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The complex oxygen evolution reaction (OER) is recognized as the most studied and explored electrochemical conversion, which plays a crucial role in energy-related applications. In this work, a series of metal-organic framework (MOF)-derived FeNi oxides from a barrel-shaped Ni-based BMM-10 precursor are conveniently obtained to show an excellent OER performance. Under mild Fe(III) etching, a type of core-shell Fe

The bagasse, which is a typical agricultural and forestry waste, was employed as the silicon source to produce Li4SiO4-based ceramics with superior CO2 sorption performance. It is found that the presence of impurities elements in the bagasse ash will bring complex side reactions and form side products during the sorbent preparation process, which are extremely harmful to the performance of the synthetic sorbent. Pretreatment has been considered as an effective approach to reduce the impurities elements. In this work, the effects and mechanisms of water/acid washing pretreatments on bagasse ash were firstly detailed investigate and compared. The results indicate that the hydrochloric acid washing pretreatment can effectively remove the residual metals (Ca, Fe, etc.) in the sample in addition to the water-soluble impurities (K, P, S, etc.). The maximum sorption capacity of sorbent synthesized by the acid washing pretreatment is about 0.32 g/g sorbent and the superior performance can be well maintained over 10 cycles. A novel technical route utilizing the ash from biomass power plants for in-situ CO2 capture has been developed, which has great potential for carbon capture in the future.

Li4SiO4-based adsorbent is considered as a promising choice for the CO2 removal from power plants’ flue gases. However, the relatively high raw materials cost still limits its industrial applications. In this work, aiming to reduce the cost of Si-source, three novel natural occurring minerals including the pumicestone, the montmorillonite and the attapulgite were employed as Si-sources for the production of Li4SiO4-based adsorbents. The phase composition, surface morphology as well as the cyclic CO2 ad-desorption performance of obtained adsorbents were experimentally and kinetically investigated. It is found that the Si content of minerals directly determines the adsorption capacity of adsorbents, resulting in a relatively high and stable capacity of nearly 0.1 g/g within 22 cycles for the pumicestone derived adsorbent compared with other adsorbents obtained from minerals. Moreover, the excess Ca inside the minerals is found forming CaO, which is harmful to the desorption performance of adsorbent owing to the occurrence of Li–Ca–CO2 interactions. As a consequence, Si-source with high Ca content was proven inadaptable for the synthesis of Li4SiO4-based adsorbent, which provides guidance for the future selection of mineral Si-sources in this field.

Eutectic doping has been considered one of the most efficient and economic approaches to modify Li4SiO4-based CO2 adsorbents. Nevertheless, neither systematic screening nor selection criteria have been provided for the prediction of potential dopants. Hence, in this work, 12 kinds of molten salt dopants, including 5 unreported, were systematically compared and screened. First, the feasibility of candidates was evaluated, and unsuitable options were excluded after clarifying the detailed reasons such as volatilization loss and decomposition. Then, the capacity enhancing effects as well as the economies of residual dopants were calculated and the optimal option, NaF, which possesses the highest capacity enhancement of 0.45 g CO2 per g dopant and one of the best economies of 375.0–642.9 g CO2 per $, was eventually screened out. The modification effect of dopants was further investigated to reveal a strong relationship with their eutectic temperature, and this is the reason why L-NaF, which possesses the lowest eutectic temperature (475 °C), exhibited the greatest performance. Finally, based on the above findings, three criteria were summarized for the future selection of potential eutectic dopants, which are of great importance for the development and application of high-performance doped Li4SiO4 adsorbents.

Granulation is an effective method to mitigate the issue of CaO-based sorbent elutriation in the calcium looping process. To further enhance CO2 capture performance of CaO-based pellets, pore-formi...

Li4SiO4-based ceramic has been considered as one of the most promising candidates for high-temperature CO2 capture owing to its relatively high sorption capacity and desirable cyclic stability. Si-source is one of the most important factors affecting the cost as well as the CO2 capture performance of Li4SiO4 sorbent. In this work, naturally occurring wollastonite was firstly employed as the Si-source to produce Li4SiO4-based sorbent. The as-prepared sorbent was primarily composed of Li4SiO4 and CaO. It is believed that the enhanced CO2 capture performance was attributed to the effect of CaO as well as the occurrence of Li-Ca interactions ( L i 4 S i O 4 + C a O + C O 2 ↔ L i 2 C a S i O 4 + L i 2 C O 3 ), which were experimentally verified via in situ XRD test. As a result, the sorbent possesses a relative high capacity of ∼0.18 g/g at the initial cycles during the cyclic sorption-desorption test. However, its capacity gradually declined owing to the separation and formation of sintered CaO external shell. From the cost analysis, the as-prepared CaO-Li4SiO4 sorbent can effectively decrease the total raw material cost by reducing Li-demand. To sum up, the good comprehensive performance and relative low cost of as-prepared CaO-Li4SiO4 sorbent make it promising for its practical applications in the future.

Granulation of CaO sorbents is the prerequisite for the practical application of the calcium looping system for CO2 capture at high temperatures. This work, for the first time, proposed a simple and facile graphite-casting granulation technique to achieve the one-step pelletization of CaO-based sorbent pellets. The as-prepared pellets exhibited good sphericity and a uniform diameter distribution of 2.5–3 mm. It was found that the granulation process caused the densification of the microstructures for the sorbent, thus decreasing the surface areas and CO2 sorption performance. Hence, a porosity promoter was employed to modify the pellets, endowing the granulated sorbents with enhanced porous structures. As a result, the CO2 sorption capacity of the modified pellets was increased by 48% compared to that of the unmodified pellets over 20 sorption/desorption cycles. In addition, the cyclic performance of the pellets under 50% CO2 desorption atmospheres was also evaluated. The results showed that the presence of CO2 at the desorption stage aggravated the sintering and, thus, decreased the sorption capacity of the pellets. Nevertheless, the pellets modified by the porosity promoter still performed much better than the unmodified ones. The graphite-casting CaO pellets exhibited good mechanical properties, including compression strengths and attrition resistance, which were quite important for the practical application of CaO sorbents in circulating fluidized bed. Good chemicophysical performance demonstrates that the graphite-casting granulation technique is applicable to the preparation of CaO pellets.

A semi-industrial preparation procedure of CaO-based sorbent pellets was developed for the calcium looping process. First, Ca12Al14O33, was incorporated into CaO-based sorbents to enhance the cyclic stability via a wet mixing method. Then, spray-drying technology, was chosen to obtain well-mixed precursor powders quickly and efficiently in an industrialized mode. Finally, the CaO-based pellets were fabricated via an extrusion-spheronization method for practical industrial application and doped with three novel types of pore formers (urea, polyethylene glycol and polyvinyl alcohol). It is found that the sorbent pellets with 5 wt% urea possess the optimal CO2 uptake. Even under the oxy-fuel calcination condition, the sorbent pellets still held a 0.29 g CO2/g sorbent capacity at the 25th cycle, which was approximately 10 times as high as that of limestone pellets. Moreover, the sorbent pellets exhibited a high anti-attrition capacity, with a weight loss of below 0.8% after 3000 rotations. Therefore, the sorbent pellets derived from the foregoing semi-industrial synthesis procedure can simultaneously satisfy the requirements of cyclic sorption performance, industrial production and practical industrial application. This work provides a possibility for the production of highly efficient CaO-based sorbent pellets, to some extent, which can pave the way for the application of calcium looping process.

The highly efficient CuO-based oxygen carrier is prospectively applied in chemical-looping combustion process. The metal precursors and synthetic methods greatly affect the performance of the synthetic CuO-based oxygen carriers. The inorganic precursors are commonly used to synthesize CuO-based oxygen carriers, while the organometallic precursors are scarcely adopted. In this work, the organometallic copper precursor [copper (II) acetate] and three other different organometallic support precursors (magnesium l-lactate hydrate, silicon tetraacetate and magnesium acetate) were adopted to produce CuO-based oxygen carriers via the methods of wet-mixing and spray-drying, respectively. It is found that the synthetic oxygen carriers incorporated with inert supports (MgO and SiO2) exhibit remarkably stable redox reactivity, compared to the pure CuO. Moreover, the redox reactivity of the MgO-incorporated CuO-based oxygen carriers is superior to that of the SiO2-incorporated CuO-based oxygen carriers. It is mainly attributed to the higher Tammann temperature of MgO (1549 K) compared to that of SiO2 (937 K), which more effectively contribute CuO to inhibit particle growth and agglomeration due to sintering. Additionally, the MgO-incorporated CuO-based oxygen carriers prepared via scalable spray-drying method also exhibit the relatively high redox reactivity. It indicates that the spray-dried, synthetic CuO-based oxygen carriers from organometallic precursors possess the potential to be industrialized amplification.

Plastic/rubber waste-templated carbide slag pellets were prepared via an extrusion-spheronization method for high-temperature CO2 capture. Four types of common plastic and rubber wastes (i.e. waste plastic bottle composed of polyethylene terephthalate, disposable plastic cup composed of polypropylene, waste plastic pipe composed of polyvinyl chloride and scrap tire composed of rubber, sulfur and carbon black) were selected as the templating materials. It is found that the addition of waste plastic pipe can cause inferior CO2 capture performance for carbide slag pellets (merely 0.123 g CO2/g sorbent after 25 cycles). It is mainly attributed to the deactivation of carbide slag pellets as a result of the interaction between CaO and the chlorine released from waste plastic pipe. The other chlorine-free plastic and rubber wastes are effective to improve the cyclic CO2 capture performance of carbide slag pellets via altering their porosities. Particularly, the carbide slag pellets doped with 5 wt% of waste plastic bottle exhibit the highest CO2 capture capacity of 0.277 g CO2/g sorbent after 25 cycles, compared to 0.218 g CO2/g sorbent for carbide slag pellets. Moreover, the pre-calcination atmosphere plays an important role on the cyclic CO2 uptake of plastic/rubber waste-templated pellets. The CO2 capture capability of plastic/rubber waste-templated pellets pre-calcined in air is inferior to that pre-calcined in N2. It is mainly due to the heat released from the combustion of plastic or rubber wastes in air accelerates severe sintering for the plastic/rubber waste-templated carbide slag pellets.

This study proposes the use of multi-acidification to reactivate CaO-based sorbents and investigates the feasibility of this process under N2 or oxy-fuel (with and without SO2) calcination conditions. The multi-acidification process involves the repeated modifications of CaO-based sorbents using acid, such as the waste acid from industrial chemical processes. Under pure N2 or oxy-fuel (without SO2) calcination conditions, the multi-acidification can completely improve the adsorption capacity and capture rate of the sorbents to its original value, owing to the significantly improved physicochemical characteristics such as the grain size and surface area. Under oxy-fuel (with SO2) calcination conditions, the effectiveness of multi-acidification is limited due to the formed insoluble CaSO4. However, the introduction of filtration during multi-acidification can effectively remove CaSO4, thus recovering the adsorption capacity to its initial values.

In this work, spherical Li4SiO4 pellets were produced via an extrusion–spheronization technique. This pelletization process caused the destruction of the original porous structure, a reduction of the specific surface area and, thus, a decrease in the CO2 sorption performance. Therefore, a typical pore-forming material of microcrystalline cellulose was employed to modify the inner microstructures of the pellets and thus enhanced the cyclic CO2 sorption capacity. The pellets modified with 20 wt% microcrystalline cellulose exhibited a high capacity of 0.282 g CO2/g sorbent at the 70th cycle, which is even comparable with that of the Li4SiO4 powder. It has been indicated that the performance enhancement is attributed to the increased surface area and enriched porosity. In addition, the sorbent pellets are required to possess excellent mechanical performance for the practical application in the circulating fluidized-bed reactors; therefore, the mechanical properties, i.e., compression strength and anti-attrition performance, were also tested. The results indicated that the Li4SiO4 pellets maintained quite outstanding mechanical performance. The good physicochemical properties of the pellets show that the developed Li4SiO4-based sorbents have promising prospects for high temperature CO2 capture in fluidized-bed systems.

In this study, a novel one-step graphite moulding pelletization method was used to produce porous Li4SiO4 adsorbent pellets conveniently. The produced pellets were primarily composed of Li4SiO4 phase from X-ray diffraction analysis. The as-prepared adsorbent pellets exhibited good sphericity and a uniform diameter distribution of 2–2.5 mm. The detected porous structure resulting from the fast release of gases during the synthesis process could increase the porosity of pellets significantly and lead to a greater specific surface area of 1.02 m2/g. This pelletization method produced a high CO2 capture capacity of 0.22 g/g at the 50th cycle when the adsorption process was performed at 550 °C under 15 vol% CO2 for 30 min. Moreover, the extra contraction force due to the shrinkage during the chemical reaction of the calcination process could enhance the mechanical strength of the pellets, resulting in the high compression strength (2.84 MPa) and the superior attrition resistance (a weight loss of 6.72% after 2000 cycles). The good overall performance (i.e., CO2 capture capacity and mechanical strength) of the produced pellets in this work indicates that the graphite moulding method may be applied in the synthesis of Li4SiO4 adsorbent pellets for CO2 capture.

Li4SiO4 absorbent is one of the most promising CO2 absorbents to alleviate the global warming crisis. However, Li4SiO4 absorbents produced by the traditional solid-state method exhibit poor absorpt...

Li4SiO4 sorbents for high-temperature CO2 removal have drawn extensive attention owing to their potential application in carbon capture and storage (CCS). The major challenge in the application lies in the poor CO2 capture performance under realistic conditions of low CO2 concentrations, owing to the dense structure and poor porosity. In this work, Li4SiO4 sorbents were prepared with porous micromorphologies and large contact areas using a variety of organometallic Li-precursors, achieving fast CO2 sorption kinetics, high capacity and excellent cyclic stability at a low CO2 concentration (15 vol%). It was found that a high conversion of ~ 74% was maintained for pure Li4SiO4 even after 100 sorption/desorption cycles. Moreover, by doping with Na2CO3 to reduce the CO2 diffusion resistance, the conversion of the sorbent was further enhanced to 93.2%. The enhancement mechanism of alkali carbonate have been proven here to be ascribed to the formation of the eutectic melt of Li/Na carbonates, the existence and function of which has been confirmed in this study.

The rapid loss-in-capacity in CO2 capture is the major barrier to the application of abundantly available CaO-based natural minerals in calcium looping process. In this work, the mechanically activated method of wet ball-milling was tried to prepare highly efficient CO2 sorbents from naturally occurring dolomite. Two major operation parameters, ball-milling duration and solid-to-liquid ratio, closely affecting the characteristics of wet ball-milled dolomites were investigated. It is found that the prolongation of ball-milling duration is beneficial to improve the cyclic CO2 capture capability of wet ball-milled dolomite. The solid-to-liquid ratio of 1:1 is optimum to control the aggregation of dolomite particles during ball-milling process. Therefore, the dolomite milled with a solid-to-liquid ratio of 1:1 for 120 min exhibits highly stable CO2 capture performance under severe calcination conditions, achieving a high carbonation conversion of 74.8% in the 25th cycle. The superior CO2 capture performance of wet ball-milled dolomite is mainly attributed to the appreciably reduced particle size and preserved porous microstructure, which promote the accessibility of CO2 to the interior, free CaO.

Calcium looping process (CaL) is a promising thermochemical energy storage technology for the application in the 3rd generation concentrated solar power plants (CSP). Hence, it is necessary to develop the highly efficient CaO-based heat storage composite materials. The structurally improved, CaO-based pellets were prepared via adding cellulose as the pore-forming template. Furthermore, the approach of TiO2 incorporation was adopted aiming to enhance the anti-sintering ability of the structurally improved, CaO-based pellets. It is found that the structurally improved, TiO2-incorporated, CaO-based pellets that containing 25 wt% of TiO2 exhibit the highest CaO carbonation conversion and energy density of 57.5% and 1827.7 kJ/kg after 20 cycles, which are nearly 1.3 times as high as those of the pure Ca(OH)2 pellets. The superiority of the structurally improved, TiO2-incorporated, CaO-based pellets on cyclic heat energy storage/release is more prominent under harsh calcination conditions (950 °C, pure CO2). The evenly distributed CaTiO3 grains, providing structural stability to the CaO-based pellets and also enhancing the anti-sintering ability, are responsible for the improved cyclic energy storage/release performance. Additionally, the desirable compression strength (16.67 ± 1.05 MPa) contributes to strengthen the practicability of structurally improved, TiO2-incorporated, CaO-based pellets applied in the CaL-CSP system.

Various synthesis methods, such as the combustion method, sol–gel method, impregnated suspension, precipitation, etc., have been previously proposed for the production of efficient Li4SiO4 sorbents. During these methods, the mixture of the precursors of Li and Si were usually dried through the oven, water bath, or oil bath, which are all energy-consuming and slow processes. To produce Li4SiO4 sorbents quickly and efficiently, the spray-drying technique was employed in this work. The spray-dried sorbents exhibited both excellent CO2 capture capacity and cyclic stability during the multiple cycles, indicating that the spray-drying method was effective for the preparation of efficient and durable Li4SiO4 sorbents for high-temperature CO2 removal. Especially, the sorbent using lithium tartrate as the Li source achieved a considerable first-cycle CO2 sorption capacity of ∼0.275 g of CO2/g of sorbent and still held the capacity of ∼0.248 at the 50th sorption/desorption cycle under the realistically low CO2 conc...

Although inert supports have been proved effective to enhance CO2 capture performance of CaO sorbents, more commonly used supports are derived from expensive raw materials (such as nitrates and organometallic precursors). This work utilized cheap waste sludge from the steel plant, which is of a high daily output and has not received effective reuse, to promote the CO2 capture performance. The results showed that the sludge effectively promoted the performance of limestone. Homogeneously dispersed inert material of MgO, acting as the metal framework to resist sintering, was responsible for the enhanced performance. The introduction of waste sludge into the calcium looping could not only improve the sorbent performance, but also provide a potentially effective way to reuse the waste sludge.

For practical application in calcium looping, CaO-based sorbents need to be pelletized. However, the pelleting process, particularly the extrusion process, will lead to the loss of specific surface area, hence weakening CO2 sorption performance of sorbent pellets. In previous studies, only limited modification methods were developed for CO2 sorption performance enhancements of sorbent pellet, and the effects of modification are not satisfactory. In this work, the enhancement of CO2 sorption performance of extruded–spheronized pellets was achieved by incorporating the MgO support into CaO-based pellets. Three routines of pellet preparation were studied including soaking (routine I), mechanical mixing (routine II), and simultaneous hydration-incorporation (routine III). It was found that the sorbent pellets produced via routine III possess the best cyclic sorption performance because of the generation of additional pores within the pellets upon the release of CO2derived from the decomposition of magnesium a...

The traditional development of CaO-based sorbents to be used in calcium looping process (CLP) consists of two steps: producing powders with improved cyclic performance by sorbent modification, followed by the subsequent granulation. However, this traditional routine is complicated and energy-consuming. Moreover, the improved performance would be weakened again during the granulation process. Hence, the implement of the modification and granulation within one step to produce CaO-based sorbents is of significant importance for CLP. This work, for the first time, proposes a simple and facile gel-casting technique to achieve the one-step synthesis of highly-efficient CaO-based sorbents pellets. The pellets modified with microcrystalline cellulose (CaO-MC) achieved considerable CO 2 capture capacity of ~ 0.48 g CO 2 /g sorbent at the 25th cycle under the mild calcination condition and retained relatively excellent performance of 0.41 g/g over 25 moderate cyclic tests, higher than those of the unmodified pellets (CaO-pellet). The decomposition of microcrystalline cellulose in CaO-MC does not change the cubic crystal structure of CaO, but brings more pores that contribute a lot to its superior CO 2 capture performance. Moreover, all synthesized pellets possess good attrition resistance, indicating the applicability of the prepared pellets to the application in CLP.

High-temperature CO2 capture by using Li4SiO4-based adsorbent has been considered as an efficient approach to alleviate the global warming problem. However, the relatively low conversion and lake of suitable pelletization approach still limit the applications of Li4SiO4 in practical looping system. In this work, high-performance Nd-doped Li4SiO4-based adsorbent pellets were one-step fabricated conveniently by combining the synthesis, the pelletization and the doping processes. The physico-chemical properties as well as the CO2 capture performance of doped pellets were systematically investigated. Especially, the modification effects and mechanisms of Nd-doping were also studied in depth. The results show that triple positive effects including the pore-forming, the formation of inert sintering-resistant frameworks and the occurrence of Li4SiO4 lattice defects were introduced by Nd-doping. All of above effects lead to a stable capacity of Nd-doped pellet as high as ~0.2 g/g within 20 ad-desorption cycles, which is promising for its future applications.

It has been widely acknowledged that the Li4SiO4-based adsorbents with smaller particle size and tailored structure will certainly exhibit superior CO2 capture performance. In this work, a novel two-phase synthesis method was proposed to produce tailored micro-scale Li4SiO4-based adsorbents with ultrafast CO2 capture rate. The effects of synthetic temperature on the phase compositions, the chemical bonds, the pore structure, the surface morphology and the CO2 capture performance of obtained adsorbents were systematically investigated. It is found that the increase of temperature during synthesis process could promote the Li4SiO4 content of obtained adsorbents. Nevertheless, higher temperature also leads to the aggravation and sintering of particles, thus hindering the capacity of adsorbents. Examining the pros and cons, the adsorbent calcined at 600 °C shows the greatest morphology consisted of hollow-structured microspheres with a uniform diameter of 1–2 μm and exhibits the fastest adsorption rate as well as the highest adsorption capacity (~ 0.184 g CO2/g adsorbent within only 5 min's adsorption under 15 vol% CO2), leading to a superior Li4SiO4 conversion as high as ~80%. In a word, this two-phase method is promising in the future production of Li4SiO4-based microspheres for high-efficient and ultrafast CO2 capture.

While CaO has exhibited promising prospects and been identified as one of the best candidates for high-temperature CO2 capture, it suffers a well-known problem of loss-in-capacity; that is, its sorption capacity decays quickly with the increase of cycle numbers. In the last decade, extensive work has been conducted on the incorporation of CaO into inert solid support particles to preventing sintering and, thus, to enhance its cyclic CO2 sorption performance. With the rapid progress in this aspect, a timely review is highly required. This work summarized the state-of-the-art researches in the literature, mainly including the synthesis methods to finely disperse inert supports among CaO particles and various inert supports to prevent sintering. In addition, the effectiveness of various supports via different incorporating methods and test conditions are discussed and quantitatively compared in the current work. The highly required future development trends of synthetic CaO sorbents are also recommended in the last part of this work. We expect that this work will inspire and guide researchers from both academic and industrial communities and help pave the way for major breakthroughs in both fundamental research and industrial applications in this field.

In recent years, high-temperature post-combustion carbon capture (PCC) using regenerable lithium orthosilicate ceramics has drawn extensive attention. However, the low conversion rate of Li4SiO4 is still one of the toughest obstacles limiting its practical applications. In this work, a mechanochemical activation method was used for the modification of Li4SiO4-based adsorbents for the first time, and the physico-chemical properties of activated samples were systematically compared with that of dry-milled. It was found that the mechanochemically activated Li4SiO4 possesses higher surface area, smaller particle size and greater microstructure, resulting in a superior CO2 adsorption capacity of ~0.271 g/g after 72 min’s activation. The dry-milling has been proven to enhance the capture capacity by crushing the adsorbent and reducing its particle size. However, the modification effects of dry-milling will be limited as the increasing of milling time due to the occurrence of cold welding. In comparison, the additional modification mechanisms of mechanochemical activation process could be summarized as: (i) the water could act as the liquid agent to reduce the cold welding agglomeration and produce smaller adsorbent particles; (ii) these smaller particles provide more surface area for the occurrence of hydration reaction (Li4SiO4 + H2O ↔ Li2SiO3 + 2LiOH), resulting in a porous structure consisted with laminated LiOH crystals and thus promoting the surface area of adsorbents efficiently. In a word, the superior morphology improvement and adsorption enhancement effects of this novel activation method made it a promising method for the future modification of Li4SiO4-based adsorbents.

Rapid loss-in-capacity of naturally occurring limestone for CO2 capture is the most prominent issue in the calcium looping process. The synthesis of highly efficient sintering-resisting sorbents is a common solution to mitigate capacity decay. However, the long-term CO2 looping cycles, particularly in the presence of SO2, still cause the generation of large amounts of spent CaO-based sorbents. Comparatively, the reactivation of spent sorbent is more economical than the replenishing of fresh sorbent. In this work, three types of reactivation modes (i.e., hydration, simultaneous hydration/ impregnation and acidification) were applied to recover the CO2 capture capacities of the spent, synthetic CaO-based sorbents (CaO/MgO = 75 wt%/25 wt%). It is found that hydration is effective to recover the cyclic CO2 capture performance of the spent sorbent due to the formation of more cracks and channels that extend to the interior of sorbent particles. Therefore, the sorbent reactivated via sole hydration exhibits a high capacity of 0.390 g/g after 40 cycles. Moreover, NaCl impregnation combined with hydration produce lager amounts of macropores within the reactivated sorbents after initial sever sintering that are responsible for their desirable CO2 capture stability. The introduction of filtration during acidification reactivation process can effectively enhance the initial CO2 capture capacity (an improvement percentage of ~14.7%) owing to the removal of the irreversible CaSO4.

Recent studies have revealed that circular RNAs (circRNAs) play important roles in the tumorigenesis of human cancer, including hepatocellular carcinoma (HCC). In present study, we screen the circular RNA expression profiles in HCC tissue and investigate the molecular roles on HCC tumorigenesis. Human circRNA microarray analysis showed there were total 1,245 differently expressed circular RNAs, including 756 up-regulated circRNAs and 489 down-regulated circRNAs, in three pairs of HCC tissue and adjacent normal tissue. Hsa_circ_0016788 was identified to be up-regulated in both HCC tissue and cell lines. Loss-of-functional experiments in vivo and vitro revealed that hsa_circ_0016788 silencing inhibited the proliferation, invasion and promoted the apoptosis in vitro, and inhibited the tumor growth in vivo. Bioinformatics tools and luciferase reporter assay validated that miR-486 targeted hsa_circ_0016788 and CDK4 accompanying with negatively correlated expression, suggesting the hsa_circ_0016788/miR-486/CDK4 pathway. Receiver operating characteristic (ROC) curve showed that hsa_circ_0016788 had high diagnostic value (AUC = 0.851). In summary, results reveal the role of hsa_circ_0016788/miR-486/CDK4 in HCC tumorigenesis, providing a novel therapeutic target for HCC.

The rapid loss-in-capacity and severe attrition are easily encountered for CaO-based sorbent during multiple CO2 capture cycles. It is necessary to prepare the CaO-based CO2 capture sorbent with high capability for CO2 uptake and attrition resisting. In this work, the TiO2-decorated CaO-based sorbent pellets were prepared via extrusion-spheronization, and three different modification modes (i.e., dry-mixing, wet-mixing and hydration-mixing) were applied. This paper lay emphasis on investigating the modification mode on affecting the cyclic CO2 uptake and anti-attrition ability of TiO2-decorated CaO-based sorbent pellets. It is found that hydration-mixing is superior to dry-mixing and wet-mixing on modifying the CO2 capture performance of TiO2-decorated CaO-based sorbent pellets. The TiO2-decorated CaO-based sorbent pellets containing 20 wt% of TiO2 prepared via hydration-mixing exhibit the highest 25th carbonation conversion of 53.44% and a desirable anti-attrition ability (a weight loss of 0.62% after 3000 rotations). The alleviated sorbent sintering as a result of the homogeneously distributed CaTiO3 phase is responsible for the improved CO2 capture performance. Additionally, the strong binding force of the initially formed hydrate contributes to enhancing the anti-attrition ability of the TiO2-decorated CaO-based sorbent pellets prepared via hydration-mixing.

The autonomous execution of mobile manipulation tasks in unstructured, dynamic environments requires the consideration of various motion constraints. The task itself imposes constraints, of course, but so do the kinematic and dynamic limitations of the manipulator, unpredictably moving obstacles, and the global connectivity of the workspace. All of these constraints need to be updated continuously in response to sensor feedback. We present the elastic roadmap framework, a novel feedback motion planning approach capable of satisfying all of these motion constraints and their respective feedback requirements. This framework is validated in simulation and real-world experiments using a mobile manipulation platform and a stationary manipulator.

The general trend of three elements (precipitation, runoff and evaporation) of the water balance of the Changjiang River Basin is discussed from the regional distribution of the mean annual values of view, i.e. isogram. The distribution of precipitation is non-uniform. The distribution of runoff mainly supplied from precipitation is more uniform than that of precipitation. The distribution of the evaporation from land is much more uniform than that of precipitation and runoff. Time distribution of these three elements shows the characteristics of comparatively distinct yearly variation and few variation between years. The relationship between precipitation and runoff, and between precipitation and evaporation in the humid region in the Changjiang River is analyzed. The slopes of their straight line correlation are nearly equal. The internal relationship between variables should be paid attention to, otherwise, a pseudo correlation may be resulted in. The paper provides the method of quantitative computation and general conclusion of probability between the regions and the whole basin. The empirical formulae based on certain inference are tested with the data of the Changjiang River.