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Rensselaer Polytechnic Institute
Graduate Research Symposium
March 23th-24th 2018
ABSTRACTS
2
Contents Garo Agopian ................................................................................................................................................ 4
Anna Thonis .................................................................................................................................................. 5
Hayley McCullough ...................................................................................................................................... 6
Kathleen Morrissey ....................................................................................................................................... 7
Clifford Morrison .......................................................................................................................................... 8
Nathaniel Anderson ...................................................................................................................................... 9
Colin Garvey ............................................................................................................................................... 10
Indrani Bhattacharya ................................................................................................................................... 11
Abhishek Choudhary .................................................................................................................................. 12
Courtney Walton ......................................................................................................................................... 13
Ellie Irons .................................................................................................................................................... 14
Jennifer Howell-Clark ................................................................................................................................. 15
Tyree Ratcliff .............................................................................................................................................. 16
Montwaun Young ....................................................................................................................................... 17
Akashdeep Singh Virk ................................................................................................................................ 18
Mohammad Islam ....................................................................................................................................... 19
Siddharth Sundararaman ............................................................................................................................. 20
Majeed Simaan............................................................................................................................................ 21
Rufeng Ma .................................................................................................................................................. 22
Fangheng Sun.............................................................................................................................................. 23
Charles Hathaway ....................................................................................................................................... 24
Alagu Chidambaram ................................................................................................................................... 25
Brian Molnar ............................................................................................................................................... 26
Garett MacLean .......................................................................................................................................... 27
Matthew Dellehunt ...................................................................................................................................... 28
Jonathan Kulwatno ...................................................................................................................................... 29
Stephanie Jennings ...................................................................................................................................... 30
Xiangyu Gong ............................................................................................................................................. 31
Ashok Williams .......................................................................................................................................... 32
Jane Thibeault ............................................................................................................................................. 33
Amelia Peterson .......................................................................................................................................... 34
Robert Altman ............................................................................................................................................. 35
3
James Hu ..................................................................................................................................................... 36
Carlos Ivan Rivera-Gonzalez ...................................................................................................................... 37
Diana Ramirez-Rios .................................................................................................................................... 38
Jennifer Rico-Varela ................................................................................................................................... 39
Rachel Dass ................................................................................................................................................. 40
Dhruv Patel ................................................................................................................................................. 41
Manish Bhat ................................................................................................................................................ 42
Anirban Chandra ......................................................................................................................................... 43
Zhongqian Lin ............................................................................................................................................. 44
Syed Islam ................................................................................................................................................... 45
Michael Jenkinson ...................................................................................................................................... 46
Antwane Mason .......................................................................................................................................... 47
4
Garo Agopian1, Gina O'Connor1
1Rensselaer Polytechnic Institute
Establishing a Breakthrough Innovation Capability: The Case of SE Denmark
This case study explores a complex social phenomenon: establishing a breakthrough innovation
(BI) capability in a large, mature company under threat. The initiation and emergence of the capability are
the focus of the study. SE Denmark, a Danish energy and utilities company, is the subject case. Data
include depth interviews with company executives. Process mapping was used to analyze the data. The
research questions are based on Van de Ven and Huber’s (1990) framework for organizational change.
The analysis suggest that a newly established BI capability cannot start out working in a vacuum,
especially when the company has not had innovation as part of its ongoing business environment; it must
partner with existing business units and start out with aligned opportunities. While BI is the objective,
sometimes companies are so atrophied in their ability to innovate that this function starts with incremental
ideas; with time, the innovation group learns and becomes more trusted throughout the organization, and
the degree of innovativeness increases. The external threat creates enough urgency for company
executives to continue to improve this capability rather than backing away, as many companies do.
5
Anna Thonis1, Bradford Lister1
1Rensselaer Polytechnic Institute
Predicting Climate-Induced Distributional Shifts for Puerto Rican Anoles
With some 400 known species, the lizard genus Anolis is the most speciose group of terrestrial
vertebrates in the world. Widely distributed, they occur throughout Central and South America, the West
Indies, and the southeastern United States. Although anoles have emerged as paradigmatic species in
ecology and evolution, relatively little research has addressed the effects of climate change on their
distributions. Over the past 40 years, Puerto Rico has experienced steady increases in ambient
temperature with mean maximum temperatures rising by as much as 2°C. Using distribution data from the
Puerto Rico Gap Analysis, WorldClim bioclimatic variables, and MaxEnt niche modeling software, we
projected potential changes in the distribution of ten species of Puerto Rican anoles for 2050 and 2070.
Our models used the HadGEM2-AO Global Climate Model paired with the IPCC’s Representative
Concentration Pathways (RCPs). RCP8.5 was chosen as it represents a likely scenario of continued high
greenhouse gas emissions through 2100. Under HadGEM2-AO RCP8.5 for 2050, Anolis krugi, A.
evermanni, and A. gundlachi are the most negatively impacted species, while for 2070 the most
negatively impacted species are A. gundlachi, A. evermanni, and A. cristatellus. The model also predicts
reductions in most suitable habitat across all ten Anolis species, ranging from -29.4% by 2050 to -39.6%
by 2070. Our study provides insights into the potential impact of continued climate change on Puerto
Rican anoles, and most likely other West Indian Anolis species, and has important implications for future
conservation efforts.
6
Hayley McCullough1
1Rensselaer Polytechnic Institute
A Linguistic Analysis of the Rhetoric of Academic Articles in Psychology
The present study explores rhetoric in a quantitative manner by using integrative complexity and
its subtypes – linguistic variables that measure differentiation and integration – as dependent variables to
test possible correlations between the complexity of a published, peer-reviewed psychology article and
the number of times it is subsequently cited after publication. Eighty articles were randomly selected and
scored for complexity using the Automated Integrative Complexity (Conway et al., 2014; Houck et al.,
2014). Individual one-way ANOVAs revealed statistically significant main effects for all three types of
complexity, revealing predominantly curvilinear mean patterns: the lowest complexity scores appearing at
the two extreme of the spectrum and the highest complexity scores appearing in the middle. These
findings provide unique insight into the underlining psychology of the academic publication process and
into how rhetoric manifests across the quality spectrum, suggesting a general preference towards
simplicity in writing amongst academics; however, these findings also show that factors beyond
integrative complexity also influence an article’s subsequent citation count. Overall, the consistency and
overall strength of the present study’s results, despite the novelty and exploratory nature, provide a solid
foundation and justification for future quantitative rhetoric explorations in this research vein.
7
Kathleen Morrissey1
1Rensselaer Polytechnic Institute
Potential G-quadruplex Forming Aptamers using a Genome-Inspired Reverse Selection Approach
Aptamers have become one of the leading alternatives to antibodies as affinity reagents to a wide
variety of targets including proteins. They were first discovered in 1990 using the process known as
Systematic Evolution of Ligands by Exponential Enrichment (SELEX). In this process, oligonucleotides
are selected from a combinatorial library for high affinity, highly selective binding to a specific target.
SELEX has discovered many aptamers but it does come with limitations that can hinder the process of
aptamer discovery, particularly in the case of potential aptamers that form multi-tier G-quadruplexes
(G4). G-quadruplex-forming sequences are found throughout the human genome and merit investigation
as potential aptamers. In our lab, we have developed a new genome-inspired, reverse selection approach
that allows us to explore these and other challenging secondary structures. In the reverse selection
approach, a specific DNA sequence from the human genome is used for affinity capture of proteins from
natural pools such as nuclear extracts. The nuclear extracts are incubated with streptavidin magnetic
beads coated with biotin-modified G4 oligonucleotides or control oligonucleotides. A rapid screening for
captured proteins is performed using MALDI-TOF MS to determine if there is any affinity capture of
proteins specific for the G4 DNA. If affinity capture is established, the capture experiments are repeated
on a larger scale and captured proteins are separated by gel electrophoresis. Bands specific for G4 DNA
are analyzed by LC-MS/MS to produce a list of possible protein matches. This list is used to guide our
selection of proteins for further interrogation using Western blots. Here we will present our results for
genomic-G4 forming sequences from the promoter regions of the human oncogenes c-myc, Rb, and
VEGF as potential aptamers toward proteins in nuclear extracts from the basal breast cancer cell line
MDA-MB-468.
8
Clifford Morrison1
1Rensselaer Polytechnic Institute
Electrochemical Bioreactor Technology for Chemical and Biological Applications
Two seemingly distinct fields, industrial biocatalysis and microbial electrosynthesis, will be
viewed together through the lens of electrochemical bioreactor technology in order to highlight the
challenges that exist in creating a versatile platform technology for use in chemical and biological
applications. Industrial biocatalysis applications requiring NAD(P)H to perform redox transformations
often necessitates convoluted coupled-enzyme regeneration systems to regenerate reduced cofactor,
NAD(P)H from oxidized cofactor, NAD(P). Renewed interest in continuously recycling the cofactor via
electrochemical reduction is motivated by the low cost of performing electrochemical reactions, easy
monitoring of the reaction progress, and straightforward product recovery. However, electrochemical
cofactor regeneration methods invariably produce adventitious reduced cofactor side products which
result in unproductive loss of input NAD(P). Strategies for mitigating the loss of cofactor material in
industrially-scalable systems will be discussed. Microbial electrosynthesis is a form of microbially-driven
catalysis in which electricity is supplied to living microorganisms for the production of industrially-
relevant chemical products at higher carbon efficiencies and yields as compared to traditional, non-
electrically driven, fermentations. The biological engineering challenges involved in this task, and the
ways in which these challenges inform better electrochemical bioreactor design, will be discussed.
9
Nathaniel Anderson1, Peter Dinolfo2, Xing Wang2
1Rensselaer Polytechnic Institute
2Center for Biotechnology and Interdisciplinary Studies
Center for Biotechnology and Interdisciplinary Studies
The ability to position light absorbing molecules with precision in the nanoscale has a large effect
on the efficiency of the transfer of energy between chromophores. Solar energy producing technologies
rely heavily on this performance and how well that energy can be passed into the system. Utilizing the
self-assembly of DNA nanostructures gives the ability to position and orient such chromophores with
nanometer resolution. In this work, DNA nanostructures combined with the versatile CuAAC click
chemistry reactivity is used to form a new scaffold onto which energy donor molecules can be positioned
around a central attachment point. The scaffold is built using a porphyrin molecule as the attachment
point allowing for convenient morphology for multiple single-stranded oligonucleotides to be covalently
bound. The porphyrin also acts as an energy transfer acceptor through Förster Resonance Energy
Transfer. This new scaffold has been purified, characterized, and used as an energy transfer system with
transfer efficiency nearing 90%. It provides a model system to identify parameters important to designing
robust energy transfer systems without the need for more complicated and potentially low yielding
chemistry necessary for nanoscale positioning.
10
Colin Garvey1
1 Rensselaer Polytechnic Institute
On the Democratization of Artificial Intelligence
Recently the "democratization" of artificial intelligence (AI) has been taken by several major tech
companies. What does this explicitly political claim mean? Some companies are offering APIs, libraries,
and developer tools online for free. There are two problems with calling this "democracy." First, how
does it differ from earlier "open source" efforts? Even where resources are made available, scarcities in
access make widespread participation practically unrealizable; a "digital divide" separates haves from
have-nots. Second, it is unclear that open access to datasets and AI tools online will contribute in any
meaningful way to improved democratic governance of society, or AI R&D itself. A stronger sense of
political democracy is needed. What would it mean to take seriously the political dimensions of the
"democratization" of AI? Applying Woodhouse's 20-point framework for demo-cratic decision making
through intelligent trial and error (ITE), our evaluation of AI R&D found considerable barriers to
democratization. 1) public deliberation is impaired by deterministic framings of AI's developmental
trajectory, prohibiting partisan disagreement and restricting discussion to a narrow set of concerns; (2)
most decision making processes are opaque, exclude most stakeholders, and allocate authority to
technical experts and business executives; (3) the rapid pace of AI R&D mitigates against stringent initial
precautions and disallows time for social organizations to learn and respond. Because addressing these
issues requires changes to the AI R&D process, the democratization of AI therefore requires social
innovations.
11
Indrani Bhattacharya1, Richard Radke1
1Rensselaer Polytechnic Institute
Cognitive Environments that Facilitate Group Decision Making
Humans invest substantial time, energy, and money in group meetings in professional
environments every day. However, meetings are often inefficient, unfocused, and poorly documented.
Our vision is to create a multi-modal sensor-enabled room with advanced cognitive computing
capabilities. These include actively tracking the location, pose, and visual focus of attention of the
participants; distinguishing and clearly isolating the speech of several people talking at the same time;
learning and remembering the context of previous meetings; generating automated summaries; analyzing
participation shifts and meeting productivity; and ultimately contributing in real time to facilitate group
decision making. In addition to its potential economic impact, research in this domain will also assist
social psychologists interested in studying human interaction patterns in group meetings. Since meeting
participants could feel uncomfortable, self-conscious, or inhibited in the presence of active video cameras,
we instead propose privacy-preserving methods for human tracking using a sparse array of ceiling
mounted time-of-flight sensors. By integrating these with non-verbal audio information (speaker
segmentation, interruptions, tone of voice, prosody), we can study participation shifts, interaction links
between participants, and emergent leadership in groups. We evaluate our system on a lunar survival task
dataset collected in the Smart Conference Room at RPI.
12
Abhishek Choudhary1
Peter Kramer1
1Rensselaer Polytechnic Institute
Mathematical Modeling of Intracellular Transport
We present a mathematical framework to analyze the intracellular transport inside an axon. Our
model captures the spatial dynamics and interactions of motor and cargo through a system of coupled
stochastic differential equations. Using the techniques of asymptotic analysis, the first passage time for
the reattachment of a tethered motor is computed. Through the application of renewal-reward theory we
are able to derive the key quantities of interest for the transport processes spanning over multiple attached
and detached phases of a single molecular motor and cargo complex.
13
Courtney Walton1, Judy Wu1, Jacob Shelley1
1Rensselaer Polytechnic Institute
Detection and Sequencing of Biomolecules using Solution-Cathode Glow Discharge Mass Spectrometry
Many fields, especially those considered –omics, i.e. metabolomics, proteomics are in need of
fast, sensitive methods that can provide molecular information. Mass spectrometry is an analytical
technique that provides such information for biomolecules, but continues to rely on complex and costly
instruments capable of controllably fragmenting biopolymers for structural elucidation. Therefore, it
would be advantageous to develop an ionization source that, when paired with any mass spectrometer,
could tunably produce intact molecular ions and information-rich fragments.
We have recently found an ionization source capable of this feat: the solution-cathode glow
discharge (SCGD), which is an atmospheric-pressure glow discharge. The plasma of the SCGD is
sustained between a metal anode and a flowing, conductive solution, which serves as the cathode.
Analytes within the liquid stream are sputtered from solution and ionized by the glow discharge. The
SCGD is unique in that it produces both intact, gas-phase ions from labile biomolecules and with
parameter changes yields fragmentation of the species within the source. This presentation will focus on
the SCGD as an ionization source for biomolecule mass spectrometry. Recent progress in the detection
and tunable fragmentation of biomolecules including the ability to couple this source with high-
performance liquid chromatography (HPLC) will be demonstrated.
14
Ellie Irons1
1Rensselaer Polytechnic Institute
Social-Ecological Art and Public Fieldwork in the (so-called) Anthropocene
This talk explores socially-engaged, environmentally oriented art in the context of the
Anthropocene debate, through the lens of my engagement with weedy plants and urban ecology. Focusing
on my collaborative project the Environmental Performance Agency (EPA*), I trace an interdisciplinary
path from feminist land art of the 1960s through social practice art and tactical biopolitics in the 2000s,
setting the stage for my current commitment to an artistic methodology I call “public fieldwork”. Drawing
on EPA* activities, I investigate the benefits of open, publicly accessible exchange between art and
ecology, and between humans and other life forms. Responding to Born and Berry’s concept of the
“public experiment” I explore tactics for resisting damaging dualisms arising from the simplification of
fields like Invasion Biology and Restoration Ecology. The artist/fieldworker becomes an intermediary to
dispel plant blindness and encourage place-based awareness of the more-than-human habitats we create in
constructing our cities.
*Named in response to the proposed defunding of the US Environmental Protection Agency, the
Environmental Performance Agency has no affiliation with the US EPA, but has consciously chosen to
appropriate its acronym."
15
Jennifer Howell-Clark1, Christian Wetzel1, T. Paul Chow1, Zhibo Guo1
1Rensselaer Polytechnic Institute
Impurity Control for High Performance Gallium Nitride Devices
Gallium Nitride (GaN) is an attractive choice for high-voltage power devices due to its high
breakdown field (> 3 MV/cm). This property, stemming from its wide band gap of 3.4 eV, allows for
large voltages to be supported on thinner, more heavily doped layers than would be possible for
conventional materials like silicon, which have smaller critical fields. Consequently, the on-resistance of
high voltage power devices can be reduced, improving the design tradeoffs of semiconductor power
devices by an order of magnitude or more; these improvements allow for more efficient power electronic
systems.
However, the material properties of GaN present several practical challenges which are not
encountered in silicon. Many of these challenges center on doping and impurities. Magnesium is the only
impurity that has been shown to reliably result in p-type conductivity in GaN, but Mg performs poorly in
comparison to p-type doping in silicon. We seek to both improve upon existing Mg doping techniques,
and to explore alternate impurities and methods for use in high-voltage power devices. In device
structures where Mg is not necessary, we are investigating the feasibility of using carbon as an acceptor
impurity, enabling device structures and designs that would otherwise not be possible.
16
Tyree Ratcliff1
1Rensselaer Polytechnic Institute
Development of a Transferable Atom Equivalent method for Materials QSPR (Quantitive Structure
Property Relationship) modeling of metal containing systems.
The Quantum Theory of Atoms in Molecules is used to build a library of Transferable Atom
Equivalent (TAE) descriptors capable of adequately describing the quantum-chemical properties of metal-
containing organometallic materials. The development of metal-based TAE descriptors allows for more
precise description of the chemical space with greatly diminished calculation time, providing better
modeling potential. The goal of this project is to facilitate the advancement and development of novel
materials that are capable of meeting the demands of a growing technological age. With the development
of TAE techniques for coordination environments, metal TAE descriptors can be developed and applied
to a range of molecular environments. Once developed, these descriptors will be capable of capturing the
electronic properties of metal systems without a large computational overhead.
17
Montwaun Young1, Sunil Badal1, Jessica Hellinger1, Jacob Shelley1
Rensselaer Polytechnic Institute
Development of a Simultaneous Multimodal Chemical Imaging Platform Based on Optical and Mass
Spectrometries
Recent advances in mass-spectrometry instrumentation have led to several new capabilities,
including the ability to generate chemical images from solid samples. However, unequivocal analyte
identification in these imaging experiments requires multiple analytical approaches performed on the
same sample, termed 'multimodal chemical imaging'. Success in generating high-resolution chemical
images has been achieved with instruments based around mass spectrometry due its high selectivity and
specificity. Several mass-spectral imaging (MSI) techniques have been developed which provide either
molecular or elemental maps as is dictated by the ionization source used. However, mass spectrometry is
inherently a destructive technique (i.e. the analyzed sample is consumed during the analysis). Therefore,
combining MSI with approaches that simultaneously provide orthogonal analytical information would be
most advantageous.
Here, we describe a new multimodal chemical imaging approach to simultaneously provide
molecular and elemental chemical information of solid samples with little to no sample preparation. The
dual imaging approach is achieved through laser sampling followed by simultaneous mass-spectrometric
and optical-emission measurements. Molecular chemical images are obtained by laser ablation followed
by flowing atmospheric-pressure afterglow (FAPA) mass spectrometry. At the same time, optical
emission from a laser-induced plasma is used to provide elemental information. Instrument design and
preliminary figures-of-merit will be presented.
18
Akashdeep Singh Virk1, Zvi Rusak1
1Rensselaer Polytechnic Institute
Transonic flow of steam with non-equilibrium and homogeneous condensation
A small-disturbance model for studying the physical behavior of a steady transonic flow of steam
with non-equilibrium and homogeneous condensation around a thin airfoil is derived. The steam
thermodynamic behavior is described by van der Waals equation of state. The water condensation rate is
calculated according to classical nucleation and droplet growth models. The current study is based on an
asymptotic analysis of the fluid flow and condensation equations and boundary conditions in terms of the
small thickness of the airfoil, small angle of attack, closeness of upstream flow Mach number to unity and
small amount of condensate. The asymptotic analysis gives the similarity parameters that govern the
problem. The flow field may be described by a non-homogeneous transonic small-disturbance equation
coupled with a set of four ordinary differential equations for the calculation of the condensate mass
fraction. An iterative numerical scheme which combines Murman & Cole's (1971) method with
Simpson's integration rule is applied to solve the coupled system of equations. The model is used to study
the effects of energy release from condensation on the aerodynamic performance of airfoils/blades
operating in steam at high pressures and temperatures and near the vapor-liquid saturation conditions.
19
Mohammad Islam1
1Rensselaer Polytechnic Institute
Morphology and mechanics of fungal mycelium
We study here a unique biomaterial developed from fungal mycelium, the vegetative part and the
root structure of fungi. Mycelium has a porous and filamentous network like structure, in which the
mechanics is predominantly determined by individual filament properties and network architecture. We
aim to identify the system parameters that control the mechanical behavior of mycelium based materials
and to develop relevant material design rules. To this end, we report the morphological and mechanical
characterization of mycelium through a synergetic combination of microscopic imaging, mechanical
testing and computational modeling. Our experimental results reveal that mycelium exhibits significant
non-linear stress-strain behavior both under tension and compression. Significantly, we observe that
mycelium exhibits considerable strain hardening before rupture under tension and it mimics open cell
foam behavior under compression with strain dependent hysteresis and stress softening behavior under
cyclic loading condition. Based on our morphological characterization and experimental observations, we
have developed a topologically equivalent random fiber network model which provides further insight
into the microstructural origin of mycelium’s mechanical response.
20
Siddharth Sundararaman1, Liping Huang1, Walter Kob2, Simona Ispas2
1 Rensselaer Polytechnic Institute
2University of Montpellier, Montpellier, France
New Optimization Scheme for Potential Development for Multi-component Oxide Glasses
A dearth of satisfactory interaction potentials for multi-component oxide glasses that can
reasonably describe a variety of properties is a major stumbling block facing the glass community. In this
work, a new optimization scheme was developed to parameterize effective pairwise potentials for
molecular dynamic (MD) simulations of multi-component oxide glasses. Our approach was to fit to
results from accurate first principles calculations and explicitly incorporate the radial distribution function
(RDF) of the equilibrium liquid at multiple temperatures, the vibration density of states (VDOS) and the
density of glass at different pressures into the cost function of the fitting scheme. This new optimization
scheme has successfully improved potentials for silica glass and alkali silicate glasses, which can not only
predict the elastic moduli at ambient conditions, but also their response to external stimuli like high
pressure and temperature. This new optimization schedule is being extended to multi-component oxide
glasses.
21
Majeed Simaan1
1Rensselaer Polytechnic Institute
Estimation Risk and Implicit Value of Index-Tracking
I study Roll’s (1992) conjecture that there may exist an implicit value in index-tracking relative to
forming MV-optimal portfolios. I show, analytically, that the conjectured implicit value is evident in
terms of lower estimation error and higher out-of-sample utility. The implicit value improves with risk
tolerance, asset betas, and the number of assets, however, diminishes with market volatility and sample
size. A battery of empirical tests supports my analytical conclusions and indicate that the implicit value is
most evident in cases associated with high estimation error. The improvement implies higher risk-
adjusted returns, lower volatility, higher Sharpe-ratio, lower turnover, and larger opportunity cost.
22
Rufeng Ma1, Kristen Mills1
1Rensselaer Polytechnic Institute
Mechanosensitivity and motility of NF1+/-, NF2+/- and healthy dermal fibroblasts
Cells sense the physical properties of their extracellular environment and translate them into
biochemical signals. Neurofibromatosis type 1 (NF1) and Neurofibromatosis type 2 (NF2) are two tumor-
associated genetic disorders in which the proteins encoded are involved in the cell mechanosensing or
motility pathways. The neoplastic origin of neurofibromas, benign tumors associated with the disease, are
believed to be NF1-deficient (NF1-/-) Schwann cells, but haploinsufficient (NF1+/-) stromal cells, such as
fibroblasts, are suspected to play a role in the development of tumors associated with the disease. Little
work has been invested to study the mechanobiology of these cells. Here, we present a detailed study of
the influence of local variations in substrate geometry on the spreading, orientation, and stress fiber
expression of dermal fibroblasts (DFs).
23
Fangheng Sun1, Sunil Badal1, Jessica Hellinger1, Jacob Shelley1
1Rensselaer Polytechnic Institute
Mixed-gas Flowing Atmospheric-Pressure Afterglow as an Atmospheric Pressure Chemical- and Photo-
ionization Source for Mass Spectrometry
Plasma-based ambient desorption/ionization (ADI) techniques, which rely on low power
electrical discharges to desorb/ionize analytes from their native environment, have received considerable
attention due to their simple construction and operation, rapid sample analysis times, and high sensitivity.
Most plasma-based ADI sources generally use helium as the discharge gas due to the large reaction cross
section of excited helium species with atmospheric gases, such as N2 and H2O, which leads to substantial
reagent-ion densities and, ultimately, better sensitivity. Despite the extensive use of helium, some mixed-
gas systems have been shown to improve the analytical performance. In the present study, we explore
changes in discharge processes and ionization chemistry, through optical and mass spectrometries, with
the addition of molecular gases to the helium discharge gas of a flowing atmospheric pressure afterglow
(FAPA) ADI source. Furthermore, the role of photons emitted by FAPA glow discharge in analyte
ionization was also studied. The chemical reagent ions and photons were separated by MgF2 window and
only photons were used for analyte ionization. Mass spectra for a range of analytes were collected with
FAPA glow discharge as a photoionization source. Effects of discharge current, discharge gas
composition, and dopants on photoionization characteristics will also be discussed in this presentation.
24
Charles Hathaway1
1Rensselaer Polytechnic Institute
Broadening the Applicability of Software Metrics with Biological BROADENING THE
APPLICABILITY OF SOFTWARE COMPLEXITY METRICS WITH BIOLOGICAL Analogues
Software metrics represent an application of conventional computer science to itself in an attempt
to quantify the complexity of software systems. Many of the conventional metrics proposed in academia
and industry find their roots in a top-down composition that is so similar to the way conventional AI has
been done prior to the surge in machine learning techniques. As software becomes increasingly
networked together, the opportunity for bottom-up approaches to software complexity becomes more
apparent. The complexity concepts created for biological systems, such as ecological biodiversity, neural
pattern recognition, and genetic mutation rate, offer "proof of concept" illustrations that useful global
measures can offer insights into the behavior of complex systems. Thus computational analogs to these
biological complexity metrics may offer deeper understanding of how complexity occurs in contemporary
networked computing systems. We compare traditional software metrics to these bio-inspired measures in
many contexts, such as bug-finding, measuring student comprehension, and using metrics as a way of
quantifying generative justice.
25
Alagu Chidambaram1
1Rensselaer Polytechnic Institute
Electrical Stimulation increases primary human Schwann cell number and supports angiogenesis.
Neurofibromatosis Type 2 (NF2) is an autosomal dominant genetic disorder characterized by
multiple tumors to the nervous system, with the most common being vestibular Schwannoma or acoustic
neuroma. To date, changes to NF-2 Schwannoma cells caused by electrical stimulation have not been
examined. Furthermore, a composite model of the local tumor environment, including vasculature has not
been developed. Human Schwann cells are seeded onto a coverslip and exposed to an electric field. HSC
proliferation was estimated by counting nuclei and comparing to unstimulated control. Early
reorganization of HUVECs was characterized using a 2D angiogenesis kit. Electrical stimulation
increases the growth rate of wild type human Schwann cells and supports angiogenesis. Schwann cell
conditioned medium also supported 2D angiogenesis.
26
Brian Molnar1, Sunil Badal1, Jacob Shelley1
1Rensselaer Polytechnic Institute
Rapid, Plasma-Assisted Synthesis of Unsaturated Carbonyls from n-Alkanes
Unsaturated carbonyl compounds are used extensively as starting materials in industrial and
pharmaceutical syntheses. Well-established synthetic methods such as the aldol condensation offer yields
between 60-80%. However, the requirement for two starting materials and heat can increase production
costs. Furthermore, to improve the reaction yield further requires reaction times in excess of 12 hours and
sometimes additional materials, such as catalysts. Gas-phase synthesis could be an attractive alternative
because it allows for much faster reaction rates by increasing the rate of diffusion and lowering the energy
barrier of the reaction. However, traditional gas-phase synthesis can still proceed slowly. Reaction rates
could be much improved by using gas-phase ion-molecule chemistry. In this work, the afterglow of a
helium atmospheric pressure glow discharge is used to produce gaseous reactant ions, which react rapidly
with neutral aliphatic compounds to yield unique products. Specifically, a method for regioselectively
synthesizing unsaturated carbonyls from n-alkanes was observed. Reaction products were characterized
online during the reaction with high resolution mass spectrometry, which revealed that these reactions
occur on a sub-millisecond timescale. Efforts to scale up these reactions as well as characterization of
these reaction mixtures with other analytical methods will also be described.
27
Garett MacLean1, Jacob Shelley1
1Rensselaer Polytechnic Institute
Uranium Isotope Ratio Analysis with Solution-Cathode Glow Discharge Mass Spectrometry
The International Atomic Energy Agency (IAEA) monitors the enrichment of uranium at
production facilities by collecting and shipping samples to designated laboratories for analysis and sets
International Target Values (ITVs) for uncertainty goals to ensure the reliability of an analytical technique
for isotope-ratio measurements. Increasing restrictions on the transport of enriched uranium samples has
created a demand for rapid, on-site methods of uranium-enrichment assay. Here, a new ionization source
for mass spectrometry (MS), the solution cathode glow discharge (SCGD), is evaluated as a potential
ionization source for U-isotope ratio measurements when coupled with an Exactive Plus Orbitrap mass
spectrometer. The SCGD consists of a low-power (70 W) direct current plasma between an anode and the
surface of a flowing, conductive sample solution with ambient air serving as the discharge gas.
Preliminary optimizations have resulted in 235U/238U precisions as low as 0.09% relative standard
deviation (RSD) for a 500 part-per-billion U-solution of 0.37% 235U abundance. The precisions attained
demonstrate that SCGD-MS is capable of exceeding the IAEA’s ITVs for established techniques, and
shows great promise as a transportable ionization source for on-site isotope-ratio measurements.
28
Matthew Dellehunt1
1Rensselaer Polytechnic Institute
Mc Br Es -- Micro-climate Bio-remediation Ecological System
This project aims to remediate the Heat Island effect in New York City by deploying an Oyster
and micro-Algae Ecological System into the environment, providing cleaner air, through a CO2
absorption and bio-remediation process of the Algae. Through lower CO2 levels and evaporative cooling,
Micro-climate will be formed around each food cart and around the commissary.
This project also aims to clean and utilize the Hudson river shed to grow and produce oysters and
algae for human consumption. To do this, water bio-remediation treatment occurs to remove PCBs
through algae consumption, then is passed through pressurized barriers to the oyster habitats where
sediment and further organic material is remove, finally passing back out into the Hudson water shed as
fully cleaned water
29
Jonathan Kulwatno1, Kristen Mills1, Mihaela Skobe2, Matthew Getzin1 Ruth Griswold2
1Rensselaer Polytechnic Institute, 2Ichan School of Medicine, Mount Sinai
Tumor Growth in Vessel-Like Microchannels
Metastases account for approximately 90% of deaths associated with cancer. They are secondary
tumors that develop from the metastatic cells of a primary tumor, where the lymphatic system has shown
to be a major contributor. Here, the lymphatic vasculature can act as a conduit for the dissemination of
tumor cells, but also a niche for which tumor cells can develop within the vessel and form so called
intralymphatic tumors. In this project, we explore how the geometry and mechanical constraint as by a
lymphatic vessel contributes to the growth and morphology of such intralymphatic tumors. HCT116
human colon cancer cells were introduced and allowed to growth within a hollow microchannel made in
bioinert agarose. The concentration of agarose was adjusted to provide different mechanical stiffness that
mimicked the stiffness of healthy and diseased tissues. As a result, the stiffness of the geometric
constraint influenced the overall shape of the tumors, but did not affect the volumetric growth rate.
30
Stephanie Jennings1
1Rensselaer Polytechnic Institute
The Horrors of Transcendent Knowledge: A Feminist-Epistemological Approach to Video Games
The purpose of this presentation is to advance strategies for understanding video games from
situated perspectives. I outline a subjective, intersectional framework that draws upon feminist-
epistemological theories to call attention to ways that players may generate feminist ways of knowing
through their own playful experiences of video games.
To demonstrate this framework in action, I explicate sections of my own playthrough of From
Software’s (2015) Bloodborne. While the Dark Souls franchise—of which Bloodborne is a part—could
be critiqued as a violent masculine power fantasy, I suggest that women may find enjoyment in
Bloodborne’s violence and difficulty. I understand Bloodborne as dealing expressly with epistemological
concerns, functioning largely as a critique of traditional Western knowledge production. As such, I
suggest that women may experience the game’s violence as a symbolic language of liberatory power
against oppressive patriarchal structures.
My account of Bloodborne is just one example of how to broaden understandings of play-styles,
demonstrating a resistant channel for situated knowledge and experience. By offering insight into the
possible pleasures, desires, and experiences of playing video games as a woman, I argue that Bloodborne
reveals the horrifying consequences of the pursuit for transcendent, rational, objective—yet
hegemonically male-centered—knowledge.
31
Xiangyu Gong1, Kristen Mills1
1Rensselaer Polytechnic Institute
Cell division in multicellular tumor ellipsoids in a non-adhesive 3D environment
Mechanical stress, a key factor in the tumor microenvironment, is known to play a role in cell
division and tumor growth. Our current research aims to reveal the links between the biomechanical
environment, the force generating capability of cells, and tumor shape. Our in vitro 3D tumor models
have shown that tumor shape is a function of the stiffness of the mechanical environment. Tumors adopt
ellipsoidal shape in stiffer, non-adhesive, inert hydrogels. Similar shapes have also been observed by in
vivo studies. However, the perturbation of the tumor shape and the interplay between this shape and cell
divisions in a tumor still remain elusive. Here, our tumor growth monitoring from the single-cell level
over a week via brightfield time-lapse imaging captured the symmetry breaking moment of tumor
ellipsoid development. Furthermore, 3D time-lapse confocal imaging on a fluorescence-labeled tumor
ellipsoid embedded in agarose hydrogel over a 24-hour period allowed us to visualize and map all cell
divisions in this complex 3D shape. The preliminary results suggest a unique distribution of cell division
events in a 3D ellipsoidal tumor.
32
Ashok Williams1, Kristen Mills1, Rachel Dass1, Elizabeth Pontius1, James Nowak1, Johnson Samuel1
1Rensselaer Polytechnic Institute
Electrospinning of Hybrid Scaffolds to Mimic the Tumor Microenvironment
The extracellular matrix (ECM) provides structural, biophysical, and biologically active support
to the cells within the microenvironment. During the progression of solid tumors, the ECM is altered
through deregulated fiber growth, and increased fiber reorganization. The biomechanical interactions of
cancer cells with the extracellular matrix are of key interest when developing in vitro cancer models
because tumor behaviors are highly influenced by their microenvironments. Specific biophysical variables
are necessary to recapitulate the in vivo environment. Previous research has focused on 2D structures to
monitor cell growth, or simple hydrogel models to produce a 3D environment. We aim to produce a
fibrous hydrogel to recapitulate native ECM that physiologically and mechanically mimic the tumor
microenvironment. Tunable electrospun fibrous mats composed of polycaprolactone (PCL) were
manufactured to assess cell interactions as a preliminary step to developing 3D in vitro models. This
process of electrospinning was then used in conjunction with agarose formation to produce a uniformly
mixed fibrous hydrogel to encapsulate cells.
33
Jane Thibeault1
1Rensselaer Polytechnic Institute
Expression of Kinetically Stable Proteins in Pseudomonas aeruginosa and Staphylococcus aureus
While most proteins are susceptible to denaturants, detergents, and proteases, hyperstable or
kinetically stable proteins (KSPs) are highly resistant to such degradation and unfolding. Of particular
interest, KSPs are resistant to denaturation induced by the detergent sodium dodecyl sulfide (SDS). The
gel electrophoresis method diagonal two-dimensional (D2D) SDS-PAGE exploits this SDS-resistance and
is coupled with MALDI-TOF MS in order to explore the presence and roles of KSPs in complex
biological lysates. This study will apply the D2D SDS PAGE method to the pathogenic model systems
Pseudomonas aeruginosa and Staphylococcus aureus to further elucidate structural and functional trends
common to hyperstable proteins. Further experimentation with modified environmental conditions,
including changing growth phase, co-culturing the two systems, and altering the active respiration
pathways, will modulate transcription and ultimately the protein and KSP expression in the systems.
These modifications mimic naturally occurring growth environments for P aeruginosa and S. aureus
which may allow for additional KSP identifications not seen under the standard laboratory growth
conditions. Analysis of all the KSPs identified will advance the understanding of protein kinetic stability
and may provide information applicable to science and engineering endeavors with medical and
biotechnological relevance.
34
Amelia Peterson1, Shayla Sawyer1
1Rensselaer Polytechnic Institute
An ultrasensitive ultraviolet (UV) photodetector is created through the integration of a UV-
sensitive ZnO quantum dot (QD) layer, a highly conductive graphene channel, and a 10-
decyltrichlorosilane SAM spacer for mitigation of mobility deterioration in the graphene. The synergistic
combination of these nanocomposite materials yields excellent device performance relative to commercial
UV photodetectors, and its applications include space-to-space communications, environment monitoring,
and missile plume detection. Experimental results from our fabricated device show a high
photoresponsivity of 108 A/W, a photodetectivity of 5.1x1013 Jones at 368nm and room temperature, a
high phototransistor gain of 3x109 and a UV to visible light rejection ratio of 103. To improve upon the
overall performance of this UV photodetector, potential device and nanostructure geometries are explored
through simulation in NEMO5 and Sentaurus. The simulation setup is confirmed by comparison to
measurements of the fabricated device from published results. Generated plots include photocurrent as a
function of drain-source voltage, photoresponsivity, gain, and transient response. The effect of graphene
defects on dark current is investigated, and the relationship between graphene layer geometry and overall
device performance is explored. The results found in this work will guide the development of future
device designs and fabrication methodology for this UV sensor.
35
Robert Altman1, Xiangyu Gong1, Kristen Mills1
1Rensselaer Polytechnic Institute
Microfluidic Drop Patterning Chip
Cancer treatment relies heavily on selecting the proper cocktail of drugs specific to a patient’s
individual cancer cells. Selection of this cocktail is done by growing the cancer cells in vitro (outside of
living body) in the 2d environment of a petri dish. A 3d encapsulation of the cells would provide a more
accurate representation of the in vivo (within living body) environment. Cells grow differently in a 3d
environment than in 2d, and this difference could change how the cancer cells react to the cancer
treatment drugs. The goal of my research is to develop a method of depositing cells well aligned to a grid
and a single layer within the 3d agarose substrate to allow for automated imaging. First, to accomplish
this, a microfluidic device is used to capture the cells in the desired pattern, then the cells space above the
cells is flooded with agarose. Once covered in agarose the device is inverted allowing for the cells to
drop. By varying the curing time in relation to the mass of the captured cells, the cells can be embedded
on the same plane as well as in the array of the microfluidic device.
36
James Hu1
1Rensselaer Polytechnic Institute
Engineering Microbial Electrosynthesis in Escherichia coli for Enhanced Carbon Efficiency
Microbial electrosynthesis, a process by which electrons are supplied to microorganisms through
an electric current, allows for enhanced carbon efficiency in industrially-relevant bioprocesses.
Artificially providing reducing equivalents by supplying an electron mediator allows cells to shuttle
electrons in, increasing the carbon efficiencies and theoretical yields of chemical reactions for high value
products. This changes the stoichiometry of industrially-relevant bioprocesses that rely on redox
reactions, resulting in more efficient utilization of carbonaceous reactants.
Several organisms have been identified as being able to naturally conduct electricity; in anoxic
environments Shewanella oneidensis produces electrically-conductive nanowires to reduce metals while
organisms such as Gallionella capsiferriformans and Sideroxydans lithotrophicus have naturally occurring
metal-oxidizing pathways. Replicating these pathways in Escherichia coli would allow for the wide-
spread use of microbial electrosynthesis for enhanced industrial bioprocesses.
Creating a genetic platform for inserting the various combinations of electrosynthetic pathway
components into the microorganism is crucial for the development of a relatively straightforward
approach for optimizing electron uptake in E. coli. Novel analytical techniques will be developed to
determine the engineered organism’s electrosynthetic capabilities. The techniques, challenges, and future
work will be discussed.
37
Carlos Ivan Rivera-Gonzalez1, Diana Ramirez-Rios1,
Cara Wang1, Jose Holguin-Veras1, Joshua Schmid1
1Rensselaer Polytechnic Institute
Public Opinion Towards Crowd Deliveries in New York State
Crowd deliveries is a business model in freight deliveries that is part of the new trend of shared
economies. It matches excess vehicle capacity from the common person or crowd (who act as the courier)
with the demand of others geographically dispersed individuals who require their merchandize to be
delivered. In the last few years, there are more than 40 start-up companies in the U.S and more than 50
worldwide that use this new concept. This innovative model has shown to make urban freight more
efficient particularly in the last-mile delivery, showing potential reductions for both transportation costs
and environmental impacts. This study is intended to understand the shopping behaviors of individuals
and their acceptance, or not, of these alternate delivery services, such as crowd deliveries, and their
feasibility in accordance to today’s market conditions. Initial empirical findings in New York State
suggest that there is still some resistance in accepting Crowd Deliveries but some segments of the
population are more inclined to accept this new trend of deliveries.
38
Diana Ramirez-Rios1, Jose Holguin-Veras1, Shama Campbell1,
Lokesh Kalahasthi1, Carlos Gonzalez-Calderon1, Jeffrey Wojtowicz1
1Rensselaer Polytechnic Institute
Quantification of Freight and Service Activity Trends in Cities
The purpose of this presentation is to demonstrate the potential of freight trip generation and
service trip attraction models in studying freight and service activity (FSA) patterns for cities of various
sizes. Models that estimate freight and service vehicle trips were incorporated in a software that uses as
inputs the publically available ZIP code business patterns data for various industry sectors at ZIP code
level. Three city sizes were considered: Small, Intermediate and Large and the North American Industry
Classification System (NAICS) at 2-digit level was considered for industry type. The results shown
correspond to eight cities (two small, three intermediate, and three large) that correspond to different
ranking percentiles of population density. The cities were compared with respect to various metrics of
FSA estimates. These ZIP code level estimates are very helpful in identifying zones with high freight or
service activity. The results show that the distribution of NAICS and the size of the firms play a
significant role in the generation FSA.
39
Jennifer Rico-Varela1, Leo Q. Wan1, Kathryn Worley1
1Rensselaer Polytechnic Institute
Cellular Chirality as a New Screening Platform for Human Laterality Disorders
During early stages of pregnancy, exposure to certain pharmaceutical drugs can lead to human
laterality disorders, resulting in improper positioning and shaping of visceral organs within the body.
Heterotaxy and isomerism are the most common types of laterality disorders, and related to the
disturbance in the establishment of left-right (LR) asymmetry. The LR symmetry, also known as chirality,
is a conserved property of organisms. The LR axis is developed from the pre-establishment of the
anterior-posterior (AP) and dorsal-ventral (DV). Due to the lack of in vitro high-throughput platforms for
testing the effects of drugs during pregnancy, the underlying mechanisms of disorders are understudied.
Recently increasing evidences suggest that embryonic LR asymmetry may arise from cellular LR
asymmetry or cell chirality. Our objective is to mimic LR symmetry breaking during embryogenesis by
combining microtechnologies with the culture of human embryonic stem cells (hESCs). Herein, we
screened dozens of stem cell signaling small-molecule drugs using an in vitro platform, which
recapitulates the complexity of in vivo chiral morphogenesis in 3D at the cellular level. For this purpose,
we embedded single hESCs within a Matrigel bilayer of different concentrations (100% bottom and 2%
top layers), and exposed them to different chemicals such as regulators of JAK/STAT, GSK3, Wnt, and
TGF-beta. From our preliminary results, we observed significant changes in rotation directionality
compared to the control groups. Interestingly, these respective signaling pathways play an important role
in the establishment of embryonic LR asymmetry, demonstrating the value of in vitro screening. In
ongoing studies, we are exploring a new microfluidic approach to better recapitulate the cellular
microenvironment at which the aforementioned axes are established via morphogen gradients utilized in
embryogenesis. Such platforms can become powerful tools to not only study embryogenesis, but also to
identify teratogens for birth defects prevention.
40
Rachel Dass1, Ashok Williams1, Kristen Mills1, James Nowak1, Johnson Samuel1
1Rensselaer Polytechnic Institute
Manufacturing of 3D Fiber-Reinforced Hydrogels for Tumor Growth Studies
It is well established that tumor growth and tumor cell behaviors are significantly affected by
increased stiffness that takes place, in part due to increased fiber density. The full extent to which
microenvironmental mechanics plays a role in tumor growth and progression is still unknown. Current
models to study these behaviors are limited to 2D or include only the fiber or gel portion of the ECM. In
order to isolate the effects of the fiber-gel composite ECM morphology and mechanics, we have
developed a 3D fiber-reinforced hydrogel consisting of biocompatible polymer fibers to study the growth
of cancerous tumors. By varying process parameters, we can create 3D fiber-reinforced hydrogels that
mimic the morphology and mechanics of healthy and diseased tissue.
41
Dhruv Patel1
1 Rensselaer Polytechnic Institute, Scientific Computation Research Center
It is a well known fact that benign tumors tend to be mechanically homogeneous, while malignant
tumors are more heterogeneous. Likewise, benign tumors are elastically linear, whereas malignant tumors
are non-linear. Traditional elastography techniques use these differences to diagnose disease and/or
classify tumors. However, these techniques require the solution of an inverse elasticity problem, which is
quite expensive, and often difficult to solve. Inspired by the recent developments in computer vision and
deep learning, we propose a different strategy and use deep neural networks to classify the tumor based
on its mechanical properties without solving an inverse problem. We train a Convolution Neural Network
(CNN) on in-silico displacement data for this classification task. We also investigate the effectiveness of
transfer learning in this context to mitigate the problem of non-availability of sufficient labeled data in
medical imaging domain.
42
Manish Bhat1, Steven Cramer1, Akshat Mullerpatan1, Anurag Rathore2
1Rensselaer Polytechnic Institute, 2Indian Institute of Technology, Delhi
Continuous Precipitation of Antibodies
Since starting out as an undergrad, I have worked on making drugs that can cure cancer cheaper.
The drug, I am working on is mAb( monoclonal antibody). 70% of the cost is due to purifying it. I am
trying to replace a standard method used currently called Protein-A chromatography with continuous
precipitation. It is cheaper but, can also achieve the same level of purity. This sounds awesome, what is
the catch? Protein-A chromatography has been done for almost 4 decades. It is a very reliable method to
purify drugs. I need more data to fully confirm the high level of purity of continuous precipitation.
Ultimately, the safety of the patient matters the most, and thus reliability is key. This is why, I have come
to RPI to continue my research into continuous precipitation under Professor Cramer who has done some
really fascinating research in the field of drug purification.
43
Anirban Chandra1, Fan Yang1, Yu Zhang1, Onkar Sahni1, Assad Oberai1, Mark Shephard1
1Rensselaer Polytechnic Institute
Solving Phase change problems using Unstructured Finite Elements
Interfacial phase-change processes such as evaporation/condensation of a liquid (or combustion
of a solid) are commonplace in several engineering applications. Numerical modeling of such physical
phenomenon necessitates some special attention because of large density ratio over phases, discontinuous
fields at the interface and rapidly evolving geometries. Here we present a mathematically consistent and
robust computational approach to address these issues. Stabilized finite element methods on mixed
topology unstructured grids is utilized for solving the compressible Navier-Stokes equations. Flux jump
conditions derived from conservation laws at the interface are handled by using discontinuous
interpolations, while the continuity of temperature and tangential velocity is ensured using a penalty
parameter. The Arbitrary Lagrangian-Eulerian (ALE) technique is utilized to explicitly track the interface
motion - the mesh at the interface is constrained to move with the interface while elsewhere in the
domain it is moved using the linear elasticity analogy. In addition, mesh modification is done when the
mesh becomes too distorted.
44
Zhongqian Lin1
1Rensselaer Polytechnic Institute
The Structural Study of the HINT Domain of the Hedgehog Protein
Hedgehog signaling pathway is a developmental pathway that is essential for adult stem cell
maintenance. The malfunction of this pathway is associated with a variety of cancer such as prostate
cancer and basal cell. In this study, we purified a mutant segment of the Hedgehog ligand precursor and
study its structure using Nuclear Magnetic Resonance. Studying the structure of the protein's potential
active site would allow us to learn about the detailed mechanism of the pathway activation and provide a
new approach to understand cancer development.
45
Syed Islam1, Ji Jiang1, Qiaobei Dong1, Huazheng Li1, Miao Yu1
1Rensselaer Polytechnic Institute
High Temperature Separation of H2/N2 using SAPO-34 Membranes
Synthesized on Ceramic Hollow Fibers
Zeolite membrane has drawn tremendous interest in gas and liquid separations due to its well-
defined pores and channel structure. With the advantages of high chemical, thermal and mechanical
stability, zeolite membranes could be used in harsh environment such as high temperature and pressure.
In this study, SAPO-34 membranes were successfully synthesized on the outside of ceramic hollow fibers
by secondary growth method. The influence of synthesis parameters, such as precursor composition, seed
particle size, morphology, concentration and stabilizer concentration in the seed suspension, and seeding
conditions, and of pore size of support, on the separation performance of SAPO-34 membranes was
studied in detail. The results indicated that high quality SAPO-34 membranes with thickness of < 5 µm
could be achieved by using high aspect ratio zeolites as seeds. The as-synthesized membranes exhibited a
high H2 permeance of 2.9×10-7 mol/(m2·s·Pa) and H2/N2 separation selectivity of 19 at 400 oC and
pressure drop of 100 psig. Further, the membranes were stable at temperature up to 400 oC and pressure
drop up to 100 psig for > 2.5 h, which make it very suitable for industrial applications such as the
decomposition of NH3 for the production of high purity H2.
46
Michael Jenkinson1, Jeffrey Banks1, William Henshaw1, Jordan Angel1, Donald Schwendeman 1
1Rensselaer Polytechnic Institute
A High-order Accurate Scheme for Maxwell's Equations with a Generalized Dispersion Model
A high-order accurate scheme for solving the time-domain Maxwell's equations with a
generalized dispersion model is described. Maxwell's equations are solved in second-order form for the
electric field. General dispersion models are treated with the addition of one or more polarization vectors
which are coupled to the electric field and its time-derivative through a set of second-order ordinary
differential equations (the so-called auxiliary differential equation (ADE) approach). Single-stage three-
level space-time schemes are developed for both second-order and fourth-order accuracy in space and
time which lead to very efficient schemes with a large CFL "one'' time-step. The equations are discretized
in space using finite-difference and conservative finite-difference approximations. Since the equations are
in second-order form it is straight-forward to discretize the equations in a compact manner on collocated
grids without the need for staggering. Composite overlapping grids are used to treat complex geometry
with boundary conforming grids. A high-order upwind dissipation is added to the scheme to ensure a
robust and stable approximation on overlapping grids. Numerical results in two and three space
dimensions confirm the accuracy and stability of the new schemes.
47
Antwane Mason1
1Rensselaer Polytechnic Institute
Reuse Opportunities in Software Quality Assurance
Our research goal is to lower time and effort required to perform both testing and formal
verification, two important quality assurance (QA) activities. We wish to achieve this goal by developing
theory, tools, and automation for reuse of software artifacts and processes between both QA activities. To
this end, we explore existing software artifacts and processes that can be reused between the two
activities. We also explore a branch of mathematics called category theory to serve as a tool for theory
development.
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