Technology development for the production of biobased products from biorefinery carbohydrates—the US Department of Energy’s “Top 10” revisited

Thanks to its unusual stability, metallic gold has been used for thousands of years in jewelry, currency, chinaware, and so forth. However, gold had not become the chemists’ “precious metal” until very recently. In the past few years, reports on gold-catalyzed organic transformations have increased substantially. Thanks to gold-based catalysts, various organic transformations have been accessible under facile conditions with both high yields and chemoselectivity.

Gold-catalyzed organic transformations.

In this tutorial review, the fundamental concepts underlying the principles of green and sustainable chemistry - atom and step economy and the E factor - are presented, within the general context of efficiency in organic synthesis. The importance of waste minimisation through the widespread application of catalysis in all its forms – homogeneous, heterogeneous, organocatalysis and biocatalysis – is discussed. These general principles are illustrated with simple practical examples, such as alcohol oxidation and carbonylation and the asymmetric reduction of ketones. The latter reaction is exemplified by a three enzyme process for the production of a key intermediate in the synthesis of the cholesterol lowering agent, atorvastatin. The immobilisation of enzymes as cross-linked enzyme aggregates (CLEAs) as a means of optimizing operational performance is presented. The use of immobilised enzymes in catalytic cascade processes is illustrated with a trienzymatic process for the conversion of benzaldehyde to (S)-mandelic acid using a combi-CLEA containing three enzymes. Finally, the transition from fossil-based chemicals manufacture to a more sustainable biomass-based production is discussed.

http://www.industrialgreenchem.com/pdf-docs/abstracts/roger-sheldon.pdf

Fundamentals of green chemistry: efficiency in reaction design

This chapter is devoted to a more detailed examination of game theory. Game theory is an important tool for analyzing strategic behavior, is concerned with how individuals make decisions when they recognize that their actions affect, and are affected by, the actions of other individuals or groups. Strategic behavior recognizes that the decision-making process is frequently mutually interdependent. Game theory is the study of the strategic behavior involving the interaction of two or more individuals, teams, or firms, usually referred to as players. Two game theoretic scenarios were examined in this chapter: Simultaneous-move and multi-stage games. In simultaneous-move games the players effectively move at the same time. A normal-form game summarizes the players, possible strategies and payoffs from alternative strategies in a simultaneous-move game. Simultaneous-move games may be either noncooperative or cooperative. In contrast to noncooperative games, players of cooperative games engage in collusive behavior. A Nash equilibrium, which is a solution to a problem in game theory, occurs when the players’ payoffs cannot be improved by changing strategies. Simultaneous-move games may be either one-shot or repeated games. One-shot games are played only once. Repeated games are games that are played more than once. Infinitely-repeated games are played over and over again without end. Finitely-repeated games are played a limited number of times. Finitely-repeated games have certain or uncertain ends.

An Introduction to Game Theory

http://www.licn.phys.soton.ac.uk/restricted/Catalytic%20activity%20of%20Au%20nanoparticles-Lecture%201.pdf

Catalytic activity of Au nanoparticles

Bioethanol is produced by fermentation of biomass in increasing amounts to meet the growing demands for CO2neutral transportation fuels and to eventually remove the dependence on fossil fuels. However, bioethanol could also find use as a versatile, sustainable chemical feedstock. Herein, it is shown that it is possible to selectively oxidize ethanol into acetic acid in aqueous solution using air as the oxidant with a heterogeneous gold catalyst at temperatures of about 423 K and O2 pressures of 0.6 MPa. This reaction proceeds readily in aqueous acidic media and yields of up to 90% are achieved, with CO2 as the only major by-product. Thus, it constitutes a very simple, green route to acetic acid. The oxidation of ethanol by air into acetic acid over platinum was among the first heterogeneously catalyzed reactions to be reported. The initial discovery was made by D.bereiner about two centuries ago, even before the term catalysis was coined. So far, the reaction has not been used for large-scale production of acetic acid. Instead, three other routes to acetic acid have found industrial application: fermentation (vinegar), catalytic liquid-phase oxidation of butane, naphtha, or acetaldehyde, and the carbonylation of methanol, which has recently become the most important. In the most widely used industrial processes today, the feedstock is almost exclusively derived from fossil fuels. Thus, the production of acetic acid consumes fossil fuels and therefore contributes slightly to increasing CO2 levels in the atmosphere, and, more importantly, the cost of acetic acid is strongly dependent on the price of the fossil fuels. Therefore, it is interesting that the cost of renewable feedstocks has decreased dramatically relative to fossil fuel feedstocks over the last four decades. Specifically, the cost of corn relative to oil has decreased fivefold from 1950 to 2005. Today, bioethanol is mostly produced by fermentation of starchcontaining crops, such as corn or sugar cane, but it seems likely that cellulose-rich agricultural waste will gain importance as a feedstock in the future. Therefore, and also because of the continuing technological improvements of the production process, the cost of bioethanol is expected to decrease. Thus, with increasing fossil fuel prices, the production of acetic acid from bioethanol will become increasingly favorable compared to current fossil fuel-based methods. Clearly, this development requires that an active and selective catalyst for oxidation of ethanol with dioxygen to form acetic acid [Eq. (1)] is available.

Formation of Acetic Acid by Aqueous‐Phase Oxidation of Ethanol with Air in the Presence of a Heterogeneous Gold Catalyst

Duration Calculus is a real-time interval logic which can be used to specify and reason about timing and logical constraints on discrete states in a dynamic system It has been used to specify and verify designs for a number of real-time systems This paper extends the Duration Calculus with notations to capture properties of piecewise continuous states This is useful for reasoning about hybrid systems with a mixture of continuous and discrete states The proof theory of Duration Calculus is extended such that results proven using mathematical analysis can be used freely in the logic This provides a flexible interface to conventional control theory

An Extended Duration Calculus for Hybrid Real-Time Systems

The Duration Calculus (abbreviated DC) represents a logical approach for formal design of real-time systems, where real numbers are used to model time and Boolean valued functions over time are used to model states and events of real-time systems. Since its introduction, DC has been applied to many case studies and it has been extended in several directions. The aim of this paper is to provide a thorough presentation of the logic.

Duration calculus: Logical foundations

Decidability and Undecidability Results for Duration Calculus

As computers increasingly control the systems and services we depend upon within our daily lives like transport, communications, and the media, ensuring these systems function correctly is of utmost importance. This book consists of twelve chapters and one historical account that were presented at a workshop in London in 2015, marking the 25th anniversary of the European ESPRIT Basic Research project ProCoS (Provably Correct Systems). The ProCoS I and II projects pioneered and accelerated the automation of verification techniques, resulting in a wide range of applications within many trades and sectors such as aerospace, electronics, communications, and retail. The following topics are covered: An historical account of the ProCoS projectHybrid Systems Correctness of Concurrent Algorithms Interfaces and Linking Automatic VerificationRun-time Assertions Checking Formal and Semi-Formal Methods Provably Correct Systems provides researchers, designers and engineers with a complete overview of the ProCoS initiative, past and present, and explores current developments and perspectives within the field.

/pdf/provably-correct-systems-4wcmhrt2ms.pdf

Michael R. Hansen

Papers

Formation of Acetic Acid by Aqueous‐Phase Oxidation of Ethanol with Air in the Presence of a Heterogeneous Gold Catalyst

An Extended Duration Calculus for Hybrid Real-Time Systems

Duration calculus: Logical foundations

Decidability and Undecidability Results for Duration Calculus

Provably Correct Systems