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Discrimination of marine algal taxonomic groups based on fluorescence excitation emission matrix, parallel factor analysis and CHEMTAX

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Acta Oceanologica Sinica 2014年第12期33卷 192-205页

作者： CHEN Xiaona SU Rongguo BAI Ying SHI Xiaoyong yang rujun College of Chemistry and Chemical Engineering Ocean University of China

An in vivo three-dimensional fluorescence method for the determination of algae community structure was developed by parallel factor analysis （PARAFAC） and CHEMTAX. The PARAFAC model was applied to fluo-rescence excitation-emission matrix （EEM） of 60 algae species belonging to five divisions and 11 fluorescent components were identified according to the residual sum of squares and specificity of the composition profiles of fluorescent. By the 11 fluorescent components, the algae species at different growth stages were classified correctly at the division level using Bayesian discriminant analysis （BDA）. Then the reference fluo-rescent component ratio matrix was constructed for CHEMTAX, and the EEM-PARAFAC-CHEMTAX method was developed to differentiate algae taxonomic groups. The correct discrimination ratios （CDRs） when the fluorometric method was used for single-species samples were 100% at the division level, except for Bacil-lariophyta with a CDR of 95.6%. The CDRs for the mixtures were above 94.0% for the dominant algae species and above 87.0% for the subdominant algae species. However, the CDRs of the subdominant algae species were too low to be unreliable when the relative abundance estimated was less than 15.0%. The fluorometric method was tested using the samples from the Jiaozhou Bay and the mesocosm experiments in the Xiaomai Island Bay in August 2007. The discrimination results of the dominant algae groups agreed with microscopy cell counts, as well as the subdominant algae groups of which the estimated relative abundance was above 15.0%. This technique would be of great aid when low-cost and rapid analysis is needed for samples in a large batch. The fluorometric technique has the ability to correctly identify dominant species with proper abundance both in vivo and in situ.

关键词： CHEMTAX fluorescence excitatiqn-emission matrices in vivo fluorescent components,parallel factor analysis phytoplankton

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Characterization of iron diagenesis in marine sediments using refined iron speciation and quantized iron(Ⅲ)-oxide reactivity:a case study in the Jiaozhou Bay,China

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Acta Oceanologica Sinica 2017年第7期36卷 48-55页

作者： TAO Jing MA Weiwei ZHU Maoxu LI Tie yang rujun College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China

As a case study, refined iron（Fe） speciation and quantitative characterization of the reductive reactivity of Fe（Ⅲ）oxides are combined to investigate Fe diagenetic processes in a core sediment from the eutrophic Jiaozhou *** results show that a combination of the two methods can trace Fe transformation in more detail and offer nuanced information on Fe diagenesis from multiple perspectives. This methodology may be used to enhance our understanding of the complex biogeochemical cycling of Fe and sulfur in other studies. Microbial iron reduction（MIR） plays an important role in Fe（Ⅲ） reduction over the upper sediments, while a chemical reduction by reaction with dissolved sulfide is the main process at a deeper（〉 12 cm） layer. The most bioavailable amorphous Fe（Ⅲ） oxides [Fe（Ⅲ）am] are the main source of the MIR, followed by poorly crystalline Fe（Ⅲ） oxides [Fe（Ⅲ）pc）]and magnetite. Well crystalline Fe（Ⅲ） oxides [Fe（Ⅲ）wc] have barely participated in Fe diagenesis. The importance of the MIR over the upper layer may be a combined result of the high availability of highly reactive Fe oxides and low availability of labile organic matter, and the latter is also the ultimate factor limiting sulfate reduction and sulfide accumulation in the sediments. Microbially reducible Fe（Ⅲ） [MR-Fe（Ⅲ）], which is quantified by kinetics of Fe（II）-oxide reduction, mainly consists of the most reactive Fe（Ⅲ）am and less reactive Fe（Ⅲ）pc. The bulk reactivity of the MR-Fe（Ⅲ） pool is equivalent to aged ferrihydrite, and shows down-core decrease due to preferential reduction of highly reactive phases of Fe oxides.

关键词： iron oxides Jiaozhou Bay in China marine sediments microbial iron reduction reactivity speciation

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Analysis of Cu,Co,V and Zn in Coastal Waters of the East China Sea by Inductively Coupled Plasma Mass Spectrometry(ICP-MS)

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Journal of Ocean University of China 2016年第5期15卷 825-834页

作者： yang rujun NING Yutong ZHANG Aibin LI Yan SU Han College of Chemistry and Chemical Engineering Ocean University of China College of Marine Geoscience Ocean University of China

In this study, a simple method for the simultaneous determination of trace metals(Cu, V, Co, Zn) in coastal seawater using the Mg(OH)2 coprecipitation inductively coupled plasma mass spectrometry(ICP-MS) was developed. This multi-element method enables the simultaneous extraction of four metals, particularly Co and V. The recoveries of Cu, Co, V and Zn after Mg(OH)2 coprecipitation were 73%, 96%, 94% and 92%, which means that our procedure was well-suited to the determination of these four trace metals. The detection limits were 3.81, 0.18, 6.09 and 1.91 nmol L-1, respectively. Then, applying this method to the simultaneous determination of these four metals in coastal water samples from the East China Sea revealed that the concentrations of Cu, Zn, Co and V were higher in bottom waters compared to water at other depths, and higher concentrations were generally observed at the yangtze River estuary. Additionally, example vertical profiles of dissolved trace metal concentrations for the East China Sea in spring and autumn are compared. These findings indicate that Zn had the greatest seasonal variation followed by Cu, V and Co. For Zn and Co, the concentrations were higher during spring than during autumn. For Cu and V, the seasonal variation in the concentrations was opposite.

关键词： simultaneous dissolved inductively seasonal autumn seawater greatest ammonium waters hydroxide

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Evidence for coupled iron and nitrate reduction in the surface waters of Jiaozhou Bay

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Journal of Environmental Sciences 2021年第10期33卷 70-83页

作者： Kunyu Ma rujun yang Shenglu Qu Yingying Zhang Yuan Liu He Xie Minghan Zhu Mengqi Bi College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China School of Environmental Science and Engineering Yancheng Institute of TechnologyJiangsu 224051China Jiangsu Provincial Key Laboratory of Coastal Ecology and Pollution Control Yancheng 224051China

Iron and nitrate(NO_(3)^(-))are dominant physiologically required nutrients for phytoplankton growth,and iron may also play a key role in the marine nitrogen *** this study,we investigated the temporal and spatial distributions of dissolved iron(DFe)and Fe(Ⅱ)in the surface waters of Jiaozhou Bay(JZB)from April 2 to July 26,*** concentrations of DFe and Fe(Ⅱ)predominantly occurred in nearshore and estuarine stations and concentrations were generally higher in April and *** highest DFe concentration was observed along the coast of Hongdao(51.55 nmol/L)in May,while the lowest concentration was observed in the western coastal region(2.88 nmol/L)in *** highest and lowest Fe(Ⅱ)concentrations were observed in the Licun estuary(22.42 nmol/L)and outer bay(0.50 nmol/L)in May,*** calculated the proportions of nitrate,nitrite,and ammonium in dissolved inorganic nitrogen(DIN)as well as the ratio of Fe(Ⅱ)to DFe in all four *** mean Fe(Ⅱ)/DFe ratio was 0.48 in April,0.43 in May,0.69 in June,and 0.32 in *** mean ratio of NO_(3)^(-)to DIN was 0.78 in April,0.54 in May,0.20 in June,and 0.62 in ***_(3)^(-)/DIN continuously decreased in the first three months,while Fe(Ⅱ)/DFe remained high,which suggests that the reduction of iron and nitrate occurred simultaneously in the surface waters of JZB.

关键词： Iron Fe(Ⅱ) Jiaozhou Bay Flow injection chemiluminescence Redox Denitrification

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Size-Dependent Growth Rate of Nitzschia closterium at Different Concentrations of Petroleum Hydrocarbon

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Journal of Ocean University of China 2009年第1期8卷 45-50页

作者： yang rujun TANG Hongjie XIN Yu WANG Xiulin College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266003 P. R. China

The maximum growth rate ofNitzschia elosterium at various concentrations of petroleum hydrocarbon was studied. The influence of petroleum hydrocarbon on cell size as a function of concentration was discussed. The relationship between maximum growth rate of Nitzschia closterium and cell median equivalent spherical diameter （MESD） was also carefully studied. The experi- mental results showed that the growth rate of Nitzschia elosterium was generally suppressed by petroleum hydrocarbon, which had greater effects at both low and high concentrations than at intermediate concentrations. No significant changes in cell size distribu- tion were observed during the growth period ofNitzsehia closterium. The Gaussian function could give a clear description of the cell size distribution ofNitzsehia closterium, and the MESD value ranged from 2.71 to 6.82 μm. The MESD decreased when the cell was exposed to petroleum hydrocarbon, and the reduction of cell MESD was much more significant at both relatively high and low hydrocarbon concentrations. The presence of petroleum hydrocarbon changed the relationship between μmax, and MESD from an allometric function to a U-shaped curve. When the MESD was below 5.07 μm,μmax decreased along with increased MESD, whereas when MESD was above 5.07 μm, μmax increased along with MESD, which deviated from the allometric model.

关键词： Nitzschia closterium marine phytoplankton petroleum hydrocarbon cell size growth rate

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A novel long persistent luminescent material CaGeO_(3):Tb^(3+)with photo-stimulation properties

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Journal of Rare Earths 2024年第7期42卷 1233-1239,I0002页

作者： Wei Meng Xiaoyan Fu Tongyan Lin Zewen Liu Naihui Chen Jiaxu Zhang Runyao Liu rujun yang Long Chen Hongwu Zhang School of Chemistry and Material Sciences Ludong UniversityYantai264025China College of Materials Science and Engineering Xiamen University of TechnologyXiamen361024China College of Materials Xiamen UniversityXiamen361005China

A novel green long afterglow material CaGeO_(3):Tb^(3+)was synthesized by high temperature solid phase *** to the experimental results,CaGeO_(3):Tb^(3+)is a green long persistent luminescent(LPL)material with excellent ***_(3):Tb^(3+)shows LPL emission peak at 442,490.9,548.7,588.5 and 623.8 nm,corresponding to ^(5)D_(3) to^(7)F_(4)and^(5)D_(4)to^(7)F_(J)(J=6,5,4,3)transitions of Tb^(3+).Its CIE coordinates are(0.27,0.50),indicating that the afterglow emission is close to the light of green *** addition,after the excitation source is turned off,the afterglow time is longer than 90 *** an interval of 7 h,the photo-stimulation luminescence(PSL)can be observed by using 980 nm laser cyclic *** thermoluminescence(ThL)results show that there are three types of traps in the material and their depths are 0.666,0.774 and 0.892 eV respectively,which are caused by the doping of Tb^(3+).All the results show that CaGeO_(3):Tb^(3+)is an excellent long afterglow luminescent material.

关键词： Long persistent luminescence Photo-stimulation Trap CaGeO_(3):Tb^(3+) Rare earths

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关系数据库管理空间数据的方式下数据查询方法的研究

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武汉大学学报（信息科学版） 2005年第12期30卷 1104-1106,1119页

作者：黎展荣杨如军周新忠武汉大学遥感信息工程学院南宁市国土资源局南宁市东宝路3号530022

从逻辑上概括了基本的二维空间关系,描述新增的查询需求,阐述如何通过关系运算,推演出正确结果,在文章最后给出具体的例子,并对查询的问题作了些简单的总结。

关键词：空间数据关系数据库地理信息系统查询方法

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“互联网+”背景下饲料企业财务精细化管理优化路径探析

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中国饲料 2022年第10期 109-112页

作者：杨儒君马容重庆城市职业学院商学院重庆402160

在“互联网+”背景下,企业的经济业务活动呈现出多样化的发展趋势,传统财务管理模式难以满足企业投融资、资金运营和利润分配等内部管理需要,因此,财务精细化管理应运而生。为便于分析,从饲料企业的角度来对财务精细化管理做出论述,在... 详细信息

在“互联网+”背景下,企业的经济业务活动呈现出多样化的发展趋势,传统财务管理模式难以满足企业投融资、资金运营和利润分配等内部管理需要,因此,财务精细化管理应运而生。为便于分析,从饲料企业的角度来对财务精细化管理做出论述,在强调财务精细化管理重要性的基础上,探讨“互联网+”背景下饲料企业推行财务精细化管理的可行性和优化路径,以提高饲料企业的财务管理效率和核心竞争力。

关键词： “互联网+” 饲料企业精细化管理财务预算成本控制

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行星地球元素的演化与地球内部的相对运动:再论中国大地构造发展演化的新全球动力学理论

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地学前缘 2016年第4期23卷 166-182页

作者：杨志华晁会霞吴旭苏生瑞杨珺茹杨茹珺长安大学地球科学与资源学院陕西西安710054 国土资源部岩浆作用成矿与找矿重点实验室陕西西安710054

从相对论的质能互换、时空弯曲、相对速度(孪生子效应)、虫洞原理、奇点原理和量子力学的不确定性原理、多重历史思想出发,全面论述了秦岭和中国大地构造的基本特征与发展演化。从质能定律出发,提出地球的组成和地核、地幔、地壳3个圈... 详细信息

从相对论的质能互换、时空弯曲、相对速度(孪生子效应)、虫洞原理、奇点原理和量子力学的不确定性原理、多重历史思想出发,全面论述了秦岭和中国大地构造的基本特征与发展演化。从质能定律出发,提出地球的组成和地核、地幔、地壳3个圈层的形成是随核元素的燃烧阶段逐步实现的;按核燃烧的顺序,地球的组成是先形成原子序数小的长英质酸性核变岩,后形成原子序数大的铁镁质的超基性-基性核变岩。核元素转化过程中所产生的巨大能量是大地构造发展、演化唯一的动力来源。地球结构特征是物质组成在高能高速运动过程中时空弯曲的结果;DNA、RNA所决定的结构态的演变,在生物的俱生、俱灭中起决定性的作用;生物的进化是地球自身运用多维时空弯曲按质数律创生出来的。以多重历史思想和不确定性原理为基础,论述了中国大地构造的阶段发展、演化以及事件、组成、结构产生的随机性和概率性。从时空弯曲的普遍性出发,中国境内可建立青藏高原、西伯利亚和西南太平洋涡旋-甩出-热核反应3个一级构造单位。从相对速度的孪生子效应、虫洞原理出发,中国大陆造山带是高能高速的等离子-粒子流流体所形成的核变岩地质体,在短暂瞬间从地球深部抽拉-逆冲至地球的表层,与地表系统长期形成的地质体相互耦合、拼贴、混杂的产物,不存在任何形式的晋宁、加里东、华力西、印支、燕山和喜马拉雅等造山带拼贴增生的概念。抽拉-逆冲岩片构造或抽拉构造是造山带形成的主要形式,是岩石圈重要的运动方式。文中最后还对成矿作用、生物的俱生俱灭和地学中十多个地质难题进行了讨论,提出了地球质量极限值在地球演化和生物进化中的重要作用。在全面论述涡旋-热核反应动力体系在地球发展和中国大地构造演化中的作用后认为,新全球动力学理论是地球的无限空间之王。

关键词：相对论量子力学新全球动力学理论涡旋-热核反应动力体系抽拉构造大地构造

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自行走式地下掘进机器人姿态测量系统的设计

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传感技术学报 2013年第6期26卷 838-844页

作者：陈双叶牛经龙杨汝军北京工业大学电子信息与控制工程学院北京100124

针对当前自行走式地下掘进机器人姿态测量方法只能应用于静态测量的不足,提出一种可实时动态测量机器人行进过程中姿态的新方法。该系统的核心是两个激光发射器和多个激光接收器。发射器发射三束带有一定特征信息的激光,包括一束选通光... 详细信息

针对当前自行走式地下掘进机器人姿态测量方法只能应用于静态测量的不足,提出一种可实时动态测量机器人行进过程中姿态的新方法。该系统的核心是两个激光发射器和多个激光接收器。发射器发射三束带有一定特征信息的激光,包括一束选通光和两束扇形光。接收器接收到光束后,利用光束之间的几何关系、发射器的旋转速度和光束被接收的时间差来计算接收器相对于两发射器所在水平面的水平角和俯仰角,通过前方交会原理确定接收器即目标点的空间坐标。根据系统的测量原理建立测量模型,进行误差分析,建立误差模型,并对其进行仿真,与惯性导航测量误差进行比较。仿真结果表明该方法测量精度满足机器人位姿的测量要求。

关键词：自行走式掘进机器人姿态测量动态误差仿真

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