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智能混凝土与结构

工程力学 2007年第S2期24卷 45-61页

作者：李惠欧进萍哈尔滨工业大学土木工程学院大连116024 哈尔滨工业大学土木工程学院黑龙江哈尔滨150090大连理工大学辽宁哈尔滨150090

智能混凝土是通过将极少量具有某种特殊功能的材料复合于传统的混凝土材料中形成的具有多功能特性或某一种特殊功能特性的新型土木工程结构材料。与其他智能材料相比,智能混凝土是多功能本征性智能材料,可从本质上提高工程结构的性能。... 详细信息

智能混凝土是通过将极少量具有某种特殊功能的材料复合于传统的混凝土材料中形成的具有多功能特性或某一种特殊功能特性的新型土木工程结构材料。与其他智能材料相比,智能混凝土是多功能本征性智能材料,可从本质上提高工程结构的性能。自感知混凝土(纳米混凝土、碳纤维混凝土)、自阻尼混凝土和自愈合混凝土等是智能混凝土研究的热点。总结了近年来作者在智能混凝土的制备、性能、机理,以及智能混凝土结构等方面的研究成果,并指出需进一步研究的问题。

关键词：智能混凝土纳米材料碳纤维自感知自阻尼自愈合

Determination of the spatial and temporal variability of phytoplankton community structure in Daya Bay via HPLC-CHEMTAX pigment analysis

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Journal of Oceanology and Limnology 2018年第3期36卷 750-760页

作者： WANG Longhua ou Linjian HUANG Kaixuan CHAI Chao WANG zhaohui WANG Xiaomin JIANG Tao Key Laboratory of Sustainable Development of Marine Fisheries Ministry of AgricultureYellow Sea Fisheries Research InstituteChinese Academy of Fishery SeieneesQingdao 266071China Qingdao Engineering Research Center for Rural Environment Qingdao Agricultural UniversityQingdao 266109China College of Life Science and Technology Jinan UniversityGuangzhou 510632China

The spatial and temporal variability of the phytoplankton community structure in Daya Bay, South China Sea, were identified by using HPLC-CHEMTAX analytical techniques. The highest chlorophyll a(Chl a) concentrations were observed during summer(with an average value of 0.84 μg/L) and lowest ones during winter(with an average value of 0.33 μg/L). CHEMTAX processing revealed the seasonal succession of phytoplankton species in Daya Bay. During winter, diatoms were the dominant phytoplankton species and contributed 41.5% to total Chl a. Based on Chl a concentration, the average ratio of dinofl agellates to total phytoplankton biomass substantially increased with increasing temperature and nitrogen to phosphorus(N/P) ratio, reaching 52.2% in spring. Nutrient limitation shifted from phosphorus to nitrogen during summer. Moreover, this period was associated with the predominance of diatoms, which accounted for 71.1% of Chl a. Prasinophytes and cryptophytes were the other two dominant groups and particularly dominated during winter. Cyanobacteria became an important group during summer and autumn. Canonical correspondence analysis suggested that chrysophytes, dinofl agellates, and cryptophytes were strongly associated with high nitrate concentration, ammonium, dissolved inorganic nitrogen(DIN), and N/P ratio, and were negatively associated with temperature and phosphate. Diatoms and cyanobacteria were strongly associated with temperature, phosphate, and salinity, and are negatively influenced by nitrate, ammonium, DIN, and N/P ratio. Microscopic observations and pigment HPLC information were in good agreement for diatoms and dinofl agellates in the bay. This study demonstrated the usefulness of pigment analysis in investigating the distribution of phytoplankton groups in a complex physical environment, such as Daya Bay.

关键词： phytoplankton pigments environmental factor HPLC-CHEMTAX Daya Bay

THE PULP ELECTROCHEMISTRY OF FLOTATION SEPARATION FOR STIBNITE-ARSENOPYRITE BULK CONCENTRATE

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Journal of Central South University 1998年第1期10卷 5-7页

作者： ou Leming Feng Qiming Chen Jin(Department of Mineral Engineering, Central South University of Technology, Changsha 410083,China) 1. Department of Mineral Engineering Central South University of Technology 410083 Changsha China

In the thermodynamics, for flotation separation of the SbAs bulk concentrate system there is no potential extent using butyl xanthate as collector. However in the kinetics, there exists 150 mV in reducing potential of butyl dixanthogen on the surface of stibnite and arsenopyrite. In this paper, their reducing kinetic difference of electrochemistry was confirmed by pure mineral flotation under controlled potential, the artificial SbAs bulk concentrate flotation separation and UVspectrophotometic analysis. The electrochemical separation of SbAs bulk concentrate has been carried out. qualified concentrate has been obtained. Sbconcentrate contains Sb 4944 %, As 044 %, Sbrecovery is 8783 % and Asconcentrate contains As 1096 %, Asrecovery is 9466 %.

关键词： flotation stibnite arsenopyrite butyl xanthate pulp electrochemistry

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方柱非定常绕流与涡激振动的数值模拟

东南大学学报（自然科学版） 2005年第A01期35卷 35-39页

作者：徐枫欧进萍哈尔滨工业大学土木工程学院哈尔滨150090

为了研究二维刚体方柱的涡激振动和非定常绕流,利用计算流体力学软件Fluent6.0,引入雷诺应力模型求解不可压粘性流体Navier-Stokes方程,将Newmark-β方法的代码嵌入用户自定义函数(UDF)同软件连接来求解方柱的动力响应.用分块的方法建... 详细信息

为了研究二维刚体方柱的涡激振动和非定常绕流,利用计算流体力学软件Fluent6.0,引入雷诺应力模型求解不可压粘性流体Navier-Stokes方程,将Newmark-β方法的代码嵌入用户自定义函数(UDF)同软件连接来求解方柱的动力响应.用分块的方法建立初始网格,方柱和流场的耦合作用通过Fluent的动网格技术来实现,进行雷诺数从7000到42000范围内的模拟.得到静止方柱的升阻力系数和涡脱频率,其中雷诺数为22000结果与试验一致;同时得到方柱振动的位移和速度时程,以及“频率锁定”、“拍”和锁定段的位移“失谐”现象.

关键词：方柱涡激振动分块网格动网格频率锁定和失谐数值模拟

角度误差影响运动角锥棱镜反射特性的理论分析

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激光杂志 2001年第1期22卷 12-14页

作者：欧家鸣王瑞丽符德军李岩张书练云南师范大学物理系昆明650092 清华大学精密仪器系

角度误差对运动角锥棱镜反射特性有何影响 ,国内未见报导。本文根据矩阵光学理论证明了 ,角度制造误差将引起运动角锥棱镜反射光束空间方位的随机改变 ,但其改变属于高阶小量。这个结论对于将角锥棱镜作为He -Ne激光频率分裂位移传感器... 详细信息

角度误差对运动角锥棱镜反射特性有何影响 ,国内未见报导。本文根据矩阵光学理论证明了 ,角度制造误差将引起运动角锥棱镜反射光束空间方位的随机改变 ,但其改变属于高阶小量。这个结论对于将角锥棱镜作为He -Ne激光频率分裂位移传感器动镜使用。

关键词：角锥棱镜角度误差动态反射特性矩阵光学

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存在相关性风险的资产组合策略

系统工程理论与实践 2012年第3期32卷 630-639页

作者：冯玲欧华宇福州大学管理学院福州350002

经典金融理论的资产配置策略没有考虑相关性风险,而现实中,各种市场和各种资产之间的相关性是变化的,从而使投资组合风险上升.与传统金融理论基于完全市场条件下的组合选择不同,通过SJC-Copula刻画金融市场间不对称的尾部相关性,用CVaR... 详细信息

经典金融理论的资产配置策略没有考虑相关性风险,而现实中,各种市场和各种资产之间的相关性是变化的,从而使投资组合风险上升.与传统金融理论基于完全市场条件下的组合选择不同,通过SJC-Copula刻画金融市场间不对称的尾部相关性,用CVaR方法求出存在相关性风险的资产组合有效前沿及策略.通过沪港市场的实证研究,发现忽略上下尾相关性均会影响投资组合风险的估计,会使投资组合遭受极端的负收益;量化并有效地控制不对称的尾部相关性能够改善资产组合的表现.

关键词：相关性风险 Copula CVaR 有效前沿资产组合策略

Small incision lenticule extraction (SMILE) history, fundamentals of a new refractive surgery technique and clinical outcomes

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Eye and Vision 2014年第1期1卷 9-20页

作者： Dan z Reinstein Timothy J Archer Marine Gobbe London Vision Clinic 138 Harley StreetLondon W1G 7LAUK Department of Ophthalmology Columbia University Medical CenterNew YorkNYUSA Centre Hospitalier National d’Ophtalmologie ParisFrance

This review summarizes the current status of the small incision lenticule extraction(SMILE)*** the early work by Sekundo et *** Shah et al.,SMILE has become increasingly *** accuracy of the creation of the lenticule with the VisuMax femtosecond laser(Carl zeiss Meditec)has been verified using very high-frequency(VHF)digital ultrasound and optical coherence tomography(OCT).Visual and refractive outcomes have been shown to be similar to those achieved with laser in situ keratomileusis(LASIK),notably in a large population reported by Hjortdal,Vestergaard et *** in terms of the change in corrected distance visual acuity(CDVA)has also been shown to be similar to *** was expected that there would be less postoperative dry eye after SMILE compared to LASIK because the anterior stroma is disturbed only by the small incision,meaning that the anterior corneal nerves should be less affected.A number of studies have demonstrated a lower reduction and faster recovery of corneal sensation after SMILE than *** studies have also used confocal microscopy to demonstrate a lower decrease in subbasal nerve fiber density after SMILE than *** potential biomechanical advantages of SMILE have been modeled by Reinstein et *** on the non-linearity of tensile strength through the *** have reported a similar change in Ocular Response Analyzer(Reichert)parameters after SMILE and LASIK,however,these have previously been shown to be unreliable as a representation of corneal *** options after SMILE are *** addition applications of the SMILE procedure are also discussed including the potential for cryo-preservation of the lenticule for later reimplantation(Mohamed-Noriega,Angunawela,Lim et al.),and a new procedure referred to as endokeratophakia in which a myopic SMILE lenticule is implanted into a hyperopic patient(Pradhan et al.).Finally,studies reporting microdistortions in Bowman’s layer and cor

关键词： Small incision lenticule extraction(SMILE) Laser in situ keratomileusis(LASIK) Lenticule Cap Dry eye Corneal sensation Corneal innervation Corneal biomechanics Endokeratophakia

FBG智能传感器及其在土木工程中的应用研究

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功能材料 2004年第z1期35卷 152-156页

作者：周智欧进萍哈尔滨工业大学土木工程学院黑龙江哈尔滨150090 哈尔滨工业大学土木工程学院黑龙江哈尔滨150090

光纤光栅传感器已经越来越得到土木工程界的认可,并应用到了实际工程.针对大型土木工程结构长期健康监测的变形监测需要,在光纤光栅传输理论的基础上,分析了光纤光栅应变与温度传感特性以及光纤光栅应变传感的温度补偿原理和方法;研制... 详细信息

光纤光栅传感器已经越来越得到土木工程界的认可,并应用到了实际工程.针对大型土木工程结构长期健康监测的变形监测需要,在光纤光栅传输理论的基础上,分析了光纤光栅应变与温度传感特性以及光纤光栅应变传感的温度补偿原理和方法;研制开发出满足工程应用的光纤光栅封装传感器、FRP-OFBG复合智能筋、光纤光栅智能拉索;此外,考虑传感器开发和工程应用的需要,研究了光纤光栅应变传感的界面传递机理和误差修正.最后,建立了光纤光栅智能监测系统,并成功地将光纤光栅传感器应用到实际桥梁结构的施工与运营监测.

关键词：光纤光栅传感器封装传感器 FRP-OFBG复合智能筋智能拉索多层应变界面传递

Dawn of complex animal food webs:A new predatory anthozoan(Cnidaria)from Cambrian

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The Innovation 2022年第1期3卷 83-90页

作者： Qiang ou Degan Shu zhifei zhang Jian Han Heyo Van Iten Meirong Cheng Jie Sun Xiaoyong Yao Rong Wang Georg Mayer Early Life Evolution Laboratory State Key Laboratory of Biogeology and Environmental GeologyChina University of GeosciencesBeijing 100083China Department of zoology University of KasselKassel 34132Germany Shaanxi Key Laboratory of Early Life and Environment State Key Laboratory of Continental DynamicsDepartment of GeologyNorthwest UniversityXi’an 710069China Department of Geology Hanover CollegeHanoverIN 47243USA Cincinnati Museum Center Department of Invertebrate Paleontology1301 Western AvenueCincinnatiOH 45203USA School of Earth Science and Resources Chang’an UniversityXi’an 710054China

Cnidarians diverged very early in animal evolution;therefore,investigations of the morphology and trophic levels of early fossil cnidarians may provide critical insights into the evolution of metazoans and the origin of modern marine food ***,there has been a lack of unambiguous anthozoan cnidarians from Ediacaran assemblages,and undoubted anthozoans from the Cambrian radiation of metazoans are very rare and lacking in ecological ***,we report a new polypoid cnidarian,Nailiana elegans *** ***.,represented by multiple solitary specimens from the early Cambrian Chengjiang biota(-520 Ma)of South *** specimens show eight unbranched tentacles surrounding a single opening into the gastric cavity,which may have born multiple ***,*** displays a level of organization similar to that of extant *** analyses place *** in the stem lineage of Anthozoa and suggest that the ancestral anthozoan was a soft-bodied,solitary polyp showing octoradial ***,one specimen of the new polyp preserves evidence of predation on an epifaunal lingulid *** case provides the oldest direct evidence of macrophagous predation,the advent of which may have triggered the emergence of complex trophic/ecological relationships in Cambrian marine communities and spurred the explosive radiation of animal body plans.

关键词： China Cambrian solitary