On The Effect Of Hydrodynamic Slip On The Polarization Of A Nonconducting Spherical Particle In An Alternating Electric Field,
2010
University of Nevada, Las Vegas
On The Effect Of Hydrodynamic Slip On The Polarization Of A Nonconducting Spherical Particle In An Alternating Electric Field, Hui Zhao
Mechanical Engineering Faculty Publications
The polarization of a charged, dielectric, spherical particle with a hydrodynamically slipping surface under the influence of a uniform alternating electric field is studied by solving the standard model (the Poisson–Nernst–Planck equations). The dipole moment characterizing the strength of the polarization is computed as a function of the double layer thickness, the electric field frequency, the particle’s surface charge, and the slip length. Our studies reveal that two processes contribute to the dipole moment: ion transport inside the double layer driven by the electric field and the particle’s electrophoretic motion. The hydrodynamic slip will simultaneously impact both processes. In the …
Sorption Of Bovine Serum Albumin On Nano And Bulk Oxide Particles,
2010
University of Massachusetts Amherst
Sorption Of Bovine Serum Albumin On Nano And Bulk Oxide Particles, Lei Song
Masters Theses 1911 - February 2014
Manufactured oxide nanoparticles (NPs) have large production and widespread applications, which will inevitably enter the environment. NPs can interact with proteins in living beings due to the fact that NPs can transport into blood or across cell membranes into cells. Conformational change of protein molecules after sorption on oxide NPs has been reported. Therefore, it is important to understand the adsorption mechanism of protein onto oxide NPs surfaces. Although few works have reported protein adsorption behaviors, a general systematic comparison of the effects of particle size and surface groups on protein adsorption by widely studied NPs still needs to be …
Far-Field Optical Nanoscopy Based On Continuous Wave Laser Stimulated Emission Depletion,
2010
University of South Carolina - Columbia
Far-Field Optical Nanoscopy Based On Continuous Wave Laser Stimulated Emission Depletion, C. Kuang, Wei Zhao, Guiren Wang
Faculty Publications
Stimulated emission depletion (STED) microscopy is one of the breakthrough technologies that belong to far-field optical microscopy and can achieve nanoscale spatial resolution. We demonstrate a far-field optical nanoscopy based on continuous wave lasers with different wavelengths, i.e., violet and green lasers for excitation and STED, respectively. Fluorescent dyes Coumarin 102 and Atto 390 are used for validating the depletion efficiency. Fluorescent nanoparticles are selected for characterizing the spatial resolution of the STED system. Linear scanning of the laser beams of the STED system along one line of a microscope slide, which is coated with the nanoparticles, indicates that a …
Oscillatory And Monotonic Modes Of Long-Wave Marangoni Convection In A Thin Film,
2010
Institute of Continuous Media Mechanics
Oscillatory And Monotonic Modes Of Long-Wave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Mathematics Faculty Publications
We study long-wave Marangoni convection in a layer heated from below. Using the scaling k=O Bi, where k is the wave number and Bi is the Biot number, we derive a set of amplitude equations. Analysis of this set shows presence of monotonic and oscillatory modes of instability. Oscillatory mode has not been previously found for such direction of heating. Studies of weakly nonlinear dynamics demonstrate that stable steady and oscillatory patterns can be found near the stability threshold.
Oscillatory And Monotonic Modes Of Long-Wave Marangoni Convection In A Thin Film,
2010
Western Kentucky University
Oscillatory And Monotonic Modes Of Long-Wave Marangoni Convection In A Thin Film, Sergey Shklyaev, Mikhail Khenner, Alexei Alabuzhev
Mathematics Faculty Publications
We study long-wave Marangoni convection in a layer heated from below. Using the scaling k=O Bi, where k is the wave number and Bi is the Biot number, we derive a set of amplitude equations. Analysis of this set shows presence of monotonic and oscillatory modes of instability. Oscillatory mode has not been previously found for such direction of heating. Studies of weakly nonlinear dynamics demonstrate that stable steady and oscillatory patterns can be found near the stability threshold.
Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications,
2010
University of Pennsylvania
Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza
Departmental Papers (ESE)
This paper reports on the design and experimental verification of a new class of thin-film (250 nm) superhigh- frequency laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions to excite a contourextensional mode of vibration in nanofeatures of an ultra-thin (250 nm) AlN film. In this first demonstration, 2-port resonators vibrating up to 4.5 GHz have been fabricated on the same die and attained electromechanical coupling, kt^2, in excess of 1.5%. These devices are employed to …
Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons,
2010
Technological University Dublin
Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, Sourabhi Debnath
Doctoral
Single-walled carbon nanotubes (SWCNTS) are proposed to be one of the most promising nanomaterials, with unique electronic and mechanical properties which lend themselves to a variety of applications. In all cases the quality of the SWCNT material is important, and for some applications it is paramount. Despite sustained efforts, all currently known SWCNT synthetic techniques generate significant quantities of impurities. They also grow in bundles or ropes and are largely insoluble in common organic solvents. SWCNTS can have a range of structures and their electronic properties (metallic or semiconducting) depend on their structure and as well on their diameters. Currently …
Quantum Approach To Electronic Noise Calculations In The Presence Of Electron-Phonon Interactions,
2010
Purdue University
Quantum Approach To Electronic Noise Calculations In The Presence Of Electron-Phonon Interactions, Hong-Hyun Park, Gerhard Klimeck
Birck and NCN Publications
A quantum-mechanical approach to the calculation of electronic noise for nanoscale devices is presented. This method is based on the nonequilibrium Green’s-function formalism with electron-phonon scattering mechanisms and takes the effects of the Pauli exclusion principle and the long-range Coulomb interactions into account. As examples the drain current noise characteristics of silicon nanowire transistors at room temperature are simulated. The drain current noise in the saturation regime is primarily shot-noise dominant but is suppressed for higher gate biases due to the electron-electron correlation in the channel region. The role of electron-phonon interactions on noise, the transition from thermal to shot …
Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective,
2010
Purdue University - Main Campus
Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, Pradeep R. Nair, Muhammad A. Alam
Birck and NCN Publications
Modern label-free biosensors are generally far more sensitive and require orders of magnitude less incubation time compared to their classical counterparts. However, a more important characteristic regarding the viability of this technology for applications in Genomics/Proteomics is defined by the ‘Selectivity’, i.e., the ability to concurrently and uniquely detect multiple target biomolecules in the presence of interfering species. Currently, there is no theory of Selectivity that allows optimization of competing factors and there are few experiments to probe this problem systematically. In this article, we use the elementary considerations of surface exclusion, diffusion limited transport, and void distribution function to …
Weighted Matrix Ordering And Parallel Banded Preconditioners For Iterative Linear System Solvers,
2010
Purdue University - Main Campus
Weighted Matrix Ordering And Parallel Banded Preconditioners For Iterative Linear System Solvers, Murat Manguoglu, Mehmet Koyuturk, Ahmed Sameh, Ananth Y. Grama
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
The emergence of multicore architectures and highly scalable platforms motivates the development of novel algorithms and techniques that emphasize concurrency and are tolerant of deep memory hierarchies, as opposed to minimizing raw FLOP counts. While direct solvers are reliable, they are often slow and memory-intensive for large problems. Iterative solvers, on the other hand, are more efficient but, in the absence of robust preconditioners, lack reliability. While preconditioners based on incomplete factorizations ( whenever they exist) are effective for many problems, their parallel scalability is generally limited. In this paper, we advocate the use of banded preconditioners instead and introduce …
On Landauer Versus Boltzmann And Full Band Versus Effective Mass Evaluation Of Thermoelectric Transport Coefficients,
2010
Electrical and Computer Engineering, Purdue University
On Landauer Versus Boltzmann And Full Band Versus Effective Mass Evaluation Of Thermoelectric Transport Coefficients, Changwook Jeong, Raseong Kim, Mathieu Luisier, Supriyo Datta, Mark S. Lundstrom
Birck and NCN Publications
Using a full band description of electronic bandstructure, the Landauer approach to diffusive transport is mathematically related to the solution of the Boltzmann transport equation, and expressions for the thermoelectric parameters in both formalisms are presented. Quantum mechanical and semiclassical techniques to obtain from a full description of the bandstructure, E(k), the density of modes in the Landauer approach or the transport distribution in the Boltzmann solution are compared and thermoelectric transport coefficients are evaluated. Several example calculations for representative bulk materials are presented and the full band results are related to the more common effective mass formalism. Finally, given …
Molecular Modulation Of Schottky Barrier Height In Metal-Molecule-Silicon Diodes: Capacitance And Simulation Results,
2010
Purdue University - Main Campus
Molecular Modulation Of Schottky Barrier Height In Metal-Molecule-Silicon Diodes: Capacitance And Simulation Results, Adina Scott, Chad Risko, Nicholas Valley, Mark A. Ratner, David B. Janes
Birck and NCN Publications
There is considerable current interest in using molecular materials to influence the surface potential of semiconductor devices for nanoelectronic and sensing applications. We present experimental capacitance-voltage results showing that systematic Schottky barrier height modulation can be achieved using dipolar molecular layers in gold-molecule-silicon devices. A computational methodology that combines quantum chemistry and traditional electrostatic calculations is used to explore various physical effects that can influence barrier heights in such systems. Nonidealities such as silicon surface states can influence both the potential profile within the device and the validity of the extracted barrier height. Our devices exhibit low surface state densities, …
Accurate Force Spectroscopy In Tapping Mode Atomic Force Microscopy In Liquids,
2010
Purdue University
Accurate Force Spectroscopy In Tapping Mode Atomic Force Microscopy In Liquids, Xin Xu, John Melcher, Arvind Raman
Birck and NCN Publications
Existing force spectroscopy methods in tapping mode atomic force microscopy (AFM) such as higher harmonic inversion [M. Stark, R. W. Stark, W. M. Heckl, and R. Guckenberger, Proc. Natl. Acad. Sci. U. S. A. 99, 8473 (2002)] or scanning probe acceleration microscopy [J. Legleiter, M. Park, B. Cusick, and T. Kowalewski, Proc. Natl. Acad. Sci. U. S. A. 103, 4813 (2006)] or integral relations [M. Lee and W. Jhe, Phys. Rev. Lett. 97, 036104 (2006); S. Hu and A. Raman, Nanotechnology 19, 375704 (2008); H. Holscher, Appl. Phys. Lett. 89, 123109 (2006); A. J. Katan, Nanotechnology 20, 165703 (2009)] require …
Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques,
2010
Purdue University - Main Campus
Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, Hasan Metin Aktulga, Shailaja Pandit, Adri C. T. Van Duin, Ananth Y. Grama
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
Modeling atomic and molecular systems requires computation-intensive quantum mechanical methods such as, but not limited to, density functional theory (DFT) [11]. These methods have been successful in predicting various properties of chemical systems at atomistic detail. Due to the inherent nonlocality of quantum mechanics, the scalability of these methods ranges from O(N3) to O(N7) depending on the method used and approximations involved. This significantly limits the size of simulated systems to a few thousands of atoms, even on large scale parallel platforms. On the other hand, classical approximations of quantum systems, although computationally (relatively) easy to implement, yield simpler models …
Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators,
2010
Purdue University - Main Campus
Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators, Ajit K. Vallabhaneni, Jeffrey F. Rhoads, Xiulin Ruan, Jayathi Y. Murthy
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
This work examines the quality factors (Q factors) of resonance associated with the axial and transverse vibrations of single-wall carbon nanotube (SWCNT) resonators through the use of molecular dynamics (MD) simulation. Specifically, the work investigates the effect of device length, diameter, and chirality, as well as temperature, on the resonant frequency and quality factor of these devices, and benchmarks the results of MD simulation against classical theories of energy dissipation. Of note are the facts that the quality factors associated with transverse vibration decrease with increasing device diameter and are largely insensitive to chirality. Additionally, quality factors increase with increasing …
Real-Time Monitoring Of Contact Behaviour Of Rf Mems Switches With A Very Low Power Cmos Capactive Sensor Interface,
2010
Purdue University - Main Campus
Real-Time Monitoring Of Contact Behaviour Of Rf Mems Switches With A Very Low Power Cmos Capactive Sensor Interface, Adam Fruehling, Mohammad Abu Khater, Byunghoo Jung, Dimitrios Peroulis
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
This paper presents the first ultra-low power, fully electronic methodology for real-time monitoring of the dynamic behavior of RF MEMS switches. The measurement is based on a capacitive readout circuit composed of 67 transistors with 105 µm x 105 µm footprint consuming as little as 60 µW. This is achieved by accurately sensing the capacitance change around the contact region at sampling rates from 10 kHz to 5 MHz. Experimental and simulation results show that times of not only the first contact event but also all subsequent contact bounces can be accurately measured with this technique without interfering with the …
A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors,
2010
Purdue University - Main Campus
A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors, Hao-Han Hsu, Dimitrios Peroulis
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
In this paper we present, for the ¯rst time, an experimentally-extracted model for the spring con- stant and tuning range of an analog RF-MEMS var- actor that includes viscoelastic e®ects in RF-MEMS devices. By utilizing a bi-state bias condition with one state lasting 60 minutes and the other 1 minute, this model focuses on capturing the true electrome- chanical behavior of the varactor. An experimental setup with very high long-term accuracy is created to measure capacitance of the varactor up to 1,370 hours. The impact of these e®ects and the e®ective- ness of the model are demonstrated on a tunable- …
Giant Raman Enhancement On Nanoporous Gold Film By Conjugating With Nanoparticles For Single-Molecule Detection,
2010
University of Nevada, Las Vegas
Giant Raman Enhancement On Nanoporous Gold Film By Conjugating With Nanoparticles For Single-Molecule Detection, Lihua Qian, Biswajit Das, Yan Li, Zhilin Yang
Electrical and Computer Engineering Faculty Publications
Hot spots have the contradictively geometrical requirements for both the narrowest interstices to provide strong near-field coupling, and sufficient space to allow entrance of the analytes. Herein, a two-step method is employed to create hot spots within hybrid nanostructures, which consist of self-supported nanoporous gold films with the absorbed probes and subsequent nanoparticle conjugates without surface agents or mechanical motion. The molecules confined into 1 nm interstice exhibit 2.9 × 107 times enhancement in Raman scattering compared to pure nanoporous gold. Giant enhancement primarily results from strong near-field coupling between nanopore and nanoparticle, which is theoretically confirmed by finite-difference …
Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes,
2010
College of William & Mary - Arts & Sciences
Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes, Joshua Erold Robert Abelard
Dissertations, Theses, and Masters Projects
No abstract provided.
Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel,
2010
Old Dominion University
Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel, Ye Ai, Shizhi Qian, Sheng Liu, Sang W. Joo
Mechanical & Aerospace Engineering Faculty Publications
Experiments show that particles smaller than the throat size of converging-diverging microchannels can sometimes be trapped near the throat. This critical phenomenon is associated with the negative dc dielectrophoresis arising from nonuniform electric fields in the microchannels. A finite-element model, accounting for the particle-fluid-electric field interactions, is employed to investigate the conditions for this dielectrophoretic (DEP) choking in a converging-diverging microchannel for the first time. It is shown quantitatively that the DEP choking occurs for high nonuniformity of electric fields, high ratio of particle size to throat size, and high ratio of particle's zeta potential to that of microchannel. © …
