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As an important part of the capital market, the stock market can not only reflect the quality of the macro economy in time, but also reflect the policy changes in the change of the stock price.In addition, the stock market not only provides a public financing platform with strong liquidity for enterprises, but also plays a crucial role in the redistribution of social resources.This paper takes China's CSI 300 index CSI 500 index from 2007 to 2022 as the research object, and uses ARIMA, ARCH family and other models to implement it, which provides a better solution for the prediction of stock trends.

Metal-organic frameworks (MOFs) provide opportunities for the design of high-efficiency catalysts attributed to their high compositional and structural tunability. Meanwhile, the huge number of MOFs poses a great challenge to experimental-intensive development of high-performance functional applications. By taking the computationally feasible and structurally representative trigonal prismatic secondary building units (SBUs) of MOFs as the entry point, we introduce a descriptor-based approach for designing high-performance MOFs for the oxygen evolution reaction (OER). The electrostatic potential-derived charge (ESPC) is identified as a robust and universal OER performance descriptor of MOFs, showing a distinct linear relationship with the onset potentials of OER elemental steps. Importantly, we establish an ESPC-based physical pattern of active site-intermediate binding strength, which interprets the rationality of ESPC as an OER performance descriptor. We further reveal that the SBUs with Ni/Cu as active site atoms while Mn/Fe/Co/Ni as spectator atoms have excellent OER activity through the variation pattern of ESPC along with metal composition. The universal correlation between ESPC and OER activity provides a rational rule for designing high-performance MOF-based OER electrocatalysts and can be easily extended to design functional MOFs for a rich variety of catalytic applications.

Large-radius non-lithium cation doping can increase lithium-ion conductivity at low lithium-ion concentrations while the doping of non-lithium cations with a small radius can improve the lithium-ion conductivity at high lithium-ion concentrations.

Deep learning techniques are being used to design new proteins by creating target backbone geometries and finding sequences that can fold into those shapes. While methods like ProteinMPNN provide an efficient algorithm for generating sequences for a given protein backbone, there is still room for improving the scope and computational efficiency of backbone generation. Here, we report a backbone hallucination protocol that uses a relaxed sequence representation. Our method enables protein backbone generation using a gradient descent driven hallucination approach and offers orders-of-magnitude efficiency enhancements over previous hallucination approaches. We designed and experimentally produced over 50 proteins, most of which expressed well in E. Coli, were soluble and adopted the desired oligomeric state along with the correct composition of secondary structure as measured by CD. Exemplarily,wedetermined 3D electron density maps using single-particle cryo EM analysis for three single-chainde-novoproteins comprising 600 AA which closely matched with the designed shape. These have no structural analogues in the protein data bank (PDB), representing potentially novel folds or arrangement of domains. Our approach broadens the scope of de novo protein design and contributes to accessibility to a wider community.

Soft robots often show a superior power-to-weight ratio using highly compliant, light-weight material, which leverages various bio-inspired body designs to generate desirable deformations for life-like motions. In this letter, given that most material used for soft robots is light-weight in general, we propose a volumetrically enhanced design strategy for soft robots, providing a novel design guideline to govern the form factor of soft robots. We present the design, modeling, and optimization of a volumetrically enhanced soft actuator (VESA) with linear and rotary motions, respectively, achieving superior force and torque output, linear and rotary displacement, and overall extension ratio per unit volume. We further explored VESA's proprioceptive sensing capability by validating the output force and torque through analytical modeling and experimental verification. Our results show that the volumetric metrics hold the potential to be used as a practical design guideline to optimize soft robots’ engineering performance

Porous carbon spheres represent an ideal family of electrode materials for supercapacitors because of the high surface area, ideal conductivity, negligible aggregation, and ability to achieve space efficient packing. However, the development of new synthetic methods towards porous carbon spheres still remains a great challenge. Herein, N-doped hollow carbon spheres with an ultrahigh surface area of 2044 m2/g have been designed based on the phenylenediamine-formaldehyde chemistry. When applied in symmetric supercapacitors with ionic electrolyte (EMIBF4), the obtained N-doped hollow carbon spheres demonstrate a high capacitance of 234 F/g, affording an ultrahigh energy density of 114.8 Wh/kg. Excellent cycling stability has also been achieved. The impressive capacitive performances make the phenylenediamine-formaldehyde resin derived N-doped carbon a promising candidate electrode material for supercapacitors.

The rise in the number of protein sequences in the post-genomic era has led to a major breakthrough in fitting generative sequence models for contact prediction, protein design, alignment, and homology search. Despite this success, the interpretability of the modeled pairwise parameters continues to be limited due to the entanglement of coevolution, phylogeny, and entropy. For contact prediction, post-correction methods have been developed to remove the contribution of entropy from the predicted contact maps. However, all remaining applications that rely on the raw parameters, lack a direct method to correct for entropy. In this paper, we investigate the origins of the entropy signal and propose a new spectral regularizer to down weight it during model fitting. We find the added regularizer to GREMLIN, a Markov Random Field or Potts model, allows for the inference of a sparse contact map without loss in precision, meanwhile improving interpretability, and resolving overfitting issues important for sequence evaluation and design.

The worldwide energy shortage has led to numerous researches for the exploration of new-type battery materials to deal with the energy crisis. To achieve a great leap in energy density, the study of high capacity electrode materials plays a major role. As a replacement to the energy accumulation system of lithium–sulfur (Li–S) and lithium–selenium (Li–Se) batteries, great concern is generated over lithium/selenium−sulfur (Li–SexSy) batteries as they combine the advantages of S (high capacity) and Se (improved electrical conductivity), consequently stands for extensive new cathode materials. In recent years, widespread researches have been conducted and great achievements have been published. This review sums up the research status on Li–SexSy batteries and concentrates on the outstanding work of SexSy cathode materials. The reaction mechanism and capacity fading mechanism are discussed. The performance-structure relationship is stated in regard of different cathode structures, including a variety of carbon hosts, conducting polymer hosts, transition metal-doped carbon electrodes and various Se/S ratio. The compatibilities of frequently-used carbonate-based and ether-based electrolyte and other new-type electrolytes for Li-SexSy battery are demonstrated. Prospects for the future developments of Li–SexSy batteries are finally proposed.

Two-dimensional (2D) metal-organic frameworks (MOFs) are promising materials for catalyzing the oxygen evolution reaction (OER) due to their abundant exposed active sites and high specific surface area. However, how to rapidly screen out highly-active 2D MOFs from numerous candidates is still a great challenge. Herein, based on the high-throughput density functional theory (DFT) calculations for 20 kinds of different transition metal-based MOFs, we propose a factor for fast screening of 2D MOFs for the OER under alkaline conditions (pH = 14.0), that is, when the Gibbs free energy change of the O-O bond formation (defined as Δ

Aqueous potassium-ion batteries (AKIBs), utilizing fast diffusion kinetics of K+ and abundant electrode resources, are an emerging technology offering high power density and low cost. Many efforts have been made by far to enhance the electrochemical performances of AKIBs, and some encouraging milestones have been achieved. To provide a deep understanding of the progress, challenges, and opportunities of the emerging AKIBs, the recent advances in both cathode and anode materials, and electrolytes of the AKIB systems are comprehensively summarized and discussed. Additionally, the research efforts on the optimization of electrode material properties, the revealing of the reaction mechanism, the design of electrolytes, and the full cell fabrication for AKIBs are highlighted. Finally, insights into opportunities and future directions for achieving high-performance AKIBs and their applications are proposed. Agency for Science, Technology and Research (A*STAR) Ministry of Education (MOE) National Research Foundation (NRF) Submitted/Accepted version This work was supported by the National Natural Science Foundation of China (51832004, 21905218), the Key Research and Development Program of Hubei Province (2021BAA070), the Natural Science Foundation of Hubei Province (2019CFA001, 2020CFB519), the Sanya Science and Education Innovation Park of Wuhan University of Technology (2021KF0019, 2020KF0019), and the Fundamental Research Funds for the Central Universities (WUT: 2020IVB034, 2020IVA036). This work was supported by the Singapore Ministry of Education Academic Research Fund Tier 2 (MOE2019-T2-2-127 and MOE-T2EP50120-0002), A*STAR under AME IRG (A2083c0062), and the Singapore National Research Foundation Competitive Research Program (NRFCRP18-2017-02). This work was supported by A*STAR under its IAF-ICP Programme I2001E0067 and the Schaeffler Hub for Advanced Research at NTU. This work was also supported by NTU-PSL Joint Lab collaboration. X. Z. gratefully acknowledges financial support from the Chinese Scholarship Council.

In this paper, the tribo-magnetization and tribological performances of the Fe(or Co, or Ni)/PTFE composites were studied. The effects of sliding velocity, normal load, and filler content on the tribo-magnetization and tribological performances of the composites were mainly discussed. The micro-morphology of the worn surfaces was investigated by scanning electron microscopy (SEM) and optical microscopy (OM) to examine the wear behavior and transfer film of the friction couples. It was found that the magnetic flux density, induced by the friction of the composites, slowly increased with the increase of load, gradually decreased with the increase of velocity, and increased with the increasing filler content. The tribo-magnetization behavior of the PTFE composites containing ferromagnetic fillers will promote the aggregation of ferromagnetic particles on the surface. Moreover, the friction and wear of the composites are reduced due to the formation and stability of the frictional transfer film.

Copper sulfide (CuS) has been proved to be a potential alternative to traditional sorbents for control of elemental mercury (Hg0) emissions downstream of the wet flue gas desulfurization (WFGD) systems. However, the detailed reaction mechanisms involved in Hg0 adsorption over CuS surface are still unclear. The density functional theory was applied to investigate Hg0 adsorption over CuS(001) surface. The results indicated that the chemisorption mechanism was responsible for Hg0 adsorption over CuS(001) surface. The formation of Hg–S and Hg–Cu bonds was confirmed by depicting the projected densities of states profiles. The binding energies of Hg0 suggested that the crystal surface with two sulfur terminations [labeled CuS(001)–S-2] exhibited a better Hg0 adsorption activity than the crystal surface with copper and sulfur terminations [labeled CuS(001)–Cu/S]. Moreover, the adsorption of the flue gas components downstream of WFGD (oxygen, sulfur dioxide, and water vapor) was studied to understand the effect o...

Porous carbons have been extensively studied in supercapacitors. However, it remains a grand challenge for porous carbons to achieve a volumetric capacitance (Cv) of over 200 F cm–3 because of the low intrinsic density and limited capacitance. Herein, we propose a pomegranate-like carbon microsphere (PCS) constructed by monodisperse, submicron, N-doped microporous carbon spheres for high-volumetric-capacitance supercapacitors. The assembly of submicron carbon spheres into pomegranate-like structures significantly reduces the required binder amount (2.0 wt %) for electrode preparation, diminishes the interparticle resistance, and most importantly, endows the PCS with a high packing density (0.75 g cm–3). Benefited from the high surface area (1477 m2 g–1), N-doping (3.0 wt %), and high packing density, the PCS demonstrates a high Cv (254 F cm–3), four times that of unassembled monodisperse carbon spheres. This work opens a new avenue to enhance the Cv of porous carbons without compromising the rate capabili...

Double shell FeOOH/PPy on a diatomite ternary complex was assembled via two-step hydrothermal and in situ polymerization routes. The polymerization process generates chemical bonding and introduces oxygen vacancies and mesopores, enhancing the conductivity and electrochemical properties of the electrodes and ensuring structural stability.

Lithium-ion capacitors (LICs) are receiving extensive attention due to their high energy/power densities. However, the imbalance in reaction kinetics between the sluggish diffusion-limited insertion anode and rapid surface-controlled capacitive cathode always leads to limited power density and poor cycling properties. Herein, yolk–shell structured orthorhombic phase Nb2O5 microspheres (YS-Nb2O5) are prepared via a scalable spray drying method employing niobium oxalate hydrate as the precursor. The as-prepared YS-Nb2O5 exhibits high specific capacity (211 mA h g−1 at 0.5C) and superior rate capability. LICs based on the YS-Nb2O5 anode and activated carbon (AC) cathode are also assembled. The YS-Nb2O5//AC LIC devices exhibit ultrahigh energy (173 W h kg−1) and power (10.8 kW kg−1) densities with ideal cycling stability (∼98% capacity retention for 1000 cycles). This work provides significant insight into the reasonable design of pseudocapacitive anode materials for high-performance LICs.

Planar mechanisms dominate modern designs of legged robots with remote actuator placement for robust agility in ground mobility. This paper presents a novel design of robotic leg modules using the Bennett linkage, driven by two coaxially arranged quasi-direct actuators capable of omnidirectional ground locomotion. The Bennett linkage belongs to a family of overconstrained linkages with three-dimensional spatial motion and unparalleled joint axes. We present the first work regarding the design, modeling, and optimization of the Bennett leg module, enabling lateral locomotion, like the crabs, that was not capable with robotic legs designed with common planar mechanisms. We further explored the concept of overconstrained robots, which is a class of advanced robots based on the design reconfiguration of the Bennett leg modules, serving as a potential direction for future research.

Accurate road network plays a very important role in urban traffic application. The traditional methods to generate road network are expensive and the update of the road network is not timely enough. With the widespread use of Global Positioning System (GPS) embedded equipment, lots of moving objects can generate a large amount of trajectory data, from which it could become possible to extract road network information. The existing road network extraction methods require different prior experiences and parameters for road networks in different regions, and the effect is not satisfactory. In this article, we propose a method to generate city road network structure based on an improved U-Net network, which can extract road network from trajectory data. More specifically, we first learn the existing road network structure and extract the feature from trajectory data, then use the improved U-Net network to infer the road centerline, finally, we postprocess its topology and generate the final road network. Our method has been validated on different trajectory datasets and achieved good visualization results.

Rattle-type Fe3O4@CuS synthesized using a two-step method was applied for elemental mercury (Hg0) adsorption in coal combustion flue gas for the first time. The Fe3O4 with strong magnetization was an ideal candidate as a core to make the sorbent recyclable, while the stabilized ultrathin CuS shell assured that the Fe3O4@CuS had a higher Brunauer–Emmett–Teller (BET) surface area with more exposed active sites and stronger magnetization. The optimal operating temperature of 75 °C allowed for the injection of the sorbent between the wet desulfurization (WFGD) and wet electrostatic precipitator (WESP), which removed the detrimental influence of nitrogen oxides. Simulated flue gas (SFG) in this section showed a slight inhibitive effect on Hg0 adsorption over the Fe3O4@CuS, mainly due to the presence of water vapor (H2O). The inhibition of H2O was proven to be the result of an active site prevention effect instead of the widely recognized competitive adsorption effect. The adsorption capacity and rate of the Fe...

Nano-ZnS particles are newly developed alternatives to activated carbons for Hg0 removal from flue gas. We investigated the Hg0 oxidation mechanisms in the presence of chlorine (Cl2) on the (110) surface of ZnS by first-principles calculations. The results show that the Cl2 molecule can dissociate into two Cl ions on the ZnS(110) surface, forming chlorinated ZnS surfaces. Compared to the clean ZnS surface, the chlorinated ZnS surface with dissociated Cl ions exhibit enhanced binding affinity over Hg0 with promoted Hg0 oxidation efficiency (Hg0 → HgCl2). The active Cl ions on ZnS surface can directly interact with Hg0 to form HgCl2, following the typical Eley–Rideal mechanism rather than the Langmuir–Hinshelwood mechanism.

CuCl2-modified carbonaceous materials have been regarded as a kind of mercury sorbent, but the Hg0 reaction mechanism over CuCl2-impregnated sorbent surface is still unclear. In this work, the binding mechanism of Hg0 on CuCl2-impregnated carbonaceous material surface was investigated using hybrid density functional theory (DFT). The results indicate that the dissociation mechanism is responsible for CuCl2 adsorption over carbonaceous material sorbent surface. The active chlorine species generated from CuCl2 adsorption can significantly enhance mercury adsorption over carbonaceous material sorbent surface. Hg0 adsorption over CuCl2-impregnated carbonaceous material surface is dominated by a chemisorption mechanism. Surface Cl and C atoms are identified as the active sites for Hg0 adsorption on CuCl2-impregnated carbonaceous material surface. CuCl2 plays an important role in mercury adsorption on CuCl2-impregnated carbonaceous materials. CuCl2 includes the following roles: (1) CuCl2 can increase the reacti...

Li2ZnSiO4 has the structural characteristics of superionic conductor for Li, but the actual measured Li conductivity is not high. Based on first-principles calculations, the Li diffusion properties of varied configurations are studied, in which Li replaces Zn with different concentrations. Particularly, topological analysis is used to obtain the possible Li interstitial sites of Li2ZnSiO4. These interstitial sites can accommodate more lithium ions and increase the concentration of lithium ions. The Li ion conductivity of the Li-doped Li2+2xZn1-xSiO4 with increased lattice Li and interstitial Li is improved dramatically. When x = 0.375, the Li ion conductivity reaches 2.006 mS/cm and the Ehull is 23 meV/atom. The mean square deviation (MSD) and probability density indicate that Li2+2xZn1-xSiO4 (x = 0.125–0.5) is a three-dimensional Li conductor. In addition, the calculation of energy band structures shows the bandgap width of 5.7 eV and 5.8 eV for Li2ZnSiO4 and Li2.5Zn0.75Si4, respectively, indicating that these materials are poor conductors of electron. These characteristics (fast Li diffusion, good phase stability, and poor electronic conductivity) make Li-doped Li2ZnSiO4 one promising solid electrolyte for solid-state Li-ion batteries.

The inevitable surface oxidation of nano-Si inhibits its practical application as anode for lithium ion battery. Here, a hierarchical electronic/ionic conducting shell is smartly constructed by self-sacrificing reaction of native oxide layer on Si nanoparticles with lithium species. The morphological observation shows that Si nanoparticles are wrapped by lithium ionic conductor Li2SiO3 and amorphous carbon as the interlayer and outer layer, respectively. Such hierarchical structure not only provides a tight bond between Si and coating layer, but also improves the interfacial stability and conductivity of Si nanoparticles. Theoretical calculations demonstrate that the adsorption of Li2SiO3 on Si (1 1 1) and the adsorption of C on Si/Li2SiO3 are exothermic and spontaneous, and that the electron transfer and ionic conductivity at the surface of Si/Li2SiO3/C composite is enhanced. As a result, the as-prepared Si/Li2SiO3/C sample exhibits outstanding cycle stability and rate capability. By optimizing the lithium sources and thickness of native oxide layer, the resulted material exhibits 2106 mAh g−1 at 200 mA g−1, remains 1583 mA g−1 at 3000 mA g−1, and maintains 70.2% of capacity retention after 200 cycles. This work provides a robust strategy to promote the practical applications of Si nanoparticles as anode for lithium ion batteries.

Environmentally benign zinc sulfide (ZnS), consisting entirely of “active” sites, has shown promising efficiency for capturing mercury from flue gas in recent experimental studies. In this work, the binding mechanism of Hg0 on the ZnS(110) surface was investigated by the density functional theory (DFT) method. Meanwhile, the binding of two additional mercury forms, HgCl and HgCl2, and three essential flue gas components, H2O, SO2, and HCl, and their further effects on the strength of Hg0 binding on the ZnS(110) surface were also evaluated. The results showed that, consistent with experimental observations, Hg0 can be chemisorbed on the ZnS(110) surface with binding energies (BEs) as high as −87.80 kJ/mol. The enhanced electrostatic characteristics on the activated surface, especially the Zn sites, are beneficial to exciting the outer-shell electrons of Hg0 and thereby enhancing the binding strength of the material. HgCl and HgCl2 were found to be chemisorbed with the highest BEs of −174.33 and −132.79 kJ/...

Traditional treatment for bone diseases limits their clinical application due to undesirable host immune rejection, limited donator sources and severe pain and suffering for patients. Bone tissue engineering therefore is expected to be a more effective way in treating bone diseases. In the present study, hybrid calcium alginate/bone powder gel-beads with a uniform size distribution, good biocompatibility and osteoinductive capability, were prepared to be used as an in-vitro niche-like matrix. The beads were optimized using 2.5% (w/v) sodium alginate solution, 4.5% (w/v) CaCl2 solution and 5.0 mg/mL bone powder using an easy-to-use method. Human ADSCs were cultured and induced into chondrocytes and osteoblasts, respectively. The cells were characterized by histological staining showing the ADSCs were able to maintain their characteristic morphology with multipotent differentiation ability. ADSCs at density of 5 × 106 cells/mL were encapsulated into the gel-beads aiming to explore cell expansion under different conditions and the osteogenic induction of ADSCs was verified by specific staining. Results demonstrated that the encapsulated ADSCs expanded 5.6 folds in 10 days under dynamic condition via spinner flask, and were able to differentiate into osteoblasts (OBs) with extensive mineralized nodules forming the bone aggregates over 3 weeks postosteogenic induction. In summary, hybrid gel-beads encapsulating ADSCs are proved to be feasible as a new method to fabricate tissue engineered bone aggregation with potential to treat skeletal injury in the near future.

Traditional two-dimensional (2D) static culture environment for stem cells followed by enzymatic cell detachment or mechanical treatment is routinely used in research laboratories. However, this method is not ideal as stem cells expand slowly, with cell damage and partial loss of specific stemness. For this reason, a better culture condition is urgently needed to improve stem cell recovery. A novel thermosensitive P(NIPAAm-co-HPM)-g-TMSPM-g-microcarrier was prepared here as a three-dimensional (3D) culture substitute. This novel microcarrier was prepared by grafting NIPAAm and HPM to the surface of glass microcarrier using TMSPM through surface free radical copolymerization. The prepared material was tested in cell culture and via cooling harvest method. We found that NIPAAm was successfully grafted on to the surface of the microcarriers, providing an excellent biocompatible environment for BMMSC adhesion and growth. More importantly, BMMSCs could be fully removed from the thermosensitive glass microcarriers with remained cell viability.

The interfacial property of cathode materials in Li-ion batteries plays a vital role for the mass transport in electrochemical process. In this paper, Li2RuO3 coating layer, acting as an electronic/ionic conductive network, is introduced to lithium-rich Mn-based material that is known for its low rate capability and quick capacity fading. The reaction kinetics are promoted due to the depolarizing effect of this modified layer. The target material achieves a discharge capacity as high as 195.4 and 150.6 mAh g−1 at 2C and 8C, respectively. The conductive Li2RuO3 coating layer helps to accelerate the transport of Li ion and electron at grain surface and relieve phase transformation, ultimately reducing the reaction resistance. Cycle stability is also enhanced (capacity retention of 92% after 100 cycles) by mitigating side reactions between cathode and electrolyte. This study provides an effective approach to ameliorate the sluggish Li-ion transport of lithium-rich Mn-based material and other analogous cathode materials.

The uncontrollable dendrite formation and infinite volume expansion bring serious safety risks and short service life to high-energy lithium (Li) metal batteries. Here, by introducing oxygen as a type of SnO2 into the Sn and carbon paper (CP) composite, a lithiophilic framework (CP/Sn/SnO2) is proposed as Li storage host for stable Li metal anode. It demonstrates that the wettability of the framework to Li can be greatly improved by partial oxidation of Sn. Then, the spontaneous reaction between the formed SnO2 and molten Li can induce the alloying of Li and Sn. Consequently, both of Sn and SnO2 in the framework finally converse to lithiophilic Li-Sn alloy as well as a small amount of lithium conductor Li2O. After molten Li injection, the prepared CP/Sn/SnO2@Li electrode achieves a dendrite-free morphology, near-zero volume change and extraordinary electrochemical performance. Furthermore, low interfacial resistance and long-term lifetime for 800 h at 1 mA cm−1 with an ultra-low voltage hysteresis of 16 mV in symmetric cells and excellent cycling stability in full cells with LiFePO4 cathode are realized. The oxygen-induced strategy provides important advancement for a stable 3D lithiophilic framework with low Li2O content in developing safe and commercial Li metal batteries.

As the dramatical improvement of Global Position System (GPS) sensors in recent years, the research of trajectory dataset has become a hotspot in the field of geographic information systems (GIS). Pretreatment is very important for extracting useful information from massive trajectory dataset. One of key problems is trajectory data compression. Aiming at preserving crucial feature of trajectories while compressing, this paper puts forward a method for compressing trajectory data that combines distance, angle, and velocity while maintaining the contour of the trajectory, especially the turning corners and U-turns in the compressed trajectory and the original trajectory. So, the compressed trajectory can be very useful for trajectory mining and road network update. The new method also shows applicability and stability through experiments on different datasets.

With the rapid development of satellite sensor technology and aerial photography technology, spatial and temporal resolution of the remote sensing image has been greatly improved. To speed up the visualization of remote sensing images, pyramid building technology is the best choice at present. However, the performance of existing methods is not as good as expected. Considering the load imbalance problem caused by the uneven data distribution problem, this paper proposes a fast tile-pyramid construction algorithm based on multilevel task parallelism. Our method changed the traditional parallel tile generation algorithm which is generated layer by layer and implemented a new algorithm that generated multiple layers at the same time by using the entire tile pyramid as a whole. Experimental results on real-life datasets show that our new algorithm can improve the construction speed of tile-pyramids.

Ceria (CeO2) based catalysts have been widely reported as potential materials for elemental mercury (Hg0) oxidation in flue gas. However, the effect of sulfur dioxide (SO2) and water vapor (H2O) on Hg0 adsorption over CeO2, which is critical for subsequent Hg0 oxidation are still unclear. The detail reaction mechanisms involved in Hg0 adsorption on CeO2(1 1 1) surface in the presence of SO2 and H2O were investigated with first-principles calculations based on density functional theory. The results suggest that SO2 was chemical adsorbed on CeO2(1 1 1) surface through S atom interacting with O top site. The adsorption energies and density of state indicate that SO2 interacted with the surface lattice oxygen of CeO2 to form a SO3-like species. The surface charge was redistributed during the formation of SO3, which promoted the adsorption of Hg0 on the CeO2(1 1 1) surface. H2O leaned to bond with surface Ce atoms. The inhibitive impact of H2O on Hg0 adsorption was ascribed to the following two reasons: 1) H2O competed with Hg0 for active sites; 2) H2O dissociatively adsorbed on CeO2 surface to generate Ce-OH group, and hence occupied the lattice oxygen on catalyst surface.

Silicon oxides have been recognized as a promising family of anode materials for high-energy lithium-ion batteries (LIBs) owing to their abundant reserve, low cost, environmental friendliness, easy synthesis, and high theoretical capacity. However, the extended application of silicon oxides is severely hampered by the intrinsically low conductivity, large volume change, and low initial coulombic efficiency. Significant efforts have been dedicated to tackling these challenges towards practical applications. This Review focuses on the recent advances in the synthesis and lithium storage properties of silicon oxide-based anode materials. To present the progress in a systematic manner, this review is categorized as follows: (i) SiO-based anode materials, (ii) SiO2-based anode materials, (iii) non-stoichiometric SiOx-based anode materials, and (iv) Si-O-C-based anode materials. Finally, future outlook and our personal perspectives on silicon oxide-based anode materials are presented.

Coatings are normally employed to meet some functional requirements. There is a kind of self-generated coating during use, such as the transfer layer during sliding, which may greatly affect the tribological behavior. Although the transfer layer has aroused much attention recently, the formation of the transfer layer closely depends on the service conditions, which need to be further studied. In this paper, the effects of sliding speed, normal load, and duration of wear test on the transfer layer thickness during friction of Ni/PTFE (Polytetrafluoroethylene) composites were experimentally investigated. The formation mechanism of transfer layer and the relationships between tribological properties and transfer layer thickness were analyzed in detail. It was found that the transfer layer thickness increased with increases of sliding speed and normal load, and after a period of wear test, the transfer layer thickness remained stable. The transfer layer thickness correlates linearly with the friction coefficient and wear volume of the PTFE composites. With the increase of the transfer layer thickness, the friction coefficient decreased, while the wear volume increased, which means that a uniform, thin, and stable transfer layer is beneficial for the reduction of friction and wear of the polymeric composites.

Nanostructured copper sulfide synthesized with the assistance of surfactant with nanoscale particle size and high Brunauer–Emmett–Teller surface area was for the first time applied for the capture of elemental mercury (Hg0) from coal combustion flue gas. The optimal operation temperature of nano-CuS for Hg0 adsorption is 75 °C, which indicates that injection of the sorbent between the wet flue gas desulfurization and the wet electrostatic precipitator systems is feasible. This assures that the sorbent is free of the adverse influence of nitrogen oxides. Oxygen (O2) and sulfur dioxide exerted a slight influence on Hg0 adsorption over the nano-CuS. Water vapor was shown to moderately suppress Hg0 capture efficiency via competitive adsorption. The simulated adsorption capacities of nano-CuS for Hg0 under pure nitrogen (N2), N2 + 4% O2, and simulated flue gas reached 122.40, 112.06, and 89.43 mgHg0/g nano-CuS, respectively. Compared to those of traditional commercial activated carbons and metal sulfides, the ...