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Nano Research 2024年第4期17卷 3130-3138页

作者： Zedong Hu Juanjuan Lu Hongyi Dou Jianan Shen James PBarnard juncheng liu Xinghang Zhang Haiyan Wang School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47906USA School of Materials Engineering Purdue UniversityWest LafayetteIN 47906USA

Oxide-metal based nanocomposite thin films have attracted great interests owing to their unique anisotropic structure and physical properties.A wide range of Au-based oxide-metal nanocomposites have been demonstrated,while other metal systems are scarce due to the challenges in the initial nucleation and growth as well as possible interdiffusions of the metallic nanopillars.In this work,a unique anodic aluminum oxide(AAO)template was used to grow a thin Co seed layer and the following self-assembled metal-oxide(Co-BaTiO_(3))vertically aligned nanocomposite thin film layer.The AAO template allows the uniform growth of Co-seeds and successfully deposition of highly ordered Co pillars(with diameter<5 nm and interval between pillars<10 nm)inside the oxide matrix.Significant magnetic anisotropy and strong magneto-optical coupling properties have been observed.A thin Au-BaTiO_(3) template was also later introduced for further enhanced nucleation and ordered growth of the Co-nanopillars.Taking the advantage of such a unique nanostructure,a large out-of-plane(OP)coercive field(Hc)of~5000 Oe has been achieved,making the nanocomposite an ideal candidate for high density perpendicular magnetic tunneling junction(p-MTJ).A strong polar magneto-optical Kerr effect(MOKE)has also been observed which inspires a novel optical-based reading method of the MTJ states.

关键词： vertically aligned nanocomposite(VAN) Co BaTiO_(3) thin film magneto-optical coupling magnetic anisotropy

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 lacking.We investigated the microplastic pollution levels in wet sediments collected from the Three Gorges Reservoir,the largest reservoir of China.Results 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 attention.Fibrous microplastics were the most abundant type of microplastic particles in reservoir sediments,whereas polystyrene,polypropylene,and polyamide were the main types of polymers.The apparent spatial heterogeneity in morphology and color of microplastics is attributed to different anthropogenic or landbased pollution sources.Moreover,the accumulation of microplastics near the inlet of tributaries reflects the role of potential contributors of tributaries.More 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 pollutants.Therefore,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

Mechanistic insights into the processes of the initial stage of electrolyte degradation in lithium metal batteries

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Chinese Chemical Letters 2024年第3期35卷 473-478页

作者： Yao Wang juncheng Wang Jianwei Nai Jianmin Luo Xinyong Tao Yujing liu College of Materials Science and Engineering Zhejiang University of TechnologyHangzhou 310014China Moganshan Research Institute at Deqing County Zhejiang University of Technology Huzhou 313000China

The lithium(Li)metal batteries(LMBs)are considered one of the most promising next-generation batteries due to its extremely high theoretical specific capacity.However,there are a couple of issues,e.g.,the serious side reactions that occurred at the solid-liquid interface between the electrolyte and Li metal anode,hindering the broad commercialization of LMBs.Thus,a comprehensive understanding of the mechanisms underlying the decomposition of electrolytes is crucial to the design of LMBs.Herein,we utilize density functional theory simulations to explore the decomposition mechanism of electrolytes.The most commonly used ether electrolyte solvents,i.e.,1,2-dimethoxyethane(DME)and 1,3-dioxalane(DOL),based on suitable lithium salts,namely bis(trifluoromethanesulfonyl)imide(LiTFSI),are chosen to model the actual situations.We explicitly demonstrate that an electron-rich environment near the interface accelerates the decomposition of electrolytes.For ether electrolytes,we show that the LiTFSI degradation path is depending on the ratio of DOL to DME.In addition,the solvation structures of lithium-ion undergo a series of transformations upon electrolyte degradation,becoming thermodynamically more favorable and having a higher reduction potential in an electron-rich environment.Our finding provides new insights into the decomposition mechanisms of electrolytes and paves the way for the rational design of high-performance LMBs.

关键词： Li metal battery Electrolyte Solvation structures Interface Density functional theory

Identifying coronary artery bypass grafting patients at high risk for adverse long-term prognosis using serial health-related quality of life assessments

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中华医学杂志(英文版) 2024年第9期137卷 1069-1077页

作者： Wang juncheng liu Hanning Yue Chao Yang Limeng Yang Kai Zhao Yan Ren Huan Zhang Ying Zheng Zhe National Clinical Research Center for Cardiovascular Diseases State Key Laboratory of Cardiovascular Disease Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Cardiovascular Surgery Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Vascular Surgery Fuwai Hospital National Center for Cardiovascular Diseases Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China Department of Cardiac Surgery Wuhan Asia Heart Hospital Wuhan Hubei China

Background: Patients who undergo coronary artery bypass grafting (CABG) are known to be at a significant risk of experiencing long-term adverse events, emphasizing the importance of regular assessments. Evaluating health-related quality of life (HRQoL) serves as a direct method to gauge prognosis. Our objective is to ascertain the prognostic significance of consecutive HRQoL assessments using the Physical Component Summary (PCS) and Mental Component Summary (MCS) derived from the Short-Form 36 (SF-36) health survey in CABG patients.Methods: The study population consisted of 433 patients who underwent isolated elective CABG at Fuwai Hospital between 2012 and 2013. SF-36 assessments were conducted during both the hospitalization period and follow-up. The primary endpoint of the study was all-cause mortality, while the secondary outcome was a composite measure including death, myocardial infarction, stroke, and repeat revascularization. We assessed the relationships between the PCS and MCS at baseline, as well as their changes during the first 6 months after the surgery (referred to as ΔPCS and ΔMCS, respectively), and the observed outcomes.Results: The patients were followed for an average of 6.28 years, during which 35 individuals (35/433, 8.1%) died. After adjusting for clinical variables, it was observed that baseline MCS scores (hazard ratio [HR] for a 1-standard deviation [SD] decrease, 1.57; 95% confidence interval [CI], 1.07–2.30) and ΔMCS (HR for a 1-SD decrease, 1.67; 95% CI, 1.09–2.56) were associated with all-cause mortality. However, baseline PCS scores and ΔPCS did not exhibit a significant relationship with all-cause mortality. Notably, there was a dose-response relationship observed between ΔMCS and the likelihood of all-cause mortality (HRs for the 2nd, 3rd and 4th quartiles compared to the 1st quartile, 0.33, 0.45 and 0.11, respectively).Conclusions: Baseline MCS and changes in MCS were independent predictors for long-term mortality of CABG. Better mental health status and recovery indicated better

关键词： Coronary artery bypass grafting Coronary artery disease Prognosis Quality of life Short-Form 36 Risk factor Serial measurements

Bi-doped carbon quantum dots functionalized liposomes with fluorescence visualization imaging for tumor diagnosis and treatment

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Chinese Chemical Letters 2024年第4期35卷 414-419页

作者： Peide Zhu Yangjia liu Yaoyao Tang Siqi Zhu Xinyang liu Lei Yin Quan liu Zhiqiang Yu Quan Xu Dixian Luo juncheng Wang State Key Laboratory of Heavy Oil Processing China University of Petroleum-BeijingBeijing 102249China Department of Laboratory Medicine Dongguan Institute of Clinical Cancer ResearchAffiliated Dongguan HospitalSouthern Medical UniversityDongguan 523058China Department of Laboratory Medicine Huazhong University of Science and Technology Union Shenzhen Hospital(Nanshan Hospital)Shenzhen 518052China Institute of Stomatology First Medical CenterChinese PLA General HospitalBeijing 100853China

Liposomes are one of the significant classes of antitumor nanomaterials and the most successful nanomedicine drugs in clinical translation. However, it is difficult to accurately reveal liposome delivery modes and drug release rates at different p H values to assess the biodistribution and drug delivery pathways in vivo. Here, we established a strategy to integrate Bi-doped carbon quantum dots(CQDs)with liposomes to produce fluorescence visualization and therapeutic effects, namely lipo/Bi-doped CQDs.Lipo/Bi-doped CQDs show good water solubility and physicochemical properties, which can be used for in vitro labeling of colon cancer(CT26) cells and in vivo imaging localization tracking tumors for monitoring. Simultaneously, thanks to the excellent p H sensitivity and ion doping characteristic of Bi-doped CQDs, lipo/Bi-doped CQDs can be used to reveal the drug release rate of liposomes at different p H values and exhibit potential effects in vivo antitumor therapy.

关键词： Bi-doped CQDs Lipo/Bi-doped CQDs pH sensitivity In vitro/in vivo imaging Diagnosis and treatment integration

The influence of bioturbation on sandy reservoirs: the delta front sand of the lower Zhujiang Formation, Baiyun Depression, Zhujiang River Mouth Basin

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Acta Oceanologica Sinica 2023年第9期42卷 27-43页

作者： Zhifeng Xing Wei Wu juncheng liu Yongan Qi Wei Zheng The Institute of Resources and Environment Henan Polytechnic UniversityJiaozuo 454000China Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Mineral Shandong University of Science and TechnologyQingdao 266590China

Ichnofossils are well developed in clastic rock reservoirs in marine and transitional facies, which can considerably change the physical properties of the reservoir. However, this influence is not well understood, raising an important problem in the effective development of petroleum reservoirs. This paper analyzes continental shelf margin delta reservoirs through core observation, cast thin section observation and reservoir physical property test. Some important scientific insights are obtained:(1) The presence of Cruziana ichnofacies, including Asterosoma, Ophiomorpha, Planolites, Skolithos, Thalassinoides, and other ichnofossils can be used to identify in subaqueous distributary channels, subaqueous levee, frontal sheet sand, abandoned river channels, crevasse channels, main channels and channel mouth bars. Considerable differences in the types of ichnofossils and the degree of bioturbation can be observed in the different petrofacies.(2) Ichnofossils and bioturbation play a complex role in controlling reservoir properties. The reservoir physical properties have the characteristics of a decrease–increase–decrease curve with increasing bioturbation degree. This complex change is controlled by the sediment mixing and packing of bioturbation and the diagenetic environment controlled by the ichnofossils.(3) Sea-level cycle changes affect the modification of the reservoir through sediment packing. Bioturbation weakens the reservoir's physical property when sea level slowly rises and improves the reservoir's physical property when base level slowly falls.

关键词： bioturbation reservoir physical properties sedimentary petrofacies shelf margin delta Baiyun Sag

Directional emissions from perovskite nanocrystals thin film enabled by metasurface integration through one step spin-coating process

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Nano Research 2023年第5期16卷 7646-7653页

作者： Kexue Li Xuanyu Zhang Peinan Ni juncheng liu Fengyuan Lin Xu Man Wenfeng Cai Jianxun liu Yanjun liu Rui Chen Zhipeng Wei State Key Laboratory of High Power Semiconductor Laser School of physicsChangchun University of Science and TechnologyChangchun 130022China Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China Photonics Laboratory Department of Microtechnology and NanoscienceChalmers University of TechnologyGöteborgSE-41296Sweden

Advances in thin film light-emitting devices have fueled the rapid growth of a new class of solid-state lighting devices,featuring low fabrication cost,high quantum efficiency,broadband spectrum coverage,etc.In contrast to the conventional inorganic semiconductors that rely on lattice matched high crystalline quality substrate,solution processable thin films eliminate the dependence on the substrate,which is highly desired for the ease and versatility of integrations with foreign medium.By taking this advantage,this work developed an ultracompact solution to control the directionality of thin film emitters using integrated dielectric metasurface through one step spin-coating process.As a proof of concept,directional emissions from perovskite nanocrystal thin film,including collimated light emissions and two-dimensional beam steering,are experimentally demonstrated.Notably,our approach,where light emitters were integrated on the back side of substrate after the fabrication of metasurface,judiciously avoids any potential degradation of material optical quality caused by the multi-step nanofabrication.Therefore,it can serve as a generalized scheme to engage the advantageous properties of dielectric metasurface,including the compactness,high efficiency,beam controllability with the emerging thin film light-emitting diodes(LEDs),which is applicable to a wide range of solution processable materials,including organic light-emitting diodes,quantum-dot light emitting diodes,polymer LEDs,and perovskite LEDs,opening up new pathways to develop low-cost and ultra-compact solid state light sources with versatile beams characteristics.

关键词： solid state light source perovskite light-emitting diodes(LEDs) metasurface integrations on-chip beam shaping beam steering

High-rate CH_(4)-to-C_(2)H_(6) photoconversion enabled by Au/ZnO porous nanosheets under oxygen-free system

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Science China Chemistry 2024年第3期67卷 869-875页

作者： Kai Zheng Xiaojing Zhang Jun Hu Chengbin Xu juncheng Zhu Jing Li Mingyu Wu Shan Zhu Li Li Shumin Wang Yumei Lv Xin He Ming Zuo Chengyuan liu Yang Pan Junfa Zhu Yongfu Sun Yi Xie Hefei National Laboratory for Physical Sciences at Microscale National Synchrotron Radiation LaboratoryUniversity of Science and Technology of ChinaHefei 230026China Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China State Grid Anhui Electric Power Research Institute Hefei 230601China

Photocatalytic CH_(4) coupling into high-valued C_(2)H_(6) is highly attractive,whereas the photosynthetic rate,especially under oxygen-free system,is still unsatisfying.Here,we designed the negatively charged metal supported on metal oxide nanosheets to activate the inert C-H bond in CH_(4)and hence accelerate CH_(4) coupling performance.As an example,the synthetic Au/ZnO porous nanosheets exhibit the C_(2)H_(6) photosynthetic rate of 1,121.6μmol g^(-1)_(cat)h^(-1)and the CH_(4) conversion rate of 2,374.6μmol g^(-1)_(cat)h^(-1) under oxygen-free system,2 orders of magnitude higher than those of previously reported photocatalysts.By virtue of several in situ spectroscopic techniques,it is established that the generated Au^(δ-)and O^-species together polarized the C-H bond,while the Au^(δ-)and O^-species jointly stabilized the CH_(3) intermediates,which favored the coupling of CH_(3) intermediate to photosynthesize C_(2)H_(6) instead of overoxidation into CO_(x).Thus,the design of dual active species is beneficial for achieving high-efficient CH_(4)-to-C_(2)H_(6) photoconversion.

关键词： dual surface-active sites selective methane coupling ethane room temperature

用于农产品冷链物流需求预测的GRA-WHO-TCN组合模型

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智慧农业（中英文） 2024年第3期6卷 148-158页

作者：刘艳季俊成深圳信息职业技术学院财经学院广东深圳518000 澳门理工大学应用科学院中国澳门特别行政区999078

[目的/意义]为了解决冷链物流需求预测在数字化转型中存在特征提取不充分、数据非线性程度高和算法易陷入局部最优等问题,提出一种结合灰色关联分析(Grey Relational Analysis,GRA)、野马优化算法(Wild Horse Optimizer,WHO)和时序卷积... 详细信息

[目的/意义]为了解决冷链物流需求预测在数字化转型中存在特征提取不充分、数据非线性程度高和算法易陷入局部最优等问题,提出一种结合灰色关联分析(Grey Relational Analysis,GRA)、野马优化算法(Wild Horse Optimizer,WHO)和时序卷积网络(Temporal Convolutional Networks,TCN)的组合预测模型,旨在解决需求预测精度不高的问题,以实现农产品供应链智能化管理。[方法]首先运用GRA对农产品冷链物流相关指标进行关联度筛选;其次采用TCN充分考虑农产品供应链中社会经济数据及物流信息中的时序性特征,并使用WHO对TCN模型超参数进行寻优;最后运用优化的GRA-WHO-TCN模型对浙江省冷链物流需求进行预测。[结果和讨论]采用WHO的时序算法TCN模型能够有效提取多维度数据的时序特征和空间特征,具备较好的拟合效果。与GRALSTM、GRA-TCN和GRA-WHO-LSTM模型相比,GRA-WHO-TCN冷链物流需求预测模型具有较低的均方根误差值(11.3)和有效的相关系数(0.95),且预测2016—2020年浙江省农产品冷链物流需求量分别为2980、3046、2487、2645和2799万吨,能够实现对冷链物流需求较高的预测精度。[结论]提出的GRA-WHO-TCN模型具备良好的优化和预测能力,能够为数字经济背景下农产品供应链物资流、信息流发展提供科学预测依据和实际参考价值。

关键词：数字化转型农产品供应链冷链物流灰色关联分析野马优化算法时序卷积网络

我国中老年人群慢性病患病率及患病种类区域差异与医疗卫生资源的相关性研究

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中国全科医学 2024年第12期27卷 1452-1459页

作者：刘影姜俊丞景汇泉首都医科大学公共卫生学院北京市100069 北京中关村信息谷科技服务部北京市100086

背景中国正逐渐步入老龄化社会,中老年人的健康问题越来越受到关注,其中高血压、糖尿病、冠心病、脑卒中等慢性病成为主要的健康威胁。同时,医疗卫生资源分布不均,导致地区间的医疗水平和服务质量存在差异。目的探讨我国中老年人群慢性... 详细信息

背景中国正逐渐步入老龄化社会,中老年人的健康问题越来越受到关注,其中高血压、糖尿病、冠心病、脑卒中等慢性病成为主要的健康威胁。同时,医疗卫生资源分布不均,导致地区间的医疗水平和服务质量存在差异。目的探讨我国中老年人群慢性病患病率、患病种类区域差异与医疗卫生资源的相关性。方法2022年10月—2023年3月研究者通过对中国健康与养老追踪调查2018年(CHARLS)数据进行清洗、整理及统计分析,共纳入19520名≥45岁的中老年人,并选取《中国卫生统计年鉴》(2011—2020年)中的2018年统计数据作为对应的医疗卫生资源相关数据。采用多元线性回归分析的方法将各省份的床位数、卫生技术人员数[执业(助理)医师、注册护士、乡村医生和卫生员]、财政支出(卫生健康总支出)、卫生机构数(医院、基层医疗卫生机构、专业公共卫生机构)的泰尔指数与各省份中老年人慢性病患病率进行相关性分析。结果东、中、西部地区中老年人慢性病患病率(χ^(2)=57.900,P<0.001)、患慢性病数量(χ^(2)=11.138,P=0.004)比较,差异有统计学意义;东、中、西部慢性地区中老年人在14种慢性病患病类型中,慢性肺部疾病(χ^(2)=30.906,P<0.001)、肝脏疾病(χ^(2)=17.871,P<0.001)、脑血管疾病(χ^(2)=18.313,P<0.001)、肾脏疾病(χ^(2)=24.383,P<0.001)、消化系统疾病(χ^(2)=16.973,P<0.001)、记忆相关疾病(χ^(2)=6.898,P=0.032)、哮喘(χ^(2)=22.055,P<0.001)的患病率比较,差异有统计学意义;多元线性回归分析结果显示,中老年人慢性病总体患病状况与医院、基层医疗机构、执业(助理)医师、注册护士、乡村医生和卫生财政支出的公平性有关(P<0.05)。结论我国东、中、西部中老年人群慢性病患病率存在区域差异,不同地区对卫生事业的投入及医疗卫生资源配置也存在一定差异。应加强重大慢性病的区域性健康管理,提高基层防病治病和健康管理能力,壮大医疗卫生人员队伍,改善医疗卫生资源区域配置公平性,从而缩短东、中、西部中老年人慢性病患病的区域差异。

关键词：慢性病中老年人区域差异医疗卫生资源泰尔指数相关性