The emission of carbon dioxide (CO 2 ) from fossil fuels has received worldwide attention because it has been implicated in climate change, which threatens economies and environments. Accordingly, new materials that can capture CO 2 from the burning of fossil fuels efficiently, economically, and with potential energy savings must be developed. The traditional technology for the capture of CO 2 in industry is chemical adsorption by an aqueous solution of amine, which has some advantages, such as low cost, good reactivity, and high capacity.[1] However, this process for the capture of CO 2 is highly energy intensive owing to the thermodynamic properties of water and high enthalpy of absorption.[2] It is estimated that the output of energy would drop by about 30 % when this capture technology was applied at coal-fired power plants, which significantly increases the cost of energy.[3] Currently, the goal is to design industrial attractive sorbent materials with high capacity and energy-saving for CO 2 capture.Ionic liquids (ILs) offer a new opportunity for addressing this challenge to develop novel CO 2 capture systems because of their unique properties, including negligible vapor pressures, high thermal stabilities, and tunable properties.[4] A great deal of effort has focused on the experimental and theoretical studies on the physical absorption of CO 2 in ILs.[5]The enthalpy of CO 2 physical absorption by ILs is about 20 kJ mol À1 , indicating that only a quarter energy is required to release the physical absorbed CO 2 from ILs in the regeneration step relative to amine solution method.[6] However, the absorption capacity of CO 2 by these ILs is up to about 3 mol % under atmospheric pressure. Another strategy is based on the chemisorption for CO 2 capture by task-specific ILs. Davis and co-workers [7] reported the first example of CO 2 chemisorption that employs an amino-functionalized IL; in their work, 0.5 mol CO 2 was captured per mole of IL under ambient pressure. Subsequently, some other amino-functionalized ILs, including sulfone anions with ammonium cations and amino acid anions with imidazolium or phosphonium cations, were reported for the capture of CO 2 .[8] Recently, a novel method for the capture of CO 2 in a 1:1 manner by superbase-derived protic ILs and substituted aprotic ILs using the reactivity of anion was reported.[9] Normally, the chemisorption has high absorption capacity for CO 2 along with high energy requirement for regeneration.[10] One commonly used parameter to access the regeneration energy requirement is the enthalpy of CO 2 absorption. We need reduce the enthalpy of absorption to design the energy-saving ILs for CO 2 capture. Then, how can we design suitable chemical structures of ILs to reduce the enthalpy of CO 2 chemisorption? Can we prepare highly stable ILs for energy-saving and equimolar CO 2 capture?Herein, we present a strategy to tune the enthalpy of CO 2 absorption by tunable basic ionic liquids, which were prepared by neutralizing weak proton donors with different pK a valu...

A novel strategy for SO(2) capture through multiple-site absorption in the anion of several azole-based ionic liquids is reported. An extremely high capacity of SO(2) (>3.5 mol/mol) and excellent reversibility (28 recycles) were achieved by tuning the interaction between the basic anion and acidic SO(2). Spectroscopic investigations and quantum-mechanical calculations showed that such high SO(2) capacity originates from the multiple sites of interaction between the anion and SO(2). These tunable azole-based ionic liquids with multiple sites offer significant improvements over commonly used absorbents, indicating the promise for industrial applications in acid gas separation.

The esophagus, trachea and lung develop from the embryonic foregut, yet acquire and maintain distinct tissue phenotypes. Previously, we demonstrated that the transcription factor Sox2 is necessary for foregut morphogenesis and esophagus development. We show that Sox2 is also required for the normal development of the trachea and lung. In both the embryo and adult, Sox2 is exclusively expressed in the epithelium of the trachea and airways. We use an Nkx2.5-Cre transgene and a Sox2 floxed allele to conditionally delete Sox2 in the ventral epithelial domain of the early anterior foregut, which gives rise to the future trachea and lung buds. All conditional mutants die of respiratory distress at birth, probably due to abnormal differentiation of the laryngeal and tracheal cartilage as a result of defective epithelial-mesenchymal interaction. About 60% of the mutants have a short trachea, suggesting that the primary budding site of the lung shifts anteriorly. In the tracheal epithelium of all conditional mutants there are significantly more mucus-producing cells compared with wild type, and fewer basal stem cells, ciliated and Clara cells. Differentiation of the epithelium lining the conducting airways in the lung is abnormal, suggesting that Sox2 also plays a role in the differentiation of embryonic airway progenitors into specific lineages. Conditional deletion of Sox2 was then used to test its role in adult epithelium maintenance. We found that epithelial cells, including basal stem cells, lacking Sox2 show a reduced capacity to proliferate in culture and to repair after injury in vivo. Taken together, these results define multiple roles for Sox2 in the developing and adult trachea.