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Influence of K plus on the crystal structure, defect, and scintillation performances of LYSO:Ce crystals

JOURNAL OF ALLOYS AND COMPOUNDS 2024年 998卷

作者： Qiu, Peng Xue, Zhongjun Li, Chengyi Zhang, Aochen zhao, shuwen Zheng, Xiang Zhang, Zhe Ding, Dongzhou Chinese Acad Sci Shanghai Inst Ceram Shanghai 201899 Peoples R China Univ Chinese Acad Sci Ctr Mat Sci & Optoelect Engn Beijing 100049 Peoples R China

Lu 1.8 Y 0.2 SiO 5 :Ce (LYSO:Ce) crystals have become the material of choice for the current application of commercial TOF-PETs due to their high light output, short decay time, and fast rise time. In this study, a series of K + co-doped LYSO:Ce crystals were prepared by the mu-PD method, in which the K + concentrations were 0, 0.2 atom %, 0.6 atom %, and 1.0 atom %, respectively. It was found that the scintillation performances were simultaneously optimized when the K + concentration was 0.6 atom %. Compared to the sample of LYSO:Ce, LYSO:Ce, 0.6 atom % K showed an approximately 12.6 % increase in light yield, a shortening of the fastest scintillation decay time to 38.3 ns, and a 1.4-fold decrease in afterglow level. Moreover, the K + could replace the Lu 3 + site but could not cause the transition of Ce 3 + to Ce 4 + . Meanwhile, the connection between optical and luminescence performances and K + concentration was discussed. The luminescence contribution of Ce2 became stronger with the K + concentration increased. Furthermore, the research on K + co-doping of LYSO:Ce crystals could offer better knowledge and be informative for the selection of future co-dopants.

关键词： Optical materials Oxide materials Crystal growth Crystal structure Optical spectroscopy

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Investigation of the Mechanism of Heterovalent Codoping on the Scintillation Properties of GAGG:Ce Crystals

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CRYSTAL GROWTH & DESIGN 2024年第7期24卷 3002-3009页

作者： Zhang, Aochen Li, Chengyi Xue, Zhongjun zhao, shuwen Qiu, Peng Zhang, Zhe Zheng, Xiang Ding, Dongzhou Chinese Acad Sci Shanghai Inst Ceram Shanghai 201899 Peoples R China Univ Chinese Acad Sci Ctr Mat Sci & Optoelect Engn Beijing 100049 Peoples R China

Gd-3(Al,Ga)(5)O-12:Ce (GAGG:Ce) crystal is considered as one of the most efficient scintillators for nuclear medicine imaging devices and gamma detection applications due to its high light yield (58,000 ph./MeV), excellent energy resolution (4.9%@662 keV), and high density (6.63 g/cm(3)). With the introduction of time-of-flight techniques, scintillators are required to have a faster scintillation decay time and higher light yield. An efficient strategy for accelerating the scintillation decay process of GAGG:Ce is mainly through the codoping of low valence ions such as Ca2+. However, the mechanism of codoping has not yet been elucidated, and there is no reasonable explanation for the phenomenon of insignificant improvement in scintillation performance after codoping with some low-valence ions (e.g., Na+). To further investigate the effect of valence on the scintillation properties, three ions with different valence states (Mg2+, Yb3+, and Hf4+) are selected. The scintillation properties deteriorate after Hf4+ codoping, whereas the scintillation decay process is significantly accelerated after Mg2+ and Yb3+ codoping. In addition, the Mg2+ codoped crystal exhibits a low afterglow level. These excellent performances make it very promising for detector applications. Furthermore, the theoretical study of the luminescence mechanism provides a significant reference for the design of high-performance codoped GAGG:Ce crystals.

关键词： Crystals Ions Lattices Luminescence Particulate matter

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Polyvinyl chloride microplastics disseminate antibiotic resistance genes in Chinese soil: A metagenomic analysis

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JOURNAL OF HAZARDOUS MATERIALS 2024年 479卷 135727页

作者： zhao, shuwen Zhang, Qianru Huang, Qilan Zhang, Chuchen Li, Hongna Siddique, Kadambot H. M. Chinese Acad Agr Sci Inst Agr Resources & Reg Planning State Key Lab Efficient Utilizat Arid & Semiarid A Beijing 100081 Peoples R China Chinese Acad Agr Sci Inst Environm & Sustainable Dev Agr Beijing 100081 Peoples R China Univ Western Australia UWA Inst Agr Perth WA 6001 Australia

The widespread prevalence of microplastics (MPs) in the environment poses concerns as they are vectors of antibiotic resistance genes (ARGs). The relationships between antibiotic resistomes and MPs remain unexplored in soil which was considered as the reservoirs of MPs and ARGs. This study investigated the effects of polyvinyl chloride (PVC) MPs on soil bacterial communities and ARG abundance which soil samples sourced from 20 provinces across China. We found that PVC significantly influences soil bacterial community structure and ARG abundance. Structural equation modeling revealed that PVC alters soil characteristics, ultimately affecting soil bacterial communities, including ARG-containing bacterial hosts, and the relative abundance of ARGs. This study enhances our understanding of how MPs influence the proliferation and hosts of ARGs within diverse soil environments, offering crucial insights for future strategies in plastic management and disposal.

关键词： Polyvinyl chloride Antibiotic resistance genes (ARGs) Soil

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公司濒临破产时董事破产申请义务的立法建构

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学术论坛 2024年第1期47卷 60-78页

作者：赵树文河北大学法学院河北保定071002

公司濒临破产时已经或者即将失去债务清偿能力,此时的经营风险将由股东向债权人进行转移。董事破产申请义务是助力债权人应对上述风险的重要支点,因为这一制度能够有效地遏制股东、董事以及债权人内部的机会主义行为,防止公司资产的持... 详细信息

公司濒临破产时已经或者即将失去债务清偿能力,此时的经营风险将由股东向债权人进行转移。董事破产申请义务是助力债权人应对上述风险的重要支点,因为这一制度能够有效地遏制股东、董事以及债权人内部的机会主义行为,防止公司资产的持续恶化。在学理上,“直接义务论”和“间接义务论”都可以为其立法建构提供逻辑支持,前者强调当公司濒临破产时董事对债权人直接承担信义义务,后者则认为此时董事依然对公司整体承担信义义务,但是应在决策中重点考量债权人利益。从我国公司治理实践来看,也有推进该制度立法建构的现实需求,包括平衡认缴资本制对法定资本规则的弱化、弥补破产程序启动规制的不足、顺应董事会中心主义治理模式的发展以及填补公司法与破产法之间的制度缝隙等。无论是德国和奥地利对该制度的明确规定,还是美国的“加深破产理论”与英国的“不当交易条款”等功能性替代规定,都能够为我国的立法提供参考。就具体的本土方案而言,可以“直接义务论”为指引,将该制度嵌入破产法体系之中。同时,围绕董事破产申请义务触发条件的界定、董事破产申请义务启动主体构成边界的明晰、董事破产申请义务限制期限的规制、董事破产申请义务中重整程序的融入、董事违反破产申请义务的责任承担以及董事违反破产申请义务的债权人追诉机制等相关内容,建构系统化的具体规则。

关键词： 2023年《公司法》濒临破产董事破产申请义务企业破产法

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Vision-Based Gaze Estimation: A Review

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IEEE TRANSACTIONS ON COGNITIVE AND DEVELOPMENTAL SYSTEMS 2022年第2期14卷 316-332页

作者： Wang, Xinming Zhang, Jianhua Zhang, Hanlin zhao, shuwen Liu, Honghai Harbin Inst Technol Shenzhen State Key Lab Robot & Syst Sch Mech & Automat Shenzhen 518055 Peoples R China Tianjin Univ Technol Sch Comp Sci & Engn Tianjin 300384 Peoples R China Univ Portsmouth Sch Comp Portsmouth PO1 3HE Hants England

Eye gaze is an important natural behavior in social interaction as it delivers complex exchanges between observer and observed, by building up the geometric constraints and relation of the exchanges. These interperson exchanges can be modeled based on gaze direction estimated using computer vision. Despite significant progresses in vision-based gaze estimation in last 10 years, it is still nontrivial since the accuracy of gaze estimation is significantly affected by such intrinsic factors as head pose variance, individual bias between optical axis and visual axis, eye blink, occlusion and image blur, degrade gaze features, lead to inaccurate gaze-involved human social interaction analysis. This article aims to review and discuss existing methods addressing above-mentioned problems, gaze involved applications and data sets against the state of the arts in vision-based gaze estimation. It also points out future research directions and challenges of gaze estimation in terms of metalearning, causal inference, disentangled representation, and social gaze behavior for unconstrained gaze estimation.

关键词： Estimation Feature extraction Faces Three-dimensional displays Solid modeling Iris Visualization 3-D gaze estimation computer vision head pose optical axis visual axis

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Snow-Enhancement Conditions and Seeding Simulation of Stratiform Clouds in the Bayanbulak Test Area in China

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Journal of Meteorological Research 2024年第6期38卷 1078-1092页

作者： Lei WEI Yueqin SHI Weiguo LIU Gang LI Wenhao HU Miao CAI Hengchi LEI shuwen zhao Yuan FU CMA Weather Modification Centre China Meteorological Administration(CMA)Beijing100081China Meteorological Bureau of Bayingol Mongolian Autonomous Prefecture Korla841000China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing100029China Zhejiang Meteorological Observatory Hangzhou310000China

In this study,we employed a three-dimensional mesoscale cold-cloud seeding model to simulate the microphysical impacts of artificial ice crystals used as cloud seeding *** objective was to elucidate the mechanism of snowfall enhancement in stratiform clouds in the Bayanbulak test area of Xinjiang,*** results indicated that the optimal seeding time was the early stages of weather system *** this case,the optimal seeding zone was identified as the northwest of the test area,especially near the cloud top(altitudes between 3500 and 4000 m,temperatures range−11 to−15℃),and the ideal concentration of catalyst was with ice crystal density of 1.0×10^(7)kg^(−1)within the target *** such conditions,the total precipitation rate in the seeding-affected area increased to 50.1 mm h^(−1).The results also showed that the favorable seeding region was featured by high content of supercooled water and low population of natural ice crystals,where artificial ice crystals could substantially increase the *** augmentation typically appeared in a unimodal pattern,with the peak formed within 2–3 h after *** in the ice–water mixed zone of a supercooled cloud facilitated rapid ice crystal growth to snow-flake pieces via the Bergeron process,which in turn consumed more supercooled water via collision–coalescence with cloud water ***,the intensive consumption of supercooled water impeded the riming process and reduced the formation of graupel particles within the *** dispersion of artificial ice crystals extended over tens of kilometers horizontally;however,in the vertical direction most particles remained approximately 1 km below the seeding layer,due to limited vertical ascent rate in the stratiform clouds restricting upward movement of artificial ice *** above results help better understand the snowfall enhancement mechanism in stratiform clouds and facilitate related weather modification practice.

关键词： cloud seeding condition artificial ice crystal seeding simulation snow enhancement effect

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民营经济促进法的立法建构——兼评《中华人民共和国民营经济促进法(草案征求意见稿)》

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学术论坛 2024年第6期47卷 1-20页

作者：赵树文河北大学法学院河北保定071002

民营经济促进法的建构是当下我国法治建设进程中一项重要而紧迫的任务,虽然《中华人民共和国民营经济促进法(草案征求意见稿)》已经正式发布,但是其在目标定位、原则确立以及规则建构方面仍存有尚待商榷之处。因此,有必要坚持理论导向... 详细信息

民营经济促进法的建构是当下我国法治建设进程中一项重要而紧迫的任务,虽然《中华人民共和国民营经济促进法(草案征求意见稿)》已经正式发布,但是其在目标定位、原则确立以及规则建构方面仍存有尚待商榷之处。因此,有必要坚持理论导向与问题导向相融合的立法思维模式,沿着“法理支点、现实需求、基本使命、精神统领以及制度表达”等核心议题,对该法的建构继续进行深度的理论挖掘与缜密的制度考究。具体而言,该法建构的法理支点在于其法律位阶的提升;现实需求体现着该法建构的直接动因,从不同维度可以将其归因于激活市场经济内生动力、拓补多元资本立法体系、优化民主政治建设环境、推进科技创新发展速度以及提升国际贸易竞争优势等方面;基本使命聚焦对民营企业的产权保护;精神统领源自平等原则;制度表达则建议包括总则、平等准入、投资融资促进、科技创新、规范经营、服务保障、权益保护以及法律责任等相关规范。

关键词：民营经济促进型立法产权保护平等保护

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Potentially toxic elements in surface sediments of the Beibu Gulf, South Sea , China: Occurrence, bioavailability and probabilistic risk assessment

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MARINE POLLUTION BULLETIN 2024年第PT A期209卷 117091页

作者： Su, Qiongyuan Cheng, Yanan Huang, Liangliang zhao, shuwen Ma, Jie Song, Shijie Li, Nan Xu, Hao Wang, Caiguang Guilin Univ Technol Coll Environm Sci & Engn Guilin 541004 Peoples R China Guangxi Collaborat Innovat Ctr Water Pollut Contro Guilin 541004 Peoples R China Guangxi Key Lab Environm Pollut Control Theory & T Guilin 541004 Peoples R China Guangdong Ocean Univ Coll Ocean & Meteorol Key Lab Climate Resources & Environm Continental S Dept OceanogKey Lab Coastal Ocean Variat & Disast Zhanjiang 524088 Peoples R China

At present, pollution of gulf sediments with potentially toxic elements (PTEs) has become a prominent marine environmental problem. This study thoroughly investigated the occurrence, bioavailability, and probabilistic risk of PTEs in the surface sediments of the Beibu Gulf. The average total concentrations (mg/kg) were 8.03 for As, 0.06 for Cd, 52.73 for Cr, 9.86 for Cu, 0.04 for Hg, 18.70 for Ni, 27.77 for Pb and 59.80 for Zn, respectively. The positive matrix factorization model revealed that the PTE enrichment was primarily due to composite sources from aquaculture and fisheries activities, industrial and agricultural sources. Risk assessment code and correlation analysis indicated that Cd had the highest bioavailability, influenced by TOC and TP. The probabilistic risk assessment model estimated a 60.83 % probability that the mixed PTEs in the Beibu Gulf's surface sediments could have toxic effects on aquatic life. These findings underscore the impact of intensive human activities on PTE pollution and highlight the need for further research on PTE ecotoxicology and pollution control strategies.

关键词： Potentially toxic elements Bioavailability Combined toxicity Sediment Beibu Gulf

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Heavy metals in Lagocephalus spadiceus (Richardson, 1845) from the Beibu Gulf, China: occurrence and health risk assessment

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JOURNAL OF FOOD COMPOSITION AND ANALYSIS 2025年 143卷

作者： Yang, Yiheng Huang, Liangliang zhao, shuwen Wang, Caiguang Lam, Sze Mun Song, Jianqiang Wu, Zhiqiang Song, Wei Guilin Univ Technol Coll Environm Sci & Engn Guilin 541004 Peoples R China Guangxi Collaborat Innovat Ctr Water Pollut Contro Guilin 541004 Peoples R China Guangxi Key Lab Environm Pollut Control Theory & T Guilin 541004 Peoples R China Guangxi VIM Marine Technol Co Ltd Beihai 536000 Peoples R China Chinese Acad Fishery Sci East China Sea Fisheries Res Inst Shanghai 200090 Peoples R China

The bioaccumulation of heavy metals in marine fish poses significant threats to human health through dietary exposure. In this work, the contents of 8 heavy metals (arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), manganese (Mn), nickel (Ni) and lead (Pb)) in different tissues of Lagocephalus spadiceus from the Beibu Gulf in China were investigated based on length, weight, age, and size of the fish. The estimated recoveries ranged from 94.6 % to 103.2 %. The ANOVA test results indicated significant variations in the heavy metals concentrations in different tissues. The liver exhibited the highest bioaccumulation capacity for most heavy metals (0.03-11.44 mg/kg). Liver tissues were found to contain the highest concentration of As (11.44 mg/kg) while the gills were found to contain the most Mn (1.86 mg/kg). Notably, neither sexual dimorphism nor age-dependent accumulation patterns were observed for most metals. Health risk assessment revealed acceptable hazard indices for muscle consumption but identified potential carcinogenic risks from liver intake.

关键词： Fish tissues Health risks Heavy metals Lagocephalus spadiceus

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Metalloid Te-doped NiCoP nanoarrays for efficient hydrogen evolution reaction

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MATERIALS LETTERS 2023年 330卷

作者： zhao, shuwen zhao, Yifan Chen, Ji Zhou, Weijie Dai, Ruijie Yang, Peizhi Zhou, Yao Zhang, Hua Chen, Anran Yunnan Univ Sch Mat & Energy Kunming 650091 Peoples R China Univ Edinburgh Sch Engn Edinburgh EH8 9YL Scotland Yunnan Normal Univ Sch Energy & Environm Sci Kunming 650500 Peoples R China

Doping regulation is a common and effective solution to improve the performance of electrocatalysts. Herein, a metalloid Te-doped NiCoP was developed and synthesized in situ on nickel foam (NiCoP-Te/NF) to reduce the overpotential of the hydrogen evolution reaction (HER). The NiCoP-Te/NF electrocatalyst exhibits superior HER performance with a low overpotential of 71 mV at 10 mA cm-2, as well as remarkable durability in alkaline solutions.

关键词： Metalloid Te Doping NiCoP-Te NF Hydrogen Evolution Reaction

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