Clathrate-Based CO₂ Capture from Co₂‑Rich Natural Gas and Biogas

In this study, clathrate-based CO₂ capture was investigated in the presence of thermodynamic promoters such as tetrahydrofuran (THF) and tetra-<i>n</i>-butyl ammonium chloride (TBAC) for upgrading CO₂-rich natural gas and biogas. The phase equilibria, gas uptakes, gas composition measurements, and spectroscopic analyses of CH₄ (50%), CO₂ (50%), and promoter clathrates were examined with a primary focus on the effects of thermodynamic promoters on clathrate stability and cage filling behavior. The addition of THF and TBAC significantly enhanced the thermodynamic stability of CH₄ (50%) and CO₂ (50%) clathrates. ¹³C NMR and Raman spectroscopy clearly revealed that CO₂ and CH₄ are enclathrated in the clathrate cages. THF solutions demonstrated a faster growth rate of clathrates, but CO₂ was less selective than CH₄ in the THF clathrate phase due to the lower thermodynamic stability of the CO₂ and THF clathrate compared to the CH₄ and THF clathrate. TBAC solutions produced higher CO₂ selectivity in the semiclathrate phase due to the presence of distorted small cages, which have a strong preference for CO₂ molecules. The experimental results demonstrated that CO₂ selectivity in the clathrate phase can be influenced by the thermodynamic stability, cage shape and dimension, and cage filling behavior in the presence of thermodynamic promoters, and thus, a suitable promoter and their optimum concentration should be carefully determined in designing and operating clathrate-based CO₂ capture from natural gas or biogas

Experimental schedule and disease phenotypes of R6/2 mice.

<p>(A) Schedule for ASCs-E injection, behavior test, weight measure and brain sampling. (B) ASCs-E injection mitigated weight loss in R6/2 mouse at 12 weeks age. (C) Rotarod test showed better motor performance at 10, 11 and 12 weeks of age in ASCs-E treated R6/2 compared with control. * <i>p</i><0.05, ** <i>p</i><0.01.</p

Additional file 1: of Association between sleep duration and metabolic syndrome: a cross-sectional study

Table S1. Odds ratios (ORs)a of metabolic syndrome by sleep duration, the Health Examinees-Gem (HEXA-G) study 2009-2013b. (DOCX 32 kb

Restoration of p-Akt, CREB and PGC-1α by ASCs-E.

<p>(A) Western blot analysis confirmed that upregulation of PGC-1α, p-CREB and p-Akt in ASCs-E treated R6/2 mice brain and (B) PGC-1α and p-CREB in ASCs-E treated neuro2A cells. Bar graphs show the relative levels of protein expressions normalized to β-actin. * <i>p</i><0.05.</p

Striatal atrophy and mHtt aggregation.

<p>(A) Striatal mHtt aggregation was mitigated in ASCs-E treated group. (B) mHtt aggregation was visualized by western blot. (C) mHtt aggregation level was higher in ASCs-E treated R6/2 mouse brain compared with R6/2 control. (D) Striatum was sectioned and stained with Nissl in R6/2 mouse treated with ASCs-E or vehicle. (E) Striatum/peristriatum ratio is higher in ASCs-E injected group compared with vehicle treated group. Bar  = 100 μm, * <i>p</i><0.01.</p