Tribute to Bessie, The Jalopy

Bessie was a good old Ford, even if she was of the 1924 vintage, with old-fashioned clincker tires and all the out-of-date accessories that made her comfortable like an old, old shoe

Social Cash Transfers in Zambia: What Is Their Impact?

Social cash transfers (SCTs) have become increasingly popular in Sub-Saharan Africa, because growth-centred development policies have failed to reduce poverty. SCTs support the consumption of the poorest, and allow them to invest in human and other forms of capital that reduce the intergenerational transmission of poverty. (...)Social Cash Transfers in Zambia: What Is Their Impact?

Synthesis of an Epoxide for TMM Cycloadditions

In order to produce a highly functionalized five-membered ring useful for further synthetic processes via Palladium catalysis, a series of precursors need to be synthesized in order to form the epoxide used in cyclic formation. First, a trimethylsilane alcohol is synthesized from beta-Methallyl alcohol. The alcohol will then be subjected to Swern oxidation conditions, forming a TMS aldehyde. The aldehyde prepared will then undergo epoxidation, forming the desired precursor for Palladium catalyzed cycloaddition. The Swern oxidation has yet to occur in good conversion due to sensitivity, but when performed using a model compound the oxidation, and epoxidation both worked to form a model epoxide precursor

Preparation of an Epoxide Precursor for Palladium-Catalyzed Trimethylenemethane Cycloaddition

In order to produce a highly functionalized five-membered ring useful for further synthetic processes via palladium catalysis, a series of precursors need to be synthesized in order to form the epoxide used in cyclic formation. First, a trimethylsilane alcohol is synthesized from beta-methallyl alcohol. The alcohol will then be subjected to Swern oxidation conditions, forming a TMS aldehyde. The aldehyde prepared will then undergo epoxidation, forming the desired precursor for Palladium catalyzed cycloaddition. These reactions occur in good conversion, and a good amount of epoxide is being amassed for use in the palladium-catalyzed cycloaddition research

A survey of fractured SrTiO3_3 surfaces: from the micro-meter to nano-meter scale

Cross-sectional scanning tunneling microscopy was utilized to study fractured perovskie oxide surfaces. It was found for the non-cleavable perovskite oxide, SrTiO$_{3}$, that atomically flat terraces could be routinely created with a controlled fracturing procedure. Optical and scanning electron microscopy as well as a profilometer were used to obtain the information from sub-millimeter to sub-micrometer scales of the fractured surface topography.Comment: 9 pages, 4 figure

Lightweight composite reflector panels

The Hexel Corp. has produced additional composite panels, based on JPL designs, that: (1) have increased the panel size from 0.15 to 0.40 meters, (2) have improved the as-manufactured surface precision 3.0 to approx. 1.0 micron RMS, (3) have utilized different numbers of face sheet plys, (4) have improved face sheet fiber orientation, (5) have variations of aluminum honeycomb core cell size, (6) have combined graphite/epoxy (Gr/Ep) face sheets with E-glass honeycomb cores, and (7) have used standard aluminum core with face sheets composed of combinations of glass, Kevlar, and carbon fibers. Additionally, JPL has identified candidate alternate materials for the facesheets and core, modified the baseline polymer panel matrix material, and developed new concepts for panel composite cores. Dornier designed and fabricated three 0.6 meter Gr/Ep panels, that were evaluated by JPL. Results of both the Hexel and Dornier panel work were used to characterize the state-of-the-art for Gr/Ep mirrors

High-efficiency generation of nanomaterials via laser ablation synthesis in solution with in-situ diagnostics for closed-loop control

Driven by an ever-increasing demand for nanomaterials with specific functionalities, physical synthesis techniques such as Laser Ablation Synthesis in Solution (LASiS) have gained significant interest over in recent years. Commercial wet chemical synthesis methods, while having significantly higher nanomaterial yields than LASiS, typically have considerable negative environmental impact through the use of harmful reagents and solvents. LASiS therefore represents a route towards the sustainable “green” production of nanomaterials however the significant challenge to its commercialization is that of comparably low nanomaterial yields. Significant effort has been made towards increasing the production rates of LASiS, however many of the reported advances have relied on the use of high power (>20 W) or short pulse (<10 ps) laser systems which have high capital costs. Other advances have examined moving from batch production in small volumes towards the use of continuous production through the use of solvent flow systems. Combining these advances, we have developed a new system for nanomaterial generation via LASiS incorporating a low cost, low power (< 4W) Nd:YAG laser and solvent flow system for high-efficiency nanomaterial generation. This study has shown an increase in productivity from 2.5± 0.5 mg/hr for an 11 mL batch colloid, to continuous production yields of 17± 0.7 mg/hr under flow conditions