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FW: Seminar Notice for Aline M. Elquist MS Final Exam. Seminar, Thursday, June 27, 12:00 p.m., in HAMP G212; Exam same day at 11:30, in HAMP G212. " Instantaneous Antimicrobial Susceptibility Testing Using Piezoelectric Sensors"
by Coar, Stacey L 26 Jun '19

26 Jun '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Instantaneous Antimicrobial Susceptibility Testing Using Piezoelectric Sensors" By Aline M. Elquist Purdue MSE MS Final Exam Advisors: Professor Na Lu and Professor Rodney W. Trice ABSTRACT Rapid determination of drugs effective against bacterial strains is critically important to stopping further spread of an infection and reducing antibiotic resistance. Antimicrobial susceptibility testing (AST) is done to determine what type of antibiotic and what concentration will be effective in treating an infection. Current, growth-dependent, AST methods are reliant on the growth rate of the bacteria and can take several days to several weeks to get results. A piezoelectric plate sensor can be used to measure an instant change in the minute physiological stresses of the bacteria cells when they are exposed to an effective concentration of antibiotic. This work aims to investigate the feasibility of piezoelectric plate sensors used for instantons AST (iAST) results and develop a road map for implementation of this technology into a clinical lab setting. Four Clinical and Laboratory Standards Institute (CLSI) quality control strains of bacteria were tested with a wide range of antibiotics from various drug classes using the piezoelectric sensor. Results were obtained within 30 minutes and compared to standard of care AST methods used in clinical labs, and CLSI prescribed ranges for each strain of bacteria. Aside from bacteria, mycobacteria and fungi were tested using the piezoelectric plate sensor to show this technology can be extended to categorizing various microorganisms. This thesis will also discuss a roadmap to fabricate more scalable sensors, and challenges associated with the different sensor designs. Date: Thursday, June 27, 2019 Time: 12:00 PM Place: HAMP G212

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Workshop starting today on Diffusion in Solids with an Emphasis on Multicomponent Diffusion
by Coar, Stacey L 24 Jun '19

24 Jun '19

[cid:image002.jpg@01D52A7C.3F4E6030] Stacey Stacey Coar Secretary/Development Assistant School of Materials Engineering Purdue University Neil Armstrong Hall of Engineering 701 West Stadium Ave. Room 2300 West Lafayette, IN 47907 765-494-4100 scoar(a)purdue.edu<mailto:scoar@purdue.edu>

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Seminar Reminder for Nelyan López Pérez's Ph.D. Final Exam. Seminar Monday, June 24, at 10:30 a.m., in ARMS 1028. Exam same day at 11:30 a.m., in ARMS 2237. “Detection of Early Stages of Degradation on PPTA Fibers Through the Use of Positron Annihilati
by Son, Rosemary E 21 Jun '19

21 Jun '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR “Detection of Early Stages of Degradation on PPTA Fibers Through the Use of Positron Annihilation Lifetime Spectroscopy” By Nelyan López Pérez Purdue MSE Ph.D. Final Exam Advisor: Professor John A. Howarter ABSTRACT High-performance fibers used for ballistic protection are characterized by having outstanding mechanical properties such high modulus and strength. These mechanical properties are granted by the fiber’s chemical and physical structure as well as their high degree of orientation. Twaron fibers are one of the most commonly used fibers on soft body armors such as bulletproof vests. They are made from poly (p-phenylene terephthalamide) (PPTA), a rigid-rod and highly crystalline polymer. Although these fibers are crystalline and have great mechanical properties, their performance can decrease when they are exposed to different degradation factors. Free volume is the unoccupied space between the polymer molecules. It is responsible for characteristics such as diffusion and viscosity. Hence, the free volume changes as the polymer degrades. This thesis focuses on the effects of sonication, pH changes, and sweat on the free volume of PPTA fibers. A non-destructive technique known as positron annihilation lifetime spectroscopy (PALS) was used to measure the free volume in PPTA. Changes in the free volume of fibers degraded under different conditions were compared to their mechanical performance. Degradation in DI water, pH 4 and pH 10 aqueous solutions was conducted for 10 weeks at 80oC. Sweat degradation of PPTA fibers was also conducted for 10 weeks at 25oC, 50oC, and 100oC. Fibers degraded in pH4 and sweat solutions had greater loss of mechanical performance and changes in the free volume. PALS was able to detect changes in the nanostructure of PPTA fibers at early stages of degradation. This data was supported by mechanical tests and is complementary to other characterization techniques such as small angle X-ray scattering (SAXS). Results of this research are a stepping stone for future studies on lifetime predictions of bulletproof vests and the development of the next generation of soft body armors. Date: Monday, June 24, 2019 Time: 10:30 A.M. Place: ARMS 1028

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FW: Sandia Truman and Hruby Fellowship Announcement Requires US Citizenship
by Son, Rosemary E 18 Jun '19

18 Jun '19

Please share the following opportunities with your PhD students who recently graduated or will have graduated by October 2020. US Citizenship Required. Deadline November 1, 2019. Begin forwarded message: From: "Hoover, Marcey" <mlhoove(a)sandia.gov<mailto:mlhoove@sandia.gov>> To: "Chiang, Mung" <chiang(a)purdue.edu<mailto:chiang@purdue.edu>>, "Crawford, Melba M" <mcrawford(a)purdue.edu<mailto:mcrawford@purdue.edu>>, "Hacker, Thomas J" <tjhacker(a)purdue.edu<mailto:tjhacker@purdue.edu>> Cc: "DeLaurentis, Dan (External Contact)" <ddelaure(a)purdue.edu<mailto:ddelaure@purdue.edu>>, "Patel, Kamlesh D" <kdpatel(a)sandia.gov<mailto:kdpatel@sandia.gov>>, "Rasmus, Joel A." <jrasmus(a)purdue.edu<mailto:jrasmus@purdue.edu>> Subject: Sandia Truman and Hruby Fellowship Announcement Mung and Melba, Sandia National Laboratories is beginning its campaign to attract qualified candidates for the Harry S. Truman Fellowship and Jill Hruby Fellowship in National Security Science and Engineering. The deadline for applying is November 1, 2019. Attached are flyers that can be shared, encouraging qualified individuals to apply. The Fellowships are three-year appointments. Recipients conduct independent research that supports Sandia's national security mission; the Hruby Fellows also participate in a leadership development program that will prepare them for career advancement in their field. Please encourage your top PhD students in science or engineering to apply. Please share this information with PhD students, deans, department chairs, faculty, research center directors, graduate studies offices, fellowship offices, and professional societies. I am also sending this information to Dean Wolfe and Dean Bertoline, and am copying CERIAS (Joel Rasmus) and iGSDI (Dan DeLaurentis) on this email. Fellows may work at either principal Sandia location, Albuquerque, NM or Livermore, CA. The salary is $111,200. Candidates must be able to obtain a security clearance, which requires US citizenship, and be seeking their first national laboratory appointment. They must have been awarded a PhD within three years at the time of application or will have completed all PhD requirements by commencement of the appointment (October 2020). Our web sites provide additional information on steps required to apply: Truman Fellowship: http://www.sandia.gov/careers/students_postdocs/fellowships/truman_fellowsh…; contact Yolanda Moreno (ymoreno(a)sandia.gov<mailto:ymoreno@sandia.gov>) Hruby Fellowship: http://www.sandia.gov/careers/students_postdocs/fellowships/hruby_fellowshi…; contact Kelly S. Collins (ksmithc(a)sandia.gov<mailto:ksmithc@sandia.gov>). Thanks in advance for your help in sharing these opportunities. Marcey ******************************************* Marcey Hoover, PhD Director, Quality Assurance Sandia National Laboratories P.O. Box 5800 MS-0469 Albuquerque, New Mexico 87185 Office: 505-844-9424 Mobile: 505-803-1796 Email: mlhoove(a)sandia.gov<mailto:mlhoove@sandia.gov> *******************************************

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Seminar Notice for Aline M. Elquist MS Final Exam. Seminar, Thursday, June 27, 12:00 p.m., in HAMP G212; Exam same day at 11:30, in HAMP G212. " Instantaneous Antimicrobial Susceptibility Testing Using Piezoelectric Sensors"
by Son, Rosemary E 18 Jun '19

18 Jun '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Instantaneous Antimicrobial Susceptibility Testing Using Piezoelectric Sensors" By Aline M. Elquist Purdue MSE MS Final Exam Advisors: Professor Na Lu and Professor Rodney W. Trice ABSTRACT Rapid determination of drugs effective against bacterial strains is critically important to stopping further spread of an infection and reducing antibiotic resistance. Antimicrobial susceptibility testing (AST) is done to determine what type of antibiotic and what concentration will be effective in treating an infection. Current, growth-dependent, AST methods are reliant on the growth rate of the bacteria and can take several days to several weeks to get results. A piezoelectric plate sensor can be used to measure an instant change in the minute physiological stresses of the bacteria cells when they are exposed to an effective concentration of antibiotic. This work aims to investigate the feasibility of piezoelectric plate sensors used for instantons AST (iAST) results and develop a road map for implementation of this technology into a clinical lab setting. Four Clinical and Laboratory Standards Institute (CLSI) quality control strains of bacteria were tested with a wide range of antibiotics from various drug classes using the piezoelectric sensor. Results were obtained within 30 minutes and compared to standard of care AST methods used in clinical labs, and CLSI prescribed ranges for each strain of bacteria. Aside from bacteria, mycobacteria and fungi were tested using the piezoelectric plate sensor to show this technology can be extended to categorizing various microorganisms. This thesis will also discuss a roadmap to fabricate more scalable sensors, and challenges associated with the different sensor designs. Date: Thursday, June 27, 2019 Time: 12:00 PM Place: HAMP G212

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Food in Kitchen area
by Son, Rosemary E 18 Jun '19

18 Jun '19

Hi All, There was a lunch and some food is left over. It is available to you on a first come first serve basis. Best, Rosemary

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Seminar Notice for Nelyan López Pérez's Ph.D. Final Exam. Seminar Monday, June 24, at 10:30 a.m., in ARMS 1028. Exam same day at 11:30 a.m., in ARMS 2237. “Detection of Early Stages of Degradation on PPTA Fibers Through the Use of Positron Annihilation L
by Son, Rosemary E 17 Jun '19

17 Jun '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR “Detection of Early Stages of Degradation on PPTA Fibers Through the Use of Positron Annihilation Lifetime Spectroscopy” By Nelyan López Pérez Purdue MSE Ph.D. Final Exam Advisor: Professor John A. Howarter ABSTRACT High-performance fibers used for ballistic protection are characterized by having outstanding mechanical properties such high modulus and strength. These mechanical properties are granted by the fiber’s chemical and physical structure as well as their high degree of orientation. Twaron fibers are one of the most commonly used fibers on soft body armors such as bulletproof vests. They are made from poly (p-phenylene terephthalamide) (PPTA), a rigid-rod and highly crystalline polymer. Although these fibers are crystalline and have great mechanical properties, their performance can decrease when they are exposed to different degradation factors. Free volume is the unoccupied space between the polymer molecules. It is responsible for characteristics such as diffusion and viscosity. Hence, the free volume changes as the polymer degrades. This thesis focuses on the effects of sonication, pH changes, and sweat on the free volume of PPTA fibers. A non-destructive technique known as positron annihilation lifetime spectroscopy (PALS) was used to measure the free volume in PPTA. Changes in the free volume of fibers degraded under different conditions were compared to their mechanical performance. Degradation in DI water, pH 4 and pH 10 aqueous solutions was conducted for 10 weeks at 80oC. Sweat degradation of PPTA fibers was also conducted for 10 weeks at 25oC, 50oC, and 100oC. Fibers degraded in pH4 and sweat solutions had greater loss of mechanical performance and changes in the free volume. PALS was able to detect changes in the nanostructure of PPTA fibers at early stages of degradation. This data was supported by mechanical tests and is complementary to other characterization techniques such as small angle X-ray scattering (SAXS). Results of this research are a stepping stone for future studies on lifetime predictions of bulletproof vests and the development of the next generation of soft body armors. Date: Monday, June 24, 2019 Time: 10:30 A.M. Place: ARMS 1028

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Seminar Reminder for Keyou Mao's Ph.D. Final Exam. Seminar Thursday, June 13, at 2:00 p.m., in ARMS 1028. Exam same day, at 3:00, in ARMS 2237. " Influence of Irradiation and Laser Welding on Deformation Mechanisms in Austenitic Steels
by Son, Rosemary E 12 Jun '19

12 Jun '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Influence of Irradiation and Laser Welding on Deformation Mechanisms in Austenitic Steels" By Keyou Mao Purdue MSE Ph.D. Final Exam Advisors: Professor Janelle P. Wharry and Professor Xinghang Zhang ABSTRACT This presentation will describe recent advancements in micro-mechanical testing that inform how deformation mechanisms in 304L stainless steels (SS) are affected by the presence of irradiation-induced defects. Austenitic 304L SS is one of the most widely utilized structural alloys in nuclear energy systems, but the role of irradiation on its underlying mechanisms of mechanical deformation remains relatively poorly understood. Now, recent advancement of micro-scale mechanical testing in a scanning electron microscope (SEM), coupled with site-specific transmission electron microscopy (TEM), enables us to precisely determine deformation mechanisms as a function of plastic strain and grain orientation. We focus on AISI 304L stainless steel irradiated in EBR-II to 20 displacements per atom (dpa) at 415°C, and contains ~3 atomic parts per million (appm) He amounting to 1.5% swelling. A portion of the specimen is laser welded in-hot cell; the laser weld heat affected zone (HAZ) is studied and considered to have undergone post-irradiation annealing (PIA). An archival, virgin specimen is also studied as a control. We conduct nanoindentation then prepare TEM lamellae from the indent plastic zone. TEM investigation reveals nucleation of deformation-induced α' martensite in the irradiated specimen, and metastable ε martensite in the PIA specimen. Meanwhile, the unirradiated control specimen exhibits evidence only of dislocation slip and twinning; this is unsurprising given that alternative deformation mechanisms such as twinning and martensitic transformation are typically observed only near cryogenic temperatures in austenitic SS. Surface area of irradiation-produced cavities contribute sufficient free energy to accommodate the martensitic transformation. The lower population of cavities in the PIA material enables ε martensite formation, while the higher cavity number density in the irradiated material causes α' martensite fromation. SEM-based micropillar compression tests confirm nanoindentation results. Irradiation damage could enable fundamental, mechanistic studies of deformation mechanisms that are typically only accessible at extremely low temperatures. Date: Thursday, June 13, 2019 Time: 2:00 P.M. Place: ARMS 1028

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Seminar Reminder for Li-Kai Lin's Ph.D. Final Exam. Seminar Thursday, June 13, at 10:00 a.m., in ARMS 1028. Exam, same day, at 11:00 a.m., in ARMS 2237. " Pollutant and Inflammation Marker Detection using Low-Cost and Portable Microfluidic Platform, an
by Son, Rosemary E 12 Jun '19

12 Jun '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Pollutant and Inflammation Marker Detection using Low-Cost and Portable Microfluidic Platform, and Flexible Microelectronic Platform" By Li-Kai Lin Purdue MSE Ph.D. Final Exam Advisor: Professor Lia Stanciu ABSTRACT Existing methods for pathogen/pollutant detection or wound infection monitoring employ high-cost instruments that could only be operated by trained personnel, and costly device-based detection requires a time-consuming field-to-lab process. This expensive process with multiple prerequisites prolongs the time that patients must wait for a diagnosis. Therefore, improved methods for point-of-care biosensing are necessary. In this study, we aimed to develop a direct, easy-to-use, portable, low cost, highly sensitive and selective sensor platform with the goal of pollutant detection and wound infection/cancer migration monitoring. This study has two main parts, including microfluidic, electrical, and optical sensing platforms. The first part focuses on Bisphenol A (BPA) lateral flow assay (LFA) detection; the second part focuses on the electrical sensing platform fabrication for one of the markers of inflammation, matrix metalloproteinases-9 (MMP-9), monitoring/detection. In the first part, we found that the few lateral flow assays (LFAs) established for detecting the endocrine-disrupting chemical BPA have employed citrate-stabilized gold nanoparticles (GNPs), which have inevitable limitations and instability issues. To address these limitations, a more stable and more sensitive biosensor is developed by designing strategies for modifying the surfaces of GNPs with polyethylene glycol and then testing their effectiveness and sensitivity toward BPA in an LFA. In addition, we describe the development of a new range-extended bisphenol A (BPA) detection method that uses a surface enhanced Raman scattering lateral flow assay (SERS-LFA) binary system. Furthermore, we examine advanced bisphenol A (BPA) lateral flow assays (LFAs) that use multiple nanosystems. The assays include three nanosystems, namely, gold nanostars, gold nanocubes, and gold nanorods, which are rarely applied in LFAs, compared with general gold nanoparticles. The developed LFAs show different performances in the detection of BPA. In the second part, a stable electrical sensing platform is developed for MMP-9 detection. Date: Thursday, June 13, 2019 Time: 10:00 A.M. Place: ARMS 1028

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Seminar Reminder for Cuncai Fan's Ph.D. Final Exam. Seminar June 12, at 9:00 a.m., in ARMS 1028. Exam June 12, at 10:00, in ARMS 2237. " Radiation Response of Nanostructured Cu"
by Son, Rosemary E 11 Jun '19

11 Jun '19

Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Radiation Response of Nanostructured Cu" By Cuncai Fan Purdue MSE Ph.D. Final Exam Advisor: Professor Xinghang Zhang ABSTRACT Irradiation of metals with energetic particles causes severe microstructural damage and degradation of mechanical properties. Prior studies on conventional polycrystalline materials have shown that the radiation tolerance of a material can often be enhanced by introducing a high density of interfaces that act as defect 'sinks' by attracting, absorbing and annihilating radiation induced defects. Nanostructured materials with a large volume fraction of interfaces, therefore, are assumed to be more radiation tolerant than conventional materials. This thesis focuses on understanding the fundamental mechanisms of radiation damage of nanostructured Cu fabricated by magnetron sputtering technique. High-density twin boundaries (TBs) and nanovoids (NVs) were successfully introduced into two distinct nanostructured Cu films with different orientations, including nanovoid-nanotwinned (NV-NT) Cu (111) and nanovoid (NV) Cu (110). The in-situ high-energy Kr ++ (1 MeV) and ex-situ low-energy (< 200 keV) He+ irradiations were subsequently preformed on the nanostructured Cu films. The in-situ TEM studies suggested that TBs and NVs are effective defect sinks that interact with defect clusters and impact their formation and distribution. Meanwhile, the preexisting nanostructures also undergo structural evolution under irradiation, in the form of void shrinkage and spheroidization, and twin boundary migration. In addition, the ex-situ micro-pillar compression tests revealed that the He-irradiated NV-NT Cu contains less defect clusters and maintain good work hardening ability. The underlying mechanisms of radiation-induced void shrinkage, twin boundary migration, and strengthening mechanisms are interpreted based on a combination of TEM analyses and molecular dynamics simulation, and phase-field modeling. This project provides important insight on the design of radiation tolerant nanostructured metals. Date: Wednesday, June 12, 2019 Time: 9:00 A.M. Place: ARMS 1028

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