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Full-Text Articles in Physics

Correct Spectral Conversion Between Surface‐Enhanced Raman And Plasmon Resonance Scattering From Nanoparticle Dimers For Single‐Molecule Detection, Kyuwan Lee Dec 2012

Correct Spectral Conversion Between Surface‐Enhanced Raman And Plasmon Resonance Scattering From Nanoparticle Dimers For Single‐Molecule Detection, Kyuwan Lee

Kyuwan Lee

Simultaneous measurement of surface-enhanced Raman scattering (SERS) and localized surface plasmon resonance (LSPR) in nanoparticle dimers presents outstanding opportunities in molecular identification and in the elucidation of physical properties, such as the size, distance, and deformation of target species. SERS–LSPR instrumentation exists and has been used under limited conditions, but the extraction of SERS and LSPR readouts from a single measurement is still a challenge. Herein, the extraction of LSPR spectra from SERS signals is reported and a tool for measuring the interparticle distance from Raman enhancement data by the standardization of the SERS signal is proposed. The SERS nanoruler …


Modelling Three-Phase Flow In Metallurgical Processes, Christoph Goniva, Gijsbert Wierink, Kari Heiskanen, Stefan Pirker, Christoph Kloss Dec 2012

Modelling Three-Phase Flow In Metallurgical Processes, Christoph Goniva, Gijsbert Wierink, Kari Heiskanen, Stefan Pirker, Christoph Kloss

Gijsbert Wierink

The interaction between gasses, liquids, and solids plays a critical role in many processes, such as coating, granulation and the blast furnace process. In this paper we present a comprehensive numerical model for three phase flow including droplets, particles and gas. By means of a coupled Computational Fluid Dynamics (CFD) - Discrete Element Method (DEM) approach the physical core phenomena are pictured at a detailed level. Sub-models for droplet deformation, breakup and coalescence as well as droplet-particle and wet particle-particle interaction are applied. The feasibility of this model approach is demonstrated by its application to a rotating drum coater. The …


Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu Nov 2012

Nanoroughened Surfaces For Efficient Capture Of Circulating Tumor Cells Without Using Capture Antibodies, Weiqiang Chen, Shinuo Weng, Feng Zhang, Steven Allen, Xiang Li, Liwei Bao, Raymond H. W. Lam, Jill A. Macoska, Sofia D. Merajver, Jianping Fu

Weiqiang Chen

Circulating tumor cells (CTCs) detached from both primary and metastatic lesions represent a potential alternative to invasive biopsies as a source of tumor tissue for the detection, characterization and monitoring of cancers. Here we report a simple yet effective strategy for capturing CTCs without using capture antibodies. Our method uniquely utilized the differential adhesion preference of cancer cells to nanorough surfaces when compared to normal blood cells and thus did not depend on their physical size or surface protein expression, a significant advantage as compared to other existing CTC capture techniques.


Hordó Kollektor 3.0, Pal R. Molnar Sep 2012

Hordó Kollektor 3.0, Pal R. Molnar

Pal R. Molnar

Napjainkban egyre többen telepítenek napkollektorokat, a használati melegvíz ellátására, illetve fűtés rásegítésre. Ezen kollektorok hatásfoka széles határok között váltakozik.


Formalizing Mission Analysis And Design Techniques For High Altitude Ballooning, Jeremy Straub, Ronald Fevig Jun 2012

Formalizing Mission Analysis And Design Techniques For High Altitude Ballooning, Jeremy Straub, Ronald Fevig

Jeremy Straub

High altitude balloon (HAB) missions can be and are used to teach concepts related to spacecraft and satellite design. A HAB mission, however, presents unique characteristics, which must be understood and respected to produce a desirable outcome. Because of this, flying an unaltered satellite design as a HAB payload would be as undesirable as utilizing an unaltered HAB design as a satellite. A well-defined process for HAB mission design is thus needed. The process presented mirrors commonly used space mission design processes to facilitate easy transition between the two. It is also comparatively simple, due to the smaller scale of …


Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu Apr 2012

Nanotopography Influences Adhesion, Spreading, And Self-Renewal Of Human Embryonic Stem Cells, Weiqiang Chen, Luis G. Villa-Diaz, Yubing Sun, Shinuo Weng, Jin Koo Kim, Raymond H. W. Lam, Lin Han, Rong Fan, Paul H. Krebsbach, Jianping Fu

Weiqiang Chen

Human embryonic stem cells (hESCs) have great potentials for future cell-based therapeutics. However, their mechanosensitivity to biophysical signals from the cellular microenvironment is not well characterized. Here we introduced an effective microfabrication strategy for accurate control and patterning of nanoroughness on glass surfaces. Our results demonstrated that nanotopography could provide a potent regulatory signal over different hESC behaviors, including cell morphology, adhesion, proliferation, clonal expansion, and self-renewal. Our results indicated that topological sensing of hESCs might include feedback regulation involving mechanosensory integrin-mediated cell matrix adhesion, myosin II, and E-cadherin. Our results also demonstrated that cellular responses to nanotopography were cell-type …


Insights Into The Power Law Relationships That Describe Mass Deposition Rates During Electrospinning, Jonathan J. Stanger, Nick Tucker, Simon Fullick, Mathieu Sellier, Mark P. Staiger Feb 2012

Insights Into The Power Law Relationships That Describe Mass Deposition Rates During Electrospinning, Jonathan J. Stanger, Nick Tucker, Simon Fullick, Mathieu Sellier, Mark P. Staiger

Jonathan J Stanger

This work explores how in electrospinning, mass deposition rate and electric current relate to applied voltage and electrode separation, factors give a range of applied electric fields. Mass deposition rate was measured by quantifying the rate of dry fibre deposited over time. Electric current was measured using a current feedback from the high voltage supply. The deposition of fibre was observed to occur at a constant rate for deposition times of up to 30 min. Both the mass deposition rate and electric current were found to vary with the applied voltage according to a power law. The relationship between the …


Manipulation Of Electrospun Fibres In Flight: The Principle Of Superposition Of Electric Fields As A Control Method, Nurfaizey A. Hamid, Jonathan J. Stanger, Nick Tucker, Andrew Wallace, Mark P. Staiger Jan 2012

Manipulation Of Electrospun Fibres In Flight: The Principle Of Superposition Of Electric Fields As A Control Method, Nurfaizey A. Hamid, Jonathan J. Stanger, Nick Tucker, Andrew Wallace, Mark P. Staiger

Jonathan J Stanger

This study investigates the magnitude of movement of the area of deposition of electrospun fibres in response to an applied auxiliary electric field. The auxiliary field is generated by two pairs of rod electrodes positioned adjacent and parallel to the line of flight of the spun fibre. The changes in shape of the deposition area and the degree of movement of the deposition area are quantified by optical scanning and image analysis. A linear response was observed between the magnitude of movement of the deposition area and voltage difference between the auxiliary and deposition electrodes. A squeezing effect which changed …


Local Non-Equilibrium Diffusion Model For Solute Trapping During Rapid Solidification, Sergey Sobolev Jan 2012

Local Non-Equilibrium Diffusion Model For Solute Trapping During Rapid Solidification, Sergey Sobolev

Sergey Sobolev

A local non-equilibrium diffusion model (LNDM) for rapid solidification of binary alloys has been briefly reviewed and used to modify a number of solute trapping models with different solid–liquid interface kinetics. The LNDM takes into account deviation from local equilibrium of a solute diffusion field in bulk liquid on the basis that the exact solutions to hyperbolic diffusion equations govern the solute concentration and solute flux in bulk liquid under local non-equilibrium conditions. The LNDM leads to a velocity-dependent effective diffusion coefficient in bulk liquid ahead of the solid–liquid interface, which goes to zero when the interface velocity goes to …


Rapid Colloidal Solidifications Under Local Nonequilibrium Diffusion Conditions, Sergey Sobolev Jan 2012

Rapid Colloidal Solidifications Under Local Nonequilibrium Diffusion Conditions, Sergey Sobolev

Sergey Sobolev

Partition coefficient for rapid solidification of colloidal suspensions has been calculated under local nonequilibrium diffusion conditions typically used when processing advanced materials. It has been demonstrated that the local nonequilibrium diffusion effects stabilize the planar solid liquid interface and lead to an abrupt transition to diffusionless solidification with complete particle trapping. The effective diffusion coefficient, which depends on interface velocity and particle size, has been introduced. It explains the strong dependences of the partition coefficient and the velocity leading to absolute stability of a planar solid–liquid interface on particle size.


An Analytical Model For Local-Nonequilibrium Solute Trapping During Rapid Solidification, Sergey Sobolev Jan 2012

An Analytical Model For Local-Nonequilibrium Solute Trapping During Rapid Solidification, Sergey Sobolev

Sergey Sobolev

Updated version of local non-equilibrium diffusion model (LNDM) for rapid solidification of binary alloys was considered. The LNDM takes into account deviation from local equilibrium of solute concentration and solute flux fields in bulk liquid. The exact solutions for solute concentration and flux in bulk liquid were obtained using hyperbolic diffusion equations. The results show the transition from diffusion-limited to purely thermally controlled solidification with effective diffusion coefficient D →0 and complete solute trapping K(v)→1 at V→VDb for any kind of solid-liquid interface kinetics. Critical parameter for diffusionless solidification and complete solute trapping is the diffusion speed in bulk liquid …


Ogólnotechniczne Podstawy Biotechnologii Z Elementami Grafiki Inżynierskiej Ćw., Wojciech M. Budzianowski Jan 2012

Ogólnotechniczne Podstawy Biotechnologii Z Elementami Grafiki Inżynierskiej Ćw., Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.


Materiały Odstresowujące, Wojciech M. Budzianowski Jan 2012

Materiały Odstresowujące, Wojciech M. Budzianowski

Wojciech Budzianowski

No abstract provided.