Silicon carbide equipments for process intensification of silicon reactions.

Bluestar Silicones, one of the worldwide leaders in silicones chemistry, proposes a R&D project, aiming to design new equipment for the transposition of batch to continuous processes. The safety and environmental issues linked to this type of chemicals, and the productivity targets as well require innovative technologies characterized by a fair corrosion resistance and high heat and mass transfer performances. A preliminary prototype of heat exchanger reactor made of silicon carbide plates has been developed by the LGC in collaboration with a SME specialist of SiC, Boostec. It has allowed the pilot feasibility with some reactions of industrial interest for a Bluestar Silicones to be highlighted. Now, it is necessary to pursue this effort and beyond the feasibility step to go on up to the design of an industrial reactor. This project corresponds to a programme of innovative process development in order to design cleaner, safer and less consuming devices

Reply to the correspondence: "On the fracture toughness of bioinspired ceramic materials"

This is a reply to the correspondence of Prof. Robert Ritchie: "On the fracture toughness of bioinspired ceramic materials", submitted to Nature Materials, which discusses the fracture toughness values of the following papers: Bouville, F., Maire, E., Meille, S., Van de Moort\`ele, B., Stevenson, A. J., & Deville, S. (2014). Strong, tough and stiff bioinspired ceramics from brittle constituents. Nature Materials, 13(5), 508-514 and Le Ferrand, H., Bouville, F., Niebel, T. P., & Studart, A. R. (2015). Magnetically assisted slip casting of bioinspired heterogeneous composites. Nature Materials, 14(11), 1172-1172.Comment: 5 pages, 2 figure

Three Essays in Applied Health Economics

The US healthcare system faces numerous challenges. In this dissertation I study issues of access to care, healthcare costs, and responses to the opioid epidemic. I take an applied economic approach, using causal inference methods to examine the effects of recent policies and changes to landscape of healthcare providers. In the first chapter, I study urgent care centers (UCCs), which provide timely care for nonchronic, low-severity health conditions. Over the past decade, UCCs have disrupted the market for outpatient healthcare. The entry of these new providers may reduce healthcare spending by diverting care from higher cost emergency departments. Alternatively, if UCC entry increases healthcare utilization, total spending may increase. I use administrative insurance claims data from Massachusetts to estimate the effect of UCC entry on healthcare utilization and spending. The data span 2012 to 2015, during which the number of UCCs increased by 88 percent. In the months immediately following UCC entry, patients substitute away from other outpatient providers. Patients substantially reduce visits to physician offices and outpatient clinics, and slightly reduce visits to emergency departments. Overall, UCC entry increases the efficiency of the healthcare system. Aggregate spending appears to modestly decline, while in areas with few primary care providers, UCC entry increases the total number of healthcare visits. The second chapter examines the effect of insurance coverage on utilization of prescription drugs that treat ADHD. It uses a regression discontinuity design that exploits the change in eligibility for dependent insurance coverage at age 26. From 2014-2017, the probability of insurance coverage decreased by 5 percentage points at this threshold. I examine the effect on central nervous system stimulant expenditures using an administrative database that captures all prescriptions filled at Kentucky pharmacies. At the eligibility threshold, the probability of purchasing a prescription drops by 5-7 percentage points and expenditures fall by 18-27 percent. Only 30 percent of the decrease in prescriptions purchased with insurance is offset by an increase in prescriptions purchased out-of-pocket. People also decrease expenditures by switching from branded medications to a category of similar generics that costs $104 (43 percent) less per prescription. The probability of filling a prescription recovers as people regain insurance, but decreases in expenditures persist longer-term. The third chapter studies opioid control policies that target the prescribing behavior of health care providers. In this chapter, (co-authored by Thomas Buchmueller and Colleen Carey), we study the first comprehensive state-level policy requiring providers to access patients' opioid history before making prescribing decisions. We compare prescribers in Kentucky, which implemented this policy in 2012, to those in a control state, Indiana. Our main difference-in-differences analysis uses the universe of prescriptions filled in the two states to assess how the information provided affected prescribing behavior. We find that a significant share of low-volume providers stopped prescribing opioids altogether after the policy was implemented, though this change accounted for a small share of the reduction in total volume. The most important margin of response was to prescribe opioids to fewer patients. While providers disproportionately discontinued treating patients whose opioid histories showed the use of multiple providers, there were also economically-meaningful reductions for patients without multiple providers and single-use acute patients.PHDBusiness AdministrationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/169855/1/gmeille_1.pd

Microstructures et propriétés mécaniques de céramiques poreuses

Les céramiques à forte porosité (supérieure à 30 vol%) sont utilisées dans une très large gamme d'applications industrielles : matériaux de construction, membranes de filtration, substituts osseux, matériaux pour la production d'énergie... Leur comportement mécanique, et notamment à la rupture, est souvent peu connu en comparaison aux céramiques denses d'une part et aux matériaux poreux à base de polymère ou de métal d'autre part. Ces matériaux doivent cependant supporter des sollicitations mécaniques complexes en usage

Insights into the formation of chiral second sphere coordination complexes with aromatic tris amines: combined single crystal X-ray crystallography and molecular modeling analyses

Control over the formation of non-centrosymmetric chiral materials is highly desirable due to their potential applications in areas such as ferroelectricity, piezo- and pyroelectricity, and second harmonic generation.[1] Unfortunately, the development of a reliable approach to induce the formation of a chiral material from achiral molecules remains a great challenge in the field of molecular chemistry.[2] Furthermore, the understanding of the driving forces behind those aggregations is a prerequisite for the design and construction of chiral molecular arrays. C3-symmetrical tripodal molecules have emerged as attractive organic frameworks for the construction of chiral coordination compounds.[3] In the present contribution we report about a family of isostructural, chiral supramolecular networks obtained in the solid state by exploiting second sphere coordination interactions in the self-assembly of achiral tris amines L1 and L2 with tetrahalometallate and halide ions. Quantum-Mechanical calculations (including the usage of approaches specific for crystalline solid phases) provided important insights into the intramolecular and packing interactions which determine chirality, pointing to a direct effect of the methyl groups of the central benzene ring of the tris amines. [4] References [1] (a) P. A. Maggard, C. L. Stern and K. R. Poeppelmeier, J. Am. Chem. Soc., 2001, 123, 7742–7743; (b) M. Liu, L. Zhang and T. Wang, Chem. Rev., 2015, DOI: 10.1021/ Q5 cr500671p. [2] P. S. Halasyamani and K. R. Poeppelmeyer, Chem. Mater., 1998, 10, 2753–2769. [3] Z. Dai and J. W. Canary, New J. Chem., 2007, 31, 1708–1718. [4] H. Yu, L. Li, J. Gao, J. Tong, W. Zheng, M. Cametti, A. Famulari, S.V. Meille, F. Guo and J. Martí-Rujas Journal Article Dalton Trans., 2015,44, 15960-15965. DOI: 10.1039/C5DT02387D, Pape