomic force microscope cantilever, while a similar fiber is similarly prepared on a mica substrate in an orthogonal direction. External load is applied to deform the two fibers into complementary V-shapes, and the force measurement allows the elastic modulus to be determined. At a critical tensile load, "pull-off" occurs when the adhering fibers spontaneously detach from each other, yielding the interfacial adhesion energy. Loading-unloading cycles are performed to investigate repeated adhesion-detachment and surface degradation.

  14. Nano/macro porous bioactive glass scaffold

    NASA Astrophysics Data System (ADS)

    Wang, Shaojie

    Bioactive glass (BG) and ceramics have been widely studied and developed as implants to replace hard tissues of the musculo-skeletal system, such as bones and teeth. Recently, instead of using bulk materials, which usually do not degrade rapidly enough and may remain in the human body for a long time, the idea of bioscaffold for tissue regeneration has generated much interest. An ideal bioscaffold is a porous material that would not only provide a three-dimensional structure for the regeneration of natural tissue, but also degrade gradually and, eventually be replaced by the natural tissue completely. Among various material choices the nano-macro dual porous BG appears as the most promising candidate for bioscaffold applications. Here macropores facilitate tissue growth while nanopores control degradation and enhance cell response. The surface area, which controls the degradation of scaffold can also be tuned by changing the nanopore size. However, fabrication of such 3D structure with desirable nano and macro pores has remained challenging. In this dissertation, sol-gel process combined with spinodal decomposition or polymer sponge replication method has been developed to fabricate the nano-macro porous BG scaffolds. Macropores up to 100microm are created by freezing polymer induced spinodal structure through sol-gel transition, while larger macropores (>200um) of predetermined size are obtained by the polymer sponge replication technique. The size of nanopores, which are inherent to the sol-gel method of glass fabrication, has been tailored using several approaches: Before gel point, small nanopores are generated using acid catalyst that leads to weakly-branched polymer-like network. On the other hand, larger nanopores are created with the base-catalyzed gel with highly-branched cluster-like structure. After the gel point, the nanostructure can be further modified by manipulating the sintering temperature and/or the ammonia concentration used in the solvent

  15. Highly sensitive electrochemical impedance spectroscopic detection of DNA hybridization based on Au(nano)-CNT/PAN(nano) films.

    PubMed

    Zhou, Na; Yang, Tao; Jiang, Chen; Du, Meng; Jiao, Kui

    2009-01-15

    A polyaniline nanofibers (PAN(nano))/carbon paste electrode (CPE) was prepared via dopping PAN(nano) in the carbon paste. The nanogold (Au(nano)) and carbon nanotubes (CNT) composite nanoparticles were bound on the surface of the PAN(nano)/CPE. The immobilization and hybridization of the DNA probe on the Au(nano)-CNT/PAN(nano) films were investigated with differential pulse voltammetry (DPV) and cyclic voltammetry (CV) using methylene blue (MB) as indicator, and electrochemical impedance spectroscopy (EIS) using [Fe(CN)(6)](3-/4-) as redox probe. The voltammetric peak currents of MB increased dramatically owing to the immobilization of the probe DNA on the Au(nano)-CNT/PAN(nano) films, and then decreased obviously owing to the hybridization of the DNA probe with the complementary single-stranded DNA (cDNA). The electron transfer resistance (R(et)) of the electrode surface increased after the immobilization of the probe DNA on the Au(nano)-CNT/PAN(nano) films and rose further after the hybridization of the probe DNA. The remarkable difference between the R(et) value at the DNA-immobilized electrode and that at the hybridized electrode could be used for the label-free EIS detection of the target DNA. The loading of the DNA probe on Au(nano)-CNT/PAN(nano) films was greatly enhanced and the sensitivity for the target DNA detection was markedly improved. The sequence-specific DNA of phosphinothricin acetyltransferase (PAT) gene and the polymerase chain reaction (PCR) amplification of nopaline synthase (NOS) gene from transgenically modified beans were determined with this label-free EIS DNA detection method. The dynamic range for detecting the PAT gene sequence was from 1.0 x 10(-12)mol/L to 1.0 x 10(-6)mol/L with a detection limit of 5.6 x 10(-13)mol/L.

  16. Ultrafast Nonlinear Plasmonics of Single Nano-Objects

    NASA Astrophysics Data System (ADS)

    Del Fatti, Natalia

    Investigating, understanding and modeling the physical properties of nano-objects are intense fields of research. Of particular interest are metal-based nano-objects, where their morphology and environment dependent surface plasmon resonances (SPR) have been extensively exploited to design new optical systems. As a SPR is associated to electromagnetic local field enhancement in the nano-object, it also leads to enhancement of its optical nonlinearity, opening many possibilities for investigating fundamental processes at nanoscale. Most of these studies were performed on large ensembles of nano-objects, providing mean information which impedes detailed comparison between experimental data and theoretical models. With the advance of single nanoparticle spectroscopy methods, the linear and nonlinear responses of a single nano-object can now be addressed, which, associated to determination of its morphology by electron microscopy, opens the way to their quantitative modeling. In this context we discuss experimental and theoretical investigations of the ultrafast response of individual model nano-objects, either formed by a single particle (gold nanorod) or by two particles at a nanometric distance (gold-silver nano-dimer). Results obtained in gold nanorods are in excellent quantitative agreement with a model computing the change of the metal dielectric function due to ultrafast electron heating and relaxation. This shows that the nonlinear response of a metal nano-object can be fully described as that of the bulk metal enhanced by plasmonic effects. Extension of these studies to more complex nano-objects, as nano-dimers formed by two different materials, permits analysis of the impact of their interaction. We demonstrate here the existence of Fano effect in the absorption of a single Ag-Au dimer, experimentally proving previous theoretical predictions. Furthermore, we show that ultrafast pump-probe nonlinear spectroscopy permits to selectively address at nanoscale only

  17. Antibacterial performance of nano polypropylene filter media containing nano-TiO2 and clay particles

    NASA Astrophysics Data System (ADS)

    Shafiee, Sara; Zarrebini, Mohammad; Naghashzargar, Elham; Semnani, Dariush

    2015-10-01

    Disinfection and elimination of pathogenic microorganisms from liquid can be achieved by filtration process using antibacterial filter media. The advent of nanotechnology has facilitated the introduction of membranes consisting of nano-fiber in filtration operations. The melt electro-spun fibers due to their extremely small diameters are used in the production of this particular filtration medium. In this work, antibacterial polypropylene filter medium containing clay particles and nano-TiO2 were made using melt electro-spun technology. Antibacterial performance of polypropylene nano-filters was evaluated using E. coli bacteria. Additionally, filtration efficiency of the samples in terms fiber diameter, filter porosity, and fiber distribution using image processing technique was determined. Air permeability and dust aerosol tests were conducted to establish the suitability of the samples as a filter medium. It was concluded that as far as antibacterial property is concerned, nano-fibers filter media containing clay particles are preferential to similar media containing TiO2 nanoparticles.

  18. Bio-inspired nano tools for neuroscience.

    PubMed

    Das, Suradip; Carnicer-Lombarte, Alejandro; Fawcett, James W; Bora, Utpal

    2016-07-01

    Research and treatment in the nervous system is challenged by many physiological barriers posing a major hurdle for neurologists. The CNS is protected by a formidable blood brain barrier (BBB) which limits surgical, therapeutic and diagnostic interventions. The hostile environment created by reactive astrocytes in the CNS along with the limited regeneration capacity of the PNS makes functional recovery after tissue damage difficult and inefficient. Nanomaterials have the unique ability to interface with neural tissue in the nano-scale and are capable of influencing the function of a single neuron. The ability of nanoparticles to transcend the BBB through surface modifications has been exploited in various neuro-imaging techniques and for targeted drug delivery. The tunable topography of nanofibers provides accurate spatio-temporal guidance to regenerating axons. This review is an attempt to comprehend the progress in understanding the obstacles posed by the complex physiology of the nervous system and the innovations in design and fabrication of advanced nanomaterials drawing inspiration from natural phenomenon. We also discuss the development of nanomaterials for use in Neuro-diagnostics, Neuro-therapy and the fabrication of advanced nano-devices for use in opto-electronic and ultrasensitive electrophysiological applications. The energy efficient and parallel computing ability of the human brain has inspired the design of advanced nanotechnology based computational systems. However, extensive use of nanomaterials in neuroscience also raises serious toxicity issues as well as ethical concerns regarding nano implants in the brain. In conclusion we summarize these challenges and provide an insight into the huge potential of nanotechnology platforms in neuroscience.

  19. Combined Toxicity of Nano-ZnO and Nano-TiO2: From Single- to Multinanomaterial Systems.

    PubMed

    Tong, Tiezheng; Wilke, Carolyn M; Wu, Jinsong; Binh, Chu Thi Thanh; Kelly, John J; Gaillard, Jean-François; Gray, Kimberly A

    2015-07-07

    Previous studies on the toxicity of engineered nanomaterials (ENMs) have been primarily based on testing individual ENMs, so little is known about the interactions and combined toxicity of multiple ENMs. In this study the toxicity of chemically stable nano-TiO2 and soluble nano-ZnO was investigated individually and in combination, by monitoring bacterial cell membrane integrity and ATP levels in a natural aqueous medium (Lake Michigan water). Both nano-TiO2 and nano-ZnO damage bacterial cell membranes under simulated solar irradiation (SSI), but their phototoxicity is not additive. Nano-ZnO at 1 mg/L, for example, surprisingly eliminates the damaging effect of nano-TiO2 at 10 mg/L. This phenomenon does not correlate with reactive oxygen species production, but is explained by a reduced extent of bacteria/nano-TiO2 contact in the presence of both nano-ZnO and dissolved zinc. The presence of nano-ZnO also exerts a significant decrease in bacterial ATP levels both under SSI and in the dark, a stress effect not captured by measuring bacterial cell membrane integrity. This inhibitory effect of nano-ZnO, however, is reduced somewhat by nano-TiO2 due to the adsorption of Zn(2+). Therefore, our results reveal that nanoparticle interactions and surface complexation reactions alter the original toxicity of individual nanoparticles and that comprehensive assessments of potential ENM toxicity in the environment require careful integration of complex physicochemical interactions between ENMs and various biological responses.

  20. Biological effects of a nano red elemental selenium.

    PubMed

    Zhang, J S; Gao, X Y; Zhang, L D; Bao, Y P

    2001-01-01

    A novel selenium form, nano red elemental selenium (Nano-Se) was prepared by adding bovine serum albumin to the redox system of selenite and glutathione. Nano-Se has a 7-fold lower acute toxicity than sodium selenite in mice (LD(50) 113 and 15 mg Se/kg body weight respectively). In Se-deficient rat, both Nano-Se and selenite can increase tissue selenium and GPx activity. The biological activities of Nano-Se and selenite were compared in terms of cell proliferation, enzyme induction and protection against free racial-mediated damage in human hepatoma HepG2 cells. Nano-Se and selenite are similarly cell growth inhibited and stimulated synthesis of glutathione peroxidase (GPx), phospholipid hydroperoxide glutathione peroxidase (PHGPx) and thioredoxin reductase (TR). When HepG2 cells were co-treated with selenium and glutathione, Nano-Se showed less pro-oxidative effects than selenite, as measured by cell growth. These results demonstrate that Nano-Se has a similar bioavailability in the rat and antioxidant effects on cells.

  1. Nano Traditional Chinese Medicine: Current Progresses and Future Challenges.

    PubMed

    Huang, Yi; Zhao, Yinglan; Liu, Fang; Liu, Songqing

    2015-01-01

    Nano traditional Chinese medicine (nano TCM) refers to bioactive ingredients, bioactive parts, medicinal materials or complex prescription, being approximately 100 nm in size, which are processed by nanotechnology. Nano TCM is a product of the TCM modernization, and is an application of nanotechnology in the field of TCM. This article reviews literatures on researches of nano TCM, which were published in the past 15 years. Different nanotechnologies have been used in preparation of Nano TCM in view of the varying aims of the study. The mechanical crushing technology is the main approach for nanolization of TCM material and complex prescription, and nanoparticulate drug delivery systems is the main approach for nanolization of bioactive ingredients or bioactive parts in TCM. Nano TCM has a number of advantages, for example, enhancing the bioavailability of TCM, reducing the adverse effects of TCM, achieving sustained release, attaining targeted delivery, enhancing pharmacological effects and improving the administration route of TCM. However, there are still many problems that must be resolved in nano TCM research. The main challenges to nano TCM include the theory system of TCM modernization, preparation technology, safety and stability, etc.

  2. Nano-Bio Quantum Technology for Device-Specific Materials

    NASA Technical Reports Server (NTRS)

    Choi, Sang H.

    2009-01-01

    The areas discussed are still under development: I. Nano structured materials for TE applications a) SiGe and Be.Te; b) Nano particles and nanoshells. II. Quantum technology for optical devices: a) Quantum apertures; b) Smart optical materials; c) Micro spectrometer. III. Bio-template oriented materials: a) Bionanobattery; b) Bio-fuel cells; c) Energetic materials.

  3. Development of Nano Processing Technology for Shape Memory Alloy Fibers

    DTIC Science & Technology

    2011-01-30

    Final Report AOARD-09-4037 (FA2386-09-1-4037) Title: Development of nano processing technology for shape memory alloy fibers PI: Hiroyuki...4. TITLE AND SUBTITLE Development of nano processing technology for shape memory alloy fibers 5a. CONTRACT NUMBER FA23860914037 5b. GRANT NUMBER

  4. Tensile/Shear Behaviour of Multi-stitched/Nano Composites

    NASA Astrophysics Data System (ADS)

    Bilisik, Kadir; Kaya, Gaye

    2017-02-01

    This study aims to investigate tensile/shear behavior of multi-stitched/nano composites. For this purpose, non-stitched, non-stitched/nano, multi-stitched and multi-stitched/nano composites were made. It was shown that the warp/filling tensile strength and modulus of composites were slightly reduced in both multi-stitched and multi-stitched/nano composites due to fiber breakage that resulted from the multi-stitching process. In addition, there were not significant differences between non-stitched and multi-stitched structures. The non-stitched/nano composite showed slightly higher in-plane shear strength compared with the non-stitched composite. The in-plane shear strength of the non-stitched composite, on the other hand, increased steadily compared to the multi-stitched composite because of the stitching process and the interface between the stitching yarn and polymer matrix. Stitching significantly improved the delamination resistance in the multi-stitched and multi-stitched/nano composites experienced a small amount of damaged areas. The incorporation of nano silica improved the damage resistance of multi-stitched composites. Therefore, the damaged tolerance composite was developed with stitching and the addition of the nano silica for various industrial applications, such as electronic boards.

  5. Synthesis, Characterization and Application of Functional Carbon Nano Materials

    DTIC Science & Technology

    2014-05-05

    NO. 0704-0188 3. DATES COVERED (From - To) - UU UU UU UU 22-07-2014 Approved for public release; distribution is unlimited. SYNTHESIS ...CHARACTERIZATION AND APPLICATION OFFUNCTIONAL CARBON NANO MATERIALS The synthesis , characterizations and applications of carbon nanomaterials, including carbon...PR 00931 -1790 ABSTRACT SYNTHESIS , CHARACTERIZATION AND APPLICATION OFFUNCTIONAL CARBON NANO MATERIALS Report Title The synthesis , characterizations

  6. Towards sustainability: new approaches to nano-drug preparation.

    PubMed

    Cheow, Wean Sin; Xu, Rong; Hadinoto, Kunn

    2013-01-01

    The conversion of drugs into drug nanoparticles (nano-drugs) represents a feasible method to enhance bioavailability of otherwise sparingly soluble-drugs. Nano-drugs enhance bioavailability through the improvement of dissolution rate and saturation solubility of drugs, by virtue of their small sizes. Nano-drugs available in the market are usually produced by top-down methods, such as wet milling and high pressure homogenization. These conventional top-down methods, however, suffer from high energy and time requirement, as well as wide and inconsistent nano-drug size distribution. Furthermore, commercially available nano-drugs are predominantly crystalline while amorphous nano-drugs are largely neglected despite their propensity to generate high saturation solubility. In this review, nonconventional methods to prepare crystalline and amorphous nano-drugs are discussed, with the bioavailability enhancing characteristics highlighted. Both top-down and bottom-up methods are covered, finally, a sustainability-based perspective comparing amorphous and crystalline nano-drugs is presented.

  7. Nano-Engineered Drug Combinations for Breast Cancer Treatment

    DTIC Science & Technology

    2012-06-01

    Breast Cancer Treatment PRINCIPAL INVESTIGATOR: Joerg Lahann, Ph.D. CONTRACTING...CONTRACT NUMBER Nano-Engineered Drug Combinations for Breast Cancer Treatment 5b. GRANT NUMBER W81XWH-11-1-0111 5c. PROGRAM ELEMENT NUMBER 6...10 19b. TELEPHONE NUMBER (include area code) 2 Nano-engineered Drug Combinations for Breast Cancer Treatment Progress Report

  8. The reactivity of nano silica with calcium hydroxide.

    PubMed

    Lin, Qing; Xu, Zhongzi; Lan, Xianghui; Ni, Yaru; Lu, Chunhua

    2011-11-01

    The reactivity of nano silica (SiO₂) with calcium hydroxide (Ca(OH)₂) was evaluated and characterized in this study. Ca(OH)₂ activated nano SiO₂ takes place through an exothermic process, which is mainly attributed to the breakdown of Si-O-Si bonds. Ca(2+) offsets the charge imbalance and bonds to Si-OH and Si-O(-) giving rise to calcium silicate hydrate (CSH) gel. Care has to be taken that the reactivity of nano SiO₂ with Ca(OH) ₂significantly depends on the Q³ percentage in nano SiO ₂. Q³ percentages significantly influence the reaction kinetic of nano SiO₂ . The higher Q³ percentage results in a higher reaction degree of nano SiO₂ with Ca(OH)₂ and shorter setting times of the pastes. The higher Q³ percentage results in a lower total reaction heat of nano SiO₂ with Ca(OH)₂. It is suggested that the Q³ percentages of nano SiO₂ should be in excess of 30% to keep the satisfactory setting properties of the pastes for the application requirements of bone cement.

  9. Current safety practices in nano-research laboratories in China.

    PubMed

    Zhang, Can; Zhang, Jing; Wang, Guoyu

    2014-06-01

    China has become a key player in the global nanotechnology field, however, no surveys have specifically examined safety practices in the Chinese nano-laboratories in depth. This study reports results of a survey of 300 professionals who work in research laboratories that handle nanomaterials in China. We recruited participants at three major nano-research laboratories (which carry out research in diverse fields such as chemistry, material science, and biology) and the nano-chemistry session of the national meeting of the Chinese Chemical Society. Results show that almost all nano-research laboratories surveyed had general safety regulations, whereas less than one third of respondents reported having nanospecific safety rules. General safety measures were in place in most surveyed nano-research laboratories, while nanospecific protective measures existed or were implemented less frequently. Several factors reported from the scientific literature including nanotoxicology knowledge gaps, technical limitations on estimating nano-exposure, and the lack of nano-occupational safety legislation may contribute to the current state of affairs. With these factors in mind and embracing the precautionary principle, we suggest strengthening or providing nanosafety training (including raising risk awareness) and establishing nanosafety guidelines in China, to better protect personnel in the nano-workplace.

  10. Nano-JASMINE: Simulation of Data Outputs

    NASA Astrophysics Data System (ADS)

    Kobayashi, Y.; Yano, T.; Hatsutori, Y.; Gouda, N.; Murooka, J.; Niwa, Y.; Yamada, Y.

    2011-02-01

    We simulated the data outputs of the first Japanese astrometry satellite Nano-JASMINE, which is scheduled to be launched by the Cyclone-4 rocket in August 2011. The simulations were carried out using existing stellar catalogues such as the Hipparcos catalogue, the Tycho catalogue, and the Guide Star catalogue version 2.3. Several statics are shown such as the number of stars those will be measured distances using annual aberration observations. The method for determining the initial direction of the satellite's spin axis has also been discussed. In this case, the frequency of bright stars observed by the satellite is an important factor.

  11. PLA micro- and nano-particles.

    PubMed

    Lee, Byung Kook; Yun, Yeonhee; Park, Kinam

    2016-12-15

    Poly(d,l-lactic acid) (PLA) has been widely used for various biomedical applications for its biodegradable, biocompatible, and nontoxic properties. Various methods, such as emulsion, salting out, and precipitation, have been used to make better PLA micro- and nano-particle formulations. They are widely used as controlled drug delivery systems of therapeutic molecules, including proteins, genes, vaccines, and anticancer drugs. Even though PLA-based particles have challenges to overcome, such as low drug loading capacity, low encapsulation efficiency, and terminal sterilization, continuous innovations in particulate formulations will lead to development of clinically useful formulations.

  12. Towards future systems with nano-optics contributions

    NASA Astrophysics Data System (ADS)

    Kaminska, Bozena; Najiminaini, Mohamadreza; Chuo, Yindar; Landrock, Clint; Omrane, Badr; Carson, Jeffrey J. L.

    2013-03-01

    The long anticipated deployment of nano-optics that can enable next generation computing has encountered several practical impediments that have delayed widespread adoption in commercial processes. However, the global market in nano-enabled products is expected to grow to over $80B USD within the next 3 years. In response, the research community is creating solutions to overcome challenging issues such as reliability and cost-effective fabrication. New approaches in sensing, continuous uptime powering, and post silicon manufacturing will maximize overall performance and allow unprecedented commercial applications. This paper reviews present limitations of nano-optics and then considers the new generation of devices and their manufacturing that may turn promises into reality. We highlight several recent innovations: high sensitivity/selectivity nano-optical sensing devices; sustainable power from polymer energy harvesting and storage; optical variable devices for visual authentication of secure documents; and nano-template masters for high-volume manufacturing.

  13. Photo-nano immunotherapy for metastatic cancers (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Zhou, Feifan

    2016-03-01

    We constructed a multifunction nano system SWNT-GC and investigated the synergize photothermal and immunological effects. Here, we improve the SWNT-GC nano system and design a new synergistic nano-particle, both have the photothermal effects and immunological effects. We investigate the therapeutic effects and detect the immune response with metastatic mouse tumor models. We also study the therapeutic mechanism after treatment in vitro and in vivo. With the enhancement of nano-materials on photothermal effects, laser treatment could destroy primary tumor and protect normal tissue with low dose laser irradiation. With the immunological effects of nano-materials, the treatment could trigger specific antitumor immune response, to eliminate the metastasis tumor. It is providing a promising treatment modality for the metastatic cancers.

  14. Nano-superconducting quantum interference devices with suspended junctions

    SciTech Connect

    Hazra, D.; Hasselbach, K.; Kirtley, J. R.

    2014-04-14

    Nano-Superconducting Quantum Interference Devices (nano-SQUIDs) are usually fabricated from a single layer of either Nb or Al. We describe here a simple method for fabricating suspended nano-bridges in Nb/Al thin-film bilayers. We use these suspended bridges, which act as Josephson weak links, to fabricate nano-SQUIDs which show critical current oscillations at temperatures up to 1.5 K and magnetic flux densities up to over 20 mT. These nano-SQUIDs exhibit flux modulation depths intermediate between all-Al and all-Nb devices, with some of the desirable characteristics of both. The suspended geometry is attractive for magnetic single nanoparticle measurements.

  15. Magnetic switching probability of perpendicularly magnetized nano-dot

    NASA Astrophysics Data System (ADS)

    Wibowo, N. A.; Trihandaru, S.

    2016-11-01

    Understanding of magnetization reversal mode plays an important role in spintronic devices performance. Especially in Heat Assisted Magnetic Recording, the contribution of thermal field in the magnetization dynamics becomes a crucial aspect which should be further explored. In this paper, Landau Lifshift-Gilbert equation was employed to investigate the magnetic switching dynamics for nano-dots with different magnetic anisotropies. This micromagnetic study shows that these nano-dots exhibit the different mode of switching. Multi-domain configuration dictates the switching process for nano-dot with strong magnetic anisotropy before magnetized in the driven magnetic field direction. Meanwhile, multi-domain configuration, domain-wall nucleation, and propagation take place in the process to achieve magnetized single-domain for the nano-dot with the lower level of magnetic anisotropy. Furthermore, in the absence of the external magnetic field, magnetic moments of this low magnetic anisotropies nano-dot is more probably to reverse.

  16. Nano-liquid chromatography applied to enantiomers separation.

    PubMed

    Fanali, Salvatore

    2017-02-24

    This paper presents the state of the art concerning the separation of chiral compounds by means of nano-liquid chromatography (nano-LC). The enantiomers' separation and determination are a subject of fundamental importance in various application fields such as pharmaceutical industry, biomedicine, food, agrochemical etc. Nano-LC is a miniaturized chromatographic technique offering some advantages over conventional ones such as low consumption of mobile phase, sample volume and amount of chiral stationary phase, reduced costs etc. This is reported in the first part of the paper illustrating the features of the nano-LC. In addition, chiral resolution methods are briefly illustrated. Some chiral selectors, used in high-performance liquid chromatography have also been applied in nano-LC including cyclodextrins, glycopeptide antibiotics, modified polysaccharides etc. This is discussed in the second part of the review. Finally some examples of the applications available in literature are reported.

  17. [The genetic toxicity and toxicology mechanism of metal nano materials].

    PubMed

    Shen, Liping; Wang, Zhidong; Zhou, Pingkun

    2015-09-01

    Although metal nano materials have been widely used in various fields, the potential risks of it still could not be neglected. In this paper, the effects and mechanisms of genotoxicity caused by different nano materials were discussed. Human body can be exposed to metal nano materials through multiple pathways, metals nano follow the blood stream in circulatory system and distribute to organs. Metal nano particles are mainly uptaken into cells by endocytosis, and direct or indirect damages to genes can be induced by these particles after metabolism in cells. These damages would affect the course of cell cycle and the stability of the genome, resulting in gene mutation or chromosome aberration, and even leading to the death or malignant transformation of cells.

  18. Measuring Understanding of Nanoscience and Nanotechnology: Development and Validation of the Nano-Knowledge Instrument (NanoKI)

    ERIC Educational Resources Information Center

    Schönborn, K. J.; Höst, G. E.; Lundin Palmerius, K. E.

    2015-01-01

    As the application of nanotechnology in everyday life impacts society, it becomes critical for citizens to have a scientific basis upon which to judge their perceived hopes and fears of 'nano'. Although multiple instruments have been designed for assessing attitudinal and affective aspects of nano, surprisingly little work has focused on…

  19. Biomineralization regulation by nano-sized features in silk fibroin proteins: synthesis of water-dispersible nano-hydroxyapatite.

    PubMed

    Huang, Xiaowei; Liu, Xi; Liu, Shanshan; Zhang, Aili; Lu, Qiang; Kaplan, David L; Zhu, Hesun

    2014-11-01

    In the present study, silk fibroin (SF) was used as a template to prepare nano-hydroxyapatite (nano-HA) via a biomineralization process. We observed that the content of SF affected both the morphology and water dispersibility of nano-HA particles. Scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), zetasizer, and Fourier transform infrared spectroscopy (FTIR) were used to examine nano-HA particle features including the surface morphology, aggregation performance, and crystallization. Rod-like nano-HA particles with desired water dispersibility were achieved when the ratio of SF/HA (calculated) was above 7:3. SEM, TEM, and zeta potential results revealed that nano-HA particles were enclosed by the SF which formed a negative charge layer preventing the aggregation of HA nanoparticles in aqueous solution. Moreover, the nano-HA particles were able to re-disperse in water without precipitation for two weeks at room temperature, 60°C, and 90°C. Our work suggested a facile and effective approach of designing water-dispersible nano-HA particles which may have wide potential application in tissue engineering especially bone regeneration.

  20. Minimum ignition energy of nano and micro Ti powder in the presence of inert nano TiO₂ powder.

    PubMed

    Chunmiao, Yuan; Amyotte, Paul R; Hossain, Md Nur; Li, Chang

    2014-06-15

    The inerting effect of nano-sized TiO2 powder on ignition sensitivity of nano and micro Ti powders was investigated with a Mike 3 apparatus. "A little is not good enough" is also suitable for micro Ti powders mixed with nano-sized solid inertants. MIE of the mixtures did not significantly increase until the TiO2 percentage exceeded 50%. Nano-sized TiO2 powders were ineffective as an inertant when mixed with nano Ti powders, especially at higher dust loadings. Even with 90% nano TiO2 powder, mixtures still showed high ignition sensitivity because the statistic energy was as low as 2.1 mJ. Layer fires induced by ignited but unburned metal particles may occur for micro Ti powders mixed with nano TiO2 powders following a low level dust explosion. Such layer fires could lead to a violent dust explosion after a second dispersion. Thus, additional attention is needed to prevent metallic layer fires even where electric spark potential is low. In the case of nano Ti powder, no layer fires were observed because of less flammable material involved in the mixtures investigated, and faster flame propagation in nanoparticle clouds.

  1. Nano silver and nano zinc-oxide in surface waters - exposure estimation for Europe at high spatial and temporal resolution.

    PubMed

    Dumont, Egon; Johnson, Andrew C; Keller, Virginie D J; Williams, Richard J

    2015-01-01

    Nano silver and nano zinc-oxide monthly concentrations in surface waters across Europe were modeled at ~6 x 9 km spatial resolution. Nano-particle loadings from households to rivers were simulated considering household connectivity to sewerage, sewage treatment efficiency, the spatial distribution of sewage treatment plants, and their associated populations. These loadings were used to model temporally varying nano-particle concentrations in rivers, lakes and wetlands by considering dilution, downstream transport, water evaporation, water abstraction, and nano-particle sedimentation. Temporal variability in concentrations caused by weather variation was simulated using monthly weather data for a representative 31-year period. Modeled concentrations represent current levels of nano-particle production.Two scenarios were modeled. In the most likely scenario, half the river stretches had long-term average concentrations exceeding 0.002 ng L(-1) nano silver and 1.5 ng L(-1) nano zinc oxide. In 10% of the river stretches, these concentrations exceeded 0.18 ng L(-1) and 150 ng L(-1), respectively. Predicted concentrations were usually highest in July.

  2. Nano-volcanic Eruption of Silver

    NASA Astrophysics Data System (ADS)

    Lin, Shih-Kang; Nagao, Shijo; Yokoi, Emi; Oh, Chulmin; Zhang, Hao; Liu, Yu-Chen; Lin, Shih-Guei; Suganuma, Katsuaki

    2016-10-01

    Silver (Ag) is one of the seven metals of antiquity and an important engineering material in the electronic, medical, and chemical industries because of its unique noble and catalytic properties. Ag thin films are extensively used in modern electronics primarily because of their oxidation-resistance. Here we report a novel phenomenon of Ag nano-volcanic eruption that is caused by interactions between Ag and oxygen (O). It involves grain boundary liquation, the ejection of transient Ag-O fluids through grain boundaries, and the decomposition of Ag-O fluids into O2 gas and suspended Ag and Ag2O clusters. Subsequent coating with re-deposited Ag-O and the de-alloying of O yield a conformal amorphous Ag coating. Patterned Ag hillock arrays and direct Ag-to-Ag bonding can be formed by the homogenous crystallization of amorphous coatings. The Ag “nano-volcanic eruption” mechanism is elaborated, shedding light on a new mechanism of hillock formation and new applications of amorphous Ag coatings.

  3. Low Energy Dissipation Nano Device Research

    NASA Astrophysics Data System (ADS)

    Yu, Jenny

    2015-03-01

    The development of research on energy dissipation has been rapid in energy efficient area. Nano-material power FET is operated as an RF power amplifier, the transport is ballistic, noise is limited and power dissipation is minimized. The goal is Green-save energy by developing the Graphene and carbon nantube microwave and high performance devices. Higher performing RF amplifiers can have multiple impacts on broadly field, for example communication equipment, (such as mobile phone and RADAR); higher power density and lower power dissipation will improve spectral efficiency which translates into higher system level bandwidth and capacity for communications equipment. Thus, fundamental studies of power handling capabilities of new RF (nano)technologies can have broad, sweeping impact. Because it is critical to maximizing the power handling ability of grephene and carbon nanotube FET, the initial task focuses on measuring and understanding the mechanism of electrical breakdown. We aim specifically to determine how the breakdown voltage in graphene and nanotubes is related to the source-drain spacing, electrode material and thickness, and substrate, and thus develop reliable statistics on the breakdown mechanism and probability.

  4. Gold nano-particles fixed on glass

    NASA Astrophysics Data System (ADS)

    Worsch, Christian; Wisniewski, Wolfgang; Kracker, Michael; Rüssel, Christian

    2012-09-01

    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 SiO2 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.

  5. Spiders spinning electrically charged nano-fibres.

    PubMed

    Kronenberger, Katrin; Vollrath, Fritz

    2015-01-01

    Most spider threads are on the micrometre and sub-micrometre scale. Yet, there are some spiders that spin true nano-scale fibres such as the cribellate orb spider, Uloborus plumipes. Here, we analyse the highly specialized capture silk-spinning system of this spider and compare it with the silk extrusion systems of the more standard spider dragline threads. The cribellar silk extrusion system consists of tiny, morphologically basic glands each terminating through exceptionally long and narrow ducts in uniquely shaped silk outlets. Depending on spider size, hundreds to thousands of these outlet spigots cover the cribellum, a phylogenetically ancient spinning plate. We present details on the unique functional design of the cribellate gland-duct-spigot system and discuss design requirements for its specialist fibrils. The spinning of fibres on the nano-scale seems to have been facilitated by the evolution of a highly specialist way of direct spinning, which differs from the aqua-melt silk extrusion set-up more typical for other spiders.

  6. Nano-volcanic Eruption of Silver

    PubMed Central

    Lin, Shih-kang; Nagao, Shijo; Yokoi, Emi; Oh, Chulmin; Zhang, Hao; Liu, Yu-chen; Lin, Shih-guei; Suganuma, Katsuaki

    2016-01-01

    Silver (Ag) is one of the seven metals of antiquity and an important engineering material in the electronic, medical, and chemical industries because of its unique noble and catalytic properties. Ag thin films are extensively used in modern electronics primarily because of their oxidation-resistance. Here we report a novel phenomenon of Ag nano-volcanic eruption that is caused by interactions between Ag and oxygen (O). It involves grain boundary liquation, the ejection of transient Ag-O fluids through grain boundaries, and the decomposition of Ag-O fluids into O2 gas and suspended Ag and Ag2O clusters. Subsequent coating with re-deposited Ag-O and the de-alloying of O yield a conformal amorphous Ag coating. Patterned Ag hillock arrays and direct Ag-to-Ag bonding can be formed by the homogenous crystallization of amorphous coatings. The Ag “nano-volcanic eruption” mechanism is elaborated, shedding light on a new mechanism of hillock formation and new applications of amorphous Ag coatings. PMID:27703220

  7. Wetting of topological nano-patterned surfaces

    NASA Astrophysics Data System (ADS)

    Gang, O.; Alvine, K.; Black, C. T.

    2005-03-01

    We have investigated the evolution of simple hydrocarbon and fluorocarbon liquid films on nano-patterned surfaces of near-hexagonally packed 20 nm wide nano-cavities [1]. Our x-ray measurements show that the behavior of wetting films on patterned surfaces differs from the expected δμ-1/3 dependence found for the van der Waals interacting flat films [2]. Two different regimes (filling and growing) for the wetting film evolution were observed as a function of the chemical potential offset δμ. The filling regime exhibits a δμ-3/4 dependence for the adsorption of the liquid film into nanocavity; a significant enhancement compared to the flat surface. These results qualitatively confirm the theoretically predicted increase of the wetting exponent for the curved surface. However, quantitatively, the measured exponent for the paraboloid-like cavity is considerably lower than the predicted value [3]. *C. T. Black et al, Appl. Phys. Lett., 79, 409, (2001). *O. Gang et al, M. Fukuto, P.Huber, P.Pershan, Coll. and Surf. A 206, 293, 2002 *Rascon, C. and A.O. Parry, Nature, 407: p. 986 (2000); Robbins, M.O et al Phys. Rev. A, 43(8), 4344 (1991).

  8. Nano-optics with single quantum systems.

    PubMed

    Hecht, Bert

    2004-04-15

    This paper reviews the recent progress in using single quantum systems, here mainly single fluorescent molecules, as local probes for nano-optical field distributions. We start by discussing the role of the absorption cross-section for the spatial resolution attainable in such experiments and its behaviour for different environmental conditions. It is shown that the spatial distribution of field components in a high-numerical aperture laser focus can be mapped with high precision using single fluorescent molecules embedded in a thin polymer film on glass. With this proof-of-principle experiment as a starting point, the possibility of mapping strongly confined and enhanced nano-optical fields close to material structures, e.g. sharp metal tips, is discussed. The mapping of the spatial distribution of the enhanced field at an etched gold tip using a single molecule is presented as an example. Energy transfer effects and quenching are identified as possible artefacts in this context. Finally, it is demonstrated that the local quenching at a sharp metal structure nevertheless can be exploited as a novel contrast mechanism for ultrahigh-resolution optical microscopy with single-molecule sensitivity.

  9. Nano-encapsulation of fish oil in nano-liposomes and its application in fortification of yogurt.

    PubMed

    Ghorbanzade, Tahere; Jafari, Seid Mahdi; Akhavan, Sahar; Hadavi, Roxana

    2017-02-01

    Fish oils have many dietary benefits, but due to their strong odors and rapid deterioration, their application in food formulations is limited. For these reasons, nano-liposome was used to nano-encapsulate fish oil in this study and encapsulated fish oil was utilized in fortifying yogurt. Physicochemical properties of produced yogurt including pH, acidity, syneresis, fatty acid composition, peroxide value as well as sensory tests were investigated during three weeks storage at 4°C. Nano-liposome encapsulation resulted in a significant reduction in acidity, syneresis and peroxide value. The results of gas chromatography analyses revealed that after 21days storage, yogurt fortified with nano-encapsulated fish oil had a higher DHA and EPA contents than yogurt containing free fish oil. Overall, the results of this study indicates that adding nano-encapsulated fish oil into yogurt gave closer characteristics to control sample in terms of sensory characteristics than yogurt fortified with free fish oil.

  10. A large area nano-gap interdigitated electrode array on a polymer substrate as a disposable nano-biosensor

    NASA Astrophysics Data System (ADS)

    Shim, Joon S.; Rust, Michael J.; Ahn, Chong H.

    2013-03-01

    A low-cost nano-gap interdigitated electrode array (IDA) on a polymer substrate has been developed to realize a disposable nano-biosensor for biochemical clinical analysis. Utilizing the common instruments for optical lithography, nano-scale features were fabricated on a thermoplastic polymer to produce an electrochemical nano-biosensor in a disposable format. The IDA was realized on a 3-inch cyclo-olefin copolymer wafer, which illustrates the utility of our fabrication technique as a large-area nanofabrication process for a polymer using low temperature processes. In order to demonstrate the use of the sensor for lab-on-a-chip applications, the developed IDA was integrated with a microfluidic channel and applied for the electrochemical detection of poly-aminophenol with 10-8 M detection limit. The results indicate the developed fabrication technique is suitable for the inexpensive mass fabrication of highly sensitive nano-biosensors for disposable applications.

  11. Structural evolution of Ag-Cu nano-alloys confined between AlN nano-layers upon fast heating.

    PubMed

    Janczak-Rusch, J; Chiodi, M; Cancellieri, C; Moszner, F; Hauert, R; Pigozzi, G; Jeurgens, L P H

    2015-11-14

    The structural evolution of a Ag-Cu/AlN nano-multilayer (NML), as prepared by magnetron-sputtering on a α-Al2O3 substrate, was monitored during fast heating by real-time in situ XRD analysis (at the synchrotron), as well as by ex situ microstructural analysis using SEM, XPS and in-house XRD. The as-deposited NML is constituted of alternating nano-layers (thickness ≈ 10 nm) of a chemically inert AlN barrier and a eutectic Ag-Cu(40at%) nano-alloy. The nano-alloy in the as-deposited state is composed of a fcc matrix of Ag nano-grains (≈6 nm), which are supersaturated by Cu, and some smaller embedded Cu rich nano-grains (≈4 nm). Heating up to 265 °C activates segregation of Cu out of the supersaturated Ag nano-grains phase, thus initiating phase separation. At T > 265 °C, the phase-separated Cu metal partially migrates to the top NML surface, thereby relaxing thermally-accumulated compressive stresses in the confined alloy nano-layers and facilitating grain coarsening of (still confined) phase-separated nano-crystallites. Further heating and annealing up to 420 °C results in complete phase separation, forming extended Ag and Cu domains with well-defined coherent Ag/AlN interfaces. The observed outflow of Cu well below the eutectic melting point of the bulk Ag-Cu alloy might provide new pathways for designing low-temperature nano-structured brazing materials.

  12. Current HPLC Methods for Assay of Nano Drug Delivery Systems.

    PubMed

    Tekkeli, Serife Evrim Kepekci; Kiziltas, Mustafa Volkan

    2016-12-22

    In nano drug formulations the mechanism of release is a critical process to recognize controlled and targeted drug delivery systems. In order to gain high bioavailability and specificity from the drug to reach its therapeutic goal, the active substance must be loaded into the nanoparticles efficiently. Therefore, the amount in biological fluids or tissues and the remaining amount in nano carriers are very important parameters to understand the potential of the nano drug delivery systems. For this aim, suitable and validated quantitation methods are required to determine released drug concentrations from nano pharmaceutical formulations. HPLC (High Performance Liquid Chromatography) is one of the most common techniques used for determination of released drug content out of nano drug formulations, in different physical conditions, over different periods of time. Since there are many types of HPLC methods depending on detector and column types, it is a challenge for the researchers to choose a suitable method that is simple, fast and validated HPLC techniques for their nano drug delivery systems. This review's goal is to compare HPLC methods that are currently used in different nano drug delivery systems in order to provide detailed and useful information for researchers.

  13. Nano-patterning and single electron tunnelling using STM

    NASA Astrophysics Data System (ADS)

    Hu, Xiaoming; Sarid, D.; von Blanckenhagen, P.

    1999-06-01

    A scanning tunnelling microscope with a gold tip was used to create clusters and form nano-dots, lines and corrals on a clean stepped Si(111) surface by applying a series of bias pulses to the tip-sample tunnelling junction. Nano-dots with diameters as small as a few nm can be realized. By decreasing the distances between nano-dots, it is possible to create continuous nano-lines of a few nm wide and over a few hundred nm long, which can be used as connections between micro- and nano-electronic components. A nano-corral of about 40 nm in diameter formed by many Au dots of a few nm in diameter each was also created on the Si(111) surface. Single electron tunnelling effects through nano-dots were studied and it was found that `Coulomb staircases' can be observed in the I-V (current-voltage) curve at room temperature through an Au tip-Au cluster-Si substrate double junction system.

  14. Nano-Satellite Secondary Spacecraft on Deep Space Missions

    NASA Technical Reports Server (NTRS)

    Klesh, Andrew T.; Castillo-Rogez, Julie C.

    2012-01-01

    NanoSat technology has opened Earth orbit to extremely low-cost science missions through a common interface that provides greater launch accessibility. They have also been used on interplanetary missions, but these missions have used one-off components and architectures so that the return on investment has been limited. A natural question is the role that CubeSat-derived NanoSats could play to increase the science return of deep space missions. We do not consider single instrument nano-satellites as likely to complete entire Discovery-class missions alone,but believe that nano-satellites could augment larger missions to significantly increase science return. The key advantages offered by these mini-spacecrafts over previous planetary probes is the common availability of advanced subsystems that open the door to a large variety of science experiments, including new guidance, navigation and control capabilities. In this paper, multiple NanoSat science applications are investigated, primarily for high risk/high return science areas. We also address the significant challenges and questions that remain as obstacles to the use of nano-satellites in deep space missions. Finally, we provide some thoughts on a development roadmap toward interplanetary usage of NanoSpacecraft.

  15. Nano-composites for water remediation: a review.

    PubMed

    Tesh, Sarah J; Scott, Thomas B

    2014-09-17

    As global populations continue to increase, the pressure on water supplies will inevitably intensify. Consequently the international need for more efficient and cost effective water remediation technologies will also rise. The introduction of nano-technology into the industry may represent a significant advancement and zero-valent iron nano-particles (INPs) have been thoroughly studied for potential remediation applications. However, the application of water dispersed INP suspensions is limited and somewhat contentious on the grounds of safety, whilst INP reaction mechanisms, transport properties and ecotoxicity are areas still under investigation. Theoretically, the development of nano-composites containing INPs to overcome these issues provides the logical next step for developing nano-materials that are better suited to wide application across the water industry. This review provides an overview of the range of static, bulk nano-composites containing INPs being developed, whilst highlighting the limitations of individual solutions, overall classes of technology, and lack of comparative testing for nano-composites. The review discusses what further developments are needed to optimize nano-composite water remediation systems to subsequently achieve commercial maturity.

  16. The Nano-Micro Interface: Bridging the Micro and Nano Worlds

    NASA Astrophysics Data System (ADS)

    Fecht, Hans-Jörg; Werner, Matthias

    2004-12-01

    Two exciting worlds of science and technology - the nano and micro dimensions. The former is a booming new field of research, the latter the established size range for electronics, and for mutual technological benefit and future commercialization, suitable junctions need to be found. Functional nanostructures such as DNA computers, sensors, neural interfaces, nanooptics or molecular electronics need to be wired to their 'bigger' surroundings. Coming from the opposite direction, microelectronics have experienced an unprecedented miniaturization drive in the last decade, pushing ever further down through the micro size scale towards submicron circuitry. Bringing these two worlds together is a new interdisciplinary challenge for scientists and engineers alike - recognized and substantially funded by the European Commission and other major project initiators worldwide. This book offers a wide range of information from technologies to materials and devices as well as from research to administrative know-how collected by the editors from renowned key members of the nano/micro community.

  17. The Nano-Micro Interface: Bridging the Micro and Nano Worlds

    NASA Astrophysics Data System (ADS)

    Fecht, Hans-Jörg; Werner, Matthias

    2003-09-01

    Two exciting worlds of science and technology - the nano and micro dimensions. The former is a booming new field of research, the latter the established size range for electronics, and for mutual technological benefit and future commercialization, suitable junctions need to be found. Functional nanostructures such as DNA computers, sensors, neural interfaces, nanooptics or molecular electronics need to be wired to their 'bigger' surroundings. Coming from the opposite direction, microelectronics have experienced an unprecedented miniaturization drive in the last decade, pushing ever further down through the micro size scale towards submicron circuitry. Bringing these two worlds together is a new interdisciplinary challenge for scientists and engineers alike - recognized and substantially funded by the European Commission and other major project initiators worldwide. This book offers a wide range of information from technologies to materials and devices as well as from research to administrative know-how collected by the editors from renowned key members of the nano/micro community.

  18. Orientated Nano-Composites: Relationships Between Nano-Structure and Mechanical Properties

    DTIC Science & Technology

    2004-11-01

    reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of...a range of modifiers, including organoclays , silica nanoparticles and carbon nanotubes. The mechanical and fracture properties of these materials have...Std Z39-18 2 Abstract Epoxy nano-composites have been manufactured using a range of modifiers, including organoclays , silica nanoparticles and

  19. Synergy among binary (MWNT, SLG) nano-carbons in polymer nano-composites: a Raman study

    NASA Astrophysics Data System (ADS)

    Xu, Peng; Loomis, James; King, Ben; Panchapakesan, Balaji

    2012-08-01

    Load transfer and mechanical strength of reinforced polymers are fundamental to developing advanced composites. This paper demonstrates enhanced load transfer and mechanical strength due to synergistic effects in binary mixtures of nano-carbon/polymer composites. Different compositional mixtures (always 1 wt% total) of multi-wall carbon nanotubes (MWNTs) and single-layer graphene (SLG) were mixed in polydimethylsiloxane (PDMS), and effects on load transfer and mechanical strength were studied using Raman spectroscopy. Significant shifts in the G-bands were observed both in tension and compression for single as well as binary nano-carbon counterparts in polymer composites. Small amounts of MWNT0.1 dispersed in SLG0.9/PDMS samples (subscripts represent weight percentage) reversed the sign of the Raman wavenumbers from positive to negative values demonstrating reversal of lattice stress. A wavenumber change from 10 cm-1 in compression to 10 cm-1 in tension, and an increase in elastic modulus of ˜103% was observed for MWNT0.1SLG0.9/PDMS with applied uniaxial tension. Extensive scanning electron microscopy revealed the bridging of MWNT between two graphene plates in polymer composites. Mixing small amounts of MWNTs in SLG/PDMS eliminated the previously reported compressive deformation of SLG and significantly enhanced load transfer and mechanical strength of composites in tension. The orientation order of MWNT with application of uniaxial tensile strain directly affected the shift in Raman wavenumbers (2D-band and G-band) and load transfer. It is observed that the cooperative behavior of binary nano-carbons in polymer composites resulted in enhanced load transfer and mechanical strength. Such binary compositions could be fundamental to developing advanced composites such as nano-carbon based mixed dimensional systems.

  20. Knotting of linear DNA in nano-slits and nano-channels: a numerical study.

    PubMed

    Orlandini, Enzo; Micheletti, Cristian

    2013-03-01

    The amount and type of self-entanglement of DNA filaments is significantly affected by spatial confinement, which is ubiquitous in biological systems. Motivated by recent advancements in single DNA molecule experiments based on nanofluidic devices and by the introduction of algorithms capable of detecting knots in open chains, we investigate numerically the entanglement of linear, open DNA chains confined inside nano-slits. The results regard the abundance, type, and length of occurring knots and are compared with recent findings for DNA inside nano-channels. In both cases, the width of the confining region, D, spans the 30 nm-1 μm range and the confined DNA chains are 1-4 μm long. It is found that the knotting probability is maximum for slit widths in the 70-100 nm range. However, over the considered DNA contour lengths, the maximum incidence of knots remains below 20%, while for channel confinement it tops 50%. Further differences of the entanglement are seen for the average contour length of the knotted region, which drops significantly below D ~100 nm for channel-confinement, while it stays approximately constant for slit-like confinement. These properties ought to reverberate in different kinetic properties of linear DNA depending on confinement and could be detectable experimentally or exploitable in nano-technological applications.

  1. Nano bubbles in liquid of a noble-gas mixture.

    PubMed

    Yamamoto, Takenori; Ohnishi, Shuhei

    2010-02-07

    Large-scale molecular dynamics (MD) simulations with over one million atoms are used to investigate nano bubbles in Ar-Ne liquid. The simulations demonstrate cavitations in the stretched liquid, and bubble creation and collapse. We find that a small cavity created in the stretched liquid spontaneously transforms into a nano bubble with the homogeneous vapor region. The equilibrium spherical bubble of 11.4 nm in radius is obtained after the long-time MD run. The surface tension of the nano bubble is found to be larger than that of the flat surface.

  2. Carbon nanotube-based nano-fluidic devices

    NASA Astrophysics Data System (ADS)

    Masoud Seyyed Fakhrabadi, Mir; Rastgoo, Abbas; Taghi Ahmadian, Mohammad

    2014-02-01

    The paper investigates the influences of fluid flow on static and dynamic behaviours of electrostatically actuated carbon nanotubes (CNTs) using strain gradient theory. This nonclassical elasticity theory is applied in order to obtain more accurate results possessing higher agreement with the experimental data. The effects of various fluid parameters such as the fluid viscosity, velocity, mass and temperature on the pull-in properties of the CNTs with two cantilever and doubly clamped boundary conditions are studied. The results reveal the applicability of the proposed nano-system as nano-valves or nano-fluidic sensors.

  3. Micro and Nano-mediated 3D Cardiac Tissue Engineering

    DTIC Science & Technology

    2009-10-01

    Micro and Nano -mediated 3D Cardiac Tissue Engineering PRINCIPAL INVESTIGATOR:  Rashid Bashir, PhD, PI  Brian Cunningham, PhD, co-PI  Hyunjoon...SUBTITLE Micro and Nano -mediated 3D Cardiac Tissue Engineering 5a. CONTRACT NUMBER 5b. GRANT NUMBER W81XWH-08-1-0701 5c. PROGRAM ELEMENT...Optical  Characterization (Cunningham) Mechano‐Biology  of Cardiac Cells (Saif) Micro / Nano ‐ Medicated  Cardiac Tissue  Engineering Dr. M. Gibb, Head of

  4. Surface/Fluid Interactions in Micro and Nano-Channels

    DTIC Science & Technology

    2007-05-15

    05-2007 Final 01-01-2004 - 31-12-2006 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER SURFACE/FLUID INTERACTIONS IN MICRO & NANO -CHANNELS 5b. GRANT NUMBER...NOTES 14. ABSTRACT This research project investigates the dynamics of surface/fluid interactions that occur in micro - and nano -cnanneis. For example...ANSI Std. Z39.18 SURFACE/FLUID INTERACTIONS IN MICRO & NANO -CHANNELS AFSOR FA9950-04-0106 Carl D. Meinhart Department of Mechanical Engineering

  5. Method of producing nano-scaled inorganic platelets

    DOEpatents

    Zhamu, Aruna; Jang, Bor Z.

    2012-11-13

    The present invention provides a method of exfoliating a layered material (e.g., transition metal dichalcogenide) to produce nano-scaled platelets having a thickness smaller than 100 nm, typically smaller than 10 nm. The method comprises (a) dispersing particles of a non-graphite laminar compound in a liquid medium containing therein a surfactant or dispersing agent to obtain a stable suspension or slurry; and (b) exposing the suspension or slurry to ultrasonic waves at an energy level for a sufficient length of time to produce separated nano-scaled platelets. The nano-scaled platelets are candidate reinforcement fillers for polymer nanocomposites.

  6. Stoffenmanager Nano version 1.0: a web-based tool for risk prioritization of airborne manufactured nano objects.

    PubMed

    Van Duuren-Stuurman, Birgit; Vink, Stefan R; Verbist, Koen J M; Heussen, Henri G A; Brouwer, Derk H; Kroese, Dinant E D; Van Niftrik, Maikel F J; Tielemans, Erik; Fransman, Wouter

    2012-07-01

    Stoffenmanager Nano (version 1.0) is a risk-banding tool developed for employers and employees to prioritize health risks occurring as a result of exposure to manufactured nano objects (MNOs) for a broad range of worker scenarios and to assist implementation of control measures to reduce exposure levels. In order to prioritize the health risks, the Stoffenmanager Nano combines the available hazard information of a substance with a qualitative estimate of potential for inhalation exposure. The development of the Stoffenmanager Nano started with a review of the available literature on control banding. Input parameters for the hazard assessment of MNOs were selected based on the availability of these parameters in, for instance, Safety Data Sheets or product information sheets. The conceptual exposure model described by Schneider et al. (2011) was used as the starting point for exposure banding. During the development of the Stoffenmanager Nano tool, the precautionary principle was applied to deal with the uncertainty regarding hazard and exposure assessment of MNOs. Subsequently, the model was converted into an online tool (http://nano.stoffenmanager.nl), tested, and reviewed by a number of companies. In this paper, we describe the Stoffenmanager Nano. This tool offers a practical approach for risk prioritization in exposure situations where quantitative risk assessment is currently not possible. Updates of this first version are anticipated as more data become available in the future.

  7. Effects of micro-nano and non micro-nano MSWI ashes addition on MSW anaerobic digestion.

    PubMed

    Lo, H M; Chiu, H Y; Lo, S W; Lo, F C

    2012-06-01

    This study aims at investigating the effects of micro-nano municipal solid waste (MSW) incinerator (MSWI) fly ash (FA) and bottom ash (BA) on the MSW anaerobic digestion. Results showed that suitable micro-nano and non micro-nano MSWI ashes addition (FA/MSW 3, 6, 18 and 30 g g(-1) VS and BA/MSW 12, 36, 60 and 120 g g(-1) VS) could enhance the biogas production compared to the control. It was particularly found to have the highest biogas production at the micro-nano MSWI BA/MSW ratio of 36 g g(-1) VS (∼193 mL g(-1) VS MSW, ∼3.5 times to the control). Micro-nano MSWI FA and BA added bioreactors had the higher biogas production than the corresponding non micro-nano MSWI FA and BA added ones. Suitable MSWI ashes addition could improve the biogas production due to the released metals levels suitable for the MSW anaerobic digestion particularly found in the micro-nano added bioreactors.

  8. Photosynthetic Machineries in Nano-Systems

    PubMed Central

    Nagy, László; Magyar, Melinda; Szabó, Tibor; Hajdu, Kata; Giotta, Livia; Dorogi, Márta; Milano, Francesco

    2014-01-01

    Photosynthetic reaction centres are membrane-spanning proteins, found in several classes of autotroph organisms, where a photoinduced charge separation and stabilization takes place with a quantum efficiency close to unity. The protein remains stable and fully functional also when extracted and purified in detergents thereby biotechnological applications are possible, for example, assembling it in nano-structures or in optoelectronic systems. Several types of bionanocomposite materials have been assembled by using reaction centres and different carrier matrices for different purposes in the field of light energy conversion (e.g., photovoltaics) or biosensing (e.g., for specific detection of pesticides). In this review we will summarize the current status of knowledge, the kinds of applications available and the difficulties to be overcome in the different applications. We will also show possible research directions for the close future in this specific field. PMID:24678673

  9. Hierarchical Micro-Nano Coatings by Painting

    NASA Astrophysics Data System (ADS)

    Kirveslahti, Anna; Korhonen, Tuulia; Suvanto, Mika; Pakkanen, Tapani A.

    2016-03-01

    In this paper, the wettability properties of coatings with hierarchical surface structures and low surface energy were studied. Hierarchically structured coatings were produced by using hydrophobic fumed silica nanoparticles and polytetrafluoroethylene (PTFE) microparticles as additives in polyester (PES) and polyvinyldifluoride (PVDF). These particles created hierarchical micro-nano structures on the paint surfaces and lowered or supported the already low surface energy of the paint. Two standard application techniques for paint application were employed and the presented coatings are suitable for mass production and use in large surface areas. By regulating the particle concentrations, it was possible to modify wettability properties gradually. Highly hydrophobic surfaces were achieved with the highest contact angle of 165∘. Dynamic contact angle measurements were carried out for a set of selected samples and low hysteresis was obtained. Produced coatings possessed long lasting durability in the air and in underwater conditions.

  10. Nano-ADEPT Aeroloads Wind Tunnel Test

    NASA Technical Reports Server (NTRS)

    Smith, Brandon; Cassell, A.; Yount, B.; Kruger, C.; Brivkalns, C.; Makino, A.; Zarchi, K.; McDaniel, R.; Venkatapathy, E.; Swanson, G.

    2015-01-01

    Analysis completed since the test suggests that all test objectives were met– This claim will be verified in the coming weeks as the data is examined further– Final disposition of test objective success will be documented in a final reportsubmitted to NASA stakeholders (early August 2015)– Expect conference paper in early 2016• Data products and observations made during testing will be used to refinecomputational models of Nano-ADEPT• Carbon fabric relaxed from its pre-test state during the test– System-level tolerance for relaxation will be driven by destination-specific andmission-specific aerothermal and aerodynamic requirements• Bonus experiment of asymmetric shape demonstrates that an asymmetricdeployable blunt body can be used to generate measureable lift– With a strut actuation system and a robust GN&C algorithm, this effect could beused to steer a blunt body at hypersonic speeds to aid precision landing

  11. Nano-Fabricated Gratings for Electrons

    NASA Astrophysics Data System (ADS)

    Gronniger, Glen; Savas, Tim; Batelaan, Herman

    2005-05-01

    We explore the lower energy range for electron diffraction from a Au and Pd coated nano-fabricated transmission grating. This has the promise of providing a route to the lowest energy electron interferometer currently possible. Starting at 1000 eV we get well resolved diffraction peaks. As 60 eV electron energy is approached the diffraction peaks broaden to the extent that they are hard to resolve. We attribute this to an effective loss of transverse coherence length. We show that the broadening and coherence loss can be modeled with a path integral calculation where the essential ingredient is a random spatially varying potential with a typical length scale of 200 nm. The effect of other coatings, such as Ni, is investigated and indicates that lower electron energies can be reached. Work supported by NSF, DOD-EPSCoR.

  12. Block copolymer structures in nano-pores

    NASA Astrophysics Data System (ADS)

    Pinna, Marco; Guo, Xiaohu; Zvelindovsky, Andrei

    2010-03-01

    We present results of coarse-grained computer modelling of block copolymer systems in cylindrical and spherical nanopores on Cell Dynamics Simulation. We study both cylindrical and spherical pores and systematically investigate structures formed by lamellar, cylinders and spherical block copolymer systems for various pore radii and affinity of block copolymer blocks to the pore walls. The obtained structures include: standing lamellae and cylinders, ``onions,'' cylinder ``knitting balls,'' ``golf-ball,'' layered spherical, ``virus''-like and mixed morphologies with T-junctions and U-type defects [1]. Kinetics of the structure formation and the differences with planar films are discussed. Our simulations suggest that novel porous nano-containers can be formed by confining block copolymers in pores of different geometries [1,2]. [4pt] [1] M. Pinna, X. Guo, A.V. Zvelindovsky, Polymer 49, 2797 (2008).[0pt] [2] M. Pinna, X. Guo, A.V. Zvelindovsky, J. Chem. Phys. 131, 214902 (2009).

  13. Nano-encapsulated PCM via Pickering Emulsification

    NASA Astrophysics Data System (ADS)

    Wang, Xuezhen; Zhang, Lecheng; Yu, Yi-Hsien; Jia, Lisi; Sam Mannan, M.; Chen, Ying; Cheng, Zhengdong

    2015-08-01

    We designed a two-step Pickering emulsification procedure to create nano-encapsulated phase changing materials (NEPCMs) using a method whose simplicity and low energy consumption suggest promise for scale-up and mass production. Surface-modified amphiphilic zirconium phosphate (ZrP) platelets were fabricated as the Pickering emulsifiers, nonadecane was chosen as the core phase change material (PCM), and polystyrene, the shell material. The resultant capsules were submicron in size with remarkable uniformity in size distribution, which has rarely been reported. Differential scanning calorimetry (DSC) characterization showed that the capsulation efficiency of NEPCMs, and they were found to be thermal stable, as characterized by the DSC data for the sample after 200 thermal cycles. NEPCMs exhibit superior mechanical stability and mobility when compared with the well-developed micro-encapsulated phase change materials (MEPCMs). NEPCMs find useful applications in thermal management, including micro-channel coolants; solar energy storage media; building temperature regulators; and thermal transfer fabrics.

  14. NGC1068: a nano-diamond factory?

    NASA Astrophysics Data System (ADS)

    Rouan, D.; Gratadour, D.; Clénet, Y.; Gendron, E.

    2004-12-01

    We present recent Adaptive Optics images in Ks, L and M bands of NGC 1068, obtained with NAOS-CONICA on VLT. The very peculiar structure of four parallel elongated nodules unveiled by deconvolution underlines a strong correlation with the radio jet which appears as a major actor to shape the NLR. We the Ks-L and L-M color ratio reveal dust at a very high temperature (about 500-600 K) up to 70 pc north of the nucleus. We explore several mechanisms to explain the color temperature. We favour the transient heating of Very Small Grains as the most efficient process to produce high color temperature. Since nano-diamonds are preferentially formed in UV field or in shocks, and that they reproduce nicely the observed color temperature, we propose that they indeed represent a major component of the VSG population.

  15. Transdermal drug delivery: from micro to nano

    NASA Astrophysics Data System (ADS)

    Pegoraro, Carla; MacNeil, Sheila; Battaglia, Giuseppe

    2012-03-01

    Delivery across skin offers many advantages compared to oral or intravenous routes of drug administration. Skin however is highly impermeable to most molecules on the basis of size, hydrophilicity, lipophilicity and charge. For this reason it is often necessary to temporarily alter the barrier properties of skin for effective administration. This can be done by applying chemical enhancers, which alter the lipid structure of the top layer of skin (the stratum corneum, SC), by applying external forces such as electric currents and ultrasounds, by bypassing the stratum corneum via minimally invasive microneedles or by using nano-delivery vehicles that can cross and deliver their payload to the deeper layers of skin. Here we present a critical summary of the latest technologies used to increase transdermal delivery.

  16. Novel nano bearings constructed by physical adsorption

    NASA Astrophysics Data System (ADS)

    Zhang, Yongbin

    2015-09-01

    The paper proposes a novel nano bearing formed by the physical adsorption of the confined fluid to the solid wall. The bearing is formed between two parallel smooth solid plane walls sliding against one another, where conventional hydrodynamic lubrication theory predicted no lubricating effect. In this bearing, the stationary solid wall is divided into two subzones which respectively have different interaction strengths with the lubricating fluid. It leads to different physical adsorption and slip properties of the lubricating fluid at the stationary solid wall respectively in these two subzones. It was found that a significant load-carrying capacity of the bearing can be generated for low lubricating film thicknesses, because of the strong physical adsorption and non-continuum effects of the lubricating film.

  17. Tunable nano dispersed LC based patch antenna

    NASA Astrophysics Data System (ADS)

    Karim, Afaque; Yadav, Harsh; Ahmad, Shakeb

    2015-06-01

    This paper presents Patch antenna based on pure and Nano dispersed liquid crystals (LCs) for earth and space applications. Patch antenna are one of the most attractive antennas designed for RF frequency. To fulfill the demand of modern antenna i.e. tunability, a design of LC based patch antenna with optimum frequency of 15 GHz is investigated. In this design, NLC and ZnO doped NLC were used as a dielectric substrate. Its dielectric permittivity was controlled by biasing voltage. The dielectric properties of the 4-Cyano-4' -pentylbiphenyl (5CB) nematic liquid crystal (NLC), and NLC doped with Zinc oxide (ZnO) Nanoparticles was studied at room temperature. The concentration of doping material was 0.5% by w.t. in ZnO. Results shows that dielectric parameters are strong function of frequency and applied bias voltage. Moreover, Using doped NLC as dielectric substrate one gets more tunability or shift in resonant frequency in the proposed geometry.

  18. Novel nano bearings constructed by physical adsorption

    PubMed Central

    Zhang, Yongbin

    2015-01-01

    The paper proposes a novel nano bearing formed by the physical adsorption of the confined fluid to the solid wall. The bearing is formed between two parallel smooth solid plane walls sliding against one another, where conventional hydrodynamic lubrication theory predicted no lubricating effect. In this bearing, the stationary solid wall is divided into two subzones which respectively have different interaction strengths with the lubricating fluid. It leads to different physical adsorption and slip properties of the lubricating fluid at the stationary solid wall respectively in these two subzones. It was found that a significant load-carrying capacity of the bearing can be generated for low lubricating film thicknesses, because of the strong physical adsorption and non-continuum effects of the lubricating film. PMID:26412488

  19. "Nano" Scale Biosignatures and the Search for Extraterrestrial Life

    NASA Technical Reports Server (NTRS)

    Oehler, D. Z.; Robert, F.; Meibom, A.; Mostefaoui, S.; Selo, M.; Walter, M. R.; Sugitani, K.; Allwood, A.; Mimura, K.; Gibson, E. K.

    2008-01-01

    A critical step in the search for remnants of potential life forms on other planets lies in our ability to recognize indigenous fragments of ancient microbes preserved in some of Earth's oldest rocks. To this end, we are building a database of nano-scale chemical and morphological characteristics of some of Earth's oldest organic microfossils. We are primarily using the new technology of Nano-Secondary ion mass spectrometry (NanoSIMS) which provides in-situ, nano-scale elemental analysis of trace quantities of organic residues. The initial step was to characterize element composition of well-preserved, organic microfossils from the late Proterozoic (0.8 Ga) Bitter Springs Formation of Australia. Results from that work provide morphologic detail and nitrogen/carbon ratios that appear to reflect the well-established biological origin of these 0.8 Ga fossils.

  20. MULTIFUNCTIONAL NANO-BIO MATERIALS WITHIN CELLULAR MACHINERY.

    PubMed

    Rozhkova, E A; Ulasov, I V; Kim, D-H; Dimitrijevic, N M; Novosad, V; Bader, S D; Lesniak, M S; Rajh, T

    2011-08-01

    Functional nanoscale materials that possess specific physical or chemical properties can leverage energy transduction in vivo. Once these materials integrate with biomolecules they combine physical properties of inorganic material and the biorecognition capabilities of bio-organic moieties. Such nano-bio hybrids can be interfaced with living cells, the elementary functional units of life. These nano-bio systems are capable of bio-manipulation or actuation via altering intracellular biochemical pathways. Thus, nano-bio conjugates are appealing for a wide range of applications from the life sciences and nanomedicine to catalysis and clean energy production. Here we highlight recent progress in our efforts to develop smart nano-bio hybrid materials, and to study their performance within cellular machinery under application of external stimuli, such as light or magnetic fields.

  1. Nano-fiber diameters as liquid concentration sensors

    NASA Astrophysics Data System (ADS)

    Chyad, Radhi M.; Mat Jafri, Mohd Zubir; Ibrahim, Kamarulazizi

    2013-05-01

    Manufacturing technologies of nano-fiber sensors offer a number of approved properties of optical fiber sensors utilized in various sensory applications. The nano-fiber sensor is utilized to sense the difference in the concentration of D-glucose in double-distilled deionized water and to measure the refractive index (RI) of a sugar solution. Our proposed method exhibited satisfactory capability based on bimolecular interactions in the biological system. The response of the nano-fiber sensors indicates a different kind of interaction among various groups of AAs. These results can be interpreted in terms of solute-solute and solute-solvent interactions and the structure making or breaking ability of solutes in the given solution. This study utilized spectra photonics to measure the transmission of light through different concentrations of sugar solution, employing cell cumber and nano-optical fibers as sensors.

  2. Effect of micro/nano-particles in cavitation erosion.

    PubMed

    Li, Y J; Chen, H S; Chen, D R; Wang, J D

    2009-02-01

    The tests in de-ionized water with micro/nano CeO2 particles are carried out to study the effect of the micro/nano particles in inception of cavitation erosion. The existence of micro/nano particles is found to be the requisite factor and the degree of cavitation erosion is related to the sizes of the particles. Particles in the micro/nano scale may act as the transporters of micro bubbles to keep or get close to the solid surface together and the pressure fluctuation induced by the surface roughness causes the collapse of bubbles and erosion of the surface. Discrete phase models are employed to simulation the moving tracks of the particles. The sizes of the particles affect their capabilities of keeping and getting close to the surface. The effect of the particles of a certain size in cavitation erosion is determined by the combinational action of the two.

  3. Potential Nano-Enabled Environmental Applications for Radionuclides

    EPA Pesticide Factsheets

    This document provides information about nanotechnology materials and processes that may be applicable when cleaning up radioactively contaminated sites or materials, and presents a snapshot of lessons learned in nano-science and engineering.

  4. Near-field NanoThermoMechanical memory

    SciTech Connect

    Elzouka, Mahmoud; Ndao, Sidy

    2014-12-15

    In this letter, we introduce the concept of NanoThermoMechanical Memory. Unlike electronic memory, a NanoThermoMechanical memory device uses heat instead of electricity to record, store, and recover data. Memory function is achieved through the coupling of near-field thermal radiation and thermal expansion resulting in negative differential thermal resistance and thermal latching. Here, we demonstrate theoretically via numerical modeling the concept of near-field thermal radiation enabled negative differential thermal resistance that achieves bistable states. Design and implementation of a practical silicon based NanoThermoMechanical memory device are proposed along with a study of its dynamic response under write/read cycles. With more than 50% of the world's energy losses being in the form of heat along with the ever increasing need to develop computer technologies which can operate in harsh environments (e.g., very high temperatures), NanoThermoMechanical memory and logic devices may hold the answer.

  5. National solar technology roadmap: Nano-architecture PV

    SciTech Connect

    Zhang, Yong

    2007-06-01

    This roadmap addresses nano-architecture solar cells that use nanowires, nanotubes, and nanocrystals, including single-component, core-shell, embedded nanowires or nanocrystals either as absorbers or transporters.

  6. Synthesis of mesoporous nano-hydroxyapatite by using zwitterions surfactant

    EPA Science Inventory

    Mesoporous nano-hydroxyapatite (mn-HAP) was successfully synthesized via a novel micelle-templating method using lauryl dimethylaminoacetic acid as zwitterionic surfactant. The systematic use of such a surfactant in combination with microwave energy inputenables the precise contr...

  7. Nano-JASMINE: current status and data output

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yukiyasu; Yano, Taihei; Gouda, Naoteru; Niwa, Yoshito; Murooka, Jyunpei; Yamada, Yoshiyuki; Sako, Nobutada; Nakasuka, Shin'ichi

    2010-07-01

    The current status of the Nano-JASMINE project is reported. Nano-JASMINE is a very small-sized (50 cm cubic form) satellite that is expected to carry out astrometric observations of nearby bright stars. The satellite will determine distances of more than 8000 stars by performing annual parallax measurements, which is the only direct method to measure the distance of an astronomical object. The mission is required to continue for more than two years to obtain reliable annual parallax measurements. In addition, Nano-JASMINE will serve as a preliminary to the main JASMINE mission. We expect that Nano-JASMINE will be launched in August 2011 from the Alcantara Space Center in Brazil using the Cyclone-4 rocket.

  8. Plasmonic nano-antenna a-Si:H solar cell.

    PubMed

    Di Vece, Marcel; Kuang, Yinghuan; van Duren, Stephan N F; Charry, Jamie M; van Dijk, Lourens; Schropp, Ruud E I

    2012-12-03

    In this work the effects of plasmonics, nano-focusing, and orthogonalization of carrier and photon pathways are simultaneously explored by measuring the photocurrents in an elongated nano-scale solar cell with a silver nanoneedle inside. The silver nanoneedles formed the support of a conformally grown hydrogenated amorphous silicon (a-Si:H) n-i-p junction around it. A spherical morphology of the solar cell functions as a nano-lens, focusing incoming light directly on the silver nanoneedle. We found that plasmonics, geometric optics, and Fresnel reflections affect the nanostructured solar cell performance, depending strongly on light incidence angle and polarization. This provides valuable insight in solar cell processes in which novel concepts such as plasmonics, elongated nanostructures, and nano-lenses are used.

  9. Nano-cone resistive memory for ultralow power operation.

    PubMed

    Kim, Sungjun; Jung, Sunghun; Kim, Min-Hwi; Kim, Tae-Hyeon; Bang, Suhyun; Cho, Seongjae; Park, Byung-Gook

    2017-03-24

    SiN x -based nano-structure resistive memory is fabricated by fully silicon CMOS compatible process integration including particularly designed anisotropic etching for the construction of a nano-cone silicon bottom electrode (BE). Bipolar resistive switching characteristics have significantly reduced switching current and voltage and are demonstrated in a nano-cone BE structure, as compared with those in a flat BE one. We have verified by systematic device simulations that the main cause of reduction in the performance parameters is the high electric field being more effectively concentrated at the tip of the cone-shaped BE. The greatly improved nonlinearity of the nano-cone resistive memory cell will be beneficial in the ultra-high-density crossbar array.

  10. A planar nano-positioner driven by shear piezoelectric actuators

    NASA Astrophysics Data System (ADS)

    Dong, W.; Li, H.; Du, Z.

    2016-08-01

    A planar nano-positioner driven by the shear piezoelectric actuators is proposed in this paper based on inertial sliding theory. The performance of the nano-positioner actuated by different driving signals is analyzed and discussed, e.g. the resolution and the average velocity which depend on the frequency, the amplitude and the wave form of the driving curves. Based on the proposed design, a prototype system of the nano-positioner is developed by using a capacitive sensor as the measurement device. The experiment results show that the proposed nano-positioner is capable of outputting two-dimensional motions within an area of 10 mm × 10 mm at a maximum speed of 0.25 mm/s. The corresponding resolution can be as small as 21 nm. The methodology outlined in this paper can be employed and extended to shear piezoelectric actuators involved in high precision positioning systems.

  11. Electrochemical micro/nano-machining: principles and practices.

    PubMed

    Zhan, Dongping; Han, Lianhuan; Zhang, Jie; He, Quanfeng; Tian, Zhao-Wu; Tian, Zhong-Qun

    2017-03-06

    Micro/nano-machining (MNM) is becoming the cutting-edge of high-tech manufacturing because of the increasing industrial demand for supersmooth surfaces and functional three-dimensional micro/nano-structures (3D-MNS) in ultra-large scale integrated circuits, microelectromechanical systems, miniaturized total analysis systems, precision optics, and so on. Taking advantage of no tool wear, no surface stress, environmental friendliness, simple operation, and low cost, electrochemical micro/nano-machining (EC-MNM) has an irreplaceable role in MNM. This comprehensive review presents the state-of-art of EC-MNM techniques for direct writing, surface planarization and polishing, and 3D-MNS fabrications. The key point of EC-MNM is to confine electrochemical reactions at the micro/nano-meter scale. This review will bring together various solutions to "confined reaction" ranging from electrochemical principles through technical characteristics to relevant applications.

  12. Near-field NanoThermoMechanical memory

    NASA Astrophysics Data System (ADS)

    Elzouka, Mahmoud; Ndao, Sidy

    2014-12-01

    In this letter, we introduce the concept of NanoThermoMechanical Memory. Unlike electronic memory, a NanoThermoMechanical memory device uses heat instead of electricity to record, store, and recover data. Memory function is achieved through the coupling of near-field thermal radiation and thermal expansion resulting in negative differential thermal resistance and thermal latching. Here, we demonstrate theoretically via numerical modeling the concept of near-field thermal radiation enabled negative differential thermal resistance that achieves bistable states. Design and implementation of a practical silicon based NanoThermoMechanical memory device are proposed along with a study of its dynamic response under write/read cycles. With more than 50% of the world's energy losses being in the form of heat along with the ever increasing need to develop computer technologies which can operate in harsh environments (e.g., very high temperatures), NanoThermoMechanical memory and logic devices may hold the answer.

  13. Visualization and processing of images in nano-resolution

    NASA Astrophysics Data System (ADS)

    Vozenilek, Vit; Pour, Tomas

    2017-02-01

    The paper aims to apply the methods of image processing which are widely used in Earth remote sensing for processing and visualization of images in nano-resolution because most of these images are currently analyzed only by an expert researcher without proper statistical background. Nano-resolution level may range from a resolution in picometres to the resolution of a light microscope that may be up to about 200 nanometers. Images in nano-resolution play an essential role in physics, medicine, and chemistry. Three case studies demonstrate different image visualization and image analysis approaches for different scales at the nano-resolution level. The results of case studies prove the suitability and applicability of Earth remote sensing methods for image visualization and processing for the nanoresolution level. It even opens new dimensions for spatial analysis at such an extreme spatial detail.

  14. Nano-cone resistive memory for ultralow power operation

    NASA Astrophysics Data System (ADS)

    Kim, Sungjun; Jung, Sunghun; Kim, Min-Hwi; Kim, Tae-Hyeon; Bang, Suhyung; Cho, Seongjae; Park, Byung-Gook

    2017-03-01

    SiN x -based nano-structure resistive memory is fabricated by fully silicon CMOS compatible process integration including particularly designed anisotropic etching for the construction of a nano-cone silicon bottom electrode (BE). Bipolar resistive switching characteristics have significantly reduced switching current and voltage and are demonstrated in a nano-cone BE structure, as compared with those in a flat BE one. We have verified by systematic device simulations that the main cause of reduction in the performance parameters is the high electric field being more effectively concentrated at the tip of the cone-shaped BE. The greatly improved nonlinearity of the nano-cone resistive memory cell will be beneficial in the ultra-high-density crossbar array.

  15. Engineered nano particles: Nature, behavior, and effect on the environment.

    PubMed

    Goswami, Linee; Kim, Ki-Hyun; Deep, Akash; Das, Pallabi; Bhattacharya, Satya Sundar; Kumar, Sandeep; Adelodun, Adedeji A

    2017-03-13

    Increased application of engineered nano particles (ENPs) in production of various appliances and consumer items is increasing their presence in the natural environment. Although a wide variety of nano particles (NPs) are ubiquitously dispersed in ecosystems, risk assessment guidelines to describe their ageing, direct exposure, and long-term accumulation characteristics are poorly developed. In this review, we describe what is known about the life cycle of ENPs and their impact on natural systems and examine if there is a cohesive relationship between their transformation processes and bio-accessibility in various food chains. Different environmental stressors influence the fate of these particles in the environment. Composition of solid media, pore size, solution chemistry, mineral composition, presence of natural organic matter, and fluid velocity are some environmental stressors that influence the transformation, transport, and mobility of nano particles. Transformed nano particles can reduce cell viability, growth and morphology, enhance oxidative stress, and damage DNA in living organisms.

  16. Probabilistic environmental risk assessment of five nanomaterials (nano-TiO2, nano-Ag, nano-ZnO, CNT, and fullerenes).

    PubMed

    Coll, Claudia; Notter, Dominic; Gottschalk, Fadri; Sun, Tianyin; Som, Claudia; Nowack, Bernd

    2016-01-01

    The environmental risks of five engineered nanomaterials (nano-TiO2, nano-Ag, nano-ZnO, CNT, and fullerenes) were quantified in water, soils, and sediments using probabilistic Species Sensitivity Distributions (pSSDs) and probabilistic predicted environmental concentrations (PECs). For water and soil, enough ecotoxicological endpoints were found for a full risk characterization (between 17 and 73 data points per nanomaterial for water and between 4 and 20 for soil) whereas for sediments, the data availability was not sufficient. Predicted No Effect Concentrations (PNECs) were obtained from the pSSD and used to calculate risk characterization ratios (PEC/PNEC). For most materials and environmental compartments, exposure and effect concentrations were separated by several orders of magnitude. Nano-ZnO in freshwaters and nano-TiO2 in soils were the combinations where the risk characterization ratio was closest to one, meaning that these are compartment/ENM combinations to be studied in more depth with the highest priority. The probabilistic risk quantification allows us to consider the large variability of observed effects in different ecotoxicological studies and the uncertainty in modeled exposure concentrations. The risk characterization results presented in this work allows for a more focused investigation of environmental risks of nanomaterials by consideration of material/compartment combinations where the highest probability for effects with predicted environmental concentrations is likely.

  17. Simple route for nano-hydroxyapatite properties expansion.

    PubMed

    Rojas, L; Olmedo, H; García-Piñeres, A J; Silveira, C; Tasic, L; Fraga, F; Montero, M L

    2015-10-20

    Simple surface modification of nano-hydroxyapatite, through acid-basic reactions, allows expanding the properties of this material. Introduction of organic groups such as hydrophobic alkyl chains, carboxylic acid, and amide or amine basic groups on the hydroxyapatite surface systematically change the polarity, surface area, and reactivity of hydroxyapatite without modifying its phase. Physical and chemical properties of the new derivative particles were analyzed. The biocompatibility of modified Nano-Hap on Raw 264.7 cells was also assessed.

  18. Nano-plasmonic antennas in the near infrared regime.

    PubMed

    Berkovitch, N; Ginzburg, P; Orenstein, M

    2012-02-22

    Plasmonic nano-antennas constitute a central research topic in current science and engineering with an enormous variety of potential applications. Here we review the recent progress in the niche of plasmonic nano-antennas operating in the near infrared part of the spectrum which is important for a variety of applications. Tuning of the resonance into the near infrared regime is emphasized in the perspectives of fabrication, measurement, modeling, and analytical treatments, concentrating on the vast recent achievements in these areas.

  19. Nano-ionomer tooth repair in pediatric dentistry.

    PubMed

    Killian, Constance Marie; Croll, Theodore P

    2010-01-01

    Resin-modified glass ionomer cements have shown their reliability and durability in various applications in young dental patients. The latest generation of these materials, the nano-ionomer, has been introduced, and its improved properties make it an effective alternative for restoring primary and permanent teeth. The purpose of this paper was to describe the properties of the nano-ionomer, provide indications for its use, and illustrate the technique for applying the material. Representative clinical cases are presented.

  20. Hydrodynamics of Macromolecular and Nano-Composite Materials

    DTIC Science & Technology

    2005-08-05

    polymer solutions or melts, biaxial liquid crystal polymers or suspension flows of biaxial nano-particles; (b). studies of nematodynamics as well as...performance material; (c). development of an effective theory to characterize the effective material properties for the nano- suspension and/or liquid crystal...polymer; (d). studies of coupled flow and magnetic and electric field assisted rocessing for liquid crystal polymers as well as suspension flows

  1. Relaxed structural property of Al nano-cluster: Theory

    NASA Astrophysics Data System (ADS)

    Diwan, Bhoopendra Dhar; Khaskalam, Amit

    2013-06-01

    In this paper we have studied the thermodynamic property of metallic Aluminium (Al) nano-clusters with relaxed structure by model approach. The relaxed cohesive energy is higher than that of the un-relaxed one due to relaxation process decreasing the total energy. It is found that cohesive energy of nano-clauster depends on the size of the clusters and increase with increasing the cluster size.

  2. The heterogeneity of spermatogonia is revealed by their topology and expression of marker proteins including the germ cell-specific proteins Nanos2 and Nanos3.

    PubMed

    Suzuki, Hitomi; Sada, Aiko; Yoshida, Shosei; Saga, Yumiko

    2009-12-15

    Spermatogonial stem cells (SSCs) reside in undifferentiated type-A spermatogonia and contribute to continuous spermatogenesis by maintaining the balance between self-renewal and differentiation, thereby meeting the biological demand in the testis. Spermatogonia have to date been characterized principally through their morphology, but we herein report the detailed characterization of undifferentiated spermatogonia in mouse testes based on their gene expression profiles in combination with topological features. The detection of the germ cell-specific proteins Nanos2 and Nanos3 as markers of spermatogonia has enabled the clear dissection of complex populations of these cells as Nanos2 was recently shown to be involved in the maintenance of stem cells. Nanos2 is found to be almost exclusively expressed in A(s) to A(pr) cells, whereas Nanos3 is detectable in most undifferentiated spermatogonia (A(s) to A(al)) and differentiating A(1) spermatogonia. In our present study, we find that A(s) and A(pr) can be basically classified into three categories: (1) GFRalpha1(+)Nanos2(+)Nanos3(-)Ngn3(-), (2) GFRalpha1(+)Nanos2(+)Nanos3(+)Ngn3(-), and (3) GFRalpha1(-)Nanos2(+/-)Nanos3(+)Ngn3(+). We propose that the first of these groups is most likely to include the stem cell population and that Nanos3 may function in transit amplifying cells.

  3. The many faces of nano in newspaper reporting

    NASA Astrophysics Data System (ADS)

    Boholm, Max; Boholm, Åsa

    2012-02-01

    The morpheme nano in languages such as Swedish and English is a constituent of many words. This article linguistically analyses the meaning potential of nano by focusing on word use in a Swedish newspaper corpus comprising 2,564 articles (1.6 million words) covering a 22-year period (1988-2010). Close to 400 word forms having nano as a constituent have been identified and analyzed. The results suggest that nano covers a broad and heterogeneous conceptual field: (i) as a prefix of the SI system; (ii) in relation to the scientific activities of nanoscience and nanotechnology, including their sub-processes and actors; and (iii) in relation to objects. The identified meanings of nano, besides the standard definition (i.e. `billionth part' in relation to SI units), are `operating at the nanometre level' in relation to activities and their actors and `nanometre sized' and `nanotechnological' in relation to objects; in addition, the less precise and non-technical meaning `very small' is identified. We discuss the implications of the findings for a hypothesis about media influence on public understanding of technology, suggesting that repeated findings in Europe and the USA of little self-reported understanding and knowledge of nanotechnology or nanoscience among the public make sense in light of the polysemy of nano reflected in its broad variety of verbal forms and usages.

  4. Second strain gradient elasticity of nano-objects

    NASA Astrophysics Data System (ADS)

    Cordero, Nicolas M.; Forest, Samuel; Busso, Esteban P.

    2016-12-01

    Mindlin's second strain gradient continuum theory for isotropic linear elastic materials is used to model two different kinds of size-dependent surface effects observed in the mechanical behaviour of nano-objects. First, the existence of an initial higher order stress represented by Mindlin's cohesion parameter, b0, makes it possible to account for the relaxation behaviour of traction-free surfaces. Second, the higher order elastic moduli, ci, coupling the strain tensor and its second gradient are shown to significantly affect the apparent elastic properties of nano-beams and nano-films under uni-axial loading. These two effects are independent from each other and allow for separated identification of the corresponding material parameters. Analytical results are provided for the size-dependent apparent shear modulus of a nano-thin strip under shear. Finite element simulations are then performed to derive the dependence of the apparent Young modulus and Poisson ratio of nano-films with respect to their thickness, and to illustrate hole free surface relaxation in a periodic nano-porous material.

  5. Application of Gaia Analysis Software AGIS to Nano-JASMINE

    NASA Astrophysics Data System (ADS)

    Yamada, Y.; Lammers, U.; Gouda, N.

    2011-07-01

    The core data reduction for the Nano-JASMINE mission is planned to be done with Gaia's Astrometric Global Iterative Solution (AGIS). Nano-JASMINE is an ultra small (35 kg) satellite for astrometry observations in Japan and Gaia is ESA's large (over 1000 kg) next-generation astrometry mission. The accuracy of Nano-JASMINE is about 3 mas, comparable to the Hipparcos mission, Gaia's predecessor some 20 years ago. It is challenging that such a small satellite can perform real scientific observations. The collaboration for sharing software started in 2007. In addition to similar design and operating principles of the two missions, this is possible thanks to the encapsulation of all Gaia-specific aspects of AGIS in a Parameter Database. Nano-JASMINE will be the test bench for the Gaia AGIS software. We present this idea in detail and the necessary practical steps to make AGIS work with Nano-JASMINE data. We also show the key mission parameters, goals, and status of the data reduction for the Nano-JASMINE.

  6. Synthesis and characterization of monosodium urate (MSU) nano particles

    NASA Astrophysics Data System (ADS)

    Tank, Nirali S.; Rathod, K. R.; Parekh, B. B.; Parikh, K. D.; Joshi, M. J.

    2016-05-01

    In Gout the deposition of crystals of Monosodium Urate (MSU) in various connective tissues and joints occurs, which is very painful with immflamation. The deposition likely to begin with nano particles form and expected to grow in to micro-paricles and hence it is important to synthesize and characrterize MSU nano-particles. The MSU nano particles were synthesized by wet chemical method using NaOH and uric acid (C5H4N4O3) and then characterized by powder XRD, TEM, FT-IR and thermal analysis. From the powder XRD the triclinic structure was found and 40 nm average particle size was estimated by using Scherrer's formula. From TEM the particle size was found to be in the range of 20 to 60 nm. The FT-IR spectrum for the MSU nano particles confirmed the presence of O-H stretching, N-H stretching, N-H rocking, C = O, C = C Enol or Keto and C = N vibrations. The thermal analysis was carried out from room temperature to 900°C. With comparison to the bulk MSU the thermal stability of MSU nano particles was slightly higher and 1.5 water molecules were found to be associated with MSU nano particles. Present results are compared with the bulk MSU.

  7. Modelling of nano-silica in cement paste

    NASA Astrophysics Data System (ADS)

    Rupasinghe, Madhuwanthi; Mendis, Priyan; Sofi, Massoud; Ngo, Tuan

    2013-08-01

    Recently published experimental evidence shows that nano-silica is a material that can be used to enhance the strength and durability characteristics of concrete. Engineered concrete at the nano-scale is achieved through the integration of nano-materials in suitable proportions and relevant mixing methods. Being a pozzolanic and reactive material along with nucleation effects and miniature particle size, nano-silica has been found to significantly improve the micro-structural characteristics of concrete making it denser and more uniform. The ongoing research work at the University of Melbourne is based on a novel modelling approach to further investigate the performance characteristics of nano-silica on cement paste at the micro-meter scale. The volumetric proportions of different phases present in concrete are computed considering hydration characteristics of cement and those of nanosilica. A Representative Volume Element (RVE) of the cement paste at micro scale is developed considering the hydrated gel as the matrix material while other phases present are integrated as randomly distributed spherical particles. Constitutive material models for these phases are assumed. The stress-strain relationship for the RVE is then generated using COMSOL Multiphysics software. The approach proposed in this paper is an initiation towards developing an acute and compressive model to predict the performance characteristics of nano-engineered concrete.

  8. Investigation of nanoSQUID designs for practical applications

    NASA Astrophysics Data System (ADS)

    Bechstein, Sylke; Köhn, Claudia; Drung, Dietmar; Storm, Jan-Hendrik; Kieler, Oliver; Morosh, Viacheslav; Schurig, Thomas

    2017-03-01

    In the recent past, considerable effort was spent on the development of superconducting quantum interference device (SQUID) designs for magnetic detection in the micro- and nano-scale. Where these novel nanoSQUIDs were mostly of a simple format, real applications require more elaborate designs including auxiliary components such as coils and transformers. Therefore, we have developed SQUID designs based on a Nb/HfTi/Nb thin-film technology which offers both, nano-patterning and waferscale manufacturing of complex design structures. Employing e-beam lithography and chemical–mechanical polishing process steps, the area of the superconductor–normal conductor–superconductor Josephson junctions of these nanoSQUIDs has been varied between 150 nm × 150 nm and 200 nm × 200 nm, whereas the thickness of the barrier is about 20 nm. In order to enable real practical applications, nanoSQUID designs with a number of implemented auxiliary components and design features, such as gradiometric feedback loops, gradiometric transformers, and rf filters, have been carefully investigated. This paper combines a summary of recent achievements with a presentation of detailed measurements of the device performance in magnetic fields of up to a few tens of millitesla. This investigation is intended to pave the way for future practical complex nanoSQUID tools.

  9. Nano forsterite biocomposites for medical applications: Mechanical properties and bioactivity.

    PubMed

    Furtos, Gabriel; Naghiu, Marieta-Adriana; Declercq, Heidi; Gorea, Maria; Prejmerean, Cristina; Pana, Ovidiu; Tomoaia-Cotisel, Maria

    2016-10-01

    The aim of the present study was to obtain and to investigate nano forsterite and nano forsterite biocomposites for biomedical application. New self-curing forsterite biocomposites were obtained by mixing nano forsterite powder (5, 15, 30, 50, 70 wt %) with 2,2-bis[4-(2-hydroxy-3-methacryloyloxypropoxy)-phenyl]propane (bis-GMA) and triethyleneglycol dimethacrylate (TEGDMA) monomers. The new nano forsterite biocomposites were investigated for mechanical properties: compressive strength (CS) (143-147.12 MPa), compressive modulus (CM) (1.67-2.75 GPa), diametral tensile strength (DTS) (27.33-31.55 MPa), flexural strength (FS) (59.47-83.20 MPa) and flexural modulus (FM) (2.05-8.60 GPa). Increases of CS, DTS, FS with increasing amount of forsterite were observed up to 50 wt %. The highest CM and FM values were registered for 70 wt % and a direct correlation between the forsterite volume fraction (%) was observed. SEM micrographs revealed the morphology of surface of fractured biocomposites after CS test. XPS indicated that these biocomposites promoted the hydroxyapatite formation on their surface immersed in simulated body fluid (SBF). AFM images showed that the growth of the hydroxyapatite layer occurs with a preferred orientation on the surface of forsterite biocomposites after immersion in SBF. Incorporation of nano forsterite in the polymer matrix (bis-GMA/TEGDMA) did show osteoblast adhesion and proliferation was improved on nano forsterite biocomposites. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 1290-1301, 2016.

  10. Control and Optimization of Coherence of a Nano-Sized Spin-Torque Microwave Oscillator for Military Nano-Electronics

    DTIC Science & Technology

    2008-12-01

    Recent discovery of the spin-torque effect (Slonczewski, 1996; Berger, 1996; Tsoi et al., 1998; Kiselev et al., 2003) in magnetic multilayers driven...which consists of a nano-scale metallic contact attached to a magnetic multilayer or a multilayered magnetic nano-pillar (Slavin and Tiberkevich...and is, in general, close to the ferromagnetic resonance ( FMR ) frequency 0ω of the “free” magnetic layer (upper blue layer in Fig.1). From the

  11. Mirror Metrology Using Nano-Probe Supports

    NASA Technical Reports Server (NTRS)

    Robinson, David; Hong, Maoling; Byron, Glenn; McClelland, Ryan; Chan, Kai-Wing

    2012-01-01

    Thin, lightweight mirrors are needed for future x-ray space telescopes in order to increase x-ray collecting area while maintaining a reduced mass and volume capable of being launched on existing rockets. However, it is very difficult to determine the undistorted shape of such thin mirrors because the mounting of the mirror during measurement causes distortion. Traditional kinematic mounts have insufficient supports to control the distortion to measurable levels and prevent the mirror from vibrating during measurement. Over-constrained mounts (non-kinematic) result in an unknown force state causing mirror distortion that cannot be determined or analytically removed. In order to measure flexible mirrors, it is necessary to over-constrain the mirror. Over-constraint causes unknown distortions to be applied to the mirror. Even if a kinematic constraint system can be used, necessary imperfections in the kinematic assumption can lead to an unknown force state capable of distorting the mirror. Previously, thicker, stiffer, and heavier mirrors were used to achieve low optical figure distortion. These mirrors could be measured to an acceptable level of precision using traditional kinematic mounts. As lighter weight precision optics have developed, systems such as the whiffle tree or hydraulic supports have been used to provide additional mounting supports while maintaining the kinematic assumption. The purpose of this invention is to over-constrain a mirror for optical measurement without causing unacceptable or unknown distortions. The invention uses force gauges capable of measuring 1/10,000 of a Newton attached to nano-actuators to support a thin x-ray optic with known and controlled forces to allow for figure measurement and knowledge of the undeformed mirror figure. The mirror is hung from strings such that it is minimally distorted and in a known force state. However, the hanging mirror cannot be measured because it is both swinging and vibrating. In order to

  12. Pressurized nano-liquid-junction interface for coupling capillary electrochromatography and nano-liquid chromatography with mass spectrometry.

    PubMed

    D'Orazio, Giovanni; Fanali, Salvatore

    2013-11-22

    A new nano-liquid-junction interface for coupling both capillary electrochromatography (CEC) or nano-liquid chromatography (nano-LC) with mass spectrometry (MS) was studied. The interface was a small T piece of polymeric material where capillary column and tip capillary were positioned at 180° while the third exit (at 90°) was occupied by a capillary delivering a liquid-assisting spray ionization for CEC experiments or by the electrode for the high voltage spray for nano-LC. Experiments were carried out analyzing mixtures of some organophosphorus pesticides (OPPs) or anti-inflammatory and related acidic drugs with MS detection in positive or negative ion mode, respectively. Analyzed OPPs compounds were baseline resolved utilizing the novel interface in both nano-LC and CEC obtaining good sensitivity and repeatability. For CEC-MS, the limits of detection ranged between 0.03 and 6.80 μg/mL and the intra-day repeatability was RSD <3.8% and <13% for the retention times and peak areas, respectively. The interface was easy to handle and good reproducibility, between 2.5 and 3.5% for the retention time and <10% for the efficiencies, was obtained when the interface was installed by two different analysts. Furthermore, it could be used for both CEC and nano-LC.

  13. The nano-epsilon dot method for strain rate viscoelastic characterisation of soft biomaterials by spherical nano-indentation.

    PubMed

    Mattei, G; Gruca, G; Rijnveld, N; Ahluwalia, A

    2015-10-01

    Nano-indentation is widely used for probing the micromechanical properties of materials. Based on the indentation of surfaces using probes with a well-defined geometry, the elastic and viscoelastic constants of materials can be determined by relating indenter geometry and measured load and displacement to parameters which represent stress and deformation. Here we describe a method to derive the viscoelastic properties of soft hydrated materials at the micro-scale using constant strain rates and stress-free initial conditions. Using a new self-consistent definition of indentation stress and strain and corresponding unique depth-independent expression for indentation strain rate, the epsilon dot method, which is suitable for bulk compression testing, is transformed to nano-indentation. We demonstrate how two materials can be tested with a displacement controlled commercial nano-indentor using the nano-espilon dot method (nano-ε̇M) to give values of instantaneous and equilibrium elastic moduli and time constants with high precision. As samples are tested in stress-free initial conditions, the nano-ε̇M could be useful for characterising the micro-mechanical behaviour of soft materials such as hydrogels and biological tissues at cell length scales.

  14. Where bone meets implant: the characterization of nano-osseointegration

    NASA Astrophysics Data System (ADS)

    Grandfield, Kathryn; Gustafsson, Stefan; Palmquist, Anders

    2013-05-01

    The recent application of electron tomography to the study of biomaterial interfaces with bone has brought about an awareness of nano-osseointegration and, to a further extent, demanded increasingly advanced characterization methodologies. In this study, nanoscale osseointegration has been studied via laser-modified titanium implants. The micro- and nano-structured implants were placed in the proximal tibia of New Zealand white rabbits for six months. High-resolution transmission electron microscopy (HRTEM), analytical microscopy, including energy dispersive X-ray spectroscopy (EDXS) and energy-filtered TEM (EFTEM), as well as electron tomography studies were used to investigate the degree of nano-osseointegration in two- and three-dimensions. HRTEM indicated the laser-modified surface encouraged the formation of crystalline hydroxyapatite in the immediate vicinity of the implant. Analytical studies suggested the presence of a functionally graded interface at the implant surface, characterized by the gradual intermixing of bone with oxide layer. Yet, the most compelling of techniques, which enabled straightforward visualization of nano-osseointegration, proved to be segmentation of electron tomographic reconstructions, where thresholding techniques identified bone penetrating into the nanoscale roughened surface features of laser-modified titanium. Combining high-resolution, analytical and three-dimensional electron microscopy techniques has proven to encourage identification and understanding of nano-osseointegration.The recent application of electron tomography to the study of biomaterial interfaces with bone has brought about an awareness of nano-osseointegration and, to a further extent, demanded increasingly advanced characterization methodologies. In this study, nanoscale osseointegration has been studied via laser-modified titanium implants. The micro- and nano-structured implants were placed in the proximal tibia of New Zealand white rabbits for six months

  15. Performance of concrete incorporating colloidal nano-silica

    NASA Astrophysics Data System (ADS)

    Zeidan, Mohamed Sabry

    Nanotechnology, as one of the most modern fields of science, has great market potential and economic impact. The need for research in the field of nanotechnology is continuously on the rise. During the last few decades, nanotechnology was developing rapidly into many fields of applied sciences, engineering and industrial applications, especially through studies of physics, chemistry, medicine and fundamental material science. These new developments may be attributed to the fact that material properties and performance can be significantly improved and controlled through nano-scale processes and nano-structures. This research program aims at 1) further understanding the behavior of cementitious materials when amended on the nano-scale level and 2) exploring the effect of this enhancement on the microstructure of cement matrix. This study may be considered as an important step towards better understanding the use of nano-silica in concrete. The main goal of the study is to investigate the effect of using colloidal nano-silica on properties of concrete, including mechanical properties, durability, transport properties, and microstructure. The experimental program that was conducted included a laboratory investigation of concrete mixtures in which nano-silica was added to cement or to a combination of cement and Class F fly ash. Various ratios of nano-silica were used in concrete mixtures to examine the extent and types of improvements that could be imparted to concrete. The conducted experimental program assessed these improvements in terms of reactivity, mechanical properties, and durability of the mixtures under investigation. Advanced testing techniques---including mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM)---were used to investigate the effect of nano-silica on the microstructure of the tested mixtures. In addition, the effect of nano-silica on the alkali-silica reaction (ASR) was examined using various techniques, including testing

  16. Comparison of Antimicrobial Properties of Nano Quinolone with its Microscale Effects

    NASA Astrophysics Data System (ADS)

    Behbahani, G. Rezaie; Sadr, M. Hossaini; Nabipour, H.; Behbahani, H. Rezaei; Vahedpour, M.; Barzegar, L.

    2013-06-01

    Nano nalidixic acid was prepared by ultrasonic method in carbon tetrachloride. Nano nalidixic acid (quinolone antibiotic) was characterized by X-ray diffraction (XRD), infrared spectroscopy (IR) and scanning electron microscope (SEM). The antibacterial activities of nano nalidixic acid were tested against microorganisms and compared with the microscale drug. The results show that nano nalidixic acid has good inhibitory properties against two Gram-positive species, Staphylococcus aureus and Bacillus subtilis. Nano nalidixic acid also showed good antifungal activity against Candida albicans. Nano nalidixic acid can be injected into the human body as a decontaminating agent to prevent the growth of harmful microorganisms more effectively than the micro-sized drug.

  17. Formation of surface nano-structures by plasma expansion induced by highly charged ions

    SciTech Connect

    Moslem, W. M.; El-Said, A. S.

    2012-12-15

    Slow highly charged ions (HCIs) create surface nano-structures (nano-hillocks) on the quartz surface. The formation of hillocks was only possible by surpassing a potential energy threshold. By using the plasma expansion approach with suitable hydrodynamic equations, the creation mechanism of the nano-hillocks induced by HCIs is explained. Numerical analysis reveal that within the nanoscale created plasma region, the increase of the temperature causes an increase of the self-similar solution validity domain, and consequently the surface nano-hillocks become taller. Furthermore, the presence of the negative (positive) nano-dust particles would lead to increase (decrease) the nano-hillocks height.

  18. Framing the nano-biointeractions by proteomics

    NASA Astrophysics Data System (ADS)

    Sabella, S.; Maiorano, G.; Rizzello, L.; Kote, S.; Cingolani, R.; Pompa, P. P.

    2012-03-01

    Knowledge of the molecular mechanisms underlying the interactions between nanomaterials and living systems is fundamental for providing more effective products for nanomedicine and drug delivery. Controlling the response of cells/bacteria (such as activation of inflammatory processes or apoptosis/necrosis in tumor cells or pathogenic bacteria) by tuning specific properties of the nanomaterials is ultimately the challenging goal. Notably, this may also provide crucial information in the assessment of any toxic risks induced by nanoparticles on humans. However, in studying the nano-biointeractions, it is imperative to take into account the dynamic evolutions of nanoparticles in the biological environments (in terms of protein corona formation, size and charge changes) in synergy with the dynamic events occurring in cells, including signal transduction, metabolic processes, homeostasis and membrane trafficking. In this context, we discuss the impact of analytical technologies, especially in the field of proteomics, which can provide major insights into the processes affecting the NPs surface as well as the cells and bacteria functionalities. In particular, we show that a precise control of the chemical-physical characteristics of the interacting nanoparticles or nanostructures may impact the cells by inducing changes in the proteomic profiles with direct consequences on their viability.

  19. Nano-encapsulated PCM via Pickering Emulsification

    PubMed Central

    Wang, Xuezhen; Zhang, Lecheng; Yu, Yi-Hsien; Jia, Lisi; Sam Mannan, M.; Chen, Ying; Cheng, Zhengdong

    2015-01-01

    We designed a two-step Pickering emulsification procedure to create nano-encapsulated phase changing materials (NEPCMs) using a method whose simplicity and low energy consumption suggest promise for scale-up and mass production. Surface-modified amphiphilic zirconium phosphate (ZrP) platelets were fabricated as the Pickering emulsifiers, nonadecane was chosen as the core phase change material (PCM), and polystyrene, the shell material. The resultant capsules were submicron in size with remarkable uniformity in size distribution, which has rarely been reported. Differential scanning calorimetry (DSC) characterization showed that the capsulation efficiency of NEPCMs, and they were found to be thermal stable, as characterized by the DSC data for the sample after 200 thermal cycles. NEPCMs exhibit superior mechanical stability and mobility when compared with the well-developed micro-encapsulated phase change materials (MEPCMs). NEPCMs find useful applications in thermal management, including micro-channel coolants; solar energy storage media; building temperature regulators; and thermal transfer fabrics. PMID:26278332

  20. Nano-porous calcium phosphate balls.

    PubMed

    Kovach, Ildyko; Kosmella, Sabine; Prietzel, Claudia; Bagdahn, Christian; Koetz, Joachim

    2015-08-01

    By dropping a NaH2PO4·H2O precursor solution to a CaCl2 solution at 90°C under continuous stirring in presence of two biopolymers, i.e. gelatin (G) and chitosan (C), supramolecular calcium phosphate (CP) card house structures are formed. Light microscopic investigations in combination with scanning electron microscopy show that the GC-based flower-like structure is constructed from very thin CP platelets. Titration experiments indicate that H-bonding between both biopolymers is responsible for the synergistic effect in presence of both polymers. Gelatin-chitosan-water complexes play an important role with regard to supramolecular ordering. FTIR spectra in combination with powder X-ray diffraction show that after burning off all organic components (heating up >600°C) dicalcium and tricalcium phosphate crystallites are formed. From high resolution transmission electron microscopy (HR-TEM) it is obvious to conclude, that individual crystal platelets are dicalcium phosphates, which build up ball-like supramolecular structures. The results reveal that the GC guided crystal growth leads to nano-porous supramolecular structures, potentially attractive candidates for bone repair.

  1. Lipids, curvature, and nano-medicine*

    PubMed Central

    Mouritsen, Ole G

    2011-01-01

    The physical properties of the lamellar lipid-bilayer component of biological membranes are controlled by a host of thermodynamic forces leading to overall tensionless bilayers with a conspicuous lateral pressure profile and build-in curvature-stress instabilities that may be released locally or globally in terms of morphological changes. In particular, the average molecular shape and the propensity of the different lipid and protein species for forming non-lamellar and curved structures are a source of structural transitions and control of biological function. The effects of different lipids, sterols, and proteins on membrane structure are discussed and it is shown how one can take advantage of the curvature-stress modulations brought about by specific molecular agents, such as fatty acids, lysolipids, and other amphiphilic solutes, to construct intelligent drug-delivery systems that function by enzymatic triggering via curvature. Practical applications: The simple concept of lipid molecular shape and how it impacts on the structure of lipid aggregates, in particular the curvature and curvature stress in lipid bilayers and liposomes, can be exploited to construct liposome-based drug-delivery systems, e.g., for use as nano-medicine in cancer therapy. Non-lamellar-forming lysolipids and fatty acids, some of which may be designed to be prodrugs, can be created by phospholipase action in diseased tissues thereby providing for targeted drug release and proliferation of molecular entities with conical shape that break down the permeability barrier of the target cells and may hence enhance efficacy. PMID:22164124

  2. Nano Robotic Manipulation inside Electron Microscopes

    NASA Astrophysics Data System (ADS)

    Fukuda, Toshio; Nakajima, Masahiro; Liu, Pou

    We report nanomanipulation and nanoassembly through nanorobotic manipulation inside electron microscopes. A hybrid nanorobotic manipulation system, which is integrated with a nanorobotic manipulator inside a transmission electron microscope (TEM) and nanorobotic manipulators inside a scanning electron microscope (SEM), is used. The elasticity of a multi-walled CNT (MWNT) is measured inside a TEM. The telescoping MWNT is fabricated by peeling off outer layers through destructive fabrication process. The electrostatic actuation of telescoping MWNT is directly observed by a TEM. A cutting technique for CNTs assisted by the presence of oxygen gas is also presented. The cutting procedure was conducted in less than 1 minute using a low-energy electron beam inside a scanning electron microscope. A bending technique of a CNT assisted by the presence of oxygen gas is also applied for the 3-D fabrication of nanosturucture. We expect that these techniques will be applied for the rapid prototyping nanoassembly of various CNT nanodevices. For the nano-biological applications, environmental-SEM (E-SEM) nanomanipulation system is also presented with the direct observation of the hydroscopic samples with non-drying treatment.

  3. Micro and nano patternable magnetic carbon

    NASA Astrophysics Data System (ADS)

    Sharma, Swati; Rostas, Arpad M.; Bordonali, Lorenzo; MacKinnon, Neil; Weber, Stefan; Korvink, Jan G.

    2016-12-01

    Carbon is conventionally not associated with magnetism, causing much of the discussion of its perspectives in nanotechnology to be centred on its electron-transport properties. Among the few existing examples of magnetic carbon production, none has found a direct route into scalable micro- and nanofabrication. Here we introduce a magnetic form of carbon whose precursor polymers can be lithographically patterned into micro- and nano-structures prior to pyrolysis. This unreactive and thermally robust material features a strong, room-temperature magnetism owing to a large number of unpaired electron spins with restricted mobility, which is achieved by controlling the progression of bond dissociation and formation during pyrolysis. The micro-manufacture of pyrolytic magnetic carbon, having (3.5 ±0.7 )×1015 spins/mg, can immediately benefit a number of spintronic and magnetic-microelectromechanical system applications, and the fabrication of composite magnetic materials. The material could also complement the magnetic resonance spectroscopy and imaging techniques. Additionally, this contribution sheds light on the controversial theories concerning the existence and mechanism of magnetic phenomena in carbon.

  4. Inflammatory response to nano- and microstructured hydroxyapatite.

    PubMed

    Mestres, Gemma; Espanol, Montserrat; Xia, Wei; Persson, Cecilia; Ginebra, Maria-Pau; Ott, Marjam Karlsson

    2015-01-01

    The proliferation and activation of leukocytes upon contact with a biomaterial play a crucial role in the degree of inflammatory response, which may then determine the clinical failure or success of an implanted biomaterial. The aim of this study was to evaluate whether nano- and microstructured biomimetic hydroxyapatite substrates can influence the growth and activation of macrophage-like cells. Hydroxyapatite substrates with different crystal morphologies consisting of an entangled network of plate-like and needle-like crystals were evaluated. Macrophage proliferation was evaluated on the material surface (direct contact) and also in extracts i.e. media modified by the material (indirect contact). Additionally, the effect of supplementing the extracts with calcium ions and/or proteins was investigated. Macrophage activation on the substrates was evaluated by quantifying the release of reactive oxygen species and by morphological observations. The results showed that differences in the substrate's microstructure play a major role in the activation of macrophages as there was a higher release of reactive oxygen species after culturing the macrophages on plate-like crystals substrates compared to the almost non-existent release on needle-like substrates. However, the difference in macrophage proliferation was ascribed to different ionic exchanges and protein adsorption/retention from the substrates rather than to the texture of materials.

  5. Spin nano-oscillator-based wireless communication.

    PubMed

    Choi, Hyun Seok; Kang, Sun Yool; Cho, Seong Jun; Oh, Inn-Yeal; Shin, Mincheol; Park, Hyuncheol; Jang, Chaun; Min, Byoung-Chul; Kim, Sang-Il; Park, Seung-Young; Park, Chul Soon

    2014-06-30

    Spin-torque nano-oscillators (STNOs) have outstanding advantages of a high degree of compactness, high-frequency tunability, and good compatibility with the standard complementary metal-oxide-semiconductor process, which offer prospects for future wireless communication. There have as yet been no reports on wireless communication using STNOs, since the STNOs also have notable disadvantages such as lower output power and poorer spectral purity in comparison with those of LC voltage-controlled oscillators. Here we show that wireless communication is achieved by a proper choice of modulation scheme despite these drawbacks of STNOs. By adopting direct binary amplitude shift keying modulation and non-coherent demodulation, we demonstrate STNO-based wireless communication with 200-kbps data rate at a distance of 1 m between transmitter and receiver. It is shown, from the analysis of STNO noise, that the maximum data rate can be extended up to 1.48 Gbps with 1-ns turn-on time. For the fabricated STNO, the maximum data rate is 5 Mbps which is limited by the rise time measured in the total system. The result will provide a viable route to real microwave application of STNOs.

  6. Nano-enabled SERS reporting photosensitizers.

    PubMed

    Farhadi, Arash; Roxin, Áron; Wilson, Brian C; Zheng, Gang

    2015-01-01

    To impart effective cellular damage via photodynamic therapy (PDT), it is vital to deliver the appropriate light dose and photosensitizer concentration, and to monitor the PDT dose delivered at the site of interest. In vivo monitoring of photosensitizers has in large part relied on their fluorescence emission. Palladium-containing photosensitizers have shown promising clinical results by demonstrating near full conversion of light to PDT activity at the cost of having undetectable fluorescence. We demonstrate that, through the coupling of plasmonic nanoparticles with palladium-photosensitizers, surface-enhanced Raman scattering (SERS) provides both reporting and monitoring capability to otherwise quiescent molecules. Nano-enabled SERS reporting of photosensitizers allows for the decoupling of the therapeutic and imaging mechanisms so that both phenomena can be optimized independently. Most importantly, the design enables the use of the same laser wavelength to stimulate both the PDT and imaging features, opening the potential for real-time dosimetry of photosensitizer concentration and PDT dose delivery by SERS monitoring.

  7. Polymer hybrid nano/micro composites

    SciTech Connect

    Dzenis, Y.A.; Reneker, D.H.

    1994-12-31

    Nanocomposites based on ceramic and metal matrices attracted considerable attention during the past decade. Polymer based nanocomposites are much less well-known. Recently, a method of electrospinning of thin polymer fibers has been developed. Continuous, oriented fibers with diameters ranging from 50 nanometers to several microns have been prepared from over 30 different synthetic and natural polymers, including high temperature high modulus polyimide and polyaramid (Kevlar) fibers. The possible applications of these small fibers in hybrid polymer hierarchical composites are discussed. Micromechanics models of hybrid composites are developed based on the models for two component composites and on the principle of effective homogeneity. Effective thermoviscoelastic characteristics of nano and microfiber composite as well as nanofiber and microparticulate composites are calculated. ``Strong`` hybrid effects are observed in the dependence of effective moduli, loss factor, creep factor, and thermal expansion coefficient on fractional content of fibers of different diameters. The extrema are located at the higher fractions of larger reinforcing elements. Similarities of composite microstructures having synergistic ``extremal`` properties with some biological composites are noted.

  8. Nano-functionalization of protein microspheres

    NASA Astrophysics Data System (ADS)

    Yoon, Sungkwon; Nichols, William T.

    2014-08-01

    Protein microspheres are promising building blocks for the assembly of complex functional materials. Here we demonstrate a set of three techniques that add functionality to the surface of protein microspheres. In the first technique, a positive surface charge on the protein spheres is deposited by electrostatic adsorption. Negatively charged silica and gold nanoparticle colloids can then electrostatically bind reversibly to the microsphere surface. In the second technique, nanoparticles are covalently anchored to the protein shell using a simple one-pot process. The strong covalent bond between sulfur groups in cysteine in the protein shell irreversibly binds to the gold nanoparticles. In the third technique, surface morphology of the protein microsphere is tuned through hydrodynamic instability at the water-oil interface. This is accomplished through the degree of solubility of the oil phase in water. Taken together these three techniques form a platform to create nano-functionalized protein microspheres, which can then be used as building blocks for the assembly of more complex macroscopic materials.

  9. Nano-scaled chalcogenide-based memories.

    PubMed

    Redaelli, Andrea; Pirovano, Agostino

    2011-06-24

    Today phase change memory (PCM) technology has reached product maturity at 90 and 65 nm nodes, while the 45 nm node is under development and is expected to enter in the market soon. The continuous decrease of the cell size with scaling leads to an effective active area as small as 150 nm(2) and an active volume involved in the phase transformation of about 10(4) nm(3), thus entering definitively into the nanotechnology world. At this extremely reduced dimension, the reliability of the device must be carefully investigated. In this work we show that the cycling performance of the device is well maintained, not being a problem for either the bipolar transistor or the storage element. The phase transition from the amorphous to the crystalline state is, of course, one of the most interesting phenomena, impacting cell retention capability and device performance. The stochastic nature of nano-nuclei percolation in the amorphous matrix is shown as an important ingredient in the retention of PCM devices. The related dispersion in crystallization times is analyzed through a crystallization Monte Carlo model and a physical insight into nucleation and growth mechanisms is provided.

  10. Next generation nano-contamination monitoring

    NASA Astrophysics Data System (ADS)

    Kochevar, Steven; Pietrykowski, Thomas; Rodier, Dan

    2012-10-01

    Current particle counting techniques employ common technologies: lasers, detectors, and optics. The theory of light scattering and particles is well known, and is standard in most particle counters. However, the need to detect smaller particles (nanoparticles) challenges the technological limits of traditional light-scattering techniques. Counting nanoparticles in liquids offers unique problems because of the intensity of scattered light from the particles relative to the light scattered by the fluid and flow cell. Consequently, the particle may be lost in the background noise. New technologies employ sophisticated detection elements and high-powered lasers to provide three-dimensional particle signatures and real-time videos as the particle passes through the laser. Aerosol nanoparticle counting offers the challenge of light scatter in an open sample chamber. Simply, the nanoparticles are too small to be effectively illuminated by lasers, so a new technique employs dynamic mobility to classify specific particle sizes. This technique can provide particle counting - and accurate particle size classification - down to 5 nm. Employing traditional optical particle counting technology is not efficient for detecting nanoparticles, but new technologies can meet these challenges. When combined with other support equipment (e.g. WiFi, software, etc.), new technologies provide innovative techniques for monitoring nanoparticles and managing nano-contamination in clean environments.

  11. Nano-Aramid Fiber Reinforced Polyurethane Foam

    NASA Technical Reports Server (NTRS)

    Semmes, Edmund B.; Frances, Arnold

    2008-01-01

    Closed cell polyurethane and, particularly, polyisocyanurate foams are a large family of flexible and rigid products the result of a reactive two part process wherein a urethane based polyol is combined with a foaming or "blowing" agent to create a cellular solid at room temperature. The ratio of reactive components, the constituency of the base materials, temperature, humidity, molding, pouring, spraying and many other processing techniques vary greatly. However, there is no known process for incorporating reinforcing fibers small enough to be integrally dispersed within the cell walls resulting in superior final products. The key differentiating aspect from the current state of art resides in the many processing technologies to be fully developed from the novel concept of milled nano pulp aramid fibers and their enabling entanglement capability fully enclosed within the cell walls of these closed cell urethane foams. The authors present the results of research and development of reinforced foam processing, equipment development, strength characteristics and the evolution of its many applications.

  12. NanoComposite Stainless Steel Powder Technologies

    SciTech Connect

    DeHoff, R.; Glasgow, C.

    2012-07-25

    Oak Ridge National Laboratory has been investigating a new class of Fe-based amorphous material stemming from a DARPA, Defense Advanced Research Projects Agency initiative in structural amorphous metals. Further engineering of the original SAM materials such as chemistry modifications and manufacturing processes, has led to the development of a class of Fe based amorphous materials that upon processing, devitrify into a nearly homogeneous distribution of nano sized complex metal carbides and borides. The powder material is produced through the gas atomization process and subsequently utilized by several methods; laser fusing as a coating to existing components or bulk consolidated into new components through various powder metallurgy techniques (vacuum hot pressing, Dynaforge, and hot isostatic pressing). The unique fine scale distribution of microstructural features yields a material with high hardness and wear resistance compared to material produced through conventional processing techniques such as casting while maintaining adequate fracture toughness. Several compositions have been examined including those specifically designed for high hardness and wear resistance and a composition specifically tailored to devitrify into an austenitic matrix (similar to a stainless steel) which poses improved corrosion behavior.

  13. The eNanoMapper database for nanomaterial safety information

    PubMed Central

    Chomenidis, Charalampos; Doganis, Philip; Fadeel, Bengt; Grafström, Roland; Hardy, Barry; Hastings, Janna; Hegi, Markus; Jeliazkov, Vedrin; Kochev, Nikolay; Kohonen, Pekka; Munteanu, Cristian R; Sarimveis, Haralambos; Smeets, Bart; Sopasakis, Pantelis; Tsiliki, Georgia; Vorgrimmler, David; Willighagen, Egon

    2015-01-01

    Summary Background: The NanoSafety Cluster, a cluster of projects funded by the European Commision, identified the need for a computational infrastructure for toxicological data management of engineered nanomaterials (ENMs). Ontologies, open standards, and interoperable designs were envisioned to empower a harmonized approach to European research in nanotechnology. This setting provides a number of opportunities and challenges in the representation of nanomaterials data and the integration of ENM information originating from diverse systems. Within this cluster, eNanoMapper works towards supporting the collaborative safety assessment for ENMs by creating a modular and extensible infrastructure for data sharing, data analysis, and building computational toxicology models for ENMs. Results: The eNanoMapper database solution builds on the previous experience of the consortium partners in supporting diverse data through flexible data storage, open source components and web services. We have recently described the design of the eNanoMapper prototype database along with a summary of challenges in the representation of ENM data and an extensive review of existing nano-related data models, databases, and nanomaterials-related entries in chemical and toxicogenomic databases. This paper continues with a focus on the database functionality exposed through its application programming interface (API), and its use in visualisation and modelling. Considering the preferred community practice of using spreadsheet templates, we developed a configurable spreadsheet parser facilitating user friendly data preparation and data upload. We further present a web application able to retrieve the experimental data via the API and analyze it with multiple data preprocessing and machine learning algorithms. Conclusion: We demonstrate how the eNanoMapper database is used to import and publish online ENM and assay data from several data sources, how the “representational state transfer

  14. Shape-tailored porous gold nanowires: from nano barbells to nano step-cones.

    PubMed

    Laocharoensuk, Rawiwan; Sattayasamitsathit, Sirilak; Burdick, Jared; Kanatharana, Proespichaya; Thavarungkul, Panote; Wang, Joseph

    2007-12-01

    Step-like porous gold nanowires of different shapes and diameters have been prepared by sequentially depositing alloy segments composed of different gold/silver ratios and de-alloying the silver component. For example, step-cone and nano-barbell porous gold nanowires were generated by a membrane-templated sequential deposition of gold-silver alloy segments from plating solutions of respectively decreasing or alternating gold/silver composition ratios. Alloy segments of different gold/silver ratios, prepared by using different plating potentials, also lead to multistep nanowires. In addition to step-like nanowires, we describe the preparation of cone- and bone-shaped porous nanowires from alloy nanowires of longitudinally changing compositions, generated via deposition from a flowing plating solution of a continuously changing composition. Such customization of the porous gold nanostructure is attributed to the chemical removal of silver and the different extents of gold reordering from alloy segments of different compositions. The latter leads to porous gold segments of smaller diameters from silver-rich alloy segments. The new "nanomachining" concept is versatile and could be extended to nanowires of diverse shapes with a variety of properties, generating an attractive assortment of nano-hardware.

  15. Modeling the Charge Transport in Graphene Nano Ribbon Interfaces for Nano Scale Electronic Devices

    NASA Astrophysics Data System (ADS)

    Kumar, Ravinder; Engles, Derick

    2015-05-01

    In this research work we have modeled, simulated and compared the electronic charge transport for Metal-Semiconductor-Metal interfaces of Graphene Nano Ribbons (GNR) with different geometries using First-Principle calculations and Non-Equilibrium Green's Function (NEGF) method. We modeled junctions of Armchair GNR strip sandwiched between two Zigzag strips with (Z-A-Z) and Zigzag GNR strip sandwiched between two Armchair strips with (A-Z-A) using semi-empirical Extended Huckle Theory (EHT) within the framework of Non-Equilibrium Green Function (NEGF). I-V characteristics of the interfaces were visualized for various transport parameters. The distinct changes in conductance and I-V curves reported as the Width across layers, Channel length (Central part) was varied at different bias voltages from -1V to 1 V with steps of 0.25 V. From the simulated results we observed that the conductance through A-Z-A graphene junction is in the range of 10-13 Siemens whereas the conductance through Z-A-Z graphene junction is in the range of 10-5 Siemens. These suggested conductance controlled mechanisms for the charge transport in the graphene interfaces with different geometries is important for the design of graphene based nano scale electronic devices like Graphene FETs, Sensors.

  16. Characterization of nano-scaled metal-hydrides confined in nano-porous carbon frameworks

    NASA Astrophysics Data System (ADS)

    Peaslee, David Edward

    Metal hydrides are currently being studied to provide hydrogen for use in fuel cells and for transportation applications. Hydrogen can be stored in chemical compounds at higher density and lower volume than liquid H2 or compressed gas. Thermodynamic properties of metal hydrides differ between bulk and nano-sized particles. Many metal hydrides with useful volumetric and gravimetric capacities have high decomposition temperatures, but when placed in nano-sized frameworks (or templates) desorption and adsorption temperatures can be fine-tuned to meet engineering requirements for real-world systems. Additionally, some metal hydrides have shown a change in the decomposition pathway when infiltrated into these frameworks, thereby reducing the amount of unwanted byproducts, and potentially improving the cyclability of the material. The Temperature Programmed Decomposition Mass Spectrum Residual Gas Analyzer can be used to characterize gas desorption, decomposition temperatures, picogram changes in mass, and ionization energies for a variety of materials and gasses. The goal of the system is to characterize desorption of the hydrogen (including byproduct gasses) and the decomposition of the metal hydrides. The experimental apparatus is composed of four main components: the residual gas analyzer (RGA), the low temperature stage quartz crystal microbalance (QCM), the high temperature heating stage, and two vacuum chambers separated by a small flow hole which allows a direct line-of-site to the RGA.

  17. Infrared nano-imaging and nano-spectroscopy of surface plasmons in bilayer graphene

    NASA Astrophysics Data System (ADS)

    Fei, Zhe; Iwinski, Eric G.; Rodin, Alesandr S.; Wagner, Martin; Liu, Mengkun; Dai, Siyuan; Goldflam, Michael D.; Bao, Wenzhong; Lee, Yongjin; Lau, Chun Ning; Kailmann, Fritz; Castro-Neto, Antonio H.; Zhang, Lingfeng M.; Fogler, Michael M.; Basov, Dimitri N.

    2014-03-01

    Bernal stacking bilayer graphene (BLG) has demonstrated its capability for application in a wide range of fields including electronics, photonics and energy engineering. So far, plasmonic properties of BLG have not been fully explored experimentally despite broad interests. Here, we report infrared nano-imaging and nano-spectroscopy of surface plasmons (SPs) in BLG. We found that BLG also supported gate-tunable SPs in the mid-infrared range with nevertheless smaller wavelength compared to equally doped single-layer graphene (SLG) and randomly stacked double-layer graphene (DLG). In addition, the coupling between BLG plasmons and SiO2 phonons appeared much weaker compared to SLG plasmons. Further analysis indicated that these observations about SPs in BLG were attributed to interlayer coupling that affects strongly the electronic structure. Our work uncovered all the essential characteristics of BLG plasmons, and suggested the possibility of developing carbon-based plasmonic circuits where SLG, BLG and DLG are all functioning building blocks.

  18. Synthesis and photoluminescence enhancement of nano-PAA-ZnCl2 with controllable dimension and morphology

    NASA Astrophysics Data System (ADS)

    Wu, Jianguo; Wang, Kaige; Zhou, Yukun; Wang, Shuang; Zhang, Chen; Wang, Guiren; Bai, Jintao

    2016-12-01

    One kind of ZnCl2 nano-films with controllable dimension and morphology is successfully synthesized on the top surface of nano-porous anodic alumina membrane (nano-PAAM) by self-organized method. The nano-PAA-ZnCl2 composite films are characterized by field emission scanning electron microscopy, energy dispersive spectrometer, and laser confocal Raman spectroscopy. The results indicate that the concentration of initial ZnCl2 solution, the depth of nano-PAAM substrate and the growth time of ZnCl2 crystals have important influences on the properties of nano-composite films. Furthermore, the characteristics of nano-composites such as the photoluminescence (PL) spectra are investigated. Compared with the nano-PAAM substrate, at room temperature, all of the nano-PAA-ZnCl2 composite films have both the same excitation center (335 nm) and emission center (430 nm), no matter what the nano-composite morphologies being; and the PL intensity of nano-PAA-ZnCl2 composite films are all enhanced and the maximum enhancement is two times; after annealing at 500 °C, the emission spectra of the nano-composite films stabilized at the 385 nm, 402 nm and 430 nm. The research provides a new, simple, economical and practical technology to fabricate nano-PAA composite films with higher luminousintensity.

  19. Synthesis and implementation of nano-chitosan and its acetophenone derivative for enhanced removal of metals.

    PubMed

    Mahmoud, Mohamed E; Abou Kana, Maram T H; Hendy, Ahmed A

    2015-11-01

    In the present study, nano-chitosan (Nano-Ch) was synthesized by ionic gelation of chitosan/tripolyphosphate system and successfully modified with acetophenone via Schiff's base condensation to produce nano-chitosan-modified-actophenone (Nano-Ch-Ac). The produced nano-materials were characterized by FT-IR, SEM, HR-TEM and TGA techniques. The average particle sizes were found in the range of 5.20-14.54nm based on the HR-TEM analysis. The metal interaction properties of Nano-Ch and Nano-Ch-Ac with Cu(II), Cd(II), Hg(II) and Pb(II) were compared in presence of various experimental parameters. Nano-Ch-Ac sorbent was found more superior in the extraction processes of all examined metal ions under the evaluated experimental parameters. This trend was confirmed from the highest determined metal sorption capacity values of metal ions as 1298-1608 and 810-1236μmolg(-1) in pH 7.0 by Nano-Ch-Ac and Nano-Ch sorbents, respectively. The adsorption equilibrium was established at 30.0min of contact time by the two nano-chitosan sorbents. The superiority of Nano-Ch-Ac was also confirmed from the dynamic applications of this nano-sorbent for removal of divalent metal ions from tap water, sea water and industrial wastewater (91.3-100.0±1.0-3.0).

  20. Enhancement of light harvesting efficiency of silicon solar cell utilizing arrays of poly(methyl methacrylate-co-acrylic acid) nano-spheres and nano-spheres with embedded silver nano-particles

    NASA Astrophysics Data System (ADS)

    Lee, Chee-Leong; Goh, Wee-Sheng; Chee, Swee-Yong; Yik, Lai-Kuan

    2017-02-01

    An array of uniformly distributed monolayer of poly(methyl methacrylate-co-acrylic acid) nano-spheres were deposited onto an amorphous silicon photovoltaic cell utilizing dip coating technique. The electrical characteristics of the coated photovoltaic cell reveal that the nano-spheres with an average diameter size of 101 nm exhibits excellent light harvesting characteristics if compared to the nano-spheres of other sizes. The power conversion efficiency from such integration of the nano-structures (i.e. 3.14% per PV cell) indicates that at least 1.6 times of improvement (or relative enhancement of 57%) can be achieved comparatively to the uncoated photovoltaic cell (i.e. 2% per PV cell). Further increment of the power conversion efficiency of the solar cell has been attained with the incorporation of the silver nano-particles into the nano-spheres of similar average size. With the inclusion of the silver nano-particles into such nano-spheres, the power conversion efficiency of the solar cell has attained 5.57% per PV cell, which is about 2.8 times (or relative enhancement of 179%) if compared to the uncoated samples. Hence, this novel and controllable technique of fabricating omnidirectional light-harvesting nano-spheres with embedded silver nano-particles will indubitably be beneficial to various types of optoelectronic devices.

  1. Modeling and control for micro and nano manipulation

    NASA Astrophysics Data System (ADS)

    Wejinya, Uchechukwu C.

    Manipulation of micro and nano entities implies the movement of micro and nano entities from an initial position (location) to the desire position (location). This operation is not only necessary, but a required task with great precision. The tools needed for the manipulation needs to be chosen properly because the capabilities of the human hand are very restricted. Smart micro and nano manipulation are becoming of great interest in many applications including medicine and industry. In industry, high precision manipulation systems are especially needed for mass production of both micro and nano systems which consist of different component in respective scales. The transition from assembling and manipulating micro and nano entities manually to mass products with high quality is only attainable by automated assembly and manipulation systems. An example is the testing of integrated circuits which can be carried out by exchanging the manipulation tool by an electric probe. Furthermore, in medical research it is customary to pick up a single cell (human, plant, or animal), and carry it to another device which is used to further analyze the cell. Consequently, the cell of interest has to be separated from the other cells and picked up using the appropriate micro/nano tool. Hence it becomes absolutely necessary that the appropriate tool be used for specific micro or nano entity manipulation and assembly. In this research, we focus on developing micro tool for manipulating micro and nano entities in liquid environment using a micro fluidic end effector system with in-situ Polyvinylidene Fluoride (PVDF) sensing. The microfluidic end effector system consists of a DC micro-diaphragm pump and compressor, one region of flexible latex tube, a Polyvinylidene Fluoride (PVDF) sensor for in-situ measurement of micro drag force, and a micro pipette. The micro pipette of the novel microfluidic end effector system has an internal diameter (ID) smaller than 20mum used for microfluidic

  2. NanoClusters Enhance Drug Delivery in Mechanical Ventilation

    NASA Astrophysics Data System (ADS)

    Pornputtapitak, Warangkana

    The overall goal of this thesis was to develop a dry powder delivery system for patients on mechanical ventilation. The studies were divided into two parts: the formulation development and the device design. The pulmonary system is an attractive route for drug delivery since the lungs have a large accessible surface area for treatment or drug absorption. For ventilated patients, inhaled drugs have to successfully navigate ventilator tubing and an endotracheal tube. Agglomerates of drug nanoparticles (also known as 'NanoClusters') are fine dry powder aerosols that were hypothesized to enable drug delivery through ventilator circuits. This Thesis systematically investigated formulations of NanoClusters and their aerosol performance in a conventional inhaler and a device designed for use during mechanical ventilation. These engineered powders of budesonide (NC-Bud) were delivered via a MonodoseRTM inhaler or a novel device through commercial endotracheal tubes, and analyzed by cascade impaction. NC-Bud had a higher efficiency of aerosol delivery compared to micronized stock budesonide. The delivery efficiency was independent of ventilator parameters such as inspiration patterns, inspiration volumes, and inspiration flow rates. A novel device designed to fit directly to the ventilator and endotracheal tubing connections and the MonodoseRTM inhaler showed the same efficiency of drug delivery. The new device combined with NanoCluster formulation technology, therefore, allowed convenient and efficient drug delivery through endotracheal tubes. Furthermore, itraconazole (ITZ), a triazole antifungal agent, was formulated as a NanoCluster powder via milling (top-down process) or precipitation (bottom-up process) without using any excipients. ITZ NanoClusters prepared by wet milling showed better aerosol performance compared to micronized stock ITZ and ITZ NanoClusters prepared by precipitation. ITZ NanoClusters prepared by precipitation methods also showed an amorphous state

  3. Nano-LISA for in vitro diagnostic applications

    NASA Astrophysics Data System (ADS)

    Maswadi, Saher; Glickman, Randolph D.; Elliott, Rowe; Barsalou, Norman

    2011-03-01

    We previously reported the detection of bacterial antigen with immunoaffinity reactions using laser optoacoustic spectroscopy and antibody-coupled gold nanorods (Ab-NR) as a contrast agent specifically targeted to the antigen of interest. The Nano-LISA (Nanoparticle Linked Immunosorbent Assay) method has been adapted to detect three very common blood-borne viral infectious agents, i.e. human T-lymphotropic virus (HTLV), human immunodeficiency virus (HIV) and hepatitis-B (Hep-B). These agents were used in a model test panel to illustrate the performance of the Nano-LISA technique. A working laboratory prototype of a Nano-LISA microplate reader-sensor was assembled and tested against the panel containing specific antigens of each of the infectious viral agents. Optoacoustic (OA) responses generated by the samples were detected using the probe beam deflection technique, an all-optical, non-contact technique. A LabView graphical user interface was developed for control of the instrument and real-time display of the test results. The detection limit of Nano-LISA is at least 1 ng/ml of viral antigen, and can reach 10 pg/ml, depending on the binding affinity of the specific detection antibody used to synthesize the Ab-NR. The method has sufficient specificity, i.e. the detection reagents do not cross-react with noncomplementary antigens. Thus, the OA microplate reader, incorporating NanoLISA, has adequate detection sensitivity and specificity for use in clinical in vitro diagnostic testing.

  4. NanoSail - D Orbital and Attitude Dynamics

    NASA Technical Reports Server (NTRS)

    Heaton, Andrew F.; Faller, Brent F.; Katan, Chelsea K.

    2013-01-01

    NanoSail-D unfurled January 20th, 2011 and successfully demonstrated the deployment and deorbit capability of a solar sail in low Earth orbit. The orbit was strongly perturbed by solar radiation pressure, aerodynamic drag, and oblate gravity which were modeled using STK HPOP. A comparison of the ballistic coefficient history to the orbit parameters exhibits a strong relationship between orbital lighting, the decay rate of the mean semi-major axis and mean eccentricity. A similar comparison of mean solar area using the STK HPOP solar radiation pressure model exhibits a strong correlation of solar radiation pressure to mean eccentricity and mean argument of perigee. NanoSail-D was not actively controlled and had no capability on-board for attitude or orbit determination. To estimate attitude dynamics we created a 3-DOF attitude dynamics simulation that incorporated highly realistic estimates of perturbing forces into NanoSail-D torque models. By comparing the results of this simulation to the orbital behavior and ground observations of NanoSail-D, we conclude that there is a coupling between the orbit and attitude dynamics as well as establish approximate limits on the location of the NanoSail-D solar center of pressure. Both of these observations contribute valuable data for future solar sail designs and missions.

  5. He bubble growth and interaction in W nano-tendrils

    NASA Astrophysics Data System (ADS)

    Smirnov, R. D.; Krasheninnikov, S. I.

    2015-11-01

    Tungsten plasma-facing components (PFCs) in fusion devices are exposed to variety of extreme plasma conditions, which can lead to alteration of tungsten micro-structure and degradation of the PFCs. In particular, it is known that filamentary nano-structures called fuzz can grow on helium plasma exposed tungsten surfaces. However, mechanism of the fuzz growth is still not fully understood. Existing experimental observations indicate that formation of helium nano-bubbles in tungsten plays essential role in fuzz formation and growth. In this work we investigate mechanisms of growth and interaction of helium bubbles in fuzz-like nano-tendrils using molecular dynamics simulations with LAMMPS code. We show that growth of the bubbles has anisotropic character producing complex stress field in the nano-tendrils with distinct compression and tension regions. We found that formation of large inter-bubble tension regions can cause lateral stretching and bending of the tendrils that consequently lead to their elongation and thinning at the stretching sites. The rate of nano-tendril growth due to the described mechanism is also evaluated from the simulations.

  6. Polychromatic white LED using GaN nano pyramid structure

    NASA Astrophysics Data System (ADS)

    Kim, Taek; Kim, Jusung; Yang, Moonseung; Park, Yongsoo; Chung, U.-In; Ko, Yongho; Cho, Yonghoon

    2013-03-01

    We have developed monolithic white light emitting diodes (LEDs) with a hybrid structure of planar c-planes and nano size hexagonal pyramids. The white spectrum is composed of blue and yellow emissions from the InGaN multi quantum wells (MQWs) on the planar c-planes and on the nano pyramids, respectively. The yellow emission is originated from quantum wells, wires, and dots that are formed at the sides, edges, and tops of the nano-pyramids, respectively. As a result, the emission peaks are different and the entire yellow spectrum is broad enough to make a white in combination with a blue emission. The longer wavelength from the InGaN on nano-pyramids than the wavelength from the InGaN on c-planes is explained by excess In supply from the dielectric selective growth mask. The color temperature is tuned from 3600K to 6400K by controlling the relative area ratio of c-plane and nano-pyramids.

  7. Nano zinc oxide-sodium alginate antibacterial cellulose fibres.

    PubMed

    Varaprasad, Kokkarachedu; Raghavendra, Gownolla Malegowd; Jayaramudu, Tippabattini; Seo, Jongchul

    2016-01-01

    In the present study, antibacterial cellulose fibres were successfully fabricated by a simple and cost-effective procedure by utilizing nano zinc oxide. The possible nano zinc oxide was successfully synthesized by precipitation technique and then impregnated effectively over cellulose fibres through sodium alginate matrix. XRD analysis revealed the 'rod-like' shape alignment of zinc oxide with an interplanar d-spacing of 0.246nm corresponding to the (101) planes of the hexagonal wurtzite structure. TEM analysis confirmed the nano dimension of the synthesized zinc oxide nanoparticles. The presence of nano zinc oxide over cellulose fibres was evident from the SEM-EDS experiments. FTIR and TGA studies exhibited their effective bonding interaction. The tensile stress-strain curves data indicated the feasibility of the fabricated fibres for longer duration utility without any significant damage or breakage. The antibacterial studies against Escherichia coli revealed the excellent bacterial devastation property. Further, it was observed that when all the parameters remained constant, the variation of sodium alginate concentration showed impact in devastating the E. coli. In overall, the fabricated nano zinc oxide-sodium alginate cellulose fibres can be effectively utilized as antibacterial fibres for biomedical applications.

  8. Ecological assessment of nano-enabled supercapacitors for automotive applications

    NASA Astrophysics Data System (ADS)

    Weil, M.; Dura, H.; Shimon, B.; Baumann, M.; Zimmermann, B.; Ziemann, S.; Lei, C.; Markoulidis, F.; Lekakou, T.; Decker, M.

    2012-09-01

    New materials on nano scale have the potential to overcome existing technical barriers and are one of the most promising key technologies to enable the decoupling of economic growth and resource consumption. Developing these innovative materials for industrial applications means facing a complex quality profile, which includes among others technical, economic, and ecological aspects. So far the two latter aspects are not sufficiently included in technology development, especially from a life cycle point of view. Supercapacitors are considered a promising option for electric energy storage in hybrid and full electric cars. In comparison with presently used lithium based electro chemical storage systems supercapacitors possess a high specific power, but a relatively low specific energy. Therefore, the goal of ongoing research is to develop a new generation of supercapacitors with high specific power and high specific energy. To reach this goal particularly nano materials are developed and tested on cell level. In the presented study the ecological implications (regarding known environmental effects) of carbon based nano materials are analysed using Life Cycle Assessment (LCA). Major attention is paid to efficiency gains of nano particle production due to scaling up of such processes from laboratory to industrial production scales. Furthermore, a developed approach will be displayed, how to assess the environmental impact of nano materials on an automotive system level over the whole life cycle.

  9. Growth mechanism of carbon nanotubes: a nano Czochralski model

    PubMed Central

    2012-01-01

    Carbon nanotubes (CNTs) have been under intense investigations during the past two decades due to their unique physical and chemical properties; however, there is still no commonly accepted growth mechanism to describe the growth behavior of CNTs. Here, we propose a nano Czochralski (CZ) model which regards the catalytic growth of a CNT as a CZ process taking place on the nano scale. The main idea is that, during the CNT growth, each catalyst particle acts as a nano crucible to nucleate and maintain the CNT growth, and the extruding CNT rotates relative to the nano crucible, leading to a chirality-dependent growth rate. In this case, the structural quality gradually changes along the CNT due to the dynamic generation-reconstruction-diffusion of defects during the CNT growth. The nano CZ mechanism may also apply to the catalytic growth of many other one-dimensional (1D) nanostructures (including various nanotubes and nanowires), thus further efforts will be stimulated in the quality and property control, as well as application explorations of these 1D nanomaterials. PMID:22747835

  10. NanoSQUIDs based on niobium nitride films

    NASA Astrophysics Data System (ADS)

    Russo, R.; Esposito, E.; Crescitelli, A.; Di Gennaro, E.; Granata, C.; Vettoliere, A.; Cristiano, R.; Lisitskiy, M.

    2017-02-01

    We present an experimental investigation of nanoSQUIDs based on niobium nitride films. Niobium nitride has a relatively high critical temperature and a large upper critical magnetic field, making it a good material for superconducting electronics working in high magnetic field. We have fabricated nanoSQUIDs using electron beam lithography lift-off technique and deposition of niobium nitride films by magnetron sputtering at room temperature. The characterization of nanoSQUIDs was performed at 4.2 K and it consists mainly of current-voltage (IV) characteristics and critical current as a function of external magnetic field (magnetic pattern). The fabricated nanoSQUIDs show a hysteretic IV characteristic and they present a multi-values magnetic pattern. We show that by reducing the critical current by ion etching it is possible to obtain nanoSQUIDs with a single value magnetic pattern suitable for magnetic particle measurements. Magnetic noise analysis has been performed and a white noise of 0.3 μΦ0 Hz-1/2 has been estimated.

  11. PREFACE: International Conference on Structural Nano Composites (NANOSTRUC 2012)

    NASA Astrophysics Data System (ADS)

    Njuguna, James

    2012-09-01

    Dear Colleagues It is a great pleasure to welcome you to NanoStruc2012 at Cranfield University. The purpose of the 2012 International Conference on Structural Nano Composites (NanoStruc2012) is to promote activities in various areas of materials and structures by providing a forum for exchange of ideas, presentation of technical achievements and discussion of future directions. NanoStruc brings together an international community of experts to discuss the state-of-the-art, new research results, perspectives of future developments, and innovative applications relevant to structural materials, engineering structures, nanocomposites, modelling and simulations, and their related application areas. The conference is split in 7 panel sessions, Metallic Nanocomposites and Coatings, Silica based Nanocomposites, safty of Nanomaterials, Carboin based Nanocomposites, Multscale Modelling, Bio materials and Application of Nanomaterials. All accepted Papers will be published in the IOP Conference Series: Materials Science and Engineering (MSE), and included in the NanoStruc online digital library. The abstracts will be indexed in Scopus, Compedex, Inspec, INIS (International Nuclear Information System), Chemical Abstracts, NASA Astrophysics Data System and Polymer Library. Before ending this message, I would like to acknowledge the hard work, professional skills and efficiency of the team which ensured the general organisation. As a conclusion, I would like to Welcome you to the Nanostruc2012 and wish you a stimulating Conference and a wonderful time. On behalf of the scientific committee, Signature James Njuguna Conference Chair The PDF of this preface also contains committee listings and associates logos.

  12. Leaching of nano-ZnO in municipal solid waste.

    PubMed

    Sakallioglu, T; Bakirdoven, M; Temizel, I; Demirel, B; Copty, N K; Onay, T T; Uyguner Demirel, C S; Karanfil, T

    2016-11-05

    Despite widespread use of engineered nanomaterials (ENMs) in commercial products and their potential disposal in landfills, the fate of ENMs in solid waste environments are still not well understood. In this study, the leaching behavior of nano ZnO -one of the most used ENMs- in fresh municipal solid waste (MSW) was investigated. Batch reactors containing municipal solid waste samples were spiked with three different types of nano ZnO having different surface stabilization. The leaching of ZnO was examined under acidic, basic and elevated ionic strength (IS) conditions. The results of the 3-day batch tests showed that the percent of the added nano-ZnO mass retained within the solid waste matrix ranged between 80% and 93% on average for the three types of nano-ZnO tested. The pH and IS conditions did not significantly influence the leaching behavior of ZnO. To further analyze the behavior of ZnO in the MSW matrix, a kinetic particle deposition/detachment model was developed. The model was able to reproduce the main trends of the batch experiments. Reaction rate constants for the batch tests ranged from 0.01 to 0.4 1/hr, reflecting the rapid deposition of nano-ZnO within the MSW matrix.

  13. Sprayable superhydrophobic nano-chains coating with continuous self-jumping of dew and melting frost

    PubMed Central

    Wang, Shanlin; Zhang, Wenwen; Yu, Xinquan; Liang, Caihua; Zhang, Youfa

    2017-01-01

    Spontaneous movement of condensed matter provides a new insight to efficiently improve condensation heat transfer on superhydrophobic surface. However, very few reports have shown the jumping behaviors on the sprayable superhydrophobic coatings. Here, we developed a sprayable silica nano-porous coating assembled by fluorinated nano-chains to survey the condensates’ dynamics. The dewdrops were continuously removed by self- and/or trigger-propelling motion due to abundant nano-pores from random multilayer stacking of nano-chains. In comparison, the dewdrops just could be slipped under the gravity effect on lack of nano-pores coatings stacked by silica nano-spheres and nano-aggregates. More interestingly, the spontaneous jumping effect also occurred on micro-scale frost crystals under the defrosting process on nano-chains coating surfaces. Different from self-jumping of dewdrops motion, the propelling force of frost crystals were provided by a sudden increase of the pressure under the frost crystal. PMID:28074938

  14. Sprayable superhydrophobic nano-chains coating with continuous self-jumping of dew and melting frost

    NASA Astrophysics Data System (ADS)

    Wang, Shanlin; Zhang, Wenwen; Yu, Xinquan; Liang, Caihua; Zhang, Youfa

    2017-01-01

    Spontaneous movement of condensed matter provides a new insight to efficiently improve condensation heat transfer on superhydrophobic surface. However, very few reports have shown the jumping behaviors on the sprayable superhydrophobic coatings. Here, we developed a sprayable silica nano-porous coating assembled by fluorinated nano-chains to survey the condensates’ dynamics. The dewdrops were continuously removed by self- and/or trigger-propelling motion due to abundant nano-pores from random multilayer stacking of nano-chains. In comparison, the dewdrops just could be slipped under the gravity effect on lack of nano-pores coatings stacked by silica nano-spheres and nano-aggregates. More interestingly, the spontaneous jumping effect also occurred on micro-scale frost crystals under the defrosting process on nano-chains coating surfaces. Different from self-jumping of dewdrops motion, the propelling force of frost crystals were provided by a sudden increase of the pressure under the frost crystal.

  15. Sprayable superhydrophobic nano-chains coating with continuous self-jumping of dew and melting frost.

    PubMed

    Wang, Shanlin; Zhang, Wenwen; Yu, Xinquan; Liang, Caihua; Zhang, Youfa

    2017-01-11

    Spontaneous movement of condensed matter provides a new insight to efficiently improve condensation heat transfer on superhydrophobic surface. However, very few reports have shown the jumping behaviors on the sprayable superhydrophobic coatings. Here, we developed a sprayable silica nano-porous coating assembled by fluorinated nano-chains to survey the condensates' dynamics. The dewdrops were continuously removed by self- and/or trigger-propelling motion due to abundant nano-pores from random multilayer stacking of nano-chains. In comparison, the dewdrops just could be slipped under the gravity effect on lack of nano-pores coatings stacked by silica nano-spheres and nano-aggregates. More interestingly, the spontaneous jumping effect also occurred on micro-scale frost crystals under the defrosting process on nano-chains coating surfaces. Different from self-jumping of dewdrops motion, the propelling force of frost crystals were provided by a sudden increase of the pressure under the frost crystal.

  16. Viscoelasticity of Epoxy nano-composites

    NASA Astrophysics Data System (ADS)

    Ahuja, Suresh

    2013-03-01

    Nanocomposites have been modeled in a multiscale covering from molecular scale (e.g., molecular dynamics, Monte Carlo), microscale (e.g., Brownian dynamics, dissipative particle dynamics, lattice Boltzmann, time-dependent Ginzburg-Landau method, dynamic density functional theory method) to mesoscale and macroscale (e.g., micromechanics, equivalent-continuum and self-similar approaches, finite element method) The presence of layered silicates in nonaqueous polymers changes the viscoelastic behavior of the unfilled matrix from liquid-like to solid-like because of the formation of a three-dimensional percolating network of exfoliated or intercalated stacks. This gel-like behavior is a direct consequence of the highly anisotropic nature of the nanoclays which prevents their free rotation and the dissipation of stress. Particle to particle interactions is the dominant mechanism in fumed silica nanocomposites whereas particle to polymer interaction is the dominant one in colloidal silica nanocomposites at identical filler concentrations. These interactions are balanced in each nanocomposite systems by the silica surface treatments (chain grafting, silane modification) and the molecular weight of the matrix. Two different types of nanocomposite structures exist namely, intercalated nanocomposites where the polymer chains are sandwiched between silicate layers and exfoliated nanocomposites where the layers can be considered individually but remain more or less dispersed in the polymer matrix. Yield stress from Carreau-Yasuda model has been correlated to exfoliation. Also, equilibrium modulus and zero shear rate viscosity has been used to analyze percolation threshold and sol-gel transition. Nano clays organically functionalized were mixed with Epoxy in a high shear mixer.

  17. Nano-ADEPT Aeroloads Wind Tunnel Test

    NASA Technical Reports Server (NTRS)

    Smith, Brandon; Yount, Bryan; Kruger, Carl; Brivkalns, Chad; Makino, Alberto; Cassell, Alan; Zarchi, Kerry; McDaniel, Ryan; Ross, James; Wercinski, Paul; Venkatapathy, Ethiraj; Swanson, Gregory; Gold, Nili

    2016-01-01

    A wind tunnel test of the Adaptable Deployable Entry and Placement Technology (ADEPT) was conducted in April 2015 at the US Army's 7 by10 Foot Wind Tunnel located at NASA Ames Research Center. Key geometric features of the fabric test article were a 0.7 meter deployed base diameter, a 70 degree half-angle forebody cone angle, eight ribs, and a nose-to-base radius ratio of 0.7. The primary objective of this wind tunnel test was to obtain static deflected shape and pressure distributions while varying pretension at dynamic pressures and angles of attack relevant to entry conditions at Earth, Mars, and Venus. Other objectives included obtaining aerodynamic force and moment data and determining the presence and magnitude of any dynamic aeroelastic behavior (buzz/flutter) in the fabric trailing edge. All instrumentation systems worked as planned and a rich data set was obtained. This paper describes the test articles, instrumentation systems, data products, and test results. Four notable conclusions are drawn. First, test data support adopting a pre-tension lower bound of 10 foot pounds per inch for Nano-ADEPT mission applications in order to minimize the impact of static deflection. Second, test results indicate that the fabric conditioning process needs to be reevaluated. Third, no flutter/buzz of the fabric was observed for any test condition and should also not occur at hypersonic speeds. Fourth, translating one of the gores caused ADEPT to generate lift without the need for a center of gravity offset. At hypersonic speeds, the lift generated by actuating ADEPT gores could be used for vehicle control.

  18. Nano-FTIR for Geochemical Sample Analysis

    NASA Astrophysics Data System (ADS)

    Dominguez, G.; McCleod, A.; Gainsforth, Z.; Keilmann, F.; Westphal, A.; Thiemens, M. H.; Basov, D.

    2014-12-01

    Infrared (IR) spectroscopy is considered by many to be the "gold standard" for chemical identification, providing a direct connection between chemical compounds found in the laboratory and those found in natural samples including remote astrophysical environments. However, a well known limitation of using conventional IR spectroscopy is its spatial resolution determined by the wavelength of IR photons. Thus, while other techniques such as XANES and micro-Raman are capable of limited functional group mapping at tens to hundreds of nanometers, their use is limited by accessibility (the need for synchrotron beamlines) or the need for intense irradiation conditions (Raman) that can lead to sample alteration. These limitations and the wealth of information that can be extracted from detailed studies of unique micron-sized samples brought back by recent sample return missions such as NASA's Stardust mission, have motivated the development of a novel infrared mapping technique that is capable of mapping the chemical functional properties of geochemical samples with submicron resolutions. Here we describe our nano-FTIR imaging and analysis technique that allows us to bypass diffraction limited sample imaging in the infrared. Here we show, for the first time, that 1) the combination of an atomic-force microscope (AFM) and laser can be used to obtain the FTIR-equivalent spectra on spatial scales that are much smaller than the wavelength of IR radiation used 2) this technique responds to subtle shifts in cation concentrations as evidenced by changes in the frequencies of phonons at sub-micron scales 3) this technique can be used to identify regions of crystalline and semi-crystalline materials as demonstrated in our analysis of a cometary dust grain Iris. This work has clear implications for interpretations of astronomical observations and adds a new technique for the non-destructive characterization of terrestrial and extraterrestrial samples.

  19. Improvement of Delamination Resistance in Composite Laminates with Nano-Interlayers (Preprint)

    DTIC Science & Technology

    2006-01-01

    AFRL-ML-WP-TP-2006-409 IMPROVEMENT OF DELAMINATION RESISTANCE IN COMPOSITE LAMINATES WITH NANO - INTERLAYERS (PREPRINT) Sangwook Sihn, Jin W...IMPROVEMENT OF DELAMINATION RESISTANCE IN COMPOSITE LAMINATES WITH NANO -INTERLAYERS (PREPRINT) 5c. PROGRAM ELEMENT NUMBER 62102F 5d. PROJECT NUMBER...is a nano -interlayer which can be fabricated in the form of either a thin film of nano -modified epoxy reinforced with vapor grown nanofibers or a

  20. Reverse micelle-loaded lipid nano-emulsions: new technology for nano-encapsulation of hydrophilic materials.

    PubMed

    Anton, Nicolas; Mojzisova, Halina; Porcher, Emilien; Benoit, Jean-Pierre; Saulnier, Patrick

    2010-10-15

    This study presents novel, recently patented technology for encapsulating hydrophilic species in lipid nano-emulsions. The method is based on the phase-inversion temperature method (the so-called PIT method), which follows a low-energy and solvent-free process. The nano-emulsions formed are stable for months, and exhibit droplet sizes ranging from 10 to 200 nm. Hydrophilic model molecules of fluorescein sodium salt are encapsulated in the oily core of these nano-emulsion droplets through their solubilisation in the reverse micellar system. As a result, original, multi-scaled nano-objects are generated with a 'hydrophilic molecule in a reverse-micelles-in-oil-in-water' structure. Once fluorescein has been encapsulated it remains stable, for thermodynamic reasons, and the encapsulation yields can reach 90%. The reason why such complex objects can be formed is due to the soft method used (PIT method) which allows the conservation of the structure of the reverse micelles throughout the formulation process, up to their entrapment in the nano-emulsion droplets. In this study, we focus the investigation on the process itself, revealing its potential and limits. Since the formulation of nanocarriers for the encapsulation of hydrophilic substances still remains a challenge, this study may constitute a significant advance in this field.

  1. Structural and optical characterization of GaAs nano-crystals selectively grown on Si nano-tips by MOVPE

    NASA Astrophysics Data System (ADS)

    Skibitzki, Oliver; Prieto, Ivan; Kozak, Roksolana; Capellini, Giovanni; Zaumseil, Peter; Arroyo Rojas Dasilva, Yadira; Rossell, Marta D.; Erni, Rolf; von Känel, Hans; Schroeder, Thomas

    2017-03-01

    We present the nanoheteroepitaxial growth of gallium arsenide (GaAs) on nano-patterned silicon (Si) (001) substrates fabricated using a CMOS technology compatible process. The selective growth of GaAs nano-crystals (NCs) was achieved at 570 °C by MOVPE. A detailed structure and defect characterization study of the grown nano-heterostructures was performed using scanning transmission electron microscopy, x-ray diffraction, micro-Raman, and micro-photoluminescence (μ-PL) spectroscopy. The results show single-crystalline, nearly relaxed GaAs NCs on top of slightly, by the SiO2-mask compressively strained Si nano-tips (NTs). Given the limited contact area, GaAs/Si nanostructures benefit from limited intermixing in contrast to planar GaAs films on Si. Even though a few growth defects (e.g. stacking faults, micro/nano-twins, etc) especially located at the GaAs/Si interface region were detected, the nanoheterostructures show intensive light emission, as investigated by μ-PL spectroscopy. Achieving well-ordered high quality GaAs NCs on Si NTs may provide opportunities for superior electronic, photonic, or photovoltaic device performances integrated on the silicon technology platform.

  2. Structural and optical characterization of GaAs nano-crystals selectively grown on Si nano-tips by MOVPE.

    PubMed

    Skibitzki, Oliver; Prieto, Ivan; Kozak, Roksolana; Capellini, Giovanni; Zaumseil, Peter; Arroyo Rojas Dasilva, Yadira; Rossell, Marta D; Erni, Rolf; von Känel, Hans; Schroeder, Thomas

    2017-03-01

    We present the nanoheteroepitaxial growth of gallium arsenide (GaAs) on nano-patterned silicon (Si) (001) substrates fabricated using a CMOS technology compatible process. The selective growth of GaAs nano-crystals (NCs) was achieved at 570 °C by MOVPE. A detailed structure and defect characterization study of the grown nano-heterostructures was performed using scanning transmission electron microscopy, x-ray diffraction, micro-Raman, and micro-photoluminescence (μ-PL) spectroscopy. The results show single-crystalline, nearly relaxed GaAs NCs on top of slightly, by the SiO2-mask compressively strained Si nano-tips (NTs). Given the limited contact area, GaAs/Si nanostructures benefit from limited intermixing in contrast to planar GaAs films on Si. Even though a few growth defects (e.g. stacking faults, micro/nano-twins, etc) especially located at the GaAs/Si interface region were detected, the nanoheterostructures show intensive light emission, as investigated by μ-PL spectroscopy. Achieving well-ordered high quality GaAs NCs on Si NTs may provide opportunities for superior electronic, photonic, or photovoltaic device performances integrated on the silicon technology platform.

  3. A dual-chambered microbial fuel cell with Ti/nano-TiO2/Pd nano-structure cathode

    NASA Astrophysics Data System (ADS)

    Hosseini, Mir Ghasem; Ahadzadeh, Iraj

    2012-12-01

    In this research, Ti/nano-TiO2/Pd nano-structure electrode is prepared, characterized and applied as cathode electrode in a dual-chambered microbial fuel cell with graphite anode and Flemion cation exchange membrane. Prepared nano-structured electrode morphology and mixed-culture biofilm formed on the anode are studied by scanning electron microscopy (SEM). Cell performance is investigated by polarization, cyclic voltammetery (CV) and electrochemical impedance spectroscopy (EIS) methods. Results show that Ti/nano-TiO2/Pd electrode exhibits satisfactory long term performance as a cathode to reduce water dissolved oxygen. The maximum output power of the cell is about 200 mW m-2 normalized to the cathode surface area. Open circuit potential (OCP) of the cell is about 480 mV and value of the short circuit current is 0.21 mA cm-2 of the cathode geometric surface area. Thus this nano-structure cathode can produce comparable output power to that of platinum-based cathodes such as Pt-doped carbon paper; therefore due to the ease of preparation and low cost, this electrode can be applied as alternative to platinum-based cathodes in microbial fuel cells.

  4. Nano-composite of silk fibroin-chitosan/Nano ZrO2 for tissue engineering applications: fabrication and morphology.

    PubMed

    Teimouri, Abbas; Ebrahimi, Raheleh; Emadi, Rahmatollah; Beni, Batool Hashemi; Chermahini, Alireza Najafi

    2015-05-01

    A scaffold possessing certain desired features such as biodegradation, biocompatibility, and porous structure could serve as a template for tissue engineering. In the present study, silk fibroin (SF), chitosan (CS) and zirconia (Nano ZrO2) were all combined using the freeze drying technique to fabricate a bio-composite scaffold. The composite scaffold (SF/CS/Nano ZrO2) was characterized by SEM, XRD, TGA, BET and FT-IR studies. The scaffold was found to possess a porous nature with pore dimensions suitable for cell infiltration and colonization. The presence of zirconia in the SF/CS/Nano ZrO2 scaffold led to an increase in compressive strength and water uptake capacity while at the same time decreasing the porosity. Cytocompatibility of the SF/CS/Nano ZrO2 scaffold, assessed by MTT assay, revealed non-toxicity to the Human Gingival Fibroblast (HGF, NCBI: C-131). Thus, we suggest that SF/CS/Nano ZrO2 composite scaffold is a potential candidate to be used for tissue engineering.

  5. Nano-antidotes for drug overdose and poisoning.

    PubMed

    Forster, Vincent; Leroux, Jean-Christophe

    2015-06-03

    The number of intoxications from xenobiotics--natural or synthetic foreign chemicals, or substances given in higher doses than typically present in humans--has risen tremendously in the last decade, placing poisoning as the leading external cause of death in the United States. This epidemic has fostered the development of antidotal nanomedicines, which we call "nano-antidotes," capable of efficiently neutralizing offending compounds in situ. Although prototype nano-antidotes have shown efficacy in proof-of-concept studies, the gap to clinical translation can only be filled if issues such as the clinical relevance of intoxication models and the safety profile of nano-antidotes are properly addressed. As the unmet medical needs in resuscitative care call for better treatments, this Perspective critically reviews the recent progress in antidotal medicine and emerging nanotechnologies.

  6. Guiding Molecular Motors with Nano-Imprinted Structures

    NASA Astrophysics Data System (ADS)

    Bunk, Richard; Carlberg, Patrick; Månsson, Alf; Nicholls, Ian A.; Omling, Pär; Sundberg, Mark; Tågerud, Sven; Montelius, Lars

    2005-05-01

    This work, for the first time, demonstrates that nano-imprinted samples, with 100 nm wide polymer lines, can act as guides for molecular motors consisting of motor proteins actin and myosin. The motor protein function was characterized using fluorescence microscopy and compared to actomyosin motility on non-structured nitrocellulose surfaces. Our results open for further use of the nano-imprint technique in the production of disposable chips for bio-nanotechnological applications and miniaturized biological test systems. We discuss how the nano-imprinted motor protein assay system may be optimized and also how it compares to previously tested assay systems involving low-resolution UV-lithography and low throughput but high-resolution electron beam lithography.

  7. Thermal performance of heat pipe with suspended nano-particles

    NASA Astrophysics Data System (ADS)

    Shukla, K. N.; Solomon, A. Brusly; Pillai, B. C.; Ruba Singh, B. Jacob; Saravana Kumar, S.

    2012-11-01

    Nanofluids are employed as the working medium for a conventional cylindrical heat pipe. A cylindrical copper heat pipe of 19.5 mm outer diameter and 400 mm length was fabricated and tested with two different working fluids. The working fluids used in this study are DI-water and Nano-particles suspension (mixture of copper nano particle and DI-water). The overall heat transfer coefficient of the heat pipe was calculated based on the lumped thermal resistance network and compared with the heat transfer coefficient of base fluid filled heat pipe. There is a quantitative improvement in the heat transfer coefficient using nano-particles suspension as the working medium. A heat transfer correlation was also developed based on multiple regression least square method and the results were compared with that obtained by the experiment.

  8. Mesenchymal Stem Cells and Nano-Bioceramics for Bone Regeneration.

    PubMed

    Kankilic, Berna; Köse, Sevil; Korkusuz, Petek; Timuçin, Muharrem; Korkusuz, Feza

    Orthopedic disorders and trauma usually result in bone loss. Bone grafts are widely used to replace this tissue. Bone grafts excluding autografts unfortunately have disadvantages like evoking immune response, contamination and rejection. Autografts are of limited sources and optimum biomaterials that can replace bone have been searched for several decades. Bioceramics, which have the similar inorganic structure of natural bone, are widely used to regenerate bone or coat metallic implants. As people continuously look for a higher life quality, there are developments in technology almost everyday to meet their expectations. Nanotechnology is one of such technologies and it attracts everyone's attention in biomaterial science. Nano scale biomaterials have many advantages like larger surface area and higher biocompatibility and these properties make them more preferable than micro scale. Also, stem cells are used for bone regeneration besides nano-bioceramics due to their differentiation characteristics. This review covers current research on nano-bioceramics and mesenchymal stem cells and their role in bone regeneration.

  9. A 20 nm spin Hall nano-oscillator.

    PubMed

    Dürrenfeld, Philipp; Awad, Ahmad A; Houshang, Afshin; Dumas, Randy K; Åkerman, Johan

    2017-01-19

    Spin Hall nano-oscillators (SHNOs) are an emerging class of pure spin current driven microwave signal generators. Through the fabrication of 20 nm nano-constrictions in Pt/NiFe bilayers, we demonstrate that SHNOs can be scaled down to truly nanoscopic dimensions, with the added benefit of ultra-low operating currents and improved power conversion efficiency. The lateral confinement leads to a strong shape anisotropy field as well as an additional demagnetizing field whose reduction with increasing auto-oscillation amplitude can yield a positive current tunability contrary to the negative tunability commonly observed for localized excitations in extended magnetic layers. Micromagnetic simulations corroborate the experimental findings and suggest that the active magnetodynamic area resides up to 100 nm outside of the nano-constriction.

  10. Formation of micro/nano structures out of soap bubbles

    NASA Astrophysics Data System (ADS)

    Bai, Xiao-Dan; Liu, Jing

    2007-07-01

    We proposed to synthesize, etch and construct micro/nano structures through manipulating the large-scale bubbles composed of specific chemical compounds. The core of the method lies in the chemical reaction occurred at the interfaces between two or more soap bubbles. A unique virtue of the bubble is that it can have a rather large diameter however an extremely small membrane thickness, whose smallest size could reach nano scale. Therefore, the chemical reaction and synthesis occurred in the common interface of such contacting bubbles would lead to products with very small size. Several typical micro structures were fabricated to demonstrate the feasibility of the new method. Being flexible, easily controllable and environment friendly, the present concept may open a straightforward low-cost way for making micro/nano structures.

  11. A triple quantum dot based nano-electromechanical memory device

    SciTech Connect

    Pozner, R.; Lifshitz, E.; Peskin, U.

    2015-09-14

    Colloidal quantum dots (CQDs) are free-standing nano-structures with chemically tunable electronic properties. This tunability offers intriguing possibilities for nano-electromechanical devices. In this work, we consider a nano-electromechanical nonvolatile memory (NVM) device incorporating a triple quantum dot (TQD) cluster. The device operation is based on a bias induced motion of a floating quantum dot (FQD) located between two bound quantum dots (BQDs). The mechanical motion is used for switching between two stable states, “ON” and “OFF” states, where ligand-mediated effective interdot forces between the BQDs and the FQD serve to hold the FQD in each stable position under zero bias. Considering realistic microscopic parameters, our quantum-classical theoretical treatment of the TQD reveals the characteristics of the NVM.

  12. Preparation and acute toxicology of nano-magnetic ferrofluid.

    PubMed

    Xia, Zefeng; Wang, Guobin; Tao, Kaixiong; Li, Jianxing; Tian, Yuan

    2005-01-01

    The nano-magnetic ferrofluid was prepared by chemical coprecipitation and its acute toxicology was investigated. The effective diameter (Eff. Diam. ) of the magnetic particles was about 19.9 nm, and the concentration of the ferrofluid was 17. 54 mg/ml. The acute toxic reaction and the main viscera pathological morphology of mice were evaluated after oral, intravenous and intraperitoneal administration of the nano-magnetic ferrofluid of different doses respectively. Half lethal dose (LD50) > 2104. 8 mg/kg,maximum non-effect dose (ED0) = 320. 10mg/kg with oral; LDs,> 438. 50 mg/kg, EDo = 160. 05 mg/kg with intravenous route; and LDso >1578. 6 mg/kg, ED0 = 320. 10 mg/kg with intraperitoneal administration. Degeneration and necrosis of viscera were not found. So the nano-magnetic ferrofluid, of which toxicity is very low, may be used as a drug carrier.

  13. About Nano-JASMINE Satellite System and Project Status

    NASA Astrophysics Data System (ADS)

    Sako, Nobutada

    Intelligent Space Systems Laboratory, The University of Tokyo (ISSL) and National Astronomical Observatory of Japan (NAO) have been developing a small infrared astrometry satellite named “Nano-JASMINE”. The satellite size is about 50cm cubic and 20kg, which plays a pre-cursor role of JASMINE Project which is programmed by NAO and JAXA. In addition, since there has been only one astrometry satellite HIPPARCOS by ESA in the past, Nano-JASMINE is also expected to achieve certain scientific results in the field of astrometry. In this project, ISSL aims to develop new advanced small satellite bus system whose performance is comparable to that of 100-500kg sized satellites, including attitude stability of 1 arc-second and thermal stability of the mission subsystem of 1 mK. This paper overviews the Nano-JASMINE bus system with emphasis on attitude and thermal control systems.

  14. Micro- and nano-structure based oligonucleotide sensors.

    PubMed

    Ferrier, David C; Shaver, Michael P; Hands, Philip J W

    2015-06-15

    This paper presents a review of micro- and nano-structure based oligonucleotide detection and quantification techniques. The characteristics of such devices make them very attractive for Point-of-Care or On-Site-Testing biosensing applications. Their small scale means that they can be robust and portable, their compatibility with modern CMOS electronics means that they can easily be incorporated into hand-held devices and their suitability for mass production means that, out of the different approaches to oligonucleotide detection, they are the most suitable for commercialisation. This review discusses the advantages of micro- and nano-structure based sensors and covers the various oligonucleotide detection techniques that have been developed to date. These include: Bulk Acoustic Wave and Surface Acoustic Wave devices, micro- and nano-cantilever sensors, gene Field Effect Transistors, and nanowire and nanopore based sensors. Oligonucleotide immobilisation techniques are also discussed.

  15. Nano concentration by acoustically generated complex spiral vortex field

    NASA Astrophysics Data System (ADS)

    Tang, Qiang; Wang, Xiaofei; Hu, Junhui

    2017-03-01

    A strategy to concentrate nanoscale materials on the boundary between a nano suspension droplet and non-vibration substrate is demonstrated and analyzed. It employs the spiral vortex of acoustic streaming, generated by an ultrasonically vibrating needle parallel to and above the non-vibration substrate. The vortex drags nanoscale materials to the center of itself, forming a concentration spot. For 250 nm-diameter SiO2 nano particle suspension with an initial concentration of 0.09 mg/ml, the diameter of the concentration spot can be up to several hundred microns. The dependency of the spiral vortex field on the vibration distribution of the acoustic needle in the droplet is also clarified by experiments and computation, and the concentration conditions are obtained by analyzing the nano particle dynamics in the spiral vortex.

  16. Gas sensing performance of nano zinc oxide sensors

    NASA Astrophysics Data System (ADS)

    Sharma, Shiva; Chauhan, Pratima

    2016-04-01

    We report nano Zinc Oxide (ZnO) synthesized by sol-gel method possessing the crystallite size which varies from 25.17 nm to 47.27 nm. The Scanning electron microscope (SEM) image confirms the uniform distribution of nanograins with high porosity. The Energy dispersion X-ray (EDAX) spectrum gives the atomic composition of Zn and O in ZnO powders and confirms the formation of nano ZnO particles. These factors reveals that Nano ZnO based gas sensors are highly sensitive to Ammonia gas (NH3) at room temperature, indicating the maximum response 86.8% at 800 ppm with fast response time and recovery time of 36 sec and 23 sec respectively.

  17. Near Infrared Fluorescent NanoGUMBOS for Biomedical Imaging

    PubMed Central

    Bwambok, David K.; El-Zahab, Bilal; Challa, Santhosh K.; Li, Min; Chandler, Lin; Baker, Gary A.; Warner, Isiah M.

    2009-01-01

    Herein, we report on near infrared (NIR) fluorescent nanoparticles generated from an emergent class of materials we refer to as a Group of Uniform Materials Based on Organic Salts (GUMBOS). GUMBOS are largely frozen ionic liquids, although the concept is more general and is also easily applied to solid ionic materials with melting points in excess of 100 °C. Nanoparticles based on GUMBOS (nanoGUMBOS) derived from a NIR fluorophore are prepared using a reprecipitation method and evaluated for in vivo fluorescence imaging. Due to their uniformity, single-step preparation, and composite nature, nanoGUMBOS help to resolve issues with dye leakage problems innate to alternate cellular stains and unlock a myriad of applications for these materials, highlighting exciting possibilities for multifunctional nanoGUMBOS. PMID:19928781

  18. Lasing in nano-grating with Fano resonance

    NASA Astrophysics Data System (ADS)

    Chen, Ya-Bin; Deng, Zi-Lan; Dong, Jian-Wen

    2016-10-01

    We propose a new scheme of lasing in a nano-grating with Fano resonance by the independent control of dark and bright modes. The controllability of both dark and bright modes can be achieved by fine-tuning the widths of two kinds of metallic stripes in the nano-grating. It enables the match between resonant frequencies of the nano-grating structure and the absorption and emission frequencies of gain medium. For example, changing the width of the thin strip is to hit the emission peak of the gain medium, while the fat strip corresponds to the absorption peak of the gain medium. We work out an optimal example of silver grating immersing Rhodamine dye, verifying the lasing dynamic process with minimum threshold and maximum output power. It may provide a new way on low-threshold and high-efficient plasmon laser.

  19. Laser short pulse heating of metal nano-wires

    NASA Astrophysics Data System (ADS)

    Yilbas, B. S.; Al-Dweik, A. Y.

    2012-11-01

    Non-equilibrium energy transfer takes place in a solid substrate during a short-pulse laser irradiation and temperature field can be obtained analytically in the irradiated region. In the present study, laser short-pulse heating of metal nano-wire is considered and the analytical solution for two-dimensional axisymmetric nano-wire is presented. Since the absorption of the incident beam takes place in the skin of the irradiated surface, a volumetric heat source resembling the absorption process is incorporated in the analysis. Three different nano-wire materials are introduced in the analysis for the comparison reason. These include silver, chromium, and copper. It is found that temperature decay is gradual on the surface vicinity and temporal variation of the surface temperature follows almost the laser pulse intensity profile at the irradiated center.

  20. Crystalline silicon solar cells with micro/nano texture

    NASA Astrophysics Data System (ADS)

    Dimitrov, Dimitre Z.; Du, Chen-Hsun

    2013-02-01

    Crystalline silicon solar cells with two-scale texture consisting of random upright pyramids and surface nanotextured layer directly onto the pyramids are prepared and reflectance properties and I-V characteristics measured. Random pyramids texture is produced by etching in an alkaline solution. On top of the pyramids texture, a nanotexture is developed using an electroless oxidation/etching process. Solar cells with two-scale surface texturization are prepared following the standard screen-printing technology sequence. The micro/nano surface is found to lower considerably the light reflectance of silicon. The short wavelengths spectral response (blue response) improvement is observed in micro/nano textured solar cells compared to standard upright pyramids textured cells. An efficiency of 17.5% is measured for the best micro/nano textured c-Si solar cell. The efficiency improvement is found to be due to the gain in both Jsc and Voc.

  1. Active Targeted Drug Delivery for Microbes Using Nano-Carriers

    PubMed Central

    Lin, Yung-Sheng; Lee, Ming-Yuan; Yang, Chih-Hui; Huang, Keng-Shiang

    2015-01-01

    Although vaccines and antibiotics could kill or inhibit microbes, many infectious diseases remain difficult to treat because of acquired resistance and adverse side effects. Nano-carriers-based technology has made significant progress for a long time and is introducing a new paradigm in drug delivery. However, it still has some challenges like lack of specificity toward targeting the infectious site. Nano-carriers utilized targeting ligands on their surface called ‘active target’ provide the promising way to solve the problems like accelerating drug delivery to infectious areas and preventing toxicity or side-effects. In this mini review, we demonstrate the recent studies using the active targeted strategy to kill or inhibit microbes. The four common nano-carriers (e.g. liposomes, nanoparticles, dendrimers and carbon nanotubes) delivering encapsulated drugs are introduced. PMID:25877093

  2. Theoretic analysis on electric conductance of nano-wire transistors

    NASA Astrophysics Data System (ADS)

    Tsai, N.-C.; Chiang, Y.-R.; Hsu, S.-L.

    2010-01-01

    By employing the commercial software nanoMos and Vienna ab Initio Simulation Package ( VASP), the performance of nano-wire field-effect transistors is investigated. In this paper, the Density-Gradient Model (DG Model) is used to describe the carrier transport behavior of the nano-wire transistor under quantum effects. The analysis of the drain current with respect to channel length, body dielectric constant and gate contact work function is presented. In addition, Fermi energy and DOS (Density of State) are introduced to explore the relative stability of carrier transport and electrical conductance for the silicon crystal with dopants. Finally, how the roughness of the surface of the silicon-based crystal is affected by dopants and their allocation can be illuminated by a few broken bonds between atoms near the skin of the crystal.

  3. Direct Analysis of Pharmaceutical Drugs Using Nano-DESI MS

    PubMed Central

    Cardoso-Palacios, Carlos

    2016-01-01

    Counterfeit pharmaceutical drugs imply an increasing threat to the global public health. It is necessary to have systems to control the products that reach the market and to detect falsified medicines. In this work, molecules in several pharmaceutical tablets were directly analyzed using nanospray desorption electrospray ionization mass spectrometry (nano-DESI MS). Nano-DESI is an ambient surface sampling technique which enables sampling of molecules directly from the surface of the tablets without any sample pretreatment. Both the active pharmaceutical ingredients (APIs) and some excipients were detected in all analyzed tablets. Principal component analysis was used to analyze mass spectral features from different tablets showing strong clustering between tablets with different APIs. The obtained results suggest nano-DESI MS as future tool for forensic analysis to discern APIs present in unknown tablet samples. PMID:27766177

  4. Control and Manipulation of Nano Cracks Mimicking Optical Wave

    NASA Astrophysics Data System (ADS)

    Suh, Young D.; Yeo, Junyeob; Lee, Habeom; Hong, Sukjoon; Kwon, Jinhyeong; Kim, Kyunkyu; Ko, Seung Hwan

    2015-11-01

    Generally, a fracture is considered as an uncontrollable thus useless phenomenon due to its highly random nature. The aim of this study is to investigate highly ordered cracks such as oscillatory cracks and to manipulate via elaborate control of mechanical properties of the cracking medium including thickness, geometry, and elastic mismatch. Specific thin film with micro-sized notches was fabricated on a silicon based substrate in order to controllably generate self-propagating cracks in large area. Interestingly, various nano-cracks behaved similar to optical wave including refraction, total internal reflection and evanescent wave. This novel phenomena of controlled cracking was used to fabricate sophisticated nano/micro patterns in large area which cannot be obtained even with conventional nanofabrication methods. We also have showed that the cracks are directly implementable into a nano/micro-channel application since the cracks naturally have a form of channel-like shape.

  5. Control and Manipulation of Nano Cracks Mimicking Optical Wave

    PubMed Central

    Suh, Young D.; Yeo, Junyeob; Lee, Habeom; Hong, Sukjoon; Kwon, Jinhyeong; Kim, Kyunkyu; Ko, Seung Hwan

    2015-01-01

    Generally, a fracture is considered as an uncontrollable thus useless phenomenon due to its highly random nature. The aim of this study is to investigate highly ordered cracks such as oscillatory cracks and to manipulate via elaborate control of mechanical properties of the cracking medium including thickness, geometry, and elastic mismatch. Specific thin film with micro-sized notches was fabricated on a silicon based substrate in order to controllably generate self-propagating cracks in large area. Interestingly, various nano-cracks behaved similar to optical wave including refraction, total internal reflection and evanescent wave. This novel phenomena of controlled cracking was used to fabricate sophisticated nano/micro patterns in large area which cannot be obtained even with conventional nanofabrication methods. We also have showed that the cracks are directly implementable into a nano/micro-channel application since the cracks naturally have a form of channel-like shape. PMID:26612107

  6. Damping Behavior of Alumina Epoxy Nano-Composites

    NASA Astrophysics Data System (ADS)

    Katiyar, Priyanka; Kumar, Anand

    2016-10-01

    Polymer nano composites, consisting of a polymer matrix with nanoparticle filler, have been predicted to be one of the most beneficial applications of nanotechnology. Addition of nano particulates to a polymer matrix enhances its performance by capitalizing on the nature and properties of the nano-scale fillers. The damping behavior of composites with nano structured phases is significantly different from that of micro structured materials. Viscoelastic homopolymer exhibit a high material damping response over a relatively narrow range of temperature and frequencies. In many practical situations, a polymeric structure is required to possess better strength and stiffness properties together with a reasonable damping behavior. Viscoelastic polymers show higher loss factor beyond the glassy region which comes with a significant drop in the specific modulus. Addition of nano alumina particles to epoxy leads to improved strength and stiffness properties with an increase in glass transition temperature while retaining its damping capability. Experimental investigations are carried out on composite beam specimen fabricated with different compositions of alumina nano particles in epoxy to evaluate loss factor, tan δ. Impact damping method is used for time response analysis. A single point Laser is used to record the transverse displacement of a point on the composite beam specimen. The experimental results are compared with theoretical estimation of loss factor using Voigt estimation. The effect of inter phase is included in theoretical estimation of loss factor. The result reveals that the study of interface properties is very important in deriving the overall loss factor of the composite since interface occupies a significant volume fraction in the composite.

  7. Anisotropic lanthanide-based nano-clusters for imaging applications.

    PubMed

    Yang, Xiaoping; Wang, Shiqing; King, Tyler L; Kerr, Christopher J; Blanchet, Clement; Svergun, Dmitri; Pal, Robert; Beeby, Andrew; Vadivelu, Jamuna; Brown, Katherine A; Jones, Richard A; Zhang, Lijie; Huang, Shaoming

    2016-10-06

    We have developed a new class of lanthanide nano-clusters that self-assemble using flexible Schiff base ligands. Cd-Ln and Ni-Ln clusters, [Ln8Cd24(L(1))12(OAc)39Cl7(OH)2] (Ln = Nd, Eu), [Eu8Cd24(L(1))12(OAc)44], [Ln8Cd24(L(2))12(OAc)44] (Ln = Nd, Yb, Sm) and [Nd2Ni4(L(3))2(acac)6(NO3)2(OH)2], were constructed using different types of flexible Schiff base ligands. These molecular nano-clusters exhibit anisotropic architectures that differ considerably depending upon the presence of Cd (nano-drum) or Ni (square-like nano-cluster). Structural characterization of the self-assembled particles has been undertaken using crystallography, transmission electron microscopy and small-angle X-ray scattering. Comparison of the metric dimensions of the nano-drums shows a consistency of size using these techniques, suggesting that these molecules may share similar structural features in both solid and solution states. Photophysical properties were studied by excitation of the ligand-centered absorption bands in the solid state and in solution, and using confocal microscopy of microspheres loaded with the compounds. The emissive properties of these compounds vary depending upon the combination of lanthanide and Cd or Ni present in these clusters. The results provide new insights into the construction of novel high-nuclearity nano-clusters and offer a promising foundation for the development of new functional nanomaterials.

  8. Effects of nano-TiO2 on the agronomically-relevant Rhizobium-legume symbiosis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of nano-TiO2 on Rhizobium-legume symbiosis was studied using garden peas and the compatible bacterial partner Rhizobium leguminosarum bv. viciae 3841. Exposure to nano-TiO2 did not affect the germination of peas grown aseptically, nor did it impact the gross root structure. However, nano-...

  9. Laboratory Assessment of Nano-Silver Transport in Sand Columns Using Complex Conductivity Measurements

    EPA Science Inventory

    Nano-materials are emerging into the global marketplace. Nano-particles, and other throwaway nano-devices may constitute a whole new class of non-biodegradable pollutants of which scientists have very little understanding. Therefore, the production of significant quantities of n...

  10. In Vitro Phototoxicity and Hazard Identification of Nano-scale Titanium Dioxide

    EPA Science Inventory

    Nano-titanium dioxide (nano-Ti02) catalyzes many reactions under UV radiation and is hypothesized to cause phototoxicity. A human-derived line of retinal pigment epithelial cells (ARPE-19) was treated with six different samples of nano-Ti02 and exposed to UVA radiation. The Ti02 ...

  11. Plasmon Nano-Optics: Designing Novel Nano-Tools for Biology and Medicine

    NASA Astrophysics Data System (ADS)

    Quidant, Romain

    Light plays a growing role in health science especially with the recent developments of new optical techniques that enable imaging biological processes down to the molecular scale and monitor dynamically physiological mechanisms in patients. In parallel, recent groundbreaking advances in nanotechnologies have opened new perspectives in medicine, for instance in creating new therapies or designing novel compact and highly sensitive diagnostic platforms. In this chapter, the aim is to discuss recent research that sits at the convergence of photonics, nanotechnology, and health. This research is based on the extraordinary optical properties of metallic nanoparticles (MNP) supporting Localized Surface Plasmon (LSP) (see Chap. 4 10.1007/978-3-642-28079-5_4".. We discuss how plasmonic MNP can be used as nano-sources of either light or heat for biological and medical applications.

  12. Magnetic Micro/Nano Structures for Biological Manipulation

    NASA Astrophysics Data System (ADS)

    Huang, Chen-Yu; Hsieh, Teng-Fu; Chang, Wei-Chieh; Yeh, Kun-Chieh; Hsu, Ming-Shinn; Chang, Ching-Ray; Chen, Jiann-Yeu; Wei, Zung-Hang

    2016-05-01

    Biomanipulation based on micro/nano structures is an attractive approach for biotechnology. To manipulate biological systems by magnetic forces, the magnetic labeling technology utilized magnetic nanoparticles (MNPs) as a common rule. Ferrofluid, well-dispersed MNPs, can be used for magnetic modification of the surface or as molds to form organized microstructures. For magnetic-based micro/nano structures, different methods to modulate magnetic field at the microscale have been developed. Specifically, this review focused on a new strategy which uses the concept of micromagnetism of patterned magnetic thin film with specific domain walls configurations to generate stable magnetic poles for cell patterning.

  13. Reliability analysis of fault-tolerant reconfigurable nano-architectures

    SciTech Connect

    Bhaduri, D.; Graham, P. S.; Shukla, S. K.

    2004-01-01

    Manufacturing defects and transient errors will be abundant in high - density reconfigurable nano-scale designs. Recently, we have automated a computational scheme based on Markov Random Field (MRF) and Belief Propagation algorithms in a tool named NANOLAB to evaluate the reliability of nano architectures. In this paper, we show how our methodology can be exploited to design defect- and fault-tolerant programmable logic architectures. The effectiveness of such automation is illustrated by analyzing reconfigurable Boolean networks formed using different industry-based configurable logic blocks (CLBs), both in the presence of thermal perturbations and signal noise.

  14. Calpain inhibitor nanocrystals prepared using Nano Spray Dryer B-90

    NASA Astrophysics Data System (ADS)

    Baba, Koichi; Nishida, Kohji

    2012-08-01

    The Nano Spray Dryer B-90 offers a new, simple, and alternative approach for the production of drug nanocrystals. Among attractive drugs, calpain inhibitor that inhibits programmed cell death `apoptosis' is a candidate for curing apoptosis-mediated intractable diseases such as Alzheimer's disease and Parkinson's disease. In this study, the preparation of calpain inhibitor nanocrystals using Nano Spray Dryer B-90 was demonstrated. The particle sizes were controlled by means of selecting mesh aperture sizes. The obtained average particle sizes were in the range of around 300 nm to submicron meter.

  15. Nano- and Microparticles in Welding Aerosol: Granulometric Analysis

    NASA Astrophysics Data System (ADS)

    Kirichenko, K. Yu.; Drozd, V. A.; Chaika, V. V.; Gridasov, A. V.; Kholodov, A. S.; Golokhvast, K. S.

    The paper presents the first results of the study of the size of particles appearing in the welding process by means of laser granulometry. It is shown that welding aerosol is the source of nano-and micro-sized particles extremely dangerous for human and animal health. Particle size distribution in the microrange was from 1 to 10 μm and up to 100%. It is shown that in 9 cases out of 28 with the use of various welding modes, welding rods and components the emission of aerosol with nano-sized particles (from 45.5% to 99.4%) is observed.

  16. Surgical Materials: Current Challenges and Nano-enabled Solutions

    PubMed Central

    Annabi, Nasim; Tamayol, Ali; Shin, Su Ryon; Ghaemmaghami, Amir M.; Peppas, Nicholas A.; Khademhosseini, Ali

    2014-01-01

    Surgical adhesive biomaterials have emerged as substitutes to sutures and staples in many clinical applications. Nano-enabled materials containing nanoparticles or having a distinct nanotopography have been utilized for generation of a new class of surgical materials with enhanced functionality. In this review, the state of the art in the development of conventional surgical adhesive biomaterials is critically reviewed and their shortcomings are outlined. Recent advancements in generation of nano-enabled surgical materials with their potential future applications are discussed. This review will open new avenues for the innovative development of the next generation of tissue adhesives, hemostats, and sealants with enhanced functionality for various surgical applications. PMID:25530795

  17. Ductility and work hardening in nano-sized metallic glasses

    SciTech Connect

    Chen, D. Z.; Gu, X. W.; An, Q.; Goddard, W. A.; Greer, J. R.

    2015-02-09

    In-situ nano-tensile experiments on 70 nm-diameter free-standing electroplated NiP metallic glass nanostructures reveal tensile true strains of ∼18%, an amount comparable to compositionally identical 100 nm-diameter focused ion beam samples and ∼3 times greater than 100 nm-diameter electroplated samples. Simultaneous in-situ observations and stress-strain data during post-elastic deformation reveal necking and work hardening, features uncharacteristic for metallic glasses. The evolution of free volume within molecular dynamics-simulated samples suggests a free surface-mediated relaxation mechanism in nano-sized metallic glasses.

  18. Electrical properties of epoxy resin based nano-composites

    SciTech Connect

    Tuncer, Enis; Sauers, Isidor; James, David Randy; Ellis, Alvin R; Paranthaman, Mariappan Parans; Aytug, Tolga; Sathyamurthy, Srivatsan; More, Karren Leslie; Li, Jing; Goyal, Amit

    2007-01-01

    We investigate the electrical properties of composite materials prepared as nano and sub-micro scale metal-oxide particles embedded in a commercial resin. The filler particles are barium titanate and calcium copper titanate. The physical and structural characteristics of constituents and the fabricated composites are reported. The electrical characterization of the composite samples are performed with the time- and frequency-domain dielectric spectroscopy techniques. The electrical breakdown strength of samples with nano and sub-micron size particles have better electrical insulation properties than the unfilled resin.

  19. Preparation and Characterization of Nano-CL-20 Explosive

    NASA Astrophysics Data System (ADS)

    Bayat, Yadollah; Zeynali, Vida

    2011-10-01

    Nano-CL-20 was prepared via precipitative crystallization by spraying a solution of CL-20 in a solvent (ethyl acetate) into a nonsolvent (isooctane). Scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) were used to characterize the appearance and the size of the particles. The results revealed that nano-CL-20 particles have the shape of spheres or ellipsoids with an average size of 95 nm. Due to their small diameter and high surface energy, the particles tended to agglomerate. Impact sensitivity of nanosize CL-20 was decreased in comparison to micrometer-size CL-20.

  20. Method for nano-pumping using carbon nanotubes

    DOEpatents

    Insepov, Zeke; Hassanein, Ahmed

    2009-12-15

    The present invention relates generally to the field of nanotechnology, carbon nanotubes and, more specifically, to a method and system for nano-pumping media through carbon nanotubes. One preferred embodiment of the invention generally comprises: method for nano-pumping, comprising the following steps: providing one or more media; providing one or more carbon nanotubes, the one or more nanotubes having a first end and a second end, wherein said first end of one or more nanotubes is in contact with the media; and creating surface waves on the carbon nanotubes, wherein at least a portion of the media is pumped through the nanotube.

  1. Nano-patterned superconducting surface for high quantum efficiency cathode

    DOEpatents

    Hannon, Fay; Musumeci, Pietro

    2017-03-07

    A method for providing a superconducting surface on a laser-driven niobium cathode in order to increase the effective quantum efficiency. The enhanced surface increases the effective quantum efficiency by improving the laser absorption of the surface and enhancing the local electric field. The surface preparation method makes feasible the construction of superconducting radio frequency injectors with niobium as the photocathode. An array of nano-structures are provided on a flat surface of niobium. The nano-structures are dimensionally tailored to interact with a laser of specific wavelength to thereby increase the electron yield of the surface.

  2. Mechanical, Electrical, and Environmental Evaluation of Nano-Miniature Connectors

    SciTech Connect

    Hilton, J.W.

    2001-07-30

    Because of their small size (0.025-inch spacing), nano-miniature connectors have been chosen for JTA telemetry applications. At the time they were chosen, extensive testing had not been done to determine the mechanical, electrical, and environmental characteristics of these connectors at the levels required for use by weapon systems. Since nano-miniature connectors use some unique plating and wire crimping processes not used in most design agency connectors, it was decided that these properties should be tested thoroughly. This report describes the results of that testing.

  3. Guided Self-Assembly of Nano-Precipitates into Mesocrystals

    PubMed Central

    Liu, H.; Gao, Y.; Xu, Z.; Zhu, Y.M.; Wang, Y.; Nie, J.F.

    2015-01-01

    We show by a combination of computer simulation and experimental characterization guided self-assembly of coherent nano-precipitates into a mesocrystal having a honeycomb structure in bulk materials. The structure consists of different orientation variants of a product phase precipitated out of the parent phase by heterogeneous nucleation on a hexagonal dislocation network. The predicted honeycomb mesocrystal has been confirmed by experimental observations in an Mg-Y-Nd alloy. The structure and lattice parameters of the mesocrystal and the size of the nano-precipitates are readily tuneable, offering ample opportunities to tailor its properties for a wide range of technological applications. PMID:26559002

  4. Raman spectroscopy of polyhedral carbon nano-onions

    NASA Astrophysics Data System (ADS)

    Codorniu Pujals, Daniel; Arias de Fuentes, Olimpia; Desdín García, Luis F.; Cazzanelli, Enzo; Caputi, Lorenzo S.

    2015-09-01

    The Raman spectra of polyhedral carbon nano-onions (PCO), obtained by underwater arc discharge of graphite electrodes, are studied. While the general Raman spectrum of PCO is very similar to those of other carbon nanostructures, including spherical nano-onions, the fine structure of the G and 2D bands gives valuable information that allows using Raman spectroscopy for differentiating the PCO from other carbon structures. The interpretation of the features of the fine structure of the spectra is supported by evidences obtained by TEM.

  5. Virus and Bacterial Cell Chemical Analysis by NanoSIMS

    SciTech Connect

    Weber, P; Holt, J

    2008-07-28

    In past work for the Department of Homeland Security, the LLNL NanoSIMS team has succeeded in extracting quantitative elemental composition at sub-micron resolution from bacterial spores using nanometer-scale secondary ion mass spectrometry (NanoSIMS). The purpose of this task is to test our NanoSIMS capabilities on viruses and bacterial cells. This initial work has proven successful. We imaged Tobacco Mosaic Virus (TMV) and Bacillus anthracis Sterne cells using scanning electron microscopy (SEM) and then analyzed those samples by NanoSIMS. We were able resolve individual viral particles ({approx}18 nm by 300 nm) in the SEM and extract correlated elemental composition in the NanoSIMS. The phosphorous/carbon ratio observed in TMV is comparable to that seen in bacterial spores (0.033), as was the chlorine/carbon ratio (0.11). TMV elemental composition is consistent from spot to spot, and TMV is readily distinguished from debris by NanoSIMS analysis. Bacterial cells were readily identified in the SEM and relocated in the NanoSIMS for elemental analysis. The Ba Sterne cells were observed to have a measurably lower phosphorous/carbon ratio (0.005), as compared to the spores produced in the same run (0.02). The chlorine/carbon ratio was approximately 2.5X larger in the cells (0.2) versus the spores (0.08), while the fluorine/carbon ratio was approximately 10X lower in the cells (0.008) than the spores (0.08). Silicon/carbon ratios for both cells and spores encompassed a comparable range. The initial data in this study suggest that high resolution analysis is useful because it allows the target agent to be analyzed separate from particulates and other debris. High resolution analysis would also be useful for trace sample analysis. The next step in this work is to determine the potential utility of elemental signatures in these kinds of samples. We recommend bulk analyses of media and agent samples to determine the range of media compositions in use, and to determine how

  6. A nano-silver enzyme electrode for organophosphorus pesticide detection.

    PubMed

    Zheng, Qiqi; Yu, Yonghua; Fan, Kai; Ji, Feng; Wu, Jian; Ying, Yibin

    2016-08-01

    A nano-silver electrode immobilizing acetylcholinesterase (AChE) for the detection of organophosphorus (OPPs) pesticides is reported. Scanning electron microscopy (SEM) was used to characterize the surface structure of two kinds of electrodes fabricated with different sizes of silver powders and the interface between chitosan layer and nano-silver powder layer. Cyclic voltammetry was carried out to characterize the response of silver/chitosan electrode in the absence and in the presence of thiocholine (TCh). It was also used to evaluate the insulativity of the chitosan layer. An amperometric method was performed to measure the response of the electrode to TCh, which is the product of the enzymatic reaction for detecting organophosphorus pesticides indirectly. Although there are many kinds of nanoparticles, silver was chosen for its internal advantage in detecting TCh at low potential without further modification. The result shows nano-silver powder has better performance than usual silver powder, and the limit of detection of paraoxon is 4 ppb under optimized conditions. One percent (w/v) chitosan solution was used as binder for the immobilization of nano-silver powder and AChE, which made it possible for independent electrode fabrication at room temperature, whereas 3% (w/v) chitosan solution was used as insulating compound for controlling the electrode area. Unlike traditional organic insulating ink, chitosan is safe and environmentally friendly, and it is used as insulating material for the first time. The flexible nano-silver/AChE/chitosan electrode was evaluated in Chinese chives and cabbage, and the recoveries of standard addition were 105.11 and 96.41%, respectively. Owing to the antibacterial property of nano-silver and the biocompatibility, safety, and biodegradability of chitosan, the proposed method is safe, facile, environmentally friendly, and has great potential in organophosphorus pesticide detection for food safety. Graphical Abstract Current

  7. From nano-plasmonic optics toward molecules bio-sensing

    NASA Astrophysics Data System (ADS)

    Su, Kai-Hung

    A systematic study on optical properties of nano-metallic particles was investigated. Nano metallic particle plasmon resonant peak wavelengths are significantly red-shifted from that of a single particle because of near-field coupling when two nano-particles are placed closer to each other. The shift decays approximately exponentially with increasing particle spacing and become negligible when the gap between the two particles exceeds about 2.5 times the particle short-axis length. While resonant peak of a finite 1D nano-particles chain is also significantly red-shifted, the peak wavelength is found to be non-monotonic and oscillating with the variation of the chain length. The results shown to occurs only for larger particles where phase retardation effects are important in plasmon coupling. Based on the coupling results from nano-particle interaction studies, we develop a new type of tunable plasmon resonance nano-particles, named tunable nano-plasmonic resonator (TNPR) which consists multi-layered Au/SiO2 nanodisks. Compared to single layered Au nanodisks, multilayered nanodisks TNPR exhibit several distinctive properties including significantly enhanced plasmon resonances and tunable resonance wavelengths which can be tailored to desired values by simply varying dielectric layer thickness while the particle diameter is kept constant. This tunable and augmented plasmon resonance holds a great potential in the applications of surface-enhanced Raman scattering (SERS). Characterized TNPR enhancement factor reaches as high as 4.7 x 10 10 for individual TNPRs, among the highest enhancement factor reported in single nanoparticle, indicating that our designed TNPR can serve as a great SERS active-substrate by matching the laser pumping frequency to maximize SERS enhancement. TNPR design was implemented for real bio-application. The sensitivity of non-optimized TNPR for in vitro proteolytic PSA assays reaches to 6pM. Compared to other cancer biomarker detection assays

  8. Guided Self-Assembly of Nano-Precipitates into Mesocrystals

    NASA Astrophysics Data System (ADS)

    Liu, H.; Gao, Y.; Xu, Z.; Zhu, Y. M.; Wang, Y.; Nie, J. F.

    2015-11-01

    We show by a combination of computer simulation and experimental characterization guided self-assembly of coherent nano-precipitates into a mesocrystal having a honeycomb structure in bulk materials. The structure consists of different orientation variants of a product phase precipitated out of the parent phase by heterogeneous nucleation on a hexagonal dislocation network. The predicted honeycomb mesocrystal has been confirmed by experimental observations in an Mg-Y-Nd alloy. The structure and lattice parameters of the mesocrystal and the size of the nano-precipitates are readily tuneable, offering ample opportunities to tailor its properties for a wide range of technological applications.

  9. Surgical Materials: Current Challenges and Nano-enabled Solutions.

    PubMed

    Annabi, Nasim; Tamayol, Ali; Shin, Su Ryon; Ghaemmaghami, Amir M; Peppas, Nicholas A; Khademhosseini, Ali

    2014-10-01

    Surgical adhesive biomaterials have emerged as substitutes to sutures and staples in many clinical applications. Nano-enabled materials containing nanoparticles or having a distinct nanotopography have been utilized for generation of a new class of surgical materials with enhanced functionality. In this review, the state of the art in the development of conventional surgical adhesive biomaterials is critically reviewed and their shortcomings are outlined. Recent advancements in generation of nano-enabled surgical materials with their potential future applications are discussed. This review will open new avenues for the innovative development of the next generation of tissue adhesives, hemostats, and sealants with enhanced functionality for various surgical applications.

  10. Anti-flammable vinyl ester resin nano-composite with nano-titania

    NASA Astrophysics Data System (ADS)

    Das, Rajib

    Anti-flammable material is a common expectation for any industry and household applications to protect the material from fire accident. Polymer composites also play a significant role in preparing anti flammable materials. Vinyl ester resins (VERs) are thermosetting resins that have excellent mechanical and thermal properties of epoxy resins and Nanotitania is an inexpensive, nontoxic and biocompatible inorganic material. In this paper to investigate the flame retardency of polymer nanocomposites VER is used as polymer matrix and TiO2 is used as inorganic nanofiller.3-[2-(2-aminoethylamino) ethylamino]propyl-trimethoxysilane (TATMS), a kind of silane is used as a coupling agent to functionalize the surface of nanoTiO2 to improve its flame retardency by adding Si and N2 group. TGA test and FTIR test have been performed and different peaks for Si and N2 in the modified nanofiller and weight loss of fabricated nanofiller confirmed that fabrication method was successful. After that, nanocomposite sample of VERs reinforced with nano TiO2 prepared and the effects of different loadings on mechanical and flame retardant properties are investigated after and before the modification of nanofillers. From tensile test result it is found that up to 5% loading of modified nanofiller the tensile strength is 62 MPa that is almost as same as pure VER and the tensile strength of unmodified nanofiller based PNC is 68 MPa which is not significant improvement in its mechanical property. From MCC test of flame retardancy it is found that the normalized heat release capacity of modified nanofiller based nanocomposite is decreased by 27.7% than unmodified nanofiller based PNC that is 9.8%. Also the normalized total heat release of modified nanofiller based PNC is 21.4% than unmodified PNC that is 12.4%.

  11. Wavelength tunable InGaN/GaN nano-ring LEDs via nano-sphere lithography

    NASA Astrophysics Data System (ADS)

    Wang, Sheng-Wen; Hong, Kuo-Bin; Tsai, Yu-Lin; Teng, Chu-Hsiang; Tzou, An-Jye; Chu, You-Chen; Lee, Po-Tsung; Ku, Pei-Cheng; Lin, Chien-Chung; Kuo, Hao-Chung

    2017-03-01

    In this research, nano-ring light-emitting diodes (NRLEDs) with different wall width (120 nm, 80 nm and 40 nm) were fabricated by specialized nano-sphere lithography technology. Through the thinned wall, the effective bandgaps of nano-ring LEDs can be precisely tuned by reducing the strain inside the active region. Photoluminescence (PL) and time-resolved PL measurements indicated the lattice-mismatch induced strain inside the active region was relaxed when the wall width is reduced. Through the simulation, we can understand the strain distribution of active region inside NRLEDs. The simulation results not only revealed the exact distribution of strain but also predicted the trend of wavelength-shifted behavior of NRLEDs. Finally, the NRLEDs devices with four-color emission on the same wafer were demonstrated.

  12. Wavelength tunable InGaN/GaN nano-ring LEDs via nano-sphere lithography

    PubMed Central

    Wang, Sheng-Wen; Hong, Kuo-Bin; Tsai, Yu-Lin; Teng, Chu-Hsiang; Tzou, An-Jye; Chu, You-Chen; Lee, Po-Tsung; Ku, Pei-Cheng; Lin, Chien-Chung; Kuo, Hao-Chung

    2017-01-01

    In this research, nano-ring light-emitting diodes (NRLEDs) with different wall width (120 nm, 80 nm and 40 nm) were fabricated by specialized nano-sphere lithography technology. Through the thinned wall, the effective bandgaps of nano-ring LEDs can be precisely tuned by reducing the strain inside the active region. Photoluminescence (PL) and time-resolved PL measurements indicated the lattice-mismatch induced strain inside the active region was relaxed when the wall width is reduced. Through the simulation, we can understand the strain distribution of active region inside NRLEDs. The simulation results not only revealed the exact distribution of strain but also predicted the trend of wavelength-shifted behavior of NRLEDs. Finally, the NRLEDs devices with four-color emission on the same wafer were demonstrated. PMID:28256529

  13. Thermite at the Nano-Scale

    NASA Astrophysics Data System (ADS)

    Mily, Edward Joseph, Jr.

    Physical vapor deposition of thin film thermites allow for a clean avenue for probing fundamental properties of nanoenergetic materials that prove difficult for traditional powder processing. Precise control over diffusion dimensions, microstructure, and total amount of material are able to be realized with this fabrication technique and the testing of such materials provide valuable insight into how oxidation occurs. This thesis provides several examples of how existing PVD techniques can be coupled with thermite constituents to further the energetic community's understanding of how oxidation occurs in the solid state with the variation of geometric and chemical alterations. The goal of these investigations was to elucidate which material properties and mechanisms drive exothermic activity. The thermite thin films of Al/CuO, Zr/CuO, and Mg/Cuo with varied reducing metal constituents were tested under slow heating conditions. The trend of the metal variation demonstrated the importance of terminal oxide diffusion properties in either impeding or enhancing oxygen exchange. When the reducing metal forms a terminal oxide with limited oxygen diffusivity, exothermicity requires elevated activation energies to commence self-sustaining reaction. In addition to the effects of chemical variation, bilayer thicknesses were varied and found to decrease exothermic peak temperatures similar to the trends found in intermetallic thin film energetics and powder energetic materials. The thin film thermites were also subjected to extreme initiation methods via laser driven flyer plate impact ignition and high heating rate heat treatment (105 K/s). General insight into nano thermite behavior at environments characteristic of applications was sought, and similar trends discovered among slow vs rapid testing. Decreasing reaction dimensions yielded higher reactivity and diffusion barrier properties role in impacting exothermic behavior persist to into the microsecond regime. Ultimately

  14. Growth of periodic nano-layers of nano-crystals of Au, Ag, Cu by ion beam

    NASA Technical Reports Server (NTRS)

    Smith, Cydale C.; Zheng, B.; Muntele, C. I.; Muntele, I. C.; Ila, D.

    2005-01-01

    Multilayered thin films of SiO2/AU+ SiO2/, SiO2/Ag+ SiO2/, and SiO2/Cu+ SiO2/, were grown by deposition. We have previously shown that MeV ion Bombardment of multi-nano-layers of SiO2/AU+ SiO2/ produces Au nanocrystals in the AU+ SiO2 layers. An increased number of nano-layers followed by MeV ion bombardment produces a wide optical absorption band, of which its FWHM depends on the number of nano-layers of SiO2/AU+ SiO2/. We have successfully repeated this process for nano-layers of SiO2/Ag+ SiO2/, and SiO2/Cu+ SiO2/. In this work we used 5 MeV Si as the post deposition bombardment ion and monitored the location as well as the optical absorption's FWHM for each layered structure using Optical Absorption Photospectrometry. The concentration and location of the metal nano-crystals were measured by Rutherford Backscattering Spectrometry. We will report on the results obtained for nano-layered structures produced by post deposition bombardment of SiO2/AU+ SiO2/, SiO2/Ag+ SiO2/, and SiO2/Cu+ SiO2/ layered systems as well as the results obtained from a system containing a periodic combination of SiO2/AU+ SiO2/, SiO2/Ag+ SiO2/, and SiO2/Cu+ SiO2/.

  15. Synthesis of SnO 2 micro-spheres, nano-rods and nano-flowers via simple hydrothermal route

    NASA Astrophysics Data System (ADS)

    Vuong, Dang Duc; Hien, Vu Xuan; Trung, Khuc Quang; Chien, Nguyen Duc

    2011-11-01

    SnO 2 micro-spheres (0.5-2 μm diameter), nano-flowers (petal size: 100-250 nm diameter; 500 nm-2 μm length) and nano-rods (3-6 nm diameter; 10-30 nm length) were synthesized by hydrothermal route. The samples were characterized by field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The influence of precursor, hydrothermal temperature and treatment time on the formation of SnO 2 multi-morphology was also investigated. Moreover, a possible formation mechanism and relationships among morphologies were discussed.

  16. Size dependent fluorescence tuning of naturally occurring betacyanin with silver nano particles

    NASA Astrophysics Data System (ADS)

    Sarkar, Arindam; Thankappan, Aparna; Nampoori, V. P. N.

    2014-10-01

    Light absorption and scattering of metal nano partilces occur in very narrow range of wavelengths. This is also dependent on the geometry and shape of metal nano particles. It is also known that scattering is related to (volume)2 and absorption is related to the volume of the spherical metal nano particles. In our work we show that using this principle metal nano particles enable fluorescence tuning of dyes. In our experiment we show such tuning in naturally occurring betacyanin extracted from red beetroot. We also show that such tuning is dependent on the size variation of the silver nano particles.

  17. High Temperature In Situ Compression of Thermoplastically Formed Nano-scale Metallic Glass

    NASA Astrophysics Data System (ADS)

    Mridha, Sanghita; Arora, Harpreet Singh; Lefebvre, Joseph; Bhowmick, Sanjit; Mukherjee, Sundeep

    2017-01-01

    The mechanical behavior of nano-scale metallic glasses was investigated by in situ compression tests in a scanning electron microscope. Platinum-based metallic glass nano-pillars were fabricated by thermoplastic forming. The nano-pillars and corresponding bulk substrate were tested in compression over the range of room temperature to glass transition. Stress-strain curves of the nano-pillars were obtained along with in situ observation of their deformation behavior. The bulk substrate as well as nano-pillars showed an increase in elastic modulus with temperature which is explained by diffusive rearrangement of atomic-scale viscoelastic units.

  18. Silicon Nano-well Arrays for Reliable Pattern Transfer and Locally Confined High Temperature Reactions

    PubMed Central

    Wi, Jung-Sub; Wilson, Robert J.; Lee, Donkoun; White, Robert M.; Wang, Shan X.

    2011-01-01

    Si nano-well arrays, with precisely controlled undercut Si sidewall profiles and flat bottomed pockets, enable uniform nanoscale pattern transfer from resists to metal deposits without degradation of the initial lithographic resolution, as verified by formation of arrays of Au nano-dots with 10 nm diameter. An additional functionality of the Si nano-wells as local nano-reactors, where the patterned material is enclosed in a Si pocket during high temperature reaction, is demonstrated by thermally inducing a phase transformation of the as-deposited A1 phase of FePt nano-dots to the high coercivity, chemically ordered L10 phase. PMID:21709347

  19. Doughnut-shaped peptide nano-assemblies and their applications as nanoreactors.

    PubMed

    Djalali, Ramin; Samson, Jacopo; Matsui, Hiroshi

    2004-06-30

    Doughnut-shaped nanoreactors, peptide nano-doughnuts, were self-assembled from peptides and organic Au salts. We demonstrated that monodisperse Au nanocrystals were synthesized inside the cavities of peptide nano-doughnuts by the reduction of Au ions and the size of the Au nanocrystal was controlled by the cavity dimension. The Au nanocrystals inside the nano-doughnuts were extracted by destroying the nano-doughnuts via long UV irradiation (>10 h). These features may allow the peptide nano-doughnuts to be applied in the fields of nanomaterial syntheses, controlled release systems, and drug delivery.

  20. Self-organized semiconductor nano-network on graphene.

    PubMed

    Son, Dabin; Jin Kim, Sang; Lee, Seungmin; Bae, Sukang; Kim, Tae-Wook; Kang, Jae-Wook; Hyun Lee, Sang

    2017-04-07

    A network structure consisting of nanomaterials with a stable structural support and charge path on a large area is desirable for various electronic and optoelectronic devices. Generally, network structures have been fabricated via two main strategies: (1) assembly of pre-grown nanostructures onto a desired substrate and (2) direct growth of nanomaterials onto a desired substrate. In this study, we utilized the surface defects of graphene to form a nano-network of ZnO via atomic layer deposition (ALD). The surface of pure and structurally perfect graphene is chemically inert. However, various types of point and line defects, including vacancies/adatoms, grain boundaries, and ripples in graphene are generated by growth, chemical or physical treatments. The defective sites enhance the chemical reactivity with foreign atoms. ZnO nanoparticles formed by ALD were predominantly deposited at the line defects and agglomerated with increasing ALD cycles. Due to the formation of the ZnO nano-network, the photocurrent between two electrodes was clearly changed under UV irradiation as a result of the charge transport between ZnO and graphene. The line patterned ZnO/graphene (ZnO/G) nano-network devices exhibit sensitivities greater than ten times those of non-patterned structures. We also confirmed the superior operation of a fabricated flexible photodetector based on the line patterned ZnO/G nano-network.

  1. Antimicrobial activity of organically modified nano-clays.

    PubMed

    Hong, Seek-In; Rhim, Jong-Whan

    2008-11-01

    Antimicrobial activity of three kinds of commercially available montmorillonite nano-clays including a naturally occurring one (Cloisite Na+) and two organically modified ones (Cloisite 20A and Cloisite 30B) against four representative pathogenic bacteria (two Gram-positive ones such as Staphylococcus aureus and Listeria monocytogenes, and two Gram-negative ones such as Salmonella typhimurium and E. coli O157:H7) was investigated. Antimicrobial activity was found to be dependent on the type of nano-clay and microorganisms tested. Among the nano-clays tested, Cloisite 30B showed the highest antibacterial activity followed by Cloisite 20A, however, the unmodified montmorillonite (Cloisite Na+) did not show any antibacterial activity. Especially, Cloisite 30B inactivated Gram-positive bacteria completely within an hour of incubation and inactivated Gram-negative bacteria by more than 2-3 log cycles after 8 hours incubation. SEM and TEM images of cell structure indicated that the organically modified nano-clay caused rupture of cell membrane and inactivation of the bacteria. This finding of antimicrobial activity of the organo-clay would open a new opportunity to develop polymer nanocomposites with additional functionality, i.e., antimicrobial function.

  2. Synthesis and Properties of Nano Zeolitic Imidazolate Frameworks

    SciTech Connect

    Nune, Satish K.; Thallapally, Praveen K.; Dohnalkova, Alice; Wang, Chong M.; Liu, Jun; Exarhos, Gregory J.

    2010-07-21

    Nano sized zeolitic imidazolate frameworks [nZIF-8] with excellent chemical and thermal stability has been synthesized at room temperature by simple mixing of 2-methylimidazole and zinc nitrate hexahydrate in methanol/ 1% high molecular weight poly(diallyldimethylammonium chloride) solution for 24 hrs

  3. A novel nano-carrier transdermal gel against inflammation.

    PubMed

    Chaudhary, Hema; Kohli, Kanchan; Kumar, Vikash

    2014-04-25

    The objective was to develop a stable, reproducible and patient non-infringing novel transdermal drug delivery system "nano-carrier transdermal gel" (NCTG) in combination of partial dose replacement of diclofenac diethylamine (DDEA) by curcumin (CRM). The drug content of gel was 99.30 and 97.57% for DDEA and CRM. Plasma samples were analyzed by liquid chromatography with triple-quadrupole tandem mass spectrometer (LC-MS/MS). Data were integrated with Analyst™ and analyzed by WinNonlin; stability parameters were analyzed using Tukey-Kramer multiple comparison test. Its average skin irritation scored 0.49 concluded to be non-irritant, safe for human use and in vivo studies revealed significantly greater extent of absorption and highly significant inhibition (%) of carrageenan induced paw edema. The results also demonstrated that encapsulation of drugs in nano-carrier increases its biological activity due to superior skin penetration potential. Hence, a novel once day transdermal gel of nano-carrier (nano-transfersomes; deformable vesicular) is achieved, to increase systemic availability, subsequent reduction in dose and toxicity of DDEA was developed for the treatment of inflammation.

  4. Multiplexed Sensing and Imaging with Colloidal Nano- and Microparticles

    NASA Astrophysics Data System (ADS)

    Carregal-Romero, Susana; Caballero-Díaz, Encarnación; Beqa, Lule; Abdelmonem, Abuelmagd M.; Ochs, Markus; Hühn, Dominik; Suau, Bartolome Simonet; Valcarcel, Miguel; Parak, Wolfgang J.

    2013-06-01

    Sensing and imaging with fluorescent, plasmonic, and magnetic colloidal nano- and microparticles have improved during the past decade. In this review, we describe the concepts and applications of how these techniques can be used in the multiplexed mode, that is, sensing of several analytes in parallel or imaging of several labels in parallel.

  5. Infinite Coordination Polymer Nano- and Micro-Particles

    DTIC Science & Technology

    2015-06-12

    SECURITY CLASSIFICATION OF: Infinite coordination polymer (ICP) particles and metal- organic frameworks (MOFs) are attractive materials for a diverse...Coordination Polymer Nano- and Micro- Particles Report Title Infinite coordination polymer (ICP) particles and metal- organic frameworks (MOFs) are...Abstract Infinite coordination polymer (ICP) particles and metal- organic frameworks (MOFs) are attractive materials for a diverse array of

  6. Nano-structured magnetic metamaterial with enhanced nonlinear properties

    PubMed Central

    Kobljanskyj, Yuri; Melkov, Gennady; Guslienko, Konstantin; Novosad, Valentyn; Bader, Samuel D.; Kostylev, Michael; Slavin, Andrei

    2012-01-01

    Nano-structuring can significantly modify the properties of materials. We demonstrate that size-dependent modification of the spin-wave spectra in magnetic nano-particles can affect not only linear, but also nonlinear magnetic response. The discretization of the spectrum removes the frequency degeneracy between the main excitation mode of a nano-particle and the higher spin-wave modes, having the lowest magnetic damping, and reduces the strength of multi-magnon relaxation processes. This reduction of magnon-magnon relaxation for the main excitation mode leads to a dramatic increase of its lifetime and amplitude, resulting in the intensification of all the nonlinear processes involving this mode. We demonstrate this experimentally on a two-dimensional array of permalloy nano-dots for the example of parametric generation of a sub-harmonic of an external microwave signal. The characteristic lifetime of this sub-harmonic is increased by two orders of magnitude compared to the case of a continuous magnetic film, where magnon-magnon relaxation limits the lifetime. PMID:22745899

  7. Prospects of nano-material in breast cancer management.

    PubMed

    Singh, A K; Pandey, A; Tewari, M; Kumar, R; Sharma, A; Pandey, H P; Shukla, H S

    2013-04-01

    Breast cancer evaluation and early diagnosis are core complexity worldwide and an ambiguity for scientists till date. Nano-materials are innovative tools for rapid diagnosis and therapy, which may induce an immense result in the field of oncology. Their exceptional size-dependent properties make them special and superior materials and quite indispensable in several fields of the human activities. The major obstacle in finding cure for malignant breast cancer is to increase in development of resistances for tumors to the therapeutic treatments. The widespread mammo-graph particle is being developed by nations to diagnosis disease in primitive stage to decline the mortality rates caused by breast carcinoma. The advancement of nano-particle based diagnostic tools facilitates in evaluation and provides encouraging development in breast cancer therapeutics. In this compact review, efforts have been made to compose the current advancements in the area of functional nano-particles. Furthermore, in vivo and in vitro applications of nano-materials in breast cancer management are also discussed.

  8. Nano-structured magnetic metamaterial with enhanced nonlinear properties.

    PubMed

    Kobljanskyj, Yuri; Melkov, Gennady; Guslienko, Konstantin; Novosad, Valentyn; Bader, Samuel D; Kostylev, Michael; Slavin, Andrei

    2012-01-01

    Nano-structuring can significantly modify the properties of materials. We demonstrate that size-dependent modification of the spin-wave spectra in magnetic nano-particles can affect not only linear, but also nonlinear magnetic response. The discretization of the spectrum removes the frequency degeneracy between the main excitation mode of a nano-particle and the higher spin-wave modes, having the lowest magnetic damping, and reduces the strength of multi-magnon relaxation processes. This reduction of magnon-magnon relaxation for the main excitation mode leads to a dramatic increase of its lifetime and amplitude, resulting in the intensification of all the nonlinear processes involving this mode. We demonstrate this experimentally on a two-dimensional array of permalloy nano-dots for the example of parametric generation of a sub-harmonic of an external microwave signal. The characteristic lifetime of this sub-harmonic is increased by two orders of magnitude compared to the case of a continuous magnetic film, where magnon-magnon relaxation limits the lifetime.

  9. Plasmonic nano-structures for optical data storage.

    PubMed

    Mansuripur, M; Zakharian, A R; Lesuffleur, A; Oh, Sang-Hyun; Jones, R J; Lindquist, N C; Im, Hyungsoon; Kobyakov, A; Moloney, J V

    2009-08-03

    We propose a method of optical data storage that exploits the small dimensions of metallic nano-particles and/or nano-structures to achieve high storage densities. The resonant behavior of these particles (both individually and in small clusters) in the presence of ultraviolet, visible, and near-infrared light may be used to retrieve pre-recorded information by far-field spectroscopic optical detection. In plasmonic data storage, a very short (approximately few femtoseconds) laser pulse is focused to a diffraction-limited spot over a small region of an optical disk containing metallic nano-structures. The digital data stored in each bit-cell, comprising multiple bits of information, modifies the spectrum of the incident light pulse. This spectrum is subsequently detected, upon reflection/transmission, with the aid of an optical spectrum analyzer. We present theoretical as well as preliminary experimental results that confirm the potential of plasmonic nano-structures for high-density optical data storage applications.

  10. Nano-imaging enabled via self-assembly

    PubMed Central

    McLeod, Euan; Ozcan, Aydogan

    2014-01-01

    SUMMARY Imaging object details with length scales below approximately 200 nm has been historically difficult for conventional microscope objective lenses because of their inability to resolve features smaller than one-half the optical wavelength. Here we review some of the recent approaches to surpass this limit by harnessing self-assembly as a fabrication mechanism. Self-assembly can be used to form individual nano- and micro-lenses, as well as to form extended arrays of such lenses. These lenses have been shown to enable imaging with resolutions as small as 50 nm half-pitch using visible light, which is well below the Abbe diffraction limit. Furthermore, self-assembled nano-lenses can be used to boost contrast and signal levels from small nano-particles, enabling them to be detected relative to background noise. Finally, alternative nano-imaging applications of self-assembly are discussed, including three-dimensional imaging, enhanced coupling from light-emitting diodes, and the fabrication of contrast agents such as quantum dots and nanoparticles. PMID:25506387

  11. Synthesis of Nano-Crystalline Gamma-TiAl Materials

    NASA Technical Reports Server (NTRS)

    Hales, Stephen J.; Vasquez, Peter

    2003-01-01

    One of the principal problems with nano-crystalline materials is producing them in quantities and sizes large enough for valid mechanical property evaluation. The purpose of this study was to explore an innovative method for producing nano-crystalline gamma-TiAl bulk materials using high energy ball milling and brief secondary processes. Nano-crystalline powder feedstock was produced using a Fritsch P4(TM) vario-planetary ball mill recently installed at NASA-LaRC. The high energy ball milling process employed tungsten carbide tooling (vials and balls) and no process control agents to minimize contamination. In a collaborative effort, two approaches were investigated, namely mechanical alloying of elemental powders and attrition milling of pre-alloyed powders. The objective was to subsequently use RF plasma spray deposition and short cycle vacuum hot pressing in order to effect consolidation while retaining nano-crystalline structure in bulk material. Results and discussion of the work performed to date are presented.

  12. Optical absorption and scattering spectroscopies of single nano-objects.

    PubMed

    Crut, Aurélien; Maioli, Paolo; Del Fatti, Natalia; Vallée, Fabrice

    2014-06-07

    Developments of optical detection and spectroscopy methods for single nano-objects are key advances for applications and fundamental understanding of the novel properties exhibited by nanosize systems. These methods are reviewed, focusing on far-field optical approaches based on light absorption and elastic scattering. The principles of the main linear and nonlinear methods are described and experimental results are illustrated in the case of metal nanoparticles, stressing the key role played by the object environment, such as the presence of a substrate, bound surface molecules or other nano-objects. Special attention is devoted to quantitative methods and correlation of the measured optical spectra of a nano-object with its morphology, characterized either optically or by electron microscopy, as this permits precise comparison with theoretical models. Application of these methods to optical detection and spectroscopy for single semiconductor nanowires and carbon nanotubes is also presented. Extension to ultrafast nonlinear extinction or scattering spectroscopies of single nano-objects is finally discussed in the context of investigation of their nonlinear optical response and their electronic, acoustic and thermal properties.

  13. Self-assembled Nano-layering at the Adhesive interface.

    PubMed

    Yoshida, Y; Yoshihara, K; Nagaoka, N; Hayakawa, S; Torii, Y; Ogawa, T; Osaka, A; Meerbeek, B Van

    2012-04-01

    According to the 'Adhesion-Decalcification' concept, specific functional monomers within dental adhesives can ionically interact with hydroxyapatite (HAp). Such ionic bonding has been demonstrated for 10-methacryloyloxydecyl dihydrogen phosphate (MDP) to manifest in the form of self-assembled 'nano-layering'. However, it remained to be explored if such nano-layering also occurs on tooth tissue when commercial MDP-containing adhesives (Clearfil SE Bond, Kuraray; Scotchbond Universal, 3M ESPE) were applied following common clinical application protocols. We therefore characterized adhesive-dentin interfaces chemically, using x-ray diffraction (XRD) and energy-dispersive x-ray spectroscopy (EDS), and ultrastructurally, using (scanning) transmission electron microscopy (TEM/STEM). Both adhesives revealed nano-layering at the adhesive interface, not only within the hybrid layer but also, particularly for Clearfil SE Bond (Kuraray), extending into the adhesive layer. Since such self-assembled nano-layering of two 10-MDP molecules, joined by stable MDP-Ca salt formation, must make the adhesive interface more resistant to biodegradation, it may well explain the documented favorable clinical longevity of bonds produced by 10-MDP-based adhesives.

  14. Quantum behavior of water nano-confined in beryl

    NASA Astrophysics Data System (ADS)

    Finkelstein, Y.; Moreh, R.; Shang, S. L.; Wang, Y.; Liu, Z. K.

    2017-03-01

    The proton mean kinetic energy, Ke(H), of water confined in nanocavities of beryl (Be3Al2Si6O18) at 5 K was obtained by simulating the partial vibrational density of states from density functional theory based first-principles calculations. The result, Ke(H) = 104.4 meV, is in remarkable agreement with the 5 K deep inelastic neutron scattering (DINS) measured value of 105 meV. This is in fact the first successful calculation that reproduces an anomalous DINS value regarding Ke(H) in nano-confined water. The calculation indicates that the vibrational states of the proton of the nano-confined water molecule distribute much differently than in ordinary H2O phases, most probably due to coupling with lattice modes of the hosting beryl nano-cage. These findings may be viewed as a promising step towards the resolution of the DINS controversial measurements on other H2O nano-confining systems, e.g., H2O confined in single and double walled carbon nanotubes.

  15. Oleic acid coated magnetic nano-particles: Synthesis and characterizations

    SciTech Connect

    Panda, Biswajit Goyal, P. S.

    2015-06-24

    Magnetic nano particles of Fe{sub 3}O{sub 4} coated with oleic acid were synthesized using wet chemical route, which involved co-precipitation of Fe{sup 2+} and Fe{sup 3+} ions. The nano particles were characterized using XRD, TEM, FTIR, TGA and VSM. X-ray diffraction studies showed that nano particles consist of single phase Fe{sub 3}O{sub 4} having inverse spinel structure. The particle size obtained from width of Bragg peak is about 12.6 nm. TEM analysis showed that sizes of nano particles are in range of 6 to 17 nm with a dominant population at 12 - 14 nm. FTIR and TGA analysis showed that -COOH group of oleic acid is bound to the surface of Fe{sub 3}O{sub 4} particles and one has to heat the sample to 278° C to remove the attached molecule from the surface. Further it was seen that Fe{sub 3}O{sub 4} particles exhibit super paramagnetism with a magnetization of about 53 emu/ gm.

  16. Reduced immune cell responses on nano and submicron rough titanium.

    PubMed

    Lu, Jing; Webster, Thomas J

    2015-04-01

    Current bare metal stents can be improved by nanotechnology to support the simultaneous acceleration of endothelialization and consequent reduction of immune cell responses after implantation. In our prior study, electron beam deposition was utilized to create different scales of roughness on titanium stents including flat (F-Ti), a mixture of nanometer and submicron (S-Ti), and nanometer (N-Ti). Enhanced endothelial responses (adhesion, migration, and nitric acid/endothelin-1 secretion) on nanometer to submicron rough titanium were observed compared to flat titanium. The present study aimed to further investigate the influence of nano and submicron titanium surface features on immune cells. Initial monocyte adhesion was found to be reduced on nano and submicron surface features compared to a flat surface. In a model including both endothelial cells and monocytes, it was proven that the submicron surface gave rise to an endothelial cell monolayer which generated the highest amount of NOx and subsequently led to decreased adhesiveness of endothelial cells to monocytes. The analysis of monocyte morphology gave hints to less differentiated monocytes on a submicron surface. Furthermore, the adhesion of and pro-inflammatory cytokine release from macrophages were all reduced on nano and submicron titanium surface features compared to a flat surface. This study, thus, suggests that nano and submicron titanium surfaces should be further studied for improved vascular stent performance.

  17. "transistor-like" spin nano-switches: Physics and applications

    NASA Astrophysics Data System (ADS)

    Diep, Vinh Quang

    Progress in the last two decades has effectively integrated spintronics and nanomagnetics into a single field, creating a new class of spin-based devices that are now being widely used in magnetic memory devices. However, it is not clear if these advances could also be used to build logic devices. The objective of this thesis is three-fold: The first is to describe a general paradigm for combining Read and Write units used in memory devices into transistor like nano-switches having input-output isolation and gain. Such switches could be used to build logic circuits without the need of any external circuits or amplification. The second is to describe an experimentally benchmarked simulation model for designing a concrete implementation of a transistor-like switch based on: Giant Spin Hall Effect (Write), Magnetic Tunnel Junction (Read) and magnetic coupling for isolation. It turns out that the model can also be used to analyze/design stray fields in perpendicular magnetic tunnel junction (pMTJ), an important problem in scaled pMTJ devices. The third is to discuss the novel features and possible new class of circuits of spin nano-switches. We will first describe a spin switch nano-oscillator based on the standard principle of incorporating feedback into a device with gain. We then discuss how spin nano-switches can be used to implement different types of neural networks such as second generation, third generation and deep belief neural networks.

  18. Magnetite nano-islands on silicon-carbide with graphene

    DOE PAGES

    Anderson, Nathaniel A.; Zhang, Qiang; Hupalo, Myron; ...

    2017-01-05

    X-ray magnetic circular dichroism (XMCD) measurements of iron nano-islands grown on graphene and covered with a Au film for passivation reveal that the oxidation through defects in the Au film spontaneously leads to the formation of magnetite nano-particles (i.e, Fe3O4). The Fe nano-islands (20 and 75 monolayers; MLs) are grown on epitaxial graphene formed by thermally annealing 6HSiC( 0001) and subsequently covered, in the growth chamber, with nominal 20 layers of Au. Our X-ray absorption spectroscopy and XMCD measurements at applied magnetic fields show that the thin film (20 ML) is totally converted to magnetite whereas the thicker lm (75more » ML) exhibits properties of magnetite but also those of pure metallic iron. Temperature dependence of the XMCD signal (of both samples) shows a clear transition at TV ≈ 120 K consistent with the Verwey transition of bulk magnetite. These results have implications on the synthesis of magnetite nano-crystals and also on their regular arrangements on functional substrates such as graphene.« less

  19. Secondary NanoSpacecraft Survey of the Martian Moons

    NASA Astrophysics Data System (ADS)

    Klesh, A. T.; Castillo-Rogez, J. C.

    2012-06-01

    We propose the deployment of multiple NanoSats at Phobos with an ESPA-ring class mothership to provide a massive spectrum of investigations at a very low cost. PIs could fly focused missions with miniaturized instruments for targeted science.

  20. Nano-scale processes behind ion-beam cancer therapy

    NASA Astrophysics Data System (ADS)

    Surdutovich, Eugene; Garcia, Gustavo; Mason, Nigel; Solov'yov, Andrey V.

    2016-04-01

    This topical issue collates a series of papers based on new data reported at the third Nano-IBCT Conference of the COST Action MP1002: Nanoscale Insights into Ion Beam Cancer Therapy, held in Boppard, Germany, from October 27th to October 31st, 2014. The Nano-IBCT COST Action was launched in December 2010 and brought together more than 300 experts from different disciplines (physics, chemistry, biology) with specialists in radiation damage of biological matter from hadron-therapy centres, and medical institutions. This meeting followed the first and the second conferences of the Action held in October 2011 in Caen, France and in May 2013 in Sopot, Poland respectively. This conference series provided a focus for the European research community and has highlighted the pioneering research into the fundamental processes underpinning ion beam cancer therapy. Contribution to the Topical Issue "COST Action Nano-IBCT: Nano-scale Processes Behind Ion-Beam Cancer Therapy", edited by Andrey V. Solov'yov, Nigel Mason, Gustavo Garcia and Eugene Surdutovich.

  1. Optical recoil of asymmetric nano-optical antenna.

    PubMed

    Song, Jung-Hwan; Shin, Jonghwa; Lim, Hee-Jin; Lee, Yong-Hee

    2011-08-01

    We propose nano-optical antennas with asymmetric radiation patterns as light-driven mechanical recoil force generators. Directional antennas are found to generate recoil force efficiently when driven in the spectral proximity of their resonances. It is also shown that the recoil force is equivalent to the Poynting vector integrated over a closed sphere containing the antenna structures.

  2. Measuring scientific research in emerging nano-energy field

    NASA Astrophysics Data System (ADS)

    Guan, Jiancheng; Liu, Na

    2014-04-01

    The purpose of this paper is to comprehensively explore scientific research profiles in the field of emerging nano-energy during 1991-2012 based on bibliometrics and social network analysis. We investigate the growth pattern of research output, and then carry out across countries/regions comparisons on research performances. Furthermore, we examine scientific collaboration across countries/regions by analyzing collaborative intensity and networks in 3- to 4-year intervals. Results indicate with an impressively exponential growth pattern of nano-energy articles, the world share of scientific "giants," such as the USA, Germany, England, France and Japan, display decreasing research trends, especially in the USA. Emerging economies, including China, South Korea and India, exhibit a rise in terms of the world share, illustrating strong development momentum of these countries in nano-energy research. Strikingly, China displays a remarkable rise in scientific influence rivaling Germany, Japan, France, and England in the last few years. Finally, the scientific collaborative network in nano-energy research has expanded steadily. Although the USA and several major European countries play significantly roles on scientific collaboration, China and South Korea exert great influence on scientific collaboration in recent years. The findings imply that emerging economies can earn competitive advantages in some emerging fields by properly engaging a catch-up strategy.

  3. Self-organized semiconductor nano-network on graphene

    NASA Astrophysics Data System (ADS)

    Son, Dabin; Kim, Sang Jin; Lee, Seungmin; Bae, Sukang; Kim, Tae-Wook; Kang, Jae-Wook; Lee, Sang Hyun

    2017-04-01

    A network structure consisting of nanomaterials with a stable structural support and charge path on a large area is desirable for various electronic and optoelectronic devices. Generally, network structures have been fabricated via two main strategies: (1) assembly of pre-grown nanostructures onto a desired substrate and (2) direct growth of nanomaterials onto a desired substrate. In this study, we utilized the surface defects of graphene to form a nano-network of ZnO via atomic layer deposition (ALD). The surface of pure and structurally perfect graphene is chemically inert. However, various types of point and line defects, including vacancies/adatoms, grain boundaries, and ripples in graphene are generated by growth, chemical or physical treatments. The defective sites enhance the chemical reactivity with foreign atoms. ZnO nanoparticles formed by ALD were predominantly deposited at the line defects and agglomerated with increasing ALD cycles. Due to the formation of the ZnO nano-network, the photocurrent between two electrodes was clearly changed under UV irradiation as a result of the charge transport between ZnO and graphene. The line patterned ZnO/graphene (ZnO/G) nano-network devices exhibit sensitivities greater than ten times those of non-patterned structures. We also confirmed the superior operation of a fabricated flexible photodetector based on the line patterned ZnO/G nano-network.

  4. Fiber-Reinforced Reactive Nano-Epoxy Composites

    NASA Technical Reports Server (NTRS)

    Zhong, Wei-Hong

    2011-01-01

    An ultra-high-molecular-weight polyethylene/ matrix interface based on the fabrication of a reactive nano-epoxy matrix with lower surface energy has been improved. Enhanced mechanical properties versus pure epoxy on a three-point bend test include: strength (25 percent), modulus (20 percent), and toughness (30 percent). Increased thermal properties include higher Tg (glass transition temperature) and stable CTE (coefficient of thermal expansion). Improved processability for manufacturing composites includes faster wetting rates on macro-fiber surfaces, lower viscosity, better resin infusion rates, and improved rheological properties. Improved interfacial adhesion properties with Spectra fibers by pullout tests include initial debonding force of 35 percent, a maximum pullout force of 25 percent, and energy to debond at 65 percent. Improved mechanical properties of Spectra fiber composites (tensile) aging resistance properties include hygrothermal effects. With this innovation, high-performance composites have been created, including carbon fibers/nano-epoxy, glass fibers/nano-epoxy, aramid fibers/ nano-epoxy, and ultra-high-molecularweight polyethylene fiber (UHMWPE).

  5. Examining the Societal Impacts of Nanotechnology through Simulation: NANO SCENARIO

    ERIC Educational Resources Information Center

    Jarmon, Leslie; Keating, Elizabeth; Toprac, Paul

    2008-01-01

    This article describes a university-sponsored experiential-based simulation, the NANO SCENARIO, to increase the public's awareness and affect attitudes on the societal implications of nanoscience and nanotechnology by bringing together diverse stakeholders' perspectives in a participatory learning environment. Nanotechnology has the potential for…

  6. Theoretical Study on Nano-Catalyst Burn Rate

    DTIC Science & Technology

    2014-11-26

    energetic materials, within this project the computer aided design and property prediction of titania -based nano-catalysts have been performed using first...AP molecule are equal to 1.52 eV and 0.88 eV, respectively. The stronger interaction is associated with the presence of OH group on titania surface

  7. Nano-Composite Material Development for 3-D Printers

    SciTech Connect

    Satches, Michael Randolph

    2015-10-14

    The objectives of the project was to create a graphene reinforced polymer nano-composite viable in a commercial 3-D printer; study the effects of ultra-high loading of graphene in polymer matrices; and determine the functional upper limit of graphene loading.

  8. Soft-Nano-Materials: Extreme Mechanics at Extreme Length Scales

    NASA Astrophysics Data System (ADS)

    Zhao, Xuanhe

    2013-03-01

    Over decades of intensive research, various technologies have been developed to manufacture large-scale nanomaterials such as nanoparticles, quantum dots, nanowires, carbon nanotubes, biomolecules, nanofilms, and graphene. Meanwhile, extraordinary properties and functionalities of nanomaterials have been demonstrated by harnessing their deformations and instabilities coupled with their small length scales. However, a grand challenge still exists on how to control the deformations and instabilities of large-scale nanomaterials for scaling-up functions and applications that can impact the society. An emerging paradigm that addresses this challenge is by using soft materials such as polymers, gels and biomaterials to assemble large amounts of nanomaterials and regulate their deformations and instabilities in controlled manners. Successful examples range from nanostructured tissues such as bones and cartilages found in nature to polymer composites with nanowire/nanotube/graphene, flexible electronics, nano-generators and nano-batteries. This talk is focused on extreme mechanics of these soft-nano-materials and systems. We will discuss large deformation, instabilities, and fractures of one-dimensional and two dimensional nanomaterials, such as nanowires and graphene, interacting with matrices of soft materials. We will further illustrate extraordinary properties and functions achieved by understanding and exploiting the extreme mechanics of soft-nano-materials and systems.

  9. Nano-optical conveyor belt with waveguide-coupled excitation.

    PubMed

    Wang, Guanghui; Ying, Zhoufeng; Ho, Ho-pui; Huang, Ying; Zou, Ningmu; Zhang, Xuping

    2016-02-01

    We propose a plasmonic nano-optical conveyor belt for peristaltic transport of nano-particles. Instead of illumination from the top, waveguide-coupled excitation is used for trapping particles with a higher degree of precision and flexibility. Graded nano-rods with individual dimensions coded to have resonance at specific wavelengths are incorporated along the waveguide in order to produce spatially addressable hot spots. Consequently, by switching the excitation wavelength sequentially, particles can be transported to adjacent optical traps along the waveguide. The feasibility of this design is analyzed using three-dimensional finite-difference time-domain and Maxwell stress tensor methods. Simulation results show that this system is capable of exciting addressable traps and moving particles in a peristaltic fashion with tens of nanometers resolution. It is the first, to the best of our knowledge, report about a nano-optical conveyor belt with waveguide-coupled excitation, which is very important for scalability and on-chip integration. The proposed approach offers a new design direction for integrated waveguide-based optical manipulation devices and its application in large scale lab-on-a-chip integration.

  10. [Recent topics about nano-safety science and its future].

    PubMed

    Yoshioka, Yasuo; Yoshikawa, Tomoaki; Nabeshi, Hiromi; Tsutsumi, Yasuo

    2013-01-01

    Recently, it is concerned that nanomaterials induce undesirable biological responses (NanoTox) which is different from conventional materials attributed to their unique physicochemical properties in the world. Therefore, the movements to regulate the development and practical use of nanomaterials are accelerated in North America and Europe in corporation with Organisation for Economic Co-operation and Development (OECD). However, for our enjoying the benefits of nanomateirals, it is most important not to regulate nanomaterials in the blind way but to assure the security of nanomaterials and support the development of nanomaterial industries. These are duty of our country to be advanced country, technology-oriented nation and intellectual property nation. From these viewpoints, we are engaged on not NanoTox study but Nano-Safety Science study. That is, we try to research the relationship between physicochemical properties, biodistribution, intracellular localization, kinetics and biological responses (safety) of nanomaterials for the purpose of the collection and the transmission of safety information of nanomaterials based on scientific evidence lead to a support of nanomaterials' development. In this review, we would like to introduce our Nano-safety science study using mainly amorphous silica nanoparticles.

  11. Microwave irradiation on carbon black: Studies on the transformation of particles into nano-balls, nano-sticks and nano-onion like structures

    NASA Astrophysics Data System (ADS)

    Asokan, Vijayshankar; Venkatachalapathy, Vishnukanthan; Rajavel, Krishnamoorthy; Madsen, Dorte Nørgaard

    2016-12-01

    The solid-state transformation behavior of carbon black (CB) nanoparticles after irradiated with microwave energy was studied with and without influence of a metal catalyst. The CB sample was exposed to microwave radiation at power of 900 W from the oven and collected after 15 min and after 30 min and 45 min of irradiation. The samples were characterized using X-ray diffraction measurements, Raman spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy (HRTEM) and thermogravimetric analysis. Characterization of the samples prepared without catalyst shows that microwave irradiation can transform CB nanoparticles into nano-balls and nano-stick like structures. While nanoballs of almost 300-500 nm diameter are visible in all the samples irrespective of microwave irradiation time, amorphous nano-stick like structure are present only in the sample collected after 30 min of microwave irradiation. CB irradiated together with a metal catalyst resulted in metal-encapsulated onion like structures with perfectly arranged graphene layers.

  12. Nano Structured Plasma Spray Coating for Wear and High Temperature Corrosion Resistance Applications

    NASA Astrophysics Data System (ADS)

    Ghosh, D.; Shukla, A. K.; Roy, H.

    2014-04-01

    The nano structured coating is a major challenge today to improve the different mechanical properties, wear and high temperature corrosion resistance behaviour of different industrial alloys. This paper is a review on synthesis of nano powder, plasma spraying methods, techniques of nano structured coating by plasma spray method, mechanical properties, tribological properties and high temperature corrosion behaviour of nano structured coating. Nano structured coatings of ceramic powders/composites are being developed for wide variety of applications like boiler, turbine and aerospace industries, which requires the resistance against wear, corrosion, erosion etc. The nano sized powders are subjected to agglomeration by spray drying, after which nano structured coating can be successfully applied over the substrate. Nano structured coating shows improved mechanical wear resistance and high temperature corrosion resistance. The significant improvement of wear and corrosion resistance is mainly attributed to formation of semi molten nano zones in case of nano structured coatings. The future scope of application of nano structured coating has also been highlighted in this paper.

  13. Removing Pathogens Using Nano-Ceramic-Fiber Filters

    NASA Technical Reports Server (NTRS)

    Tepper, Frederick; Kaledin, Leonid

    2005-01-01

    A nano-aluminum-oxide fiber of only 2 nanometers in diameter was used to develop a ceramic-fiber filter. The fibers are electropositive and, when formulated into a filter material (NanoCeram(TradeMark)), would attract electro-negative particles such as bacteria and viruses. The ability to detect and then remove viruses as well as bacteria is of concern in space cabins since they may be carried onboard by space crews. Moreover, an improved filter was desired that would polish the effluent from condensed moisture and wastewater, producing potable drinking water. A laboratory- size filter was developed that was capable of removing greater than 99.9999 percent of bacteria and virus. Such a removal was achieved at flow rates hundreds of times greater than those through ultraporous membranes that remove particles by sieving. Because the pore size of the new filter was rather large as compared to ultraporous membranes, it was found to be more resistant to clogging. Additionally, a full-size cartridge is being developed that is capable of serving a full space crew. During this ongoing effort, research demonstrated that the filter media was a very efficient adsorbent for DNA (deoxyribonucleic acid), RNA (ribonucleic acid), and endotoxins. Since the adsorption is based on the charge of the macromolecules, there is also a potential for separating proteins and other particulates on the basis of their charge differences. The separation of specific proteins is a major new thrust of biotechnology. The principal application of NanoCeram filters is based on their ability to remove viruses from water. The removal of more than 99.9999 percent of viruses was achieved by a NanoCeram polishing filter added to the effluent of an existing filtration device. NanoCeram is commercially available in laboratory-size filter discs and in the form of a syringe filter. The unique characteristic of the filter can be demonstrated by its ability to remove particulate dyes such as Metanyl yellow. Its

  14. Data Encoding using Periodic Nano-Optical Features

    NASA Astrophysics Data System (ADS)

    Vosoogh-Grayli, Siamack

    Successful trials have been made through a designed algorithm to quantize, compress and optically encode unsigned 8 bit integer values in the form of images using Nano optical features. The periodicity of the Nano-scale features (Nano-gratings) have been designed and investigated both theoretically and experimentally to create distinct states of variation (three on states and one off state). The use of easy to manufacture and machine readable encoded data in secured authentication media has been employed previously in bar-codes for bi-state (binary) models and in color barcodes for multiple state models. This work has focused on implementing 4 states of variation for unit information through periodic Nano-optical structures that separate an incident wavelength into distinct colors (variation states) in order to create an encoding system. Compared to barcodes and magnetic stripes in secured finite length storage media the proposed system encodes and stores more data. The benefits of multiple states of variation in an encoding unit are 1) increased numerically representable range 2) increased storage density and 3) decreased number of typical set elements for any ergodic or semi-ergodic source that emits these encoding units. A thorough investigation has targeted the effects of the use of multi-varied state Nano-optical features on data storage density and consequent data transmission rates. The results show that use of Nano-optical features for encoding data yields a data storage density of circa 800 Kbits/in2 via the implementation of commercially available high resolution flatbed scanner systems for readout. Such storage density is far greater than commercial finite length secured storage media such as Barcode family with maximum practical density of 1kbits/in2 and highest density magnetic stripe cards with maximum density circa 3 Kbits/in2. The numerically representable range of the proposed encoding unit for 4 states of variation is [0 255]. The number of

  15. Fundamental formulations and recent achievements in piezoelectric nano-structures: a review.

    PubMed

    Fang, Xue-Qian; Liu, Jin-Xi; Gupta, Vijay

    2013-03-07

    Piezoelectric nano-structures have been regarded as the next-generation piezoelectric material due to their inherent nano-sized piezoelectricity. This review summarizes the recent theoretical and experimental findings in piezoelectric nano-structures, including piezoelectric nanowires, nanoplates, nanobeams, nanofilms, nanoparticles, and piezoelectric heterogeneous materials containing piezoelectric nano-inhomogeneities. To begin, the types of piezoelectric nano-structured materials and the wide application of piezoelectric nano-structures in recent years are delineated. Next, the theoretical foundations including the definition of surface stress and electric displacement, the surface constitutive relations, the surface equilibrium equations, and nonlocal piezoelectricity, and their applications, are illustrated. Then, the effective mechanical and piezoelectric properties are depicted. Furthermore, the experimental investigations are classified, and some important observations are discussed. Finally, the perspectives and challenges for the future development of piezoelectric nano-structures are pointed out.

  16. Application of nano-structured conducting polymers to humidity sensing

    NASA Astrophysics Data System (ADS)

    Park, Pilyeon

    Nanostructures, such as nanowires, nanocolumns, and nanotubes, have attracted a lot of attention because of their huge potential impact on a variety of applications. For sensor applications, nanostructures provide high surface area to volume ratios. The high surface area to volume ratio allows more reaction areas between target species and detection materials and also improves the detection sensitivity and response time. The main goal of this research was to exploit the advantages and develop innovative methods to accomplish the synthesis of nanowires and nano-coulmn conducting polymers used in humidity detection. To accomplish this, two fabrication methods are used. The first one utilizes the geometric confinement effect of a temporary nanochannel template to orient, precisely position, and assemble Polyaniline (PANI) nanowires as they are synthesized. The other approach is to simply spin-coat a polymer onto a substrate, and then oxygen plasma etch to generate a nano-columned Polyethylenedioxythiophene (PEDOT) thin film. 200 nm silicon oxide coated wafers with embedded platinum electrodes are used as a substrate for both fabrication methods. The biggest advantage of this first method is that it is simple, requires a single-step, i.e., synthesizing and positioning procedures are carried out simultaneously. The second method is potentially manufacturable and economic yet environmentally safe. These two methods do not produce extra nano-building materials to discard or create a health hazard. Both PANI nanowires and nano-columned PEDOT films have been tested for humidity detection using a system designed and built for this research to monitor response (current changes) to moisture, To explain the surface to volume ratio effect, 200 nm PANI nanowires and 10 microm PANI wires were directly compared for detecting moisture, and it was shown that the PANI nanowire had a better sensitivity. It was found difficult to monitor the behaviors of the PEDOT reaction to varying

  17. Nano-yarn carbon nanotube fiber based enzymatic glucose biosensor

    NASA Astrophysics Data System (ADS)

    Zhu, Zhigang; Song, Wenhui; Burugapalli, Krishna; Moussy, Francis; Li, Ya-Li; Zhong, Xiao-Hua

    2010-04-01

    A novel brush-like electrode based on carbon nanotube (CNT) nano-yarn fiber has been designed for electrochemical biosensor applications and its efficacy as an enzymatic glucose biosensor demonstrated. The CNT nano-yarn fiber was spun directly from a chemical-vapor-deposition (CVD) gas flow reaction using a mixture of ethanol and acetone as the carbon source and an iron nano-catalyst. The fiber, 28 µm in diameter, was made of bundles of double walled CNTs (DWNTs) concentrically compacted into multiple layers forming a nano-porous network structure. Cyclic voltammetry study revealed a superior electrocatalytic activity for CNT fiber compared to the traditional Pt-Ir coil electrode. The electrode end tip of the CNT fiber was freeze-fractured to obtain a unique brush-like nano-structure resembling a scale-down electrical 'flex', where glucose oxidase (GOx) enzyme was immobilized using glutaraldehyde crosslinking in the presence of bovine serum albumin (BSA). An outer epoxy-polyurethane (EPU) layer was used as semi-permeable membrane. The sensor function was tested against a standard reference electrode. The sensitivities, linear detection range and linearity for detecting glucose for the miniature CNT fiber electrode were better than that reported for a Pt-Ir coil electrode. Thermal annealing of the CNT fiber at 250 °C for 30 min prior to fabrication of the sensor resulted in a 7.5 fold increase in glucose sensitivity. The as-spun CNT fiber based glucose biosensor was shown to be stable for up to 70 days. In addition, gold coating of the electrode connecting end of the CNT fiber resulted in extending the glucose detection limit to 25 µM. To conclude, superior efficiency of CNT fiber for glucose biosensing was demonstrated compared to a traditional Pt-Ir sensor.

  18. Linear and ultrafast nonlinear plasmonics of single nano-objects

    NASA Astrophysics Data System (ADS)

    Crut, Aurélien; Maioli, Paolo; Vallée, Fabrice; Del Fatti, Natalia

    2017-03-01

    Single-particle optical investigations have greatly improved our understanding of the fundamental properties of nano-objects, avoiding the spurious inhomogeneous effects that affect ensemble experiments. Correlation with high-resolution imaging techniques providing morphological information (e.g. electron microscopy) allows a quantitative interpretation of the optical measurements by means of analytical models and numerical simulations. In this topical review, we first briefly recall the principles underlying some of the most commonly used single-particle optical techniques: near-field, dark-field, spatial modulation and photothermal microscopies/spectroscopies. We then focus on the quantitative investigation of the surface plasmon resonance (SPR) of metallic nano-objects using linear and ultrafast optical techniques. While measured SPR positions and spectral areas are found in good agreement with predictions based on Maxwell’s equations, SPR widths are strongly influenced by quantum confinement (or, from a classical standpoint, surface-induced electron scattering) and, for small nano-objects, cannot be reproduced using the dielectric functions of bulk materials. Linear measurements on single nano-objects (silver nanospheres and gold nanorods) allow a quantification of the size and geometry dependences of these effects in confined metals. Addressing the ultrafast response of an individual nano-object is also a powerful tool to elucidate the physical mechanisms at the origin of their optical nonlinearities, and their electronic, vibrational and thermal relaxation processes. Experimental investigations of the dynamical response of gold nanorods are shown to be quantitatively modeled in terms of modifications of the metal dielectric function enhanced by plasmonic effects. Ultrafast spectroscopy can also be exploited to unveil hidden physical properties of more complex nanosystems. In this context, two-color femtosecond pump–probe experiments performed on

  19. Linear and ultrafast nonlinear plasmonics of single nano-objects.

    PubMed

    Crut, Aurélien; Maioli, Paolo; Vallée, Fabrice; Del Fatti, Natalia

    2017-03-29

    Single-particle optical investigations have greatly improved our understanding of the fundamental properties of nano-objects, avoiding the spurious inhomogeneous effects that affect ensemble experiments. Correlation with high-resolution imaging techniques providing morphological information (e.g. electron microscopy) allows a quantitative interpretation of the optical measurements by means of analytical models and numerical simulations. In this topical review, we first briefly recall the principles underlying some of the most commonly used single-particle optical techniques: near-field, dark-field, spatial modulation and photothermal microscopies/spectroscopies. We then focus on the quantitative investigation of the surface plasmon resonance (SPR) of metallic nano-objects using linear and ultrafast optical techniques. While measured SPR positions and spectral areas are found in good agreement with predictions based on Maxwell's equations, SPR widths are strongly influenced by quantum confinement (or, from a classical standpoint, surface-induced electron scattering) and, for small nano-objects, cannot be reproduced using the dielectric functions of bulk materials. Linear measurements on single nano-objects (silver nanospheres and gold nanorods) allow a quantification of the size and geometry dependences of these effects in confined metals. Addressing the ultrafast response of an individual nano-object is also a powerful tool to elucidate the physical mechanisms at the origin of their optical nonlinearities, and their electronic, vibrational and thermal relaxation processes. Experimental investigations of the dynamical response of gold nanorods are shown to be quantitatively modeled in terms of modifications of the metal dielectric function enhanced by plasmonic effects. Ultrafast spectroscopy can also be exploited to unveil hidden physical properties of more complex nanosystems. In this context, two-color femtosecond pump-probe experiments performed on individual

  20. A very small astrometry satellite mission: Nano-JASMINE .

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yukiyasu; Gouda, Naoteru; Tsujimoto, Takuji; Yano, Taihei; Suganuma, Masahiro; Yamauchi, Masahiro; Takato, Naruhisa; Miyazaki, Satoshi; Yamada, Yoshiyuki; Sako, Nobutada; Nakasuka, Shin'ichi

    The current status of the nano-JASMINE project is presented. Nano-JASMINE-a very small satellite weighing less than 10 kg-aims to carry out astrometry measurements of nearby bright stars. This satellite adopts the same observation technique that was used by the HIPPARCOS satellite. In this technique, simultaneous measurements in two different fields of view separated by an angle that is greater than 90 degrees are carried out; these measurements are performed in the course of continuous scanning observations of the entire sky. This technique enables us to distinguish between an irregularity in the spin velocity and the distribution of stellar positions. There is a major technical difference between the nano-JASMINE and the HIPPARCOS satellites-the utilization of a CCD sensor in nano-JASMINE that makes it possible to achieve an astrometry accuracy comparable to that achieved by HIPPARCOS by using an extremely small telescope. We have developed a prototype of the observation system and evaluated its performance. The telescope (5cm) including a beam combiner composed entirely of aluminum. The telescope is based on the standard Ritchey-Chretien optical system and has a composite f-ratio of 33 that enables the matching of the Airy disk size to three times the CCD pixel size of 15um. A full depletion CCD will be used in the time delay integration (TDI) mode in order to efficiently survey the whole sky in wavelengths including the near infrared. The nano-JASMINE satellite is being developed as a piggyback system and is scheduled for launch in 2008. We expect the satellite to measure the position and proper motion of bright stars (mz < 8.3) with an accuracy of 1 mas, this is comparable to the accuracy achieved with the HIPPARCOS satellite.

  1. A very small astrometry satellite mission: Nano-JASMINE

    NASA Astrophysics Data System (ADS)

    Kobayashi, Y.; Gouda, G.; Tsujimoto, T.; Yano, T.; Suganuma, M.; Yamauchi, M.; Takato, N.; Miyazaki, S.; Yamada, Y.; Sako, N.; Nakasuka, S.

    2006-08-01

    The current status of the nano-JASMINE project is presented. Nano-JASMINE--a very small satellite weighing less than 10 kg--aims to carry out astrometry measurements of nearby bright stars. This satellite adopts the same observation technique that was used by the HIPPARCOS satellite. In this technique, simultaneous measurements in two different fields of view separated by an angle that is greater than 90 degrees are carried out; these measurements are performed in the course of continuous scanning observations of the entire sky. This technique enables us to distinguish between an irregularity in the spin velocity and the distribution of stellar positions. There is a major technical difference between the nano-JASMINE and the HIPPARCOS satellites--the utilization of a CCD sensor in nano-JASMINE that makes it possible to achieve an astrometry accuracy comparable to that achieved by HIPPARCOS by using an extremely small telescope. We developed a prototype of the observation system and evaluated its performance. The telescope (5cm) including a beam combiner composed entirely of aluminum. The telescope is based on the standard Ritchey-Chretien optical system and has a composite f-ratio of 33 that enables the matching of the Airy disk size to three times the CCD pixel size of 15um. A full depletion CCD will be used in the time delay integration (TDI) mode in order to efficiently survey the whole sky in wavelengths including the near infrared. The nano-JASMINE satellite is being developed as a piggyback system and is [S: scheduled for launch in 2008. We expect the satellite to measure the position and proper motion of bright stars (mz< 8.3) with an accuracy of 1 mas, this is comparable to the accuracy achieved with the HIPPARCOS satellite.

  2. Nano-JASMINE: a 10-kilogram satellite for space astrometry

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yukiyasu; Gouda, Naoteru; Tsujimoto, Takuji; Yano, Taihei; Suganuma, Masahiro; Yamauchi, Masahiro; Takato, Naruhisa; Miyazaki, Satoshi; Yamada, Yoshiyuki; Sako, Nobutada; Nakasuka, Shin'ichi

    2006-06-01

    The current status of the nano-JASMINE project is presented. Nano-JASMINE - a very small satellite weighing less than 10 kg - aims to carry out astrometry measurements of nearby bright stars. This satellite adopts the same observation technique that was used by the HIPPARCOS satellite. In this technique, simultaneous measurements in two different fields of view separated by an angle that is greater than 90° are carried out; these measurements are performed in the course of continuous scanning observations of the entire sky. This technique enables us to distinguish between an irregularity in the spin velocity and the distribution of stellar positions. There is a major technical difference between the nano-JASMINE and the HIPPARCOS satellites-the utilization of a CCD sensor in nano-JASMINE that makes it possible to achieve an astrometry accuracy comparable to that achieved by HIPPARCOS by using an extremely small telescope. We developed a prototype of the observation system and evaluated its performance. The telescope (5cm) including a beam combiner composed entirely of aluminum. The telescope is based on the standard Ritchey- Chretien optical system and has a composite f-ratio of 33 that enables the matching of the Airy disk size to three times the CCD pixel size of 15μm. A full depletion CCD will be used in the time delay integration (TDI) mode in order to efficiently survey the whole sky in wavelengths including the near infrared. The nano-JASMINE satellite is being developed as a piggyback system and is hoped for launch in 2008. We expect the satellite to measure the position and proper motion of bright stars (m z < 8.3) with an accuracy of 1 mas, this is comparable to the accuracy achieved with the HIPPARCOS satellite.

  3. Nano-yarn carbon nanotube fiber based enzymatic glucose biosensor.

    PubMed

    Zhu, Zhigang; Song, Wenhui; Burugapalli, Krishna; Moussy, Francis; Li, Ya-Li; Zhong, Xiao-Hua

    2010-04-23

    A novel brush-like electrode based on carbon nanotube (CNT) nano-yarn fiber has been designed for electrochemical biosensor applications and its efficacy as an enzymatic glucose biosensor demonstrated. The CNT nano-yarn fiber was spun directly from a chemical-vapor-deposition (CVD) gas flow reaction using a mixture of ethanol and acetone as the carbon source and an iron nano-catalyst. The fiber, 28 microm in diameter, was made of bundles of double walled CNTs (DWNTs) concentrically compacted into multiple layers forming a nano-porous network structure. Cyclic voltammetry study revealed a superior electrocatalytic activity for CNT fiber compared to the traditional Pt-Ir coil electrode. The electrode end tip of the CNT fiber was freeze-fractured to obtain a unique brush-like nano-structure resembling a scale-down electrical 'flex', where glucose oxidase (GOx) enzyme was immobilized using glutaraldehyde crosslinking in the presence of bovine serum albumin (BSA). An outer epoxy-polyurethane (EPU) layer was used as semi-permeable membrane. The sensor function was tested against a standard reference electrode. The sensitivities, linear detection range and linearity for detecting glucose for the miniature CNT fiber electrode were better than that reported for a Pt-Ir coil electrode. Thermal annealing of the CNT fiber at 250 degrees C for 30 min prior to fabrication of the sensor resulted in a 7.5 fold increase in glucose sensitivity. The as-spun CNT fiber based glucose biosensor was shown to be stable for up to 70 days. In addition, gold coating of the electrode connecting end of the CNT fiber resulted in extending the glucose detection limit to 25 microM. To conclude, superior efficiency of CNT fiber for glucose biosensing was demonstrated compared to a traditional Pt-Ir sensor.

  4. Heat dissipation from carbon nano-electronics

    NASA Astrophysics Data System (ADS)

    Ong, Zhun Yong

    2011-12-01

    The incorporation of graphitic compounds such as carbon nanotubes (CNTs) and graphene into nano-electronic device packaging holds much promise for waste heat management given their high thermal conductivities. However, as these graphitic materials must be used in together with other semiconductor/insulator materials, it is not known how thermal transport is affected by the interaction. Using different simulation techniques, in this thesis, we evaluate the thermal transport properties --- thermal boundary conductance (TBC) and thermal conductivity --- of CNTs and single-layer graphene in contact with an amorphous SiO2 (a-SiO2) substrate. First, the theoretical methodologies and concepts used in our simulations are presented. In particular, two concepts are described in detail as they are necessary for the understanding of the subsequent chapters. The first is the linear response Green-Kubo (GK) theory of thermal boundary conductance (TBC), which we develop in this thesis, and the second is the spectral energy density method, which we use to directly compute the phonon lifetimes and thermal transport coefficients. After we set the conceptual foundations, the TBC of the CNT-SiO 2 interface is computed using non-equilibrium molecular dynamics (MD) simulations and the new Green-Kubo method that we have developed. Its dependence on temperature, the strength of the interaction with the substrate, and tube diameter are evaluated. To gain further insight into the phonon dynamics in supported CNTs, the scattering rates are computed using the spectral energy density (SED) method. With this method, we are able to distinguish the different scattering mechanisms (boundary and CNT-substrate phonon-phonon) and rates. The phonon lifetimes in supported CNTs are found to be reduced by contact with the substrate and we use that lifetime reduction to determine the change in CNT thermal conductivity. Next, we examine thermal transport in graphene supported on SiO 2. The phonon

  5. Photonic Interrogation and Control of Nano Processes

    NASA Technical Reports Server (NTRS)

    Jassemnejad, Baha

    2003-01-01

    My research activities for the summer of 2003 consisted of two projects: One project was concerned with determining a method for predicting the static and dynamic assembly properties of nano-structures using laser tweezers. The other project was to investigate the generation of Laguerre-Gaussian modes using a spatial light modulator incorporated into an optical tweezers system. Concerning the first project, I initially pursued the approach suggested by my NASA colleague Dr. Art Decker. This approach involved mimicking the model of the structure of atomic nucleus for the assembly of 1 to 100 atoms using allowed quadruple transitions induced by orbital angular momentums of a Laguerre- Gaussian (Doughnut) laser mode. After realizing the inaptness of the nuclear model with the nanostructure model as far as the binding forces and transitions were concerned, I focused on using quantum dot modei. This model was not attuned also for the host lattice influences the electronic structure of the quantum dot. Thus one other option that I decided to pursue was the approach of molecular quantum mechanics. In this approach the nanostructure is treated as a large (10-100 nm) molecule constructed from single element or multi-elements. Subsequent to consultation with Dr. Fred Morales, a chemical engineer at NASA GRC, and Dr. David Ball, a computational chemist at Cleveland State University, I acquired a molecular-quantum computation software, Hyperchem 7.0. This software allows simulation of different molecular structures as far as their static and dynamic behaviors are concerned. The time that I spent on this project was about eight weeks. Once this suitable approach was identified, I realized the need to collaborate with a computational quantum chemist to pursue searching for stable nanostructures in the range of 10-100 nm that we can be assembled using laser tweezers. The second project was about generating laser tweezers that possess orbital angular momentum. As shown, we were

  6. Synthesis of branched, nano channeled, ultrafine and nano carbon tubes from PET wastes using the arc discharge method

    SciTech Connect

    Joseph Berkmans, A.; Jagannatham, M.; Priyanka, S.; Haridoss, Prathap

    2014-11-15

    Highlights: • Polymer wastes are converted into ultrafine and nano carbon tubes and spheres. • Simple process with a minimal processing time. • It is a catalyst free and solvent free approach. • This process forms branched ultrafine carbon tubules with nano channels. - Abstract: Upcycling polymer wastes into useful, and valuable carbon based materials, is a challenging process. We report a novel catalyst-free and solvent-free technique for the formation of nano channeled ultrafine carbon tubes (NCUFCTs) and multiwalled carbon nanotubes (MWCNTs) from polyethylene terephthalate (PET) wastes, using rotating cathode arc discharge technique. The soot obtain from the anode contains ultrafine and nano-sized solid carbon spheres (SCS) with a mean diameter of 221 nm and 100 nm, respectively, formed at the lower temperature region of the anode where the temperature is approximately 1700 °C. The carbon spheres are converted into long “Y” type branched and non-branched NCUFCTs and MWCNTs at higher temperature regions where the temperature is approximately 2600 °C, with mean diameters of 364 nm and 95 nm, respectively. Soot deposited on the cathode is composed of MWCNTs with a mean diameter of 20 nm and other nanoparticles. The tubular structures present in the anode are longer, bent and often coiled with lesser graphitization compared to the nanotubes in the soot on the cathode.

  7. Single-layer nano-carbon film, diamond film, and diamond/nano-carbon composite film field emission performance comparison

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoping; Wang, Jinye; Wang, Lijun

    2016-05-01

    A series of single-layer nano-carbon (SNC) films, diamond films, and diamond/nano-carbon (D/NC) composite films have been prepared on the highly doped silicon substrate by using microwave plasma chemical vapor deposition techniques. The films were characterised by scanning electron microscopy, Raman spectroscopy, and field emission I-V measurements. The experimental results indicated that the field emission maximum current density of D/NC composite films is 11.8-17.8 times that of diamond films. And the field emission current density of D/NC composite films is 2.9-5 times that of SNC films at an electric field of 3.0 V/μm. At the same time, the D/NC composite film exhibits the advantage of improved reproducibility and long term stability (both of the nano-carbon film within the D/NC composite cathode and the SNC cathode were prepared under the same experimental conditions). And for the D/NC composite sample, a high current density of 10 mA/cm2 at an electric field of 3.0 V/μm was obtained. Diamond layer can effectively improve the field emission characteristics of nano-carbon film. The reason may be due to the diamond film acts as the electron acceleration layer.

  8. Potential Release of Manufactured Nano Objects During Sanding of Nano-Coated Wood Surfaces.

    PubMed

    Fransman, Wouter; Bekker, Cindy; Tromp, Peter; Duis, Willem B

    2016-08-01

    Increasing production and applications of manufactured nano objects (MNOs) have become a source for human exposure and therefore raise concerns and questions about the possible health effects. In this study, the potential release of nano objects, their agglomerates, and aggregates (NOAA) as a result of sanding of hardwood treated with MNOs-containing coating was examined. Two types of MNO-containing coating were compared with untreated hardwood that allowed the evaluation of the influence of the chemical composition on the release of particles. Furthermore, the rotation speed of the sander and the grit size of the sanding paper were varied in order to assess their influence on the release of particles.Measurements were conducted in a gas-tight chamber with a volume of 19.5 m(3) in which ventilation was minimized during experiments. Particle size distributions were assessed by scanning mobility particle sizer , aerodynamic particle sizer, and electrical low pressure impactor. Furthermore, aerosol number concentrations (Nanotracer), active surface area (LQ1), and fractionated mass (Cascade Impactor) were measured before, during, and after sanding. Scanning electron microscope/energy dispersive X-ray (SEM/EDX) analysis was performed to adequately characterize the morphology, size, and chemical composition of released particles.SEM/EDX analysis indicated that sanding surfaces treated with MNO-containing coating did not release the designated MNO as free primary particles. In both coatings, clusters of MNO were perceived embedded in and attached to micro-sized wood and/or coating particles created by sanding the coated surface. Real-time measurements indicated a lower release of micro-sized particles from sanding of surfaces treated with Coating I than from sanding untreated surfaces or surfaces treated with Coating II. A substantial increase in nanosized and a slight increase in micro-sized particles was perceived as the rotation speed of the sander increased. However

  9. Bio-Based Nano Composites from Plant Oil and Nano Clay

    NASA Astrophysics Data System (ADS)

    Lu, Jue; Hong, Chang K.; Wool, Richard P.

    2003-03-01

    We explored the combination of nanoclay with new chemically functionalized, amphiphilic, plant oil resins to form bio-based nanocomposites with improved physical and mechanical properties. These can be used in many new applications, including the development of self-healing nanocomposites through controlled reversible exfoliation/intercalation, and self-assembled nano-structures. Several chemically modified triglyceride monomers of varying polarity, combined with styrene (ca 30include acrylated epoxidized soybean oil (AESO), maleated acrylated epoxidized soybean oil (MAESO) and soybean oil pentaerythritol glyceride maleates (SOPERMA), containing either hydroxyl group or acid functionality or both. The clay used is a natural montmorillonite modified with methyl tallow bis-2-hydroxyethyl quaternary ammonium chloride, which has hydroxyl groups. Both XRD and TEM showed a completely exfoliated structure at 3 wtwhen the clay content is above 5 wtconsidered a mix of intercalated and partially exfoliated structure. The controlled polarity of the monomer has a major effect on the reversible dispersion of clay in the polymer matrix. The bio-based nanocomposites showed a significant increase in flexural modulus and strength. Supported by EPA and DoE

  10. Field Testing of Nano-PCM Enhanced Building Envelope Components

    SciTech Connect

    Biswas, Kaushik; Childs, Phillip W; Atchley, Jerald Allen

    2013-08-01

    The U.S. Department of Energy s (DOE) Building Technologies Program s goal of developing high-performance, energy efficient buildings will require more cost-effective, durable, energy efficient building envelopes. Forty-eight percent of the residential end-use energy consumption is spent on space heating and air conditioning. Reducing envelope-generated heating and cooling loads through application of phase change material (PCM)-enhanced envelope components can facilitate maximizing the energy efficiency of buildings. Field-testing of prototype envelope components is an important step in estimating their energy benefits. An innovative phase change material (nano-PCM) was developed with PCM encapsulated with expanded graphite (interconnected) nanosheets, which is highly conducive for enhanced thermal storage and energy distribution, and is shape-stable for convenient incorporation into lightweight building components. During 2012, two test walls with cellulose cavity insulation and prototype PCM-enhanced interior wallboards were installed in a natural exposure test (NET) facility at Charleston, SC. The first test wall was divided into four sections, which were separated by wood studs and thin layers of foam insulation. Two sections contained nano-PCM-enhanced wallboards: one was a three-layer structure, in which nano-PCM was sandwiched between two gypsum boards, and the other one had PCM dispersed homogeneously throughout graphite nanosheets-enhanced gypsum board. The second test wall also contained two sections with interior PCM wallboards; one contained nano-PCM dispersed homogeneously in gypsum and the other was gypsum board containing a commercial microencapsulated PCM (MEPCM) for comparison. Each test wall contained a section covered with gypsum board on the interior side, which served as control or a baseline for evaluation of the PCM wallboards. The walls were instrumented with arrays of thermocouples and heat flux transducers. Further, numerical modeling of

  11. The heat resistance of a polyurethane coating filled with modified nano-CaCO3

    NASA Astrophysics Data System (ADS)

    Li, Bin; Li, Song-Mei; Liu, Jian-Hua; Yu, Mei

    2014-10-01

    The modification of polyurethane coating by adding surface-modified CaCO3 nanoparticles (nano-CaCO3) was investigated in this paper. To improve interfacial interaction between the nano-CaCO3 and the polyurethane (PU) matrix, a silane coupling agent (KH560) was used to modify the nano-CaCO3. The grafting of KH560 on the nano-CaCO3 surfaces was characterized by the TEM, FTIR and TGA techniques. The modification of the nano-CaCO3 surfaces with KH560 was demonstrated to improve the dispersity of nano-CaCO3. FTIR, SEM and AFM were used to characterize the polyurethane coating. The FTIR spectrum indicated that the modification of nano-CaCO3 does not influence the chemical structure of the PU matrix. The roughness and gloss of the nanocomposite coatings containing various amount of nano-CaCO3 were evaluated using a roughness tester and a brightness meter. The heat resistance of the polyurethane coating containing various amounts of nano-CaCO3 was evaluated using the TGA technique. The results revealed that nano-CaCO3 treatment with KH560 improves the nanoparticle dispersion and heat-resistance of polyurethane coating.

  12. Comparison of short-term toxicity between Nano-Se and selenite in mice.

    PubMed

    Zhang, Jinsong; Wang, Huali; Yan, Xiangxue; Zhang, Lide

    2005-01-21

    We previously reported that, as compared with selenite, nano red elemental selenium (Nano-Se) had lower acute toxicity in mice and similar bioavailability in terms of up-regulating seleno-enzymes. The short-term toxicity of both selenite and Nano-Se in mice was further compared in this study. At an oral dose of 6 mg/kg bw per day administered for consecutive 12 days, selenite and Nano-Se completely and partially suppressed mice growth respectively. Abnormal liver function was more pronounced with selenite treatment than Nano-Se as indicated by the increase of both alanine aminotransferase and aspartate aminotransferase in serum. Selenite inhibited liver catalase and superoxide dismutase activities, whereas, Nano-Se did not affect these two antioxidant enzymes. Selenite increased the malondialdehyde content of liver, but Nano-Se decreased it. Both Se forms had similar effects on depletion of reduced glutathione and up-regulated glutathione peroxidase. Nano-Se was more potent than selenite in the induction of glutathione S-transferase. At oral doses of 2 or 4 mg/kg bw per day for consecutive 15 days, selenite was more active than Nano-Se in supressing growth, deleting reduced glutathione, and inhibiting superoxide dismutase activities. Taken together, these results indicate that over a short-term, a high-dose of selenite caused more pronounced oxidative stress, greater liver injury, and prominent retardation of growth as compared to Nano-Se.

  13. Kinetic study on removal of copper(II) using goethite and hematite nano-photocatalysts.

    PubMed

    Chen, Yen-Hua; Li, Fu-An

    2010-07-15

    Goethite and hematite nanomaterials (nano-goethite and nano-hematite) can be synthesized using a coprecipitation method. Nano-hematite is synthesized via the reaction of HCl and FeCl(3) solution at 100 degrees C for 2 days, while nano-goethite is prepared by adding Fe(2)(SO(4))(3) into the 2.5 M NaOH solution for 4h, and then heated at 40 degrees C for 2 days. Afterward the photocatalytic decomposition of methylene blue solution is performed by UV-light irradiation, and the adsorption procedure is carried out by batch experiments. It is observed that both nano-hematite and nano-goethite exhibit some photocatalytic activity and possess a high adsorption capacity for copper ions. The maximum Cu(II) adsorption capacity is 149.25 and 84.46 mg/g for nano-goethite and nano-hematite, respectively. Further, the experimental data are well fitted to the pseudo-second-order equation. It also suggests that the Langmuir isotherm is more adequate than the Freundlich isotherm in simulating the adsorption isotherm of Cu(2+), and the Cu(2+) adsorption onto nanomaterials is a spontaneous process. Therefore, these findings indicate that nano-goethite and nano-hematite are effective materials for Cu(2+) removal and, together with its photocatalytic activity, may be applied in the removal of heavy metal ions from aqueous streams.

  14. Construction of micro-nano network structure on titanium surface for improving bioactivity

    NASA Astrophysics Data System (ADS)

    Jiang, Pinliang; Liang, Jianhe; Lin, Changjian

    2013-09-01

    A novel hierarchical micro-nano structured titania layer was constructed on Ti surface to mimic the multi-level bone structure. The Ti substrate was subjected to a suitable acid etching and subsequent anodization in NaOH electrolyte to form a micro-nano porous titania layer. It was indicated that this microporous/nano-network (micro/nano-network) structured surface presented the enhanced wettability and superhydrophilic property. The polarization curve measurements showed that the as-prepared micro/nano-network structured TiO2 surface was of better corrosion resistance compared to the blank Ti surface, according to its corrosion current decreased, corrosion potential shifted positively and polarization resistance increased in Hank's solution. Meanwhile, the Mott-Schottky plots revealed that less oxygen vacancies existed in the micro/nano-network structured TiO2 film in contrast to the natural oxide film on blank Ti surface. Moreover, it was observed that the micro/nano-network structured surface was completely covered by a homogeneous apatite layer when immersed in simulated body fluid (SBF) for 14 days, exhibiting an excellent ability of biomineration. Furthermore, the superior cell adhesion and viability were discerned on such hierarchically structured surface, through a comparison of MG63 cell behaviors on blank Ti surface, nano-network structured surface and micro/nano-network structured surface. All results suggest our construction of micro-nano porous TiO2 surface is a promising strategy for improving the bioactivity of titanium implants.

  15. Preparation of hybrid nano biocomposite κ-carrageenan/cellulose nanocrystal/nanoclay

    NASA Astrophysics Data System (ADS)

    Zakuwan, Siti Zarina; Ahmad, Ishak; Ramli, Nazaruddin

    2013-11-01

    Biodegradable composites film based on κ-carrageenan and nano particles as filler was prepared to study the mechanical strength of carrageenan composites. Solution casting technique was used to prepare_this biocomposite. Preparation of composite film and nano filler involve two stages, preparation of cellulose nanocrystals (CNC) from kenaf with alkali treatment, bleaching, and hydrolysis followed by the preparation of two types of nano composite. Tensile test was carried on the composite film based on κ-carrageenan with the variation percentage of CNC and nano clay to obtain the optimum CNC and nano clay loading. After that hybrid nano-biocomposite film based on κ-carrageenan with the variation percentage of CNC/nano clay (OMMT) according to optimum value of composite carrageenan/CNC and composite carrageenan/nano clay film was prepared. The effect of nano filler on the mechanical properties of carrageenan films was examined. κ-carrageenan biocomposite increased with the optimum at 4% CNC and nano clay composition. Additional improvement of tensile strength with hybridization of CNC and nanoclay indicated better mechanical properties.

  16. Single-walled carbon nanotubes as nano-electrode and nano-reactor to control the pathways of a redox reaction.

    PubMed

    McSweeney, Robert L; Chamberlain, Thomas W; Davies, E Stephen; Khlobystov, Andrei N

    2014-11-28

    Single-walled carbon nanotubes have been demonstrated as effective nanoscale containers for a redox active organometallic complex Cp(Me)Mn(CO)3, acting simultaneously as nano-electrode and nano-reactor. Extreme spatial confinement of the redox reaction within the nanotubes changes its pathway compared to bulk solution due to stabilisation of a reactive intermediate.

  17. Nano silver and nano zinc-oxide in surface waters – Exposure estimation for Europe at high spatial and temporal resolution

    PubMed Central

    Dumont, Egon; Johnson, Andrew C.; Keller, Virginie D.J.; Williams, Richard J.

    2015-01-01

    Nano silver and nano zinc-oxide monthly concentrations in surface waters across Europe were modeled at ∼6 × 9 km spatial resolution. Nano-particle loadings from households to rivers were simulated considering household connectivity to sewerage, sewage treatment efficiency, the spatial distribution of sewage treatment plants, and their associated populations. These loadings were used to model temporally varying nano-particle concentrations in rivers, lakes and wetlands by considering dilution, downstream transport, water evaporation, water abstraction, and nano-particle sedimentation. Temporal variability in concentrations caused by weather variation was simulated using monthly weather data for a representative 31-year period. Modeled concentrations represent current levels of nano-particle production. Two scenarios were modeled. In the most likely scenario, half the river stretches had long-term average concentrations exceeding 0.002 ng L−1 nano silver and 1.5 ng L−1 nano zinc oxide. In 10% of the river stretches, these concentrations exceeded 0.18 ng L−1 and 150 ng L−1, respectively. Predicted concentrations were usually highest in July. PMID:25463731

  18. Minimum ignition temperature of nano and micro Ti powder clouds in the presence of inert nano TiO2 powder.

    PubMed

    Yuan, Chunmiao; Amyotte, Paul R; Hossain, Md Nur; Li, Chang

    2014-06-30

    Minimum ignition temperature (MIT) of micro Ti powder increased gradually with increases in nano-sized TiO2 employed as an inertant. Solid TiO2 inertant significantly reduced ignition hazard of micro Ti powder in contact with hot surfaces. The MIT of nano Ti powder remained low (583 K), however, even with 90% TiO2. The MIT of micro Ti powder, when mixed with nano Ti powder at concentrations as low as 10%, decreased so dramatically that its application as a solid fuel may be possible. A simple MIT model was proposed for aggregate particle size estimation and better understanding of the inerting effect of nano TiO2 on MIT. Estimated particle size was 1.46-1.51 μm larger than that in the 20-L sphere due to poor dispersion in the BAM oven. Calculated MITs were lower than corresponding empirically determined values for micro Ti powder because nano-sized TiO2 coated the micro Ti powder, thereby decreasing its reaction kinetics. In the case of nano Ti powder, nano-sized TiO2 facilitated dispersion of nano Ti powder which resulted in a calculated MIT that was greater than the experimentally determined value.

  19. Evaluation of the Mechanical Properties of Multi-nano Layered Copper-Nickel Thin Film by the Dynamic-Nano Indentation Method

    NASA Astrophysics Data System (ADS)

    Choi, Yong

    2016-11-01

    The dynamic nano-indentation method was applied to study the effect of interface moving behavior with heat treatment on the nano-mechanical properties of multi-nano-layered copper-nickel thin film. Layer-by-layer depositions of copper and nickel of nano-sized thickness were prepared by two-step pulse electro-deposition in a modified copper-nickel sulfate bath at 25°C. The multi-layered copper-nickel thin sheet was composed of a 20-nm-thick copper-rich nickel phase, and a 25-nm-thick nickel-rich copper phase. Thermal vacuum annealing influenced the interface morphology between copper and nickel nano-layers. Inter-diffusion mainly occurred after annealing at 500°C for 6 h. The interface disappeared after annealing at 600°C to form a completely solid solution. Thermal annealing reduced the nano-hardness and elastic recovery. The average nano-hardness of the multi-layered nano-copper-nickel thin film for the specimens of as-received, 300°C, 500°C and 600°C were 7.9 Gpa, 6.1 Gpa, 4.7 Gpa and 3.0 GPa, respectively. The elastic stiffness was 15.77 × 104 Nm-1 for the as-received specimen, which finally became 2.98 × 104 Nm-1 for the specimen after annealing at 600°C for 6 h.

  20. Preparation of silver nano-particles immobilized onto chitin nano-crystals and their application to cellulose paper for imparting antimicrobial activity.

    PubMed

    Li, Zhihan; Zhang, Ming; Cheng, Dong; Yang, Rendang

    2016-10-20

    Immobilized silver nano-particles (Ag NPs) possess excellent antimicrobial properties due to their unique surface characteristics. In this paper, immobilized silver nano-particles were synthesized in the presence of chitin nano-crystals (CNC) based on the Tollens mechanism (reduction of silver ion by aldehydes in the chitosan oligosaccharides (COS)) under microwave-assisted conditions. The prepared Ag NPs-loaded CNC nano-composites were then applied onto the paper surface via coating for the preparation of antibacterial paper. Fourier transform infrared (FT-IR) and X-ray diffraction (XRD) results confirmed that the Ag NPs were immobilized onto the CNC. The transmission electron microscope (TEM) and scanning electron microscopy (SEM) results further revealed that the spherical Ag NPs (5-12nm) were well dispersed on the surface of CNC. The coated paper made from the Ag NPs-loaded CNC nano-composites exhibited a high effectiveness of the antibacterial activity against E. coli or S. aureus.

  1. Mirror profile optimization for nano-focusing KB mirror

    SciTech Connect

    Zhang Lin; Baker, Robert; Barrett, Ray; Cloetens, Peter; Dabin, Yves

    2010-06-23

    A KB focusing mirror width profile has been optimized to achieve nano-focusing for the nano-imaging end-station ID22NI at the ESRF. The complete mirror and flexure bender assembly has been modeled in 3D with finite element analysis using ANSYS. Bender stiffness, anticlastic effects and geometrical non-linear effects have been considered. Various points have been studied: anisotropy and crystal orientation, stress in the mirror and bender, actuator resolution and the mirror-bender adhesive bonding... Extremely high performance of the mirror is expected with residual slope error smaller than 0.6 {mu}rad, peak-to-valley, compared to the bent slope of 3000 {mu}rad.

  2. Nano-materials enabled thermoelectricity from window glasses.

    PubMed

    Inayat, Salman B; Rader, Kelly R; Hussain, Muhammad M

    2012-01-01

    With a projection of nearly doubling up the world population by 2050, we need wide variety of renewable and clean energy sources to meet the increased energy demand. Solar energy is considered as the leading promising alternate energy source with the pertinent challenge of off sunshine period and uneven worldwide distribution of usable sun light. Although thermoelectricity is considered as a reasonable renewable energy from wasted heat, its mass scale usage is yet to be developed. Here we show, large scale integration of nano-manufactured pellets of thermoelectric nano-materials, embedded into window glasses to generate thermoelectricity using the temperature difference between hot outside and cool inside. For the first time, this work offers an opportunity to potentially generate 304 watts of usable power from 9 m(2) window at a 20°C temperature gradient. If a natural temperature gradient exists, this can serve as a sustainable energy source for green building technology.

  3. Recent advances in micro- and nano-machining technologies

    NASA Astrophysics Data System (ADS)

    Gao, Shang; Huang, Han

    2016-12-01

    Device miniaturization is an emerging advanced technology in the 21st century. The miniaturization of devices in different fields requires production of micro- and nano-scale components. The features of these components range from the sub-micron to a few hundred microns with high tolerance to many engineering materials. These fields mainly include optics, electronics, medicine, bio-technology, communications, and avionics. This paper reviewed the recent advances in micro- and nano-machining technologies, including micro-cutting, micro-electrical-discharge machining, laser micro-machining, and focused ion beam machining. The four machining technologies were also compared in terms of machining efficiency, workpiece materials being machined, minimum feature size, maximum aspect ratio, and surface finish.

  4. Micro and nano devices in passive millimetre wave imaging systems

    NASA Astrophysics Data System (ADS)

    Appleby, R.

    2013-06-01

    The impact of micro and nano technology on millimetre wave imaging from the post war years to the present day is reviewed. In the 1950s whisker contacted diodes in mixers and vacuum tubes were used to realise both radiometers and radars but required considerable skill to realise the performance needed. Development of planar semiconductor devices such as Gunn and Schottky diodes revolutionised mixer performance and provided considerable improvement. The next major breakthrough was high frequency transistors based on gallium arsenide which were initially used at intermediate frequencies but later after further development at millimeter wave frequencies. More recently Monolithic Microwave Integrated circuits(MMICs) offer exceptional performance and the opportunity for innovative design in passive imaging systems. In the future the use of micro and nano technology will continue to drive system performance and we can expect to see integration of antennae, millimetre wave and sub millimetre wave circuits and signal processing.

  5. Single Wall Carbon Nano Tube Films and Coatings

    NASA Astrophysics Data System (ADS)

    Sreekumar, T. V.; Kumar, Satish; Ericson, Lars M.; Smalley, Richard E.

    2002-03-01

    Purified single wall carbon nano tubes (SWNTs) produced from the high-pressure carbon monoxide (HiPCO) process have been dissolved /dispersed in oleum. These solutions /dispersions were optically homogeneous and have been used to form stand-alone SWNT films. The washed, dried, and heat-treated films are isotropic. The scanning electron micrographs of the film surface shows that the nanotube ropes (or fibrils) of about 20 nm diameters are arranged just like macroscopic fibers in a non-woven fabric. Polarized Raman spectroscopy of the SWNT film confirms the isotropic nature of these films. The films are being characterized for their thermal, mechanical as well electrical properties. Thin nano tube coatings, including optically transparent coatings, have also been made on a variety of substrates such as glass, polyethylene, polystyrene, polypropylene, silicon wafer, as well as stainless steel.

  6. First principles simulations of nano-peptides on copper surfaces

    NASA Astrophysics Data System (ADS)

    Le, Duy; Rahman, Talat S.

    Protein folding is the process in which a protein structure finds its stable conformation or functional shape. It is considered as a robust way for self-assembling proteins into conformations with desired functionalities. In this work, to obtain a microscopic understanding of the protein folding phenomenon, as influenced by a metallic environment, we perform density functional theory based simulations of the folding of a 9-amino-acid nano-peptide on various copper surfaces. We show that the considered nano-peptides fold into stable monomers or dimers with different conformations depending on the crystallographic orientation of the surface. Comparison of our simulated Scanning Tunneling Microscopy (STM) image with available experimental results provides insights into the microscopic forces responsible for dimerization on Cu(100). This work is supported in part by NSF Grant CHE-1310327.

  7. Nano-Composite Material Development for 3-D Printers

    SciTech Connect

    Satches, Michael Randolph

    2015-12-01

    Graphene possesses excellent mechanical properties with a tensile strength that may exceed 130 GPa, excellent electrical conductivity, and good thermal properties. Future nano-composites can leverage many of these material properties in an attempt to build designer materials for a broad range of applications. 3-D printing has also seen vast improvements in recent years that have allowed many companies and individuals to realize rapid prototyping for relatively low capital investment. This research sought to create a graphene reinforced, polymer matrix nano-composite that is viable in commercial 3D printer technology, study the effects of ultra-high loading percentages of graphene in polymer matrices and determine the functional upper limit for loading. Loadings varied from 5 wt. % to 50 wt. % graphene nanopowder loaded in Acrylonitrile Butadiene Styrene (ABS) matrices. Loaded sample were characterized for their mechanical properties using three point bending, tensile tests, as well as dynamic mechanical analysis.

  8. CCD centroiding analysis for Nano-JASMINE observation data

    NASA Astrophysics Data System (ADS)

    Niwa, Yoshito; Yano, Taihei; Araki, Hiroshi; Gouda, Naoteru; Kobayashi, Yukiyasu; Yamada, Yoshiyuki; Tazawa, Seiichi; Hanada, Hideo

    2010-07-01

    Nano-JASMINE is a very small satellite mission for global space astrometry with milli-arcsecond accuracy, which will be launched in 2011. In this mission, centroids of stars in CCD image frames are estimated with sub-pixel accuracy. In order to realize such a high precision centroiding an algorithm utilizing a least square method is employed. One of the advantages is that centroids can be calculated without explicit assumption of the point spread functions of stars. CCD centroiding experiment has been performed to investigate whether this data analysis is available, and centroids of artificial star images on a CCD are determined with a precision of less than 0.001 pixel. This result indicates parallaxes of stars within 300 pc from Sun can be observed in Nano-JASMINE.

  9. Optics for nano-satellite X-ray monitor

    NASA Astrophysics Data System (ADS)

    Tichý, Vladimír.; Burrows, David N.; Prieskorn, Zachary; Hudec, René

    The Schmidt lobster eye design for a grazing incidence X-ray optics provides wide field of view of the order of many degrees, for this reason it can be a convenient approach for the construction of space X-ray monitors. It is possible to assemble Schmidt lobster eye telescopes with dimensions and focal lengths acceptable for nano class satellites. In this paper, draft of nano-class space mission providing monitoring of specific sky area is presented. Preliminary optical design study for such mission is performed. Two of possible opticle designs are presented. For those designs, field of view, effective input area and other basic optical parameters are calculated. Examples of observed images are presented.

  10. Evaporation of sessile droplets on nano-porous alumina surfaces

    NASA Astrophysics Data System (ADS)

    Singh, Sanchit K.; Pratap, Dheeraj; Ramakrishna, S. Anantha; Khanderkar, Sameer

    2013-07-01

    An experimental investigation of evaporation of sessile droplets is presented on nano-porous alumina surfaces with different pore distribution morphologies and pore sizes. Evaporation can be considered as a quasi-steady-state process, such that the vapor concentration distribution above the droplet satisfies the Laplace equation, but with a timevarying droplet surface. For benchmarking, the evaporation of sessile water and ethanol droplets is also investigated on standard borosilicate glass and Teflon surfaces respectively, and results are compared with the previous work. Contact angle variation with time is also recorded and high speed videos showing the spreading process of droplets on nanoporous surfaces are taken. The results clearly show that nano-structuring is an effective tool to control wettability as well as the diffusive evaporation process.

  11. Nano-materials Enabled Thermoelectricity from Window Glasses

    NASA Astrophysics Data System (ADS)

    Inayat, Salman B.; Rader, Kelly R.; Hussain, Muhammad M.

    2012-11-01

    With a projection of nearly doubling up the world population by 2050, we need wide variety of renewable and clean energy sources to meet the increased energy demand. Solar energy is considered as the leading promising alternate energy source with the pertinent challenge of off sunshine period and uneven worldwide distribution of usable sun light. Although thermoelectricity is considered as a reasonable renewable energy from wasted heat, its mass scale usage is yet to be developed. Here we show, large scale integration of nano-manufactured pellets of thermoelectric nano-materials, embedded into window glasses to generate thermoelectricity using the temperature difference between hot outside and cool inside. For the first time, this work offers an opportunity to potentially generate 304 watts of usable power from 9 m2 window at a 20°C temperature gradient. If a natural temperature gradient exists, this can serve as a sustainable energy source for green building technology.

  12. Nano-intercalated organophosphorus-hydrolyzing enzymes in organophosphorus antagonism.

    PubMed

    Petrikovics, Ilona; Wales, Melinda; Budai, Marianna; Yu, Jorn C C; Szilasi, Mária

    2012-03-01

    A dendritic poly(2-alkyloxazoline)-based polymer was studied as a new carrier system for the organophosphorus-hydrolyzing recombinant enzymes, organophosphorus acid anhydrolase and organophosphorus hydrolase. Paraoxon (PO) and diisopropylfluorophosphate (DFP) were used as model organophosphorus compounds. Changes in plasma cholinesterase activity were monitored. The cholinesterase activity was proportional to the concentrations of DFP or PO. Plasma cholinesterase activity was higher in animals receiving enzyme and oxime before the organophosphates than in the oxime-only pretreated groups. These studies suggest that cholinesterase activity can serve as an indicator for the in vivo protection by the nano-intercalated organophosphorus acid anhydrolase or organophosphorus hydrolase against organophosphorus intoxications. These studies represent a practical application of polymeric nano-delivery systems as enzyme carriers in drug antidotal therapy.

  13. Nano-materials Enabled Thermoelectricity from Window Glasses

    PubMed Central

    Inayat, Salman B.; Rader, Kelly R.; Hussain, Muhammad M.

    2012-01-01

    With a projection of nearly doubling up the world population by 2050, we need wide variety of renewable and clean energy sources to meet the increased energy demand. Solar energy is considered as the leading promising alternate energy source with the pertinent challenge of off sunshine period and uneven worldwide distribution of usable sun light. Although thermoelectricity is considered as a reasonable renewable energy from wasted heat, its mass scale usage is yet to be developed. Here we show, large scale integration of nano-manufactured pellets of thermoelectric nano-materials, embedded into window glasses to generate thermoelectricity using the temperature difference between hot outside and cool inside. For the first time, this work offers an opportunity to potentially generate 304 watts of usable power from 9 m2 window at a 20°C temperature gradient. If a natural temperature gradient exists, this can serve as a sustainable energy source for green building technology. PMID:23150789

  14. Studies on structural properties of clay magnesium ferrite nano composite

    NASA Astrophysics Data System (ADS)

    Kaur, Manpreet; Singh, Mandeep; Jeet, Kiran; Kaur, Rajdeep

    2015-08-01

    Magnesium ferrite-bentonite clay composite was prepared by sol-gel combustion method employing citric acid as complexing agent and fuel. The effect of clay on the structural properties was studied with X-ray diffraction (XRD), Fourier transform infrared (FT-IR) Spectroscopy, Scanning electron microscopy (SEM), SEM- Energy dispersive Spectroscope (EDS) and BET surface area analyzer. Decrease in particle size and density was observed on addition of bentonite clay. The BET surface area of nano composite containing just 5 percent clay was 74.86 m2/g. Whereas porosity increased from 40.5 per cent for the pure magnesium ferrite to 81.0 percent in the composite showing that nano-composite has potential application as an adsorbent.

  15. Electrical properties of epoxy resin based nano-composites

    NASA Astrophysics Data System (ADS)

    Tuncer, Enis; Sauers, Isidor; James, D. Randy; Ellis, Alvin R.; Parans Paranthaman, M.; Aytug, Tolga; Sathyamurthy, Srivatsan; More, Karren L.; Li, Jing; Goyal, Amit

    2007-01-01

    We investigate the electrical properties of composite materials prepared as nano- and sub-micron-scale metal-oxide particles embedded in a commercial resin. The filler particles are barium titanate and calcium copper titanate. The physical and structural characteristics of the constituents and the fabricated composites are reported. Electrical characterization of the composite samples is performed using time- and frequency-domain dielectric spectroscopy techniques. The electrical breakdown strength of samples with nano- and sub-micron-sized particles have better electrical insulation properties than the unfilled resin. The start-up funding for the research was provided by the US Department of Energy, Office of Electricity Delivery and Energy Reliability, and follow-on funding was continued by the Laboratory Directed Research and Development (LDRD) Program of Oak Ridge National Laboratory (ORNL), managed by UT-Battelle, LLC for the US Department of Energy under Contract No. DE-AC05-00OR22725 (D06-100).

  16. Field flow fractionation techniques to explore the "nano-world".

    PubMed

    Contado, Catia

    2017-04-01

    Field flow fractionation (FFF) techniques are used to successfully characterize several nanomaterials by sizing nano-entities and producing information about the aggregation/agglomeration state of nanoparticles. By coupling FFF techniques to specific detectors, researchers can determine particle-size distributions (PSDs), expressed as mass-based or number-based PSDs. This review considers FFF applications in the food, biomedical, and environmental sectors, mostly drawn from the past 4 y. It thus underlines the prominent role of asymmetrical flow FFF within the FFF family. By concisely comparing FFF techniques with other techniques suitable for sizing nano-objects, the advantages and the disadvantages of these instruments become clear. A consideration of select recent publications illustrates the state of the art of some lesser-known FFF techniques and innovative instrumental set-ups.

  17. Synthesis and Electrochemical Properties of Nano-VO2 (B).

    PubMed

    Yang, Yun; Lu, Yong; Wang, Wei; Feng, Chuanqi; Yang, Shuijin

    2016-03-01

    The nano-VO2 (B) has been self-assembly synthesized by hydrothermal method using different templates, which may give them some interesting properties. The as-prepared samples were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties of the samples were investigated. The results show that the hexadecyltrimethyl ammonium bromide (CTAB) (soft template) was used to obtain the VO2 (B1) nanobelts. The flake graphite (hard template) was taken to get the VO2 (B2) nanosheets. The VO2 (B1) nanobelts have higher initial capacity to compare with VO2 (B2). But the VO2 (B2) nanosheets showed better cycling performance than that of VO2 (B1) nanobelts. The nano VO2 (B2) is a promising anode material for lithium ion battery application.

  18. Skyrmion Creation and Manipulation by Nano-Second Current Pulses

    PubMed Central

    Yuan, H. Y.; Wang, X. R.

    2016-01-01

    Easy creation and manipulation of skyrmions is important in skyrmion based devices for data storage and information processing. We show that a nano-second current pulse alone is capable of creating/deleting and manipulating skyrmions in a spin valve with a perpendicularly magnetized free layer and broken chiral symmetry. Interestingly, for an in-plane magnetized fixed layer, the free layer changes from a single domain at zero current to a Neel wall at an intermediate current density. Reverse the current polarity, the Neel wall changes to its image inversion. A properly designed nano-second current pulse, that tends to convert one type of Neel walls to its image inversion, ends up to create a stable skyrmion without assistance of external fields. For a perpendicularly magnetized fixed layer, the skyrmion size can be effectively tuned by a current density. PMID:26934954

  19. Terahertz pinch harmonics enabled by single nano rods.

    PubMed

    Park, Hyeong-Ryeol; Bahk, Young-Mi; Choe, Jong Ho; Han, Sanghoon; Choi, Seong Soo; Ahn, Kwang Jun; Park, Namkyoo; Park, Q-Han; Kim, Dai-Sik

    2011-11-21

    A pinch harmonic (or guitar harmonic) is a musical note produced by lightly pressing the thumb of the picking hand upon the string immediately after it is picked [J. Chem. Educ. 84, 1287 (2007)]. This technique turns off the fundamental and all overtones except those with a node at that location. Here we present a terahertz analogue of pinch harmonics, whereby a metallic nano rod placed at a harmonic node on a terahertz nanoresonator suppresses the fundamental mode, making the higher harmonics dominant. Strikingly, a skin depth-wide nano rod placed at the mid-point turns off all resonances. Our work demonstrates that terahertz electromagnetic waves can be tailored by nanoparticles strategically positioned, paving important path towards terahertz switching and detection applications.

  20. Thermal and electrical behavior of nano-modified cement mortar

    NASA Astrophysics Data System (ADS)

    Exarchos, D. A.; Dalla, P. T.; Tragazikis, I. K.; Alafogianni, P.; Barkoula, N.-M.; Paipetis, A. S.; Dassios, K. G.; Matikas, T. E.

    2014-04-01

    This research aims in characterizing modified cement mortar with carbon nanotubes (CNTs) that act as nanoreinforcements leading to the development of innovative materials possessing multi-functionality and smartness. Such multifunctional properties include enhanced mechanical behavior, electrical and thermal conductivity, and piezo-electric characteristics. The effective thermal properties of the modified nano-composites were evaluated using IR Thermography. The electrical resistivity was measured with a contact test method using a custom made apparatus and applying a known D.C. voltage. To eliminate any polarization effects the specimens were dried in an oven before testing. In this work, the thermal and electrical properties of the nano-modified materials were studied by nondestructively monitoring their structural integrity in real time using the intrinsic multi-functional properties of the material as damage sensors.

  1. Plasmonic-cavity model for radiating nano-rod antennas.

    PubMed

    Peng, Liang; Mortensen, N Asger

    2014-01-23

    In this paper, we propose the analytical solution of nano-rod antennas utilizing a cylindrical harmonics expansion. By treating the metallic nano-rods as plasmonic cavities, we derive closed-form expressions for both the internal and the radiated fields, as well as the resonant condition and the radiation efficiency. With our theoretical model, we show that besides the plasmonic resonances, efficient radiation takes advantage of (a) rendering a large value of the rods' radius and (b) a central-fed profile, through which the radiation efficiency can reach up to 70% and even higher in a wide frequency band. Our theoretical expressions and conclusions are general and pave the way for engineering and further optimization of optical antenna systems and their radiation patterns.

  2. Method for forming a nano-textured substrate

    DOEpatents

    Jeong, Sangmoo; Hu, Liangbing; Cui, Yi

    2015-04-07

    A method for forming a nano-textured surface on a substrate is disclosed. An illustrative embodiment of the present invention comprises dispensing of a nanoparticle ink of nanoparticles and solvent onto the surface of a substrate, distributing the ink to form substantially uniform, liquid nascent layer of the ink, and enabling the solvent to evaporate from the nanoparticle ink thereby inducing the nanoparticles to assemble into an texture layer. Methods in accordance with the present invention enable rapid formation of large-area substrates having a nano-textured surface. Embodiments of the present invention are well suited for texturing substrates using high-speed, large scale, roll-to-roll coating equipment, such as that used in office product, film coating, and flexible packaging applications. Further, embodiments of the present invention are well suited for use with rigid or flexible substrates.

  3. Controlling nitrogen migration through micro-nano networks.

    PubMed

    Cai, Dongqing; Wu, Zhengyan; Jiang, Jiang; Wu, Yuejin; Feng, Huiyun; Brown, Ian G; Chu, Paul K; Yu, Zengliang

    2014-01-14

    Nitrogen fertilizer unabsorbed by crops eventually discharges into the environment through runoff, leaching and volatilization, resulting in three-dimensional (3D) pollution spanning from underground into space. Here we describe an approach for controlling nitrogen loss, developed using loss control fertilizer (LCF) prepared by adding modified natural nanoclay (attapulgite) to traditional fertilizer. In the aqueous phase, LCF self-assembles to form 3D micro/nano networks via hydrogen bonds and other weak interactions, obtaining a higher nitrogen spatial scale so that it is retained by a soil filtering layer. Thus nitrogen loss is reduced and sufficient nutrition for crops is supplied, while the pollution risk of the fertilizer is substantially lowered. As such, self-fabrication of nano-material was used to manipulate the nitrogen spatial scale, which provides a novel and promising approach for the research and control of the migration of other micro-scaled pollutants in environmental medium.

  4. Equivalent-Continuum Modeling of Nano-Structured Materials

    NASA Technical Reports Server (NTRS)

    Odegard, Gregory M.; Gates, Thomas S.; Nicholson, Lee M.; Wise, Kristopher E.

    2001-01-01

    A method has been developed for modeling structure-property relationships of nano-structured materials. This method serves as a link between computational chemistry and solid mechanics by substituting discrete molecular structures with an equivalent-continuum model. It has been shown that this substitution may be accomplished by equating the vibrational potential energy of a nano-structured material with the strain energy of representative truss and continuum models. As an important example with direct application to the development and characterization of single-walled carbon nanotubes, the model has been applied to determine the effective continuum geometry of a graphene sheet. A representative volume element of the equivalent-continuum model has been developed with an effective thickness. This effective thickness has been shown to be similar to, but slightly smaller than, the interatomic spacing of graphite.

  5. Si-Ge Nano-Structured with Tungsten Silicide Inclusions

    NASA Technical Reports Server (NTRS)

    Mackey, Jon; Sehirlioglu, Alp; Dynys, Fred

    2014-01-01

    Traditional silicon germanium high temperature thermoelectrics have potential for improvements in figure of merit via nano-structuring with a silicide phase. A second phase of nano-sized silicides can theoretically reduce the lattice component of thermal conductivity without significantly reducing the electrical conductivity. However, experimentally achieving such improvements in line with the theory is complicated by factors such as control of silicide size during sintering, dopant segregation, matrix homogeneity, and sintering kinetics. Samples are prepared using powder metallurgy techniques; including mechanochemical alloying via ball milling and spark plasma sintering for densification. In addition to microstructural development, thermal stability of thermoelectric transport properties are reported, as well as couple and device level characterization.

  6. Generation of nano roughness on fibrous materials by atmospheric plasma

    NASA Astrophysics Data System (ADS)

    Kulyk, I.; Scapinello, M.; Stefan, M.

    2012-12-01

    Atmospheric plasma technology finds novel applications in textile industry. It eliminates the usage of water and of hazard liquid chemicals, making production much more eco-friendly and economically convenient. Due to chemical effects of atmospheric plasma, it permits to optimize dyeing and laminating affinity of fabrics, as well as anti-microbial treatments. Other important applications such as increase of mechanical resistance of fiber sleeves and of yarns, anti-pilling properties of fabrics and anti-shrinking property of wool fabrics were studied in this work. These results could be attributed to the generation of nano roughness on fibers surface by atmospheric plasma. Nano roughness generation is extensively studied at different conditions. Alternative explanations for the important practical results on textile materials and discussed.

  7. Ultralight Weight Optical Systems Using Nano-Layered Synthesized Materials

    NASA Technical Reports Server (NTRS)

    Clark, Natalie; Breckinridge, James

    2014-01-01

    Optical imaging is important for many NASA science missions. Even though complex optical systems have advanced, the optics, based on conventional glass and mirrors, require components that are thick, heavy and expensive. As the need for higher performance expands, glass and mirrors are fast approaching the point where they will be too large, heavy and costly for spacecraft, especially small satellite systems. NASA Langley Research Center is developing a wide range of novel nano-layered synthesized materials that enable the development and fabrication of ultralight weight optical device systems that enable many NASA missions to collect science data imagery using small satellites. In addition to significantly reducing weight, the nano-layered synthesized materials offer advantages in performance, size, and cost.

  8. The Catalytic Behaviour of NanoAg@montmorillonite Composite Materials

    NASA Astrophysics Data System (ADS)

    Karlíková, Martina; Kvítek, Libor; Prucek, Robert; Panáček, Aleš; Filip, Jan; Pechoušek, Jiří; Adegboyega, Nathaniel F.

    The preparation of nanoAg@montmorillonite composite materials and their catalytic activity is reported in this article. The nanoAg@montmorillonite composite materials were prepared by the adsorption of silver NPs, with an average size about 30 nm, from their aqueous dispersion onto two types of montmorillonite with different chemical composition. Silver NPs were prepared via modified Tollens process, which involves the reduction of [Ag(NH3)2]+ complex cation by maltose. The amount of silver NPs anchored onto the MMT surfaces was determined by UV-VIS spectroscopy; the decrease in absorbance of the dispersion after the adsorption was monitored. Prepared nanocomposite materials were subsequently characterized by means of transmission electron microscopy (TEM) and powder X-ray diffraction (XRD). The reduction of 4-nitrophenol by sodium borohydride was chosen to examine the catalytic properties of the synthesized silver nanocomposite materials.

  9. Studies on structural properties of clay magnesium ferrite nano composite

    SciTech Connect

    Kaur, Manpreet Singh, Mandeep; Jeet, Kiran Kaur, Rajdeep

    2015-08-28

    Magnesium ferrite-bentonite clay composite was prepared by sol-gel combustion method employing citric acid as complexing agent and fuel. The effect of clay on the structural properties was studied with X-ray diffraction (XRD), Fourier transform infrared (FT-IR) Spectroscopy, Scanning electron microscopy (SEM), SEM- Energy dispersive Spectroscope (EDS) and BET surface area analyzer. Decrease in particle size and density was observed on addition of bentonite clay. The BET surface area of nano composite containing just 5 percent clay was 74.86 m{sup 2}/g. Whereas porosity increased from 40.5 per cent for the pure magnesium ferrite to 81.0 percent in the composite showing that nano-composite has potential application as an adsorbent.

  10. Hierarchical periodic micro/nano-structures on nitinol and their influence on oriented endothelialization and anti-thrombosis.

    PubMed

    Nozaki, Kosuke; Shinonaga, Togo; Ebe, Noriko; Horiuchi, Naohiro; Nakamura, Miho; Tsutsumi, Yusuke; Hanawa, Takao; Tsukamoto, Masahiro; Yamashita, Kimihiro; Nagai, Akiko

    2015-12-01

    The applications of hierarchical micro/nano-structures, which possess properties of two-scale roughness, have been studied in various fields. In this study, hierarchical periodic micro/nano-structures were fabricated on nitinol, an equiatomic Ni-Ti alloy, using a femtosecond laser for the surface modification of intravascular stents. By controlling the laser fluence, two types of surfaces were developed: periodic nano- and micro/nano-structures. Evaluation of water contact angles indicated that the nano-surface was hydrophilic and the micro/nano-surface was hydrophobic. Endothelial cells aligned along the nano-structures on both surfaces, whereas platelets failed to adhere to the micro/nano-surface. Decorrelation between the responses of the two cell types and the results of water contact angle analysis were a result of the pinning effect. This is the first study to show the applicability of hierarchical periodic micro/nano-structures for surface modification of nitinol.

  11. In Conversation with Jim Schuck: Nano-optics

    SciTech Connect

    Jim Schuck and Alice Egan

    2009-08-07

    Sponsored by Berkeley Lab's Materials Sciences Division (MSD), "In Conversation with" is a next generation science seminar series. Host Alice Egan is the assistant to MSD Director Miquel Salmeron. Alice conducts a fun and informative interview, touching on the lives and work of the guest. The first In Conversation With took place July 9 with Jim Schuck, a staff scientist in the Molecular Foundry's Imaging and Manipulation Facility as our first guest. He discussed the world of Nano-optics.

  12. Nano-spectroscopy and chemical nanoscopy of biomaterials

    SciTech Connect

    Bruendermann, E.; Schmidt, D. A.; Kopf, I.; Havenith, M.

    2010-02-03

    A scanning near-field infrared microscopy experimental station will be integrated into the ANKA-IR2 beamline to combine broadband synchrotron radiation with near-field microscopy. Other microscopy techniques also available in the station will be compared. We have performed nano-spectroscopy investigating biomaterials like self-assembled monolayers and nanoscale lipid membranes. Coherent synchrotron radiation (CSR) at ANKA has been measured to determine power and beam profile for coupling terahertz radiation to the nanoscope.

  13. Nano and Biological Technology Panel: Quantum Information Science

    DTIC Science & Technology

    2008-12-03

    Electrical Engineering & Telecommunications The University of New South Wales Nano and Biological Technology Panel: Quantum Information Science 26th US Army...Technology Panel: Quantum Information Science 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e. TASK...Business School Summary – Quantum Information Science • Quantum information technologies now a reality • First impacts will be secure communications

  14. UV Nano-Lights: Nonlinear Quantum Dot-Plasmon Coupling

    DTIC Science & Technology

    2014-08-01

    Final 3. DATES COVERED (From - To) 11-Mar-2013 to 10-Mar-2014 4. TITLE AND SUBTITLE UV Nano-Lights: Nonlinear Quantum Dot- Plasmon ...Nonlinear Quantum Dot- Plasmon Coupling 5a. CONTRACT NUMBER FA2386-13-1-4016 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) Eric...nonlinear emission from Quantum Dots through Plasmon Coupling PERIOD OF PERFORMANCE 11 March 2013 - 11 March 2014 RECIPIENT PRINCIPAL

  15. Determining the Cost Effectiveness of Nano-Satellites

    DTIC Science & Technology

    2014-09-01

    mechanical components enabled significant computing and sensing power in increasingly small packages. Solar cell improvements led to greatly...10 4. Data Downlink Nano-satellites are generally very power limited due to the very small solar arrays available. The transmitter is one...Unclassified 19. SECURITY CLASSIFICATION OF ABSTRACT Unclassified 20. LIMITATION OF ABSTRACT U NSN 7540–01-280-5500 Standard Form 298 (Rev. 2–89

  16. Stress development in particulate, nano-composite and polymeric coatings

    NASA Astrophysics Data System (ADS)

    Jindal, Karan

    2009-12-01

    The main goal of this research is to study the stress, structural and mechanical property development during the drying of particulate coatings, nano-composite coatings and VOC compliant refinish clearcoats. The results obtained during this research establish the mechanism for the stress development during drying in various coating systems. Coating stress was measured using a controlled environment stress apparatus based on cantilever deflection principle. The stress evolution in alumina coatings made of 0.4 mum size alumina particles was studied and the effect of a lateral drying was investigated. The stress does not develop until the later stages of drying. A peak stress was observed during drying and the peak stress originates due to the formation of pendular rings between the particles. Silica nanocomposite coatings were fabricated from suspension of nano sized silicon dioxide particles (20 nm) and polyvinyl alcohol (PVA) polymer. The stress in silica nano-composite goes through maximum as the amount of polymer in the coating increases. The highest final stress was found to be ˜ 110MPa at a PVA content of 60 wt%. Observations from SEM, nitrogen gas adsorption, camera imaging, and nano-indentation were also studied to correlate the coatings properties during drying to measured stress. A model VOC compliant two component (2K) acrylic-polyol refinish clearcoat was prepared to study the effects of a new additive on drying, curing, rheology and stress development at room temperature. Most of the drying of the low VOC coatings occurred before appreciable (20%) crosslinking. Tensile stress developed in the same timeframe as drying and then relaxed over a longer time scale. Model low VOC coatings prepared with the additive had higher peak stresses than those without the additive. In addition, rheological data showed that the additive resulted in greater viscosity buildup during drying.

  17. Construction of a DNA Nano-Object Directly Demonstrates Computation

    PubMed Central

    Wu, Gang; Jonoska, Natasha; Seeman, Nadrian C.

    2009-01-01

    We demonstrate a computing method in which a DNA nano-object representing the solution of a problem emerges as a result of self-assembly. We report an experiment in which three-vertex colorability for a 6-vertex graph with 9 edges is solved by constructing a DNA molecule representing the colored graph itself. Our findings show that computation based on “shape processing” is a viable alternative to symbol processing when computing by molecular self-assembly. PMID:19607875

  18. Fabricated nano-fiber diameter as liquid concentration sensors

    NASA Astrophysics Data System (ADS)

    Chyad, Radhi M.; Mat Jafri, Mohd Zubir; Ibrahim, Kamarulazizi

    Nanofiber is characterized by thin, long, and very soft silica. Taper fibers are made using an easy and low cost chemical method. Etching is conducted with a HF solution to remove cladding and then a low molarity HF solution to reduce the fiber core diameter. One approach to on-line monitoring of the etching process uses spectrophotometer with a white light source. In the aforementioned technique, this method aims to determine the diameter of the reduced core and show the evolution of the two different processes from the nanofiber regime to the fixed regime in which the mode was remote from the surrounding evanescent field, intensity can propagate outside the segment fiber when the core diameter is less than 500 nm. Manufacturing technologies of nano-fiber sensors offer a number of approved properties of optical fiber sensors utilized in various sensory applications. The nano-fiber sensor is utilized to sense the difference in the concentration of D-glucose in double-distilled deionized water and to measure the refractive index (RI) of a sugar solution. Our proposed method exhibited satisfactory capability based on bimolecular interactions in the biological system. The response of the nano-fiber sensors indicates a different kind of interaction among various groups of AAs. These results can be interpreted in terms of solute-solute and solute-solvent interactions and the structure making or breaking ability of solutes in the given solution. This study utilized spectra photonics to measure the transmission of light through different concentrations of sugar solution, employing cell cumber and nano-optical fibers as sensors.

  19. Positron Annihilation Studies In Polymer Nano-Composites

    SciTech Connect

    Chen, H. M.; Awad, Somia; Jean, Y. C.; Yang, J.; Lee, L. James

    2011-06-01

    Positron annihilation spectroscopy coupled with a variable mono-energy positron beam has been applied to study nanoscale polymeric nanocomposites. New information about multilayer depth profiles and structures, interfacial free-volume and open space properties have been obtained in polystyrene/carbon nano fiber composites. The S parameter in Doppler Broadening Energy Spectra combined slow positron beam is used to quantitatively represent the free volume, open spaces, and interactions in the interface between polystyrene matrix and carbon nanofibers.

  20. Micro- and nano-scale optoelectronic devices using vanadium dioxide

    NASA Astrophysics Data System (ADS)

    Joushaghani, Arash

    Miniaturization has the potential to reduce the size, cost, and power requirements of active optical devices. However, implementing (sub)wavelength-scale electro-optic switches with high efficiency, low insertion loss, and high extinction ratios remains challenging due to their small active volumes. Here, we use the insulator-metal phase transition of vanadium dioxide (VO2), which exhibits a large and reversible change in the refractive index across the phase transition to demonstrate compact, broadband, and efficient switches and photodetectors with record-setting characteristics. We begin by analyzing the electrical and optical properties of VO2 thin films across the phase transition and discuss the fabrication processes that yield micron- and nano-scale VO2 devices. We then demonstrate a surface plasmon thermo-optic switch, which achieves an extinction ratio of 10 dB in a 5 um long device, a record for plasmonic devices. The switch operates over a 100 nm optical bandwidth, and exhibits a thermally limited switching time of 40 mus. We investigate the current and voltage induced switching of VO2 in nano-gap junctions and show optical switching times as short as 20 ns. The two terminal VO2 junctions are incorporated in a silicon photonics platform to yield silicon-VO2 hybrid waveguide devices with a record extinction ratio of 12 dB in a 1 mum long device. In photodetector mode, the devices exhibit a nonlinear responsivity greater than 12 A/W for optical powers less than 1 muW. This device is the smallest electrically controlled and integrated switch and photodetector capable of achieving extinction ratios > 10 dB/mum. We finally investigate the ultra-fast thermal heating in gold nano-apertures and demonstrate that electron heating can change the gold lattice temperature by 300 K in tens of picoseconds. These nano-apertures can be hybridized with VO2 to demonstrate high extinction and ultrafast optical switches.

  1. Nano-JASMINE: A 10-kilogram Satellite For Space Astrometry

    NASA Astrophysics Data System (ADS)

    Kobayashi, Y.; Gouda, N.; Yano, T.; Suganuma, M.; Yamauchi, M.; Yamada, Y.

    The current status of the nanoJASMINE project is presented Nano-JASMINE--a very small satellite weighing less than 10 kg -- aims to carry out astrometry measurements on nearby bright stars This satellite adopts the same observation technique used by the HIPPARCOS satellite In this technique simultanaeously measurements of two different fields separated by an angle that is greater than 90 degrees is carried out these measurements are carried out in the course of continuous scanning observations of the whole sky This technique enables us to distinguish between the irregularty in the spin velocity and stellar position distribution The major technical differrence between the nano-JASMINE and the HIPPARCOS satellite is the utilization of a CCD sensor device that makes it possible to achieve comparable astrometry accuracy by using an extremly smaller telescope We developed a prototype system and evaluated its performance The telescope is composed entirely of alminum A 5-cm telecsope including an aluminum beam combiner The telescope is based on the standard Richey-Chretian optical system and has a composit f ratio of 33 that enables the match of the Airy disk size to three times of the CCD pixel size of 15um The full depletion CCD will be used in the time delayed and integration TDI mode in order to efficiently survey the whole sky in the near-infrared wavelength The nano-JASMINE satellite is scheduled for launch in 2008 as a piggyback system We expected the satellite to measure the position and proper motion of bright stars mz 7 5 with an

  2. Ecotoxicity of selected nano-materials to aquatic organisms.

    PubMed

    Blaise, C; Gagné, F; Férard, J F; Eullaffroy, P

    2008-10-01

    Present knowledge concerning the ecotoxic effects of nano-materials is very limited and merits to be documented more fully. For this purpose, we appraised the toxicity of nine metallic nano-powders (copper zinc iron oxide, nickel zinc iron oxide, yttrium iron oxide, titanium dioxide, strontium ferrite, indium tin oxide, samarium oxide, erbium oxide, and holmium oxide) and of two organic nano- powders (fullerene-C60 and single-walled carbon nanotube or SWCNT). After a simple process where nano-powders (NPs) were prepared in aqueous solution and filtered, they were then bioassayed across several taxonomic groups including decomposers (bacteria), primary producers (micro-algae), as well as primary and secondary consumers (micro-invertebrates and fish). Toxicity data generated on the 11 NPs reflected a wide spectrum of sensitivity that was biological level-, test-, and endpoint-specific. With all acute and chronic tests confounded for these 11 NPs, toxicity responses spanned over three orders of magnitude: >463 mg/L (24 h LC50 of the invertebrate Thamnoplatyurus platyurus for fullerene-C60) / 0.3 mg/L (96 h EC50 of the invertebrate Hydra attenuata for indium tin oxide), that is a ratio of 1543. On the basis of the MARA (Microbial Array for Risk Assessment) assay toxic fingerprint concept, it is intimated that NPs may have different modes of toxic action. When mixed in a 1:1 ratio with a certified reference material (CRM) sediment, two solid phase assays and an elutriate assay, respectively, showed that five NPs (copper zinc iron oxide, samarium oxide, erbium oxide, holmium oxide, and SWCNT) were able to increase both CRM sediment toxicity and its elutriate toxicity. This initial investigation suggests that chemicals emerging from nanotechnology may pose a risk to aquatic life in water column and sediment compartments and that further studies on their adverse effects are to be encouraged.

  3. The nano-plasma interface: Implications of the protein corona.

    PubMed

    Wolfram, Joy; Yang, Yong; Shen, Jianliang; Moten, Asad; Chen, Chunying; Shen, Haifa; Ferrari, Mauro; Zhao, Yuliang

    2014-12-01

    The interactions between nanoparticles and macromolecules in the blood plasma dictate the biocompatibility and efficacy of nanotherapeutics. Accordingly, the properties of nanoparticles and endogenous biomolecules change at the nano-plasma interface. Here, we review the implications of such changes including toxicity, immunological recognition, molecular targeting, biodistribution, intracellular uptake, and drug release. Although this interface poses several challenges for nanomedicine, it also presents opportunities for exploiting nanoparticle-protein interactions.

  4. A review of nano-optics in metamaterial hybrid heterostructures

    SciTech Connect

    Singh, Mahi R.

    2014-03-31

    We present a review for the nonlinear nano-optics in quantum dots doped in a metamaterial heterostructure. The heterostructure is formed by depositing a metamaterial on a dielectric substrate and ensemble of noninteracting quantum dots are doped near the heterostructure interface. It is shown that there is enhancement of the second harmonic generation due to the surface plasmon polaritons field present at the interface.

  5. Nano-booms — A new class of WIMP detectors

    NASA Astrophysics Data System (ADS)

    Drukier, A. K.; Fagaly, R. L.; Bielski, R.

    2014-07-01

    Weakly Interacting Massive Particles (WIMPs) can constitute a large fraction of the dark matter (DM) in the universe. The importance of coherent scattering and detection of annual modulation effect (AME), diurnal modulation effect (DME) and direction sensitive AME was documented. In particular, DAMA/NaI and DAMA/LIBRA have released data collected during 14 annual cycles, which support in model independent way, the presence of DM particles in the galactic halo. There is a clear evidence of AME signature in DAMA data. Recently, positive hints have also been reported by CoGeNT on AME signature in Ge, while CREST-II and CDMS-Si have published some events in excess of estimated background; these events are compatible with WIMP-like candidates. If these results would be analyzed all together in some WIMP scenario, one could derive: MDM < 10 GeV/c2. Current generation of detectors is far from being optimal or in some cases even reliable when MDM approaches 5 GeV/c2. We propose a detector, which can detect the direction of incoming WIMPs. This paper focus on a particular implementation of the new class of nano-explosive DM detectors. The local heating ignites an explosion, which release chemical energy stored in such a nano-grain. Use of two component nano-explosive permits to amplify the bolometric effect due to WIMP-candidates. The energy available becomes 100,000-fold larger than the energy initially deposited by DM candidate. This leads to a sonic-boom, which can be detected remotely. This new class of nano-explosive detectors may be especially important in detection of WIMPs with very low mass, say MDM = O(5 GeV/c2). We describe a configuration, which leads to explosive-triode, and permits detection of the direction of incoming WIMPs.

  6. Micro-Combustion for Nano and Pico Satellite Propulsion Systems

    DTIC Science & Technology

    2003-05-20

    The performance of millimeter-scale combustors intended for micro , nano , and pico-satellite propulsion is strongly influenced by heat exchange to and...within the combustor structure. The purpose of this work is to develop models for the effects of fluid-structure coupling on combustion in micro ...conductive structure. The important findings were that heat exchange between the gas and structure in micro -combustors can increase the burning rate and the

  7. Fabrication and Characterization of Nano-Optic Devices

    DTIC Science & Technology

    2001-04-01

    FINAL 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS FABRICATION AND CHARACTERIZATION OF NANO -OPTIC DEVICES 6. AUTHOR(S) PROFESSOR SCHERER 7. PERFORMING...has to be pumped to overcome lasing threshold. This compares to thousands of modes which have to be pumped in conventional semiconductor lasers in...lasers, advances in high speed lasers and detectors, low power micro -optical interconnects, and high efficiency LEDs for illumination and display

  8. NanoBench: An Individually Addressable Nanotube Array

    DTIC Science & Technology

    2006-03-25

    fabricate and install hardware to place NanoBench and cells in a vacuum system, and to acquire data/signals from the nanoprobes with an electron beam in a...picosecond temporal resolution (20GHz frequency response).11 9 Rutten, WLC, "Selective electrical interfaces with the nervous system". Ann Rev Biomed Eng., 4...vitro. Thereafter, we will perform cyclic voltammetry using e-beam charging and reading as described earlier. In addition, the CNT nanoelectrodes

  9. Programmable bio-nano-chip system for saliva diagnostics

    NASA Astrophysics Data System (ADS)

    Christodoulides, Nicolaos; De La Garza, Richard; Simmons, Glennon W.; McRae, Michael P.; Wong, Jorge; Kosten, Thomas R.; Miller, Craig S.; Ebersole, Jeffrey L.; McDevitt, John

    2014-06-01

    This manuscript describes programmable Bio-Nano-Chip (p-BNC) approach that serves as miniaturized assay platform designed for the rapid detection and quantitation of multiple analytes in biological fluids along with the specific applications in salivary diagnostics intended for the point of need (PON). Included here are oral fluid-based tests for local periodontal disease, systemic cardiac disease and multiplexed tests for drugs of abuse.

  10. Why does one nano lab cost more than another?

    NASA Astrophysics Data System (ADS)

    Wilson, William; Reed, Mark

    2005-08-01

    The label "nanotechnology" covers a host of research applications, some of which require vastly more costly infrastructure than others. Basic engineering issues, research themes, and design choices determine the budget of the nanotech facility. When designing a nano lab, the users and the architect face a number of decisions about the performance of the space and the costs associated with achieving the performance criteria. These choices and recommendations are outlined in this paper.

  11. New York Nano-Bio Molecular Information Technology (NYNBIT) Incubator

    SciTech Connect

    Das, Digendra K

    2008-12-19

    This project presents the outcome of an effort made by a consortium of six universities in the State of New York to develop a Center for Advanced technology (CAT) in the emerging field of Nano-Bio-Molecular Information Technology. The effort consists of activities such as organization of the NYNBIT incubator, collaborative research projects, development of courses, an educational program for high schools, and commercial start-up programs.

  12. Nano-Enabled Technologies for Naval Aviation Applications

    DTIC Science & Technology

    2015-06-05

    nano-structured non-precious metal catalysts for Fuel Cells, and phase change materials for thermal management. This paper reports the results of the...provided improved catalysts can be identified, improved conductivity for sulfur addressed, and improved membranes developed. In summary, addressing...2. Mitigation of internal cell shorts Emerging Chemistries 1. Li-Air 1. Catalyst for redox reaction 2. Electrolytes 3. O2-only

  13. Tomography and optical properties of silver nano-inukshuk

    SciTech Connect

    Ghosh, Tanmay; Das, Pabitra; Ghosh, Tapas; Satpati, Biswarup

    2015-06-24

    Following a simple dip-and-rinse galvanic displacement reaction silver nano-inukshuks were prepared directly on germanium surfaces. Morphology, 3-dimensional (3D) structure, chemical composition and optical properties of the silver nanostructurs were investigated using scanning electron microscopy (SEM), scanning transmission electron microscopy (STEM), energy-dispersive X-ray spectroscopy (EDX), and cathodoluminescence (CL) spectroscopy. Exact 3D morphology was reconstructed in the by tomography mode of TEM.

  14. In Conversation with Jim Schuck: Nano-optics

    ScienceCinema

    Jim Schuck and Alice Egan

    2016-07-12

    Sponsored by Berkeley Lab's Materials Sciences Division (MSD), "In Conversation with" is a next generation science seminar series. Host Alice Egan is the assistant to MSD Director Miquel Salmeron. Alice conducts a fun and informative interview, touching on the lives and work of the guest. The first In Conversation With took place July 9 with Jim Schuck, a staff scientist in the Molecular Foundry's Imaging and Manipulation Facility as our first guest. He discussed the world of Nano-optics.

  15. Nano-structured polymer composites and process for preparing same

    DOEpatents

    Hillmyer, Marc; Chen, Liang

    2013-04-16

    A process for preparing a polymer composite that includes reacting (a) a multi-functional monomer and (b) a block copolymer comprising (i) a first block and (ii) a second block that includes a functional group capable of reacting with the multi-functional monomer, to form a crosslinked, nano-structured, bi-continuous composite. The composite includes a continuous matrix phase and a second continuous phase comprising the first block of the block copolymer.

  16. Slip casting nano-particle powders for making transparent ceramics

    SciTech Connect

    Kuntz, Joshua D.; Soules, Thomas F.; Landingham, Richard Lee; Hollingsworth, Joel P.

    2011-04-12

    A method of making a transparent ceramic including the steps of providing nano-ceramic powders in a processed or unprocessed form, mixing the powders with de-ionized water, the step of mixing the powders with de-ionized water producing a slurry, sonifing the slurry to completely wet the powder and suspend the powder in the de-ionized water, separating very fine particles from the slurry, molding the slurry, and curing the slurry to produce the transparent ceramic.

  17. Ultrasensitive detection of endotoxins using computationally designed nanoMIPs.

    PubMed

    Altintas, Zeynep; Abdin, Mohammed J; Tothill, Alexander M; Karim, Kal; Tothill, Ibtisam E

    2016-09-07

    Novel molecularly imprinted polymer nanoparticles (nanoMIPs) were designed for endotoxin from Escherichia coli 0111:B4, using computational modeling. The screening process based on binding energy between endotoxin and each monomer was performed with 21 commonly used monomers, resulting in the selection of itaconic acid, methacrylic acid and acrylamide as functional monomers due to their strong binding interaction with the endotoxin template. The nanoMIPs were successfully synthesized with functional groups on the outer surface to aid in the immobilization onto sensor surface. The solid phase photopolymerization approach used for the synthesis of nanoMIPs ranging from 200 to 235 nm in diameter. The limit of detection and KD were significantly improved when endotoxin samples were prepared using a novel triethylamine method. This improved the efficiency of gold nanoparticle functionalization by targeting the subunits of the endotoxin. Compared to the vancomycin MIP control, the endotoxin MIPs displayed outstanding affinity and selectivity towards the endotoxin with KD values in the range of 4.4-5.3 × 10(-10) M, with limits of detection of 0.44 ± 0.02 ng mL(-1) as determined by surface plasmon resonance (SPR) sensor when itaconic acid was used as the functional monomer. The MIP surface can be regenerated >30 times without significant loss of binding activity making this approach highly cost effective for expensive analyte templates. The combination of molecular modeling and solid phase synthesis enabled the successful synthesis of nanoMIPs capable of recognition and ultrasensitive detection of endotoxins using the highly sensitive SPR biosensor with triethylamine method.

  18. PREFACE: International Conference on Theoretical Physics: Dubna-Nano 2012

    NASA Astrophysics Data System (ADS)

    Osipov, Vladimir; Nesterenko, Valentin; Shukrinov, Yury M.

    2012-11-01

    The International Conference 'Dubna-Nano2012' was held on 9-14 July 2012 at the Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna, Moscow region, Russia. The conference was the third one in the series started in 2008. 'Dubna-Nano2012' provided an opportunity for presentations and discussions about theoretical and experimental advances in the rapidly growing area of nanophysics. The multidisciplinary character of the conference allowed an effective exchange of ideas between different areas of nanophysics. The following topics were covered: graphene and other carbon nanostructures, topological insulators, quantum transport, quantum dots, atomic clusters, Josephson junctions and applications of nanosystems. About 100 scientists from 22 countries participated in the conference. The program included 38 oral talks and 39 posters. This volume contains 35 contributions. We would like to express our gratitude to all participants for their presentations and discussions. We are deeply indebted to the members of the International Advisory Committee Professors K S Novoselov, T Ando, T Chakraborty, J Fabian, V M Galitski, F Guinea, M Z Hasan, P Hawrylak, K Kadowaki, R Kleiner, T Koyama, Yu I Latyshev, Yu E Lozovik, M Machida, B K Nikolic, N F Pedersen, P-G. Reinhard, J M Rost and A Ya Vul. Financial support from BLTP JINR, Russian Foundation for Basic Research, Heisenberg-Landau Program and Bogoliubov-Infeld Program was of a great importance. Further information about 'Dubna-Nano2012' is available on the homepage http://theor.jinr.ru/~nano12. Vladimir Osipov, Valentin Nesterenko and Yury Shukrinov Editors

  19. Temperature dependent phase transformation in nano sized magnesium ferrite

    NASA Astrophysics Data System (ADS)

    Sumangala T., P.; Mahender, C.; Venkataramani, N.; Prasad, Shiva

    2015-06-01

    The phase transformation in nanosized stoichiometric magnesium ferrite is being discussed. It was shown by TGA/DSC that there exist two reactions (shown by exothermic peaks) in nano sized magnesium ferrite when synthesized by sol gel combustion synthesis. First one of these reactions resulted in the precipitation of α-Fe2O3 and a resultant spinel. The second reaction resulted in stoichiometric spinel from this two phase system.

  20. Structured electron beams from nano-engineered cathodes

    NASA Astrophysics Data System (ADS)

    Lueangaramwong, A.; Mihalcea, D.; Andonian, G.; Piot, P.

    2017-03-01

    The ability to engineer cathodes at the nano-scale have opened new possibilities such as enhancing quantum efficiency via surface-plasmon excitation, forming ultra-low-emittance beams, or producing structured electron beams. In this paper, we present numerical investigations of the beam dynamics associated with this class of cathode in the weak- and strong-field regimes. We finally discuss the possible applications of some of the achievable cathode patterns when coupled with other phase space manipulations.

  1. Graphene nano-devices and nano-composites for structural, thermal and sensing applications

    NASA Astrophysics Data System (ADS)

    Yavari, Fazel

    In this dissertation we have developed graphene-based nano-devices for applications in integrated circuits and gas sensors; as well as graphene-based nano-composites for applications in structures and thermal management. First, we have studied the bandgap of graphene for semiconductor applications. Graphene as a zero-bandgap material cannot be used in the semiconductor industry unless an effective method is developed to open the bandgap in this material. We have demonstrated that a bandgap of 0.206 eV can be opened in graphene by adsorption of water vapor molecules on its surface. Water molecules break the molecular symmetries of graphene resulting in a significant bandgap opening. We also illustrate that the lack of bandgap in graphene can be used to our advantage by making sensors that are able to detect low concentrations of gas molecules mixed in air. We have shown that 1-2 layers of graphene synthesized by chemical vapor deposition enables detection of trace amounts of NO 2 and NH3 in air at room temperature and atmospheric pressure. The gas species are detected by monitoring changes in electrical resistance of the graphene film due to gas adsorption. The sensor response time is inversely proportional to the gas concentration. Heating the film expels chemisorbed molecules from the graphene surface enabling reversible operation. The detection limits of ~100 parts-per-billion (ppb) for NO2 and ~500 ppb for NH3 obtained using this device are markedly superior to commercially available NO2 and NH3 detectors. This sensor is fabricated using individual graphene sheets that are exquisitely sensitive to the chemical environment. However, the fabrication and operation of devices that use individual nanostructures for sensing is complex, expensive and suffers from poor reliability due to contamination and large variability from sample-to-sample. To overcome these problems we have developed a gas sensor based on a porous 3D network of graphene sheets called graphene foam

  2. Method of producing exfoliated graphite, flexible graphite, and nano-scaled graphene platelets

    DOEpatents

    Zhamu, Aruna; Shi, Jinjun; Guo, Jiusheng; Jang, Bor Z.

    2010-11-02

    The present invention provides a method of exfoliating a layered material (e.g., graphite and graphite oxide) to produce nano-scaled platelets having a thickness smaller than 100 nm, typically smaller than 10 nm. The method comprises (a) dispersing particles of graphite, graphite oxide, or a non-graphite laminar compound in a liquid medium containing therein a surfactant or dispersing agent to obtain a stable suspension or slurry; and (b) exposing the suspension or slurry to ultrasonic waves at an energy level for a sufficient length of time to produce separated nano-scaled platelets. The nano-scaled platelets are candidate reinforcement fillers for polymer nanocomposites. Nano-scaled graphene platelets are much lower-cost alternatives to carbon nano-tubes or carbon nano-fibers.

  3. Facile and novel synthetic method to prepare nano molybdenum and its catalytic activity.

    PubMed

    Sam Jaikumar, Sugumaran; Yuvakkumar, Rathinam; Suriya Prabha, Rangaraj; Karunakaran, Gopalu; Rajendran, Venkatachalam; Hong, Sun Ig

    2015-08-01

    This study reports on a facile and economical synthetic method to prepare nano molybdenum by solid-state reaction technique. Metallic nano molybdenum was synthesised from molybdenum trioxide, molybdenum IV oxide and molybdenum VI oxide through thermal decomposition technique. Metallic nano molybdenum prepared from molybdenum IV oxide was used to study the catalytic effect of molybdenum nanoparticles on the growth of Anabaena sp. The increase in concentration of nano molybdenum from 0.1 to 100% in BG11 (N⁻ Mo⁻ + nano Mo) medium increases heterocyst frequency. The chlorophyll and protein content in Anabaena sp. was found to improve when compared with bulk molybdenum particles and showed a positive influence to be used as a nano nutrient for Anabaena sp.

  4. Generation of exogenous germ cells in the ovaries of sterile NANOS3-null beef cattle

    PubMed Central

    Ideta, Atsushi; Yamashita, Shiro; Seki-Soma, Marie; Yamaguchi, Ryosaku; Chiba, Shiori; Komaki, Haruna; Ito, Tetsuya; Konishi, Masato; Aoyagi, Yoshito; Sendai, Yutaka

    2016-01-01

    Blastocyst complementation (BC) systems have enabled in vivo generation of organs from allogeneic pluripotent cells, compensating for an empty germ cell niche in gene knockout (KO) animals. Here, we succeeded in producing chimeric beef cattle (Wagyu) by transferring allogenic germ cells into ovaries using somatic cell nuclear transfer and BC technology. The KO of NANOS3 (NANOS3−/−) in Wagyu bovine ovaries produced a complete loss of germ cells. Holstein blastomeres (NANOS3+/+) were injected into NANOS3−/− Wagyu embryos. Subsequently, exogenous germ cells (NANOS3+/+) were identified in the NANOS3−/− ovary. These results clearly indicate that allogeneic germ cells can be generated in recipient germ cell-free gonads using cloning and BC technologies. PMID:27117862

  5. Generation of exogenous germ cells in the ovaries of sterile NANOS3-null beef cattle.

    PubMed

    Ideta, Atsushi; Yamashita, Shiro; Seki-Soma, Marie; Yamaguchi, Ryosaku; Chiba, Shiori; Komaki, Haruna; Ito, Tetsuya; Konishi, Masato; Aoyagi, Yoshito; Sendai, Yutaka

    2016-04-27

    Blastocyst complementation (BC) systems have enabled in vivo generation of organs from allogeneic pluripotent cells, compensating for an empty germ cell niche in gene knockout (KO) animals. Here, we succeeded in producing chimeric beef cattle (Wagyu) by transferring allogenic germ cells into ovaries using somatic cell nuclear transfer and BC technology. The KO of NANOS3 (NANOS3(-/-)) in Wagyu bovine ovaries produced a complete loss of germ cells. Holstein blastomeres (NANOS3(+/+)) were injected into NANOS3(-/-) Wagyu embryos. Subsequently, exogenous germ cells (NANOS3(+/+)) were identified in the NANOS3(-/-) ovary. These results clearly indicate that allogeneic germ cells can be generated in recipient germ cell-free gonads using cloning and BC technologies.

  6. Light diffusing effects of nano and micro-structures on OLED with microcavity.

    PubMed

    Cho, Doo-Hee; Shin, Jin-Wook; Joo, Chul Woong; Lee, Jonghee; Park, Seung Koo; Moon, Jaehyun; Cho, Nam Sung; Chu, Hye Yong; Lee, Jeong-Ik

    2014-10-20

    We examined the light diffusing effects of nano and micro-structures on microcavity designed OLEDs. The results of FDTD simulations and experiments showed that the pillar shaped nano-structure was more effective than the concave micro-structure for light diffusing of microcavity OLEDs. The sharp luminance distribution of the microcavity OLED was changed to near Lambertian luminance distribution by the nano-structure, and light diffusing effects increased with the height of the nano-structure. Furthermore, the nano-structure has advantages including light extraction of the substrate mode, reproducibility of manufacturing process, and minimizing pixel blur problems in an OLED display panel. The nano-structure is a promising candidate for a light diffuser, resolving the viewing angle problems in microcavity OLEDs.

  7. Friction, wear, and tensile properties of vacuum hot pressing crosslinked UHMWPE/nano-HAP composites.

    PubMed

    Xiong, Lei; Xiong, Dangsheng; Yang, Yuanyuan; Jin, Jiabo

    2011-07-01

    Ultra high molecular weight polyethylene (UHMWPE) is a thermoplastic engineering plastic with excellent mechanical properties. In this study, nonirradiated and irradiated UHMWPE/nano-hydroxyapatite (nano-HAP) composites were prepared by vacuum hot-pressing method, and then friction, wear, and tensile properties were investigated. To explore mechanisms of these properties, differential scanning calorimetry, infrared spectrum, and scanning electron microscopy with energy dispersive spectrometry analysis were carried out on the samples. The results in this study indicated that reduced friction coefficients and wear rate could be obtained when nonirradiated and irradiated UHMWPE were filled with 7% nano-HAP. The irradiated UHMWPE/7% nano-HAP also had a synergistic function of wear reduction as compared with irradiated UHMWPE and nonirradiated UHMWPE/7% nano-HAP. Samples filled with 7% nano-HAP showed a brittle fracture behavior, and a linear relationship between modulus and crystallinity for a nonirradiated and irradiated sample was found in this study.

  8. Stimuli responsive drug delivery systems based on nano-graphene for cancer therapy.

    PubMed

    Yang, Kai; Feng, Liangzhu; Liu, Zhuang

    2016-10-01

    Nano-graphene as a class of two-dimensional sp(2) carbon nanomaterial has attracted tremendous attentions in various fields in the past decade. Utilizing its unique physical and chemical properties, nano-graphene has also shown great promises in the area of biomedicine, for application in biosensing, imaging and therapy. In particular, with all atoms exposed on its surface, nano-graphene exhibits ultra-high surface area available for efficient binding/loading of various biomolecules of interests, and has been widely used as multifunctional nano-carriers for drug and gene delivery. In this review article, we will summarize the recent advances in the development of nano-graphene as stimuli-responsive nano-carriers for drug delivery, as well as the applications of these smart systems for cancer therapy.

  9. Evaluation of the Nano-TiO2 as a Novel Deswelling Material.

    PubMed

    Chu, Ming; Hou, Yue-Long; Xu, Lan; Chu, Zheng-Yun; Zhang, Ming-Bo; Wang, Yue-Dan

    2016-01-04

    Nano-TiO2 is widely applied in the automobile exhaust hose reels as a catalyst to reduce oxynitride emissions, including nitric oxide (NO). In the biomedicine field, NO plays an important role in vasodilation and edema formation in human bodies. However, the deswelling activity of nano-TiO2 has not been reported. Here, we demonstrated that nano-TiO2 can significantly degrade the production of NO in LPS-induced RAW264.7 mouse macrophages. Further study indicated that nano-TiO2 exhibited an effect on vascular permeability inhibition, and prevented carrageenan-induced footpad edema. Therefore, we prepared a nano-TiO2 ointment and observed similar deswelling effects. In conclusion, nano-TiO2 might act as a novel deswelling agent related with its degradation of NO, which will aid in our ability to design effective interventions for edema involved diseases.

  10. Boron nitride nano-structures produced by pulsed laser ablation in acetone

    NASA Astrophysics Data System (ADS)

    Nistor, L. C.; Epurescu, G.; Dinescu, M.; Dinescu, G.

    2010-11-01

    Different phases of boron nitride (BN) nano-structures are synthesized from an hBN ceramic target immersed in acetone, by ablation with a high power pulsed Nd: YAG laser. Transmission electron microscopy (TEM) and electron diffraction (ED) are used to identify the morphology and structure of the prepared colloidal suspensions. It is revealed that by varying solely a single experimental parameter, i.e. the laser pulse fluency, a large variety of BN nano-structures can be produced: nanotubes, very thin graphene-like foils, nano-curls and nano-particles, all with the hexagonal graphite-like hBN structure, as well as high pressure BN phases: orthorhombic explosion E-BN nano-rods, or cubic diamond-like cBN nano-particles.

  11. In situ nano-compression testing of irradiated copper

    PubMed Central

    Kiener, D.; Hosemann, P.; Maloy, S. A.; Minor, A. M.

    2011-01-01

    Increasing demand for energy and reduction of CO2 emissions has revived interest in nuclear energy. Designing materials for radiation environments necessitates fundamental understanding of how radiation-induced defects alter mechanical properties. Ion beams create radiation damage efficiently without material activation, but their limited penetration depth requires small-scale testing. However, strength measurements of nano-scale irradiated specimens have not been previously performed. Here we show that yield strengths approaching macroscopic values are measured from irradiated ~400 nm diameter copper specimens. Quantitative in situ nano-compression testing in a transmission electron microscope reveals that the strength of larger samples is controlled by dislocation-irradiation defect interactions, yielding size-independent strengths. Below ~400 nm, size-dependent strength results from dislocation source limitation. This transition length-scale should be universal, but depend on material and irradiation conditions. We conclude that for irradiated copper, and presumably related materials, nano-scale in situ testing can determine bulk-like yield strengths and simultaneously identify deformation mechanisms. PMID:21706011

  12. Nano-modification to improve the ductility of cementitious composites

    SciTech Connect

    Yeşilmen, Seda; Al-Najjar, Yazin; Balav, Mohammad Hatam; Şahmaran, Mustafa; Yıldırım, Gürkan; Lachemi, Mohamed

    2015-10-15

    Effect of nano-sized mineral additions on ductility of engineered cementitious composites (ECC) containing high volumes of fly ash was investigated at different hydration degrees. Various properties of ECC mixtures with different mineral additions were compared in terms of microstructural properties of matrix, fiber-matrix interface, and fiber surface to assess improvements in ductility. Microstructural characterization was made by measuring pore size distributions through mercury intrusion porosimetry (MIP). Hydration characteristics were assessed using thermogravimetric analysis/differential thermal analysis (TGA/DTA), and fiber-matrix interface and fiber surface characteristics were assessed using scanning electron microscopy (SEM) through a period of 90 days. Moreover, compressive and flexural strength developments were monitored for the same period. Test results confirmed that mineral additions could significantly improve both flexural strength and ductility of ECC, especially at early ages. Cheaper Nano-CaCO{sub 3} was more effective compared to nano-silica. However, the crystal structure of CaCO{sub 3} played a very important role in the range of expected improvements.

  13. Hierarchical ferroelectric and ferrotoroidic polarizations coexistent in nano-metamaterials

    NASA Astrophysics Data System (ADS)

    Shimada, Takahiro; Lich, Le Van; Nagano, Koyo; Wang, Jie; Kitamura, Takayuki

    2015-10-01

    Tailoring materials to obtain unique, or significantly enhanced material properties through rationally designed structures rather than chemical constituents is principle of metamaterial concept, which leads to the realization of remarkable optical and mechanical properties. Inspired by the recent progress in electromagnetic and mechanical metamaterials, here we introduce the concept of ferroelectric nano-metamaterials, and demonstrate through an experiment in silico with hierarchical nanostructures of ferroelectrics using sophisticated real-space phase-field techniques. This new concept enables variety of unusual and complex yet controllable domain patterns to be achieved, where the coexistence between hierarchical ferroelectric and ferrotoroidic polarizations establishes a new benchmark for exploration of complexity in spontaneous polarization ordering. The concept opens a novel route to effectively tailor domain configurations through the control of internal structure, facilitating access to stabilization and control of complex domain patterns that provide high potential for novel functionalities. A key design parameter to achieve such complex patterns is explored based on the parity of junctions that connect constituent nanostructures. We further highlight the variety of additional functionalities that are potentially obtained from ferroelectric nano-metamaterials, and provide promising perspectives for novel multifunctional devices. This study proposes an entirely new discipline of ferroelectric nano-metamaterials, further driving advances in metamaterials research.

  14. Nano-sized crystalline drug production by milling technology.

    PubMed

    Moribe, Kunikazu; Ueda, Keisuke; Limwikrant, Waree; Higashi, Kenjirou; Yamamoto, Keiji

    2013-01-01

    Nano-formulation of poorly water-soluble drugs has been developed to enhance drug dissolution. In this review, we introduce nano-milling technology described in recently published papers. Factors affecting the size of drug crystals are compared based on the preparation methods and drug and excipient types. A top-down approach using the comminution process is a method conventionally used to prepare crystalline drug nanoparticles. Wet milling using media is well studied and several wet-milled drug formulations are now on the market. Several trials on drug nanosuspension preparation using different apparatuses, materials, and conditions have been reported. Wet milling using a high-pressure homogenizer is another alternative to preparing production-scale drug nanosuspensions. Dry milling is a simple method of preparing a solid-state drug nano-formulation. The effect of size on the dissolution of a drug from nanoparticles is an area of fundamental research, but it is sometimes incorrectly evaluated. Here, we discuss evaluation procedures and the associated problems. Lastly, the importance of quality control, process optimization, and physicochemical characterization are briefly discussed.

  15. 3D Oxidized Graphene Frameworks for Efficient Nano Sieving

    NASA Astrophysics Data System (ADS)

    Pawar, Pranav Bhagwan; Saxena, Sumit; Badhe, Dhanashree Kamlesh; Chaudhary, Raghvendra Pratap; Shukla, Shobha

    2016-02-01

    The small size of Na+ and Cl‑ ions provides a bottleneck in desalination and is a challenge in providing alternatives for continuously depleting fresh water resources. Graphene by virtue of its structural properties has the potential to address this issue. Studies have indicated that use of monolayer graphene can be used to filter micro volumes of saline solution. Unfortunately it is extremely difficult, resource intensive and almost impractical with current technology to fabricate operational devices using mono-layered graphene. Nevertheless, graphene based devices still hold the key to solve this problem due to its nano-sieving ability. Here we report synthesis of oxidized graphene frameworks and demonstrate a functional device to desalinate and purify seawater from contaminants including Na+ and Cl‑ ions, dyes and other microbial pollutants. Micro-channels in these frameworks help in immobilizing larger suspended solids including bacteria, while nano-sieving through graphene enables the removal of dissolved ions (e.g. Cl‑). Nano-sieving incorporated with larger frameworks has been used in filtering Na+ and Cl‑ ions in functional devices.

  16. Remote nano-optical beam focusing lens by illusion optics

    NASA Astrophysics Data System (ADS)

    Margousi, David; Shoorian, Hamed Reza

    2014-08-01

    In this paper, as a new application of illusion optics, a nano-optical plasmonic focusing lens structure is proposed to manipulate the light remotely by employing illusion optics theory. Plasmonic nano-optic lenses that enable super-focusing beyond the diffraction limit have been proposed as an alternative to the conventional dielectric-based refractive lenses. In the presence of an illusion device, the electromagnetic plane-waves can penetrate into a metal layer and a clear focus appears. When the illusion device is removed, waves are blocked to transmit through the metal wall. In comparison with conventional methods, our proposed method avoids any physical changes or damages in the original structure. The proposed structure can be realized by isotropic layered materials, using effective medium theory. The special feature of the proposed structure and the device concepts introduced in this work gives it an opportunity to be used as a flexible element in ultrahigh nano-scale integrated circuits for miniaturization and tuning purposes.

  17. Nano-imprint gold grating as refractive index sensor

    NASA Astrophysics Data System (ADS)

    Kumari, Sudha; Mohapatra, Saswat; Moirangthem, Rakesh S.

    2016-05-01

    Large scale of fabrication of plasmonic nanostructures has been a challenging task due to time consuming process and requirement of expensive nanofabrication tools such as electron beam lithography system, focused ion beam system, and extreme UV photolithography system. Here, we present a cost-effective fabrication technique so called soft nanoimprinting to fabricate nanostructures on the larger sample area. In our fabrication process, a commercially available optical DVD disc was used as a template which was imprinted on a polymer glass substrate to prepare 1D polymer nano-grating. A homemade nanoimprinting setup was used in this fabrication process. Further, a label-free refractive index sensor was developed by utilizing the properties of surface plasmon resonance (SPR) of a gold coated 1D polymer nano-grating. Refractive index sensing was tested by exposing different solutions of glycerol-water mixture on the surface of gold nano-grating. The calculated bulk refractive index sensitivity was found to be 751nm/RIU. We believed that our proposed SPR sensor could be a promising candidate for developing low-cost refractive index sensor with high sensitivity on a large scale.

  18. Nano Mapper: an Internet knowledge mapping system for nanotechnology development

    PubMed Central

    Hu, Daning; Dang, Yan; Chen, Hsinchun; Roco, Mihail C.; Larson, Catherine A.; Chan, Joyce

    2008-01-01

    Nanotechnology research has experienced rapid growth in recent years. Advances in information technology enable efficient investigation of publications, their contents, and relationships for large sets of nanotechnology-related documents in order to assess the status of the field. This paper presents the development of a new knowledge mapping system, called Nano Mapper (http://nanomapper.eller.arizona.edu), which integrates the analysis of nanotechnology patents and research grants into a Web-based platform. The Nano Mapper system currently contains nanotechnology-related patents for 1976–2006 from the United States Patent and Trademark Office (USPTO), European Patent Office (EPO), and Japan Patent Office (JPO), as well as grant documents from the U.S. National Science Foundation (NSF) for the same time period. The system provides complex search functionalities, and makes available a set of analysis and visualization tools (statistics, trend graphs, citation networks, and content maps) that can be applied to different levels of analytical units (countries, institutions, technical fields) and for different time intervals. The paper shows important nanotechnology patenting activities at USPTO for 2005–2006 identified through the Nano Mapper system. PMID:21170121

  19. Pulse electrochemical meso/micro/nano ultraprecision machining technology.

    PubMed

    Lee, Jeong Min; Kim, Young Bin; Park, Jeong Woo

    2013-11-01

    This study demonstrated meso/micro/nano-ultraprecision machining through electrochemical reactions using intermittent DC pulses. The experiment focused on two machining methods: (1) pulse electrochemical polishing (PECP) of stainless steel, and (2) pulse electrochemical nano-patterning (PECNP) on a silicon (Si) surface, using atomic force microscopy (AFM) for fabrication. The dissolution reaction at the stainless steel surface following PECP produced a very clean, smooth workpiece. The advantages of the PECP process included improvements in corrosion resistance, deburring of the sample surface, and removal of hydrogen from the stainless steel surface as verified by time-of-flight secondary-ion mass spectrometry (TOF-SIMS). In PECNP, the electrochemical reaction generated within water molecules produced nanoscale oxide textures on a Si surface. Scanning probe microscopy (SPM) was used to evaluate nanoscale-pattern processing on a Si wafer surface produced by AFM-PECNP For both processes using pulse electrochemical reactions, three-dimensional (3-D) measurements and AFM were used to investigate the changes on the machined surfaces. Preliminary results indicated the potential for advancing surface polishing techniques and localized micro/nano-texturing technology using PECP and PECNP processes.

  20. Exploring packaging strategies of nano-embedded thermoelectric generators

    NASA Astrophysics Data System (ADS)

    Singha, Aniket; Mahanti, Subhendra D.; Muralidharan, Bhaskaran

    2015-10-01

    Embedding nanostructures within a bulk matrix is an important practical approach towards the electronic engineering of high performance thermoelectric systems. For power generation applications, it ideally combines the efficiency benefit offered by low dimensional systems along with the high power output advantage offered by bulk systems. In this work, we uncover a few crucial details about how to embed nanowires and nanoflakes in a bulk matrix so that an overall advantage over pure bulk may be achieved. First and foremost, we point out that a performance degradation with respect to bulk is inevitable as the nanostructure transitions to a multi moded one. It is then shown that a nano embedded system of suitable cross-section offers a power density advantage over a wide range of efficiencies at higher packing fractions, and this range gradually narrows down to the high efficiency regime, as the packing fraction is reduced. Finally, we introduce a metric - the advantage factor, to elucidate quantitatively, the enhancement in the power density offered via nano-embedding at a given efficiency. In the end, we explore the maximum effective width of nano-embedding which serves as a reference in designing generators in the efficiency range of interest.