The kinetics and mechanism of CeIV oxidation of the water oxidation catalyst [(bpy)2(H2O)RuIIIORuIII(OH2)(bpy)2]4+ (1, RuIIIORuIII) have been investigated by UV−visible measurements with application of global analysis. The reaction proceeds by stepwise oxidation of RuIIIORuIII to RuVORuV with oxidation of RuIVORuIII the slow step. RuVORuV has been identified as an intermediate by the appearance of its ClO4 - salt as a black suspension in concentrated solutions at 5 °C. It is the key intermediate in water oxidation. The mechanism may involve a bimolecular step and formation of a peroxo-bridged intermediate. Catalytic water oxidation is greatly retarded after just a few catalytic cycles because of anation induced by O2 evolution.

Silica gel, under various hydration conditions, was investigated using a novel calorimetric adsorption (CalAd) method. This method combines data from calorimetric and adsorption titrations of a solid surface using a small probe molecule in a noninteractive solvent. The Cal-Ad method proved to be more sensitive than other characterization techniques (e.g. temperature-programmed desorption) and calorimetric techniques. Previously, it was believed that the silica surface consisted of one type of hydrogen-bonding site. The Cal-Ad method has elucidated three hydrogenbonding sites of different strengths using pyridine as the basic probe molecule. The equilibrium constant of binding, enthalpy of binding, and number of each of these sites have been determined.

Ce(IV) oxidation of the ruthenium blue dimer leads to catalytic oxidation of water. Kinetic and spectroscopic studies have revealed evidence for RuVORuV as the active catalyst. Redox cycling occurs between RuIIIORuIII and RuVORuV via a complex sequence of coupled steps involving oxidations by Ce(IV) and second-order cross reactions of the dimer. The oxygen-evolving step is not rate determining in the catalytic cycle.

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Between March 2017 and November 2018, 54 prisoner fatal overdose cases submitted to the University of Florida Forensic Toxicology Laboratory involved synthetic cannabinoids including 5F-ADB, FUB-AMB, 5F-AMB, MDMB-FUBINACA and AB-CHMINACA. Analysis of blood and urine samples was performed at NMS Labs (Horsham, PA) by liquid chromatography/tandem mass spectrometry screening, confirmatory and quantitative methods validated according to Scientific Working Group for Forensic Toxicology guidelines. This work highlights the importance of effective communication between toxicologists and medical examiners/coroners, and the value of public-private partnerships to provide coverage while laboratories work to update instrumentation and validate their own new methods to keep up with the challenges of emerging substances.

A unified scale for predicting non-specific solvent polarity employs the physicochemical properties of solutes, such as NMR, EPR, electronic transitions, etc., and the equation Ax = S'P + W in order to produce a scale of non-specific solvating ability. This approach is successful due to the exclusion of data for systems where donor-acceptor interactions exist. In this paper, the Unified Scale is extended t o include systems in polar acceptor solvents by using the equation Ax = Paper 3/03068G

Synthetic stimulants are the largest class of novel psychoactive substances (NPS) identified each year by forensic laboratories internationally. While hundreds of these drugs appear in drug powders, only a few proliferate in use among forensically relevant populations, eventually emerging in postmortem and clinical investigations. Beta-keto-methylenedioxyamphetamines (i.e., NPS with names ending in “ylone”) are currently the most popular subclass of synthetic stimulants. Leading up to its federal scheduling in 2018, N-ethyl pentylone was the most encountered synthetic stimulant. The popularity of N-ethyl pentylone declined once it was scheduled but it was quickly replaced by eutylone (bk-EBDB), a structurally related analogue from the same family. In cases encountered between January 2019 and April 2020, eutylone was quantitatively confirmed in 83 forensic investigations, including postmortem cases and driving under the influence of drugs (DUID) cases. Matrix types included blood, urine, and tissue. Eutylone was identified in cases submitted from thirteen states, demonstrating proliferation around the United States; Florida accounted for 60% of the positive cases. The mean concentration of eutylone in postmortem blood was 1,020 ng/mL (standard deviation = ±2,242 ng/mL; median = 110 ng/mL, range = 1.2-11,000 ng/mL, n = 67). The mean concentration of eutylone in blood from DUID cases was 942 ng/mL (standard deviation = ±1,407 ng/mL; median = 140 ng/mL, range = 17-3,600 ng/mL, n = 7). This report includes cause and manner of death data for 22 postmortem cases. Further analysis of authentic human specimens revealed the presence of three eutylone metabolites, including one unique biomarker and one metabolite in common with butylone. Laboratories should be aware that eutylone may be present in cases of suspected Ecstasy, “Molly”, and/or MDMA use, causing or contributing to impairment or death.

The preparation of the novel solid acid catalyst AlC12(SG),, previously synthesized in C C 4 , has been accomplished with a sealed-tube gas-phase reaction using an extended contact time. Reactivity studies and spectroscopic investigations indicate the similarity in the catalysts prepared via the two different methods. The hydration level of the silica support, prior to use in catalyst synthesis, is examined in this work. Excessively dry silica is deficient in surface silanol (Si-OH) moieties and yields an ineffective catalyst. Exposure of this dry silica to humid air allows sufficient hydration for the preparation of an active catalyst. Calorimetric titration and spectral studies show that the Bronsted acidity of the solid gives rise to its strong acidity.