Study on the influence of side-blown airflow velocities on plasma and combustion wave generated from fused silica induced by combined pulse laser

This study examines the impact of variations in side-blowing airflow velocity on plasma generation,combustion wave propagation mechanisms,and surface damage in fused silica induced by a combined millisecond-nanosecond pulsed laser.The airflow rate and pulse delay are the main experimental variables.The evolution of plasma motion was recorded using ultrafast time-resolved optical shadowing.The experimental results demonstrate that the expansion velocities of the plasma and combustion wave are influenced differently by the sideblowing airflow at different airflow rates(0.2 Ma,0.4 Ma,and 0.6 Ma).As the flow rate of the sideblow air stream increases,the initial expansion velocities of the plasma and combustion wave gradually decrease,and the side-blow air stream increasingly suppresses the plasma.It is important to note that the target vapor is always formed and ionized into plasma during the combined pulse laser action.Therefore,the side-blown airflow alone cannot completely clear the plasma.Depending on the delay conditions,the pressure of the side-blowing airflow,the influence of inverse Bremsstrahlung radiation absorption and target surface absorption mechanisms can lead to a phenomenon known as the double combustion waves when using a nanosecond pulse laser.Both simulation and experimental results are consistent,indicating the potential for further exploration of fused silica targets in the laser field.

Rapid Detection of Filoviruses by Real-time TaqMan Polymerase Chain Reaction Assays

Ebola virus （EBOV） and Marburg virus （MARV） are causative agents of severe hemorrhagic fever with high mortality rates in humans and non-human primates and there is currently no licensed vaccine or therapeutics. To date, there is no specific laboratory diagnostic test in China, while there is a national need to provide differential diagnosis during outbreaks and for instituting acceptable quarantine procedures. In this study, the TaqMan RT-PCR assays targeting the nucleoprotein genes of the Zaire Ebolavirus （ZEBOV） and MARV were developed and their sensitivities and specificities were investigated. Our results indicated that the assays were able to make reliable diagnosis over a wide range of virus copies from 103 to 109, corresponding to the threshold of a standard RNA transcript. The results showed that there were about 101 RNA copies per milliliter of virus culture supernatant, equivalent to 10,000 RNA molecules per infectious virion, suggesting the presence of many non-infectious particles. These data indicated that the TaqMan RT-PCR assays developed in this study will be suitable

Electrochemical CO_(2) mineralization for red mud treatment driven by hydrogen-cycled membrane electrolysis

CO_(2)mineralization as a promising CO_(2)mitigation strategy can employ industrial alkaline solid wastes to achieve net emission reduction of atmospheric CO_(2).The red mud is a strong alkalinity waste residue produced from the aluminum industry by the Bayer process which has the potential for the industrial CO_(2)large scale treatment.However,limited by complex components of red mud and harsh operating conditions,it is challenging to directly mineralize CO_(2)using red mud to recover carbon and sodium resources and to produce mineralized products simultaneously with high economic value efficiently.Herein,we propose a novel electrochemical CO_(2)mineralization strategy for red mud treatment driven by hydrogen-cycled membrane electrolysis,realizing mineralization of CO_(2)efficiently and recovery of carbon and sodium resources with economic value.The system utilizes H_(2)as the redox-active proton carrier to drive the cathode and anode to generate OH^(-) and H^(+) at low voltage,respectively.The H^(+) plays as a neutralizer for the alkalinity of red mud and the OH^(-) is used to mineralize CO_(2)into generate highpurity NaHCO_(3)product.We verify that the system can effectively recover carbon and sodium resources in red mud treatment process,which shows that the average electrolysis efficiency is 95.3%with highpurity(99.4%)NaHCO_(3)product obtained.The low electrolysis voltage of 0.453 V is achieved at10 mA·cm^(-2) in this system indicates a potential low energy consumption industrial process.Further,we successfully demonstrate that this process has the ability of direct efficient mineralization of flue gas CO_(2)(15%volume)without extra capturing,being a novel potential strategy for carbon neutralization.

Critical review and functional safety of a battery management system for large‑scale lithium‑ion battery pack technologies

The battery management system(BMS)is the main safeguard of a battery system for electric propulsion and machine electrifcation.It is tasked to ensure reliable and safe operation of battery cells connected to provide high currents at high voltage levels.In addition to efectively monitoring all the electrical parameters of a battery pack system,such as the voltage,current,and temperature,the BMS is also used to improve the battery performance with proper safety measures within the system.With growing acceptance of lithium-ion batteries,major industry sectors such as the automotive,renewable energy,manufacturing,construction,and even some in the mining industry have brought forward the mass transition from fossil fuel dependency to electric powered machinery and redefned the world of energy storage.Hence,the functional safety considerations,which are those relating to automatic protection,in battery management for battery pack technologies are particularly important to ensure that the overall electrical system,regardless of whether it is for electric transportation or stationary energy storage,is in accordance with high standards of safety,reliability,and quality.If the system or product fails to meet functional and other safety requirements on account of faulty design or a sequence of failure events,then the environment,people,and property could be endangered.This paper analyzed the details of BMS for electric transportation and large-scale energy storage systems,particularly in areas concerned with hazardous environment.The analysis covers the aspect of functional safety that applies to BMS and is in accordance with the relevant industrial standards.A comprehensive evaluation of the components,architecture,risk reduction techniques,and failure mode analysis applicable to BMS operation was also presented.The article further provided recommendations on safety design and performance optimization in relation to the overall BMS integration.

Forecasting solar still performance from conventional weather data variation by machine learning method

Solar stills are considered an effective method to solve the scarcity of drinkable water.However,it is still missing a way to forecast its production.Herein,it is proposed that a convenient forecasting model which just needs to input the conventional weather forecasting data.The model is established by using machine learning methods of random forest and optimized by Bayesian algorithm.The required data to train the model are obtained from daily measurements lasting9 months.To validate the accuracy model,the determination coefficients of two types of solar stills are calculated as 0.935and 0.929,respectively,which are much higher than the value of both multiple linear regression(0.767)and the traditional models(0.829 and 0.847).Moreover,by applying the model,we predicted the freshwater production of four cities in China.The predicted production is approved to be reliable by a high value of correlation(0.868)between the predicted production and the solar insolation.With the help of the forecasting model,it would greatly promote the global application of solar stills.

Are more charging piles imperative to future electrified transportation system?

Scholars and practitioners believe that the large-scale deployment of charging piles is imperative to our future electric transportation systems.Major economies ambitiously install charging pile networks,with massive construction spending,maintenance costs,and urban space occupation.However,recent developments in technology may significantly reduce the necessary charging capacity required by the system.This paper develops a linear programming model to characterize the effects of likely scenarios where vehicle-to-vehicle(V2V)charging is available via vehicle modularization or wireless charging.Specifically,we consider scenarios in which vehicles can transmit energy to each other(coordinated by a central platform)while traveling closely on the same road.We first estimate the number of charging piles needed for completing the travel plan of 73 cars from data,assuming a battery capacity of 400 km’s range and no V2V charging.Our results show that once V2V charging technologies with an efficiency of 50%are available,more than 2/3 of the charging piles investment would be wasted.Additionally,if the efficiency of V2V charging increases to 75%,we can easily reduce the battery capacity of vehicles to 200 km,which will reduce production costs and improve energy efficiency.These results may reveal us an alternative pathway towards transportation electrification.

Room-temperature ferromagnetism and half-metallicity in monolayer orthorhombic CrS_(2)

Two-dimensional materials with high-temperature ferromagnetism and half-metallicity have the latest applications in spintronic devices.Based on first-principles calculations,we have investigated a novel two-dimensional CrS_(2) phase with an orthorhombic lattice.Our results suggest that it is stable in dynamics,thermodynamics,and mechanics.The ground state of monolayer orthorhombic CrS_(2) is both ferromagnetic and half-metallic,with a high Curie temperature of 895 K and a large spin-flipping gap on values of 0.804 eV.This room-temperature ferromagnetism and halfmetallicity can maintain stability against a strong biaxial strain ranging from–5%to 5%.Meanwhile,increasing strain can significantly maintain the out-of-plane magnetic anisotropy.A density of states analysis,together with the orbital-resolved magnetic anisotropy energy,has revealed that the strain-enhanced MAE is highly related to the 3d-orbital splitting of Cr atoms.Our results suggest the monolayer orthorhombic CrS_(2) is an ideal candidate for future spintronics.

Numerical simulation of the effect of coaxial and cross-axis injection modes on pulverized coal combustion in the raceway of blast furnace tuyere

The aim of this study is to investigate the influence of the angle of the pulverized coal (PC) injection lance on the combustion characteristics of fuel in the raceway of blast furnace tuyeres. Using FLUENT software, a Euler-Lagrange three-dimensional numerical model was constructed to analyze the influence of different positions of blast furnace tuyere coal powder injection lance (coaxial and cross-axis) on key parameters such as temperature distribution, gas flow, and combustion efficiency. The results demonstrate that adjusting the angle of the injection lance significantly modifies the average and peak temperatures in the raceway, while the composition of gas components remains relatively stable. When the injection lance angle is 10°, the average temperature and peak temperature in the raceway are 2294 K and 2747 K, respectively. When the injection lance angle is 12°, the combustion efficiency of the PC reaches 80.8%. This study reveals the significant impact of the injection lance angle on the combustion process. Especially at an angle of 12°, the combustion efficiency of the blast furnace significantly improves. With coaxial injection, the combustion rate increases as the distance between the injection lance tip and the tuyere increases. This paper is instructive for the optimization of the blast furnace combustion system, which improve fuel utilization efficiency and reduce environmental emissions. This paper provides practical recommendations for adjusting blast furnace operational parameters, offering insights for achieving more efficient and environmentally friendly industrial production.

New perspectives on the genetic structure of dotted gizzard shad(Konosirus punctatus)based on RAD-seq

To maintain,develop and rationally utilize marine organisms,understanding their genetic structure and habitat adaptation pattern is necessary.Konosirus punctatus,which is a commercial fish species inhabiting the Indo-west Pacific Ocean,has shown an obvious annual global capture and aquaculture production decline due to climate changes and human activities.In the present study,restriction-site associated DNA sequencing(RAD-seq)was used to describe its genome-wide single nucleotide polymorphisms panel(SNPs).Among 146 individuals collected at nine locations scattered in China,Korea and Japan,a set of 632,090 SNPs were identified.Population genetic analysis showed that K.punctatus individuals were divided into two significant genetic clusters.Meanwhile,potential genetic differentiation between northern and southern population of K.punctatus was found.Treemix results indicated that gene flow existed among sampling locations of K.punctatus,especially from southern Japan to others.Moreover,candidate genes associated with habitat adaptations of K.punctatus were identified,which are involved in diverse physiological processes of K.punctatus including growth and development(e.g.,KIDINS220,PAN3),substance metabolism(e.g.,PGM5)and immune response(e.g.,VAV3,CCT7,HSPA12B).Our findings may aid in understanding the possible mechanisms for the population genetic structure and local adaptation of K.punctatus,which is beneficial to establish the management and conservation units of K.punctatus,guiding the rational use of resources,with reference significance for a profound understanding of the adaptative mechanisms of other marine organisms to the environment.

Toward a personalized autonomous transportation system:Vision,challenges,and solutions

The fragmented design of intelligent transportation systems creates isolated intelligent systems.Resource competition and information gaps are fierce and widespread,worsening traffic issues and degrading overall service levels.Therefore,empowered by advanced technologies,an evolution toward an autonomous transportation system(ATS)is observed.This evolution aims to develop a collaborative and sustainable ecosystem,prompting interoperability within the cloud-edge-device continuum.

CHAINS:CHAIN-based fusion safety system framework for intelligent connected vehicle

Intelligent connected vehicles,as the focus of the global automotive industry,are currently at a critical stage of large-scale commercialization.However,during the development process of vehicles from mechanical systems with limited functions to mobile intelligence with complex and multiple functions,the issues of functional safety,cybersecurity,and safety of the intended functionality are the main challenges of the industrialization of intelligent connected vehicles,including multiple safety risks such as hardware and software failures,insufficient performance in edge scenarios,cyber-attacks and data leakage.In this paper,the safety and security issues of intelligent connected vehicles,the challenges posed by emerging technology applications,and related solutions are systematically reviewed and summarized.A fusion safety system framework with the safety cube as the core of protection and control is proposed innovatively based on a field-vehicle-human safety interactional model,realizing stereoscopic,deep,and comprehensive safety protection through end-cloud collaboration.Meanwhile,an X-shaped fusion safety development process based on CHAIN is proposed.Through the empowerment of digital twin and AI technologies,it could approach interaction between physical entities and digital twin models and the automation of the development process,thereby satisfying the demands of fusion safety system design,intelligent development,rapid delivery,and continuous iteration.The fusion safety system framework and X-shaped development process proposed in this paper can provide important insight into intelligent transportation vehicles and systems'safety and security design and development.

N6-Methyladenine DNA Methylation in Japonica and Indica Rice Genomes and Its Association with Gene Expression,Plant Development, and Stress Responses

N6-Methyladenine (6mA)DNA methylation has recently been implicated as a potential new epigenetic marker in eukaryotes,including the dioot modelArabidopsis thaliana.However,the conservation and divergence of 6mA distribution patterns and functions in plants remain elusive.Here we report high-quality 6mA methylomes at single-nucleotide resolution in rice based on substantially improved genome sequences of two rice cultivars,Nipponbare (Nip;Japonica)and 93-11 (Indica).Analysis of 6mA genomic distribution and its association with transcription suggest that 6mA distribution and function is rather conserved between rice and Arabidopsis.We found that 6mA levels are positively correlated with the expression of key stressrelated genes,which may be responsible for the difference in stress tolerance between Nip and 93-11. Moreover,we showed that mutations in DDM1 cause defects in plant growth and decreased 6mA level. Our results reveal that 6mA is a conserved DNA modification that is positively associated with gene expression and contributes to key agronomic traits in plants.

Advances in critical technologies for hypersonic and high-enthalpy wind tunnel

Hypersonic and high-enthalpy wind tunnels and their measurement techniques are the cornerstone of the hypersonic flight era that is a dream for human beings to fly faster,higher and further.The great progress has been achieved during the recent years and their critical technologies are still in an urgent need for further development.There are at least four kinds of hypersonic and high-enthalpy wind tunnels that are widely applied over the world and can be classified according to their operation modes.These wind tunnels are named as air-directly-heated hypersonic wind tunnel,light-gas-heated shock tunnel,free-piston-driven shock tunnel and detonation-driven shock tunnel,respectively.The critical technologies for developing the wind tunnels are introduced in this paper,and their merits and weakness are discussed based on wind tunnel performance evaluation.Measurement techniques especially developed for high-enthalpy flows are a part of the hypersonic wind tunnel technology because the flow is a chemically reacting gas motion and its diagnosis needs specially designed instruments.Three kinds of the measurement techniques considered to be of primary importance are introduced here,including the heat flux sensor,the aerodynamic balance,and optical diagnosis techniques.The techniques are developed usually for conventional wind tunnels,but further improved for hypersonic and high-enthalpy tunnels.The hypersonic ground test facilities have provided us with most of valuable experimental data on high-enthalpy flows and will play a more important role in hypersonic research area in the future.Therefore,several prospects for developing hypersonic and high-enthalpy wind tunnels are presented from our point of view.

Observation of hydrocarbon generation and migration of highly-matured carbonates by means of laser-induced fluorescence microscopy

Some important information on hydrocarbon generation, inclusion and migration inhighly-matured carbonates of lower Palaeozoic age from the Ordos Basin and Tarim Basin has been analyzed by a newly-combined laser-induced fluorescence microscope (LFM) designed by our laboratory. The following information has been obtained from the lower Ordovician lamellar carbonates with equivalent vitrinite reflectance (Ro) as high as 1.6%-1.7% and residual TOC of 0.14%-0.35% from the Ordos Basin: wide occurrences of oil and source macerals with strong fluorescence, including G.Prisca alginite, lamalginite, telalginite and algae-detrinite; fluorescing asphalt among mineral crystals; some groundmass and spheroid-like reservoir bitumen with high maturation levels in the pores of dolomites. Various kinds of fluorescing organic inclusions and asphalt have been found in the carbonates, calcareous shales and silt-shales with high maturation levels from the Cambrian-Ordovician strata in the Tarim Basin. All this helps us find

Trimetallic oxyhydroxides as active sites for large-current-density alkaline oxygen evolution and overall water splitting

Earth-abundant electrocatalysts for large-current-density water splitting under alkaline condition are desirable.Oxygen evolution reaction,which is a bottleneck of the overall water splitting,faces the problems of complicated reconstruction and deficiency in rational design of active sites.Herein,we report a series of transition metal chalcogenides for alkaline OER.Among them,FeCoNi(S)displayed a low overpotential of 293 m V to deliver a current density of 500 m A cm^(-2),which is in the top level of non-precious metal based OER electrocatalysts.A combination of(ex)in situ characterizations and DFT calculation shows that Ni(Fe,Co)trimetallic oxyhydroxides were the active sites for highly-efficient OER.Furthermore,for FeCoNi(S),when used as a bifunctional catalyst for water splitting,it only required a cell voltage of 1.84 V to deliver~500 m A cm^(-2) with extraordinary long-term stability over 2000 h.This work provides the comprehension of high-efficiency,robust catalysts for OER and overall water splitting at large current densities in alkaline media.

High-speed unsteady flows past two-body configurations

This paper presents a detailed investigation of unsteady supersonic flows around a typical two-body configuration, which consists of a capsule and a canopy. The cases with different trailing distances between the capsule and canopy are simulated. The objective of this study is to examine the detailed effects of trailing distance on the flow fields and analyze the flow physics of the different flow modes around the parachute-like two-body model. The computational results show unsteady pulsating flow fields in the small trailing distance cases and are in reasonable agree- ment with the experimental data. As the trailing distance increases, this unsteady flow mode takes different forms along with the wake/shock and shock/shock interactions, and then gradually fades away and transits to oscillate mode, which is very different from the former. As the trailing distance keeps increasing, only the capsule wake/canopy shock interaction is present in the flow field around the two-body model, which reveals that the unsteady capsule shock/canopy shock interaction is a key mechanism for the pulsation mode.

Powered-descent landing GNC system design and flight results for Tianwen-1 mission

The powered-descent landing(PDL)phase of the Tianwen-1 mission began with composite backshell–parachute(CBP)separation and ended with landing-rover touchdown.The main tasks of this phase were to reduce the velocity of the lander,perform the avoidance maneuver,and guarantee a soft touchdown.The PDL phase overcame many challenges:performing the divert maneuver to avoid collision with the CBP while simultaneously avoiding large-scale hazards;slowing the descent from approximately 95 to 0 m/s;performing the precise hazard-avoidance maneuver;and placing the lander gently and safely on the surface of Mars.The architecture and algorithms of the guidance,navigation,and control system for the PDL phase were designed;its execution resulted in Tianwen-1’s successful touchdown in the morning of 15 May 2021.Consequently,the Tianwen-1 mission achieved a historic autonomous landing with simultaneous hazard and CBP avoidance.

PdSe_(2)/MoSe_(2) vertical heterojunction for self-powered photodetector with high performance

Van der Waals’two-dimensional(2D)material heterostructure engineering offers an effective strategy for the design of multifunctional and high-performance optoelectronic devices.However,2D heterostructure photodetectors with a photoconductive effect tend to suffer from high driving source-drain voltages and significant dark noise currents.Herein,a self-powered photodetector with high performance was fabricated based on vertically stacked graphene/MoSe_(2)/PdSe_(2)/graphene heterojunctions through a dry transfer method.The fabricated device displays current rectification characteristics in darkness(on/off ratio>10^(3))and superior photovoltaic behaviors under illumination.In addition,benefitting from the strong built-in field,the Gr/PdSe_(2)/MoSe_(2)/Gr heterojunction photodetector is able to respond to a broad spectrum from visible to near-infrared(NIR)with a remarkable responsivity of 651 mA·W^(−1),a high specific detectivity of 5.29×10^(11) Jones and a fast response speed of 41.7/62.5μs.Moreover,an enhanced responsivity of 1.16 A·W^(−1) has been obtained by a reverse voltage(−1 V)and further evaluation on image recognition has also demonstrated the great application potential of the Gr/MoSe_(2)/PdSe_(2)/Gr heterojunction photodetector.The findings are expected to bring new opportunities for the development of highly sensitive,high-speed and energy-efficient photodetectors for comprehensive applications.

Swarm Intelligence Algorithm Inspired by Route Choice Behavior

Travelers＇ route choice behavior, a dynamical learning process based on their own experience, traffic information, and influence of others, is a type of cooperation optimization and a constant day-to-day evolutionary process. Travelers adjust their route choices to choose the best route, minimizing travel time and distance, or maximizing expressway use. Because route choice behavior is based on human beings, the most intelligent animals in the world, this swarm behavior is expected to in- corporate more intelligence. Unlike existing research in route choice behavior, the influence of other travelers is considered for updating route choices on account of the reality, which makes the route choice behavior from individual to swarm. Anew swarm intelligence algorithm inspired by travelers＇ route choice behavior for solving mathematical optimization problems is introduced in this paper. A comparison of the results of experiments with those of the classical global Particle Swarm Optimization （PSO） algorithm demonstrates the efficacy of the Route Choice Behavior Algorithm （RCBA）. The novel algorithm provides a new approach to solving complex problems and new avenues for the study of route choice behavior.

Observation of double indirect interlayer exciton in MoSe_(2)/WSe_(2) heterostructure

Interlayer excitons(IXS)are electron–hole pairs bound in the spatial separation layer by the Coulomb effect,and their lifetime is several orders of magnitude longer than that of direct excitons,providing an essential platform for long-lived exciton devices.The recent emergence of the van der Waals heterostructure(HS),which combines two layers of different transitional metal dichalcogenides(TMDs),has created new opportunities for IX research.Herein,we demonstrate the observation of double indirect interlayer excitons in the MoSe_(2)/WSe_(2)HS using photoluminescence(PL)spectroscopy.The intensities of the two peaks are essentially the same,and the energy difference is 22 meV,which is perfectly in line with the calculation result of density functional theory.Furthermore,the experience of variable excitation power also proves that the splitting of the IXs originates from the conduction band spin-splitting of MoSe_(2).The observation results provide a promising platform for further exploring the new physical properties and optoelectronic phenomena of TMD HS.