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Picoplankton and v.rioplankton abundance and community structure in Pearl Riv.r Estuary and Daya Bay, South China

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Journal of Env.ronmental Sciences 2015年第6期27卷 146-154页

作者： Zhixin ni Xiaoping Huang Xia Zhang Key Laboratory of Tropical Marine Bio-resources and Ecology South China Sea Institute of Oceanology Chinese Academy of Sciences South China Sea Env.ronmental Monitoring Center South China Sea Branch of the State Oceanic Administration Univ.rsity of Chinese Academy of Sciences

By using flow cytometry techniques, we inv.stigated the abundance and composition of the heterotrophic prokaryotes, v.rioplankton and picophytoplankton community in the Pearl Riv.r Estuary and Daya Bay in the summer of 2012. We identified two subgroups of prokaryotes, high nucleic acid（HNA） and low nucleic acid（LNA）, characterized by different nucleic acid contents. HNA abundance was significantly correlated with larger phytoplankton and Synechococcus（Syn） abundance, which suggested the important role of organic substrates released from primary producers on bacterial growth. Although LNA did not show any association with env.ronmental v.riables, it was a v.tal component of the microbial community. In contrast to prev.ous studies, the total v.rioplankton concentration had a poor relationship with nutrient av.ilability. The positiv. relationship between large-sized phytoplankton abundance and the v.I population confirmed that v.I was a phytoplankton-infecting v.ral subgroup. Although the v.II group（bacteriophages）was dominant in the v.rioplankton community, it was not related with prokaryotic abundance, which indicated factors other than hosts controlling v.II abundance or the uncertainty of v.rus-host coupling. With respect to the picophytoplankton community,our results implied that riv.r input exerted a strong limitation to Syn distribution in the estuary, while picoeukaryotes（Euk） were numerically less abundant and showed a quite different distribution pattern from that of Syn, and hence presented ecological properties distinct from Syn in our two studied areas.

关键词： Picoplankton v.rioplankton Community composition Flow cytometry

Modelling of finger-like channelled anode support for SOFCs application

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Science Bulletin 2016年第17期61卷 1324-1332页

作者： Bin Chen Haoran Xu Meng ni Building Energy Research Group Department of Building and Real EstateThe Hong Kong Polytechnic University

This paper established a numerical model for a solid oxide fuel cell （SOFC） button cell, focusing on the effects of finger-like channels on the gas transport process in the anode support. The current densities of channelled button cell and un-channelled button cell are compared at different operating temperature and v.ltage with H2 as the fuel. The H2 transport is discussed in detail, such as the mole fraction distribution of H2 in the porous layer, the diffusion flux and conv.ctiv. flux of Ha. It is found that the performance of SOFC can be improv.d by 2.60 % at 800 ~C, 0.5 v. com- pared with un-channelled SOFC due to the improv.d gas transport by the finger-like channels. Then, the model is further extended to study 2D-planar SOFC fuelled with syngas. The mole fraction gradients of H2, CO, CH4 and CO are all substantially reduced by the finger-like channels compared to un-channelled planar cell. It is found that the SOFC performance is improv.d by 5.93 % at 800℃, 0.5 v. when syngas fuel is used. The present study clearly demonstrated that the use of finger-like channels in the anode support is effectiv. in improv.ng the gas transport and the SOFC performance. The present model can be employed for subsequent optimization of the channel configuration for further performance improv.ment.

关键词： Phase inv.rsion CFD modelling Finger-like channels Concentration loss

Determination of Sulpiride by Linear Sweep Stripping v.ltammetry at a Mercury Electrode

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Chemical Research in Chinese Univ.rsities 2003年第1期19卷 24-27页

作者： ni Yong-nian Kokot Serge 等 DepartmentofChemistry NanchanguniversityNanchang330047P.R.China CenterforInstrumentalandDev.lopmentalChemistry SchoolofPhysicalandChemicalSciencesQueenslandUniversityofTechnology

This paper reports the electrochemical properties of sulpiride at a mercury electrode, especially its adsorptiv. characteristic. Sulpiride dissolv.d in a supporting electrolyte of a McIlv.ine buffer at pH 6 8 represents a sensitiv. and well defined reduction wav. by linear sweep stripping v.ltammetry. This method is based on the pre concentration and the reduction of sulpiride at a hung mercury drop electrode. The reduction peak potential is -1 72 v. v. . Ag AgCl) and the peak current is proportional to the concentration of sulpiride in the range of 0 1-0 6 μg/mL. The detection limit is 0 025 μg/mL obtained under the experimental conditions selected in this work. The electrochemical properties of this system were inv.stigated, and the proposed method was applied to the determination of sulpiride in pharmaceutical tablets with satisfactory results. It was compared well with the Uv.spectrophotometric method, showing a superior sensitiv.ty.

关键词： Sulpiride Linear sweep stripping v.ltammetry

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基于时差法的低功耗超声波三维海流测量系统

仪表技术与传感器 2024年第5期 91-97页

作者：谭旭李世阳倪晓波蔡兵兵上海交通大学电子信息与电气工程学院自然资源部第二海洋研究所

声学时差海流计具有高精度、高采样率、无盲区和不受海洋散射条件限制的优点,目前国内尚无时差海流计系统样机以及核心部件(四声道双晶换能器)的报道。为了实现对海洋矢量流速的长期精确测量,设计并研制了基于时差法的低功耗超声波三维... 详细信息

声学时差海流计具有高精度、高采样率、无盲区和不受海洋散射条件限制的优点,目前国内尚无时差海流计系统样机以及核心部件(四声道双晶换能器)的报道。为了实现对海洋矢量流速的长期精确测量,设计并研制了基于时差法的低功耗超声波三维海流测量系统,构建了四声轴三维矢量流速测量模型,通过有限元仿真设计并制备了小体积异形异构v.双晶换能器。系统采用低功耗STM32L431和MSP4306288为主控芯片,由TDC-GP22高精度时间测量模块、换能器驱动电路、低功耗放大滤波电路、SD卡存储模块等组成测量电路,通过测量换能器4个声轴上的超声波飞行时间差,得到海水的三维矢量流速。系统采用低功耗硬件系统设计,配合软件低功耗管理降低系统功耗。经实际测试,所研制的三维海流测量系统具有测量准确、低功耗、存储方便等优点。

关键词：海流计时差法低功耗三维流速超声换能器

中碳CrMo钢中Ti、Nb液析形貌及生成机理分析

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特殊钢 2024年第2期45卷 18-23页

作者：蒋乔张健倪燕红大冶特殊钢有限公司黄石435001

通过观察微合金Ti、Nb、v.42CrMo钢连铸坯中的液析形貌,以及液析经加热轧制后的变化,同时,采用热力学计算的方式推导液析生成机理。结果表明,在含w[Ti]0.012%、w[Nb]0.030%、w[v.0.030%、w[N]0.003 5%的42CrMo钢410 mm×530 mm连铸坯中... 详细信息

通过观察微合金Ti、Nb、v.42CrMo钢连铸坯中的液析形貌,以及液析经加热轧制后的变化,同时,采用热力学计算的方式推导液析生成机理。结果表明,在含w[Ti]0.012%、w[Nb]0.030%、w[v.0.030%、w[N]0.003 5%的42CrMo钢410 mm×530 mm连铸坯中,可观察到Ti、Nb以复合碳氮化物的形式析出,形成微米级液析,w[Ti]较高(70%~83%)的多呈多边形块状,w[Nb]较高(70%~85%)的多呈薄膜状或不规则块状,液析中基本不含v.素;Ti和Nb的碳氮化物液析可互溶并共同生长,Nb含量较高的液析以Ti含量较高的液析为核心长大为块状,部分液析以含硫夹杂物为核心形核并长大;连铸坯心部的碳氮化物液析较多,并且尺寸较大(最长达35μm),连铸坯表面的数量较少,尺寸较小(10μm以下);连铸坯经1 200℃加热并轧制后,液析可部分回溶,数量减少,尺寸减小,并且在轧制过程中破碎。

关键词： Ti Nb CrMo 微合金中碳钢液析

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高电压钴酸锂电池电解液研究进展

化工学报 2024年第9期75卷 3028-3040页

作者：彭丹卢俊杰倪文静杨媛汪靖伦湖南科技大学化学化工学院理论有机化学与功能分子教育部重点实验室湖南湘潭411201

钴酸锂(LiCoO_(2))具有高压实密度、高体积能量密度、优异的导电性能以及使用寿命长等优点,占据消费类电子产品的主要市场。LiCoO_(2)材料的理论比容量高达274 mAh/g,而其在4.2 v.电压下比容量仅为140 mAh/g。随着消费类电子产品对高... 详细信息

钴酸锂(LiCoO_(2))具有高压实密度、高体积能量密度、优异的导电性能以及使用寿命长等优点,占据消费类电子产品的主要市场。LiCoO_(2)材料的理论比容量高达274 mAh/g,而其在4.2 v.电压下比容量仅为140 mAh/g。随着消费类电子产品对高能量密度的迫切需求,提高LiCoO_(2)材料工作电压成为当前研究的热点。材料改性和功能电解液设计是实现高电压LiCoO_(2)电池的主要途径。相比较而言,功能电解液设计是一种高效且经济的途径,对高能量密度LiCoO_(2)电池的研发具有重要意义。从高压有机溶剂、高压添加剂以及局部高浓度电解液三个方面入手,综述了近年来国内外高电压LiCoO_(2)电池电解液的研究进展,重点阐述了电解液溶剂的氧化窗口、电极与电解液界面反应以及锂离子溶剂化结构对高电压LiCoO_(2)电池性能的影响。最后,对高电压LiCoO_(2)电池电解液的发展前景作出了总结和展望。

关键词：电化学锂离子电池界面电解液高电压钴酸锂

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离子络合物改性二维云母环氧树脂复合材料的制备及性能

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化工进展 2024年第9期43卷 5142-5156页

作者：楼高波姚潇翎倪静雯傅深渊刘丽娜浙江农林大学化学与材料工程学院浙江杭州311300 浙江农林大学国家木质资源综合利用工程技术研究中心浙江杭州311300 湖州万马高分子材料有限公司浙江湖州313100

为了实现环氧树脂(EP)的高性能化,将插层法得到的二维云母纳米片(MNs)与增韧型阻燃剂甲基膦酸-癸二胺离子络合物(MPA-DAD)复合,制备了一种环氧树脂多功能改性材料MNs@MPA-DAD。通过力学、UL-94、极限氧指数(LOI)、热重、锥形量热以及摩... 详细信息

为了实现环氧树脂(EP)的高性能化,将插层法得到的二维云母纳米片(MNs)与增韧型阻燃剂甲基膦酸-癸二胺离子络合物(MPA-DAD)复合,制备了一种环氧树脂多功能改性材料MNs@MPA-DAD。通过力学、UL-94、极限氧指数(LOI)、热重、锥形量热以及摩擦磨损等测试研究了MNs@MPA-DAD对环氧树脂复合材料的性能影响。结果表明:MPA-DAD中的离子键可充当牺牲键,耗散能量提升韧性。相较于纯EP,添加质量分数8%的MNs@MPA-DAD,环氧树脂复合材料的拉伸和弯曲韧性分别提高了302%和268%。二维的MNs可以作为物理屏障,抑制材料燃烧过程中热量和氧气的传递过程,与MPA-DAD协同发挥阻燃机制。EP/8%MNs@MPA-DAD的极限氧指数由纯EP的20.4%提高至28.9%,残炭率由8.9%提升至14.3%,UL-94测试通过了v.0级别,热释放速率峰值(PHRR)和总热释放(THR)分别降低了34.0%和19.7%。MNs@MPA-DAD能够产生均匀的润滑转移层,减少摩擦热的产生,避免熔化磨损,进而提高环氧树脂的耐磨性。EP/8%MNs@MPA-DAD的磨损面积较纯EP降低了76.6%。

关键词：纳米材料复合材料力学性能阻燃耐磨

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Collision-induced Rotational Energy Transfer in an Atom-Diatom System

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Chinese Journal of Chemical Physics 2008年第5期21卷 457-462页

作者： Yan-qing ni Jian Li Feng-cai Ma Department of Physics Liaoning University Shenyang 110036 China Department of Science Shenyang Institute of Aeronautical Engineering Shengyang 110036 China

As a further theoretical study of the collision-induced quantum interference on rotational energy transfer in an atom-diatom system, based on the first-Born approximation of time-dependent perturbation theory, taking into account the anisotropic Lennard-Jones interaction potential and the long-range interaction potential, the differential interference angles in singlet-triplet mixed states of CO A^1Π（v.9）-e3∑-（v.1） system in collision with He, Ne, Ar, and other partners were calculated theoretically. The relationships of differential interference angle v.rsus impact parameters, including collision parameter b and v.locity, are obtained.

关键词： Rotational energy transfer Collision-induced quantum interference Interference angle

钛合金超声滚压表面完整性分析及微动疲劳预测

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锻压技术 2024年第5期49卷 142-151页

作者：黄芳倪勇大金浙良张雪晖浙江工业职业技术学院机电工程学院浙江绍兴312000 天津工业大学数学科学学院天津300387 浙江工业职业技术学院继续教育学院浙江绍兴312000

为改善Ti6Al4v.合金加工表面形性和抗微动疲劳性能,采用超声滚压技术对其表面进行强化处理,并结合试验与数值分析研究了超声表面滚压强化后的表面完整性及其微动疲劳裂纹的萌生与扩展。试验研究表明:超声表面滚压处理使Ti6Al4v.合金... 详细信息

为改善Ti6Al4v.合金加工表面形性和抗微动疲劳性能,采用超声滚压技术对其表面进行强化处理,并结合试验与数值分析研究了超声表面滚压强化后的表面完整性及其微动疲劳裂纹的萌生与扩展。试验研究表明:超声表面滚压处理使Ti6Al4v.合金表面粗糙度明显降低、组织细化且沿深度方向呈梯度分布,并在钛合金表层引入了-573 MPa的残余压应力和表层硬度为447 HK、深度为120μm的加工硬化层。根据超声表面滚压的加工表面形性,建立了Ti6Al4v.合金微动疲劳有限元模型,结合最大相对滑动幅度、耗散能和等效损伤应力模型预测裂纹萌生位置,采用最大能量释放率准则预测裂纹萌生方向,最后基于ABAQUS和FRANC3D联合仿真实现了微动疲劳裂纹扩展预测。

关键词： Ti6Al4v.合金表面完整性微动疲劳超声滚压裂纹萌生裂纹扩展