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The Effects Of Scale On Granular Mixing In A Double Screw Pyrolyzer, Breanna L. Marmur
The Effects Of Scale On Granular Mixing In A Double Screw Pyrolyzer, Breanna L. Marmur
Breanna L. Marmur
Granular mixing processes are important to many industries including the pharmaceutical, agricultural, and biotechnology industries. These processes often require both a high degree of homogeneity and a high degree of customizability. As granular mixing processes are so widely employed, a thorough understanding of the mixing dynamics is necessary to understand and control the resulting products. Research into granular mixing processes has been, thus far, largely focused on laboratory scale mixers with simple geometries, while actual industrial processes often require large mixers with complex geometries. Moreover, granular mixing processes are often very sensitive to changes in operating conditions and any solutions …
A New Microfluidic Device For Complete, Continuous Separation Of Microparticles, Liang-Liang Fan, Xu-Kun He, Yu Han, Li Du, Liang Zhao, Jiang Zhe
A New Microfluidic Device For Complete, Continuous Separation Of Microparticles, Liang-Liang Fan, Xu-Kun He, Yu Han, Li Du, Liang Zhao, Jiang Zhe
Dr. Jiang Zhe
A microchannel with symmetric sharp corners is reported for particle separation, based on the inter-play between the inertial lift force and the centrifugal force induced by sharp corners. At an appropriate flow rate, the centrifugal force is larger than the inertial lift force on large particles, while the inertial lift force is dominant on small particles. Hence large particles are centrifuged to the center, while small par-ticles are focused at side streams, achieving complete particle separation. The device requires no sheath flow, avoiding the dilution of analyte sample and complex operation, and can be potentially used for many lab-on-a-chip applications.
Design Charts For Circular Fins Of Arbitrary Profile Subject To Radiation And Convection With Wall Resistances, G. Zhang, Benjamin T.F. Chung
Design Charts For Circular Fins Of Arbitrary Profile Subject To Radiation And Convection With Wall Resistances, G. Zhang, Benjamin T.F. Chung
Dr. Benjamin T.F. Chung
In this work, the optimization for a radiative-convective annular fin of arbitrary profile with base wall thermal resistances is considered. A fourth order Runge-Kutta method is used to solve the associated non-linear governing equa-tions. Further differentiations yield the optimum heat transfer and the optimum fin dimensions. To facilitate the thermal design, design charts for optimum dimensions are proposed. Furthermore, the fin effectiveness for the optimal annular ra-diative-convective fins is presented to check the practicality of the design. http://dx.doi.org/10.2174/1874396X01206010015
Novel Quantitative Macro Biomolecule Analysis Based On A Micro Coulter Counter, Y Han, H. Wu, F. Liu, Gang Cheng, Jiang Zhe
Novel Quantitative Macro Biomolecule Analysis Based On A Micro Coulter Counter, Y Han, H. Wu, F. Liu, Gang Cheng, Jiang Zhe
Dr. Jiang Zhe
We demonstrate quantitative biomolecule analysis using a micro coulter counter. Specific binding between antibody functionalized microparticles and target biomolecule cause large aggregates of microparticles. The micro coulter counter was employed to measure aggregation ratio, ratio of the aggregate counts to the total particle counts. Goat anti-rabbit IgG, used as a model biomarker, were tested in this paper. The experiment results showed that the aggregation ratio increases with the increasing biomolecule concentration, and the detectable concentration range from 16 to 160 ng/ml was achieved.
Static And Dynamic Responsive Behavior Of Polyelectrolyte Brushes Under External Electrical Field, Hui Ouyang, Zhenhai Xia, Jiang Zhe
Static And Dynamic Responsive Behavior Of Polyelectrolyte Brushes Under External Electrical Field, Hui Ouyang, Zhenhai Xia, Jiang Zhe
Dr. Jiang Zhe
The static and dynamic behaviors of partially charged and end-grafted polyelectrolyte brushes in response to electric fields were investigated by means of molecular dynamics simulation. The results show that the polymer brushes can be partially or fully stretched by applying an external electric field. Moreover, the brushes can switch reversibly from collapsed to stretched states, fully responding to the AC electric stimuli, and the gating response frequency can reach a few hundred MHz. The effects of the grafting density, the charge fraction of the brushes and the strength of the electric field on the average height of the polymer brushes …
High School Bridge Program: A Multidisciplinary Stem Research Program, Jiang Zhe, Dennis Doverspike, Julie Zhao, Paul C. Lam, Craig C. Menzemer
High School Bridge Program: A Multidisciplinary Stem Research Program, Jiang Zhe, Dennis Doverspike, Julie Zhao, Paul C. Lam, Craig C. Menzemer
Dr. Jiang Zhe
A Science, Technology, Engineering and Math (STEM) summer Bridge Program was developed for high school students. The program was designed to encourage students to consider choosing an engineering major in college and to explore STEM as a future career. This was accomplished through a 10-week program involving multidisciplinary research activities. The participants in the program included 33 high school students. Among former participants in position to make a choice in terms of attending college, 100% had chosen to continue on in college, and 86% had chosen to major in a STEM area. The results indicated that that the program had …
An Evaluation Of A Stem Program For Middle School Students On Learning Disability Related Ieps, Paul C. Lam, Dennis Doverspike, Julie Zhao, Jiang Zhe, Craig C. Menzemer
An Evaluation Of A Stem Program For Middle School Students On Learning Disability Related Ieps, Paul C. Lam, Dennis Doverspike, Julie Zhao, Jiang Zhe, Craig C. Menzemer
Dr. Jiang Zhe
A year long Science, Technology, Engineering and Math (STEM) program was developed for middle schools students on Individualized Education Programs (IEPs) involving learning disabilities. The workshops were designed to encourage students both on IEPs and not on IEPs to explore STEM as a future career choice by building their knowledge and confidence. The participants in the workshops included 11 students on IEPs and 15 students not on IEPs. Parents also provided feedback regarding their attitudes toward the program. The results indicated that there were increases in student participant knowledge and career interest for both the students not on IEPs and …
Passive Continuous Particle Focusing In A Microchannel With Symmetric Sharp Corner Structures, Liang-Liang Fan, Liang Zhao, Xu-Kun He, Hand Yu, Qing-Yu Wei, Jiang Zhe
Passive Continuous Particle Focusing In A Microchannel With Symmetric Sharp Corner Structures, Liang-Liang Fan, Liang Zhao, Xu-Kun He, Hand Yu, Qing-Yu Wei, Jiang Zhe
Dr. Jiang Zhe
We report a continuous passive particle focusing method using a novel microchannel with symmetric sharp corners which induce curved streamlines and large centrifugal force on particles. At appropriate flow rate, the centrifugal force generated on particles exceeds the inertial lift force; particles driven by the centrifugal force migrate toward the center of the microchannel, achieving continuous particle focus-ing. With simple structure and operation, this method can be potentially used in particle focusing and ex-traction processes in a variety of lab-on-a chip applications.
A New Look At Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung
A New Look At Optimum Design For Convecting-Radiating Annular Fins Of Trapezoidal Profile, Benjamin T.F. Chung
Dr. Benjamin T.F. Chung
This paper deals with a controversial problem in answering the question “Does the optimum fin design always exist? If not, what are the optimization ranges and limitations?” These authors employ a general example of convecting-radiating trapezoidal annular fin with heat transfer at the tip and wall resistance at the interface. The present results indicate that the answer to the above first question is negative. The ranges of fin optimum design under different thermal and physical conditions are proposed. The effects of Biot number, radiation number, the heat loss at the tip, fin profile and overall wall resistance on fin optimization …
A Cell Model For Ductile Fracture With Applications, C. Fong Shih, Li Cheng, J. Faleskog, Xiaosheng Gao
A Cell Model For Ductile Fracture With Applications, C. Fong Shih, Li Cheng, J. Faleskog, Xiaosheng Gao
Dr. Xiaosheng Gao
No abstract provided.
Analysis Of Ductile To Cleavage Transition In Part-Through Cracks Using The Cell Model Incorporating Statistics, Xiaosheng Gao, J. Faleskog, C. Fong Shih
Analysis Of Ductile To Cleavage Transition In Part-Through Cracks Using The Cell Model Incorporating Statistics, Xiaosheng Gao, J. Faleskog, C. Fong Shih
Dr. Xiaosheng Gao
This paper describes an approach to study ductile/cleavage transition in ferritic steels using the methodology of a cell model for ductile tearing incorporating weakest link statistics. The model takes into account the constraint effects and puts no restriction on the extent of plastic deformation or amount of ductile tearing preceding cleavage failure. The parameters associated with the statistical model are calibrated using experimental cleavage fracture toughness data, and the effect of threshold stress on predicted cleavage fracture probability is investigated. The issue of two approaches to compute Weibull stress, the ‘history approach’ and the ‘current approach’, is also addressed. The …
A Mechanism-Based Approach For Predicting Ductile Fracture Of Metallic Alloys, Xiaosheng Gao
A Mechanism-Based Approach For Predicting Ductile Fracture Of Metallic Alloys, Xiaosheng Gao
Dr. Xiaosheng Gao
Ductile fracture in metallic alloys often follows a multi-step failure process involving void nucleation, growth and coalescence. Because of the difference in orders of magnitude between the size of the finite element needed to resolve the microscopic details and the size of the engineering structures, homogenized material models, which exhibits strain softening, are often used to simulate the crack propagation process. Various forms of porous plasticity models have been developed for this purpose. Calibration of these models requires the predicted macroscopic stress-strain response and void growth behavior of the representative material volume to match the results obtained from detailed finite …
Enabling And Understanding Failure Of Engineering Structures Using The Technique Of Cohesive Elements, H. Jiang, Xiaosheng Gao, T. S. Srivatsan
Enabling And Understanding Failure Of Engineering Structures Using The Technique Of Cohesive Elements, H. Jiang, Xiaosheng Gao, T. S. Srivatsan
Dr. Xiaosheng Gao
In this paper, we describe a cohesive zone model for the prediction of failure of engineering solids and/or structures. A damage evolution law is incorporated into a three-dimensional, exponential cohesive law to account for material degradation under the influence of cyclic loading. This cohesive zone model is implemented in the finite element software ABAQUS through a user defined subroutine. The irreversibility of the cohesive zone model is first verified and subsequently applied for studying cyclic crack growth in specimens experiencing different modes of fracture and/or failure. The crack growth behavior to include both crack initiation and crack propagation becomes a …
Numerical Modeling Of The Constraint Effects On Cleavage Fracture Toughness, Sunil Prakash, Xiaosheng Gao, T. S. Srivatsan
Numerical Modeling Of The Constraint Effects On Cleavage Fracture Toughness, Sunil Prakash, Xiaosheng Gao, T. S. Srivatsan
Dr. Xiaosheng Gao
Cleavage fracture has been an important subject for engineers primarily because of its catastrophic nature and consequences. Experimental studies of cleavage fracture did reveal a considerable amount of scatter and provided evidence of noticeable constraint effects. This did provide the motivation for the development of statistical-based and micromechanics-based methods in order to both study and analyze the problem. The Weibull stress model, which is based on the weakest link statistics, uses two parameters (m and σ u) to effectively describe the inherent distribution of the micro-scale cracks once plastic deformation has occurred and to concurrently define the relationship between the …
Analysis Of Loading Rate Effects On Cleavage Fracture Toughness Of Ferritic Steels, Xiaosheng Gao, Robert H. Dodds Jr.
Analysis Of Loading Rate Effects On Cleavage Fracture Toughness Of Ferritic Steels, Xiaosheng Gao, Robert H. Dodds Jr.
Dr. Xiaosheng Gao
No abstract provided.
A Versatile Microparticle-Based Immunoaggregation Assay For Macromolecular Biomarker Detection And Quantification, Haiyan Wu, Yu Han, George G. Chase, Qiong Tang, Chen-Jung Lee, Bin Cao, Jiang Zhe, Gang Cheng
A Versatile Microparticle-Based Immunoaggregation Assay For Macromolecular Biomarker Detection And Quantification, Haiyan Wu, Yu Han, George G. Chase, Qiong Tang, Chen-Jung Lee, Bin Cao, Jiang Zhe, Gang Cheng
Dr. Jiang Zhe
The rapid, sensitive and low-cost detection of macromolecular biomarkers is critical in clinical diagnostics, environmental monitoring, research, etc. Conventional assay methods usually require bulky, expensive and designated instruments and relative long assay time. For hospitals and laboratories that lack immediate access to analytical instruments, fast and low-cost assay methods for the detection of macromolecular biomarkers are urgently needed. In this work, we developed a versatile microparticle (MP)-based immunoaggregation method for the detection and quantification of macromolecular biomarkers. Antibodies (Abs) were firstly conjugated to MP through streptavidin-biotin interaction; the addition of macromolecular biomarkers caused the aggregation of Ab-MPs, which were subsequently …
Effect Of Lcp Addition On The Properties Of Hybrid Composites, Sreekumar Pisharath, Shing Chung Josh Wong
Effect Of Lcp Addition On The Properties Of Hybrid Composites, Sreekumar Pisharath, Shing Chung Josh Wong
Dr. Shing-Chung Josh Wong
A hybrid composite consisting of rubber toughened nylon 6,6, glass fiber and LCP was investigated by varying LCP content. The hybrid system exhibited better processability than the glass fiber reinforced composite. A decrease in the total torque was observed with the LCP content indicating the reduction in the energy consumed during the processing of the hybrid composites. Thermal stability of the glass fiber reinforced composites improved with LCP addition. SEM observation of the tensile fracture surface revealed LCP fibrillation in the toughened matrix.
Measurement Of Adhesion Energy Of Electrospun Polymer Membranes Using A Shaft-Loaded Blister Test, Shing Chung Josh Wong, Haining Na, Pei Chen
Measurement Of Adhesion Energy Of Electrospun Polymer Membranes Using A Shaft-Loaded Blister Test, Shing Chung Josh Wong, Haining Na, Pei Chen
Dr. Shing-Chung Josh Wong
This study aims to examine the adhesion work of electrospun polymer nano- and micro-fibers. The adhesion energy at the interface of electrospun membrane and a rigid substrate is characterized by a shaft-loaded blister test (SLBT). By controlling the processing parameters, polyvinylidene fluoride (PVDF) fibrous membranes are prepared with fiber diameters ranging from 201 ± 86 nm to 2,724 ± 587 nm. The adhesion energy between electrospun membrane and rigid substrate increases from 8.1 ± 0.7 mJ/m2 to 258.8 ± 43.5 mJ/m2 by use of smaller fiber diameters. Adhesion energies between electrospun PVDF membranes and SiC substrates made of different grain …
Electrospun Polymeric Membranes For Adhesion, Johnny F. Najem, Shing Chung Josh Wong, Guang Ji
Electrospun Polymeric Membranes For Adhesion, Johnny F. Najem, Shing Chung Josh Wong, Guang Ji
Dr. Shing-Chung Josh Wong
With growing interest in detachable adhesives, new materials are explored such as the types that employ elastomers, thermoplastics, and pressuresensitive polymers [1]. Generally, these adhesives produce substantial shear adhesion strengths but are considerably difficult to detach from surfaces. Commercial high strength adhesives make use of chemical interactions such as glues and permanently attach two surfaces. Subsequently, fabrication of dry adhesives with anisotropic force distributions has the potential in several applications such as tapes, fasteners, treads of wall-climbing robots, spiderman's suits, microelectronics, medical and space applications. High aspect ratio (AR) structures exhibit significant shear adhesion strength compared to ones with low …
Polymer Fiber Arrays For Adhesion, Shing Chung Josh Wong, Johnny F. Najem, Guang Ji, Shuwen Chen
Polymer Fiber Arrays For Adhesion, Shing Chung Josh Wong, Johnny F. Najem, Guang Ji, Shuwen Chen
Dr. Shing-Chung Josh Wong
The ability of geckos to adhere to vertical solid surfaces comes from their remarkable feet with millions of projections terminating in nanometer spatulae. In this paper, we present a simple yet robust method for fabricating directionally sensitive dry adhesives. By using electrospun nylon 6 nanofiber arrays, we create gecko-inspired dry adhesives, that are electrically insulating, and that show shear adhesion strength of 27 N/cm2 on a glass slide. This measured value is 270% that reported of gecko feet and 97-fold above normal adhesion strength of the same arrays. The data indicate a strong shear binding-on and easy normal lifting-off. Size …
Analysis Of Short Crack Growth In Particulate Composites, Ying Zhang, Tsuchin P. Chu, Ajay Mohan Mahajan, Chi Tsieh Liu
Analysis Of Short Crack Growth In Particulate Composites, Ying Zhang, Tsuchin P. Chu, Ajay Mohan Mahajan, Chi Tsieh Liu
Dr. Ajay Mahajan
This paper presents the analysis of the short-crack propagation and growth in particulate composite materials by using the image correlation techniques and fracture mechanics theory. The fracture mechanics model for a long crack does not work very well with short-crack propagation when the initial crack length is less than 5.1 mm (0.2 inch). In order to investigate the short crack effect, a series of tests of particulate composite specimens with long and short cracks have been performed and the results were recorded on a video tape. These test data were analyzed to determine the strain fields near the crack tip, …
Local Material Properties Meausrement Using Ultrasonic C-Scan Techniques, Dooheon Kim, Tsuchin P. Chu, Ajay Mohan Mahajan
Local Material Properties Meausrement Using Ultrasonic C-Scan Techniques, Dooheon Kim, Tsuchin P. Chu, Ajay Mohan Mahajan
Dr. Ajay Mahajan
Mechanical material properties of concrete specimen are evaluated locally and non-destructively using an ultrasonic C-scan system. The time of flight of the sound wave between front surface and back surface for test samples was measured. Local Young's modulus at scanning point and average Young's modulus of entire specimen are calculated. Testing techniques are developed by calibrating the transducer not only to compensate for the time delay but also to control the measurement of properties of interest, such as true density and local thickness. In order to obtain additional mechanical property, such as Poisson's ratio, the transverse velocities of the wave …
Real-Time Measurement Of Surface Deformation Of Rotating Blades, Jay Maudlin, Ajay Mohan Mahajan, Tsuchin P. Chu
Real-Time Measurement Of Surface Deformation Of Rotating Blades, Jay Maudlin, Ajay Mohan Mahajan, Tsuchin P. Chu
Dr. Ajay Mahajan
This paper presents the results for the real-time measurement of surface deformation of rotating elements. A digital image correlation technique is used to estimate the surface displacements and strains. Speckle patterns are spray painted on the surface of interest and digital images taken before and during deformation caused by rotary motion. The digital image of the deformed blade is taken by freezing the speckled pattern with the help of a stroboscope. The technique provides several advantages over traditional methods in terms of obtaining whole-field deformation profiles, a non-invasive measurement scheme, and a simple and economical set-up. Results are presented for …
Particle Swarm Optimization Approach For Maximizing The Yield Of A Coal Preparation Plant, Vishal Gupta, Hussain Unjawala, Ajay Mohan Mahajan, Manoj Mohanty
Particle Swarm Optimization Approach For Maximizing The Yield Of A Coal Preparation Plant, Vishal Gupta, Hussain Unjawala, Ajay Mohan Mahajan, Manoj Mohanty
Dr. Ajay Mahajan
This paper presents the use of particle swarm optimization to maximize the clean coal yield of a coal preparation plant that typically has multiple cleaning circuits that produce the same product quality so that the blend of clean coal meets the targeted product quality contraints. Particle swarm is used for the yield optimization while satisfying multiple product quality restraints. The results show a 2.73% increase in the yield can be achieved leading to additional revenue of $5,460,000 per annum for a plant producing 10 million tons of clean coal per year without significantly adding to the implementation/operation cost.
Design, Fabrication, And Properties Of 2-2 Connectivity Cement/Polymer Based Piezoelectric Composites With Varied Piezoelectric Phase Distribution, Xu Dongyu, Cheng Xin, Sourav Banerjee, Huang Shifeng
Design, Fabrication, And Properties Of 2-2 Connectivity Cement/Polymer Based Piezoelectric Composites With Varied Piezoelectric Phase Distribution, Xu Dongyu, Cheng Xin, Sourav Banerjee, Huang Shifeng
Sourav Banerjee
The laminated 2-2 connectivity cement/polymer based piezoelectric composites with variedpiezoelectric phase distribution were fabricated by employing Lead Zirconium Titanate ceramicas active phase, and mixture of cement powder, epoxy resin, and hardener as matrix phase with a mass proportion of 4:4:1. The dielectric, piezoelectric, and electromechanical coupling properties of the composites were studied. The composites with large total volume fraction ofpiezoelectric phase have large piezoelectric strain constant and relative permittivity, and thepiezoelectric and dielectric properties of the composites are independent of the dimensional variations of the piezoelectric ceramic layer. The composites with small total volume fraction of piezoelectric phase have large …
Elastic Wave Field Computation In Multilayered Nonplanar Solid Structures: A Mesh-Free Semianalytical Approach, Sourav Banerjee, Tribikram Kundu
Elastic Wave Field Computation In Multilayered Nonplanar Solid Structures: A Mesh-Free Semianalytical Approach, Sourav Banerjee, Tribikram Kundu
Sourav Banerjee
Multilayered solid structures made of isotropic, transversely isotropic, or general anisotropic materials are frequently used in aerospace, mechanical, and civil structures. Ultrasonic fields developed in such structures by finite size transducers simulating actual experiments in laboratories or in the field have not been rigorously studied. Several attempts to compute the ultrasonic field inside solid media have been made based on approximate paraxial methods like the classical ray tracing and multi-Gaussian beam models. These approximate methods have several limitations. A new semianalytical method is adopted in this article to model elastic wave field in multilayered solid structures with planar or nonplanar …
Phonon Confinement Using Spirally Designed Elastic Resonators In Discrete Continuum, Sourav Banerjee, Raiz U. Ahmed
Phonon Confinement Using Spirally Designed Elastic Resonators In Discrete Continuum, Sourav Banerjee, Raiz U. Ahmed
Sourav Banerjee
Periodic and chiral orientation of microstructures, here we call phononic crystals, have extraordinary capabilities to facilitate the innovative design of new generation metamaterials. Periodic arrangements of phononic crystals are capable of opening portals of non-passing, non-dispersive mechanical waves. Defying conventional design of regular periodicity, in this paper spirally periodic but chiral orientation of resonators are envisioned. Dynamics of the spirally connected resonators and the acoustic wave propagation through the spirally connected multiple local resonators are studied using fundamental physics. In present study the spiral systems with local resonators are assumed to be discrete media immersed in fluid. In this paper …
The Integrated Systems Engineering Laboratory- An Innovative Approach To Vertical Integration Using Modern Instrumentation, Ajay Mahajan, Maurice Walworth, David Mcdonald, Kevin Scmaltz
The Integrated Systems Engineering Laboratory- An Innovative Approach To Vertical Integration Using Modern Instrumentation, Ajay Mahajan, Maurice Walworth, David Mcdonald, Kevin Scmaltz
Dr. Ajay Mahajan
The current paradigm in engineering course instruction builds on a lecture prerequisite structure but ignores the need for a laboratory prerequisite structure. Educational quality is therefore diminished as instructors optimize specific laboratories but fail to optimize the overall program laboratory experience. This paper presents a learning environment based on modern instrumentation that forces students to use not only concepts and skills acquired from the lecture, but also actual data and models acquired from lower division laboratories, in upper division laboratories. The vertical integration occurs because students must utilize their previous laboratory work as a reference and/or building blocks as they …
Diabetic Patients Foot Care Using Smart Materials To Prevent Ulcerations/Amputations, Carrie Hahn, Ajay Mahajan, Marco P. Schoen
Diabetic Patients Foot Care Using Smart Materials To Prevent Ulcerations/Amputations, Carrie Hahn, Ajay Mahajan, Marco P. Schoen
Dr. Ajay Mahajan
A major cause of illness and disability in diabetic patients is complications affecting the lower limbs, particularly the feet where loss of feeling may result in ulcerations, and ultimately to partial or total amputation. Traditional remedies for this problem still remains in measuring the foot pressures and then designing a passive shoe insert that absorbs the high pressures. This process may then be repeated multiple times during the lifetime of the patient. This paper describes the conceptual design of an automatic system that monitors and controls the pressure levels in diabetic patients’ feet in real time. The scheme is based …
High Ppeed Circuit Techniques For Network Intrusion Detection Systems (Nids), Ajay Mohan Mahajan
High Ppeed Circuit Techniques For Network Intrusion Detection Systems (Nids), Ajay Mohan Mahajan
Dr. Ajay Mahajan
No abstract provided.