The Café will resume on May 8th
Poor understanding of heat transfer across solid-liquid interfaces bottlenecks the development of nanocomposite materials for applications in thermal interface materials, energy generation, catalysis, and thermotherapeutics. Thermal engineers have identified the main parameters governing interfacial heat transfer; however, the interplay among these parameters is rather complex. This talk calls for anybody interested in the topic to develop a proper understanding of interfaces before addressing the problem of heat transfer across interfaces.
Punishment, or the threat of punishment, is a critical component for the establishment and maintenance of social system governed by norms. We would like to create robots that obey social norms. Do we then need a means for punishing our robots and, if so, how do punish a robot? This talk examines these and related questions.
Every year the world produces more trash and demands more energy. While the integrated biorefinery could produce renewable fuels from waste, its economic viability hinges on the ability to upgrade the unstable bio-oils currently produced, and to develop high-value byproducts. In a new approach to the integrated biorefinery, we incorporate inorganic compounds into cellulosic feedstocks to engineer solid products such as nanomaterials via biotemplating, heterogeneous adsorbents, and tunable carbon electrode materials, while simultaneously upgrading biofuels. This reduces the need for downstream upgrading and improves the economic viability of sustainable biomass to renewable fuel conversions.
Supramolecular chemistry is a strategy to engineer materials through directional noncovalent interactions (e.g., hydrogen bonds, host-guest interactions, metal coordination). Despite the dynamic and reversible nature of supramolecular interactions, their full integration into synthetic materials design platforms is sluggish. Nature, however, fabricates some of the most beautiful 1D, 2D, and 3D self-assembled architectures using a combined array of complex synthetic techniques and exploitation of noncovalent chemistry. So the question arises… why can’t we do the same to control molecular architecture?
The emergence of antibiotic resistance driven in part by the overuse of broad-spectrum antibiotics represents a growing health crisis worldwide. This challenge is exacerbated by reduced financial incentives and regulatory challenges in the drug development pipeline. We are developing a precision antimicrobial initiative enabled by recent advancements in life science, material science, and data science to stay ahead on the drug resistance treadmill.
Large birds (such as hawks, vultures, and eagles) as well as human sailplane pilots routinely exploit vertical air motion (lift) to remain aloft for several hours and fly hundreds of miles without flapping wings or the use of engines. We are developing algorithms inspired by both human- and bird-soaring to improve the flight of drones: we teach to soar. This talk will discuss what we have learned about robotic and bird flight, covering planning and flight control of robotic aircraft as well as our observations of bird flight.
Designing and building self-propelled particles (artificial microswimmers) with the capabilities of complex swimming (combined translational and rotational motion) is challenging with conventional fabrication techniques, such as lithography or electrochemical deposition. In this talk, I will present on an alternative fabrication technique, 2-photon lithography, that has enabled 3-D printing of microswimmers capable of complex swimming behavior. This research demonstrates the advantages of the 2-photon lithography for 3-D printing and rapidly optimizing microstructures.
Multifunctional materials can act as machines for sensing, actuation, morphing, damage mitigation and limiting detrimental structural loads. Industrial applications range from biomedical, aerospace, civil and automotive. Shape memory alloys are a class of multifunctional materials that undergo large shape changes, and upon heating or removing external stimuli “remember” their original shape and form. Underlying solid-state atomic and microstructure length scale phase transitions are reversible, which begets the bulk scale memory and thus smartly designing the microstructure can tailor alloy behavior. In this talk, I will discuss our work using macro and micro-scale additive manufacturing and efforts to establish the interrelationships between novel fabrication technologies and shape memory functionality.
For centuries, universities have contributed meaningfully to society through innovation, discovery, and educating future generations. In universities around the world, students and faculty are utilizing their intellectual resources and human capacity to tackle global challenges such as poverty, hunger, health, equality, and climate change. Unfortunately, sometimes in the pursuit to help others, we forget to reflect on the ethical issues that our actions may cause during and after international engagement. Come talk with me about ethical challenges in university-community international development and discuss how we can shift perceptions among university stakeholders from thinking of university international development as philanthropic to one of mutual respect and reciprocity.
The “breathing”, or the vibrational motion of materials, contains rich information about the physical and chemical properties and states. Raman spectroscopy is a powerful analytical tool to see such “breathing”. In this talk, I will present some examples on how we can “see breathing” of 2D materials systems, including twisted bilayer MoS2 and few-layer black phosphorus, and how the “breathing” behaviors of coupled nanomaterials are influenced by each other which leads to new opportunities in chemical and biological sensing.
Animals move with remarkable agility and robustness, which is unparalleled by current physical (robot) systems. Major conceptual breakthroughs are needed to synthesize an engineering ‘blueprint’ of animal locomotion. Emphasizing the senses of touch and vision, I will draw on control tasks in running and flying insects to describe how animals implement feedback control. Throughout I will highlight opportunities for multidisciplinary collaborations at the intersection of material science, biomechanics, neurogenetics, mathematics and robotics.
A traditional science classroom spends the first few weeks teaching students how scientists do their work and the rest of the class telling them what scientists already know. Current reforms in STEM education promote engaging students in the practices of researchers to make sense of disciplinary content. Since most K-12 teachers have little experience in research, this creates a serious challenge. However, teacher professional development workshops based on authentic research projects can build teachers capacity to teach in this way, and can serve as effective broader impacts programs for federally funded research grants.
The molecules of life, proteins and nucleic acids are essential parts of every living organism and participate in most processes within cells. Many proteins and some RNA are enzymes that catalyze a number of biochemical reactions. These macromolecules purified from different research labs across Penn State have been studied using a variety of biophysical techniques in our facility. The methods we employ include X-ray crystallography, solution small angle X-ray scattering (SAXS), dynamic light scattering, bio-layer interferometry, circular dichroism spectroscopy, micro electron diffraction, molecular modeling, isothermal calorimetry and differential scanning calorimetry. Come learn about some recent examples where the facility has assisted researchers in delineating the structure-function enigmas of various macromolecules.
I will discuss our efforts in investigating molecular orientation at substrate and organic interfaces for the production of artificial “nanograss”. We developed a method for growing oriented single-crystal nanopillars at graphene interfaces for use in high performance organic solar cells. The use of organic single-crystalline devices will have a major impact in accelerating the emerging area of organic electronics, as these highly ordered systems will enable one to extract intrinsic charge carrier transport phenomena that cannot be accurately determined from disordered systems common to amorphous and/or polycrystalline films used in mainstream devices.
We will return on Tuesday, March 13, 2018.
We communicate in different ways: hand-shaking, texting, speaking, etc. We speak using different languages: English, Chinese, Spanish, etc., and many of us are bilingual or even multilingual. Living cells also communicate with others in their multicellular society. But are cells monolingual or multilingual? It has been long believed that cells only speak a biochemical language, wherein cells communicate through message-passing factors called morphogens. In this talk I will show compelling evidence that living cells also communicate in the language of mechanics. This bilingual cell communication leads to various fundamental biological functions in development and repair, and dysfunctions in disease and injury. To better understand these phenomena requires multidisciplinary collaborations among mechanicians, chemists, materials scientists, and biologists.
When molecules are confined in nanopores (0.5-10 nm), their characteristics can be altered significantly. For example: certain molecules can be easily converted into other molecules only if they are trapped in a confined space, which inspired catalytic production of gasoline and diesel in petroleum refining. Our research group studies two types of nanoporous materials: zeolites and metal-organic frameworks (MOFs), and how material morphology can affect their performance. I will demonstrate how zeolites and MOFs can be used in energy-related gas separations and catalytic production of fuels from natural gas derivatives. I will also mention their potential future applications in biological and medical sciences.