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In recent years, transfer learning has been widely applied in fault diagnosis for solving the problem of inconsistent distribution of the original training dataset and the online-collecting testing dataset. In particular, the domain adaptation method can solve the problem of the unlabeled testing dataset in transfer learning. Moreover, Convolutional Neural Network (CNN) is the most widely used network among existing domain adaptation approaches due to its powerful feature extraction capability. However, network designing is too empirical, and there is no network designing principle from the frequency domain. In this paper, we propose a unified convolutional neural network architecture from a frequency domain perspective for a domain adaptation named Frequency-domain Fusing Convolutional Neural Network (FFCNN). The method of FFCNN contains two parts, frequency-domain fusing layer and feature extractor. The frequency-domain fusing layer uses convolution operations to filter signals at different frequency bands and combines them into new input signals. These signals are input to the feature extractor to extract features and make domain adaptation. We apply FFCNN for three domain adaptation methods, and the diagnosis accuracy is improved compared to the typical CNN.

To address the bottlenecks of sluggish sodium-ion transfer processes, the electrode materials of sodium-ion battery (SIB) are always designed from the viewpoints of sodium-ion diffusion kinetics or reaction thermodynamics for high-performance sodium storage. Herein, starting with spongiform TiO2/C composite derived from zinc alginate, a NH4Cl-assisted annealing strategy is developed to prepare chlorine-doped spongiform TiO2/C composite (ZATC-Cl). Acting as the anode of SIBs, the obtained ZATC-Cl delivers excellent sodium storage performance with a high reversible capacity of 352.4 mAh g−1 at 50 mA g−1, a superior rate capability of 246.8 mAh g−1 at 2 A g−1 and a considerable high-rate cycling performance of 248.5 mAh g−1 at 2 A g−1 for 1000 cycles. It is believed that the unique spongiform structure and ultra-small sized TiO2 particles in ZATC-Cl can achieve fast sodium-ion insertion/extraction, realizing rapid sodium-ion diffusion kinetics. Moreover, as well evidenced by experiment results and theoretical calculations, the Cl dopants introduced in ZATC-Cl can provide more active sites for robust sodium-ion chemical adsorption, optimizing sodium-ion reaction thermodynamics. This study demonstrates an alternative approach to improve the sodium storage capability of TiO2 anodes by the synergistically engineering the morphological and structural properties and manipulating the surface active sites, from both kinetic and thermodynamic viewpoints of sodium storage processes.

The authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (nos. 51961165103 and 51672210) and the National Key Research and Development Program of China (2018YFB1502003 and 2017YFE0193900). S.S. is supported by the National Program for Support of Top-notch Young Professionals and “The Youth Innovation Team of Shaanxi Universities.”

In this study, we examined the roles of visual and olfactory responses during foraging and courtship of the butterfly Papilio xuthus. Our results showed that P. xuthus was sensitive to color in the range of 350–500 nm. Visits of P. xuthus females and males to blue, purple, and red artificial cloth flowers were ♀ 54.90% and ♂ 39.22%, ♀ 19.61% and ♂ 35.29%, and ♀ 9.80% and ♂ 19.61%, respectively. Application of 10% honey on these artificial flowers resulted in an increase of 3.41 and 3.26 fold in flower visits by the butterfly in comparison with controls. When 10% honey water was sprayed on colorless artificial flowers, flower visits reduced seven fold for females and two fold for males, indicating that both visual and olfactory perceptions play important roles during foraging. During courtship, four types of chasing were observed in a natural population of P. Xuthus. The four types are males chasing females (49%), males chasing males (25%), females chasing males (13%), and females chasing females (10%). However, when odorless artificial mimics of butterflies were used, no significant differences were observed among these types of chasing, indicating that olfactory perception was crucial for the butterfly during courtship. Profiling volatile organic chemicals and individual bioassays revealed that α-farnesene might play an important role in distinguishing males from females during courtship of the butterfly.

Electrocatalytic conversion of carbon dioxide (CO

This paper presents different families of transfers from Low Lunar Orbit to Distant Retrograde Orbits in the Earth-Moon system and analyzes their characteristics from the perspective of velocity increment requirement, transfer time, and sensitivity to small perturbations. Initially, families of transfer trajectories in the Circular Restricted Three-Body Problem are found by the predictor-corrector method and numerical continuation. Each transfer uses two impulsive maneuvers. These families are computed for different parking orbit altitudes, constants of motion, and insertion points. Then, to investigate the sensitivity characteristics of each family, a metric based on Local Lyapunov Exponent is introduced and computed along each trajectory. This work provides various choices for future cargo and human-crewed missions in the cislunar space.

A novel strategy has been proposed to produce in situ Li

AbstractThe gravity field of Callisto can be inferred using radio tracking data from a low-altitude orbiter around the icy moon. Orbit possibilities around Callisto are currently under study for the Gan De mission proposal [2]. However, gravity field recovery using Doppler observations is highly dependent on the orbit geometry. In this study, we will show the effect of different orbit constraints on the recoverability of Callisto’s gravity field parameters.1. IntroductionThe exploration of Callisto is part of the extensive interest in the icy moons characterization. In comparison to the other Galilean moons, Callisto has kept the best-preserved records of the Jovian system formation. As other missions will focus on Ganymede and Europa, mission proposals devoted to the exploration and characterization of Callisto are currently emerging [2][6].The Gan De mission [2] is at a very early planning stage. Led by the National Space Science Center (NSSC), Chinese Academy of Science (CAS), this mission aims to send an orbiter around Callisto in order to characterize its surface and interior. Its degree of differentiation will also be investigated as well as the possible existence of an internal ocean, as Galileo measurements suggested.As part of a global characterization of Callisto, the recovery of gravity field parameters is highly dependent on the orbital characteristics of the mission. In this presentation, we will analyze the impact of the orbit choice for an orbiter around Callisto.2. Exploring different orbitsMultiple flybys of Callisto are expected from the JUICE and the Europa Clipper missions [5]. Even if this will provide additional information on Callisto, the global mapping of the outermost Galilean moon will be uniquely improved by means of an orbiter from a high inclination and a low altitude. A specific difficulty in the orbit design in the Jovian system is related to the orbit stability, which is highly impacted by the influence of Jupiter as a third body exerting strong perturbations on a Callisto orbiter Another constraint is to maximize the illumination by the Sun for solar power, which is of importance especially for low-altitude probes in the outer solar system. These constraints will all have direct implications on the orbit parameters.In this presentation, we will select a number of different low Callisto orbits for Gan De, respecting different of the above mentioned constraints, and analyze and compare their scientific value for gravity field recovery. We will explore different altitudes, Sun beta angles, Earth beta angles and mission durations. We will also analyze the possibility to use repetitive ground track orbits [3].3. Gravity field recovery simulationUsing an extended force model, different reference orbits will be propagated in the planetary extension of the Bernese GNSS Software (BSW) [4]. Today, our knowledge of Callisto’s gravity field is restricted to the results of the Galileo mission, which provided resulting its coefficients up to degree 2 coefficients [1]. In this presentation we will make use of a synthetic gravity field as ground truth for our simulation. Realistic Doppler tracking data (2-way X-band Doppler range rate) will be simulated as measurements from the Deep Space Network. These observations will then be used to reconstruct the orbit along with dynamical parameters. The focus of this presentation is on the quality of the retrieved gravity field parameters and tidal Love number k2.Within this closed loop simulation, we will investigate the effect of the orbit geometry on the gravity field recovery. The effect of realistic tracking station schedule will also be considered, and an appropriate level of white noise will be added to synthetic Doppler observations.AcknowledgementsThis study has been funded with the support of the Swiss National Foundation (SNF).References[1] Anderson, J. D., et al. "Shape, mean radius, gravity field, and interior structure of Callisto." Icarus 153.1 (2001): 157-161.[2] Blanc, M. et al: Gan De: Science Objectives and Mission Scenarios for China’s Mission to the Jupiter System, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-20179.[3] Cinelli, Marco, Christian Circi, and Emiliano Ortore. "Polynomial equations for science orbits around Europa." Celestial Mechanics and Dynamical Astronomy 122.3 (2015): 199-212.[4] Dach, R. et al. "Bernese GNSS software version 5.2." (2015).[5] Parisi, M. et al: "The gravity fields of Ganymede, Callisto and Europa: How well can JUICE do." Geophys. Res. Abstr. EGU2014 11758 (2014).[6] Smith, D. E., et al. "MAGIC, A Discovery Proposal to the Icy Moon Callisto." AGUFM 2019 (2019): P34C-03.

NiFe layer double metal hydroxide nanosheets (NiFe LDHs) have been extensively investigated as one of the best promising candidates to construct efficient bifunctional catalysts. In this research, element (vanadium) doping into NiFe LDHs grown in nickel foam were synthesized by the one-step method and applied in overall water splitting. The content and structure of the composites were adjusted to regulate the catalyst's electronic structure and reduce the onset potential and achieved unprecedented electrocatalysis for OER and HER. The V-NiFe-LDH/NF showed perfect OER and HER activities with low Tafel slopes of 31.3 and 89.8 mV dec-1, and small overpotentials of 195 and 120 mV at 10 mA cm-2 in 1.0 m KOH solution, respectively. Electrochemical analysis indicated that the efficient catalytic activity of V-NiFe-LDHs/NF mainly benefited from V doping, which optimized the electronic structure and produce defects, thereby resulting in an enhanced conductivity, facile electron transfer, and adequate active sites.

In the rapid cycling synchrotron of the China Spallation Neutron Source, the anti-correlated painting was adopted for the design scheme of the injection system. In the beam commissioning, with the optimization of the anti-correlated painting,the injection beam loss has been well controlled and the injection efficiency has exceeded 99%. Combined with other aspects of adjustments, the beam power on the target has reached 50 kW smoothly. In this paper, we have studied the injection optimization in the beam commissioning. Compared to the simulation results of the design scheme, the transverse beam distribution, transverse coupling effect and beam loss of the anti-correlated painting in the beam commissioning are somewhat different. Through the machine studies, we have carefully analyzed these differences and studied their reasons., 21 pages, 18 figures, submitted to Nucl. Instrum. Methods Phys. Res. A

Organic quinone molecules are attractive electrochemical energy storage devices because of their high abundance, multielectron reactions, and structural diversity compared with transition metal-oxide electrode materials. However, they have problems like poor cycle stability and low rate performance on account of the inherent low conductivity and high solubility in the electrolyte. Solving these two key problems at the same time can be challenging. Herein, we demonstrate that using a nitrogen-doped hierarchical porous carbon (NC) with mixed microporous/low-range mesoporous can greatly alleviate the shuttle effect caused by the dissolution of organic molecules in the electrolyte through physical binding and chemisorption, thereby improving the electrochemical performances. Lithium-ion batteries based on the anthraquinone (AQ) electrode exhibit dramatic capacity decay (5.7% capacity retention at 0.2 C after 1000 cycles) and poor rate performance (14.2 mA h g-1 at 2 C). However, the lithium-ion battery based on the NC@AQ cathode shows excellent cycle stability (60.5% capacity retention at 0.2 C after 1000 cycles, 82.8% capacity retention at 0.5 C after 1000 cycles), superior rate capability (152.9 mA h g-1 at 2 C), and outstanding energy efficiency (98% at 0.2 C). Our work offers a new approach to realize the next-generation organic batteries for long life and high rate performance.

We report the anharmonic effect of the Raman-scattering spectrum in the low-carrier density superconductor Sr

Each type of asteroids and comets are important, serving as the unique puzzle pieces of the solar system. The countless number of small bodies spread vastly from the near-Earth orbits to the main belt and beyond Jupiter. Thus, in order to complete the whole puzzle, and hence requires a well-designed roadmap of sample return (SR) missions and international coordination. The main consideration is the accreting locations of various types of asteroids, which may be referred through their redox status and abundances of water and volatile components. C-complex asteroids are water and volatile-rich, likely accreted in the outer solar system. Two C-complex asteroids are being explored by Hayabusa-2 and OSIRIS-REx missions, respectively. In contrast, enstatite chondrite-like asteroids formed under extremely reducing conditions in the inner solar system. The samples returned from enstatite chondrite-like asteroids will clarify the nebular processes in the zone closest to the Sun, and reveal fractionation of the solar nebula along the radial direction, via comparing with those of the C-complex asteroids. The exploration will also shed light on the bulk compositions of the Earth and terrestrial planets accreted in the same region of the inner solar system. The SR missions will focus on the first 10 Ma history of the solar system, including the initial condition, the nebular processes, and the accretion of planetesimals. Because the secondary processes that took place in planetesimals, such as thermal metamorphism, aqueous alteration, melting and differentiation, could largely erase the records of the nebular events, it is critically important to choose the primordial asteroid targets. Although C-complex asteroids accreted at low temperature in the outer solar nebula, they, especially those hydrated, could have suffered severe aqueous alteration as observed in CM chondrites. Other preferred targets are L-type asteroids, which probably contain abundant Ca-, Al-rich inclusions, the first solid assemblages of the solar system. Based on the roadmap of SR missions, we propose to return samples first from enstatite chondrite-like or L-type Near-Earth asteroids.

To answer key scientific questions about Planetary Systems, it is particularly fruitful to study the Jupiter System, the most complex “secondary” planetary system in the solar system, using the power of in situ exploration. Two key questions should be addressed by future missions:A-How did the Jupiter System form? Answers can be found in the most primitive objects of the system: Callisto seems to have been only partly differentiated; its bulk composition, interior and surface terrains keep records of its early eons; the 77 or so irregular satellites, wandering far out beyond the region occupied by the Galilean satellites, are unique and precious remnants of the populations of planetesimals which orbited the outer Solar System at the time of Jupiter’s formation.B-How does it work? One can address this question by studying and understanding the chain of energy transfer operating today in the Jupiter System: how is gravitational energy from Jupiter transferred to Io’s interior via tidal heat dissipation to power its volcanic activity? How does this activity in turn store energy into the Io plasma torus to drive the whole magnetosphere into motion? How does the interplay between the Io torus and the solar wind dump energy into heating of Jupiter’s upper atmosphere, or release it into the tail and interplanetary space?Starting from the measurement requirements derived from these two objectives, we propose two ambitious mission scenarios, named JCO and JSO, to meet these requirements. Both use the combination of a main spacecraft and one or several specialized small platforms.JCO, the Jupiter Callisto Orbiter, first flies by and characterizes several irregular satellites during its Jovian orbital tour. It is then injected into Callisto orbit to characterize its surface and interior, investigate its degree of differentiation and search for the possible existence of an internal ocean. As an option, JCO could release a lander to Callisto’s surface to perform key measurements of chemical composition, clues to understanding the formation scenario of the Galilean moons.JSO, the Jupiter System Observer, performs several fly-bys of Io and visits several irregular satellites during its Jovian orbital tour. As an option, JSO could release one or several small satellites to perform multi-point studies of the dynamics of the Jovian magnetosphere. At the end of its tour it could be injected into a halo orbit around the L1 Lagrangian point of the Sun-Jupiter system to monitor the solar wind upstream of the Jovian magnetosphere, measure Jovian seismic oscillations, and perform a comprehensive survey of the irregular satellites.Led by China under the name of GAN De, the first astronomer to have claimed an observation of a moon of Jupiter four centuries BC, and broadly open to international collaboration, a mission flying to Jupiter in the 2030’s according to either one of these scenarios will be able to capitalize on the legacy of previous missions to Jupiter (Juno, JUICE, Europa Clipper) and to trigger a very exciting international collaboration to unravel the mysteries of the origins and workings of the Jupiter system.

BACKGROUND Brucella is a gram-negative, nonmotile bacterium without a capsule. The infection scope of Brucella is wide. The major source of infection is mammals such as cattle, sheep, goats, pigs, and dogs. Currently, human beings do not transmit Brucella to each other. When humans eat Brucella-contaminated food or contact animals or animal secretions and excretions infected with Brucella, they may develop brucellosis. Although brucellosis does not originate in humans, its diagnosis and cure are very difficult; thus, it has a huge impact on humans. Even with the rapid development of medical science, brucellosis is still a major problem for Chinese people. Currently, the number of patients with brucellosis in China is 100,000 per year. In addition, due to the ongoing improvement in the living standards of Chinese people, the demand for meat products has gradually increased, and increased meat transactions have greatly promoted the spread of brucellosis. Therefore, many researchers are concerned with investigating the transmission of Brucella as well as the diagnosis and treatment of brucellosis. Mathematical models have become an important tool for the study of infectious diseases. Mathematical models can reflect the spread of infectious diseases and be used to study the effect of different inhibition methods on infectious diseases. The effect of control measures to obtain effective suppression can provide theoretical support for the suppression of infectious diseases. Therefore, it is the objective of this study to build a suitable mathematical model for brucellosis infection. OBJECTIVE We aimed to study the optimized precontrol methods of brucellosis using a dynamic threshold–based microcomputer model and to provide critical theoretical support for the prevention and control of brucellosis. METHODS By studying the transmission characteristics of Brucella and building a Brucella transmission model, the precontrol methods were designed and presented to the key populations (Brucella-susceptible populations). We investigated the utilization of protective tools by the key populations before and after precontrol methods. RESULTS An improvement in the amount of glove-wearing was evident and significant (PP=.95). Hat-wearing among the key populations increased from 57.3% before the precontrol methods to 58.6% after the precontrol methods, an increase of 1.3%. CONCLUSIONS By demonstrating the optimized precontrol methods for a brucellosis model built on a dynamic threshold–based microcomputer model, this study provides theoretical support for the suppression of Brucella and the improved usage of protective measures by key populations.

BACKGROUND Rabies is an acute infectious disease of the central nervous system caused by the rabies virus. The mortality rate of rabies is almost 100%. For some countries with poor sanitation, the spread of rabies among dogs is very serious. OBJECTIVE The objective of this paper was to study the ecological transmission mode of rabies to make theoretical contributions to the suppression of rabies in China. METHODS A mathematical model of the transmission mode of rabies was constructed using relevant data from the literature and officially published figures in China. Using this model, we fitted the data of the number of patients with rabies and predicted the future number of patients with rabies. In addition, we studied the effectiveness of different rabies suppression measures. RESULTS The results of the study indicated that the number of people infected with rabies will rise in the first stage, and then decrease. The model forecasted that in about 10 years, the number of rabies cases will be controlled within a relatively stable range. According to the prediction results of the model reported in this paper, the number of rabies cases will eventually plateau at approximately 500 people every year. Relatively effective rabies suppression measures include controlling the birth rate of domestic and wild dogs as well as increasing the level of rabies immunity in domestic dogs. CONCLUSIONS The basic reproductive number of rabies in China is still greater than 1. That is, China currently has insufficient measures to control rabies. The research on the transmission mode of rabies and control measures in this paper can provide theoretical support for rabies control in China.

Background Rabies is an acute infectious disease of the central nervous system caused by the rabies virus. The mortality rate of rabies is almost 100%. For some countries with poor sanitation, the spread of rabies among dogs is very serious. Objective The objective of this paper was to study the ecological transmission mode of rabies to make theoretical contributions to the suppression of rabies in China. Methods A mathematical model of the transmission mode of rabies was constructed using relevant data from the literature and officially published figures in China. Using this model, we fitted the data of the number of patients with rabies and predicted the future number of patients with rabies. In addition, we studied the effectiveness of different rabies suppression measures. Results The results of the study indicated that the number of people infected with rabies will rise in the first stage, and then decrease. The model forecasted that in about 10 years, the number of rabies cases will be controlled within a relatively stable range. According to the prediction results of the model reported in this paper, the number of rabies cases will eventually plateau at approximately 500 people every year. Relatively effective rabies suppression measures include controlling the birth rate of domestic and wild dogs as well as increasing the level of rabies immunity in domestic dogs. Conclusions The basic reproductive number of rabies in China is still greater than 1. That is, China currently has insufficient measures to control rabies. The research on the transmission mode of rabies and control measures in this paper can provide theoretical support for rabies control in China.

Pesticide and veterinary drug residues in food and environment pose a threat to human health, and a rapid, super-sensitive, accurate and cost-effective analysis technique is therefore highly required to overcome the disadvantages of conventional techniques based on mass spectrometry. Recently, the surface-enhanced Raman spectroscopy (SERS) technique emerges as a potential promising analytical tool for rapid, sensitive and selective detections of environmental pollutants, mostly owing to its possible simplified sample pretreatment, gigantic detectable signal amplification and quick target analyte identification via finger-printing SERS spectra. So theoretically the SERS detection technology has inherent advantages over other competitors especially in complex environmental matrices. The progress in nanostructure SERS substrates and portable Raman appliances will promote this novel detection technology to play an important role in future rapid on-site assay. This paper reviews the advances in nanostructure-based SERS substrates, sensors and relevant portable integrated systems for environmental analysis, highlights the potential applications in the detections of synthetic chemicals such as pesticide and veterinary drug residues, and also discusses the challenges of SERS detection technique for actual environmental monitoring in the future.

BACKGROUND Mathematical models have become a very important tool for the study of infectious diseases. Mathematical models can reflect the spread of infectious diseases, and can also be used to study the effect of different inhibition methods on the suppression of infectious diseases. The effect of control measures to obtain effective suppression programs can provide theoretical support for the suppression of infectious diseases. Therefore, it is the major objective of this study to build a suitable mathematical model for Brucellosis infection. OBJECTIVE To study the optimized pre-control method of Brucellosis model by the dynamic threshold-based microcomputer model, and to provide critical theoretical support for the prevention and control of Brucellosis. METHODS By studying the transmission characteristics of Brucella and building a Brucella transmission model, a pre-control method for key populations (Brucella susceptible populations) is designed according to these characteristics, thereby exploring the utilization of protective tools by key groups before and after pre-control. RESULTS The improvement in “whether wearing gloves” is the most obvious, which increases from 51.01% before the pre-control to 66.22% after the pre-control, with an increase of 15.21%. The difference is statistically significant (P0.05). CONCLUSIONS The research results of Brucellosis have provided theoretical support for the suppression of Brucella and the protective measures for key populations.

BACKGROUND Rabies is a zoonotic acute infectious disease of the central nervous system caused by the rabies virus. Because rabies patients have outstanding clinical manifestations of being afraid to drink water, this disease is also called "water phobia". However, diseased animals do not have this characteristic. The main clinical manifestations are peculiar mania, fear of anxiety, fear of wind and water, salivation and pharyngeal muscle spasm. Eventually, paralysis will endanger life. The various lengths of the incubation period are one of the characteristics of this disease. Most cases occur within 3 months, with 4% to 10% occurring in more than half a year, and about 1% in cases exceeding 1 year. The longest case in the literature is 10 years. Factors that affect the length of the incubation period are age (shorter in children), wound site (head and facial occurring earlier), depth of wound (the deep occurring earlier), number of virus invasions, the virulence of the strain, and whether formalized debridement processing and rabies vaccine prevention are performed. Others such as trauma, cold, and overwork may contribute to early onset. The earliest country to propose the term rabies was Ancient Babylon. At that time, there was no effective rabies control method, and the pain was unbearable at the onset with a high lethal rate. Therefore, many people chose to commit suicide after being bitten by dogs. There are more than 150 countries in the world that have caused a large number of deaths due to the wild spread of rabies. At present, only one-quarter of the country can effectively control the occurrence of rabies. Especially in some countries with severe health conditions, the number of rabies cases is far ahead and difficult to control. In Asia, India is the country with the most severe rabies situation, with an annual incidence of 20,000 cases, followed by Southeast Asia and most parts of Africa. The vaccination rate of dogs in China is relatively low, especially in rural areas, free-range dogs are rarely vaccinated. Therefore, the death toll from rabies is still huge. The number of people who died of rabies in China in the past two decades has shown a trend of rising first and then falling. The number of rabies deaths rose rapidly in the 1990s, reaching a peak in 2007. After the unremitting efforts of relevant personnel in China, the number of rabies deaths has slowly decreased and has decreased by about 76% in 2013. At present, there are still a considerable number of wild dogs foraging outside in China. Garbage yards and schools are all places where wild dogs may gather. Thus, during the transmission of rabies, wild dogs are an important source of infection that cannot be ignored. In addition, wild dogs lack human domestication, and the situation that wild dogs bite humans is constantly occurring. Therefore, this paper conducts a comprehensive study of domestic dogs, wild dogs, and humans in studying the spread of rabies. OBJECTIVE This paper is to study the ecological transmission mode of rabies to make theoretical contributions to the suppression of rabies in China. METHODS A mathematical model is constructed aiming at the transmission mode of rabies. During the construction of the mathematical model, the relevant data comes from the officially published data in China and the research data of previous literature. According to this model, this study performs the fitting of the number of rabies patients and the prediction of the number of rabies patients in the future. Also, it studies the effectiveness of different rabies suppression measures. RESULTS The results of the study indicate that the number of people infected with rabies rises in the first stage, and then decreases. In about 10 years, the number of rabies cases will be controlled within a relatively stable range. According to the prediction results of the model in this paper, the number of rabies will eventually be controlled to about 500 people every year. Controlling the birth rate of domestic and wild dogs as well as increasing the level of rabies immunity in domestic dogs are relatively effective rabies suppression programs. CONCLUSIONS The basic reproductive number of rabies in China is still greater than 1 after the study in this paper. Therefore, in terms of rabies control, China still needs many studies, policy formulation, and grassroots implementation. In addition, the research on rabies transmission mode and control measures in this paper can provide theoretical support for rabies control in China.

Controversies on the surface termination of α-Fe2O3 (0001) focus on its surface stoichiometry dependence on the oxygen chemical potential. Density functional theory (DFT) calculations applying the commonly accepted Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional to a strongly correlated system predict the best matching surface termination, but would produce a delocalization error, resulting in an inappropriate bandgap, and thus are not applicable for comprehensive hematite system studies. Besides, the widely applied PBE+U scheme cannot provide evidence for existence of some of the successfully synthesized stoichiometric α-Fe2O3 (0001) surfaces. Hence, a better scheme is needed for hematite DFT studies. This work investigates whether the strongly constrained and appropriately normed (SCAN) approximation reported by Perdew et al. could provide an improved result for the as-mentioned problem, and whether SCAN can be applied to hematite systems. By comparing the results calculated with the PBE, SCAN, PBE+U, and SCAN+U schemes, we find that SCAN and SCAN+U improves the description of the electronic structure of different stoichiometric α-Fe2O3 (0001) surfaces with respect to the PBE results, and that they give a consistent prediction of the surface terminations. Besides, the bulk lattice constants and the bulk density of states are also improved with the SCAN functional. This study provides a general characterization of the α-Fe2O3 (0001) surfaces and rationalizes how the SCAN approximation improves the results of hematite surface calculations.

Akaganeite (β-FeOOH) is a widely investigated candidate for photo(electro)catalysis, such as water splitting. Nevertheless, insights into understanding the surface reaction between water and β-FeOOH, in particular, the hydrogen evolution reaction (HER), are still insufficient. Herein, a set of first-principles calculations on pristine β-FeOOH and halogen-substituted β-FeOOH are applied to evaluate the HER performance through the computational hydrogen electrode model. The results show that the HER on β-FeOOH tends to occur at Fe sites on the (010) surface, and palladium and nickel are found to serve as excellent co-catalysts to boost the HER process, due to the remarkably reduced free energy change of hydrogen adsorption upon loading on the surface of β-FeOOH, demonstrating great potential for efficient water splitting.

Asteroid impacts pose a major threat to all life on Earth. Deflecting an asteroid on an impact trajectory is critical to mitigating this threat. A kinetic impactor remains the most feasible asteroid deflection method. However, due to launch capability constraints, an impactor with a limited mass can only minimally change the velocity of an asteroid. To improve the deflection efficiency of the kinetic impactor strategy, this paper proposes the Assembled Kinetic Impactor (AKI), which combines the spacecraft with the launch vehicle upper stage. After the launch vehicle upper stage sends the spacecraft into an Earth-escaping trajectory, the spacecraft-rocket separation is not performed, and the spacecraft controls the AKI to impact the asteroid. By retaining the mass of the launch vehicle upper stage, the mass of the impactor is increased, thereby enhancing the deflection efficiency. According to the technical data of the Long March 5 (CZ-5) launch vehicle, missions to deflect Bennu are designed to demonstrate the power of the AKI concept. Simulation results of the AKI compared with the Classical Kinetic Impactor (CKI, with spacecraft-rocket separation) show that the addition of the mass of the upper stage increases the deflection distance by >3 times. To achieve a given deflection distance, the addition of the upper stage mass reduces the number of launches to 1/3 that of the number of CKI launches. The AKI concept makes it possible to deflect large Bennu-like asteroids with a nuclear-free technique with a 10-year launch lead time. Additionally, with a single CZ-5, the deflection distance of a 140-m-diameter asteroid with a 10-year launch lead time increases from less than 1 to more than 1 Earth radius, representing an improvement in the reliability and efficiency of asteroid deflection missions.

The impact of climate change on the hydrological process has been paid more attention, especially in water shortage regions. The purpose of this study was to explore the sensitivity of climate change to runoff in the Heihe river basin in China. On the basis of long-term meteorological series data, climate change sensitivity scenarios were generated by the method of arbitrary scenario setting, which were used as input data for HSPF model and climate assessment tool (CAT) simulation runoff evaluation. Results show that: (1) The HSPF model has been calibrated and validated to perform well and is considered appropriate for predicting the hydrological effects of climate change in the study area. (2) The simulated hydrological process were sensitive to climate variations, and the effect of precipitation on runoff is greater than that of temperature. The impact of precipitation increase on flow was greater than the precipitation decreases. These results will provide scientific references for watershed water resources management and planning at the basin scale.

Machine learning method has been widely applied in industrial fault diagnosis, especially the deep learning method. In the field of industrial fault diagnosis, deep learning is mostly used to extract features of vibration signals to achieve end-to-end fault diagnosis systems. Due to the complexity and variety of actual industrial datasets, some deep learning models are designed to be complicated. However, designing neural network architectures requires rich professional knowledge, experience, and a large number of experiments, increasing the difficulty of developing deep learning models. Fortunately, Neural Architecture Search (NAS), a branch of Automated Machine Learning (AutoML), is developing rapidly. Given a search space, NAS can search for networks that perform better than manually designed. In this paper, a one-shot NAS method for fault diagnosis is proposed. The one-shot model is a supernet that contains all candidate networks in a given search space. The supernet is trained to evaluate the actual performance of candidate networks by measuring the difference between its output probability and the true labels. According to the prediction of supernet, the networks with excellent performance can be searched, using some common search methods such as random search or evolutionary algorithm. Finally, the searched network is trained by reusing the weights of the supernet. To evaluate the proposed method, two search spaces are designed, ResNet and Inception search spaces, to search on PHM 2009 Data Challenge gearbox dataset. The state-of-the-art results are obtained, and accuracies of searched ResNet-A and Inception-A are 84.11% and 83.81%, which are 3.29% and 10.88% higher than Reinforcement Learning based NAS.

Decay in electrochemical performance resulting from the "shuttle effect" of dissolved lithium polysulfides is one of the biggest obstacles for the realization of practical applications of lithium-sulfur (Li-S) batteries. To meet this challenge, a 2D g-C3 N4 /graphene sheet composite (g-C3 N4 /GS) was fabricated as an interlayer for a sulfur/carbon (S/KB) cathode. It forms a laminated structure of channels to trap polysulfides by physical and chemical interactions. The thin g-C3 N4 /GS interlayer significantly suppresses diffusion of the dissolved polysulfide species (Li2 Sx ; 2

An efficient hierarchical structure, nano-branch containing anatase TiO2 nanofibers and rutile nanorods, was prepared via the combination of the electrospinning and hydrothermal processes. This novel configuration of TiO2 multiphase possessed higher surface area, roughness, and fill factors compared with each single phase component prepared in the same condition, which significantly enhanced its light absorption. Our experimental results showed that within the interface of multiphase TiO2, the heterojunction promoted the charge separation and improved the charge transfer rate, leading to higher efficiency for photoelectrochemical water splitting. The photocurrent density of the nano-branched TiO2 electrode could reach 0.95 mA/cm2, which was almost twice as large as that of the pristine TiO2 nanorod. Our work provides a simple and feasible routine to synthesize complex TiO2 nanoarchitectures, which lays a foundation for improving energy storage and conversion efficiency of TiO2-based photoelectrodes.

Sea-floor carbonate precipitates (SCPs), commonly seen in pre-Cambrian strata, were widely developed during the Permian–Triassic mass extinction and the Early Triassic recovery interval. Most SCPs are found in shallow water facies, with few SCPs reported from deep sea settings. Here, we document Lower Triassic deep sea SCPs from turbidite deposits exposed at the Xiukang section, South Tibet, China. The SCPs only occur within thin-bedded, silty limestones that are embedded in dark grey shale. Parallel–aligned mud cobbles, rounded micritic intraclasts and micro-erosional surfaces are commonly seen in these planar laminated limestones that contain abundant radiolarians and thin-shelled bivalves, indicating deposition in a deep basin via turbidity currents. The deep sea SCPs, which are comprised of bladed calcite crystals, display a weak vertical δ13C variation with the overlying matrix, and a uniform element distribution and consequently have a homogenous cathodoluminescence pattern, suggesting rapid precipitation in the open ocean, followed by a quick burial, which led to minimal diagenetic effects on the SCPs. We propose a new hypothesis that rapid carbonate precipitation resulted from mixing, driven by the turbidity current that introduced shallow seawater to the deep seawaters with a high alkalinity. Based on this model, the turbidity currents during the Early Triassic might serve as a potential role in the connection between the oxic surface oceans and the euxinic, deep oceans.

To enhance the thermal stability of ionic liquids (ILs) and increase the latent heat, the effect of functional groups for geminal dicationic ionic compounds were investigated and compared to that of monocationic ionic liquids (MILs) analogues. A series of new functionalized ionic compounds were synthesized by introducing vinyl group, cyanomethyl group, hydroxyl group, and carboxyl group to the imidazolium cation. The structures of these ionic compounds were confirmed by 1H NMR, 13C NMR and FT-IR. The thermal stability was determined by TGA; the melting temperature, heat of fusion and heat capacity were investigated by DSC for the synthetic ionic compounds. The thermal analysis results indicate that the functionalized ionic compounds show excellent thermal stability. The decomposition temperature and melting temperature can be up to 593.17 K and 484.99 K, respectively, and the latent heat can reach 64.40 KJ·mol−1. It's increased on average by 6.30%, 34.0% and 93.93%, respectively, as compared to alkyl chain ionic liquid (C2mim)Br. In addition, the heat capacity and thermal storage density of the functionalized ionic compounds are higher than those of the MILs. These superior properties are attributed to the additional hydrogen bonds and electrostatic energy in the functionalized ionic compounds.

The generation of hydrogen by photoelectrochemical (PEC) water splitting is a promising pathway to produce renewable and scalable carbon-free energy. To improve the performance of PEC cells, it is essential to understand the structural and electronic properties of the photoelectrode/electrolyte heterogeneous interfaces. By performing first-principles molecular dynamics (FPMD) simulations, we revealed the dynamic structure, such as water dissociation and adsorption and hydrogen bond network, and the band edge alignment of the TiO2/water interfaces. Mixed molecular and dissociative water adsorption is adopted at the (001)/water interface with a water dissociation percentage of ∼25% stabilized at ambient conditions, in contrast to the unstable water dissociation at the (101)/water interface. The different interfacial structures for the two surfaces lead to their distinct proton transfer processes. The calculated band edge alignment across the interfaces shows good agreement with the experimental data and exp...

The Permian-Triassic boundary (PTB) crisis caused major shortterm perturbations in ocean chemistry, as recorded by the precipitation of anachronistic carbonates. Here, we document for the first time a global dolomitization event during the Permian-Triassic transition based on Mg/(Mg + Ca) data from 22 sections with a global distribution representing shallow- to deep-marine environments. Ten of these sections show high Mg/(Mg + Ca) ratios bracketing the PTB, recording a short-term spike in dolomite formation. The dolomite consists mainly of micron-scale anhedral to subhedral crystals that are associated with abundant fossilized bacterial bodies and extracellular polymeric substances, suggesting that dolomite precipitation was induced by microbial metabolic activity. Sections showing a dolomite spike at the PTB are widely distributed geographically, but mostly encountered in mid-shelf to upper-slope settings. Because the dolomitization event coincided with a rapid expansion of oceanic anoxia and high rates of sulfate reduction, we hypothesize that it was triggered by enhanced microbial sulfate reduction within the oceanic chemocline.

The oxygen evolution reaction (OER) is the limiting process in photoelectrochemical water splitting. Bismuth vanadate (BiVO4) is a very promising photoanode material for this but suffers experimentally from poor catalytic performance for OER. Here, we theoretically explored, by means of density functional theory calculations, supporting single metal atoms (i.e., Ag, Au, Pd, and Pt) as an effective strategy to enhance the catalytic activity of BiVO4. The OER performance of different surfaces was evaluated with the intermediate adsorption energies from a thermodynamic viewpoint. The electronic structure study was employed in details to comprehend the adsorption-changing mechanism. Based on the results, several linear relationships were derived among the adsorption energies of reaction intermediates in this work, and a volcano plot was presented to unravel the theoretical activities over different BiVO4 surfaces. It was found that the metal center dominated the interaction with the intermediates and the subs...

Delafossite structures with composition ABO2 have attracted great attention for various applications owing to their adjustable electric and optical properties. However, the photocatalytic usage of ABO2 materials is still limited, owing to the various composition of chemical elements which makes it hard to be studied and fabricated. In this work, the stabilities, electronic, and optical properties of 40 kinds of Ag and Cu based delafossite ABO2 materials have been investigated to tap the potential of photocatalytic applications by performing first-principle calculations. The bulk structure of ABO2 are derived by minimizing the total energy. The electronic properties have been studied through the calculations of band structure, density of states (DOS), and work functions by using the method of GGA + U. The calculated results indicate that 4 kinds of them has superior stability, as well as appropriate electronic and optical properties for photocatalytic applications. Among them Cu3Zn2TaO6 has the highest visible light absorption coefficient, indicating its immense potential for photocatalytic applications. This work presented some based physical properties of Ag and Cu based ABO2 structures, and will promote the applications of ABO2 materials.

In this work, we demonstrate an efficient cascade multiple heterojunction organic solar cell with inverted structure. By using two donor materials, poly(3-hexylthiosphene) (P3HT) and titanyl phthalocyanine (TiOPc), as well as two acceptor materials, [6,6]-phenyl C 61 butyric acid methyl ester (PCBM) and C 60 , the cascade multiple heterojunctions of P3HT:PCBM/TiOPc:C 60 /C 60 have been constructed. Applying the optimized inverted configuration of FTO/Zinc Tin Oxide (ZTO)/C 60 (30 nm)/TiOPc:C 60 (1:1.5, 25 nm)/P3HT:PCBM (1:0.8, 100 nm)/MoO 3 (4 nm)/Ag, the considerably enhanced open circuit voltage ( V OC ) and short circuit current ( J SC ) can be harvested together, and the power conversion efficiency (PCE) is three times higher than that of the control cell with conventional structure. The significant improvements of the inverted cell are mostly due to the broadened spectral absorption and high efficient multi-interface exciton dissociation in the cascade multiple heterojunctions, indicating that the optimized cascade heterojunctions match the inverted structure well.

The progressive loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc) is one of the hallmarks of Parkinson's disease (PD). Neuroinflammation has been proposed to contributes to the progressive nature of the disease. Early growth response-1 (Egr-1), a zinc finger transcription factor, has been shown to have a crucial role in both neuronal death and the inflammatory response. However, whether and how Egr-1 is involved in the pathogenesis of PD has not been investigated. Using the subacute 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) mouse model of PD, we identified early peak induction of Egr-1 in the SNpc but not in the striatum. In situ immunofluorescent analysis showed that Egr-1 predominantly locates in the nuclei of nigral AldoC (+) astrocytes upon MPTP treatment. Genetic ablation of Egr-1 or inhibition of its transcriptional activity by Mithramycin A significantly suppresses the activation of both astrocytes and microglia, decreases proinflammatory cytokine expression, and protects dopaminergic cell bodies from degeneration in the SNpc. Taken together, these findings demonstrate that the induction of Egr-1 promotes neuroinflammation and dopaminergic cell body loss in the SNpc of MPTP-induced mouse model, suggesting an important role of astrocytic Egr-1 in neuroinflammation in PD.

A series of perovskite materials (BaMnO3−δ and Ba1−xSrxMnO3) were synthesized by a solid-state reaction method. The content of oxygen vacancy can be controlled by verifying the sintering temperature and atmosphere. Two obvious divarications between zero-field-cooling curves and field-cooling curves were observed in a high-temperature region of 250–300 K and at a low temperature of 40 K, respectively. It is found that the different oxygen vacancy contents in BaMnO3−δ cause the change of crystalline structure and variation of the divarication temperature at a high-temperature region. The factor that controls the negative magnetic susceptibility was discussed. The superexchange interaction between Mn ions can give rise to the coexistence of the ferromagnetic phase and antiferromagnetic phase in the system. We further performed the study of magnetocaloric effect in Sr-doped BaMnO3. However, the values of magnetic entropy change and refrigeration coefficient are much smaller than those of rare-earth manganites due to the weak magnetocrystalline anisotropy in Ba1−xSrxMnO3.

Currently, the cycle performance at low rate is one of the most critical factor for realizing practical applications of Li2FeSiO4/C as a cathode of the lithium-ion batteries. To meet this challenge, calcium (Ca)-doped Li2FeSiO4/C is prepared by using the sol-gel method with soluble Li, Fe, Si and Ca sources. X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy and X-ray photoelectron spectroscopy measurements are carried out to determine the crystal structures, morphologies, particle sizes and chemical valence states of the resulting products. Rietveld refinement confirms that Ca-doped Li2FeSiO4 has a monoclinic P21/n structure and that a Ca cation occupies the Fe site in the Li2FeSiO4 lattice. The grain size of Ca-doped Li2FeSiO4 is approximately 20 nm and the nanoparticles are interconnected tightly with amorphous carbon layer. As a cathode material for the lithium-ion batteries, Li2Fe0.97Ca0.03SiO4/C delivers a high discharge capacity of 186 mAh g−1 at a 0.5 C rate. Its capacity retention after the 100th cycle reaches 87%, which increases by 25 percentage points compared with Li2FeSiO4/C. The Li2Fe0.97Ca0.03SiO4/C cathode exhibits good rate performance, with corresponding discharge capacities of 170, 157, 144 and 117 mAh g−1 at 1 C, 2 C, 5 C and 10 C rates, respectively. In summary, the improvement of the electrochemical performance can be attributed to a coefficient of the strengthened crystal structure stability during Li+ deintercalation-intercalation and restrained side reactions between electrode and electrolyte.

To enhance the thermal stability of ionic liquids (ILs) and increase the latent heat, the effect of amount of hydrogen bonds for geminal dicationic ionic liquids (DILs) was investigated and compared to that of monocationic analogues. A series of geminal dicationic ionic liquids with alkyl chain or electronegativity functional groups in the imidazolium were synthesized. Thermal stability was determined by TGA; melting point, heat of fusion, and heat capacity were investigated by DSC for synthetic DILs. The effect of molecular structure on the heat of fusion was examined by changes alkyl side-chain, linkage chain, C2–H of imidazole ring, and functional groups. Hydrogen bonding in DILs was studied, in the case of C2(eim)2(Br)2, by single-crystal X-ray diffraction. The thermal analysis results indicate that functionalized geminal dicationic ionic liquids show excellent thermal stability. The decomposition temperatures of geminal dicationic ionic liquids can be up to 603.74 K, and the latent heat can reach 159...

The highly dispersed “single-atom (SA)” catalysts on oxide supports significantly alter the catalytic reaction activity and selectivity and meanwhile save the catalyst utilization. However, prepara...

Porous liquids (PLs), as a novel liquid sorbent with permanent porosity, still present challenges such as high viscosity and melting temperatures. Herein, an efficient electrostatic repulsion strategy is proposed to engineer zeolitic imidazolate frameworks (ZIFs) type III PLs employing ZIF-8-g-BPEI nanoparticle stability dispersed into BPEI. The viscosity and melting temperatures of ZIF-8-g-BPEI PLs could be tailored via control particle size, grafting polymer, and concentration of porous nanoparticles. The existence of BPEI on the surface of ZIF-8-g-BPEI facilitates the stable dispersion of ZIFs nanoparticles in BPEI via the electrostatic repulsion as well as enhances CO2 adsorption capacity of PLs. Moreover, the CO2 adsorption amount of ZIF-8-g-BPEI-30 PLs is 6.5 times high than that of neat BPEI, suggesting the permanent free volume of ZIFs is retained in their corresponding PLs. Benefiting from the branched structure of BPEI grafted onto the outer surface of ZIFs , ZIF-8-g-BPEI-10 PLs remain liquified down to -71.1 °C, together with viscosity as 1.7 Pa·s−1 at 25 °C. Therefore, the electrostatic repulsion strategy opens an effective avenue to prepare novel liquid materials and shows numerous potential applications in gas adsorption and separation.

By adopting the First-principles method based on the density functional theory (DFT), the adsorption properties of NH3 and HCl molecules intermingled in crude oil on the Fe-based crystal planes exposed on the inner surface of a duct in a crude distillation column have been conducted. Specifically, the calculated adsorption energy of NH3 and HCl reveal the most stable adsorption sites on the three planes, and the free energy at different temperatures was corrected. Furthermore, the charge density difference and the Bader charge obviously illustrate the direction of charge transfer and the valence of the atoms after adsorption. The results of projected electron density of states (PDOS), electron localization function (ELF) and the crystal orbital Hamilton population (COHP) reveal the nature of chemical bonds and the influence of specific atomic orbitals. Accordingly, the adsorption type of the two molecules on the Fe-based crystal planes is chemical adsorption. Considering the nature of the chemical bond and the multi-component environment of the distillation column, we infer that the possible causes of corrosion are coordination ions, hydrogen embrittlement and Cl− concentration.

The defect properties of Ta3N5 (1 1 0) surface are studied by first-principles calculation. We focus on the formation of three typical defects, oxygen impurity, nitrogen vacancy, and magnesium impurity and further emphasize their roles on changing the electronic structure and band edge position of the surface. Our results show that Mg is more easily doped on (1 1 0) surface in nitrogen-rich condition, in which the formation of co-defects is energetically more favorable. These co-defects can reduce the influence of single defects on the electronic structure and band edge position of the (1 1 0) surface.