Gold/Iron Carbonyl Clusters for Tailored Au/FeOx Supported Catalysts

A novel preparation method was developed for the preparation of gold/iron oxide supported catalysts using the bimetallic carbonyl cluster salts [NEt4]4[Au4Fe4(CO)16] and [NEt4][AuFe4(CO)16] as precursors of highly dispersed nanoparticles over different supports. A series of catalysts with different metal loadings were prepared and tested in the complete oxidation of dichlorobenzene, toluene, methanol and in the preferential oxidation of CO in the presence of H2 (PROX) as model reactions. The characterization by BET, XRD, TEM, H2-TPR, ICP-AES and XPS point out the way the nature of the precursors and the thermal treatment conditions affected the dispersion of the active phase and their catalytic activity in the studied reactions

The Differential Sentencing of White-Collar Offenders in Ten Federal District Courts

While sociologist have long debated the relationship between the status characteristics of criminal offenders and the sentences they receive, they have done so with data sets drawn from state courts whose prosecutorial resources are focused almost entirely on low status defendants. Qualitative and quantitative data analyzed in this paper are drawn from ten federal district courts whose statutes and resources provide greater potential for the prosecution of the white-collar crimes of higher status offenders. Three questions are addressed: (1) Are there substantial jurisdictional differences in the prosecution of white-collar cases? if so, (2) Are there corresponding jurisdictional differences in the sentencing of white-collar cases? and (3) Within jurisdictions, are there further differences in the factors that influence sentencing decisions in white-collar as compared to other kinds of cases? The data are analyzed from a perspective that emphasizes organizational considerations: we conceptualize the criminal justice process as a loosely coupled system and the use of prosecutorial resources as proactive and reactive. We argue that the expanded prosecution of white-collar persons for their white-collar crimes requires a proactive prosecutorial policy and a tightening of the coupling between plea negotiations and sentencing decisions in the prosecutorial and judicial subsystems. Our quantitative analysis reveals that one district follows a uniquely proactive pattern. As expected, this proactive district also exhibits a unique leniency in the sentencing of college educated white-collar criminals that is related to earlier plea and charging decisions. A rather different and unanticipated pattern of leniency is found in this district for less educated white-collar offenders. A conclusion of this study is that there may be an inverse relationship between the volume of white-collar prosecutions and the severity with which they are sentenced

Synthesis of Nanometric Oxide Powders for SOFC Applications

Fuel Cell are electrochemical devices that convert the chemical energy of a fuel (generally hydrogen) and oxygen in electrical energy producing at the same time water and heat. These systems are interesting not only for the possibility of producing "clean" energy but also for the benefit linked to the high conversion efficiency. The Solid Oxide Fuel Cells (SOFC) in particular, are considered the most promising among the new systems of energy production especially for their intrinsic fuel flexibility (hydrocarbon, hydrogen, biogas, etc.). For these reasons, basic as well as technological studies focused on the improvement of the materials and production paths are of paramount importance to obtain SOFC competitive with the traditional energy production systems. Part of ISTEC research is devoted to the development of chemical synthesis able to produce tailored nano-oxides with characteristics suitable for SOFC applications. In particular soft-chemical synthesis routs were optimized to synthesize ceria and gadolinium-doped ceria nano-powders. Nano-structured powders exhibit in fact several size-dependant properties; among those, their high reactivity allows milder sintering conditions and as a consequence, better performances and lower production costs. Cerium oxide has been extensively used in a wide range of applications ranging from three way catalysts to gas sensors. When doped with gadolinum oxide, ceria becomes an alternative electrolyte for Intermediate Temperature Solid Oxide Fuel Cells (IT-SOFC). Nano-structured ceria has recently attracted extensive attention because of its properties which were found to be size, shape and orientation-dependent. Although several methods were proposed for the synthesis of ultrafine powders, most of them generally require a subsequent calcination step. This thermal treatment is known to promote the crystallisation of the amorphous phase; however it also induces aggregation, reducing the specific surface area of the powder. The aim of this work was to produce ultrafine, pure and Gd-doped CeO2 powders using standard chemical routes coupled with non-conventional heating processes. Nano-crystalline ceria and Ce1-xGdxO2- (GDC) particles were successfully produced under mild conditions with two different methods: i) applying infrared heating to a common sol-gel process (IR-SG); ii) assisting with microwaves a polyol precipitation method (MW-PP). The correlation of the synthesis parameters with the thermodynamic and kinetic factors involved, allowed the control of fundamental properties such as size distribution, purity and morphology. Nano-structured ceria of particle size in the micron range with complex morphology and high specific surface area was prepared by adjusting the MW-PP synthesis conditions (temperature, time and templating agents). These mesoporous aggregates were found to be active in the catalytic oxidation of toluene. Moreover the GDC obtained through the optimization of the IR-SG parameters exhibited values of ionic conductivity higher than the ones showed by commercial and conventional sol-gel produced powders of similar compositio

Microwave-assisted synthesis of cerium oxide nanoparticles

Cerium oxide has recently received a lot of attention as a consequence of its catalytic properties that make it attractive for a wide range of applications ranging from solid oxide fuel cell, to three way catalysts gas sensors, etc. Although several methods have been proposed for the synthesis of ultrafine powders, the majority of them do not allow the production of powder with high specific area and they all generally require a calcination step for the crystallisation of the amorphous phase produced. Nanocrystalline ceria particles were successfully produced by one-step microwave-assisted synthesis from a glycol solution of metal nitrates under mild conditions (140?C, 1 atm). The as-prepared powder showed a good crystallinity and nanometric particle size. This simple and economic soft chemical method leads to nanometric cerium oxide with an high specific surface area suitable for catalytic applications

Criminal Justice Decision Making as a Stratification Process: The Role of Race and Stratification Resources in Pretrial Release

Our purpose is to bridge the criminal justice and stratification research literatures and to pursue the argument that homologous structural principles stratify allocation processes across central institutions of American society. The principle observed here in the making of bail decisions, as in earlier studies of the allocation of earnings, is that stratification resources operate to the greater advantage of whites than blacks. The operation of this principle is established through the estimation of covariance structure models of pretrial release decisions affecting 5660 defendants in 10 federal courts. Education and income are treated in this study as observed components of a composite construct, stratification resources, which works to the greater advantage of whites. Prior record is also found to operate to the greater advantage of whites. Two further variables, dangerousness and community ties, increase bail severity among blacks and whites. While the effect of community ties has been legally legitimized since the Bail Reform Act of 1966, the effect of dangerousness was not so legitimized until the Bail Reform Act of 1984. However, because our data precede the latter act, they confirm that this act simply reinstitutionalized earlier practice. Meanwhile, our race-specific findings may explain why although this and earlier studies find negligible main effects of race on criminal justice outcomes, black Americans nonetheless perceive more criminal injustice than do whites. In the criminal justice system, as in other spheres of American society, whites receive a better return on their resources, but our findings that the statutory severity of the offense and dangerousness work to the relative disadvantage of white defendants’ challenges conflict and labeling theory\u27s one-dimensional characterization of black defendant disadvantage

MW-Assisted polyol mediated synthesis of gadolinium-doped ceria nanopowders

Gadolinia-doped ceria (GDC) is one of the most promising electrolyte for intermediate temperature solid oxide fuel cells (SOFCs). In particular, the production of GDC as nanopowders leads to an higher reactivity that allows better performances, milder sintering conditions and lower production costs. However, nanopowders can be produced only by carefully tailoring their production process. The choice and optimization of the synthesis process is therefore a key step for the production of powders suitable for efficient SOFC components. In this work nanocrystalline GDC (Ce0.8Gd0.2O2-delta ) particles were successfully obtained by one-step microwave-assisted synthesis from a diethylene glycol solution of metal nitrates under mild conditions (170?C, 1 atm). The as-prepared powder showed good crystallinity with specific surface area of 50 m2/g. The sintering and electrochemical properties were compared with a nanometric commercial powder. The MW-produced powder showed an improved sintering behaviour and a uniform sub-micronic microstructure. Electrochemical tests for the MW-produced GDC showed at 600?C twice the conductivity of the corresponding commercial sampl

Ti/Zr/O Mixed Oxides for the Catalytic Transfer Hydrogenation of Furfural to GVL in a Liquid-Phase Continuous-Flow Reactor

This work aims to develop an efficient catalyst for the cascade reaction from furfural to y-valerolactone in a liquid-phase continuous reactor. This process requires both Lewis and Brønsted acidity; hence, a bifunctional catalyst is necessary to complete the one-pot reaction. Ti/Zr/O mixed oxide-based catalysts were chosen to this end as balancing metal oxide composition allows the acidity characteristics of the overall material to be modulated. Oxides with different compositions were then synthesized using the co-precipitation method. After characterization via porosimetry and NH3-TPD, the catalyst with equimolar quantities of the two components was demonstrated to be the best one in terms of superficial area (279 m2/g) and acid site density (0.67 mmol/g). The synthesized materials were then tested using a plug flow reactor at 180 C, with a 10 min contact time. Ti/Zr/O (1:1) was demonstrated to be the most promising catalyst during the recycling tests as it allowed obtaining the highest selectivities in the desired products (about 45% in furfuryl isopropyl ether and 20% in y-valerolactone) contemporaneously with 100% furfural conversion

The Evaluation of the Effects of Dietary Vitamin E or Selenium on Lipid Oxidation in Rabbit Hamburgers: Comparing TBARS and Hexanal SPME-GC Analyses

The effects and specificity of dietary supplementation of EconomasETM (EcoE), mainly consisting of organic selenium (0.15 or 0.30 mg/kg feed; Se) or of vitamin E (100 or 200 mg/kg feed; VE), on lipid oxidation were evaluated in rabbit hamburgers during refrigerated storage. Oxidation data obtained by thiobarbituric acid-reactive substances (TBARS) spectrophotometric analysis and solid-phase microextraction (SPME) coupled with gas chromatography (GC) to determine hexanal content were compared. The relationships between oxidation levels, colour and pH and the discriminability of EcoE- or VE-treatment compared with control were also examined. TBARS content decreased in both VE and EcoE groups, while hexanal showed lower values only in the VE100 dietary group. The colour parameters were compatible with acceptable product quality and seemed to parallel the TBARS values up to the second day storage. Both VE and EcoE improved oxidative stability without affecting the sensory properties, but the VE effect appeared to more specifically hamper lipid oxidation, as evidenced by the determination and quantification of hexanal, a specific product of fatty acid peroxidation