Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

and Fuels Changzhi Li,† Xiaochen Zhao,† Aiqin Wang,† George W. Huber,†,‡ and Tao Zhang*,† †State Key Laborotary of Catalysis, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China ‡Department of Chemical and Biological Engineering, University of WisconsinMadison, Madison, Wisconsin 53706, United States

Catalytic Transformation of Lignin for the Production of Chemicals and Fuels

Peroxynitrite--the product of the diffusion-controlled reaction of nitric oxide with superoxide radical--is a short-lived oxidant species that is a potent inducer of cell death Conditions in which the reaction products of peroxynitrite have been detected and in which pharmacological inhibition of its formation or its decomposition have been shown to be of benefit include vascular diseases, ischaemia-reperfusion injury, circulatory shock, inflammation, pain and neurodegeneration In this Review, we first discuss the biochemistry and pathophysiology of peroxynitrite and then focus on pharmacological strategies to attenuate the toxic effects of peroxynitrite These include its catalytic reduction to nitrite and its isomerization to nitrate by metalloporphyrins, which have led to potential candidates for drug development for cardiovascular, inflammatory and neurodegenerative diseases

Peroxynitrite: biochemistry, pathophysiology and development of therapeutics

Cyclodextrins as pharmaceutical solubilizers.

Superoxide ion (O2•–) is of great significance as a radical species implicated in diverse chemical and biological systems. However, the chemistry knowledge of O2•– is rather scarce. In addition, numerous studies on O2•– were conducted within the latter half of the 20th century. Therefore, the current advancement in technology and instrumentation will certainly provide better insights into mechanisms and products of O2•– reactions and thus will result in new findings. This review emphasizes the state-of-the-art research on O2•– so as to enable researchers to venture into future research. It comprises the main characteristics of O2•– followed by generation methods. The reaction types of O2•– are reviewed, and its potential applications including the destruction of hazardous chemicals, synthesis of organic compounds, and many other applications are highlighted. The O2•– environmental chemistry is also discussed. The detection methods of O2•– are categorized and elaborated. Special attention is given to the f...

Superoxide Ion: Generation and Chemical Implications

The amphetamine derivative 4,5-dimethoxy-2-nitrophenyl-2-aminopropane, a positional isomer of the potent hallucinogen DON, was studied by cyclic voltammetry and polarography. The nitro compound was reduced to the corresponding hydroxylamine under the experimental conditions used.

Cathodic behavior of 4,5-dimethoxy-2-nitroamphetamine

Le 2-hydroxi-3-phenyl-6-methylpyrazine est un produit de degradation acide de l’ampicilline.On etudie la reduction polarographique de l’2-hydroxi-3-phenyl-6-methylpyrazine dans un acide dilue.Dans un milieu fortement acide, la reduction se produit par une onde irreversible a deux electrons, trois protons qui correspondent a la reduction du groupe — C = N —.La reaction se fait au moyen d’une diffusion controlee avec un coefficient de temperature de 1.83 °C —1 et une energie d’activation de 3.51 kcal mol —1 .

``Polarographic behaviour of a metabolite from ampicillin 2 — hydroxy-3-phenyl-6-methylpyrazine''.

The development and application of a differential pulse voltammetric procedure for the hydrolytic degradation kinetic study of two well-known 1,4-dihydropyridine type drugs, nitrendipine and nisoldipine are presented. The DPV procedure exhibited an adequate selectivity, repeatability and reproducibility with CV lower than 2%. The recoveries were higher than 98% with CV of 1.63% and 1.87% for nitrendipine and nisoldipine, respectively. Hydrolysis of each drug was carried out in ethanol/Britton-Robinson buffer (30/70) at different pHs and at controlled temperature of 40, 60 and 80 °C. A significant degradation was observed at alkaline pH (>pH 8) following a first order kinetic for both drugs. At pH 12 the decay constant values of 4.85×10−2 h−1 for nitrendipine and 3.18×10−2 h−1 for nisoldipine were obtained. Also, activation energies of 18 kcal/mol and 16 kcal/mol for nitrendipine and nisoldipine, respectively, were calculated. Furthermore, for the nitrendipine hydrolytic, degradation test in different solutions for parenteral use were studied. All the tested vehicles significantly increased the degradation of the drug, with the composition of solutions being the most relevant factor rather than the pH.

A selective voltammetric method to follow the hydrolytic degradation of nitrendipine

Etude aux conditions physiologiques de pH et de temperature. Le glutathion reagit spontanement avec l'ampicilline. Consequences biologiques

Interaction between glutathione and ampicillin : a microcalorimetric evidence

A new AC polarographic method for the determination of pharmaceutical forms of ranitidine is proposed, based on the electroactivity of the ranitidine nitro group. Individual and composite assays as well as recovery studies are described. Results show adequate precision and accuracy. Sample preparation is easy and no excipient separation is required.

Juan A. Squella

Papers

Cathodic behavior of 4,5-dimethoxy-2-nitroamphetamine

``Polarographic behaviour of a metabolite from ampicillin 2 — hydroxy-3-phenyl-6-methylpyrazine''.

A selective voltammetric method to follow the hydrolytic degradation of nitrendipine

Interaction between glutathione and ampicillin : a microcalorimetric evidence

Simple determination of ranitidine in dosage forms by in-phase selective AC polarography.