Synthesis, Molecular Structure and Dynamic Behaviour of the Chiral Cluster (u*H)4Ru4(CO)9(HC(PPh2)3)

The synthesis and study of the dynamic behaviour of (u*H)4Ru4(CO)9(HC(PPh2)3) are described. The X-ray structural determination shows this cluster to be chiral, the asymmetry arising from a helical array of phenyl groups on the tripod ligand

Hydrogen Separation Membranes Annual Report for FY 2006.

The objective of this work is to develop dense ceramic membranes for separating hydrogen from other gaseous components in a nongalvanic mode, i.e., without using an external power supply or electrical circuitry. This goal of this project is to develop two types of dense ceramic membrane for producing hydrogen nongalvanically, i.e., without electrodes or external power supply, at commercially significant fluxes under industrially relevant operating conditions. The first type of membrane, hydrogen transport membranes (HTMs), will be used to separate hydrogen from gas mixtures such as the product streams from coal gasification, methane partial oxidation, and water-gas shift reactions. Potential ancillary uses of HTMs include dehydrogenation and olefin production, as well as hydrogen recovery in petroleum refineries and ammonia synthesis plants, the largest current users of deliberately produced hydrogen. The second type of membrane, oxygen transport membranes (OTMs), will produce hydrogen by nongalvanically removing oxygen that is generated when water dissociates at elevated temperatures. This report describes progress that was made during FY 2006 on the development of OTM and HTM materials

The Pitfalls of Central Clearing in the Presence of Systematic Risk

Through the lens of market participants' objective to minimize counterparty risk, we provide an explanation for the reluctance to clear derivative trades in the absence of a central clearing obligation. We develop a comprehensive understanding of the benefits and potential pitfalls with respect to a single market participant's counterparty risk exposure when moving from a bilateral to a clearing architecture for derivative markets. Previous studies suggest that central clearing is beneficial for single market participants in the presence of a sufficiently large number of clearing members. We show that three elements can render central clearing harmful for a market participant's counterparty risk exposure regardless of the number of its counterparties: 1) correlation across and within derivative classes (i.e., systematic risk), 2) collateralization of derivative claims, and 3) loss sharing among clearing members. Our results have substantial implications for the design of derivatives markets, and highlight that recent central clearing reforms might not incentivize market participants to clear derivatives

Social Safety Nets for Food and Nutritional Security in India

This paper brings together existing literature on the Mahatma Gandhi National Rural Employment Guarantee Act (MGNRGEA) and the Public Distribution System (PDS) in India, offering a narrative review of the evidence on impacts on food security, health and nutrition of beneficiaries. Both programs operate on a large scale and have the capacity to impact the factors leading to undernutrition. It is evident that despite the deficiencies in implementation, both the MGNREGA and the PDS are inclusive and reach the poor and the marginalized who are likely to also experience greater undernutrition and poor health. Data challenges have however prevented researchers from conducting studies that assess the ultimate impact of these two large-scale programs on health and nutrition. The evidence that exists suggests largely positive impacts indicating a clear potential to make these programs more nutrition sensitive not just by incorporating elements that would explicitly address nutritional concerns but also by directing specific attention to innovations that strengthen critical complementarities and synergies that exist between the two programs

Fixed bed testing of durable, steam resistant zinc oxide containing sorbents

The US Department of Energy is currently developing Integrated Gasification combined Cycle (IGCC) systems for electrical power generation. It has been predicted that IGCC plants with hot gas cleanup will be superior to conventional pulverized coal-fired power plants in overall plant efficiency and environmental performance. Development of a suitable regenerable sorbent is a major barrier issue in the hot gas cleanup program for IGCC systems. This has been a challenging problem during the last 20 years, since many of the sorbents developed in the program could not retain their reactivity and physical integrity during repeated cycles of sulfidation and regeneration reactions. Two promising sorbents and (METC6), which were capable of sustaining their reactivity and physical integrity during repeated sulfidation/regeneration cycles, have been developed at the Morgantown Energy Technology Center (METC) during the past year. These sorbents were tested (sulfided) both in low-pressure (260 kPa/37.7 psia) and high-pressure (1034 kPa/150 psia) fixed-bed reactors at 538{degrees}C (1000{degrees}F) with simulated KRW coal gas. High-pressure testing was continued for 20 cycles with steam regeneration. There were no appreciable changes in sulfidation capacity of the sorbents during the 20-cycle testing. The crush strength of the sorbent actually improved after 20 cycles and there were no indications of spalling or any other physical deterioration of the sorbents. In testing to date, these sorbents exhibit better overall sulfur capture performance than the conventional sorbents

Organometallic derivatives of diphosphinoamines, X2PN(R)PX2X_2PN(R)PX_2. Reactions with carbonyl derivatives of group 6 metals and iron pentacarbonyl. The crystal structures of [Mo(CO)4PhN(P(Oph)2)2][Mo(CO)_4PhN(P(Oph)_2)_2] and [W(CO)_4\hspace{1mm}^iPrN(PPh_2)_2]

The diphosphinoamines $X_2PN(R)PX_2 (L) (R = Me or Ph, X = OCH_2CF_3$or OPh; $R = Ph, X = OC_6H_4Br-p; R = ^iPr, X = Ph)$ react with group 6 metal carbonyl derivatives to yield the cis-chelate complexes [M(CO)4(L-PP′)]. The structures of cis-$[Mo(CO)_4PhN(P(OPh)_2)_2]$(3d) and cis-[W(CO)_4\hspace{1mm}^iPrN(PPh_2)_2] (4f) have been established by single crystal X-ray diffraction studies. Reactions with iron pentacarbonyl yield complexes in which a chelating or a bridged-bidentate mode of coordination of the ligands is observed

Organometallic derivatives of diphosphinoamines, X<SUB>2</SUB>PN(R)PX<SUB>2</SUB>. Reactions with carbonyl derivatives of group 6 metals and iron pentacarbonyl. The crystal structures of [Mo(CO)<SUB>4</SUB>PhN(P(OPh)<SUB>2</SUB>)<SUB>2</SUB>] and [W(CO)<SUB>4</SUB><SUP>i</SUP>PrN(PPh<SUB>2</SUB>)<SUB>2</SUB>]

The diphosphinoamines X2PN(R)PX2 (L) (R = Me or Ph, X = OCH2CF3 or OPh; R = Ph, X = OC6H4Br-p; R = iPr, X = Ph) react with group 6 metal carbonyl derivatives to yield the cis-chelate complexes [M(CO)4(L-PP')]. The structures of cis-[Mo(CO)4PhN(P(OPh)2)2] (3d) and cis-[W(CO)4iPrN(PPh2)2] (4f) have been established by single crystal X-ray diffraction studies. Reactions with iron pentacarbonyl yield complexes in which a chelating or a bridged-bidentate mode of coordination of the ligands is observed