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

Electrochemical Characterization of Nitrocoumarin-modified Nanostructured Electrode Platforms: New precursors for the electrocatalysis of NADH

A systematic study of a new series of 4-methyl-1,4-dihydropyridine derivatives by HPLC by both photodiode array and electrochemical detectors is reported. The optimum mobile phase was acetonitrile 0.05 M phosphate buffer pH 3 (55/45, v/v) at a flow-rate of 1.5 mL/min. Compounds I–VIII were determined with UV detection at 250 nm and by electrochemical detection at + 1200 mV. Retention times varied between 3.0 and 14.0 minutes in the optimal experimental conditions. Good linear relationships between the peak areas and concentration were found, with limits of quantification ranging between 1 x 10−8 M and 1 x 10−6 M. Repeatability studies showed average variation coefficients lower than 1% for a photodiode array detector. No significant differences between the detectors in sensitivity and selectivity were found. Also, we used different degradation trials to test the selectivity of the methods. Results of these experiments revealed that the developed methods exhibited a good selectivity.

Systematic HPLC study of a new series of 4-methyl-1,4-dihydropyridines with antitrombotic activity

A DPP study of ranitidine permeability

The radical-scavenging ability of synthesized C4-phenolic-substituted 1,4-dihydropyridines (1,4-DHPs) toward 2,2-diphenyl-1-picrylhydrazyl (DPPH•) and alkyl/alkylperoxyl ABAP-derived radicals at pH 7.4 was assessed by UV–visible spectroscopy. Reactivity of 1,4-DHPs toward DPPH• was measured by following the decay of the absorption corresponding to the radical λmax at 525 nm, permitting the calculation of EC50, tEC50, and antiradical efficiency values. Pseudo–first-order kinetic rate constants for the reactivity between the C4-phenolic-substituted 1,4-DHP compounds and alkyl/alkylperoxyl ABAP-derived radicals were followed by the decrease in λmax at 356 nm corresponding to 1,4-DHP moiety. C4-phenolic-substituted 1,4-DHPs were more reactive toward alkyl free radicals than the other tested radicals. The 3,4,5-trihydroxyphenyl-1,4-DHP was the most reactive derivative toward this radical with a kinetic rate constant value of 513.2 s−1. Also, this derivative was the most effective toward the DPPH• radical with the lowest EC50 value (5.08 µM). Comparative studies revealed that synthesized 1,4-DHPs were more reactive than commercial 1,4-DHPs. The scavenging mechanism involves the contribution of both pharmacophores, that is, hydroxyphenyl and 1,4-DHP rings, which was supported by the identification of the reaction products. © 2012 Wiley Periodicals, Inc. Int J Chem Kinet 44: 810–820, 2012

Juan A. Squella

Papers

Electrochemical Characterization of Nitrocoumarin-modified Nanostructured Electrode Platforms: New precursors for the electrocatalysis of NADH

Systematic HPLC study of a new series of 4-methyl-1,4-dihydropyridines with antitrombotic activity

A DPP study of ranitidine permeability

Scavenging activity of C4-hydroxyphenyl- and polyhydroxyphenyl-1,4- dihydropyridines toward free radicals