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Liquid crystal behavior of nanocrystalline cellulose induced by supercritical CO2

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Liquid crystal behavior of nanocrystalline cellulose induced...

Observation on Double Fertilization and Early Embryonic Development in Autotetraploid Polyembryonic Rice

河南省化学会2016年学术年会

作者： Yumei Ren Tao xu qun xu College of Materials Science and Engineering Zhengzhou University

In this work, nanocrystalline cellulose(NCC) with large-size oriented lamellar structure has been prepared by sulfuric acid hydrolysis of the commercial microcrystalline cellulose(MCC) and subsequently freeze-drying. Most notably, its rod-like morphology can self-assembly into chiral nematic phases where the NCC has the aligned orientation and can act as photonic structure. In addition,supercritical CO(SC CO) was used as green solvents to study the effect on self-assembly behavior of NCC. The self-assembling process of the NCC aqueous dispersions is exploited to prepare the flexible and transparent nanopaper via vacuum filtration. Both the NCC aqueous dispersions and NCC nanopaper show the liquid crystalline behavior observed by polarized optical microscopy(POM),creating a strongly birefringent phenomenon and brilliant iridescence. To the best of our knowledge so far no research is conducted on using SC CO to study the liquid crystal behavior of NCC. This general and straightforward approach to prepare chiral nematic materials may be potential in a variety of applications such as nonlinear optics, sensing, and catalysis, etc.

关键词： nanocrystalline cellulose self-assembly SC CO2 liquid crystal behavior nanopaper

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Rice science 2009年第2期16卷 124-130页

作者： DAI Xi-mei YANG xu HUANG qun-ce QIN Guang-yong Henan Provincial Key Laboratory of Ion Beam Bio-engineering Zhengzhou University Zhengzhou 450052 China

The process of double fertilization and the characters of embryo and endosperm development in an autotetraploid polyembryonic mutant rice IR36-Shuang were studied with a laser scanning confocal microscopy. Some abnormalities including degenerated ovary, abortive embryo sac, single fertilization, double-ovule and double-embryo and so on. were found dudng double fertilization and embryo development in IR36-Shuang. The rate of the abnormalities was 46.67% in IR36-Shuang, significantly higher than that in the control, an autotetraploid rice line IR36-4X （33.00%）. Cytological and embryonic evidences were provided for seed setting decline and the initiation of additional embryo in IR36-Shuang.

关键词： rice autotetraploid polyembryony double fertilization reproductive developmental character developmental biology embryonic development

CO_(2) coordination-driven top-down synthesis of a 2D non-layered metal-organic framework

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Fundamental Research 2022年第5期2卷 674-681页

作者： Yannan Zhou Pengfei Yan Suoying Zhang Yunxiao Zhang Hongwei Chang Xiaoli Zheng Jingyun Jiang qun xu College of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450052China Henan Institute of advanced technology Zhengzhou UniversityZhengzhou 450052China Key Laboratory of Flexible Electronics&Institute of Advanced Materials Nanjing Tech University30 South Puzhu RoadNanjing 211816China

Combining the physical advantages of two-dimensional(2D)inorganic nanosheets and the modular design and programmed structure of metal-organic frameworks(MOFs),2D MOFs remain at the forefront of functional material *** tremendous efforts,precise control in the synthesis of 2D nonlayered MOFs with predesigned topology for desired applications remains *** in the bottom-up synthesis of 2D nonlayered MOFs via ligand exchange motivated us to incorporate partial BTC(BTC=1,3,5-benzenetricarboxylate)ligand dissociation and CO_(2) capped coordination into the top-down treatment of bulk Cu-BTC MOF,leading to successful conversion of a 3D nonlayered network to a 2D Cu-based topological ***,a supercritical CO_(2)-containing solvent mixture is employed to provide the desired defect and coordination ***,our work introduces a new top-down concept based on modulated synthesis to fabricate high-quality 2D nonlayered MOFs for the first time.

关键词： Top-down Metal-organic frameworks 2D nonlayered Cu-BTC CO_(2)coordination Defect engineering

Wavelet chaotic neural networks and their application to continuous function optimization

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Natural Science 2009年第3期1卷 204-209页

作者： Jia-Hai Zhang Yao-qun xu 不详

Neural networks have been shown to be pow-erful tools for solving optimization problems. In this paper, we first retrospect Chen’s chaotic neural network and then propose several novel chaotic neural networks. Second, we plot the figures of the state bifurcation and the time evolution of most positive Lyapunov exponent. Third, we apply all of them to search global minima of continuous functions, and respec-tively plot their time evolution figures of most positive Lyapunov exponent and energy func-tion. At last, we make an analysis of the per-formance of these chaotic neural networks.

关键词： Wavelet Chaotic Neural Networks Wavelet Optimization

Genetic Diversity and Structure of New Inbred Rice Cultivars in China

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Journal of Integrative Agriculture 2012年第10期11卷 1567-1573页

作者： xu qun CHEN Hong WANG Cai-hong YU Han-yong YUAN Xiao-ping WANG Yi-ping FENG Yue TANG Sheng-xiang WEI Xing-hua State Key Laboratory of Rice Biology China National Rice Research Institute Development Center for Science and Technology Ministry of Agriculture

A total of 408 inbred rice cultivars bred in the last decade were analyzed for 24 SSR markers. The results showed the genetic diversity of indica cultivars was higher than that of japonica cultivars, and the genetic diversity of new cultivars raised in recent years was lower. Among the six rice cropping regions （RCRs） in China, genetic diversity was the highest in the central rice region （RCR-II） and the southwest rice region （RCR-III）. Genetic differences among subpopulations of japonica were more complex than those in indica. Differentiation among seasonal ecotypes and RCRs in indica populations was unclear, but differentiation between RCR-II and northeast rice region （RCR-V） was more distinct for japonica cultivars. Considering the North rice region （RCR-IV） has very low genetic diversity among the tested cultivars, it is important to broaden the genetic background for future cultivars in rice breeding programs.

关键词： rice Oryza sativa cultivars genetic diversity

Identification of the BTA8 gene reveals the contribution of natural variation to tiller angle in rice

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Journal of Integrative Agriculture 2024年第8期23卷 2868-2871页

作者： Junrong Liu Xingyu Wang Jing Wang Junhua Ye Mengchen Zhang qun xu Yaolong Yang Xinghua Wei Baoyan Jia Yue Feng State Key Laboratory of Rice Biology and Breeding China National Rice Research InstituteHangzhou 310006China College of Agronomy Shenyang Agricultural UniversityShenyang 110866China National Nanfan Research Institute(Sanya) Chinese Academy of Agricultural SciencesSanya 572024China

Plant architecture is a collection of major agronomic traits that determines rice grain production,and it is mainly influenced by tillering,tiller angle,plant height and panicle morphology(Wang and Li 2006).Tiller angle is one of the critical components that determines rice plant architecture,which in turn influences grain yield mainly due to its large impact on plant density(Wang et al.2022).

关键词： angle panicle agronomic

The Research of Power Supply Reliability in Urban Distribution Planning

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The Research of Power Supply Reliability in Urban Distributi...

构筑先进二维异质结构Ag/WO3-x用于提升光电转化效率（英文）

作者： LI QIN,He qun,xu Qingdao University Qingdao Power Supply Company

The power supply reliability of N-1 standard used in China and Engineering Recommendation P2/5 (ER P2/5) used in UK are introduced in this paper. The principle of relating the security to the size of the load block is described. Some internationally ‘recognized’ key performance indicators are compared and some important cautions of how to correctly use these indicators are emphasized. The relationship between reliability and pricing is also discussed.

关键词： Power Supply Reliability Urban Distribution Planning Standard

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物理化学学报 2019年第10期35卷 1157-1164页

作者：任玉美许群郑州大学材料科学与工程学院

等离子体激元诱导的光电化学反应被认为是太阳能转换的有效的替代方案。寻找具有增强的光吸收以及更长载流子寿命的高效光催化剂对于提高太阳能的转换效率至关重要,但其制备却具有挑战性。我们制备了Ag纳米颗粒均匀负载的二维(2D)无定... 详细信息

等离子体激元诱导的光电化学反应被认为是太阳能转换的有效的替代方案。寻找具有增强的光吸收以及更长载流子寿命的高效光催化剂对于提高太阳能的转换效率至关重要,但其制备却具有挑战性。我们制备了Ag纳米颗粒均匀负载的二维(2D)无定形三氧化钨(a-WO3-x),并对其进行退火处理,所获得的纳米异质结用作光电极材料具有高效的光电转化效率,并且其光氧化降解性能也显著提升。该光电阳极的高光电催化(PEC)性能归因于等离子体金属Ag纳米颗粒的局部表面等离子共振(LSPR)效应能够增强体系的光吸收和热电子转移。此外,局部结晶-非晶界面的构筑可以进一步提高光生电子-空穴对的分离效率并增加体系的导电性。

关键词：二维材料等离子体金属/半导体异质结构 PEC转换

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交通拥挤控制的实时决策支持模型

控制与决策 2005年第11期20卷 1221-1224页

作者：徐丽群上海交通大学管理学院上海200052

针对交通拥挤的快速检测和控制问题,设计了一种基于管理者知识和经验,能够实时反映交通拥挤状况的决策支持模型.设计的自动决策支持模型中包含了概念模型和推理模型,推理模型中集成了交通拥挤自动检测算法和拥挤交通量控制方案选择的模... 详细信息

针对交通拥挤的快速检测和控制问题,设计了一种基于管理者知识和经验,能够实时反映交通拥挤状况的决策支持模型.设计的自动决策支持模型中包含了概念模型和推理模型,推理模型中集成了交通拥挤自动检测算法和拥挤交通量控制方案选择的模糊推理算法.研究结果表明,采用自动决策支持模型能在一定程度上取代交通管理者对拥挤的管理,从而提高拥挤管理的效率和决策质量.

关键词：交通拥挤实时决策支持模型模糊控制