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Embryology of Iris sanguinea Donn ex Horn. and its systematic relationship

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Journal of Forestry Research 2019年第6期30卷 2007-2020页

作者： lijuan fan Karl H.Hasenstein Ling Wang College of Landscape Architecture Northeast Forestry UniversityHarbin 150040People’s Republic of China Department of Biology University of Louisiana at LafayetteLafayetteLA 70504USA

Iris sangumea Dorm ex Horn. is a perennial cold-tolerant herbs of the Iris genus of Iridaceae, which has a well-formed, bright color and adaptability. Through understanding the fl ower bud differentiation, Sporogenesis, gametogenesis, fertilization and embryogenesis of I. sangumea, we developed fl owering regulation and control breeding. I. sangumea fl ower bud differentiation was observed in April for 21 days; in this stage, the early differentiation process was slow, temperature was more than 5 °C, if the temperature is shorter than this, most fl ower bud will have no differentiation, and turn to vegetative growth; later differentiation is faster and required temperature is from 5 to 8 °C and gradually rose to 10-12 °C. The temperature in April plays the defi nitely role in the number of bud differentiation. Three stamina contain tetrasporangiate anthers and a glandular tapetum. The anther wall is composed of four cell layers inclduding the epidermis, the endothecium, one middle layer and the secretory tapetum. The type of anther wall development the dicotyledonous type. After pollen maturation, the anther wall forms a double-layer containing only epidermis and endothecium. Simultaneous cytokinesis is of the continuous type during meiosis of microspore mother cell results in a zygomorphous or tetragonal tetrad. Mature pollen grains are two-celled. I. sangumea ’s stylar canal is hollow, open type style, and the gynoecium has three carpels. The ovaries have axial placentas. The ovule is anatropous, bitegmic and crassinucellate. The primary sporogenous cell differentiates directly as the megaspore. The megaspore tetrads are linear, T-shaped or juxtaposed. Generally, the fi rst of the tetrad megaspores at the chalaza becomes functional while the other three degenerate. A mature embryo sac with seven cells and eight nuclei embryo sac is of the polygonum type. For dichogamy, the male gametophyte matures about 2 days earlier than the female gametophyte. The pollen tube e

关键词： Iris sanguinea Donn ex Horn Flower bud diff erentiation Embryology

LiCoO2-catalyzed electrochemical oxidation of Li2CO3

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Nano Research 2016年第12期9卷 3903-3913页

作者： lijuan fan Daichun Tang Deyu Wang Zhaoxiang wang Liquan Chen Key Laboratory for Renewable Energy Chinese Academy of Sciences Beijing Key Laboratory for New Energy Materials and Devices Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences P. O. Box 603 Beijing 100190 China Division of Electric Vehicle Cells Ningde Contemporary Amperex Technology Co. Limited (CATL) Ningde 352100 China Ningbo Institute of Material Technology and Engineering Chinese Academy of Sciences Ningbo 315201 China

Lithium carbonate （Li2CO3） is very common in various types of lithium （Li） batteries. As an insulating by-product of the oxygen reduction reaction on the cathode of a Li-air battery, it cannot be decomposed below 4.75 V （vs. Li＋/Li） during recharge and leads to a large polarization, low coulombic efficiency, and low energy conversion efficiency of the battery. On the other hand, more than 10% of the Li ions from the cathode material are consumed during chemical formation of a Li-ion battery, resulting in low coulombic efficiency and/or energy density. Consequently, lithium compensation becomes essential to realize Li-ion batteries with a higher energy density and longer cycle life. Therefore, reducing the oxidation potential of Li2CO3 is significantly important. To address these issues, we show that the addition of nanoscaled LiCoO2 can effectively lower this potential to 4.25 V. On the basis of physical characterization and electrochemical evaluation, we propose the oxidization mechanism of Li2CO3. These findings will help to decrease the polarization of Li-air batteries and provide an effective strategy for efficient Li compensation for Li-ion batteries, which can significantly improve their energy density and increase their energy conversion efficiency and cycle life.

关键词： spinel LiCoO2 catalyst Li2CO3 electrochemical oxidation battery

Multi-port Network Modeling and Stability Analysis of VSC-MTDC Systems

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Journal of Modern Power Systems and Clean Energy 2024年第5期12卷 1666-1677页

作者： Shangning Tan Junliang Liu Xiong Du Jingyuan Su lijuan fan School of Electrical Engineering Chongqing UniversityChongqingChina the CSG Electric Power Research Institute China SouthernPower GridGuangzhouChina

The voltage source converter based multi-terminal high-voltage direct current(VSC-MTDC)system has attracted much attention because it can achieve the interconnection between AC ***,the initial phases and short-circuit ratios(SCRs)of the interconnected AC grids cause the steady-state phases(SSPs)of AC ports in the VSC-MTDC system to be *** can lead to the issues such as mismatches in multiple converter reference frame systems,potentially causing inaccuracies in stability analysis when this phenomenon is *** address the aforementioned issues,a multi-port network model of the VSC-MTDC system,which considers the SSPs of the AC grids and AC ports,is derived by multiplying the port models of different subsystems(SSs).The proposed multi-port network model can accurately describe the transmission characteristics between the input and output ports of the ***,this model facilitates accurate analysis of the system ***,it identifies the key factors affecting the system ***,the accuracy of the proposed multi-port network model and the analysis of key factors are verified by time-domain simulations.

关键词： Normalized sensitivity multi-port network model steady-state phase small-signal stability voltage source converter based multi-terminal high-voltage direct current(VSC-MTDC)

Characterizing the influence of gut microbiota on host tryptophan metabolism with germ-free pigs

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Animal Nutrition 2022年第4期11卷 190-200页

作者： Bingnan Liu Dongming Yu Jing Sun Xiaoyan Wu Zhongquan Xin Baichuan Deng lijuan fan Jian Fu Liangpeng Ge Wenkai Ren State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory of Lingnan Modern AgricultureNational Engineering Research Center for Breeding Swine IndustryGuangdong Provincial Key Laboratory of Animal Nutrition ControlCollege of Animal ScienceSouth China Agricultural UniversityGuangzhouChina Chongqing Academy of Animal Sciences ChongqingChina

Intestinal microbes are closely associated with host health,depending on metabolic crosstalk between the microbiota and *** metabolism is one of the best examples of metabolic crosstalk between intestinal microbiota and host;however,our understanding about the influence of intestinal microbiota on host tryptophan metabolism is ***,we established germ-free(GF)pig models to systemically explore the influence of intestinal microbiota on tryptophan *** GF pigs were kept in GF conditions throughout the experiment(GF group).Six GF pigs were transplanted with fecal microbiota from donor sows to act as control *** with control pigs,the GF pigs had remarkable alterations in tryptophan *** differential metabolites(P<0.05)were mainly found in the liver,circulation system and large ***,the alteration of metabolites in tryptophan metabolism varied among organs,especially for the serotonin *** GF pigs,tryptophan and kynurenine in the large intestine and 5-hydroxytryptophan in most organs were increased(P<0.05),while metabolites in the indole pathway in most organs were decreased(P<0.05).Collectively,our study reveals changes in tryptophan metabolism in GF pigs,highlighting the critical role of gut microbes in shaping host tryptophan metabolism.

关键词： Germ-free pig Gut microbiota Tryptophan Indole Kynurenine

Synthesis and study of λ-MnO_2 supported Pt nanocatalyst for methanol electro-oxidation

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Rare Metals 2010年第2期29卷 187-192页

作者： XIE Jia, LI Xiang, YU Zhihui, ZHANG lijuan, LI fan, and XIA Dingguo College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China College of Environmental and Energy Engineering Beijing University of Technology

A λ-MnO2 supported Pt nanocatalyst（5 wt.% Pt/λ-MnO2） was synthesized using a facile approach.X-ray diffraction（XRD）, X-ray photoelectron spectroscopy（XPS）, scanning electronic microscope（SEM）, transmission electron microscopy（TEM）, and energy disperse spectroscopy（EDS） were used for catalyst structure and morphology characterization, which showed that the metallic Pt particles were attached on a λ-MnO2 surface through the interaction between Pt and λ-*** voltammetry（CV） was used to test the catalytic activity of Pt/λ-MnO2 toward methanol oxidation, which showed that Pt/λ-MnO2 catalyst has much higher catalytic activity than baseline Pt/C catalyst.

关键词： electrochemistry composite catalyst MnO2 Pt methanol oxidation

盖斯凯尔夫人小说《露丝》疫病书写与社区共同体建构

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国外文学 2020年第4期 75-82,155页

作者：范丽娟苏州科技大学外国语学院

盖斯凯尔夫人的小说《露丝》以疫病流行为历史背景,通过对"堕落"女性露丝生存境遇的描写,展现社区共同体的人际关系、道德信念与人性道义等问题。其疫病书写与斑疹伤寒叙事成为传递道德判断的媒介与机制,在客观上推动了社会公共卫生向... 详细信息

盖斯凯尔夫人的小说《露丝》以疫病流行为历史背景,通过对"堕落"女性露丝生存境遇的描写,展现社区共同体的人际关系、道德信念与人性道义等问题。其疫病书写与斑疹伤寒叙事成为传递道德判断的媒介与机制,在客观上推动了社会公共卫生向前迈进。围绕疫病传播与消除过程,小说描绘了一个通过追溯斑疹伤寒疫病的传播而构成的看不见的社区网络,它超越了可见的地区甚至国家的界限,超越了亲属关系、社会关系甚至政治关系的范畴。在交通日渐便捷、信息不断流动的向工业化转型的时代,一个人与人紧密联系、共生共存的社区共同体显露出来,并促成人们的共同体意识从无知到认知和确立。

关键词：盖斯凯尔夫人《露丝》疫病书写共同体意识

习近平文化思想的形成逻辑、丰富内涵及原创性贡献

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江淮论坛 2023年第6期 15-20页

作者：范丽娟安徽省社会科学院社会学研究所合肥230051

全国宣传思想文化工作会议首次提出并系统阐释习近平文化思想。习近平文化思想深刻回答了“为什么要建设新时代中国特色社会主义文化、怎样建设新时代中国特色社会主义文化”等一系列重大问题,提出了新理念新思想新观点,构成了习近平新... 详细信息

全国宣传思想文化工作会议首次提出并系统阐释习近平文化思想。习近平文化思想深刻回答了“为什么要建设新时代中国特色社会主义文化、怎样建设新时代中国特色社会主义文化”等一系列重大问题,提出了新理念新思想新观点,构成了习近平新时代中国特色社会主义思想的文化篇。习近平文化思想的形成体现了历史逻辑、理论逻辑、实践逻辑的高度统一。习近平文化思想内涵丰富,涵盖了新时代文化发展的方向、原则、目标、任务、战略布局、方法路径等基本问题,并对思想理论、价值引领、新闻舆论、哲学社会科学、文艺创作、文明探源、遗产保护、网络治理、文明互鉴等方面作出全新的理论概括和战略指引。习近平文化思想的理念观点、核心要义、体系架构、思维方法、话语体系等具有独特的原创性贡献。

关键词：习近平文化思想形成逻辑丰富内涵原创性贡献

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共轭高分子材料荧光颜色的调节机理及方法

化学进展 2014年第11期26卷 1801-1810页

作者：陈云邵亚范丽娟苏州大学材料与化学化工学部高分子科学与工程系江苏省先进功能高分子材料设计及应用重点实验室苏州215123

近年来,共轭高分子作为荧光材料的研究受到越来越多的关注。共轭高分子相对于小分子发光材料在材料加工和发光性能上均具有极大的优势,从而在生物成像、传感、编码和光电材料等方面均有良好的应用前景,而其发光颜色的调节在某些应用中... 详细信息

近年来,共轭高分子作为荧光材料的研究受到越来越多的关注。共轭高分子相对于小分子发光材料在材料加工和发光性能上均具有极大的优势,从而在生物成像、传感、编码和光电材料等方面均有良好的应用前景,而其发光颜色的调节在某些应用中是极为重要的。本文首先对共轭高分子荧光颜色调节的两大类机理进行了阐述:直接调节共轭聚合物发光体系的能隙以改变发光颜色,或者将具有不同荧光颜色的材料发出的光叠加获得新的表观颜色。我们还对具体的调节手段进行了初步分类,包括物理共混法、共聚法、改变聚合物主链或侧基结构,以及改变共轭高分子聚集态等方法;在列举具体调节手段同时还引入了共轭高分子体系的实例说明,并对其中调节荧光颜色的可能机理进行了探讨。

关键词：共轭高分子荧光颜色调节机理

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众包对图书馆的影响及其运用

图书馆建设 2011年第1期 89-92页

作者：范丽娟南京理工大学图书馆江苏南京210094

众包理念和模式在图书馆领域的运用,将影响图书馆学理论架构,促进图书馆学理论创新;重新界定图书馆的组织边界,促进图书馆制度创新;打破图书馆专业化的门槛,促进图书馆技术和业务流程的创新。图书馆应充分借鉴众包的优势,鼓励大众进行... 详细信息

众包理念和模式在图书馆领域的运用,将影响图书馆学理论架构,促进图书馆学理论创新;重新界定图书馆的组织边界,促进图书馆制度创新;打破图书馆专业化的门槛,促进图书馆技术和业务流程的创新。图书馆应充分借鉴众包的优势,鼓励大众进行知识交流与创新,加强图书馆文献资源建设的针对性,提高图书馆文献揭示与读者检索的一致性,推动图书馆资源和网络信息的开发与利用,促进图书馆知识交流。

关键词：众包图书馆社会网络图书馆创新