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Synthesis of Optically Active trans-2-Aminocyclopropane-carboxylic Esters

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Chinese Chemical Letters 2006年第5期17卷 584-586页

作者： Jiang Chun ZHON Shang zhong liu qing Hua BIAN Ming Ming YIN Min WANG Department of Applied Chemistry China Agricultural University Beijing 100094

Two new optically active trans-2-atrfinocyclopropanecarboxylic esters （β-ACCs） of optical purity 91%-96% were concisely synthesized via ozonization, oxidation, Curtius rearrangement from commercial available optica... 详细信息

关键词： Cyclopropane chrysanthemate β-amino acid.

A FACILE SYNTHESIS OF 2-AND 2,4-UNSATURATED AMIDES

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Chinese Chemical Letters 1990年第3期1卷 211-212页

作者： Qi zhong Chang qing liu Chemistry Department,Yangzhou Teachers College,Yangzhou,225002

A convenient method for preparing unsaturated amides via telluro- nium salts employing solid potassium carbonate as a base with high stereo- selectivity in excellent yields has been developed.

关键词： A FACILE SYNTHESIS OF 2-AND 2,4-UNSATURATED AMIDES Za

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基于统计特征的时序数据符号化算法

计算机学报 2008年第10期31卷 1857-1864页

作者：钟清流蔡自兴中南大学信息科学与工程学院智能系统与智能软件研究所长沙410083

为克服SAX(符号聚合近似)算法对时序信息描述不完整的缺陷,提出基于统计特征的时序数据符号化算法,与SAX不同的是,该算法将时序符号看作矢量,而各时序子段的均值和方差则分别作为描述其平均值及发散程度的分量.由于该算法能够比SAX提供... 详细信息

为克服SAX(符号聚合近似)算法对时序信息描述不完整的缺陷,提出基于统计特征的时序数据符号化算法,与SAX不同的是,该算法将时序符号看作矢量,而各时序子段的均值和方差则分别作为描述其平均值及发散程度的分量.由于该算法能够比SAX提供更多的描述信息,因而在时序数据挖掘应用中能够获得比SAX更精确的结果.大量的实验也证实了它的出色表现.

关键词：时序数据挖掘符号化表示符号聚合近似

Preparation and Characterization of Azide-Functionalized Carbon Nanotubes

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含能材料 2013年第4期21卷 547-548页

作者： Jl Xiao-tang GE zhong-xue liu qing LI Tao-qi BU Jian-hua XU Ming BI Fu-qiang Xi'an Modern Chemistry Research Institute Xi' an 710065 China

Introducing the energetic groups to the surface of C_(60) and CNT, attracts special attentions because it because it might provide a new method for constructing enerfetic and stable high energy density materials(HEDMs).Peng R F prepared the nitro-modified C_(60) showing an insensitive action of ***,the research was rare, and many other energetic groups,such as azides were not used despite their extensive applications in energetic *** reported an one-step propartion of the azide-functionalized single-walled carbon nanotubes(SWNTs)(see in scheme 2) according to ***(SWNTs)(see in scheme) according to *** we characterized it with XPS and FTIR-ATR spectroscopy.

关键词：材料学 CNT 含能材料理论

Preparation of FeCoNi medium entropy alloy from Fe^(3+)-Co^(2+)-Ni^(2+)solution system

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 92-101页

作者： Zongyou Cheng qing Zhao Mengjie Tao Jijun Du Xingxi Huang Chengjun liu Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China Engineering Research Center of Frontier Technologies for Low-carbon Steelmaking(Ministry of Education) Shenyang 110819China

In recent years,medium entropy alloys have become a research hotspot due to their excellent physical and chemical *** controlling reasonable elemental composition and processing parameters,the medium entropy alloys can exhibit similar properties to high entropy alloys and have lower *** this paper,a FeCoNi medium entropy alloy precursor was prepared via sol-gel and coprecipitation methods,respectively,and FeCoNi medium entropy alloys were prepared by carbothermal and hydrogen *** phases and magnetic properties of FeCoNi medium entropy alloy were *** showed that FeCoNi medium entropy alloy was produced by carbothermal and hydrogen reduction at 1500℃.Some carbon was detected in the FeCoNi medium entropy alloy prepared by carbothermal *** alloy prepared by hydrogen reduction was uniform and showed a relatively high ***,the hydrogen reduction product exhibited better saturation magnetization and lower coercivity.

关键词： medium entropy alloy sol-gel co-precipitation carbothermal hydrogen reduction

Automatic Monitoring of Chilling Requirement for Sweet Cherry and Its Application in Protected Cultivation

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Agricultural Biotechnology 2016年第3期5卷 16-20,34页

作者： Daohui ZHANG Hongjun ZHAO Hechun GAO Yue TAN Jiawei WANG Xin CHEN Hairong WEI qing-zhong liu Shandong Institute of Pomology/Key Laboratory for Fruit Biotechnology Breeding of Shandong Province Taian 271000China Scientific Research Office Shandong Academy of Agricultural ScienceJinan 250100China Breeder Seed Farm of Ninghe County Ninghe 301500China

For sweet cherry, the economic benefit of protected cultivation is much higher than that of open field cultivation. However, problems such as nonuniform germination, aberrant flower, abortion, bad fruit setting and delayed maturation appear frequently due to the inaccurate regulation of chilling requirement. In order to solve the problems, an automatic system for monitoring, selecting and recording of chilling requirement in protected cultivation of sweet cherry was designed and developed. The system, which consisted of temperature detection, effective chilling temperature selection, signal conversion and output and chilling accumulation display, had been continuously used in protected cultivation of sweet cherry for 3 years and good effects had been achieved. The system monitored chilling accumu- lation accurately and made it more reasonable for the time selection of greenhouse covering, thus avoiding risks of nonuniform germination, bad fruit setting and de- layed maturation, etc. Under the coordinate application of this system with other modern measuring and controlling techniques such as automatic detection and alarming of temperature and humidity, the environment in greenhouses was regulated precisely that the uniform fruits were obtained and the expected yield, quality and harvest time were achieved.

关键词： Chilling requirement Sweet cherry Protected cultivation Automatic monitoring High quality and yield

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基于支持向量机的渐近式半监督式学习算法

计算机工程与应用 2006年第25期42卷 19-22页

作者：钟清流蔡自兴中南大学信息科学与工程学院智能系统与智能软件研究所

提出一种基于支持向量机的渐近式半监督式学习算法,它以少量的有标记数据来训练初始学习器,通过选择性取样规则和核参数来调节无标记样本的选择范围和控制学习器决策面的动态调节方向,并通过删除非支持向量来降低学习代价。仿真实验表明... 详细信息

提出一种基于支持向量机的渐近式半监督式学习算法,它以少量的有标记数据来训练初始学习器,通过选择性取样规则和核参数来调节无标记样本的选择范围和控制学习器决策面的动态调节方向,并通过删除非支持向量来降低学习代价。仿真实验表明,只要能够选择适当的选择性取样的阈值和核参数,这种学习算法就能够以较少的学习代价获得较好的学习效果。

关键词：支持向量机半监督式学习算法

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用于彩图分割的自适应谱聚类算法

计算机应用研究 2008年第12期25卷 3697-3699页

作者：钟清流蔡自兴中南大学信息科学与工程学院智能系统与智能软件研究所长沙410083 湖南省直机关行政学院长沙410001

针对自调节谱聚类算法的缺陷,提出一种新的自适应谱聚类算法。它用全局平均N近邻距离作为比例参数σ,利用本征矢差异来估计最佳聚类分组数k,达到了比前者更好的效果,且更容易实现。在彩色图像分割实际应用中的实验结果表明,该算法适应... 详细信息

针对自调节谱聚类算法的缺陷,提出一种新的自适应谱聚类算法。它用全局平均N近邻距离作为比例参数σ,利用本征矢差异来估计最佳聚类分组数k,达到了比前者更好的效果,且更容易实现。在彩色图像分割实际应用中的实验结果表明,该算法适应性强、计算代价小、精度较高,性能好于或至少不差于以往的类似算法。

关键词：谱分析谱聚类彩色图像分割

2D CaWO4 nanosheets derived from scheelite minerals for enhanced electrocatalysis in oxygen evolution reaction

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Science China Chemistry 2025年

作者： qing Sun Yongxiang Sun Yan Dong Hong zhong Hongbo Zeng National&Local United Engineering Laboratory for New Petrochemical Materials&Fine Utilization of Resources College of Chemistry and Chemical EngineeringHunan Normal University Department of Chemical and Materials Engineering University of Alberta College of Chemistry and Materials Engineering Hunan University of Arts and Science College of Chemistry and Chemical Engineering Central South University

Scheelite （CaWO4） mineral holds promise as a cost-effective and efficient catalyst for the oxygen evolution reaction （OER）crucial in renewable energy ***,challenges such as limited active site exposure and low electrocatalytic performance need *** this work,we have fabricated two-dimensional （2D） CaWO4nanosheets from scheelite minerals via a straightforward ultrasonic exfoliation method and evaluated their efficacy as OER *** to scheelite powders,these 2D nanosheets exhibited superior crystallinity and a 1.26-fold increase in electrochemical surface area,promoting active site *** 2D CaWO4nanosheet electrode demonstrated outstanding OER catalytic performance,achieving a current density of 20 mA/cm2at an overpotential of 290 m V in alkaline conditions,which was lower than that of bulk CaWO4electrodes （～340 mV）.Density functional theory calculations attributed this enhanced catalytic performance to moderate adsorption of oxygenated intermediates （*OH,*O,and*OOH） on the W sites of 2D *** situ electrochemical atomic force microscopy tests also confirmed the catalytic enhancement by 2D CaWO4nanosheets during *** findings demonstrate the potential of affordable and abundant mineral resources in advancing electrochemical catalysts for oxygen evolution,highlighting their broader application in sustainable energy technologies.

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