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Frontiers of physics 2020年第5期15卷 77-84页

作者： Bing Zhang Department of Physics and Astronomy University of Nevada Las VegasNV 89154USA

A formula is proposed to quantitatively estimate the signal euission rate of Commumicating Extra-Terrestrial Intelligent civilizations(CETIs)in the Galaxy.I suggest that one possible type of CETI signal would be brief radio bursts similar to fast radio bursts(FRBs).A dedicated search for FRB-like artificial signals in the Galaxy for decades may pose a meaningful upper limit on the emission rate of these signals by CETIs.The Fermi-Hart paradox is answered in terms of not having enough observing times for this and other types of signals.Whether humans should send FRB like signals in the far future is briefy discissed.

关键词： fast radio bursts astrobilogy

Progress and perspective of high-voltage lithium cobalt oxide in lithium-ion batteries

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Journal of Energy Chemistry 2022年第11期31卷 283-308,I0008页

作者： Qian Wu Bing Zhang Yingying Lu State Key Laboratory of Chemical Engineering Institute of Pharmaceutical EngineeringCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou 310027ZhejiangChina ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou 311200ZhejiangChina

Lithium cobalt oxide(LiCoO_(2),LCO)dominates in 3C(computer,communication,and consumer)electronics-based batteries with the merits of extraordinary volumetric and gravimetric energy density,high-voltage plateau,and facile synthesis.Currently,the demand for lightweight and longer standby smart portable electronic products drives the development of the upper cut-off voltage of LCO-based batteries to further improve the energy density.However,several challenges,including irreversible structural transformation,surface degradation,cobalt dissolution and oxygen evolution along with detrimental side reactions with the electrolyte remain with charging to a high cut-off voltage(>4.2 V vs.Li/Li+),resulting in rapid capacity decay and safety issues.Based on the degradation mechanisms and latest advances of the high-voltage LCO,this review summarizes modification strategies in view of the LCO structure,artificial interface design and electrolytes optimization.Meanwhile,many advanced characterization and monitoring techniques utilized to clarify the structural and interfacial evolution of LCO during charge/discharge process are critically emphasized.Moreover,the perspectives in terms of integrating multiple modification strategies,applying gel and solid-state electrolytes,optimizing the recovery process and scalable production are presented.

关键词： LiCoO2 Electrode-electrolyte interface Lithium batteries Characterization techniques

Comprehensive compensation method for the influence of disturbing gravity field on long-range rocket guidance computing

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Chinese Journal of Aeronautics 2022年第3期35卷 408-418页

作者： Yansheng WU Zongqiang WANG Bing Zhang China Aerospace Science and Technology Corporation Beijing 100048China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

With the improvement of the accuracy of the inertial system,the influence of the disturbing gravity field on the accuracy of long-range rocket has become increasingly prominent.However,in actual engineering,there are problems of low accuracy and being time-consuming for disturbing gravity field compensation.In view of this,this paper proposes a set of online comprehensive solutions combining disturbing gravity reconstruction and stellar correction.According to the pre-launch binding parameters,the net function assignment method is used in the navigation system to calculate disturbing gravity in the boost phase online.In the guidance system,a closed-loop guidance online compensation method is proposed based on the state-space perturbation method for the disturbing gravity in the coast phase.At the same time,the vertical deflection can also be corrected by stellar guidance.The calculation results are simulated and verified under different circumstances.Simulation results show that the proposed online compensation algorithm has an accuracy improvement compared with the element compensation algorithm on ground.And the stellar guidance algorithm can further correct the impact deviation.The impact deviation after comprehensive compensation does not exceed 50 m,and the compensation percentage is greater than 65%.

关键词： Disturbing gravity field Long-range rocket Online compensation Stellar guidance Vertical deflection

Drivers of microbial beta-diversity in wastewater treatment plants in China

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Journal of Environmental Sciences 2022年第5期34卷 341-349页

作者： Bing Zhang Ting Yang Chenxiang Sun Xianghua Wen College of Life and Environmental Sciences Minzu University of ChinaBeijing 100081China Environmental Simulation and Pollution Control State Key Joint Laboratory School of EnvironmentTsinghua UniversityBeijing 100084China

As one of the most well-documented biogeographic patterns,the distance-decay relation-ship provides insights into the underlying mechanisms driving biodiversity distribution.Al-though wastewater treatment plants(WWTPs)are well-controlled engineered ecosystems,this pattern has been seen among microbial communities in activated sludge(AS).However,little is known about the relative importance of environmental heterogeneity and dispersal limitation in shaping AS microbial community across China;especially they are related to spatial scale and organism types.Here,we assessed the distance-decay relationship based on different spatial scales and microbial phylogenetic groups by analyzing 132 activated sludge(AS)samples across China comprising 3,379,20016S rRNA sequences.Our results in-dicated that the drivers of distance-decay pattern in China were scale-dependent.Microbial biogeographic patterns in WWTPs were mainly driven by dispersal limitation at both local and national scales.In contrast,conductivity,SRT,and pH played dominant roles in shaping AS microbial community compositions at the regional scale.Turnover rates and the drivers of beta-diversity also varied with microorganism populations.Moreover,a quantitative re-lationship between dispersal limitation ratio and AS microbial turnover rate was generated.Collectively,these results highlighted the importance of considering multiple spatial scales and micro-organism types for understanding microbial biogeography in WWTPs and pro-vided new insights into predicting variations in AS community structure in response to environmental disturbance.

关键词： Wastewater treatment plant Distance-decay pattern Scale-dependent Microbial assembly Dispersal limitation

Recent advances in hybrid water electrolysis for energy-saving hydrogen production

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Green Chemical Engineering 2023年第1期4卷 17-29页

作者： Di Li Jibing Tu Yingying Lu Bing Zhang State Key Laboratory of Chemical Engineering Institute of Pharmaceutical EngineeringCollege of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China ZJU-Hangzhou Global Scientific and Technological Innovation Center Hangzhou311215China

Electricity-driven water splitting to convert water into hydrogen(H_(2)has been widely regarded as an efficient approach for H_(2)production.Nevertheless,the energy conversion efficiency of it is greatly limited due to the disadvantage of the sluggish kinetic of oxidation evolution reaction(OER).To effectively address the issue,a novel concept of hybrid water electrolysis has been developed for energy–saving H_(2)production.This strategy aims to replace the sluggish kinetics of OER by utilizing thermodynamically favorable organics oxidation reaction to replace OER.Herein,recent advances in such water splitting system for boosting H_(2)evolution under low cell voltage are systematically summarized.Some notable progress of different organics oxidation reactions coupled with hydrogen evolution reaction(HER)are discussed in detail.To facilitate the development of hybrid water electrolysis,the major challenges and perspectives are also proposed.

关键词： Hydrogen evolution reaction Hybrid water electrolysis Electrocatalytic oxidation Organic electro-oxidation High-value products

Prediction of dissolved oxygen content changes based on two-dimensional behavior features of fish school and T-S fuzzy neural network

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Water Science and Engineering 2022年第3期15卷 210-217页

作者： Yu-jun Bao Chang-ying Ji Bing Zhang College of Engineering Nanjing Agricultural UniversityNanjing 210031China School of Electrical and Information Engineering Changzhou Institute of TechnologyChangzhou 213032China

Dissolved oxygen(DO)content is an important index of river water quality.Water quality sensors have been used in China for urban river water monitoring and DO content prediction.However,water quality sensors are expensive and difficult to maintain,and have a short operation period and difficult to maintain.This study developed a scientific and accurate method for prediction of DO content changes using fish school features.The behavioral features of the Carassius auratus fish school were described using two-dimensional fish school images.The degree of DO content decline was graded into five levels,and the corresponding numerical ranges of cluster characteristic parameters were determined by considering the opinions of ichthyologists.Finally,the variation of DO content was predicted using the characteristic parameters of the fish school and the multiple-input single-output Takagi-Sugeno fuzzy neural network.The prediction results were basically consistent with the actual variations of DO content.Therefore,it is feasible to use the behavioral features of the fish school to dynamically predict the level of DO content in water,and this method is especially suitable for prediction of sharp decline of DO content in a relatively short time.

关键词： Fish behavior Cluster feature DO Fuzzy neural network Water quality monitoring

Study on Recognition Method of Similar Weather Scenes in Terminal Area

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Computer Systems Science & Engineering 2023年第2期44卷 1171-1185页

作者： Ligang Yuan Jiazhi Jin Yan Xu Ningning zhang Bing Zhang College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing211106China School of Aerospace Transport and ManufacturingCranfield UniversityBedfordMK430ALUnited Kingdom Travelsky Technology Limited Beijing100010China College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211106China

Weather is a key factor affecting the control of air trafﬁc.Accurate recognition and classiﬁcation of similar weather scenes in the terminal area is helpful for rapid decision-making in air trafﬁcﬂow management.Current researches mostly use traditional machine learning methods to extract features of weather scenes,and clustering algorithms to divide similar scenes.Inspired by the excellent performance of deep learning in image recognition,this paper proposes a terminal area similar weather scene classiﬁcation method based on improved deep convolution embedded clustering(IDCEC),which uses the com-bination of the encoding layer and the decoding layer to reduce the dimensionality of the weather image,retaining useful information to the greatest extent,and then uses the combination of the pre-trained encoding layer and the clustering layer to train the clustering model of the similar scenes in the terminal area.Finally,term-inal area of Guangzhou Airport is selected as the research object,the method pro-posed in this article is used to classify historical weather data in similar scenes,and the performance is compared with other state-of-the-art methods.The experi-mental results show that the proposed IDCEC method can identify similar scenes more accurately based on the spatial distribution characteristics and severity of weather;at the same time,compared with the actualﬂight volume in the Guangz-hou terminal area,IDCEC's recognition results of similar weather scenes are con-sistent with the recognition of experts in theﬁeld.

关键词： Air trafﬁc terminal area similar scenes deep embedding clustering

When and How Plate Tectonics Began?

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Journal of Earth Science 2023年第4期34卷 1302-1303页

作者： Shao-Bing Zhang School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China

Plate tectonics is the most important discovery in Earth Science in the 20th Century and is the core theory of Solid Earth Science. It describes that the Earth’ s lithosphere is divided into several plates that slide on top of the asthenosphere and move relative to each other along divergent, convergent, and transform plate boundaries. From a physical point of view.

关键词： Earth divergent tectonics

Risk assessment of erosive aggressiveness due to the condensation shock by numerical simulation

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Journal of Hydrodynamics 2022年第2期34卷 200-206页

作者： Wei zhang bing Zhu Science and Technology on Water Jet Propulsion Laboratory Marine Design and Research Institute of ChinaShanghai200011China School of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai200093China

Cavitation is,for the engineering areas such as fluid machinery and ship propulsion,a known source of erosion.The erosion damage due to cavitation bubble collapse can lead to extreme failure events,implying the replacement of a ship propeller or a turbine in a hydropower plant,all of which are very costly operations.The dynamics of cavitation hydraulic structure is of great importance for cavitation erosion.As a result,the blade surface endures some extremely high stresses,which lead to the cause of wear.Two major mechanisms,re-entrant jet as well as condensation shock,are known to such transient cavitating flow.In the present work we study the latter since less has been reported for the erosion caused by such an unsteady cavitating flow.We adopted an energy transportation equation based method,combined with a collapse event detection strategy,to carry out numerical erosion risk assessment for erosive aggressiveness due to the condensation shock.Comparing with the paint test,our result shows good agreement in the erosive pattern.We further discussed the hydrodynamics of the related flow structures.

关键词： Condensation shock numerical simulation cavitation erosion

TeV emission as an independent probe of GRB jet properties

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 164-164页

作者： Bing Zhang Nevada Center for Astrophysics and Department of Physics and Astronomy University of NevadaLas Vegas NV 89154USA

In recent years,very-high-energy(VHE,>100 Ge V)emission has been detected from gamma-ray bursts(GRBs)by imaging atmospheric Cherenkov telescopes(IACTs)(e.g.,refs.[1,2]).Very recently,a huge amount of VHE photons were ... 详细信息

关键词： 1,2 e detect