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Seasonal variations of mass absorption efficiency of elemental carbon in PM_(2.5) in urban Guangzhou of South China

环境科学学报:英文版 2023年第11期133卷 83-92页

作者： Chenglei Pei Yunfei Wu Jun tao Leiming zhang tao Zhang Runqi zhang Sheng Li State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China Guangzhou Sub-branch of Guangdong Ecological and Environmental Monitoring Center Guangzhou 518049China Key Laboratory of Middle Atmosphere and Global Environment Observation Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Institute for Environmental and Climate Research Jinan UniversityGuangzhou 510632China Air Quality Research Division Science and Technology BranchEnvironment and Climate Change CanadaTorontoCanada Guangdong Ecological and Environmental Monitoring Center Guangzhou 510308China

This study investigates seasonal variations of mass absorption efficiency of elemental carbon(MAE_(EC))and possible influencing factors in urban Guangzhou of South China.Mass concentrations of elemental carbon(EC)and organic carbon(OC)in PM_(2.5) and aerosol absorption coefficient(b_(ap))at multi-wavelengths were simultaneously measured in four seasons of 2018-2019 at hourly resolution by a semi-continuous carbon analyzer and an aethalometer.Seasonal average mass concentrations of EC were in the range of 1.36-1.70μgC/m^(3) with a lower value in summer than in the other seasons,while those of OC were in the range of 4.70–6.49μgC/m^(3) with the lowest value in summer and the highest in autumn.Vehicle exhaust from local traffic was identified to be the predominant source of carbonaceous aerosols.The average aerosol absorption Angstrom exponents(AAE)were lower than 1.2 in four seasons,indicating EC and b_(ap) were closely related with vehicle exhaust.Seasonal MAE EC at 550 nm was 11.0,8.5,10.4 and 11.3 m^(2)/g in spring,summer,autumn,and winter,respectively.High MAE EC was related with the high mass ratio of non-carbonaceous aerosols to EC and high ambient relative humidity.

关键词： Vehicle exhaust Non-carbonaceous aerosols Absorption enhancement Relative humidity

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Paleoenvironment reconstruction of the Middle Ordovician thick carbonate from western Ordos Basin, China

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Petroleum Science 2023年第1期20卷 48-59页

作者： Jia-Qi Yang Jun-tao Zhang Zhi-Liang He tao Zhang School of Energy Resources China University of GeosciencesBeijing100083China SINOPEC Exploration and Production Research Institute Beijing100083China China Petrochemical Corporation Ltd. Beijing100728China

Reconstructing paleoenvironments has long been considered a vital component for understanding the development and evolution of carbonate reservoirs.The Middle Ordovician Period is considered the archetypical greenhouse interval,and also a critical period in biological evolution.The Middle Darriwilian isotope carbon excursion has been observed in many areas of the world and may be related to the biological explosions caused by decreases in the temperature.The thick carbonate rocks in the fifth member of the Middle Ordovician Majiagou Formation in the Dingbei area of the Ordos Basin were chosen as an example,based on the concentration of major,trace and rare earth elements as well as C,O and Sr isotopic analyses,the paleoenvironment was reconstructed.And its impact on natural gas exploration was analyzed.The results show that the seawater paleotemperature was 29℃,suboxicanoxic paleoredox conditions were observed,and the seawater paleosalinity was high.A large number of plankton in the biological explosion caused a rapid increase in the total organic carbon in carbonate rocks,which provided natural gas as supplemental source rocks.Affected by early meteoric water,the dissolution of gypsum laid the foundation for high-quality reservoirs,and the residual gypsum also further preserved natural gas.This study provides new data for the paleoenvironment and a theoretical basis for further natural gas exploration.

关键词： Middle darriwilian isotope carbon excursion Paleoenvironment Natural gas exploration Middle ordovician Ordos basin

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Camera,LiDAR,and IMU Based Multi-Sensor Fusion SLAM:A Survey

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Tsinghua Science and Technology 2024年第2期29卷 415-429页

作者： Jun Zhu Hongyi Li tao Zhang Department of Automation Tsinghua UniversityBeijing 100084China

In recent years,Simultaneous Localization And Mapping(SLAM)technology has prevailed in a wide range of applications,such as autonomous driving,intelligent robots,Augmented Reality(AR),and Virtual Reality(VR).Multi-sensor fusion using the most popular three types of sensors(e.g.,visual sensor,LiDAR sensor,and IMU)is becoming ubiquitous in SLAM,in part because of the complementary sensing capabilities and the inevitable shortages(e.g.,low precision and long-term drift)of the stand-alone sensor in challenging environments.In this article,we survey thoroughly the research efforts taken in this field and strive to provide a concise but complete review of the related work.Firstly,a brief introduction of the state estimator formation in SLAM is presented.Secondly,the state-of-the-art algorithms of different multi-sensor fusion algorithms are given.Then we analyze the deficiencies associated with the reviewed approaches and formulate some future research considerations.This paper can be considered as a brief guide to newcomers and a comprehensive reference for experienced researchers and engineers to explore new interesting orientations.

关键词： multi-sensor fusion Simultaneous Localization And Mapping(SLAM) navigation localization

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Coordinated response of milk bacterial and metabolic profiles to subacute ruminal acidosis in lactating dairy cows

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Journal of Animal Science and Biotechnology 2023年第6期14卷 2483-2495页

作者： Yingyu Mu Wangpan Qi tao Zhang Jiyou zhang Shengyong Mao Ruminant Nutrition and Feed Engineering Technology Research Center College of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095China Laboratory of Gastrointestinal Microbiology Jiangsu Key Laboratory of Gastrointestinal Nutrition and Animal HealthNational Center for International Research on Animal Gut NutritionCollege of Animal Science and TechnologyNanjing Agricultural UniversityNanjing 210095China

Background Bovine milk is an important source of nutrition for human consumption,and its quality is closely associated with the microbiota and metabolites in it.But there is limited knowledge about the milk microbiome and metabolome in cows with subacute ruminal acidosis.Methods Eight ruminally cannulated Holstein cows in mid lactation were selected for a 3-week experiment.The cows were randomly allocated into 2 groups,fed either a conventional diet(CON;40%concentrate;dry matter basis)or a high-concentrate diet(HC;60%concentrate;dry matter basis).Results The results showed that there was a decreased milk fat percentage in the HC group compared to the CON group.The amplicon sequencing results indicated that the alpha diversity indices were not affected by the HC feeding.At the phylum level,the milk bacteria were dominated by Proteobacteria,Actinobacteria,Bacteroidetes,and Firmicutes both in the CON and HC groups.At the genus level,the HC cows displayed an improved proportion of Labrys(P=0.015)compared with the CON cows.Results of both the principal components analysis and partial least squares of discriminant analysis of milk metabolome revealed that samples of the CON and HC groups clustered separately.A total of 31 differential metabolites were identified between the two groups.Of these,the levels of 11 metabolites decreased(α-linolenic acid,prostaglandin E2,L-lactic acid,L-malic acid,3-hydroxysebacic acid,succinyladenosine,guanosine,pyridoxal,L-glutamic acid,hippuric acid,and trigonelline),whereas the levels of the other 20 metabolites increased in the HC group with respect to the CON group(P<0.05).Conclusion These results suggested that subacute ruminal acidosis less impacted the diversity and composition of milk microbiota,but altered the milk metabolic profiles,which led to the decline of the milk quality.

关键词： High-concentrate diet Milk bacteria Milk metabolome Milk quality Subacute ruminal acidosis

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Physiological and Biochemical Mechanisms of Exogenous Calcium Chloride on Alleviating Salt Stress in Two Tartary Buckwheat(Fagopyrum tataricum)Varieties Differing in Salinity Tolerance

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Phyton-International Journal of Experimental Botany 2022年第8期91卷 1643-1658页

作者： tao Zhang Hongbing Yang Key Laboratory of Plant Biotechnology in Universities of Shandong Province College of Life ScienceQingdao Agricultural UniversityQingdao266109China

Salt stress is one of the most serious abiotic stresses limiting plant growth and development.Calcium as an essential nutrient element and important signaling molecule plays an important role in ameliorating the adverse effect of salinity on plants.This study aimed to investigate the impact of exogenous calcium on improving salt tolerance in Tartary buckwheat cultivars,cv.Xinong9920(salt-tolerant)and cv.Xinong9909(salt-sensitive).Four-week-old Tartary buckwheat seedlings under 100 mM NaCl stress were treated with and without exogenous calcium chloride(CaCl_(2)),Ca^(2+)chelator ethylene glycol tetraacetic acid(EGTA)and Ca^(2+)-channel blocker lanthanum chloride(LaCl_(3))for 10 days.Then,some important physiological and biochemical indexes were determined.The results showed that salt stress significantly reduced seedling growth,decreased photosynthetic pigments,inhibited antioxidants and antioxidant enzyme activities.However,it increased the reactive oxygen species(ROS)levels in the two Tartary buckwheat cultivars.Exogenous 10 mM CaCl_(2)application on salt-stressed Tartary buckwheat seedlings obviously mitigated the negative effects of NaCl stress and partially restored seedlings growth.Ca^(2+)-treated salt-stressed seedlings diplayed a suppressed accumulation of ROS,increased the contents of total chlorophyll,soluble protein,proline and antioxidants,and elevated the activities of antioxidant enzymes compared with salt stress alone.On the contrary,the addition of 0.5 mM LaCl_(3)and 5 mM EGTA on salt-stressed Tartary buckwheat seedlings exhibited the opposite effects to those with CaCl_(2)treatment.These results indicate that exogenous Ca^(2+)can enhance salt stress tolerance and Ca^(2+)supplementation may be an effective practice to cultivate Tartary buckwheat in saline soils.

关键词： Salt stress calcium antioxidant enzymes ROS scavenging osmoprotection tartary buckwheat

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Deep Reinforcement Learning Based Mobile Robot Navigation:A Review

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Tsinghua Science and Technology 2021年第5期26卷 674-691页

作者： Kai Zhu tao Zhang the Department of Automation Tsinghua UniversityBeijing 100084China the Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

Navigation is a fundamental problem of mobile robots,for which Deep Reinforcement Learning(DRL)has received significant attention because of its strong representation and experience learning abilities.There is a growing trend of applying DRL to mobile robot navigation.In this paper,we review DRL methods and DRL-based navigation frameworks.Then we systematically compare and analyze the relationship and differences between four typical application scenarios:local obstacle avoidance,indoor navigation,multi-robot navigation,and social navigation.Next,we describe the development of DRL-based navigation.Last,we discuss the challenges and some possible solutions regarding DRL-based navigation.

关键词： mobile robot navigation obstacle avoidance deep reinforcement learning

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Closed-form solution to the dynamic programming for a heavy-duty parallel hybrid vehicle energy management

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Journal of Control and Decision 2024年第1期11卷 107-116页

作者： tao Zhang Zhongjun Yu Huangda Lin National Key Laboratory for Vessel Integrated Power System Technology Naval University of EngineeringWuhanPeople’s Republic of China

Dynamic programming(DP)is frequently used to obtain the optimal solution to the hybrid electric vehicle(HEV)energy management.The trade-off between the accuracy and the computational effort is the biggest problem for the DP method.The closed-form solution to the DP is proposed to solve this problem.Firstly,the affine linear model of the engine fuel rate is obtained based on engine test data.The piecewise linear approximation of the motor power demand is obtained considering the different energy flows in the charging and discharging stages of the battery.Then,the second-order Taylor expansion for the cost matrix at each time and state grid point is introduced to get the closed-form solution of the optimal torque split.The results show that this method can greatly reduce the computing burden by 93%while ensuring near-optimal fuel economy compared with the conventional DP method.

关键词： Dynamic programming energy management closed-form solutions fuel economy hybrid electric vehicles

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Recent advances in single-crystalline two-dimensional polymers:Synthesis,characterization and challenges

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Chinese Chemical Letters 2022年第12期33卷 4989-5000页

作者： Haoyong Yang tao Zhang Qunji Xue Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China School of Chemical Sciences University of Chinese Academy of SciencesBeijing 100049China

Two-dimensional polymers(2DPs)are emerging crystalline 2D organic material comprising free-standing,single-atom/monomer-thick,planar,and covalent networks with long-ranging structural order.Benefiting from their intrinsic porosity,crystallinity,and electrical properties,2DPs have displayed great potential for separation,energy conversion and electronic fields.In this mini review,we aim to provide the recent progress in crystalline 2DPs films form synthesis strategies to characterization methods,as well as the future trends.We first present the synthesis strategy of single-crystalline 2DPs films including crystal engineering approaches and surface science.Also,we summarize the characterization methods of 2DPs films and highlight the advantages and limitations of different methods focusing on chemical bonding,morphology,and crystal structure.Finally,we will present the current challenges and trends regarding the future developments of crystallinity,monomer design,synthesis strategy and characterization.

关键词： 2D polymer Single crystal Organic thin film Interfacial synthesis Structural characterization

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ALKBH5 suppresses autophagic flux via N6-methyladenosine demethylation of ZKSCAN3 mRNA in acute pancreatitis

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World Journal of Gastroenterology 2024年第12期30卷 1764-1776页

作者： tao Zhang Shuai Zhu Geng-Wen Huang Department of General Surgery Xiangya HospitalCentral South UniversityChangsha 410005HunanChina. National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangsha 410005HunanChina.

BACKGROUND Increasing evidence has demonstrated that N6-methyladenosine(m6A)RNA modification plays an essential role in a wide range of pathological conditions.Impaired autophagy is a critical hallmark of acute pancreatitis(AP).AIM To explore the role of the m6A modification of ZKSCAN3 in the regulation of autophagy in AP.METHODS The AP mouse cell model was established by cerulein-treated mouse pancreatic acinar cells(MPC-83),and the results were confirmed by the levels of amylase and inflammatory factors.Autophagy activity was evaluated by specific identification of the autophagy-related microstructure and the expression of autophagy-related genes.ZKSCAN3 and ALKBH5 were knocked down to study the function in AP.A m6A RNA binding protein immunoprecipitation assay was used to study how the m6A modification of ZKSCAN3 mRNA is regulated by ALKBH.RESULTS The increased expression of amylase and inflammatory factors in the supernatant and the accumulation of autophagic vacuoles verified that the AP mouse cell model was established.The downregulation of LAMP2 and upregulation of LC3-II/I and SQSTM1 demonstrated that autophagy was impaired in AP.The expression of ZKSCAN3 was upregulated in AP.Inhibition of ZKSCAN3 increased the expression of LAMP2 and decreased the expression of the inflammatory factors,LC3-II/I and SQSTM1.Furthermore,ALKBH5 was upregulated in AP.Knockdown of ALKBH5 downregulated ZKSCAN3 expression and restored decreased autophagic flux in AP.Notably,the bioinformatic analysis revealed 23 potential m6A modification sites on ZKSCAN3 mRNA.The m6A modification of ZKSCAN3 mRNA was significantly decreased in AP.Knockdown of ALKBH5 increased the modification of ZKSCAN3 mRNA,which confirmed that ALKBH5 upregulated ZKSCAN3 expression in a m6A-dependent manner.CONCLUSION ALKBH5 inhibits autophagic flux through m6A demethylation of ZKSCAN3 mRNA in AP,thereby aggravating the severity of the disease.

关键词： Acute pancreatitis Autophagy ZKSCAN3 N6-methyladenosine ALKBH5

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Wear mechanism and debris analysis of PEEK as an alternative to CoCrMo in the femoral component of total knee replacement

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Friction 2023年第10期11卷 1845-1861页

作者： Xinyue zhang tao Zhang Kai CHEN Handong XU Cunao FENG Dekun zhang School of Mechatronic Engineering China University of Mining and TechnologyXuzhou 221116China School of Materials and Physics China University of Mining and TechnologyXuzhou 221116China

The polyetheretherketone(PEEK)-highly cross-linked polyethylene(XLPE),all-polymer knee prosthesis has excellent prospects for replacing the traditional metal/ceramic-polyethylene joint prosthesis,improving the service life of the joint prosthesis and the quality of patients’life.The long-term wear mechanism of PEEK-XLPE knee joint prosthesis is comprehensively evaluated from wear amount,wear morphology,and wear debris compared to that of CoCrMo-XLPE joint prosthesis.After 5 million cycles of in vitro wear,the wear loss of XLPE in PEEK-XLPE(30.9±3.2 mg)is lower than that of XLPE in CoCrMo-XLPE(32.1±3.1 mg).Compared to the XLPE in CoCrMo-XLPE,the plastic deformation of XLPE in PEEK-XLPE is more severe in the early stage,and the adhesive peeling and adhesion are lighter in the later stage.The size distribution of XLPE wear debris in PEEK-XLPE is relatively dispersed,which in CoCrMo-XLPE is relatively concentrated.Wear debris is mainly flake and block debris,and the wear mechanism of XLPE was abrasive wear.The wear volume per unit area of PEEK femoral condyle(10.45×10^(5)μm^(3)/mm^(2))is higher than that of CoCrMo(8.32×10^(5)μm^(3)/mm^(2)).The PEEK surface is mainly furrows and adhesions,while the CoCrMo surface is mainly furrows and corrosion spots.The PEEK wear debris is mainly in flakes and blocks,and the CoCrMo wear debris is mainly in the shape of rods and blocks.The wear mechanism of PEEK is abrasive wear and adhesion,and that of CoCrMo is abrasive wear and corrosion.

关键词： polyetheretherketone(PEEK)-highly cross-linked polyethylene(XLPE) cobalt-chromium-molybdenum(CoCrMo)-XLPE wear debris wear mechanism

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