bluuebunny/crossref_metadata_2025_split huggingface dataset:
Developments of Extra-High Purity Stainless Steels for Nuclear Corrosive Environments
Authors: Nakayama Junpei , Kiuchi Kiyoshi 
Published: April 2011

ABSTRACTThe austenitic stainless steels so-called, the EHP steels with the extra high purity, are developed for improving the reliability of nuclear equipments materials used in the heavily corrosive irradiation environments. By considering the impurities segregation mechanism, the major impurities included in the EHP steels is controlled less than 100ppm by the new melting technology. It is two-step refining process composed of CCIM and EB for effectively removing both non-volatile and volatile harmful elements. The risk to cracking on melting and welding processes is also effectively minimized by enhancing both the eutectic point and the metallic bonding at grain-boundaries. In the EHP steels, it is possible to select the appropriate composition of Ni and Cr for stabilizing austenitic phase and enhancing corrosion resistance. The characteristics of the welding joints are as good as those of the base metal because the same filler metal is sed without the formation of residual delta ferrite. The resistance to IGC and SCC of the EHP steels is markedly improved by minimizing the refining effects, except for type 316 steels with Mo. The welding technique and the chemical composition range are selected for standardizing the EHP.
NanoLAB Triboprobe: Characterizing Dynamic Wear, Friction and Fatigue at the Nanoscale
Authors: Lockwood A J , Wedekind J , Gay R S , Wang J J , Bobji M S , Amavasai B , Howarth M , Möbus G , Inkson B J 
Published: April 2011

ABSTRACTIn-situ transmission electron microscopy (TEM) has developed rapidly over the last decade. In particular, with the inclusion of scanning probes in TEM holders, allows both mechanical and electrical testing to be performed whilst simultaneously imaging the microstructure at high resolution. In-situ TEM nanoindentation and tensile experiments require only an axial displacement perpendicular to the test surface. However, here, through the development of a novel in-situ TEM triboprobe, other surface characterisation experiments are now possible, with the introduction of a fully programmable 3D positioning system.Programmable lateral displacement control allows scratch tests to be performed at high resolution with simultaneous imaging of the changing microstructure. With the addition of repeated cyclic movements, both nanoscale fatigue and friction experiments can also now be performed. We demonstrate a range of movement profiles for a variety of applications, in particular, lateral sliding wear.The developed NanoLAB TEM triboprobe also includes a new closed loop vision control system for intuitive control during positioning and alignment. It includes an automated online calibration to ensure that the fine piezotube is controlled accurately throughout any type of test. Both the 3D programmability and the closed loop vision feedback system are demonstrated here.
Atomistic study of the mechanical stability of multi-layered graphene nanobridges
Authors: Nakajima T. , Shintani K. 
Published: April 2011

ABSTRACTThe stability of elongated single- and multi-layered graphene nanoribbons (GNRs) are investigated by molecular-dynamics simulation. In order that GNRs are to be modeled as nanobridges connecting two terminals of electronic devices, the short edges of the GNRs are constrained. The distances between the two constrained edges are gradually increased, and the GNRs are uniaxially strained. The energies and out-of-plane deformations of such uniaxially strained GNRs are examined. The energies of multi-layered GNRs will be lower than those of isolated GNRs because the surface areas of multi-layered GNRs are smaller than the total area of the isolated GNRs. Understanding the relationship between the out-of-plane deformations and strain will lead to the control of the ripple structures of GNRs.
Current Density Dependence of Transient Electroluminescence in
Phosphorescent Organic Light-Emitting Diodes
Authors: Kajii Hirotake , Takahota Noriyoshi , Wang Yadong , Ohmori Yutaka 
Published: April 2011

ABSTRACTThe transient electroluminescence (EL) of phosphorescent organic
light-emitting diodes (OLEDs) was investigated. The behaviors of the
transient characteristics are analyzed using the triplet-triplet
annihilation model. The device exhibited a gradual decrease in quantum
current efficiency owing to the triplet-triplet annihilation at a high
current density. At a higher current density, the reduced rise and decay
times are due to high-density triplet excitons related to the enhanced
triplet-triplet annihilation and the increase of the nonradiative process.
The modulation speed of the devices is mainly limited by the phosphorescent
recombination lifetime.
Incubation Time Free CVD-TiO2 Film Preparation Using Novel Precursor of Ti-DOT
Authors: Chiba Hirokazu , Tada Ken-ichi , Yamamoto Toshiki , Iwanaga Kohei , Maniwa Atsushi , Yotsuya Tadahiro , Oshima Noriaki , Funakubo Hiroshi 
Published: April 2011

ABSTRACTTitanium oxide thin films were deposited at 250 – 400 °C on amorphous SiO2 prepared on n-type Si substrates by chemical vapor deposition (CVD) using a novel precursor, ethene-1,2-diylbis(tert-butylaminido)diisopropoxotitanium [Ti[N(tBu)C=CN(tBu)](OiPr)2 , Ti-DOT], with oxygen gas as an oxidant. Deposition characteristics of thin films were compared with those using titanium tetraisopropoxide [Ti(OiPr)4, TTIP]. As a result, the deposition amount of TiO2 thin films using Ti-DOT was larger than that of TTIP because of the shorter incubation time in the case of Ti-DOT. Smaller surface roughness was observed for the films using Ti-DOT. In addition, a good conformability was obtained on amorphous SiO2 hole prepared on n-type Si substrate substrate with aspect ratio of 5.
Correlation between Adhesion Strength and Thin film/Substrate Mechanical Properties using the Nano-Scratch Technique
Authors: Zhou Bo , Randall Nicholas , Prorok Barton 
Published: April 2011

ABSTRACTScratch testing, as a mature technique for coating adhesion quantification, has been widely adopted by both industrial and academic fields in recent years. Following the urgent needs of very small materials characterization, nano-scratch testing has gradually replaced the traditional pull-off test for the study of ultra-thin film properties. In this research, the relationship between the adhesion strength and film/substrate mechanical properties was investigated to provide fundamental but crucial knowledge of the scratch mechanism. Scratch tests were performed on different film/substrate combinations using a Nano Scratch Tester with a sphero-conical diamond indenter. A progressive load mode was employed to cause coating failure during scratch on the film surface. The critical values of different failure mechanisms, such as cracking and delamination were accurately determined according to the scratch panorama image, penetration and residual depth data. In addition, the hardness (H) and modulus (E) values of the thin films and substrates were measured with an Ultra Nanoindentation Tester. The scratch critical failure loads were then plotted versus film/substrate H and E ratios. A unique relationship was found between these parameters that could help understand the true mechanism behind scratch adhesion and leverage this methodology to a new theoretical level.
Synthetic control over the structure and symmetry of carbon nanotubes: Towards biomedical applications
Authors: Lowry Michael S. , Rayms-Keller Alfredo , Long Karen J. , Santiago Francisco , Gehman Victor H. , Boulais Kevin A. 
Published: April 2011

ABSTRACTCarbon nanotubes (CNTs) are appealing materials for biomedical applications due to their unique chemical, electrical and mechanical properties. The emphasis of the present work is on controlling the structure and symmetry of carbon nanotubes by imposing an applied stress at the CNT growth site. CNTs were grown under these conditions using standard chemical vapor deposition (CVD) techniques and were subsequently characterized with a scanning electron microscope; the methodology and implications of this approach are discussed herein.
Nanoscale deformation of MEMS materials
Authors: Lockwood A J , Padmanabhan A , Bunyan R J T , Inkson B J 
Published: April 2011

ABSTRACTUsing a novel in-situ TEM triboprobe holder, nanoscale structures formed from polysilicon MEMS materials have been loaded to characterise the failure mechanisms of reduced scale components. Nanobridges with cross-section dimensions much less than 1μm have been deformed using both single, high displacement indentation and low displacement cyclic fatigue. In both deformation modes, significant residual plastic deformation is measured, occurring and accumulating in the polysilicon. This can be seen as a gradual curvature along the entire crossbeam upon unloading. Where the radius of curvature is very high, fracture of the beams at the centre point was generally also seen. When loading at much lower displacement but under fatigue conditions, localised heating around the moving contact point initiates carbon migration, forming a very strong bond. A high tensile force was needed to severe the contact during unload. Such in-situ techniques demonstrate a range of time dependant failure modes which can be overlooked using post-mortem analysis. In particular, the combined effect of localised frictional heating and contamination on the reliability of components that repeatedly comes into contact with one another.
Pressure-Induced Nano-Crystallization of Y2O3
Authors: Deutsch Stuart , Al-Sharab Jafar F. , Kear Bernard H. , Tse Stephen D. 
Published: April 2011

ABSTRACTA reversible-phase transformation process to convert coarse-grained polycrystalline cubic-Y2O3 directly into the nanocrystalline state is being developed. The process involves a forward cubic-to-monoclinic phase transition under high pressure and a backward transformation from monoclinic-to-cubic under a lower pressure. The process has been used to reduce the grain size of fully dense cubic-Y2O3 from 300 μm to 0.1 μm. A surface modification effect, comprising a columnar-grained structure, has also been observed. Preliminary work indicates that the surface structure is modified, apparently formed by interaction between the graphite heater and sample.
Mechanical Behavior on Micro-compression Test in Ultra-low Carbon Steel Produced by High Pressure Torsion
Authors: Nagoshi Takashi , Shibata Akinobu , Sone Masato , Todaka Yoshikazu 
Published: April 2011

ABSTRACTMechanical behavior of ultra-fine grained (UFG) steel fabricated by high pressure torsion (HPT) was investigated by micro-sized compression test of a micro-sized pillar with uniform dimensions (non-tapered, non-filleted) carefully fabricated by FIB milling. After HPT process, grains were elongated to shear direction and its grain size was decreased down to 300 nm in diameter with increasing strain amount. Compression test confirmed that the uniform elongations of ultra-fine grained materials were lower than 3% and do not depend on the grain size.
Profiling of the Mechanical Properties of Ultralow-k Films Using Nanoindentation Techniques
Authors: Geisler Holm , Mayer Ulrich , Lehr Matthias U. , Hofmann Petra , Engelmann Hans-Juergen 
Published: April 2011

ABSTRACTSeveral nanoindentation techniques were applied to the surface, the reverse side and cross-sections of PECVD ultralow-k (ULK) film stacks to characterize their elasto-plastic properties quantitatively. Results showed good agreement of the reduced modulus (Er) values measured from above and on cross-sections, respectively. Er decreased by 10-22% from the upper to the lower surface of the films. This gradient suggests that UV light absorption inside the film leads to slightly reduced curing at the rear side of the films compared to the surface of the ULK layers. Both quasi-static nanoindentation and dynamic mechanical mapping showed this trend. It is demonstrated that quantitative mechanical mapping can be performed with a lateral resolution ≤ 100nm. Slight local variations of Er were detected on ULK/SiCxNy films stacked on top of Cu-low-k interconnect structures.
Nanometer Scale Mechanical Behavior of Grain Boundaries
Authors: Wang Chien-Kai , Chew Huck Beng , Kim Kyung-Suk 
Published: April 2011

ABSTRACTA nonlinear field projection method has been developed to study nanometer scale mechanical properties of grain boundaries in nanocrystalline FCC metals. The nonlinear field projection is based on the principle of virtual work, for virtual variations of atomic positions in equilibrium through nonlocal interatomic interactions such as EAM potential interaction, to get field-projected subatomic-resolution traction distributions on various grain boundaries. The analyses show that the field projected traction produces periodic concentrated compression sites on the grain boundary, which act as crack trapping or dislocation nucleation sites. The field projection was also used to assess the nanometer scale failure processes of Cu Σ5 grain boundaries doped with Pb. It was revealed that the Pb dopants prevented the emission of dislocations by grain boundary slip and embrittles the grain boundary.
Sharp Silicon Nano-Needles Based on Boron Etch-Stop in TMAH
Solutions
Authors: Yan Sheping , Xu Yang , Yang Junyi , Wang Huiquan , Jin Zhonghe , Wang Yuelin 
Published: April 2011

ABSTRACTOperations on biological living cells and molecular devices have driven
research towards implementation of high-aspect-ratio nano-needles. However,
current nano-needle fabrication is complicated to control the sizes and
angles. In this work, we develop a simple method to fabricate repeatable and
integrated circuit (IC)-compatible sharp silicon nano-needles based on boron
etch-stop in tetramethyl ammonium hydroxide (TMAH) solutions, and the needle
angles can be accurately controlled. An analytical model is proposed to
efficiently predict the needle sizes and explain the etching evolution of
silicon nano-needles.
Dual Detection Platform with Refractive Index and SERS Sensing
Based on Colloidal Gold Functionalized Porous Silicon
Substrates
Authors: Jiao Yang , Koktysh Dmitry S. , Weiss Sharon M. 
Published: April 2011

ABSTRACTWe demonstrate a dual-mode sensing platform based on porous silicon (PSi)
substrates coated with colloidal gold (Au) nanoparticles (NPs). This Au-PSi
composite structure supports both molecular fingerprinting via surface
enhanced Raman scattering (SERS) and quantification of molecular binding via
reflectance measurements. Reflectance shifts of 7-10 nm in the infrared
region were observed in the case of adsorbing benzenethiol or antioxidant
glutathione molecules on the surface of Au NPs. Subsequent SERS measurements
showed unique identification for both molecules and provided a < 1 μM and
< 1 mM detection resolution for benzenethiol and glutathione,
respectively.
Characterization of immobilized DNA on sulfur-passivated InAs
surfaces
Authors: Cho EunKyung , Wu Pae , Ahmed Minhaz , Brown April , Kuech T. F. 
Published: April 2011

ABSTRACTThe immobilization of DNA on passivated n-type InAs (100) surfaces has been
studied using X-ray and ultraviolet photoelectron spectroscopy. The benefits
of sulfur passivation using ammonium sulfide solution
((NH4)2S) for DNA immobilization were examined. The
XPS/UPS data carried out on non-functionalized and functionalized surfaces
demonstrate that the DNA probes reacted with the sulfur-passivated InAs
surface. The XPS data in combination with fluorescently-tagged DNA indicate
that the sulfur passivation process leads to a higher and more uniform
attachment of DNA over the surface compared to non-sulfur-passivated InAs
surfaces. The XPS data obtained immediately after sulfur passivation clearly
observes In-S bonding, with little or no As-S. In addition, the XPS spectra
of As 3d core-levels immediately after sulfur passivation shows that there
is a negligible amount of As-Ox, but the peak become considerable
after exposure to the aqueous DNA probe solution. The increase in
As-Ox is likely due to the presence of non-sulfur bonded As
atoms present on the surface. The presence of sulfur on the surface does
lead to the high areal density of attached ssDNA. This system forms the
basis of a DNA sensing system. While chemically passivating the surface
against oxidation and facilitating probe attachment, the changes in Fermi
level position were also monitored by UPS. UPS spectra show that the Fermi
level of a clean InAs surface is located ~0.6 eV above the valence band
maximum. The changes in electronic states induced by sulfur passivation and
the pinning of EF are discussed.
Chemically Functionalized Carbon Nanotube Label for
Immunoassay
Authors: Abera Adeyabeba , Choi Jin-Woo 
Published: April 2011

ABSTRACTA recent approach in disease diagnosis and viral epidemics is aimed at
point-of-care tests that could be administered near the patient rather than
time-consuming processes involving centralized laboratories. Point-of-care
devices provide rapid results in simple and low-cost manner requiring only
small sample volumes. These devices will strongly benefit from advanced
materials and fabrication methods to improve their efficiency and
sensitivity. We report a functionalized carbon nanotube label for an
immunosensor application. Carbon nanotube label was prepared by modifying
the carbon nanotube surface to anchor biomolecules. First, the carboxylic
acid treated multi-walled carbon nanotubes (MWCNTs) were uniformly dispersed
with polyvinylpyrrolidone (PVP) by sonication in aqueous solution. PVP
partially wraps around the carbon nanotubes and exposes the surface of the
nanotubes for further functionalization. The MWCNTs were then conjugated
with human immunoglobulin G (IgG) using EDC/Sulfo-NHS coupling chemistry,
where the antibodies occupied sites not covered by PVP. The dispersion,
surfactant modification, and antibody conjugation of the MWCNTs were also
confirmed using SEM and TEM images. The successful functionalization of the
MWCNTs and reactivity of the covalent attached antibodies were demonstrated
for specific antigen binding on the microelectrode device. The carbon
nanotube-based detection mechanism could be tailored for screening various
analyte specific molecules. Furthermore, the reported technique could easily
be integrated in various microfluidic and lab-on-a-chip devices for the
development of functional electronic sensors providing quantitative,
sensitive, and low-cost detection in pointof- care setup.
Label-Free, Electrical Biomarker Detection Based on Nanowire Biosensors Utilizing Antibody Mimics as Capture Probes
Authors: Chang Hsiao-Kang , Ishikawa Fumiaki , Zhou Chongwu 
Published: April 2011

ABSTRACTAntibody mimic proteins (AMPs) are poly-peptides that bind to their target analytes with high affinity and specificity, just like conventional antibodies, but are much smaller in size (2-5 nm, less than 10kDa). In this report, we describe the first application of AMP in the field of nanobiosensors. In2O3 nanowire based biosensors have been configured with an AMP (Fibronectin, Fn) to detect nucleocapsid (N) protein, a biomarker for severe acute respiratory syndrome (SARS). Using these devices, N protein was detected at sub-nanomolar concentration in the presence of 44 μM bovine serum albumin as a background. Furthermore, negative control experiment is carried out to confirm the role of AMPs in N protein detection.
Morphological evolution of large-scale vertically aligned ZnO nanowires and their photoluminescence properties by hydrogen plasma treatment
Authors: Zhong Miao , Li Yanbo , Paulsen Alexander , Tokizono Takero , Yamada Ichiro , Delaunay Jean-Jacques 
Published: April 2011

ABSTRACTIn this report, large-scale vertically aligned ZnO nanowires, with diameter around 75 nm and length around 2-5 μm, were synthesized on a-plane sapphire by a single step chemical vapor deposition method. The XRD pattern of the as-prepared sample showed a strong ZnO (0002) peak and a weak ZnO (0004) peak that indicate good orientation and high crystal quality of the ZnO nanowires. The sample was then treated by hydrogen plasma, without exhibiting obvious structural damage to the nanowires. The photoluminescence spectra of as-prepared and H2-plasma-treated samples were then examined. A strong green emission peak (centered at 520 nm) was observed in the PL spectrum of as-prepared sample. In sharp contrast, a significant increase of the near-band edge emission (centered at 380 nm) and a strong decrease of the green emission (centered at 520 nm) were found in the PL spectrum of H2-plasma-treated sample. We propose that an efficient passivation of oxygen vacancies by H atoms will cause a drastic decrease of the green emission. More important, it would lead to a significant reduction of surface depletion layer, leading to a great enlargement of total effect area for UV emission. Meanwhile, the significant enhancement of the intensity of UV emission might also attribute to the combined effects of structure-induced waveguide behavior and UV amplified spontaneous emission. It is expected that the enhanced UV emission of vertically aligned ZnO nanowires can be used to improve the performance of UV light emitting devices.
A Resistless Process for the Production of Patterned, Vertically Aligned ZnO Nanowires.
Authors: Ladanov Mikhail , Elineni Kranthi Kumar , Ram Manoj , Gallant Nathan D. , Kumar Ashok , Matthews Garrett 
Published: April 2011

ABSTRACTZnO nanostructures have attracted a great deal of interest because of their biocompatibility and outstanding optical and piezoelectric properties. Their uses are widely varying, including as the active element in sensors, solar cells, and nanogenerators. One of the major complications in device development is how to grow ZnO nanowires in well aligned and patterned films with predefined geometrical shape and aspect ratio. Controlled growth is required to achieve the optimal density of nanowires and to produce a defined geometric structure for incorporation in the device. In this work, we have presented a method by which vertically aligned ZnO nanowires could be grown in defined patterns on surfaces without the use of resists. We used a hydrothermal method to grow ZnO nanowires on a substrate through growth modifiers that was pre-patterned with a seeding solution by means of microcontact printing. This method produced vertically aligned ZnO nanowires of predefined size and shape with pattern resolution high enough for the production of rows of single nanowires. The nanowires were characterized by using scanning electron microscopy (SEM) and X-ray diffraction spectroscopy (XRD) techniques.
Novel Er-doped organic complexes for application in 1.5 μm
emitting solution-processed organic light emitting diodes
(OLEDs)
Authors: Coya Carmen , Álvarez Angel Luis , Martín Gil Jesús , Martín María , Martín Ramos Pablo , Zaldo Carlos 
Published: April 2011

ABSTRACTWe describe the fabrication and characterization of solution processed
organic light emitting diodes (OLEDs) based on novel near-infrared emitting
erbium(III) complexes, consisting of three perfluoroalkyl-β-diketone ligands
and 5-NO2-1,10-phenanthroline as chelating N,N-donor molecule.
The function of N,N molecule is to saturate the coordination sphere of the
erbium ion and to harvest excitation light that can be transferred to the
excited states of the erbium ion. The devices have been fabricated by
spin-coating, using 1 %wt methanol precursor solutions. These Er-complexes
form very uniform thin films. The OLED structure is glass/indium–tin
oxide(ITO) / poly(3,4-ethylenedioxythiophene) / poly(4-styrenesulfonate)
(PEDOT:PSS)/Er-complex/Ca/Al. The good electrical response, with low
threshold voltages (a few volts), together with the very uniform thin films
formed, made these complexes promising for IR emitting displays.