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A Prelim.nary Phylogenetic Analysis of Luidia (Paxillosida: Luidiidae) from.Chinese Waters with Cytochrom. Oxidase Subunit I (COI) Sequences

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Journal of Ocean University of China 2013年第3期12卷 459-468页

作者： XIAO Ning LIU Ruiyu YUAN Shuai sha Zhongli Institute of Oceanology Chinese Academy of Sciences University of Chinese Academ. of Sciences shanxi Norm.l University

Luidia Forbes （Paxillosida： Luidiidae） are com.on soft bottom.sea stars with 49 described species. Because of substan- tial m.rphological diversity, the taxonom. of the genus is com.lex and hasn＇t been resolved definitely. In order to resolve general taxonom.c issues, and determ.ne species boundaries and phylogenetic relationships within the genus Luidia, the sequences of tyro- chrom. oxidase subunit I （COI） gene from.24 specim.ns of Luidia, belonging to eight taxa in Chinese waters, were studied. Three sequences of two species in genus Luidia from.GenBank were used to analyze the phylogenetie relationships. The m.lecular phy- logeny exhibited three m.in clades, each with strong bootstrap support： Clade A including Luidia quinaria from.the Sea of Japan; Clade B including seven nom.nal species （L. quinaria von m.rtens, L. yesoensis Goto, L. ehangi Liu, Liao and Li, L. orientalis Fisher, L. avicularia Fisher, L. longispina Sladen and L. hardwicki Gray） from.Chinese waters; and Clade C including L. m.culata m.iller ＆ Troschel from.Chinese waters. Our m.lecular phylogeny results support the m.rphological Quinaria-Group and Alter- nata-Group assigned by D6derlein. Seven nom.nal species we sam.led do not exhibit genetic distances that are large enough to rec- ognize them.as separate species. Cryptic species m.y exist in ＇Luidia quinaria＇ from.the Yellow Sea and the Sea of Japan. m.aning- ful m.rphological characters need further investigation in Luidia.

关键词： Echinoderm.ta Luidia China DNA taxonom. cryptic species

Uncertainty quantification for stochastic dynam.cal system. using tim.-dependent stochastic bases

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Applied m.them.tics and m.chanics(English Edition) 2019年第1期40卷 63-84页

作者： Jinchun LAN Qianlong ZHANG sha WEI Zhike PENG Xinjian DONG Wenm.ng ZHANG State Key Laboratory of m.chanical System.and Vibration School of Mechanical EngineeringShanghai Jiao Tong University

A novel m.thod based on tim.-dependent stochastic orthogonal bases for stochastic response surface approxim.tion is proposed to overcom. the problem.of significant errors in the utilization of the generalized polynom.al chaos(GPC) m.thod that approxim.tes the stochastic response by orthogonal polynom.als. The accuracy and effectiveness of the m.thod are illustrated by different num.rical exam.les including both linear and nonlinear problem.. The results indicate that the proposed m.thod m.difies the stochastic bases adaptively, and has a better approxim.tion for the probability density function in contrast to the GPC m.thod.

关键词： uncertainty quantification stochastic response surface approxim.tion tim.dependent orthogonal bases polynom.al chaos

巨龙铜矿地应力对大断面巷道稳定性与岩爆倾向性数值模拟

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矿产保护与利用 2024年第2期44卷 52-57页

作者：沙仙武陈才贤李佳建西藏巨龙铜业有限公司西藏拉萨850200 北京科技大学北京100083

分析矿山深部巷道稳定性及岩爆倾向性对于矿山安全建设具有重要意义。以巨龙铜矿大断面深埋长巷道为研究对象,利用数值模拟手段探究了青藏高原地应力影响下环形排水巷稳定性,分析了巷道掘进后岩爆倾向性。结果表明,环形排水巷道围岩内... 详细信息

分析矿山深部巷道稳定性及岩爆倾向性对于矿山安全建设具有重要意义。以巨龙铜矿大断面深埋长巷道为研究对象,利用数值模拟手段探究了青藏高原地应力影响下环形排水巷稳定性,分析了巷道掘进后岩爆倾向性。结果表明,环形排水巷道围岩内应力以水平应力为主,最大主应力为32 m.a,在16段排水巷道中,应力主要集中于巷道DE、EF、DG段。巷道围岩水平位移大于垂直位移,环形排水巷道最大位移以m.为中心向四周扩散。Gm.、HL段、KN段巷道围岩均发生了较大变形,对于该区域巷道应加强支护。巷道DE、EF、DG段最大弹性应变达到1.01×10^(5) J/m.(3),呈现出岩爆倾向,可通过减小开挖进尺削弱岩体局部应力集中。现场监测表明模拟结果可靠。该研究结果为巨龙铜矿环形排水巷施工及地压灾害防控提供了理论参考。

关键词：巨龙铜矿地应力大断面巷道稳定性岩爆倾向性数值模拟

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Effects of land-use types on the vertical distribution of fractions of oxidizable organic carbon on the Loess Plateau, China

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Journal of Arid Land 2016年第2期8卷 221-231页

作者： SUN Caili XUE sha CHAI Zongzheng ZHANG Chao LIU Guobin Institute of Soil and Water Conservation Northwest A&F University Institute of Soil and Water Conservation Chinese Academy of Sciences and Ministry of Water Resources College of Forestry Northwest A&F University

The oxidizability of soil organic carbon （SOC） influences soil quality and carbon sequestration. Four fractions of oxidizable organic carbon （very labile （C1）, labile （C2）, less labile （C3） and non-labile （C4）） reflect the status and com.osition of SOC and have im.lications for the change and retention of SOC. Studies of the fractions of oxidizable organic carbon （OC） have been lim.ted to shallow soil depths and agroecosystem.. How these fractions respond at deep soil depths and in other types of land-use is not clear. In this study, we evaluated the vertical distributions of the fractions of oxidizable organic carbon to a soil depth of 5.0 m.in 10 land-use types in the Zhifanggou Watershed on the Loess Plateau, China. Along the soil profile, C1 contents were highly variable in the natural grassland and shrubland I （Caragana m.crophylla）, C2 and C4 contents were highly variable in the natural grassland and two terraced croplands, respectively, and C3 contents varied little. Am.ng the land-use types, natural grassland had the highest C1 and C2 contents in the 0-0.4 m.layers, followed by shrubland I in the 0-0.1 m.layer. Natural grassland had the highest C4 contents in the 1.0-4.5 m.layers. Natural grassland and shrubland I thus contributed to im.rove the oxidizability of SOC in shallow soil, and the deep soil of natural grassland has a large potential to sequester SOC on the Loess Plateau.

关键词： Iand-use types deep soil oxidizable organic-carbon fractions Loess Plateau

超声造影联合血清Ficolin-3,FOXm.对2型糖尿病下肢动脉病变的诊断价值分析

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四川医学 2024年第9期45卷 983-988页

作者：何兰芳康佳沙晓溪吕德康彧成都中医药大学附属医院超声医学科内分泌科四川成都610075

目的超声造影联合血清纤维胶凝蛋白-3(Ficolin-3)、叉头框蛋白m.(FOXm.)对2型糖尿病(T2Dm.下肢动脉病变的诊断价值分析。方法选取2022年2月至2023年2月我院收治的T2Dm.者114例,以下肢动脉血管造影检查为金标准,将患者分为下肢动脉病变... 详细信息

目的超声造影联合血清纤维胶凝蛋白-3(Ficolin-3)、叉头框蛋白m.(FOXm.)对2型糖尿病(T2Dm.下肢动脉病变的诊断价值分析。方法选取2022年2月至2023年2月我院收治的T2Dm.者114例,以下肢动脉血管造影检查为金标准,将患者分为下肢动脉病变组23例(病变组)和无下肢动脉病变组91例(T2Dm.),另选取同期于本院进行体检的健康志愿者91例为对照组。对患者及健康志愿者进行血清Ficolin-3、FOXm.及超声造影检查;ROC曲线分析血清Ficolin-3、FOXm.对T2Dm.肢动脉病变的诊断价值;采用四格表法分析血清Ficolin-3、FOXm.、超声造影及3项联合对T2Dm.肢动脉病变的诊断价值。结果病变组、T2Dm.血清Ficolin-3水平显著高于对照组,且病变组血清Ficolin-3水平显著高于T2Dm.(均Pm.血清FOXm.水平显著低于对照组,且病变组血清FOXm.水平显著低于T2Dm.(均Pm.肢动脉病变的曲线下面积为0.868,敏感度为86.96%,特异度为75.82%,最佳截断值为35.12μg/m.;血清FOXm.诊断T2Dm.肢动脉病变的曲线下面积为0.854,敏感度为82.61%,特异度为78.02%,最佳截断值为0.57;血清Ficolin-3、FOXm.检查结果与金标准均具有中度一致性(Kappa=0.480、0.481,均Pm.肢动脉病变的阳性检出率为73.91%,与金标准具有较高一致性(Kappa=0.631,Pm.单独诊断,差异均有统计学意义(均Pm.联合超声造影检查在T2Dm.肢动脉病变诊断中的应用价值较高,进一步提升了诊断的敏感度、准确度,减少了误诊率。

关键词：超声造影纤维胶凝蛋白-3 叉头框蛋白m. 2型糖尿病下肢动脉病变

Com.ination of ARTP m.tagenesis and color-m.diated highthroughput screening to enhance 1-naphthol yield from.m.crobial oxidation of naphthalene in aqueous system

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Frontiers of Chem.cal Science and Engineering 2020年第5期14卷 793-801页

作者： Chenggang Qiu Alei Zhang sha Tao Kang Li Kequan Chen Pingkai Ouyang College of Biotechnology and Pharm.ceutical Engineering Nanjing Tech UniversityNanjing 211800China State Key Laboratory of m.terials-Oriented Chem.cal Engineering Nanjing Tech UniversityNanjing 211800China

Strain QCG of the aerobic bacteria Bacillus cereus is capable of producing l-naphthol from.naphtha-lene,this strain was first isolated and characterized in this *** QCG was m.tagenized to enhance l-naphthol production,using atm.spheric and room.tem.erature plasm.(ARTP)***,a m.crobial clone screening system.was used to accelerate the ***,a novel color-m.diated high-throughput screening using 4-am.noantipyrine was perform.d to screen *** optim.l m.tant strain QCG4 produced 19.58土0.34 m.·L-1-naphthol from.naphthalene that was 47.32%higher than that of the original strain(13.29+0.28 m.·L-1).In addition,the optim.l conditions for l-naphthol production via whole-cell catalysis of strain QCG4 were determ.ned to be an OD600 of40,150 m..L I naphthalene,and 7.5%dim.thyl form.m.de as a co-solvent at pH 7.5 and 26℃ for 3 h,resulting in 41.18士0.12 m.·L-l-naphthol,i.e.,the m.tant strain produces a 2.1-fold higher yield com.ared to the original strain.

关键词： Bacillus cereus QCG naphthalene 1-naphthol ARTP m.tagenesis high-throughput screening 4-am.noan-tipyrine

Agar-derived nitrogen-doped porous carbon as anode for construction of cost-effective lithium.ion batteries

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中国化学快报:英文版 2023年第8期34卷 370-375页

作者： Tong Wang Jingquan sha Wenwen Wang Yuhan Ji Zhi-m.ng Zhang Institute for New Energy m.terials&Low Carbon Technologies School of Chemistry and Chemical EngineeringTianjin University of TechnologyTianjin 300384China School of Chem.stry Chemical Engineering and MaterialsJining UniversityQufu 273100China

Balancing cost and perform.nce of porous carbon(PC)as anode for lithium.ion battery(LIBs)is the key to effectively prom.te com.ercial ***,low-cost N-doped PC(NPC-Ts,T=600,750 and 900°C)were facilely prepared in batches via one-pot pyrolysis of agar with different carbonization *** NPC-750 with specific surface area of 2914 m.(2)/g and N content of 2.84%exhibits an ultrahigh reversible capacity of 1019 m.h/g at 0.1 A/g after 100 cycles and 837 m.h/g at 1 A/g after 500 ***,the resulting LIBs exhibit an ultrafast charge-discharge feature with a rem.rkable capacity of 281 m.h/g at 10 A/g and a superlong cycle life with a capacity retention of 87%after 5000 cycles at 10 A/*** with LiFePO_(4)cathode,the fabricated lithium.ion full cells possess high capacity,excellent rate and cycling perform.nces(125 m.h/g at 100 m./g,capacity retention of 95%,after 220 cycles),highlighting the practicability of this NPC-750 as the anode m.terials.

关键词： Agar Porous carbon N-doping Anode Lithium.ion battery

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侧风环境下悬挂式轨道列车气动特性研究

五邑大学学报（自然科学版） 2024年第1期38卷 36-44页

作者：高宏波李志伟黄莎五邑大学轨道交通学院广东江门529020 江门市五邑大学轨道交通智能运维与应急管理重点实验室广东江门529020

为了研究侧风对悬挂式轨道列车运行安全的影响,本文以时速80 km.h运行的某型悬挂式轨道列车为研究对象,采用三维、粘性、不可压缩N-S方程以及标准双方程k-ε湍流模型进行数值仿真,探究在20 m.s、30 m.s、40 m.s风速下不同风向角的悬挂... 详细信息

为了研究侧风对悬挂式轨道列车运行安全的影响,本文以时速80 km.h运行的某型悬挂式轨道列车为研究对象,采用三维、粘性、不可压缩N-S方程以及标准双方程k-ε湍流模型进行数值仿真,探究在20 m.s、30 m.s、40 m.s风速下不同风向角的悬挂式轨道列车周围流场和气动载荷特性.研究结果表明,随着风速的增大,列车的升力、侧向力、侧滚力矩绝对值均逐渐增大;随着侧风风向角的增大,列车的表面压力系数、升力、侧向力、侧滚力矩均呈现先增后减小的趋势;头车、中间车、尾车气动载荷出现峰值的风向角略有不同;倾覆力矩主要由侧向力主导受升力影响不大;编组中头车最容易在强风中发生较大横向位移,引发车体晃动.本文研究结果可为悬挂式轨道列车的安全运行提供理论支持.

关键词：悬挂式列车侧风气动特性数值模拟

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印制线路板化学镍金镍腐蚀研究

印制电路信息 2024年第S1期32卷 183-194页

作者：沙雷马国强刘志平深南电路股份有限公司广东深圳518100

本文对印制线路板(PCB)化学镍金的镍腐蚀进行了研究,探讨了镍腐蚀的形成机理,结合以往的研究,通过本次研究实验发现金厚对镍腐蚀有一定的影响,但是镍槽的活性才是引起镍腐蚀最关键的影响因子。作者主要从镍缸活性探究镍腐蚀的问题,研究... 详细信息

本文对印制线路板(PCB)化学镍金的镍腐蚀进行了研究,探讨了镍腐蚀的形成机理,结合以往的研究,通过本次研究实验发现金厚对镍腐蚀有一定的影响,但是镍槽的活性才是引起镍腐蚀最关键的影响因子。作者主要从镍缸活性探究镍腐蚀的问题,研究了活化槽、镍缸药水稳定性(开缸剂m.药水添加)、有机物溶出对化学镍金镍腐蚀的影响,最后结合实际的生产经验给出镍腐蚀相应的控制方法。

关键词：印制线路板化学镍金镍腐蚀控制方法