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To address the CO 2 accumulation in atmosphere, various initiatives have been proposed, among which CO 2 capture and utilization (CCU) is regarded as an appealing strategy to reconcile carbon emission and resource utilization. Especially, integrated CO 2 capture and utilization (ICCU), i.e. performing CO 2 capture and in-situ conversion can circumvent the energy-intensive CO 2 desorption step and thus facilitate establishing step- and energy-efficient process, rendering the conversion at mild conditions particularly at low pressure due to substantial activation upon CO 2 uptake. However, CO 2 capture and in-situ conversion is not the simple add-up of these two processes. Its successful implementation relies on the harmonization of CO 2 capture reagents, substrates and the corresponding catalysts. By far, tremendous efforts have been made in this field and a plethora of CO 2 capture reagents including inorganic bases, organic bases, ionic liquids and carbonaceous materials have been utilized to capture CO 2 and the conversion protocols such as hydrogenation, cycloaddition, carboxylative cyclization etc. have been explored for these captured CO 2. As a result, the valuable products containing methanol, methane, carbonates, carbamates, oxazolidinones, ureas, and quinazolinone have been obtained from CO 2 and more importantly, the CO 2 chemistry theory is also enriched via investigating the structure and reactivity of the captured CO 2 in various reactions. In this review, we summarize the progress on CO 2 capture and in-situ conversion based on the reaction types and corresponding CO 2 absorbents. It's hoped that this review can shed light on the design of CO 2 capture and in-situ conversion and inspire the further development of this field. • CO 2 capture and in-situ conversion is an important strategy for CO 2 utilization. • Its implementation relays on the convergence of sorbents and catalyst. • Organic and inorganic base, ionic liquids are efficient sorbents in this strategy. • Both reductive and nonreductive CO 2 conversion have been realized. [ABSTRACT FROM AUTHOR]

Abstract: A nonparametric adaptive filtering approach is proposed in this paper. The algorithm is obtained by exploiting a time-varying step size in the traditional NLMS weight update equation. The step size is adjusted according to the square of a time-averaging estimate of the autocorrelation of a priori and a posteriori error. Therefore, the new algorithm has more effective sense proximity to the optimum solution independent of uncorrelated measurement noise. Moreover, this algorithm has fast convergence at the early stages of adaptation and small final misadjustment at steady-state process. It works reliably and is easy to implement since the update function is nonparametric. Furthermore, the experimental results in system identification applications are presented to illustrate the principle and efficiency of the proposed algorithm. [Copyright &y& Elsevier]

[Display omitted] • Benzene ring incorporated g-C 3 N 4 microtubes are fabricated. • This material has improved light harvesting and carrier separation efficiency. • It can be applied in photocatalytic CO 2 reduction with Co(bpy) 3 Cl 2 as co-catalyst. • The catalytic system presents high efficiency and selectivity to CO. • Stability is the most attractive feature for this material. As a promising material for photocatalytic CO 2 reduction, graphitic carbon nitride (CN) and its modification has attracted significant attention. In this work, the in-plane benzene incorporated g-C 3 N 4 microtubes were fabricated via a hydrothermal self-assembly and subsequent thermal polymerization. It is revealed that introducing the π electron-rich benzene ring into the planar structure of g-C 3 N 4 can improve the availability of π electron and create the local asymmetry of heptazine structure. As a result, the separation and transportation of photogenerated charges are improved. Furthermore, the modified g-C 3 N 4 possesses relatively narrow band gap and enhances light absorption. When the in-plane benzene modified g-C 3 N 4 microtubes were applied to photocatalytic CO 2 reduction with Co(bpy) 3 Cl 2 as co-catalyst, a CO yield up to 322.66 μmol·g−1·h−1 was obtained, which was two times in comparison with the pristine g-C 3 N 4. This work confirms the effectiveness of in-plane benzene modification and 1D hollow structure formation in improving the photoelectric performance of g-C 3 N 4. Besides, it provides an efficient photocatalytic CO 2 reduction protocol with nonmetallic semiconductor material and earth-abundant metal co-catalyst. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of ricinoleic acid based non-isocyanate polyurethanes were fabricated. • Oligomeric ricinoleic acid (ORA) was designed as the key intermediate. • SnO was developed as an efficient and recyclable catalyst to access the ORA. • The polymerization degree of ORA can be regulated by reaction time. • The properties of polyurethanes can be altered by the polymerization degree of ORA. As a consequence of the great demand and extended application of polyurethanes in various fields, the development of green processes for their production and functional polyurethane materials has received widespread attention. In this regard, the biomass-derived polyurethane via the non-isocyanate route could be promising. In this work, the castor-based polyurethanes were designed and synthesized through a non-isocyanate route by employing ricinoleic acid as the starting material, in which the oligomeric ricinoleic acid (ORA) with variable average polymerization degree was used as the key intermediate. To access the ORA with different average polymerization degree, the solid Lewis acid tin(II) oxide (SnO) was developed as the efficient and recyclable catalyst and the average polymerization degree of ORA was regulated by the reaction time at 210 °C. After sequential esterification, epoxidation, cycloaddition with CO 2 and polyaddition with 1,6-hexamethylene diamine (HMDA) or isophorone diamine (IPDA), a series of polyhydroxyurethanes (PHUs) with different tensile strength and elongation at break as well as the thermal stability and the glass transition temperature were obtained depending on the type of diamine and the average polymerization degree of ORA, indicating the functional role of the polymerization degree of ORA in regulating the mechanical and thermal properties of the resulting materials. This protocol for the castor-based PHUs preparation in this work not only represents a green and sustainable way to produce bio-based material, but also provides a convenient way to change the average polymerization degree of ORA and then alter the properties of resulting polyurethanes. [ABSTRACT FROM AUTHOR]