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Microplastics in sediment of the Three Gorges Reservoir:abundance and characteristics under different environmental conditions

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Journal of Oceanology and Limnology 2024年第1期42卷 101-112页

作者： wang LI Bo zu Yiwei LIU Juncheng GUO Jiawen LI College of River and Ocean Engineering Chongqing Jiaotong UniversityChongqing 400074China Chongqing Research Academy of Ecology and Environmental Sciences Chongqing 401147China

Freshwater microplastic pollution is an urgent issue of global concern,and research on the distribution in reservoirs is *** investigated the microplastic pollution levels in wet sediments collected from the Three Gorges Reservoir,the largest reservoir of *** show that microplastics were ubiquitous in the sediments of the Three Gorges Reservoir,and their abundance ranged from 59 to 276 pp/kg(plastic particles per kg,dry weight).Economic development and total population were important factors affecting the spatial heterogeneity of microplastic abundance,and the contribution of large cities along the reservoir to microplastic pollution should be paid with more *** microplastics were the most abundant type of microplastic particles in reservoir sediments,whereas polystyrene,polypropylene,and polyamide were the main types of *** apparent spatial heterogeneity in morphology and color of microplastics is attributed to different anthropogenic or landbased pollution ***,the accumulation of microplastics near the inlet of tributaries reflects the role of potential contributors of *** importantly,multiple bisphenols(BPs)and heavy metals detected at the microplastic surfaces indicate that microplastics can act as carriers of these pollutants in the environment in the same way as sediments did,which may alter the environmental fate and toxicity of these ***,we conclude that the Three Gorges Reservoir had been contaminated with microplastics,which posed a stress risk for organisms who ingest them along with their associated pollutants(BPs,heavy metals).

关键词： microplastics Three Gorges Reservoir sediment bisphenol heavy metal

Investigation of MXene nanosheets based radio-frequency electronics by skin depth effect

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Nano Research 2024年第4期17卷 3061-3067页

作者： Rongguo Song Yunfa Si Wei Qian Haoran zu Bilei Zhou Qinglei Du Daping He Yongliang wang Air Force Early Warning Academy Wuhan 430019China Hubei Engineering Research Center of RF-Microwave Technology and Application Wuhan University of TechnologyWuhan 430070China Hainan Research Institute Wuhan University of TechnologySanya 572000China

Various new conductive materials with exceptional properties are utilized for the preparation of electronic *** ultra-high conductivity is crucial to attain excellent electrical ***,there is a lack of systematic research on the impact of conductor material thickness on device ***,we investigate the effect of conductor thickness on power transmission and radiation in radio-frequency(RF)and microwave electronics based on MXene nanosheets material transmission lines and *** MXene transmission line with thickness above the skin depth exhibits a good transmission coefficient of approximately-3.dB,and the realized gain of MXene antennas exceeds 2 ***,the signal transmission strength of MXene antenna with thickness above the skin depth is higher than 5-μm MXene antenna approximately 5.5 *** lines and antennas made from MXene materials with thickness above the skin depth exhibit stable and reliable performance,which has significant implications for obtaining high-performance RF and microwave electronics based on new conductive materials.

关键词： MXene film radiao-frequency electronics antenna transmission line skin depth

Interface interaction between SiO_(2) and magnetite under high temperature:particle migration and inhibition mechanism

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Journal of Iron and Steel Research International 2024年第3期31卷 561-572页

作者： Yao-zu wang Jian-liang Zhang Qiang Cheng Hui-qing Jiang Zheng-jian Liu Yu-bo Tan School of Intelligent Science and Technology University of Science and Technology BeijingBeijing 100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Advanced Engineering University of Science and Technology BeijingBeijing 100083China

Silicon is one of the main gangue components in iron ore,usually in the form of quartz and *** studies have shown that SiO_(2) has a two-sided effect on the consolidation of pellets during high-temperature oxidation roasting of ***,it is very difficult to capture the structural evolution and migration mechanisms during high-tem-perature roasting process by existing experimental ***,the influence of SiO_(2) on the consolidation behavior of magnetite was studied through a series of roasting experiments and molecular dynamic *** results show that the consolidation index and particle growth index decrease with the increase in SiO_(2) content in the *** 1573.K,the liquid phase promotes the recrystallization growth of hematite at high *** dynamic study shows that it is difficult for quartz SiO_(2) to form sintering neck with Fe_(2)O_(3..When the calcination temperature is higher than 1400 K,the Fe_(2)O_(3.-Fe_(2)SiO_(4) system produces a considerable sintering neck structure after *** atomic migration ability of Fe_(2)SiO_(4) is much higher than that of Fe_(2)O_(3..The higher atomic migration ability of Fe_(2)SiO_(4) is the main reason for the formation of the sintering neck.

关键词： Sintering neck Crystal growth Consolidation Molecular dynamics SiO_(2)

Magnesium-containing pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel Research International 2024年第7期31卷 1623-1635页

作者： Li-ming Ma Jian-liang Zhang Yao-zu wang Xiao-yong Ma Gui-lin wang Zhuo Li Hui-qing Jiang Zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group Co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03.1.3. wt.%,controlling the MgO/Al_(2)O_(3. ratio of the mixed burden within 1.15-1.3.,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag

Multi-scale persistent spatiotemporal transformer for long-term urban traffic flow prediction

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Journal of Electronic Science and Technology 2024年第1期22卷 53-69页

作者： Jia-Jun Zhong Yong Ma Xin-Zheng Niu Philippe Fournier-Viger Bing wang zu-kuan Wei School of Computer Science and Engineering University of Electronic Science and Technology of ChinaChengdu611731China College of Computer Science&Software Engineering Shenzhen UniversityShenzhen518060China School of Computer Science Southwest Petroleum UniversityChengdu610500China

Long-term urban traffic flow prediction is an important task in the field of intelligent transportation,as it can help optimize traffic management and improve travel *** improve prediction accuracy,a crucial issue is how to model spatiotemporal dependency in urban traffic *** recent years,many studies have adopted spatiotemporal neural networks to extract key information from traffic ***,most models ignore the semantic spatial similarity between long-distance areas when mining spatial *** also ignore the impact of predicted time steps on the next unpredicted time step for making long-term ***,these models lack a comprehensive data embedding process to represent complex spatiotemporal *** paper proposes a multi-scale persistent spatiotemporal transformer(MSPSTT)model to perform accurate long-term traffic flow prediction in *** adopts an encoder-decoder structure and incorporates temporal,periodic,and spatial features to fully embed urban traffic data to address these *** model consists of a spatiotemporal encoder and a spatiotemporal decoder,which rely on temporal,geospatial,and semantic space multi-head attention modules to dynamically extract temporal,geospatial,and semantic *** spatiotemporal decoder combines the context information provided by the encoder,integrates the predicted time step information,and is iteratively updated to learn the correlation between different time steps in the broader time range to improve the model’s accuracy for long-term *** on four public transportation datasets demonstrate that MSPSTT outperforms the existing models by up to 9.5%on three common metrics.

关键词： Graph neural network Multi-head attention mechanism Spatio-temporal dependency Traffic flow prediction

Comparison of displacement damage effects on the dark signal in CMOS image sensors induced by CSNS back-n and XAPR neutrons

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NUCLEAR SCIENCE AND TECHNIQUES 2024年第10期35卷 1-12页

作者： Xue, Yuan-Yuan wang, zu-Jun Ma, Wu-Ying Liu, Min-Bo He, Bao-Ping Gou, Shi-Long Northwest Inst Nucl Technol State Key Lab Intense Pulsed Irradiat Simulat & Ef Xian 710024 Peoples R China Peking Univ Sch Phys State Key Lab Artificial Microstruct & Microscop P Beijing 100871 Peoples R China

This study investigates the effects of displacement damage on the dark signal of a pinned photodiode CMOS image sensor (CIS) following irradiation with back-streaming white neutrons from white neutron sources at the China spallation neutron source (CSNS) and Xi'an pulsed reactor (XAPR). The mean dark signal, dark signal non-uniformity (DSNU), dark signal distribution, and hot pixels of the CIS were compared between the CSNS back-n and XAPR neutron irradiations. The non-ionizing energy loss and energy distribution of primary knock-on atoms in silicon, induced by neutrons, were calculated using the open-source package Geant4. An analysis combining experimental and simulation results showed a noticeable proportionality between the increase in the mean dark signal and the displacement damage dose (DDD). Additionally, neutron energies influence DSNU, dark signal distribution, and hot pixels. High neutron energies at the same DDD level may lead to pronounced dark signal non-uniformity and elevated hot pixel values.

关键词： Displacement damage effects CMOS image sensor (CIS) CSNS back-n XAPR neutrons Geant4 Dark signal non-uniformity (DSNU) PROTON

Influence of sea-land breeze on the formation and dissipation of severe dense fog and its burst reinforcement in the Yellow Sea coastal area,China

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Science China Earth Sciences 2024年第2期67卷 432-449页

作者： Ya GAO Duanyang LIU Shuqi YAN Wenjun ZHOU Hongbin wang Fan zu Qin MEI Chuanxiang YI Ye SHENG Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing210041China Yancheng Meteorological Bureau Yancheng224000China Nanjing Joint Institute for Atmospheric Sciences Nanjing210041China Key Laboratory of Disaster Weather Chinese Academy of Meteorological SciencesBeijing100086China

Based on the global reanalysis data of the National Centers for Environmental Prediction(NCEP)/National Center for Atmospheric Research,the surface meteorological observation data,sounding data and satellite observation data,this paper comprehensively analyzes the evolution process and formation mechanism of a persistent severe dense fog process occurred on February 15–17,2015 in Yancheng,eastern *** the numerical simulation experiment of Weather Research and Forecast(WRF)model,we further analyze the impact of sea-land breeze on the formation and burst reinforcement of *** show that the precipitation caused by the southwesterly airflow in front of the upper-level trough and the low-pressure inverted trough are conducive to the formation of early rain fog,while the nighttime clear radiance under the control of surface cold high and the infiltration of weak cold advection are conducive to the formation and development of later radiation-advection *** WRF model simulates the fog evolution process,which is basically consistent with the actual fog area,and the simulation results are credible to a certain *** simulation results show that the establishment of sea breeze has an advection cooling effect on the near surface layer,which is conducive to the formation and development of the inversion layer on the near surface,providing stable stratification conditions for the formation and burst reinforcement of *** one hand,the strengthening of sea breeze circulation can continuously transport water vapor to the study *** the other,the occurrence of ultra-low level jet is favorable for the accumulation of low-level water *** the same time,the inversion intensity further strengthens,which is in favor of the burst reinforcement and long-term maintenance of fog.

关键词： Radiation-advection fog Sea-land breeze Atmospheric boundary layer Fog burst reinforcement WRF model

Micro-invasive pancreaticoduodenectomy will be a promising treatment option for distal cholangiocarcinoma

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Hepatobiliary Surgery and Nutrition 2024年第5期13卷 841-844页

作者： Han-Xuan wang zu-Yu wang Ren Lang Qiang He Shao-Cheng Lyu Department of Hepatobiliary and Pancreaticosplenic Surgery Beijing Chaoyang HospitalCapital Medical UniversityBeijingChina

Cholangiocarcinoma is a malignancy derived from biliary epithelial cells,a relatively rare but highly malignant type of *** located below the convergence of gallbladder duct and common hepatic duct is defined as distal cholangiocarcinoma(dCCA),accounting for 20-3.%of total *** spite of the highly developed adjuvant therapy,surgical treatment remains the core in dCCA treatment,and radical pancreaticoduodenectomy is still the only potential cure for ***,the overall prognosis of dCCA after radical surgery is still unsatisfying,with a post-operative 5-year survival rate less than 40%.

关键词： Distal cholangiocarcinoma(dCCA) minimally invasive pancreaticoduodenectomy(MIPD) prognosis

Human bone marrow mesenchymal stem cell-derived exosomes loaded with gemcitabine inhibit pancreatic cancer cell proliferation by enhancing apoptosis

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World Journal of Gastrointestinal Oncology 2024年第9期16卷 4006-4013页

作者： zu-Gui Tang Tie-Mei Chen Yi Lu Zhe wang Xi-Cheng wang Yi Kong Department of Oncology The First Affiliated Hospital of Guangdong Pharmaceutical UniversityGuangzhou 510080Guangdong ProvinceChina Faculty of Pharmaceutical Sciences Shenzhen University of Advanced TechnologyShenzhen 518000Guangdong ProvinceChina Guangdong Pharmaceutical University Guangzhou 510006Guangdong ProvinceChina

BACKGROUND Pancreatic cancer remains one of the most lethal malignancies,and has limited effective ***(GEM),a chemotherapeutic agent,is commonly used for clinical treatment of pancreatic cancer,but it has characteristics of low drug delivery efficiency and significant side *** study tested the hypothesis that human bone marrow mesenchymal stem cell(MSC)-derived exosomes loaded with GEM(Exo-GEM)would have a higher cytotoxicity against human pancreatic cancer cells by enhancing their *** To investigate the cytotoxicity of MSC-derived Exo-GEM against pancreatic cancer cells in *** Exosomes were isolated from MSCs and characterized by transmission electron microscopy and nanoparticle tracking ***-GEM through electroporation,sonication,or incubation,and the loading efficiency was *** cytotoxicity of Exo-GEM or GEM alone against human pancreatic cancer Panc-1 and MiaPaca-2 cells was assessed by MTT and flow cytometry *** The isolated exosomes had an average size of 76.7 *** encapsulation efficacy and loading efficiency of GEM by electroporation and sonication were similar and significantly better than *** cytotoxicity of Exo-GEM against pancreatic cancer cells was stronger than free GEM and treatment with 0.02μM Exo-GEM significantly reduced the viability of both Panc-1 and MiaPaca-2 ***,Exo-GEM enhanced the frequency of GEMinduced apoptosis in both cell *** Human bone marrow MSC-derived Exo-GEM have a potent cytotoxicity against human pancreatic cancer cells by enhancing their apoptosis,offering a promising drug delivery system for improving therapeutic outcomes.

关键词： Mesenchymal stem cells Exosomes Extracellular vesicles Gemcitabine Pancreatic cancer Drug delivery