Dr. Ashok Kumar

• Office: ENB252
• Phone: 813-974-3942
• Fax: 813-974-3612
• E-mail: akumar@eng.usf.edu

Dr. Rakesh Joshi

• Office: ENB 261B
• Phone: 396-9353
• Fax:
• E-mail: joshi@eng.usf.edu
• Webpage: http://joshinano.googlepages.com/
• Short Bio: Rakesh K. Joshi received his Ph.D. degree in Physics from the Indian Institute of Technology Delhi in 2004. He worked as a postdoctoral fellow at the Institute for Nanostructure and Technology, University of Duisburg in Germany and Nano High Research Center at Toyota Technological Institute in Nagoya, Japan. He has published over 35 journal articles in the field of Nanomaterials and Sensors. Dr. Joshi is an associate editor for the Journal of Nanomaterials (JNM) and has edited three special issues for JNM.

Humberto Gomez (Ph.D. Student, Mechanical Engineering)

• Office: ENG 119B
• Phone: 396-9351
• Fax:
• E-mail: hagomez2@mail.usf.edu
• Short Bio: Humberto Gomez is a PhD student in the Department of Mechanical Engineering, University of South Florida. He received his MS and BS from Universidad Del Norte in Colombia. His research interests include nanocrystalline diamond films, mechanical and tribological properties of diamond films, and machining performance of diamond coated cutting tools.

Qiang Hu (Ph.D. Student, Mechanical Engineering)

• Office: ENG 119B
• Phone: 396-9351
• Fax:
• E-mail: qhu@mail.usf.edu

Farah Alvi (Ph.D. Student, Electrical Engineering)

• Office: ENG 119B
• Phone: 396-9351
• Fax:
• E-mail: falvi@mail.usf.edu
• Short Bio: Farah Alvi is PhD student working on ZnO nanowires for photovoltaic applications. She received her MSEE in 2008 from the University of South Florida. Farah is recipient of Best Poster Award at FLAVS-2009.

Pedro Villalba (Ph.D. Student, Chemical & Biomedical Engineering)

• Office: ENG 261B
• Phone: 396-9353
• Fax:
• E-mail: pvillalb@mail.usf.edu

Jessica Weber (Ph.D. Student, Mechanical Engineering)

• Office: ENG 119B
• Phone: 396-9351
• Fax:
• E-mail: jess@mail.usf.edu

Mikhail Ladanov (Ph.D. Student, Electrical Engineering)

• Office: ENG 118C
• Phone: 396-9353
• Fax:
• E-mail: mladanov@mail.usf.edu

Ahmad Aslam (Ph.D. Student, Electrical Engineering)

• Office: ENB 150
• Phone: 974-4101
• Fax:
• E-mail: anaslam@mail.usf.edu

Joe Bonivel (Ph.D. Student, Mechanical Engineering)

• Office: ENB 150
• Phone: 974-4101
• Fax:
• E-mail: jbonivel@mail.usf.edu

Supriya Ketkar (Ph.D. Student, Electrical Engineering)

• Office: ENB 249
• Phone: 396-9353
• Fax:
• E-mail: sketkar@mail.usf.edu

Denis Kitenge (M.S. Student, Mechanical Engineering)

• Office: ENG 119B
• Phone: 396-9351
• Fax:
• E-mail: dkitenge@mail.usf.edu

Nidhi Joshi (M.S. Student, Material Science and Engineering)

• Office: ENG 119B
• Phone: 396-9351
• Fax:
• E-mail: njoshi3@mail.usf.edu

Daniel Perez

• Office: ENB 150
• Phone: 974-4101
• Fax:
• E-mail: deperez@mail.usf.edu
• Research work summary: During the research experience, a program that read and stored the changes of resistance in time was developed using the National Instrument’s LabView software. The purpose of the program is to measure the changes in the conductivity of materials in presence of various gases while the temperature was raised or lowered. The gas goes through a chamber, which is connected to a heater. A determined voltage is applied to the film material. A Two probe measurement system is connected to the chamber through connecting wires. The other ends of the wires are plugged in the input of a GPIB sourcemeter Keithley 2400. The sourcemeter provides a determined voltage as an input, and shows the values of the resistance in ohms as an output in the display. The first objective of the developed program is to create communication between the sourcemeter, which works as an interface, and the computer. When this is set, the program must show the changes of resistance in time and store the data at given time intervals as the temperature of the chamber increases or decreases. LabView is a powerful software that offers a several options which allow users to connect physical external instruments to the computer and perform a series of tasks. In order to create a connection between the measured values and the computer, a VI (voltage- current) file was created. VI files are based on block diagrams which graphically show the elements and connections that are used in a determined file to perform a desired task. For the given objective of measuring changes of conductivity in time, the input of the VI file was set as the output given by the sourcemeter. When the program runs, a loop created in the block diagram stores the measurements given by the sourcemeter repetitively. The timing for each measurement is determined by the user. The GPIB interface is connected to the computer via a PCMCIA card, and certain drivers are necessary to have a proper initialization of the sourcemeter. The drivers, as well as the software libraries for the sourcemeter, were found in the National Instruments web page. The front panel displays graphically the changes of resistance with time. Figure 1 shows how the front panel looks like.

Alejandra Vega

• Office: ENB 150
• Phone: 974-4101
• Fax:
• E-mail: avega2@mail.usf.edu
• Research work summary: Alejandra has been trained on the Radiometer Analytical Electrochemical Potentiostat and Voltalab 40 Software. She can perform:
  • -cyclic voltammetry
  • -electrochemical impedance spectroscopy
  • -prepare chemical solutions of different molarities
  • -attach carbon nanotubes onto glassy carbon electrodes
  • -chemicallly attach single-stranded DNA to carbon nanotubes
  • -hybridize complimentary target strand DNA
  • -perform other DNA chemistry
  • -develop a biosensor for selectively detecting DNA
  • -analyze electrode performance

Connie Bell

• Office: ENB 150
• Phone: 974-4101
• Fax:
• E-mail: clbell2@mail.usf.edu
• Research work summary: The purpose of the last semester’s research was to optimize the new Hot Filament Chemical Vapor Deposition (HFCVD) assembly to achieve the highest possible quality diamond films on silicon substrates. Initial depositions were made according to manufacturer’s instructions. Later, variables such as feedstock gas ratios, seeding process, electrode voltage, and deposition time were adjusted to improve film quality, with emphasis on minimizing the films’ graphite content. These later samples were compared via Raman spectroscopy and Atomic Force Microscopy to the initial samples to determine if significant improvement in film quality had in fact been obtained. Careful records were kept regarding the deposition parameters for each specimen, so that later comparisons would reveal the optimal seeding treatments and settings for the machine. As work proceeded and refinements were made, a customized set of procedural guidelines was developed to augment the manufacturer’s manual, incorporating the methods that the semester’s experiments had proven most effective. It is hoped that these refined guidelines will prove useful in further optimizing the HFCVD techniques for alternative substrate materials, culminating in a study of cutting tools coated with microcrystalline versus nanocrystalline diamond films. With several depositions completed, the focus shifted to sample characterization and comparison. As previously state, two methods were employed to characterize the samples, the first being Raman spectroscopy. The optimization efforts for the HFCVD machine resulted in the successful deposition of an MCD quality film on a silicon substrate, as evidenced by visual inspection of the Raman spectra and the AFM images. The MCD film was obtained with convenient slurry seeding treatment and shorter deposition time. Extending deposition time would likely increase the intensity of the MCD peak in the Raman spectrum and increase film thickness. Documentation of the semester’s proceedings led to the successful compilation of supplemental procedural guidelines, which will serve as a platform for expanded optimization efforts, to include additional substrates such as cutting tools. Additional optimization efforts could also focus on the deposition of NCD films, with an aim to compare the performance of MCD-coated cutting tools to those coated with NCD.