Oxalates as Activating Groups for Alcohols in Visible Light Photoredox Catalysis: Formation of Quaternary Centers by Redox-Neutral Fragment Coupling.

Alkyl oxalates are new bench-stable alcohol-activating groups for radical generation under visible light photoredox conditions. Using these precursors, the first net redox-neutral coupling of tertiary and secondary alcohols with electron-deficient alkenes is achieved

End-to-end continuous flow synthesis and purification of diphenhydramine hydrochloride featuring atom economy, in-line separation, and flow of molten ammonium salts

A continuous end-to-end synthesis and purification of diphenhydramine hydrochloride featuring atom economy and waste minimization is described. Combining a 1 : 1 molar ratio of the two starting material streams (chlorodiphenylmethane and N,N-dimethylaminoethanol) in the absence of additional solvent at high temperature gives the target compound directly as a molten salt (ionic liquid above 168 °C) in high yield. This represents the first example of continuous active pharmaceutical ingredient (API) production in this manner. Six of the twelve principles of green chemistry as defined by the American Chemical Society are achieved, most prominently waste minimization and atom economy.United States. Defense Advanced Research Projects Agency (DARPA N66001-11-C-4147

The time resolved measurement of ultrashort THz-band electric fields without an ultrashort probe

The time-resolved detection of ultrashort pulsed THz-band electric field temporal profiles without an ultrashort laser probe is demonstrated. A non-linear interaction between a narrow-bandwidth optical probe and the THz pulse transposes the THz spectral intensity and phase information to the optical region, thereby generating an optical pulse whose temporal electric field envelope replicates the temporal profile of the real THz electric field. This optical envelope is characterised via an autocorrelation based FROG measurement, hence revealing the THz temporal profile. The combination of a narrow-bandwidth, long duration, optical probe and self-referenced FROG makes the technique inherently immune to timing jitter between the optical probe and THz pulse, and may find particular application where the THz field is not initially generated via ultrashort laser methods, such as the measurement of longitudinal electron bunch profiles in particle accelerators.Comment: 7 pages, 3 figures, submitted to AP

Development of space-syaple thermal-control coatings triannual report, jan. 20 - may 20, 1965

Development of stable thermal control coatings with low solar absorptance to infrared emittance rati

The influence of soil textural stratification and compaction on moisture flow

This bulletin reports on Department of Soils research project 211, Infiltration. This study was performed in cooperation with the Soil and Water Conservation Research Division, ARS, U.S. Department of Agriculture--P. [3].Digitized 2007 AES.Includes bibliographical references (page 14)

Convergence science in the Anthropocene: Navigating the known and unknown

Rapidly changing ecological and social systems currently pose significant societal challenges. Navigating the complexity of social-ecological change requires ap- proaches able to cope with, and potentially solve, both foreseen and unforeseen societal challenges. The emergent field of convergence addresses the intricacies of such challenges, and is thus relevant to a broad range of interdisciplinary issues. This paper suggests a way to conceptualize convergence research. It discusses how it relates to two major societal challenges (adaptation, transformation), and to the generation of policy-relevant science. It also points out limitations to the further development of convergence research

The Finite Field Kakeya Problem

A Besicovitch set in AG(n,q) is a set of points containing a line in every direction. The Kakeya problem is to determine the minimal size of such a set. We solve the Kakeya problem in the plane, and substantially improve the known bounds for n greater than 4.Comment: 13 page

Costly Offers and the Equilibration Properties of the Multiple Unit Double Auction Under Conditions of Unpredictable Shifts of Demand and Supply

The paper reports on the behavior of markets in which a transactions cost is imposed in the form of a tax on bids and asks that are tendered in the market. That is, in the markets studied communication with the other side of the market was costly. The markets were nonstationary in the sense that market demand and market supply shifted unpredictably each period and the markets were organized by the computerized Multiple Unit Double Auction. The results are as follow. (1) A market equilibration process is observed across the periods of nonstationary markets. (2) The imposition of the cost on offers did not negate the tendency toward market equilibration but the price discovery process was "incomplete" relative to the free offer case. (3) Price equilibration with the offer cost was slower and efficiencies were reduced