A density functional theory study was carried out to evaluate different possibilities of heterogeneous CO 2 desorption in combustion/gasification reactions. First, we investigated the heterogeneous CO 2 evolution induced as a secondary reaction caused by the CO readsorption on an oxidized surface, which produces a carbonatelike surface complex. This functional group was found to decompose as CO 2 with an activation energy of 60 kcal/mol. Another possibility for heterogeneous CO 2 formation during char combustion or gasification is through the molecular O 2 chemisorption on a carbon active site of an oxidized graphene layer. The peroxy complex thus formed undergoes rearrangement into a dioxiranyl complex, C(2O). This complex can evolve as CO 2 with an activation energy of 48 kcal/mol. The CO 2 desorption is facilitated by the presence of an epoxy complex near the edge of the graphene layer. The epoxy complex undergoes transformation into a cyclic ether complex during the dioxiranyl decomposition. Transition states and energetic profiles of these decomposition reactions were determined. Variations of selected C-C, O-O, and C-O bonds were analyzed through the change in the bond orders calculated by natural bond orbital analysis. Overall, carbon oxidation reactions in the presence of epoxy functionalities are very important in the formation of heterogeneous CO 2 and of cyclic ether complexes.

Fourier transform infrared (FTIR) spectroscopy has been used for online monitoring of the gaseous products, resulting from combustion of a small amount of carbonaceous material with a high nitrogen content. The combustion experiments were carried out using a fluidized-bed reactor connected online to a FTIR gas cell. Spectra were collected every 2 s during the transient combustion reaction, and with this information, very detailed and quantitative evolution profiles for NO, N 2 O, and CO 2 were determined. This approach is an option for tracking combustion products in very fast reactions, such as those that take place in combustion reactions with enriched oxygen. The analytical methodology described herein includes sample preparation, selection of experimental parameters, and data processing. The procedure used in this research can be applied to the characterization of gaseous effluents in any continuous process.

In the present study, wood biomass from Acacia mangium and its main components (hemicellulose (xylan), cellulose, and lignin) were blended with a sub-bituminous coal in 20:80 wt % ratio and subsequently were heat-treated at 900 °C using CO2 or N2 atmospheres. The reactivity (ignition temperature and activation energy) under oxy-fuel conditions (21% O2–79% CO2) was studied by thermogravimetry (TGA). It has been observed that adding biomass or its main components to coal improved the combustion efficiency. Coal/biomass and coal/xylan/cellulose/lignin char blends showed lower ignition temperatures when they were devolatilized using CO2 instead of N2. In addition, the activation energies were lower for blends thermally treated with CO2. Differences in reactivity are discussed considering changes in physical-chemical properties characterized by SEM, N2 adsorption at −196 °C, Raman spectroscopy, and XPS.

Interindividual variability in analgesic response is at least partly due to well-characterized polymorphisms that are associated with opioid dosing and adverse outcomes. The Clinical Pharmacogenetics Implementation Consortium (CPIC) has put forward recommendations for the CYP2D6 phenotype, but the list of studied drug-gene pairs continues to grow. This clinical trial randomized chronic pain patients (n = 60), referred from primary care to pain unit care into two opioid prescribing arms, one guided by CYP2D6, μ-opioid receptor (OPRM1), and catechol-O-methyl transferase (COMT) genotypes vs. one with clinical routine. The genotype-guided treatment reduced pain intensity (76 vs. 59 mm, p < 0.01) by improving pain relief (28 vs. 48 mm, p < 0.05), increased quality of life (43 vs. 56 mm p < 0.001), and lowered the incidence of clinically relevant adverse events (3 [1–5] vs. 1 [0–2], p < 0.01) and 42% opioid dose (35 [22–61] vs. 60 [40–80] mg/day, p < 0.05) as opposed to usual prescribing arm. The final health utility score was significantly higher (0.71 [0.58–0.82] vs. 0.51 [0.13–0.67] controls, p < 0.05) by improving sleepiness and depression comorbidity, with a significant reduction of 30–34% for headache, dry mouth, nervousness, and constipation. A large-scale implementation analysis could help clinical translation, together with a pharmaco-economic evaluation.

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