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Abundance and sources of particulate polycyclic aromatic hydrocarbons and aromatic acids at an urban site in central China

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Journal of Environmental Sciences 2024年第8期142卷 155-168页

作者： Luqi Shang zhe dong Zihan Li Mingkai Wang Zihan Kong Xiao Li Ruiqin Zhang School of Ecology and Environment Zhengzhou UniversityZhengzhou 450001China College of Chemistry Zhengzhou UniversityZhengzhou 450001China Institute of Environmental Sciences Zhengzhou UniversityZhengzhou 450001China

We conducted a simultaneous field study of PM_(2.5)-bound particulate polycyclic aromatic hydrocarbons(PAHs)and aromatic acids(AAs)in a polluted city zhengzhou to explore the concentration,sources and potential conversion pathways between PAHs and AAs in different seasons.The average concentrations of PM_(2.5),28PAHs and 8AAs during the sampling period were 77μg/m^(3),75 ng/m^(3),and 283 ng/m^(3),respectively.The concentration of both28PAHs and 8AAs were highest in winter and lowest in summer with ratios of 6.3 and 2.3,respectively.PAHs with 5-7 rings were the main components of PAHs(52%),followed by 4rings PAHs(30%)and 2-3 rings PAHs(18%).According to the source appointment results obtained by positive matrix factorization,the main sources of PAHs were combustion and vehicle emissions,which account for 37%and 34%,respectively.8AAs were divided into three groups,including four benzene dicarboxylic acids(B2CAs),three benzene tricarboxylic acids(B3CAs)and one benzene tetracarboxylic acid(B4CA).And interspecies correlation analysis with PM_(2.5)source markers were used to investigate potential sources.Phthalic acid(o-Ph)was the most abundant specie of 8AAs(157 ng/m^(3),55%of 8AAs),which was well correlated with sulfate.Meanwhile,B3CAs and B4CA were highly correlated with sulfate and weakly correlated with levoglucosan,suggesting that secondary formation was their main source.As logical oxidation products of PAHs,o-Ph and B3CAs showed good correlations with a number of PAHs,indicating possible photochemical oxidation pathway by PAHs.In addition,O_(3),NO_(2),temperature and relative humidity have positive effects on the secondary formation of B3CAs.

关键词： Polycyclic aromatic hydrocarbons Aromatic acids Source appointment Secondary formation

Fusion network for small target detection based on YOLO and attention mechanism

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Optoelectronics Letters 2024年第6期20卷 372-378页

作者： XU Caie dong zhe ZHONG Shengyun CHEN Yijiang PAN Sishun WU Mingyang School of Information and Electronic Engineering Zhejiang University of Science and TechnologyHangzhou 310012China Research Development Department Hangzhou Xinhe Data Technology Co.Ltd.Hangzhou 311202China College of Mechanical Engineering Zhejiang UniversityHangzhou 310013China

Target detection is an important task in computer vision research, and such an anomaly detection and the topic of small target detection task is more concerned. However, there are still some problems in this kind of researches, such as small target detection in complex environments is susceptible to background interference and poor detection results. To solve these issues, this study proposes a method which introduces the attention mechanism into the you only look once(YOLO) network. In addition, the amateur-produced mask dataset was created and experiments were conducted. The results showed that the detection effect of the proposed mothed is much better.

关键词： Fusion network for small target detection based on YOLO and attention mechanism

Controls of strike-slip fault on fractures:Insight from 3D discrete element simulation

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Science China Earth Sciences 2024年第1期67卷 146-164页

作者： Lianbo ZENG zhe MAO Guoping LIU He TIAN Yingtao YAO Kewei ZU Shaoqun dong Mehdi OSTADHASSAN State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Institute of Energy Peking UniversityBeijing 100871China Exploration and Development Research Institute Zhongyuan Oilfield Branch CompanySINOPECZhengzhou 457001China Northeast Petroleum University Daqing 163318China

The fracture-cave reservoirs controlled by strike-slip faults are the main targets for oil and gas exploration of ultradeep carbonate in the Tarim Basin.It is of great significance to clarify the distribution rules of fractures related to strike-slip faults for guiding the exploration and development of ultra-deep oil and gas.In this study,six groups of strike-slip fault 3D models based on discrete element numerical simulation method have been created to investigate characteristics of fault-related fracture development and distribution law.In addition,we compared the modeling results to the measurement of fractures from the outcrop of a strike-slip fault in the Northern Tarim Basin to verify their validity.The results show that the stress environment is stable in the simple strike-slip section,and fractures intersecting with the strike-slip direction at a small angle are the principal fracture.In the releasing stepover and double-bend sections,the maximum principal stress changes from horizontal to vertical during the formation of pull-apart zones,where the principal fractures intersect the strike-slip direction at a large angle.The maximum principal stress in the restraining stepover and double-bend section remains horizontal,but their strikes change significantly with the increment of fault displacement.Thus,fractures intersecting the strike-slip direction at a small angle will become principal fractures early on,while those parallel to or anti-intersecting the strike-slip direction at a small angle will become principal fractures later.There are obvious differences in the development of fractures in different structural positions of strike-slip faults.Fractures are mainly concentrated in the fault tips,connections,and fault plane,and the magnitude of the fault damage zone is relatively larger in the first two.Compared with fault displacement,the principal damage zone(PDZ)shows stronger control on the distribution and development intensity of fractures.With the increment of fault displacement,the width of the f

关键词： Strike-slip fault Fault-related fracture Stepover Double-bend Discrete element method

Tracing monoclinic distortion in NCM532 cathode materials by in situ high-energy synchrotron X-ray diffraction

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Progress in Natural Science:Materials International 2024年第2期34卷 274-279页

作者： Min dong Qingya Sun Zhihua Wang Zixin Rui zhe Zhang He Zhu Si Lan Herbert Gleiter Institute of Nanoscience School of Materials Science and Engineering Nanjing University of Science and Technology School of Mechanical Engineering Nanjing University of Science and Technology School of Materials Science and Engineering Henan University of Technology Center for Neutron Scattering City University of Hong Kong Shenzhen Research Institute

Layered LiNixCoyMnzO2（NCM） cathode materials have emerged as the best choice for high-energy-density lithium-ion batteries for powering electric vehicles.Despite significant research efforts,the understanding of complex structural dynamics during lithium（de-） intercalation still remains a subject of debate,especially in scenarios where morphology and composition vary.In this study,we carried out in situ high-energy synchrotron X-ray diffraction experiments on commercial NCM523cathode materials in both single crystal and polycrystalline forms to probe the structural changes during charging and discharging in detail.Our findings reveal that both single crystal and polycrystalline materials exhibit typical H1-H2-H3 phase transitions.However,in polycrystalline NCM532,a monoclinic intermediate phase emerges between the H1 and H2 phases.During this process,symmetry reduces from R-3m to C2/m,which is attributed to a shear distortion along the ab plane.In contrast,for single crystal materials,the H1 phase directly transforms into the H2 phase without the monoclinic phase.The observed monoclinic distortion significantly impacts structural stability and material cycling performance.This study provides new insight into the structural dynamics in NCM532 cathode materials,particularly concerning morphology-dependent behaviors,which could deepen our understanding of the relationship between NCM material structures and their performance.

关键词： CHEMISTRY

Collembolans maintain a core microbiome responding to diverse soil ecosystems

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Soil Ecology Letters 2024年第1期6卷 33-46页

作者： zhe-Lun Liu dong Zhu Yi-Fei Wang Yong-Guan Zhu Min Qiao State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China

The unique gut habitat led to a core intestinal micro-biome in diverse soil ecosystems.The collembolan guts may help eliminate soil pathogens.Host-selection carried more weight on community assembly of gut microbiome.Soil invertebrates are widely distributed in the ecosystem and are essential for soil ecological processes.Inverte-brate gut microbiome plays an important role in host health and has been considered as a hidden microbial repository.However,little is known about how gut microbiome in soil invertebrates respond to diverse soil ecosystems.Based on a laboratory microcosm experiment,we characterized the assembling of microbiome of soil collembolans(Folsomia candida)from six representative regions of the soil ecosystem which they inhabit.Results showed that collembolan gut microbial communities differed significantly from their surrounding soil microbial communities.A dominant core gut microbiome was identified in gut habitat.Community analyses indicated that deterministic process dominated in the community assembly of collembolan gut microbiome.The results further demonstrate a dominant contribution of host selection in shaping gut microbiome.It is also worthy to mention that pathogens,such as common agricultural phytopathogenic fungi Fusarium,were involved in core microbiome,indicating that collembolans could act as vectors of pathogens.Our results unravelled the existence of gut core microbiome of collembolans in soil ecosystems and provided new insights for under-standing the crucial role of gut microbiome of soil fauna in maintaining microbial biodiversity and stability of soil ecosystems.

关键词： gut microbiome collembolan core microbiome community assembly

Mesenteric adipose tissue B lymphocytes promote intestinal injury in severe acute pancreatitis by mediating enteric pyroptosis

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Hepatobiliary & Pancreatic Diseases International 2024年第3期23卷 300-309页

作者： Qing Huang Jia-Wen Liu Hai-Bin dong zheng-Jie Wei Jin-zhe Liu Yu-Tang Ren Xuan Jiang Bo Jiang Department of Gastroenterology Beijing Tsinghua Changgung HospitalSchool of Clinical MedicineTsinghua UniversityBeijing 102218China

Background:Visceral adipose tissue(VAT)has been linked to the severe acute pancreatitis(SAP)prognosis,although the underlying mechanism remains unclear.It has been reported that pyroptosis worsens SAP.The present study aimed to verify whether mesenteric adipose tissue(MAT,a component of VAT)can cause secondary intestinal injury through the pyroptotic pathway.Methods:Thirty-six male Sprague Dawley(SD)rats were divided into six different groups.Twelve rats were randomly divided into the SAP and control groups.We monitored the changes of MAT and B lymphocytes infiltration in MAT of SAP rats.Twelve SAP rats were injected with MAT B lymphocytes or phosphate buffer solution(PBS).The remaining twelve SAP rats were first injected with MAT B lymphocytes,and then with MCC950(NLRP3 inhibitor)or PBS.We collected blood and tissue samples from pancreas,gut and MAT for analysis.Results:Compared to the control rats,the SAP group showed inflammation in MAT,including higher expression of tumor necrosis factor(TNF-α)and interleukin-6(IL-6),lower expression of IL-10,and histological changes.Flow cytometry analysis revealed B lymphocytes infiltration in MAT but not T lymphocytes and macrophages.The SAP rats also exhibited intestinal injury,characterized by lower expression of zonula occludens-1(ZO-1)and occludin,higher levels of lipopolysaccharide and diamine oxidase,and pathological changes.The expression of NLRP3 and n-GSDMD,which are responsible for pyroptosis,was increased in the intestine of SAP rats.The injection of MAT B lymphocytes into SAP rats exacerbated the inflammation in MAT.The upregulation of pyroptosis reduced tight junction in the intestine,which contributed to the SAP progression,including higher inflammatory indicators and worse histological changes.The administration of MCC950 to SAP+MAT B rats downregulated pyroptosis,which subsequently improved the intestinal barrier and ameliorated inflammatory response of SAP.Conclusions:In SAP,MAT B lymphocytes aggravated local inflammation,and promoted the injury to the int

关键词： Acute pancreatitis Mesenteric adipose tissue B lymphocyte Intestinal barrier Pyroptosis

Constructing inter-diffusive PtCuNi/WO_(3)interface to enhance the catalytic activity and stability in oxygen reduction

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Tungsten 2024年第2期6卷 293-303页

作者： Hao-zhe Xu dong Li Ying Chen Pin Fang Xiao-Xing Ke Olga Demidenko Yu-Jing Li Beijing Key Laboratory of Construction Tailorable Advanced Functional Materials and Green Applications Experimental Center of Advanced MaterialsSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China Scientifi c-Practical Materials Research Centre National Academy of Sciences of Belarus220072 MinskBelarus

Platinum-group-metal-based alloy nanocrystals have been considered as the most effi cient catalysts for oxygen reduction reaction(ORR).However,the poor stability issues limit their further deployment in industrialization.Tungsten oxide(WO_(3))has received attention due to its intrinsic electrochemical stability and proton absorption/desorption capability.In this work,we prepared PtCuNi/WO_(3)/C hybrid catalyst with inter-diff usive alloy/WO_(3)interface on carbon.The catalyst exhibits enhanced activity and stability associated with the WO_(3)content.The characterization results suggest that the increased activity originates from the complementary proton supply of non-stoichiometric H_(x)WO_(3).Moreover,WO_(3)prevents the particle from dissolution and detachment under vigorous electrochemical polarizations.The enhanced stability originates from the electronic interaction established between Pt and W.This work provides new strategies to design high-performance ORR catalysts by taking the merits of WO_(3)。

关键词： Tungsten oxide PtCuNi Interface Electronic interaction

Influence of heat treatment on microstructure,mechanical and corrosion behavior of WE43 alloy fabricated by laser-beam powder bed fusion

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International Journal of Extreme Manufacturing 2024年第1期6卷 258-275页

作者： Chenrong Ling Qiang Li zhe Zhang Youwen Yang Wenhao Zhou Wenlong Chen Zhi dong Chunrong Pan Cijun Shuai College of Mechanical and Electrical Engineering Jiangxi University of Science and TechnologyGanzhou 341000People’s Republic of China School of Mechanical and Electronic Engineering Suzhou UniversitySuzhou 234000People’s Republic of China Shaanxi Key Laboratory of Biomedical Metal Materials Northwest Institute for Non-ferrous Metal ResearchXi’an 710016People’s Republic of China Department of Orthopedics First Afffliated Hospital of Gannan Medical CollegeGanzhou 341000People’s Republic of China School of Mechanical and Automotive Engineering South China university of technologyGuangzhou 510641People’s Republic of China State Key Laboratory of High-Performance Complex Manufacturing Central South UniversityChangsha 410083People’s Republic of China Double Medical Technology Inc. Xiamen 361026People’s Republic of China

Magnesium(Mg)alloys are considered to be a new generation of revolutionary medical metals.Laser-beam powder bed fusion(PBF-LB)is suitable for fabricating metal implants withpersonalized and complicated structures.However,the as-built part usually exhibits undesirable microstructure and unsatisfactory performance.In this work,WE43 parts were firstly fabricated by PBF-LB and then subjected to heat treatment.Although a high densification rate of 99.91%was achieved using suitable processes,the as-built parts exhibited anisotropic and layeredmicrostructure with heterogeneously precipitated Nd-rich intermetallic.After heat treatment,fine and nano-scaled Mg24Y5particles were precipitated.Meanwhile,theα-Mg grainsunderwent recrystallization and turned coarsened slightly,which effectively weakened thetexture intensity and reduced the anisotropy.As a consequence,the yield strength and ultimate tensile strength were significantly improved to(250.2±3.5)MPa and(312±3.7)MPa,respectively,while the elongation was still maintained at a high level of 15.2%.Furthermore,the homogenized microstructure reduced the tendency of localized corrosion and favoredthe development of uniform passivation film.Thus,the degradation rate of WE43 parts was decreased by an order of magnitude.Besides,in-vitro cell experiments proved their favorable biocompatibility.

关键词： laser-beam powder bed fusion WE43 alloys heat treatment mechanical performance biodegradation behavior

Esophageal cancer screening,early detection and treatment:Current insights and future directions

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1180-1191页

作者： Hong-Tao Qu Qing Li Liang Hao Yan-Jing Ni Wen-Yu Luan zhe Yang Xiao-dong Chen Tong-Tong Zhang Yan-dong Miao Fang Zhang Department of Emergency Yantai Mountain HospitalYantai 264000Shandong ProvinceChina Cancer Center Yantai Affiliated Hospital of Binzhou Medical UniversityThe 2nd Medical College of Binzhou Medical UniversityYantai 264100Shandong ProvinceChina

Esophageal cancer ranks among the most prevalent malignant tumors globally,primarily due to its highly aggressive nature and poor survival rates.According to the 2020 global cancer statistics,there were approximately 604000 new cases of esophageal cancer,resulting in 544000 deaths.The 5-year survival rate hovers around a mere 15%-25%.Notably,distinct variations exist in the risk factors associated with the two primary histological types,influencing their worldwide incidence and distribution.Squamous cell carcinoma displays a high incidence in specific regions,such as certain areas in China,where it meets the cost-effect-iveness criteria for widespread endoscopy-based early diagnosis within the local population.Conversely,adenocarcinoma(EAC)represents the most common histological subtype of esophageal cancer in Europe and the United States.The role of early diagnosis in cases of EAC originating from Barrett's esophagus(BE)remains a subject of controversy.The effectiveness of early detection for EAC,particularly those arising from BE,continues to be a debated topic.The variations in how early-stage esophageal carcinoma is treated in different regions are largely due to the differing rates of early-stage cancer diagnoses.In areas with higher incidences,such as China and Japan,early diagnosis is more common,which has led to the advancement of endoscopic methods as definitive treatments.These techniques have demonstrated remarkable efficacy with minimal complications while preserving esophageal functionality.Early screening,prompt diagnosis,and timely treatment are key strategies that can significantly lower both the occurrence and death rates associated with esophageal cancer.

关键词： Esophageal cancer Screening Early detection Treatment Endoscopic mucosal resection Endoscopic submucosal dissection