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Design of a polarization splitter for an ultra-broadband dual-core photonic crystal fiber 被引量:1
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作者 yongtao li Jiesong Deng +2 位作者 Zhen Yang Hui Zou Yuzhou Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第5期407-415,共9页
A novel ultra-broadband polarization splitter based on a dual-core photonic crystal fiber(DC-PCF)is designed.The full-vector finite element method and coupled-mode theory are employed to investigate the characteristic... A novel ultra-broadband polarization splitter based on a dual-core photonic crystal fiber(DC-PCF)is designed.The full-vector finite element method and coupled-mode theory are employed to investigate the characteristics of the polarization splitter.According to the numerical results,a graphene-filled layer not only broadens the working bandwidth but also reduces the size of the polarization splitter.Furthermore,the fluorine-doped region and the germanium-doped region can broaden the bandwidth.Also,the 4.78 mm long polarization splitter can achieve an extinction ratio of-98.6 d B at a wavelength of 1550 nm.When extinction ratio is less than-20 d B,the range of the wavelength is 1027 nm-1723 nm with a bandwidth of 696 nm.Overall,the polarization splitter can be applied to all-optical network communication systems in the infrared and near-infrared wavelength range. 展开更多
关键词 photonic crystal fiber polarization splitter broadband bandwidth extinction ratio
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Clinical Application of Lobaplatin Combined with Docetaxel in Adjuvant Chemotherapy for Triple-Negative Breast Cancer in Elderly Patients 被引量:1
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作者 Weihua Jiang li Wang +3 位作者 yongtao li Chenguang Zhang lina Yi Jianghua Ou 《Advances in Modern Oncology Research》 2020年第1期9-13,共5页
To investigate the adverse reactions and efficacy of docetaxel combined with lobaplatin in adjuvant chemotherapy for triple-negative breast cancer in elderly patients.A total of 96 elderly triple-negative breast cance... To investigate the adverse reactions and efficacy of docetaxel combined with lobaplatin in adjuvant chemotherapy for triple-negative breast cancer in elderly patients.A total of 96 elderly triple-negative breast cancer patients admitted to our hospital from January 2008 to December 2011 were randomly divided into two groups.A group of 56 patients received docetaxel 75 mg·m^(-2),intravenous drip,d1;lobaplatin 30 mg·m^(-2),intravenous drip,d1;21 days repeat,a total of 6 cycles.A group of 40 patients received chemotherapy for 6 cycles with an anthracycline-containing(TEC)regimen.Comparison of adverse reactions and 5-year diseasefree survival in both groups.The incidence of thrombocytopenia was significantly higher in 56 patients with TL regimen than those with TCE-containing anthracyclines(P=0.005).But the incidence of cardiotoxicity was 32.5%in the TEC group.And the difference was statistically significant(P=0.008).The 5-year disease-free survival rate was 73.2%in the TL group and 67.5%in the TEC group.There was no statistical difference.Docetaxel combined with lobaplatin in the treatment of elderly triple-negative breast cancer has no significant difference in efficacy compared with traditional anthracycline-containing drugs,but it can avoid the cardiotoxicity caused by anthracyclines.It’s a new option for elderly TNBC adjuvant chemotherapy,suggesting to expand the sample content for further research. 展开更多
关键词 DOCETAXEL Lobaplatin Triple-negative breast cancer
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Anion-Regulated Weakly Solvating Electrolytes for High-Voltage Lithium Metal Batteries
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作者 Zhipeng Jiang Jisheng Mo +5 位作者 Chen li Haiwen li Qingan Zhang Ziqi Zeng Jia Xie yongtao li 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第6期259-265,共7页
Development of advanced high-voltage electrolytes is key to achieving high-energy-density lithium metal batteries(LMBs).Weakly solvating electrolytes(WSE)can produce unique anion-driven interphasial chemistry via alte... Development of advanced high-voltage electrolytes is key to achieving high-energy-density lithium metal batteries(LMBs).Weakly solvating electrolytes(WSE)can produce unique anion-driven interphasial chemistry via altering the solvating power of the solvent,but it is difficult to dissolve the majority of Li salts and fail to cycle at a cut-off voltage above 4.5 V.Herein,we present a new-type WSE that is regulated by the anion rather than the solvent,and the first realize stable cycling of dimethoxyethane(DME)at 4.6 V without the use of the“solvent-in-salt”strategy.The relationships between the degree of dissociation of salts,the solvation structure of electrolytes,and the electrochemical performance of LMBs were systematically investigated.We found that LiBF_(4),which has the lowest degree of dissociation,can construct an anion-rich inner solvation shell,resulting in anion-derived anode/cathode interphases.Thanks to such unusual solvation structure and interphasial chemistry,the Li-LiCoO_(2)full cell with LiBF_(4)-based WSE could deliver excellent rate performance(115 mAh g^(-1)at 10 C)and outstanding cycling stability even under practical conditions,including high loading(10.7 mg cm^(-2)),thin Li(50μm),and limited electrolyte(1.2μL mg^(-1)). 展开更多
关键词 high-voltage LiCoO_(2) lithium metal batteries solvation structure weakly solvating electrolyte
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A Localized-Statistic-Based Approach for Biomarker Identification of Omics Data
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作者 Kuan Zhang He Chen yongtao li 《Engineering(科研)》 2013年第10期433-439,共7页
Omics data provides an essential means for molecular biology and systems biology to capture the systematic properties of inner activities of cells. And one of the strongest challenge problems biological researchers ha... Omics data provides an essential means for molecular biology and systems biology to capture the systematic properties of inner activities of cells. And one of the strongest challenge problems biological researchers have faced is to find the methods for discovering biomarkers for tracking the process of disease such as cancer. So some feature selection methods have been widely used to cope with discovering biomarkers problem. However omics data usually contains a large number of features, but a small number of samples and some omics data have a large range distribution, which make feature selection methods remains difficult to deal with omics data. In order to overcome the problems, wepresent a computing method called localized statistic of abundance distribution based on Gaussian window(LSADBGW) to test the significance of the feature. The experiments on three datasets including gene and protein datasets showed the accuracy and efficiency of LSADBGW for feature selection. 展开更多
关键词 Protein-Omics DATA BIOMARKER Selection LOCALIZED Statistic GAUSSIAN WINDOW
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行政分权、财政分权与中国经济增长——来自县级证据
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作者 李永涛 陈硕 彭耀辉 《经济学报》 CSSCI 2024年第3期363-393,共31页
对改革开放以来我国取得的经济成就,现有文献主要围绕财政分权展开。除了财政分权,我国央地关系的调整也包括管理权下放,即行政分权。虽然改革开放后已积累了非常多行政分权实践,但致力于检验其作用的研究并不丰富。本文试图在一个统一... 对改革开放以来我国取得的经济成就,现有文献主要围绕财政分权展开。除了财政分权,我国央地关系的调整也包括管理权下放,即行政分权。虽然改革开放后已积累了非常多行政分权实践,但致力于检验其作用的研究并不丰富。本文试图在一个统一框架下检验两种分权方式对经济增长的作用。基于2000—2010年间“扩权强县”改革样本并采用空间配比和双重差分方法,我们发现“扩权强县”改革能够显著促进县域经济增长。具体而言,在整个改革期间行政分权可以解释当地实际GDP增长的3%~5%。就作用机制来说,行政分权主要是通过扩大地方基本建设支出及提高财政支出效率来实现对经济的推动作用。 展开更多
关键词 行政分权 财政分权 经济增长
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Synergy of inside doped metals–Outside coated graphene to enhance hydrogen storage in magnesium-based alloys
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作者 Kun Zhang Yu Chang +7 位作者 Jingjing Lei Jing Chen Tingzhi Si Xiaoli Ding Ping Cui Hai-Wen li Qingan Zhang yongtao li 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第6期2462-2471,共10页
Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption cycles.To solve this problem,herein we propose a novel method ... Grain growth of magnesium(Mg)and its hydride is one of the main reasons for kinetic and capacity degradation during the hydrogen absorption and desorption cycles.To solve this problem,herein we propose a novel method involving synergistic effect of inside embedded metals and outside coated graphene to limit the growth of Mg and its hydride grains.The graphene coated Mg-Y-Al alloys were selected as a model system for demonstrating this positive effect where the Mg_(91)Y_(3)Al_(6)alloy was first prepared by rapidly solidified method and then high-pressure milled with 5 wt%graphene upon 5 MPa hydrogen gas for obtaining in-situ formed YAl_(2)and YH_(3)embedded in the MgH_(2)matrix with graphene shell(denoted as MgH_(2)-Y-Al@GR).In comparison to pure MgH_(2),the obtained MgH_(2)-Y-Al@GR composites deliver much better kinetics and more stable cyclic performance.For instance,the MgH_(2)-Y-Al@GR can release about 6.1 wt%H_(2)within 30 min at 300℃ but pure MgH_(2)only desorbs∼1.5 wt%H_(2).The activation energy for desorption of MgH_(2)-Y-Al@GR samples is calculated to be 75.3±9.1 kJ/mol that is much lower than approximately 160 kJ/mol for pure MgH_(2).Moreover,its capacity retention is promoted from∼57%of pure MgH_(2)to∼84%after 50th cycles without obvious particle agglomeration and grain growth.The synergistic effect of outside graphene coating with inside embedded metals which could provide a huge number of active sites for catalysis as well as inhibit the grain growth of Mg and its hydride is believed to be responsible for these. 展开更多
关键词 Energy Hydrogen storage Mg alloys Synergy effect
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Defect Formation Mechanisms in Selective Laser Melting:A Review 被引量:68
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作者 Bi Zhang yongtao li Qian Bai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期515-527,共13页
Defect formation is a common problem in selective laser melting (SLM). This paper provides a review of defect formation mechanisms in SLM. It sum- marizes the recent research outcomes on defect findings and classifi... Defect formation is a common problem in selective laser melting (SLM). This paper provides a review of defect formation mechanisms in SLM. It sum- marizes the recent research outcomes on defect findings and classification, analyzes formation mechanisms of the common defects, such as porosities, incomplete fusion holes, and cracks. The paper discusses the effect of the process parameters on defect formation and the impact of defect formation on the mechanical properties of a fabri- cated part. Based on the discussion, the paper proposes strategies for defect suppression and control in SLM. 展开更多
关键词 Selective laser melting Process parameters -Defect Mechanical properties
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A Deep Learning System to Screen Novel Coronavirus Disease 2019 Pneumonia 被引量:21
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作者 Xiaowei Xu Xiangao Jiang +18 位作者 Chunlian Ma Peng Du Xukun li Shuangzhi Lv liang Yu Qin Ni Yanfei Chen Junwei Su Guanjing Lang yongtao li Hong Zhao Jun liu Kaijin Xu lingxiang Ruan Jifang Sheng Yunqing Qiu Wei Wu Tingbo liang Lanjuan li 《Engineering》 SCIE EI 2020年第10期1266-1274,共9页
实时逆转录聚合酶链反应(RT-PCR)检测早期新冠病毒肺炎(COVID-19)患者的痰液或鼻咽拭子中的病毒RNA阳性率较低。同时,COVID-19的计算机断层扫描(CT)影像学的临床表现有其自身的特点,不同于甲型流感病毒性肺炎(IAVP)等其他类型的病毒性... 实时逆转录聚合酶链反应(RT-PCR)检测早期新冠病毒肺炎(COVID-19)患者的痰液或鼻咽拭子中的病毒RNA阳性率较低。同时,COVID-19的计算机断层扫描(CT)影像学的临床表现有其自身的特点,不同于甲型流感病毒性肺炎(IAVP)等其他类型的病毒性肺炎。本研究旨在应用深度学习技术,建立COVID-19、IAVP及健康人群肺部CT的早期筛查模型。本研究共采集618份CT样本,其中219份样本来自110例COVID-19患者(平均年龄50岁,其中男性63例,占57.3%),224份样本来自224例IAVP患者(平均年龄61岁,其中男性156例,占69.6%),175份样本来自健康人群(平均年龄39岁,其中男性97例,占55.4%)。所有CT样本均来自浙江省三家COVID-19定点收治医院。我们首先利用胸部CT图像集的三维(3D)深度学习模型分割出候选感染区域,然后利用位置敏感机制深度学习网络将这些分离的图像归类为COVID-19、IAVP以及与感染无关(ITI)的图像,并且输出相应置信度得分。最后,用Noisy-OR贝叶斯函数计算每份CT病例的感染类型及总置信度。测试数据集的实验结果表明,从整体CT病例来看,本研究利用深度学习系统建立的COVID-19患者的早期筛查模型的总体准确率为86.7%。该模型有望成为一线临床医生诊断COVID-19的一种有效的辅助方法。 展开更多
关键词 COVID-19 位置敏感机制深度学习网络 计算机断层扫描
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Energy partitioning and evapotranspiration in a black locust plantation on the Yellow River Delta,China 被引量:2
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作者 Xiang Gao Zhenyu Du +8 位作者 Qingshan Yang Jinsong Zhang yongtao li Xiaojie Wang Fengxue Gu Weiping Hao Zekun Yang Dexi liu Jianmin Chu 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第4期1219-1232,共14页
Plantations of woody tree species play a crucial role in ecological security along coastal zones.Understanding energy partitioning and evapotranspiration can reveal land–atmosphere interaction processes.We investigat... Plantations of woody tree species play a crucial role in ecological security along coastal zones.Understanding energy partitioning and evapotranspiration can reveal land–atmosphere interaction processes.We investigated energy fluxes,evapotranspiration,and their related biophysical factors using eddy covariance techniques in a black locust(Robinia pseudoacacia L.)plantation in 2016,2018,and 2019 on the Yellow River Delta.Downward longwave radiation offsets 84–85%of upward longwave radiation;upward shortwave radiation accounted for 12–13%of downward shortwave radiation.The ratio of net radiation to downward radiation was 18–19%over the three years.During the growing season,latent heat flux was the largest component of net radiation;during the dormant season,the sensible heat flux was the dominant component of net radiation.The seasonal variation in daily evapotranspiration was mainly controlled by net radiation,air temperature,vapor pressure deficit,and leaf area index.Black locust phenology influenced daily evapotranspiration variations,and evapotranspiration was greater under sea winds than under land winds because soil water content at 10-cm depth was greater under sea winds during the day.Seasonal patterns of daily evaporative fraction,Bowen ratio,crop coefficient,Priestley–Taylor coefficient,surface conductance,and decoupling coefficient were mainly controlled by leaf area index.The threshold value of daily surface conductance was approximately 8 mm sover the plantation. 展开更多
关键词 Black locust plantation Yellow River Delta Eddy covariance Energy partitioning EVAPOTRANSPIRATION
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宁夏教师信息素养规模化测评与发展路径研究 被引量:1
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作者 李永涛 饶小李 《中国教育信息化》 2023年第5期87-94,共8页
推进大规模、持续性、多角色的区域中小学教师信息素养监测评价,有利于全景管理、精准诊断与科学决策。宁夏回族自治区特别重视全区教师信息素养的全面培育与引领示范,从2020年开始在全国率先以省为单位对全区的校长、教研员和教师的信... 推进大规模、持续性、多角色的区域中小学教师信息素养监测评价,有利于全景管理、精准诊断与科学决策。宁夏回族自治区特别重视全区教师信息素养的全面培育与引领示范,从2020年开始在全国率先以省为单位对全区的校长、教研员和教师的信息素养进行规模化测评。测评发现,2020年与2021年宁夏回族自治区教育信息化工作取得一定的成果和进展,但同时也存在着一些共性问题。基于此,提出相关发展建议:加强统筹领导和政策解读,提供信息化发展保障机制;加强对各类教育信息化活动统筹协调,以活动带应用;基于评估结果精准施策,关注特定教师群体的发展;加强典型案例评选和挖掘,以点带面,逐步扩大影响。 展开更多
关键词 教师信息素养 规模化测评 现状分析 提升建议
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Defined organic-octamolybdate crystalline superstructures derived Mo_(2)C@C as efficient hydrogen evolution electrocatalysts
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作者 Jiao li Chenyang Zhang +6 位作者 Chuhan Wu Yan liu Xuejian Zhang Xiao li yongtao li Jing Sun Zhongmin Su 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第6期201-205,共5页
Hydrogen evolution electrocatalysts derived from metal-organic crystalline frameworks can inherit the merits of ordered and adjustable structures with high surface area.In this paper,organic-octamolybdate crystalline ... Hydrogen evolution electrocatalysts derived from metal-organic crystalline frameworks can inherit the merits of ordered and adjustable structures with high surface area.In this paper,organic-octamolybdate crystalline superstructures(OOCS)with a fixed stoichiometric ratio of Mo_(8)(L)_(2) and high Mo content(>40 wt%)were synthesized using flexible ligands with controllable lengths(named as OOCS-1-3).Then,molybdenum carbides coated with carbon layers as electrocatalysts(Mo_(2)C@C-1-3)can be obtained directly from a one-step high-temperature carbonization process using OOCS-1-3 as precursors.As a typical example,Mo_(2)C@C-3 exhibits satisfactory hydrogen evolution activity with a low overpotential of 151 m V(1.0 mol/L KOH)at 10 m A/cm^(2) and stability for 24 h.The electrocatalytic activity is mainly from the synergistic interactions between the carbon layers and molybdenum carbide species.Furthermore,compared with the initial content of C,N,Mo in OOCS and Mo_(2)C@C,the catalytic activity increases with the N amount.This work makes organic-octamolybdate crystalline superstructures used as general precursors to product high Mo content electrocatalysts applied in energy storage and conversion fields. 展开更多
关键词 Molybdenum carbides ELECTROCATALYSTS Organic-octamolybdate crystalline SUPERSTRUCTURES Synergistic interactions Hydrogen evolution reaction(HER)
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sp^(2) to sp^(3) hybridization transformation in 2D metal-semiconductor contact interface suppresses tunneling barrier and Fermi level pinning simultaneously
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作者 Wenchao Shan Anqi Shi +4 位作者 Zhuorong Zhong Xiuyun Zhang Bing Wang yongtao li Xianghong Niu 《Nano Research》 SCIE EI CSCD 2024年第11期10227-10234,共8页
Van der Waals (vdWs) stacking of two-dimensional (2D) materials can effectively weaken the Fermi level pinning (FLP) effect in metal/semiconductor contacts due to dangling-bond-free surfaces. However, the inherent vdW... Van der Waals (vdWs) stacking of two-dimensional (2D) materials can effectively weaken the Fermi level pinning (FLP) effect in metal/semiconductor contacts due to dangling-bond-free surfaces. However, the inherent vdWs gap always induces a considerable tunneling barrier, significantly limiting carrier injection. Herein, by inducing a sp^(2) to sp^(3) hybridization transformation in 2D carbon-based metal via surface defect engineering, the large orbital overlap can form an efficient carrier channel, overcoming the tunneling barrier. Specifically, by selecting the 2D carbon-based X_(3)C_(2) (X = Cd, Hg, and Zn) metal and the 2D MSi_(2)N_(4) (M = Cr, Hf, Mo, Ti, V, and Zr) semiconductor, we constructed 36 metal/semiconductor contacts. For vdWs contacts, although Ohmic contacts can be formed at the interface, the highest tunneling probability (P TB) is only 3.11%. As expected, the P TB can be significantly improved, as high as 48.73%, when MSi_(2)N_(4), accompanied by surface nitrogen vacancies, forms an interface covalent bond with X_(3)C_(2). Simultaneously, weak FLP and Ohmic contact remain at the covalent-bond-based surface, attributing to the protection of the MSi_(2)N_(4) band-edge electronic states by the outlying Si-N sublayer. Our work provides a promising path for advancing the progress of 2D electronic and photoelectronic devices. 展开更多
关键词 two-dimensional(2D)material metal-semiconductor contacts tunneling-barrier Schottky barrier density functional theory
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Effect of water-driven changes in rice rhizosphere on Cd lability in three soils with different pH 被引量:6
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作者 Jinjin Wang Dongqin li +4 位作者 Qin Lu Yulong Zhang Huijuan Xu Xueli Wang yongtao li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第1期82-92,共11页
Pot experiments were conducted to evaluate the effect of water management,namely continuous flooding(CF),intermittent flooding(IF)and non-flooding(NF),on Cd phytoavailaility in three paddy soils that differed in p H a... Pot experiments were conducted to evaluate the effect of water management,namely continuous flooding(CF),intermittent flooding(IF)and non-flooding(NF),on Cd phytoavailaility in three paddy soils that differed in p H and in Cd concentrations.Diffusive gradients in thin films(DGT)technique was employed to monitor soil labile Cd and Fe concentrations simultaneously at three growth stages(tillering,heading and mature stage)of rice.The Cd phytoavailability were generally in the order of NF>IF>CF,and higher rice Cd(over permitted level,0.2 mg/kg)were only found in neutral and acidic soils under NF conditions.DGT measured soil labile Cd rather than total Cd was the most reliable predictor for Cd accumulation in rice.CF enhanced the formation of root plaques,which related to oxidation of large quantities of available Fe on root surfaces due to the O2 secretion of rice root.The Cd concentration in root plaques shared the same trend with DGT-Cd.Generally,root plaques would inhibit Cd uptake by rice under CF conditions,while under IF and NF conditions,root plaques act as a temporarily store of Cd,and soil labile Cd is the key factor that controls the transfer of Cd from soil to rice.The results of principle component analysis revealed that water management had the greatest effect on soil Cd lability and rice Cd in acidic soil.Thus,it is important to consider the availability of Cd and soil p H when assessing current agricultural practices of contaminated soil in China. 展开更多
关键词 Cadmium lability RHIZOSPHERE Rice Water management Root plaque DGT technique
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Association between porpoise presence and fish choruses:implications for feeding strategies and ecosystem-based conservation of the East Asian finless porpoise 被引量:2
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作者 Zhaolong CHENG yongtao li +3 位作者 Matthew Keith PINE Tao ZUO Mingxiang NIU Jun WANG 《Integrative Zoology》 SCIE CSCD 2023年第1期169-182,共14页
The associations between feeding activities and environmental variables inform animal feeding tactics that max-imize energetic gains by minimizing energy costs while maximizing feeding success.Relevant studies in aqua... The associations between feeding activities and environmental variables inform animal feeding tactics that max-imize energetic gains by minimizing energy costs while maximizing feeding success.Relevant studies in aquatic animals,particularly marine mammals,are scarce due to difficulties in the observation of feeding behaviors in aquatic environments.This data scarcity concurrently hinders ecosystem-basedfishery management in the context of small toothed-cetacean conservation.In the present study,a passive acoustic monitoring station was deployed in an East Asianfinless porpoise habitat in Laizhou Bay to investigate potential relationships between East Asianfinless porpoises and their prey.The data revealed that porpoises were acoustically present nearly every day during the survey period.Porpoise detection rates differed between spring and autumn in concert with activities offish choruses.During spring,fish choruses were present throughout the afternoon,and this was the time when porpoise vocalizations were the most frequently detected.During autumn,whenfish choruses were absent,porpoise detec-tion rates decreased,and diurnal patterns were not detected.The close association betweenfish choruses andfin-less porpoise activities implies an“eavesdropping”feeding strategy to maximize energetic gains,similar to other toothed cetaceans that are known to engage similar feeding strategies.Underwater noise pollution,particularly those maskingfish choruses,could interruptfinless porpoises’feeding success.Fisheries competing soniferousfishes withfinless porpoise could impactfinless porpoise viability through ecosystem disruption,in addition tofishing gear entanglement. 展开更多
关键词 diel pattern noise andfishery management optimal foraging theory passive acoustic monitoring
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Identification of niclosamide as a novel antiviral agent against porcine epidemic diarrhea virus infection by targeting viral internalization 被引量:1
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作者 Yue Wang Huimin Huang +8 位作者 Dongliang li Chenxu Zhao Shuai li Panpan Qin Yaqin li Xia Yang Wenjuan Du Wentao li yongtao li 《Virologica Sinica》 SCIE CAS CSCD 2023年第2期296-308,共13页
Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a reco... Porcine epidemic diarrhea virus(PEDV),an enteropathogenic coronavirus,has catastrophic impacts on the global pig industry.However,there remain no effective drugs against PEDV infection.In this study,we utilized a recombinant PEDV expressing renilla luciferase(PEDV-Rluc)to screen potential anti-PEDV agents from an FDAapproved drug library in Vero cells.Four compounds were identified that significantly decreased luciferase activity of PEDV-Rluc.Among them,niclosamide was further characterized because it exhibited the most potent antiviral activity with the highest selectivity index.It can efficiently inhibit viral RNA synthesis,protein expression and viral progeny production of classical and variant PEDV strains in a dose-dependent manner.Time of addition assay showed that niclosamide exhibited potent anti-PEDV activity when added simultaneously with or after virus infection.Furthermore,niclosamide significantly inhibited the entry stage of PEDV infection by affecting viral internalization rather than viral attachment to cells.In addition,a combination with other small molecule inhibitors of endosomal acidification enhanced the anti-PEDV effect of niclosamide in vitro.Taken together,these findings suggested that niclosamide is a novel antiviral agent that might provide a basis for the development of novel drug therapies against PEDV and other related pathogenic coronavirus infections. 展开更多
关键词 CORONAVIRUS Porcine epidemic diarrhea virus(PEDV) Niclosamide(NIC) Antiviral Virus entry ENDOCYTOSIS Host-targeted antivirals
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Determination of selected semi-volatile organic compounds in water using automated online solid-phase extraction with large-volume injection/gas chromatography/mass spectrometry 被引量:1
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作者 yongtao li Christina L.MCCARTY Ed J.GEORGE 《Frontiers of Environmental Science & Engineering》 SCIE EI CSCD 2011年第3期417-425,共9页
A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith p... A rapid,sensitive,and cost-effective analyticalmethod was developed for the analysis of selected semivolatileorganic compounds in water.The method used anautomated online solid-phase extraction technique coupledwith programmed-temperature vaporization large-volumeinjection gas chromatography/mass spectrometry.Thewater samples were extracted by using a fully automatedmobile rack system based on x-y-z robotic techniquesusing syringes and disposable 96-well extraction plates.The method was validated for the analysis of 30 semivolatileanalytes in drinking water,groundwater,andsurface water.For a sample volume of 10 mL,the linearcalibrations ranged from 0.01 or 0.05 to 2.5μg·L^(-1),and themethod detection limits were less than 0.1μg·L^(-1).For thereagent water samples fortified at 1.0μg·L^(-1)and2.0μg·L^(-1),the obtained mean absolute recoveries were70%-130%with relative standard deviations of less than20%for most analytes.For the drinking water,groundwater,and surface water samples fortified at 1.0μg·L^(-1),theobtained mean absolute recoveries were 50%-130%withrelative standard deviations of less than 20%for mostanalytes.The new method demonstrated three advantages:1)no manipulation except the fortification of surrogatestandards prior to extraction;2)significant cost reductionassociated with sample collection,shipping,storage,andpreparation;and 3)reduced exposure to hazardous solventsand other chemicals.As a result,this new automatedmethod can be used as an effective approach for screeningand/or compliance monitoring of selected semi-volatileorganic compounds in water. 展开更多
关键词 automated solid-phase extraction programmed-temperature vaporization large-volume injection gas chromatography/mass spectrometry semi-volatile organic compounds water analysis
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Stability and interaction of biochar and iron mineral nanoparticles:effect of pH,ionic strength,and dissolved organic matter 被引量:1
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作者 Yong liu Jie Ma +6 位作者 Jiaoli Gao Xingyi Chen Xiaoxue Ouyang liping Weng Haiming li Yali Chen yongtao li 《Biochar》 SCIE 2022年第1期404-418,共15页
Biochar nanoparticles(BCNPs)and iron mineral nanoparticles(IMNPs),such as ferrihydrite nanoparticles(FHNPs),magnetite nanoparticles(MTNPs),and goethite nanoparticles(GTNPs),are often combined and used in soil remediat... Biochar nanoparticles(BCNPs)and iron mineral nanoparticles(IMNPs),such as ferrihydrite nanoparticles(FHNPs),magnetite nanoparticles(MTNPs),and goethite nanoparticles(GTNPs),are often combined and used in soil remediation.However,the stability and interaction of nanoparticles under various environmental conditions have not been investigated previously.In this study,settling experiments,a semi-empirical model,the Derjaguin-Landau-Verwey-Overbeek(DLVO)theory,scanning electron microscopy(SEM)observations,and quantum chemical calculations were used to study the interaction and heteroaggregation of BCNPs and IMNPs.Settling of BCNPs-FHNPs and BCNPs-GTNPs was stable at neutral and alkaline pH(relative concentration of unsettled nanoparticles C_(res’)=0.679-0.824),whereas fast settling of BCNPs-IMNPs was observed at acidic pH(C_(res’)=0.104-0.628).By contrast,BCNPs-MTNPs consistently showed moderate settling regardless of the mass of magnetite at all pH(C_(res’)=0.423-0.673).Both humic acid(HA,10 mg L^(−1))and ionic strength(IS,10 and 100 mM)facilitated the settling of BCNPs-FHNPs and BCNPs-MTNPs systems,whereas the settling of BCNPs-GTNPs was sensitive only to IS.Fulvic acid(10 mg L^(−1))had a general stabi-lizing effect on the BCNPs-IMNPs systems.The results of SEM and quantum chemical calculations suggested that the interaction between BCNPs and FHNPs(-2755.58 kJ mol^(−1))was stronger than that between BCNPs and GTNPs(−1706.23 kJ mol^(−1))or MTNPs(−1676.73 kJ mol^(−1)).The enhancement of heteroaggregation between BCNPs and IMNPs under unfavorable conditions(acidic pH,HA,and IS)was regulated by the strength of the interaction.Therefore,the enhancement of heteroaggregation of BCNPs-FHNPs was greater than that of BCNPs-MTNPs.In the BCNPs-GTNPs system,the high concentration and elongated structure of GTNPs may contribute greatly to heteroag-gregation and settling with small interactions.Our results highlight the influence of pH,IS,and HA on the interaction between BCNPs and IMNPs.These results will be helpful in the application of BCNPs and IMNPs for soil remediation. 展开更多
关键词 BIOCHAR Iron mineral nanoparticles STABILITY DLVO Quantum chemistry
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Magnesium borohydride Mg(BH_(4))_(2) for energy applications:A review
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作者 Xiao li Yigang Yan +6 位作者 Torben R.Jensen Yaroslav Filinchuk Iurii Dovgaliuk Dmitry Chernyshov liqing He yongtao li Hai-Wen li 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2023年第30期170-179,共10页
Mg(BH_(4))_(2) with several polymorphs,known as a high capacity(14.9 wt.%)hydrogen storage material,has become more intriguing due to the recently found new functions of gas physisorption and ionic conduc-tivity.Here ... Mg(BH_(4))_(2) with several polymorphs,known as a high capacity(14.9 wt.%)hydrogen storage material,has become more intriguing due to the recently found new functions of gas physisorption and ionic conduc-tivity.Here we review the state-of-the-art on the energy related functions of Mg(BH_(4))_(2).Mg(BH_(4))_(2) tends to form the stable intermediate[B_(12)H_(12)]^(2−) when the dehydrogenation temperature is above 400℃,the strong B-B bonding of which makes the rehydrogenation condition very harsh.In contrast,lower borane intermediate[B_(3)H_(8)]2−facilitates the rehydrogenation even at a mild condition of 100℃,suggesting the possibility of reversible hydrogen storage in Mg(BH_(4))_(2).The porous polymorphγ-Mg(BH_(4))_(2) shows attrac-tive gas adsorption properties in view of its unique hydridic surface and pore shape,and potentially can be applied in hydrogen adsorption and Kr/Xe selectivity.A new diffraction-based adsorption methodology was developed to characterize adsorption thermodynamics and kinetics ofγ-Mg(BH_(4))_(2),providing a novel idea for the characterization of crystalline porous materials.Moreover,the potential of Mg(BH_(4))_(2) as an electrolyte is discussed in the last part.Mg(BH_(4))_(2)·THF/DME acts as a liquid electrolyte in Mg-batteries,while anion substituted or neutral molecule derivatives of Mg(BH_(4))_(2) can act as solid-state electrolyte. 展开更多
关键词 HYDRIDE Hydrogen storage Gas adsorption Hydrogen adsorption ELECTROLYTE
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Watering techniques and zero-valent iron biochar pH effects on As and Cd concentrations in rice rhizosphere soils,tissues and yield 被引量:11
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作者 Md Shafiqul Islam Yali Chen +6 位作者 liping Weng Jie Ma Zulqarnain Haider Khan Zhongbin liao Abdoul Salam Issiaka Abdoul Magid yongtao li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第2期144-157,共14页
Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy fields.In this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniq... Zero-valent iron amended biochar(ZVIB)has been proposed as a promising material in immobilizing heavy metals in paddy fields.In this study,the impacts of p H of ZVIB(p H 6.3 and p H 9.7)and watering management techniques(watering amount in the order of CON(control,5/72)>3/72>1-3/72>3/100>1/72,with 5/72,for example,representing irrigation given to 5 cm above soil surface in 72 hr regular interval)on As and Cd bioavailability for rice and its grain yield(Yield BR)were investigated in a pot experiment.Brown rice As(As BR)content was irrelative to the watering treatments,while significantly decreased(>50%)with the addition of both ZVIB materials.The diminutions of brown rice Cd(Cd BR)content as well as the Yield BR were highly dependent on both the soil amendment materials’p H and watering amount.Among all the watering treatments,3/72 treatment(15%less irrigation water than the CON)with ZVIB 6.3 amendment was the optimum fit for simultaneous reduction of As BR(50%)and Cd BR contents(19%)as well as for significant increment(12%)of the Yield BR.Although high pH(9.7)ZVIB application could also efficiently decrease As and Cd contents in brown rice,it might risk grain yield lost if appropriate(e.g.3/72 in our study)watering management technique was not chosen.Therefore,ZVIB would be an environmentally friendly option as an amendment material with proper selection of watering management technique to utilize As and Cd co-contaminated arable soils safely for paddy cultivation. 展开更多
关键词 Brown rice As Brown rice Cd Grain yield Paddy soils Water management Zero-valent iron biochar
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Biogas residue biochar integrated with phosphate from its ash for the effective recovery of nutrients from piggery biogas slurry 被引量:3
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作者 Zifeng Luo Hongping Wen +6 位作者 Haotian Zhang Yunliang li Xueyi Mai Yulong Zhang Jinjin Wang yongtao li Zhen Zhang 《Biochar》 SCIE 2022年第1期800-816,共17页
Magnesium ammonium phosphate(MAP)precipitation generally requires an external phosphorus source to increase the recovery of NH_(4)^(+)-N from biogas slurry.However,P-rich piggery biogas residue has been ignored as a p... Magnesium ammonium phosphate(MAP)precipitation generally requires an external phosphorus source to increase the recovery of NH_(4)^(+)-N from biogas slurry.However,P-rich piggery biogas residue has been ignored as a phosphorus source.In this study,biogas residue was carbonized into biogas residue biochar(BRC),followed by acid leaching to synthesize functionalized BRC and release PO_(4)^(3−)-P from its ash as the phosphorus source.The effects of different acids on the leaching efficiency and morphological changes of P in BRC were investigated,and NH_(4)^(+)-N and PO_(4)^(3−)-P in the biogas slurry were recovered with functionalized BRC and MAP precipitation.The results showed that oxalic acid-hydrochloric acid mixed acid could leach more than 96%of P in BRC,while weakening the inhibitory effect of Ca^(2+)on MAP precipitation.The BRC was mainly composed of inorganic P,and most nonapatite IP and apatite P(Ca_(3)(PO_(4))2)were leached during acid leaching,with the latter more easily leached.Under optimal recovery conditions,the method had a significant recovery effect on NH_(4)^(+)-N(96.4%)and PO_(4)^(3−)-P(99.3%)in biogas slurry.The recovery of NH_(4)^(+)-N and PO_(4)^(3−)-P by functionalized BRC was mainly through chemical precipitation(forming NH_(4)MgPO_(4)·H_(2)O precipitate)while bonding with-OH,C=O and C-H functional groups.The final recovery product was also a BRC-based slow-release N-P fertilizer rich in struvite.This study solved the disposal problems of P-rich biogas residue and N-rich biogas slurry while providing an innovative technology for the resource utilization of faecal sewage at pig farms. 展开更多
关键词 Biogas slurry Biogas residue biochar Phosphorus source Ammonium and phosphorus Simultaneous recovery
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