Celebrating Birthdays of DPI Professors and Students!

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Dear All

Please join us for our next exciting seminar on Friday, November 9th at 10:30 a.m. in the DPI conference room.

Our presenter will be: Tim Ombrello 5th Year Ph.D. Student Princeton University

TITLE: Kinetic Ignition of Counterflow Diffusion Flames by Plasma-Activated Ultra-Lean Pre-Mixtures

Abstract:

Plasma enhanced combustion has recently attracted much attention because of its potential to decrease ignition delay times by producing key radicals and excited species. Unfortunately the mechanisms of plasma enhancement for a combustion system are not fully understood because of the complex and highly coupled interaction. This presentation will discuss the current work on kinetic ignition enhancement of hydrogen-air diffusion flames by a non-equilibrium plasma discharge of ultra-lean pre-mixtures. The development of a simplified and well defined counter flow burner integrated with a plasma system was studied experimentally. Measurement and comparison of the ignition temperatures provided a basis for understanding the kinetic enhancement pathways for ignition by plasma discharge of air with and without plasma activation and small concentrations of hydrogen and methane addition to the air. With plasma discharge of the air, the ignition temperatures were significantly decreased when compared to only heated air. The primary species that caused the ignition enhancement was NOx by catalyzing the inactive HO2 radical to OH. The addition of hydrogen and methane to the air upstream of the plasma mitigated the effect of NOx.  

Hope you are able to attend

Best regards,

     Yelena Alekseyeva

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Dear Everybody,

Please join us for this exciting seminar on Friday, October 26th at 10:30 a.m. in the DPI conference room.

Our presenter will be: Dr. Bahrad Sokhansanj, Assistant Professor, Drexel University, School of Biomedical Engineering  

TITLE: Engineering Human DNA Base Excision Repair.

ABSTRACT: 

Hope you are able to attend 

Best regards,

                                                 Yelena Alekseyeva

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Dear All,

Our next DPI seminar will be held on Thursday, June 7th at 10:00 p.m. in the DPI conference room. 

Our presenter will be: Dr. Yurii Mukhin

The title of the presentation will be: "Intracellular Signaling: Experimental aspects of signal transduction"  

Abstract:

The purpose of this presentation is to let you have a brief glance at some important intracellular signaling events.

Here, we describe in simplified terms several signaling cascades in various types of cells including vascular smooth muscle and kidney cells. The discussion is focused on experimental issues of research from a physicist's point of view. We use examples from our published papers and from our recent unpublished work as well.

See you all on Thursday, June 7th.

Best regards,

                                Yelena Alekseyeva.

Dear Students, Colleagues and Friends,

You are invited to attend the next DPI seminar this Thursday, May 31st at 10:00 p.m. in the DPI conference room. 

Our presenter will be: Avijit Ghosh, Ph.D. Asst. Professor, Drexel University, Dept of Physics.

Title of Presentation: From Simulation to Therapy: Perturbations in the MAPK Pathway

ABSTRACT:

The MAPK pathway mediates signaling of growth hormones and cytokines and participates in regulating both cellular proliferation and death. Mutations in proteins that are members of the MAPK pathway have been detected in 48% of tumors in small cell lung cancer, 50% of colon cancers, 75% of pancreatic cancers, and 27% of breast cancers, among others. Using the MAPK pathway as a backdrop, I will present some of the work in our group on understanding, quantitatively, cell signaling in general and moreover present how understanding the underlying biochemistry of the cell may be used to not understand disease progression but prevention.

Hope you are able to attend.

Sincerely,

Yelena Alekseyeva.

Dear Students, Colleagues and Friends,

You are invited to attend the next DPI seminar this Thursday, May 17th at 10:00 a.m. in the DPI conference room.

Our presenter will be: Tanvir Farouk.

Title of Presentation: "Simulations of Atmospheric Pressure Microplasma"

Abstract: 

Atmospheric pressure glow discharges are attractive for a wide range of material-processing applications largely due to their operation flexibility afforded by removal of the vacuum system. Atmospheric pressure micro glow discharge of the cold type has been generated in our laboratory. Detailed numerical simulations and experimental studies were conducted to characterize a direct current hydrogen discharge for a pin plate electrode configuration having an inter electrode separation distance of 400 mm. A self consistent two-dimensional hybrid model was developed to simulate the atmospheric pressure direct current (DC) hydrogen micro discharges. The discharge simulation model considered consists of the momentum and energy conservation equations for a multi-component gas mixture, conservation equations for each component of the mixture (electrons, ions, excited species and neutrals) and state relations. The model uses a drift – diffusion approximation for the electron and the ion fluxes. The species considered include H, H2, H+, H2+, H3+ , H2*, H2 v = 1 and the electrons. The electric field is obtained from the solution of the Poisson’s equation. Temperature predictions suggested the discharge to be non-thermal non-equilibrium discharge. Numerical simulations and experimental measurements indicated some of the key features of a normal glow discharge: a flat voltage current characteristics and a constant cathode current density. Predictions from the model compares favorably well to the experimental measurements. The model is being further extended to predict the physico-chemical processes of a methane-hydrogen plasma used for thin-film deposition, where trace amount of methane is mixed with hydrogen gas.  

Hope you are able to attend.     
  
Sincerely,

        Yelena Alekseyeva.  

Dear Everybody,

We will be having our next DPI seminar. Please see below for more details.

Presenter: David Staack.
Date: Thursday, April 26th, 2007 at 10:00.
Location: Drexel Plasma Institute Conference Room, HESS building # 117.

Title: Thin film deposition using atmospheric pressure plasma enhanced
chemical vapor deposition

Abstract: It is desirable to use atmospheric pressure plasmas for thin film material processing because of the lower facility costs than vacuum processing and the possibility to operate continuous rather than batch processes. However, several major concerns exist in attempting to use atmospheric pressure plasmas for the plasma enhanced chemical vapor deposition (PECVD) of thin films. These include: 1) the creation of stable non-thermal plasma discharges 2) discharge uniformity and size, and 3) particle formation. In this research we address these issues with reference to the use of DC and RF microplasmas for the atmospheric pressure PECVD
(AP-PECVD) of hydrogenated amorphous carbon films (a-C:H) from H2, and CH4 precursors. Through voltage, current, and spectroscopic characterization of the microplasmas we have found the discharges to be stable, non-thermal, normal glow discharges which are density scaled versions of the normal glow discharges used in low pressure plasma processing. These discharges are susceptible to the ionization overheating instability. Analysis of the stability criterion for these microplasmas reveals that they can be stabilizes through modification of the external electrical circuit or selection of appropriate operating frequency, and experimentally we have used these results to broaden the regime of stable operation. The creation of stable discharges was one obstacle in preventing particle formation and creating thin films. The other obstacle was careful control of the gas discharge temperature to prevent the activation of chemical pathways which lead to particle formation. Through optical emission spectroscopy we are able to measure the discharge temperature and find that the use of atomic buffer gases in the precursor gas mixture reduces the operating temperature and lead to regimes of particle free thin film deposition. The deposits vary in composition from polymer to diamond like to graphitic. The film properties were analyzed using Raman and FTIR vibrational spectroscopy and hardness testing.

Hope you are able to attend.     
  
Sincerely,

        Yelena Alekseyeva

Dear all,

We will be having our next DPI seminar.  Please see below for more details.

Presenter: Danil Dobrynin.
Date:         Thursday, April 12th, 2007 at 10:00. (Please note that DPI Seminar starts at 10:00am NOT 11:00am)
Location:   Drexel Plasma Institute Conference Room, HESS building # 117.

Title: Design and Medical Applications of Microplasmatron.

Abstract: Direct plasma and plasma flows have a lot of applications in medicine and biology based on a wide spectrum of phenomena which occur while plasma components interact with biological objects. At the Laboratory of Microplasma Techniques of Petrozavodsk State University we have created a plasma device which allows generating low temperature plasma flows for medical applications. A series of in vitro and in vivo experiments give ground to affirm that cold plasma has strong bactericidal action accompanying by minimal and reversible changes of biological tissue.
The device design and plasma experiments with biological objects will be discussed.

Hope you are able to attend.     
  
Sincerely,

        Yelena Alekseyeva.
       

Dear all,

We will be having our next DPI seminar.  Please see below for more details.

Title: DBD Plasma Interaction with Living Tissue

Presenter: Greg Fridman
Date:      Thursday, March 15th, 2007 at 3:30.
Location:  Drexel Plasma Institute Conference Room, HESS building # 117.

Abstract: Presentation will cover recent experimental results regarding:

1. Phenomenology of plasma interaction with living tissue;

2. Biological and physical mechanisms of this interaction;

3. Discharge physics optimization;

4. And the applications, i.e. skin sterilization, treatment of skin diseases, gastroenterology, etc.

Hope you are able to attend.

Yelena.     

Dear Students, Colleagues and Friends,

We will be having our next DPI seminar.  Please see below for more details.  

Title of Presentation: COMPARISON OF DIRECT AND INDIRECT APPLICATION OF NON-THERMAL ATMOSPHERIC PRESSURE DIELECTRIC BARRIER DISCHARGE PLASMA TO  TISSUES AND CELLS

Presenter:   Greg Fridman

Date:            Thursday, March 1st, 2007 at 3:30.

Abstract:      Direct and indirect influence on micro-organisms of non-thermal atmospheric pressure Dielectric Barrier Discharge in air is compared in terms of bacteria inactivation rates.  It is demonstrated that direct influence of the   plasma, where charged particles contact bacteria directly, produces inactivation much faster than the indirect treatment, where plasma afterglow is delivered to the bacteria with a gas flow through the plasma region.  This leads to an important conclusion that the effect of charged particles in plasma plays the essential role in interaction with living organisms, although synergy with longer living active molecules and atoms as well as UV radiation generated in plasma and at the surface of tissue may also play a role in inactivation.

Hope you are able to attend.

Yelena.

Dear Students, Colleagues and Friends,

You are invited to attend the next DPI seminar this Thursday, February 15th at 3:30 p.m. in the DPI conference room.

Title of Presentation: "Modeling, Design and Testing of Biological Systems"

Our presenter will be: Dr. A. Julius 

Abstract:

I will motivate the talk by presenting biological systems as engineering systems. Advances in systems biology has brought about synthesis aspect into cellular biology, which was a largely analytic field. Deeper understanding of genetic regulation systems has enabled scientists to design genetic modules and circuits similar to the ones that were done with solid state electronics.

I will then proceed with my recent work, modeling and feedback control design of a biological system, the lactose regulation system of E. coli.

Rigorous modeling enables us to capture important phenomena that cannot be captured by some of the existing models of the same system. In addition to that, I will present a multilevel modeling paradigm that acts as an interface between the modeling/analysis world and the design/synthesis world.

I will conclude the talk by presenting some future directions, where similar ideas can be applied to the design and analysis of self assembly systems and control of a massive group of robots.

Bio: Agung Julius is a postdoctoral researcher at the GRASP Lab, University of Pennsylvania. He obtained his MSc and doctoral degree, both in Applied Mathematics, from Universiteit Twente (NL), in 2001 and

2005 respectively, under the scholarship provided by the Dutch National Science Foundation and the Dutch National Aerospace Laboratory. He also has a B.Eng degree in Electrical Engineering, from Institut Teknologi Bandung in 1998.

Dr. Julius' research interests lie in the intersection of systems and control theory, systems biology and computer science.

Hope you are able to attend. 

Yelena Alekseyeva.

Ladies and gentlemen,

We will be having our DPI seminar this Thursday, February 1st at 3:30 p.m. in the DPI conference room.  

The program will be as follows: Characterization of Continuous and Pulsed Dielectric Barrier Discharge Regimes in Air, Oxygen, Nitrogen, Helium, and Argon.  Part 2: Power analysis.

Our presenters will be: Y. Yang and M. Cooper 

Hope you are able to attend. 

Yelena Alekseyeva

Dear Students, Colleagues and Friends,

You are cordially invited to attend the next Biomed Seminar of the Winter term on "Vascular Basement Membrane Memory of Acute Hyperglycemic Events" by Alisa S. Morss, Ph.D. scheduled for Friday, January 26, 2007 at 4:00pm in 109 Matheson (Matheson Hall is located at 32nd and Market Streets.)

To attend the webcast, please visit:
Link: www.biomed.drexel.edu

Dear colleagues,
On Thursday, January 18, at 12:00 pm we will be have presentation (see the information below).

Title: Characterization of Continuous and Pulsed Dielectric Barrier Discharge Regimes in Air, Oxygen, Nitrogen, Helium, and Argon.

Part 1: Power analysis.

Presenters: Y. Yang and M. Cooper 

Description: Results and comparison of Dielectric Barrier Discharges (DBD) in continuous and pulsed regimes will be presented. Different streamer structures are observed using different gases, including air, argon, oxygen, nitrogen and helium.   Comparison between different flow rates will be discussed.

Place: DPI Conference Room.

Dear colleagues,

This week we have DPI seminar on Thursday, December 14, at 3:30 at DPI conference room.
We have a visitor from the Michigan State University, Professor Tonghun Lee, who will make presentation 'Strategies for UV Nitric Oxide LIF Imaging in High-Pressure Combustion Systems'

See you on Thursday.
Alexander Gutsol

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College of Engineering Presents

CoE Discovery Workshop

Date: Wed., November 15, 2006
Time: 1:00 pm
Place: Bossone Auditorium

more info (PDF)

Dear colleagues,
On Friday, November 10, at 4 pm we have DPI seminar (see the information below).
You are welcome.
Alexander Gutsol

Presenter: Moogega Cooper
Title: Sterilization of Spacecraft Materials and Extraterrestrial Samples Using Atmospheric Pressure Cold Plasma

Description: This presentation is an overview of a DPI NASA-funded project whose goal is to understand non-thermal mechanisms of sterilization caused by biological plasma species that do not harm the spacecraft or its payload of extraterrestrial samples. Highlighted topics include past research and future pursuits toward achieving the project goal.

Place: DPI Conference Room

Dear colleagues,
This Friday, October 20, instead of our regularly scientific seminar, you are invited to the oral PhD candidacy exam of Michael Gallagher. He will talk about his work related to air sterilization using plasma.
The exam will take place at MEM Seminar Room at 12.00 See you there, Alexander Gutsol

New Course “Applied Thermal Plasmas”

for undergraduate students MEM 380/001, CRN 24353

for graduate students MEM 800/002, CRN 24354

instructor: Professor Alexander Fridman

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Dear colleagues,

We are starting our Fall term scientific seminars. The first seminar will take place this Friday, October 6, at 4 pm, at DPI Conference room (Hess Lab). You are welcome.
Our speaker will be our former graduate student Francis McIntire Haas.
His 30-45 minutes talk will be about the work that he did for his MS Thesis, see the abstract below.
See you there,
Alexander Gutsol

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