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[Display omitted] • Catalyst-assisted chemical looping process was proposed for low-carbon H 2 generation. • Achieved 99.99% purity H 2 production from biomass. • Oxygen carrier is reduced to Fe0 while coke be avoided at the CH 4 /CO 2 ratio is 0.2–0.8. • Achieved 2.93 mmole H 2 per mmole CH 4 at the only Fe and FeO are left in the reactor. Hydrogen is playing an increasingly larger role in carbon neutrality. However, efficient and sustainable hydrogen production from renewable resources suffers from unwanted side reactions and kinetic inefficiencies. Here, we study a low carbon and renewable H 2 production route that integrated biomass-derived gas dry reforming couples chemical looping water splitting process (DR-CLWS). This process requires neither removal of CO 2 from upstream biomass-derived gas, nor downstream H 2 purification and CO 2 separation, hence achieving a great level of process intensification. The reforming temperature, CH 4 /CO 2 ratio, oxygen carrier reduction temperature, reduction behavior, types of fuel gas and oxygen carriers, H 2 production, oxygen carrier regeneration and process cyclability were investigated, respectively. The coupling process resulted in higher CH 4 conversion (near 100%) and inherently CO 2 separation. CO-free H 2 was produced due to no carbon being carried over from the reduction cycle to the H 2 production cycle. Meanwhile, H 2 yields up to 2.93 mmole per mmole CH 4. Mass balance analysis reveals that the process can be operated auto-thermal without costly oxygen production or without mixing air with carbon-containing fuel gases. Moreover, the cyclability results showed that the oxygen carrier remained its activity over 265 redox cycles. [ABSTRACT FROM AUTHOR]

Heavy metals such as cadmium (Cd) in farmland soil not only affect crop production, but also endanger human health through the food chain. Rice is the main food crop with the strongest ability to absorb Cd, remediation techniques to reduce soil uptake and grain accumulation of Cd are urgently required, for which the application of foliar spraying seems to be a convenient and auspicious method. This study clarified the effects of nitrogen (N), zinc (Zn), 24-epibrassionlide (EBL) and their combined application on the growth performance and physiological characteristics of Cd and Zn in rice plants under Cd stress. Experimental results showed that N and its combination with Zn, EBL treatments promoted rice growth and yield, especially raised the yield level by 81.12% under N + EBL treatment. Additionally, three EBL treatments (EBL, N + EBL, Zn + EBL) significantly reduced the TF values of Cd in TF stems-grains , TF leaves-grains and TF glumes-grains by 42.70%, 43.67% and 50.33%, while the EF soil-roots under Zn and N + Zn treatments was the lowest, which decreased by 55.39% and 57.71%, respectively. Further, the application of N, Zn, EBL and their combined treatments significantly increased glutathione (GSH) and phytochelatins (PCs) content as well as enhanced Cd distribute into cell walls of rice shoots and roots by 15.18% and 13.20%, respectively. In addition, N, Zn, EBL and their combined application increased Zn concentration, free amino acid and glutelin content, and decreased the Cd accumulation in albumin, glutelin and globulin, thus lowered Cd concentration in grains by 27.55%, 58.29% and 51.56%, respectively. These results comprehensive suggest that the possibility of N management combined with Zn or EBL application for maintaining high yield and alleviating Cd stress by regulating the absorption and remobilization process under mild stress. [Display omitted] • Effects of N-topdressing and foliar Zn/EBL on accumulation of Cd in grains were compared. • N-topdressing decreased the EF soil-roots by 52.7% and promoted plant dry matter accumulation, mainly through root function and biological dilution to cope with soil Cd stress. • Zn reduced the EF soil-roots and TF aboveground-grains by 55.4% and 38.7% respectively, competing for the absorption of Cd and inhibiting the remobilization to grain. • EBL treatments decreased the TF aboveground-grains values by 42.7% and raised PCs and GSH contents to hinder the remobilization of Cd into grains. • N/Zn/EBL decreased the Cd accumulation in albumin, glutelin and globulin, thus lowered Cd concentration in grains by 27.6%, 58.3% and 51.6%, respectively. [ABSTRACT FROM AUTHOR]

This paper will discuss the failure mechanism of high field pulsed magnets based on a failed pulsed magnet of 85 T. Firstly, the stress failure possibility is analyzed by an ANSYS-ACP finite element model. The results show that the stress failure risk is low. Then a comprehensive model including both stress failure and structural buckling is proposed and discussed. It is found that the structural buckling and stress failure would co-exist and interact with each other. The model predicts the pulsed magnet suffered from stress failure after structural buckling and finally collapsed at 79 T. The consistency of the theoretical results with that in experiments show the validity of the comprehensive model. • First comprehensive analysis including stress failure and structure buckling of pulsed magnets under biaxial Lorentz force body. • It is a typical interdisciplinary and deep study of electromagnetic devices. • The simulation results were consistent with the experimental results. • The results show that the structural buckling and over-stressing failure would co-exist in pulsed magnets. • The bad wettability of Zylon fiber by epoxy resin maybe an important factor of the buckling and failure of pulsed magnets, which will guide the improvement of pulsed magnet technology. [ABSTRACT FROM AUTHOR]

[Display omitted] • BPF-1/1 homojunction could effectively accelerated the carrier separation. • BPF-1/1 homojunction enhanced the ORR efficiency and produced the amount of •O 2 –. • BPF-1/1 showed the best photocatalytic activity compared with single material. Oxygen reduction reaction (ORR) in photocatalysis process can generate large quantities of superoxide radicals (•O 2 –) and hydroxyl radicals (•OH), so as to degrade contaminants efficiently and rapidly. However, the electrons and holes (e-/h+) of single photocatalysts are easy to combine, which limits the ORR efficiency. In this paper, BiOBr microplate (BiOBr-P)/BiOBr nanoflower (BiOBr-F) homojunction with the molar ratio of 1:1 (which was labeled as BPF-1/1) was constructed to enhance the e-/h+ separation and drive the ORR, which can be ascribed to the different work function values between BiOBr-P and BiOBr-F, thereby resulting in the generation of internal electric field (IEF) and band bending. Meanwhile, •O 2 –, •OH and hydrogen peroxide (H 2 O 2) were analyzed quantitatively, which illustrated that the BPF-1/1 homojunction could accelerate the ORR, producing more •O 2 – and •OH than BiOBr-P and BiOBr-F. Furthermore, tetracycline (TC) was utilized as the model contaminant to assess the photocatalytic performance of the studied materials. It was proved that BPF-1/1 homojunction displayed the optimum photocatalytic performance compared with BiOBr-P and BiOBr-F. Moreover, the photocatalytic reaction mechanism of BPF-1/1 homojunction photocatalyst for TC degradation was put forward under the visible light. This research offers a feasible strategy for the preparation of effective homojunctions to raise the ORR efficiency and improve the photocatalytic activity. [ABSTRACT FROM AUTHOR]

The promising approach to ensure the robustness of the road network is to identify the critical roads. Previous researches mainly focus on the identification of single critical road. Nevertheless, the impact of one road seems to be limited, and the more practical problem is to figure out the critical road combination wherein multiple roads failures may lead to the serious collapse of a road network. This paper develops a rigorous, extensible, mathematical model to identify the critical combination of roads in urban road networks for multiple disruption scenarios. Specifically, we propose a bi-level mixed-integer nonlinear problem (MINLP) model, which is challenging to solve due to its NP-hard characters. Then the transformation and linearization of constraints help simplify the formula into a single-level mixed-integer linear problem (MILP) formula. Finally, the Nguyen and Sioux Falls networks are sufficiently tested under multiple scenarios with different levels of disruption rate and travel demand. The results confirmed the validity and superiority of the proposed model. From the numerical results, it is more practical to measure the robustness of the road network than topological analysis. Besides, the most critical combination with multiple-link failures is not simply the combination of most critical roads with single-link failure, and these roads are not necessarily connected or in the neighborhood of each other. The results also correctly evaluate the impact of disconnection, which could provide advice for managers with preferences for accessibility and travel time. [ABSTRACT FROM AUTHOR]

• Inactivation of the neddylation pathway inhibits MDSC infiltration and impairs lung cancer growth. • High NEDD8 expression positively correlates with MDSC infiltration in lung adenocarcinoma. • Neddylation pathway regulates the expression of murine CXCL5 (human homolog CXCL6) via the NF-κB signaling pathway. Myeloid-derived suppressor cells (MDSCs), a population derived from immature myeloid progenitors, are present in the tumors of patients and highly protumorigenic. However, the molecular mechanisms regulating MDSC infiltration remain unclear. Neddylation pathway is overactivated in multiple cancers and has a significant role in tumor progression. We established a subcutaneous transplantation model of Lewis lung cancer in mice and showed that inactivation of neddylation pathway inhibits MDSC infiltration and impairs lung cancer growth. A high expression level of neuronal precursor cell-expressed developmentally downregulated protein 8 (NEDD8) is positively correlated with MDSC infiltration in human lung adenocarcinomas (LUADs). Moreover, inactivation of neddylation pathway inhibits the expression of murine CXCL5 (mCXCL5; human homolog CXCL6, hCXCL6), an important cytokine implicated in MDSC recruitment. Mechanistically, inactivation of neddylation pathway inhibits activity of Cullin-RING ligase 1, a typical neddylation substrate, and induces accumulation of phosphorylated IκBα and subsequent blockage of NF-κB translocation, thus suppressing transcriptional activation of m Cxcl5 or h CXCL6. Collectively, our data suggest that neddylation-NF-κB-mCXCL5 axis is involved in MDSC recruitment to the tumor sites and demonstrate that neddylation pathway is a good therapeutic target for patients with LUAD, particularly those receiving anti-MDSC therapy. [ABSTRACT FROM AUTHOR]

• Demonstration of a stator-rotor vortex chamber (STARVOC) • Improved solids loading and reduced gas consumption relative to GSVR. • Bed behavior and pressure drop investigated to characterize gas–solid hydrodynamics. The gas–solid vortex reactor (GSVR) has enormous process intensification potential. However the huge gas consumption can be a serious disadvantage for the GSVR in some applications such as fast pyrolysis. In this work, we demonstrate a recent novel design, where a stator-rotor vortex chamber (STARVOC) is driven by the fluid's kinetic energy, to decouple the solids bed rotation and gas. Gas-solid fluidization by using air and monosized aluminum balls was performed to investigate the hydrodynamics. A constructed fluidization flow regime map for a fixed solids loading of 100 g shows that the bed can only be fluidized for a rotation speed between 200 and 400 RPM. Below 200 RPM, particles settle down on the bottom plate and cannot form a stable bed due to inertia and friction. Above 400 RPM, the bed cannot be fluidized with superficial velocities up to 1.8 m/s (air flow rate of 90 Nm3/h). The bed thickness shows some non-uniformities, being smaller at the top of the bed than at the bottom counterpart. However by increasing the air flow rate or rotation speed the axial nonuniformity can be resolved. The bed pressure drop first increases with increasing gas flow rate and then levels off, showing similar characteristics as conventional fluidized beds. Theoretical pressure drops calculated from mathematical models such as Kao et al. model agree well with experimental measurements. Particle velocity discrepancies between the top and bottom particles reveal that the impact of gravity cannot be completely neglected. Design guidelines and possible applications for further development of STARVOC concept are proposed based on fundamental data provided in this work. [ABSTRACT FROM AUTHOR]

With the increasing penetration rate of electric vehicles, the fast charging demands of electric vehicles will have a significant influence on the operation of coupled power-transportation networks. To promote the interests of the coupled system, fast charging stations, and electric vehicle users, in this paper, a multi-objective system-level fast charging station recommendation method is proposed to dynamically allocate electric vehicles to suitable stations. The recommendation problem is formulated as a sequential decision-making problem and a deep reinforcement learning method is adopted. To deal with the network-structure coupled system states, graph attention networks are introduced. Considering the heterogeneity between entities, we propose a physical connection-based graph formulation method with feature projection to integrate multi-dimensional information from charging stations, traffic nodes, and power grid buses into a graph. The graph convolution of coupled system states can then be realized to promote environment perception. Besides, to address the long time-delay action execution in recommendation problem, a double-prioritized DQN(λ) training mechanism is developed to update the guidance strategy, where an attention-prioritized cache construction method is proposed to improve the training efficiency cooperated with prioritized experience replay. The proposed graph reinforcement learning method is trained and evaluated in a joint power-transportation simulation platform. Simulation results show that the proposed strategy can promote the interest of multiple facets in coupled power-transportation networks by handling the requests in a real-time manner. Its feasibility and robustness in the urban transportation systems are also demonstrated. • The intelligent fast charging station recommendation method is explored. • Graph attention networks are introduced to extract features of the coupled system. • DQN(λ) under a double-prioritized training method is adopted to recommend. • The proposed method can promote the long-term benefit in a real-time manner. [ABSTRACT FROM AUTHOR]

• A new real option investment decision model is proposed based on the technology learning effect. • The component-based two-factor technology learning curve approach is developed to predict the component costs. • The oil price needs to be 80 $/barrel to trigger immediate investment for CO 2 -EOR. • The methanol price needs to be over 580 $/ton o trigger immediate investment for CO 2 -MET. • The CO 2 -MET project has more economical and geographical flexibilities than that of the CO 2 -EOR project. Carbon Capture and Utilization (CCU) technologies are crucial to achieving carbon neutrality targets. However, assessing the investment value and timing comprehensively is still challenging for CCU due to uncertainties in technologies and markets from a long-term perspective. In order to assist decision making, this work develops a new real option investment decision model based on the technology learning effect. In particular, the component-based two-factor technology learning curve approach is proposed to predict the future costs for each component. To verify this model, it is used to analyze two CCU processes, including the enhanced oil recovery using CO 2 (CO 2 -EOR) and methanol synthesis from captured CO 2 (CO 2 -MET). Results show that the proposed model can effectively predict the technology cost curve and find the optimal investment decision for the two applications considering various uncertainties. It is also found that the oil price at least needs to be over 80 $/barrel for CO 2 -EOR and the methanol price needs to be over 580 $/ton for CO 2 -MET respectively to trigger immediate investment. Comparatively, investing in CO 2 -MET projects is more economical than in CO 2 -EOR projects. [ABSTRACT FROM AUTHOR]

• To the best of our knowledge, we are one of the first to design a DRL policy extraction framework for power system control problems. • We propose a novel method called IGR-WODT used for policy extraction. • For the challenge of selecting the best policy, we define three metrics named policy fidelity, policy performance, and model complexity. • State-of-the-art performance is achieved on the case study of the power system emergency control problem. Deep reinforcement learning (DRL) algorithms have successfully solved many challenging problems in various power system control scenarios. However, their decision-making process is usually regarded as black-boxes. Furthermore, how DRL models interact with human intelligence remains an open problem. Thus, this paper proposes a policy extraction framework to extract a complex DRL model into an explainable policy. This framework includes three parts: 1) DRL training and data generation. We train an agent for a specific control task and generate data, which contains the control policy of the agent. 2) Policy extraction. We propose an information gain rate based weighted oblique decision tree (IGR-WODT) for DRL policy extraction. 3) Policy evaluation. We define three metrics to evaluate the performance of the proposed approach. A case study for the under-voltage load shedding problem shows that the IGR-WODT presents a performance enhancement compared with DRL, weighted oblique decision tree, and univariate decision tree. The proposed policy extraction method could provide an intuitive explanation of the neural network decision-making process to the dispatchers when making final decisions on power grid operation. Also, the resulted rule-based controller could replace the deep neural network-based controller in many field edge devices with limited computing resources, providing comparable performance. [ABSTRACT FROM AUTHOR]

This article contributes to the existing literature by examining the nonlinear relationship between industrial structure, energy intensity and environmental efficiency across developed and developing countries by utilizing three sectors of industry i.e., Primary, Secondary and Tertiary industry. Panel data includes 64 Belt and Road Initiative (BRI) from 2000 to 2017, which are further divided into two groups of developed and developing countries. SBM-DEA model is employed to measure the environmental efficiency. Random effect (RE) and Fixed effect (FE) models are employed as basic estimating techniques, while IV-GMM (Generalized Method of Moments) is utilized as robust estimator to handle endogeneity problem. The results of SBM-DEA model show that the environmental efficiency of BRI countries has deteriorated over the years. However, developed countries have the higher average environmental efficiency than developing countries. The results further show that all three sectors of industry deteriorate environmental efficiency. However, the negative impact of secondary industry on environment is more severe than primary and tertiary industry particularly across developing countries. Furthermore, a nonlinear U-shaped curve is confirmed only between secondary industry and environmental efficiency across developed countries. Our findings suggest that adopting industrial agglomeration approach and restructuring energy system can improve environmental efficiency. • Explored the nonlinear nexus between industrial structure and environmental efficiency. • Industrial structure deteriorates environmental efficiency. • The negative impact of secondary industry on environment is more severe. [ABSTRACT FROM AUTHOR]

The products of isobutane/butene alkylation are ideal high-octane blending components of gasoline pool. Binary mixtures of acidic imidazolium ionic liquids [C n MIm][OTf] (n = 4, 6, 8) and H 2 SO 4 were used to catalyze isobutane/butane alkylation in a microreactor integrated with staggered herringbone grooves. The mixing behaviors of acid and hydrocarbons were simulated in the microchannel configured with micromixing elements by computational fluid dynamics (CFD) simulation. [C n MIm][OTf]/H 2 SO 4 showed better catalytic performance than H 2 SO 4 solely. Especially the [OMIm][OTf]/H 2 SO 4 showed excellent performance. In the designed microreactor, the alkylate with research octane number (RON) of 99.5 was obtained at 10.0°C and reaction time of 81 s with [OMIm][OTf]/H 2 SO 4 as catalyst. The results are better than currently available research works implemented in batch reactors. The catalyst [OMIm][OTf]/H 2 SO 4 was recycled 14 times without reducing the catalytic activity. It indicates that the composite catalysts possess excellent reutilization performance. [Display omitted]. [ABSTRACT FROM AUTHOR]

Proppants play an important role to increase oil and gas output in shale oil and gas development process. Tracers are used to study the degree of heterogeneity and dynamic equivalence between injection and production wells to judge the state of oil reservoir. However, it is difficult to integrate both slow-release tracing and shale supporting functions in one material. The development of functional coated proppants with tracer slow-release function is of great significance. Here a simple method is developed to introduce a carbon quantum dots (CQDs) into polyvinyl alcohol (PVA) coated proppants and fabricate novel self-suspension proppants with tracer slow-release function. The PVA coating layer on ceramic proppants achieves the self-suspension ability. In the well, the PVA film melted in fracturing fluid and the CQDs were released as a tracer for downhole monitoring. The surface adhesion force of PVA-CQDs coated proppants is 2 times larger than that of ordinary ceramic proppants, and the liquid conductivity of the self-suspension slow-release tracer proppants (SSTP) can reach 51 D cm, which is 22.45% higher than original ceramic proppants at the closure pressure of 40 MPa. This work combined the coated proppants with the quantum dot tracer and obtained a new type of coated proppants with tracer slow-release function, which has a promising significance to improve oil and gas production and conducting cross-well monitoring. • Proppants with slow-release tracing function and high self-suspension performance has been firstly fabricated. • Carbon quantum dots (CQDs) act as the tracer for the first time in self-suspension slow-release tracer proppants (SSTP). • Polyvinyl alcohol (PVA) coating layer on ceramic proppants provides the self-suspension ability. • The liquid conductivity of SSTP is 22.45% higher than original ceramic proppants at the closure pressure of 40 MPa. [ABSTRACT FROM AUTHOR]

● A facile sol-gel method is first proposed to synthesize NASICON-type Li 2 Zn 2 (MoO 4) 3 and Li 2 Cu 2 (MoO 4) 3. ● Rietveld refinement indicated the structure evolution in Cu-doped Li 2 Zn 2−x Cu x (MoO 4) 3. ● The Li 2 Zn 2 (MoO 4) 3 and Li 2 Cu 2 (MoO 4) 3 electrode display excellent lithium storage performance. ● In-situ XRD confirmed the existence of mesophase Li 4 MoO 5 in Li 2 M 2 (MoO 4) 3 (M=Zn, Cu) during the initial lithium insertion. NASICON (Na superionic conductor) type electrode materials are known for their wide range of electrochemical potentials, high ionic conductivity, and most importantly their structural and thermal stabilities. Li 2 M 2 (MoO 4) 3 (M=Zn, Cu), belonging to molybdenum-based NASICON family, are successfully synthesized by simple sol-gel method. The structure evolution caused by the substitution of Zn2+ by Cu2+ within Li 2 Zn 2- x Cu x (MoO 4) 3 (0 ≤ x ≤ 2) has been investigated. Rietveld refinement results reveals that the priority order of copper atoms replacing zinc atoms in Li 2 Zn 2 (MoO 4) 3. Furthermore, both Li 2 Zn 2 (MoO 4) 3 and Li 2 Cu 2 (MoO 4) 3 electrodes deliver excellent electrochemical performance, and high reversible capacities of 864 mAh g−1 and 747 mAh g−1 can be acquired at a current density of 0.1 A g−1, respectively. In addition, the in-operando X-ray diffraction measurements indicate the formation of cubic mesophase Li 4 MoO 5 both in Li 2 Zn 2 (MoO 4) 3 and Li 2 Cu 2 (MoO 4) 3 during the initial lithium insertion, which irreversibly converts into the amorphous phases on further discharge at subsequent discharge and charge process. [ABSTRACT FROM AUTHOR]

• Process intensification abilities of a gas–liquid vortex reactor are assessed. • High-speed imaging and cross correlation reveal the detailed liquid hydrodynamics. • High turbulent dissipation zones ensure efficient micromixing and mass transfer. A gas–liquid vortex reactor (GLVR) is considered one of the promising Process-Intensified Equipment for applications that require high mixing and mass transfer efficiency. To gain understanding of the fundamentals of GLVR operation, the gas–liquid hydrodynamics in the GLVR has been investigated by high-speed imaging, digital images analysis and cross correlation. Gas bubbles and liquid ligaments are observed in the GLVR over a wide operating window. The dynamic liquid layer thickness in the GLVR chamber varies in the range of 26–36 mm. The instantaneous and time-average velocity fields of the liquid phase are obtained with a guaranteed high signal-to-noise ratio (cross correlation peak ratio higher than 10), allowing the analysis of liquid turbulent properties including the turbulent kinetic energy and its dissipation rate. Results show that the high turbulent kinetic energy dissipation rate ranging from 23 to 114 m2/s3 contributes to a high mixing and mass transfer efficiency in the GLVR. [ABSTRACT FROM AUTHOR]

• NiCo-LDH@MOFs was fabricated by an in situ semi-sacrificial template-assisted strategy. • The formation of the MOF-based 2D-2D heterostructure was first demonstrated by AFM-IR technology. • The catalysts exhibited enhanced OER catalytic activity and significantly improved stability. Ultrathin Bimetal MOF nanosheets (BMOFNs) are regarded as effective electrocatalyst for Oxygen evolution reaction (OER) because of their abundance of coordinatively unsaturated metal atoms, enhanced mass permeability and coupling effect between bimetals, while the limited conductivity and stability severely hinders their widespread application. Here, we develop an in situ semi-sacrificial template-assisted strategy to grow ultrathin BMOFNs on NiCo-LDH to construct non-noble metal electrocatalysts that are both active and stable. The optimized NiCo-LDH@MOFs heterostructure exhibits a superior electrocatalytic activity with accelerated electronic transfer and significantly enhanced durability of over 300 h. An advanced AFM-IR technology is introduced for the first time to investigate the formation of the 2D-2D heterogeneous structure in NiCo-LDH@MOFs, providing insights into the morphology-structure-composition evolution of the electrocatalyst at a nanoscale. This work demonstrates an in-situ growth strategy to achieve high-performance ultrathin MOF-based electrocatalysts, and provides advanced combinatorial characterization techniques to monitor the material growth process. [ABSTRACT FROM AUTHOR]