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Morphometrics of Heliolites(Tabulata) from the Late Ordovician, Yushan, Jiangxi, South China

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Acta Geologica Sinica(English Edition) 2015年第1期89卷 38-54页

作者： DAI Mingjian LIU lu LEE Dong-Jin peng Yunbiao MIAO Aisheng China University of Geosciences CNNC No.208 Geology Party Andong National University

The Upper Ordovician Xiazhen Formation in the Jiangshan-Changshan-Yushan （JCY） triangle area on the Zhejiang-Jiangxi provincial border, South China, is composed of a mixed carbonate-siliciclastic sequence representing various shallow-water platform environments. Highly diversified and abundant heliolitid coral faunas are recognized in the formation and occur over time and space in certain stratigraphic horizons and various lithofacies. Heliolites has been studied using multivariate morphometric analysis applied to differentiate species and evaluate intraspecific and interspecific variations. Ten morphological characters quantified by examination and measurement from transverse and longitudinal thin sections and statistically tested allowed selection of effective characters to discriminate species. Results of frequency histograms, correlation analysis and principle component analysis indicated that certain characters would be suitable for cluster analysis, which were performed on principle component score matrices obtained from the raw data set coordinated with coralla by all those characters. Five major clusters at a relative distance of five on the resulting dendrogram of Heliolites are regarded as morphospecies thus making valid taxa： Heliolites tashanensis Lin and Chow, 1977; Heliolites caracolica （Lin and Chow, 1977）; Heliolites columella （Lin and Chow, 1977）; Heliolites waicunensis Lin and Chow, 1977; and H. sinensis irregularis Lin and Chow, 1977. The discrimination of these morphospecies by the cluster analysis is verified by discriminant analyses and descriptive statistics.

关键词： Taxonomy tabulate corals morphometrics Ashgillian Zhejiang-Jiangxi provinces

Analysis for integrated energy system:Benchmarking methods and implementation

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Energy Internet 2024年第1期1卷 63-80页

作者： Suhan Zhang Wei Gu X‐PZhang CYChung Ruizhi Yu Shuai lu Rodrigo Palma‐Behnke School of Electrical Engineering Southeast UniversityNanjingJiangsuChina Department of Electronic Electrical and SystemsUniversity of BirminghamBirminghamUK Department of Electrical and Electronic Engineering Hong Kong Polytechnic UniversityHung HomKowloonHong KongChina Department of Electrical Engineering Energy CenterUniversity of ChileSantiagoChile

The selection of suitable models and solutions is a fundamental requirement for con-ducting energy flow analysis in integrated energy systems(IES).However,this task is challenging due to the vast number of existing models and solutions,making it difficult to comprehensively compare scholars'studies with current *** this paper,we aim to address this issue by presenting a comprehensive overview of mainstream IES models and clarifying their relationships,thereby providing guidance for scholars in selecting appro-priate ***,we introduce several widely used solvers for solving algebraic and differential equations,along with their detailed implementations in the energy flow analysis of ***,we conduct extensive testing and demonstration of these models and methods in various cases to establish benchmarking *** facilitate reproducibility,verification and comparisons,we provide open‐source access to these datasets,including system data,analysis settings and implementations of the various solvers in the mainstream *** can utilise the provided datasets to reproduce the results,verify the findings and perform comparative ***,they have the flexibility to customise these settings according to their specific requirements.

关键词： benchmarking method energy flow analysis integrated energy system mainstream model open‐source data

Evaluation of paddy soil quality in Wanchang area of Jilin City

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Global Geology 2024年

作者： LI Chao lu Jilong WEI Qiaoqiao HOU Yaru ZHAO Wei HUA Zhaofu SUN Xiaohan College of Geoexploration Science and Technology， Jilin University

In order to identify the nutrient level and environmental quality of paddy fields in Wanchang area， and to provide scientific basis and technical support for planting rice in Wanchang area， the soil geochemical survey was carried out， 30 samples were collected from paddy soil in Wanchang area， and 20 elements (indicators) were analyzed. The characterization of the elemental content of soils in the study area was carried out， and the geochemical level for soil nutrients， the geochemical level for the soil environment， and the comprehensive geochemical level of soil quality were evaluated. The results showed that the average values of K content and pH of the soil in the study area were smaller than the background values of Jilin Province， and the average values of 18 elements including N， P， Ca， S， Pb， Zn etc. were bigger than the background values of Jilin Province. The results of the evaluation of soil single element nutrient in the study area showed that the available state nutrient levels of Mn， Zn， Cu， and K increased compared with the total amounts of nutrients level， with Cu increasing the most; the available state nutrient level of N， P， B， and Mo decreased compared with the total amounts of nutrients level， with Mo decreasing the most. The comprehensive level of soil nutrients geochemistry in paddy fields was mainly Level III (medium)， accounting for 53.33%， and the low abundance level was caused by the lack of P element; the comprehensive level of soil environmental geochemistry was mainly Level I (clean)， accounting for 96.67%， with only slight pollution caused by Cd. The comprehensive geochemical level of soil quality was mainly Level II， accounting for 66.67%. Suggestions were put forward for the rational utilization of soil resources in paddy fields in the study area.

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Co-POM@MOF-derivatives with trace cobalt content for highly efficient oxygen reduction

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Chinese Chemical Letters 2022年第2期33卷 1047-1050页

作者： Yitao Song Yewang peng Shuang Yao peng Zhang Yujie Wang Jianmin Gu Tongbu lu Zhiming Zhang Institute for New Energy Materials and Low Carbon Technologies School of Materials Science&EngineeringSchool of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China State Key Laboratory of Metastable Materials Science and Technology(MMST) Yanshan UniversityQinhuangdao 066004China

A simple and effective method for constructing highly efficient oxygen reduction catalysts with trace amount of isolated cobalt was firstly developed by the pyrolysis of Co-centered polyoxometalate@metalorganic framework (Co-POM@MOF).The Co-centered polyoxometalate ([Co W_(12)O_(40)]^(6-)) was confined in the well-defined void space of ZIF-8 to achieve homogeneous dispersion of polyoxoanions,where the isolated Co centers were well surrounded by the W-O shell and ZIF-8 *** Co-POM@MOF-derived N-doping porous carbon (Co-W-NC) with trace cobalt content was facilely prepared by the pyrolysis of the Co-POM@MOF under Ar *** single dispersion of polyoxoanions in the metal-organic framework with complete separation of Co center surrounding by W-O shell and ZIF-8 framework ensures the uniform dispersion of Co atoms,confirmed by the Fourier transform extended X-ray absorption fine structure *** Co-W-NC composite catalysts exhibit high performance for oxygen reduction reactions with a half-wave potential of 0.835 V in 0.1 mol/L KOH solution with excellent durability,which is much superior to that of the control samples derived from the[PW_(12)O_(40)]@ZIF-8,and the commercial Pt/*** work highlights a new insight for constructing highly efficient catalysts via the introduction of metal-centered polyoxometalate into metal-organic framework following the high temperature treatment process.

关键词： Metal-organic framework Polyoxometalate Polyoxoanion Oxygen reduction Electrocatalysis

人参皂苷指纹图谱在山东产西洋参质量控制中的应用

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药物分析杂志 2024年第3期44卷 512-521页

作者：张燕停陆雨顺张悦任利鹏魏晓明孙印石中国农业科学院特产研究所长春130112 山东省威海市文登区农业农村局威海264400

目的:利用超高效液相色谱-二极管阵列检测器(UPLC-PDA)法建立山东产西洋参皂苷类成分的指纹图谱,并同时测定16个单体皂苷的含量。方法:采用Acquity UPLC BEH C_(18)(50 mm×2.1 mm,1.7μm)色谱柱,以水-乙腈为流动相进行梯度洗脱,流速0.4... 详细信息

目的:利用超高效液相色谱-二极管阵列检测器(UPLC-PDA)法建立山东产西洋参皂苷类成分的指纹图谱,并同时测定16个单体皂苷的含量。方法:采用Acquity UPLC BEH C_(18)(50 mm×2.1 mm,1.7μm)色谱柱,以水-乙腈为流动相进行梯度洗脱,流速0.4 mL·min^(-1),检测波长203 nm,柱温30℃,进样量2μL。运用《中国药典》“中药色谱指纹图谱相似度评价系统(2012版)”进行评价,结合聚类分析和主成分分析对42批不同产地的西洋参进行比较。结果:山东产西洋参中16个单体皂苷总量为19.73~58.07 mg·g^(-1),均值为(34.72±8.22)mg·g^(-1)。建立了西洋参皂苷类成分的指纹图谱,相似度均达到了0.90以上,确定了10个共有成分峰构成西洋参的特征峰,聚类分析和主成分分析表明该地区西洋参皂苷类成分具有较好的稳定性。结论:建立的西洋参药材指纹图谱特征性强,方法简便,为山东产西洋参的鉴定和质量控制提供数据支持。

关键词：山东产西洋参人参皂苷超高效液相色谱指纹图谱质量评价聚类分析主成分分析

Gravitational wave echoes from strange quark stars in the equation of state with density-dependent quark masses

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Nuclear Science and Techniques 2023年第11期34卷 112-119页

作者： Jian‑Feng Xu Lei Cui Zhen‑Yan lu Cheng‑Jun Xia Guang‑Xiong peng School of arts and sciences Suqian UniversitySuqian 223800China Hunan Provincial Key Laboratory of Intelligent Sensors and Advanced Sensor Materials School of Physics and ElectronicsHunan University of Science and TechnologyXiangtan 411201China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

According to the recent studies,the gravitational wave(GW)echoes are expected to be generated by quark stars composed of ultrastiff quark *** ultrastiff equations of state(EOS)for quark matter were usually obtained either by a simple bag model with artificially assigned sound velocity or by employing interacting strange quark matter(SQM)depicted by simple reparameterization and *** this study,we investigate GW echoes with EOSs for SQM in the framework of the equivparticle model with density-dependent quark masses and pairing *** conclude that strange quark stars(SQSs)can be sufficiently compact to possess a photon sphere capable of generating GW echoes with frequencies in the range of approximately 20 ***,SQSs cannot account for the observed 72 Hz signal in GW170817 ***,we determined that quark-pairing effects play a crucial role in enabling SQSs to satisfy the necessary conditions for producing these types of echoes.

关键词： Strange quark star Gravitational wave echoes Color-flavour-locked phase Strange quark matter

Two-dimensional vanadium nanosheets as a remarkably effective catalyst for hydrogen storage in MgH_(2)

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Rare Metals 2021年第11期40卷 3195-3204页

作者： Zhi-Yu lu Hai-Jie Yu Xiong lu Meng-Chen Song Fu-Ying Wu Jia-Guang Zheng Zhi-fei Yuan Liu-Ting Zhang School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China Analysis and Testing Center Jiangsu University of Science and TechnologyZhenjiang 212003China

Magnesium hydride(MgH_(2)),which possesses high hydrogen density of 7.6 wt%,abundant resource and non-toxicity,has captured intense attention as one of the potential hydrogen storage ***,the practical application of Mg/MgH_(2) system is suffering from high thermal stability,sluggish absorption and desorption ***,two-dimensional(2D) vanadium nanosheets(V_(NS)) were successfully prepared via a facile wet chemical ball milling method and proved to be highly effective on improving the hydrogen storage performance of MgH_(2).For instance,the MgH_(2)+7 wt% V_(NS) composite began to release hydrogen at 187.2℃,152 ℃ lower than that of additive-free MgH_(2).At 300℃,6.3 wt% hydrogen was released from the MgH_(2)+7 wt% V_(NS) composite within 10 *** addition,the fully dehydrogenated sample could absorb hydrogen even at room temperature under hydrogen pressure of 3.2 MPa.X-ray diffractometer(XRD) and transmission electron microscopy(TEM)results confirmed metallic vanadium served as catalytic unit for facilitating the de/rehydrogenation reaction of MgH_(2).This finding presents an example of facile synthesis of two-dimensional(2D) vanadium with excellent catalysis,which may shed light on future design and preparation of highly effective layered catalysts for hydrogen storage and other energy-related areas.

关键词： Hydrogen storage Magnesium hydride Two-dimensional vanadium nanosheets Catalytic effect

麝香草酚破坏小肠结肠炎耶尔森氏菌细胞膜并抑制其生物被膜的形成研究

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陕西科技大学学报 2024年第1期42卷 51-58页

作者：高畅田露卢家兴龚国利陕西科技大学食品科学与工程学院陕西西安710021

小肠结肠炎耶尔森氏菌(Yersinia enterocolitica)是食品工业中常见的致病菌,其生物被膜是主要的污染源.为了阐明麝香草酚对***的抑制机制,本研究首先测定了最小抑制浓度(MIC)、最小抑制生物被膜浓度(MBIC)和最小清除生物被膜浓度(MBEC)... 详细信息

小肠结肠炎耶尔森氏菌(Yersinia enterocolitica)是食品工业中常见的致病菌,其生物被膜是主要的污染源.为了阐明麝香草酚对***的抑制机制,本研究首先测定了最小抑制浓度(MIC)、最小抑制生物被膜浓度(MBIC)和最小清除生物被膜浓度(MBEC),随后检测了细胞膜电位以及细胞内ATP和pH值的变化,最后在激光共聚焦显微镜(CLSM)、场发射扫描电子显微镜(FEGSEM)和光学显微镜下,直接观察了麝香草酚引起的细胞膜损伤及其对生物被膜的抑制作用.结果显示,麝香草酚对***的MIC为0.156 25 mg/mL,MBIC仅为1/16 MIC,改变了细胞形态并导致胞内ATP降低、膜去极化和pH下降.旨在探索麝香草酚抑制***及其生物被膜的机理,从而为麝香草酚能否作为植物源天然防腐剂提供更多参考.

关键词：麝香草酚小肠结肠炎耶尔森氏菌生物被膜细胞膜完整性

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语篇、语境、语义背景和关联理论

语言研究 2024年第1期44卷 1-7页

作者：陆俭明北京大学中国语言学研究中心/中文系北京100871

只有引进“语篇”这一概念,才能真正开展词语、语法、篇章的动态研究。而任何动态研究,都离不开语境。语境,就宏观谋篇而言,可细化为“情景语境”和“文化语境”;就微观用词选句而言,可细化为“语义背景”。语言的动态研究,不管涉及“... 详细信息

只有引进“语篇”这一概念,才能真正开展词语、语法、篇章的动态研究。而任何动态研究,都离不开语境。语境,就宏观谋篇而言,可细化为“情景语境”和“文化语境”;就微观用词选句而言,可细化为“语义背景”。语言的动态研究,不管涉及“情景语境”、“文化语境”还是“语义背景”,其重要理论支撑都是认知语言学的关联理论。

关键词：语篇语境情景语境文化语境语义背景关联理论