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A hydrogen-bonded organic framework containing fluorescent carbazole and responsive pyridyl units for sensing organic acids

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Chinese Chemical Letters 2024年第9期35卷 458-463页

作者： liangji chen Zhen Yuan Fudong Feng Xin Zhou Zhile Xiong Wuji Wei Hao Zhang Banglin chen Shengchang Xiang Zhangjing Zhang Fujian Key Laboratory of Polymer Materials College of Chemistry and Materials ScienceFujian Normal UniversityFuzhou 350007China

Hydrogen-bonded organic frameworks(HOFs)are a promising candidate for optical sensing,but the lack of effective design strategies poses significant challenges to the construction of HOFs for organic acid *** this work,the first HOF for organic acid sensing is reported by constructing a multiplepyridine carbazole-based dense HOF,namely HOF-FJU-206,from a tripyridine-carbazole molecular 3,6-bis(pyridin-4-yl)-9-(4-(pyridin-4-yl)phenyl)-9H-carbazole(CPPY)with carbazole center for luminescence,pyridyl sites for its responsive of hydrogen proton,and narrow channels in the dense framework for the diffusion of hydrogen ***-FJU-206 exhibits differential responsively fluorescence sensing and recovery properties to formic,acetic,and propionic acids with different molecular sizes and p Kavalue(acid dissociation constant).The dissociation degree of various acids can be determined by analyzing the slope of changes in both peak wavelength and intensity of in-situ fluorescence,which easily enables the dual-corrective recognition of different *** varying degree of protonation at pyridine sites is proved to be the reason for differential sensing of various acids,as demonstrated by1H NMR spectra,X-ray photoelectron spectroscopy(XPS)characterization,and modeling studies.

关键词： Hydrogen-bonded organic framework Organic acid sensing Acids recognition Carbazole luminescence Pyridine protonation

Microporous Nitrogen-Rich Polymers via Ullmann Coupling Reaction for Selective Adsorption of C_(2)H_(2) over CH_(4)

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Chinese Journal of Chemistry 2023年第5期41卷 514-520页

作者： Jitao Huang Qinfang Peng Chulong Liu Yingxiang Ye liangji chen Yuanchao Lv Yisi Yang Shimin chen Fahui Xiang Hao Zhang Zhangjing Zhang Shengchang Xiang Fujian Provincial Key Laboratory of Polymer Materials College of Chemistry and Materials ScienceFujian Normal University32 Shangsan RoadFuzhouFujian 350007China College of Chemistry and Materials Ningde Normal UniversityNingdeFujian 352100China

Acetylene purification from methane is challenging in the field of porous organic polymers(POPs).Herein,we have provided one-pot Ullmann coupling reaction to synthesize a series of POPs with rich N-sites,named FJU-POP-n,wherein the low-cost and non-toxic Cu(acac)2 and environmental-friendly glycerol are employed as catalyst and solvent,respectively.

关键词： Micro-porous materials Ullmann coupling reaction Copper-catalyzed Rich N-sites C_(2)H_(2)/CH_(4)separation C_(2)H_(2)/CO_(2)separation

Sticked-Layer Strategy to a Flexible-Robust Hydrogen-Bonded Organic Framework for Efficient C_(2)H_(2)/CO_(2)Separation

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CCS Chemistry 2024年第3期6卷 663-671页

作者： Zhen Yuan Xianghua Jiang liangji chen Junjie chen Lu Li Yisi Yang Yunbin Li Fahui Xiang Shengchang Xiang Banglin chen Zhangjing Zhang Fujian Key Laboratory of Polymer Materials College of Chemistry and Materials ScienceFujian Normal UniversityFuzhou 350007

Flexible-robust hydrogen-bonded organic frameworks(HOFs)are attracting increasing interest due to their excellent separation performance for important industrial gases,but the construction remains ***,a sticked-layer strategy is first proposed to construct a flexible-robust HOF,HOFFJU-8,from a donor(D)–π–acceptor(A)molecule 4,4′,4″,4‴-(pyrrolo[3,2-b]pyrrole-1,2,4,5-tetrayl)tetrabenzonitrile(DP-4CN).HOF-FJU-8 is amicroporous three-dimensional framework composed of two kinds of DP-4CN molecules,one acting as building units for the two-dimensional layer via C≡N···H–C hydrogen bond dimers and another as the sticks to link the layers along channels through D–Aπ···π*** activated framework HOF-FJU-8a possesses flexible-robust pore characteristics,as determined by the gas adsorption and in situ gas-loaded powder X-ray ***-FJU-8a exhibits adaptive adsorption and stronger binding affinity to C_(2)H_(2)rather than CO_(2)due to the flexible-robust nature,which can effectively separate acetylene and carbon dioxide mixtures.

关键词： hydrogen-bonded organic framework flexible-robust sticked-layer D-Aπ···πinteraction in situ powder X-ray diffraction C_(2)H_(2)/CO_(2)separation

Real-time 5-axis Spline Interpolation Method and Servo-controlling Structure of CNC System

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通讯和计算机（中英文版） 2010年第5期7卷 44-49页

作者： liangji chen Xianzhang Feng Huiying Li School of Mechatronics Engineering Zhengzhou Institute of Aeronautical Industry Management Zhengzhou 450001 China

Calculation of Space NURBS Curve Interpolation Error

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Journal of Computer and Communications 2020年第6期8卷 1-9页

作者： liangji chen Fei Gao Bo Zhao Longfei Ma School of Mechanical Engineering Tiangong University Tianjin China

Aiming at the problem of low accuracy of interpolation error calculation of existing NURBS curves, an approximate method for the distance between a point and a NURBS interpolation curve is proposed while satisfying the accuracy of the solution. Firstly, the minimum parameter interval of the node vector corresponding to the data point under test in the original data point sequence is determined, and the parameter interval is subdivided according to the corresponding step size, and the corresponding parameter value is obtained. Secondly, the distance from the measured point to the NURBS curve is calculated, and the nearest distance is found out. The node interval is subdivided again on one side of the nearest distance. Finally, the distance between the data point to be measured and each subdivision point is calculated again, and the minimum distance is taken as the interpolation error between the point and the NURBS curve. The simulation results of actual tool position data show that this method can more accurately obtain the error of spatial NURBS interpolation curve.

关键词： Computer-Aided Design NURBS Interpolation Curve Interpolation Error Approximation Solution

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滇池地区汉代觼饰研究

四川文物 2024年第3期 86-95页

作者：陈亮吉中山大学社会学与人类学学院

“策”作为汉代滇池地区所出车马器中常见的一类器物,以铜制为主,兼有少量玉制、铁制。因其名易与马鞭等它类器物相混淆,故为明确该类器物马饰带扣的功用,结合文献学分析将之重新定名为“觼”;同时对该地区所出考古学材料展开详细梳理,... 详细信息

“策”作为汉代滇池地区所出车马器中常见的一类器物,以铜制为主,兼有少量玉制、铁制。因其名易与马鞭等它类器物相混淆,故为明确该类器物马饰带扣的功用,结合文献学分析将之重新定名为“觼”;同时对该地区所出考古学材料展开详细梳理,以前后两期觼饰形制演变的类型学研究为基础,与其他地区同类器相较,探讨各型式觼传入的源流及在本土的改进。最终结合各期觼饰出土情境分析,以该类器物的兴替简要阐释两汉时期滇池地区汉文化“羁縻类型”的形成模式。

关键词：觼饰汉代汉文化“羁縻类型”

同方期刊数据库博看期刊评论

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加工路径段进给速度的转接及加减速处理方法

农业机械学报 2010年第1期41卷 200-204页

作者：陈良骥冯宪章郑州航空工业管理学院机电工程学院郑州450015

针对高速高精加工对数控系统在进给速度控制方面的要求,根据相邻路径段间的转接角大小建立了可直接进行段间转接的条件,并研究了该条件不成立时对转接速度的修正问题。提出了段内加减速的处理基本原则,并在保持路径段长度不变的基础上... 详细信息

针对高速高精加工对数控系统在进给速度控制方面的要求,根据相邻路径段间的转接角大小建立了可直接进行段间转接的条件,并研究了该条件不成立时对转接速度的修正问题。提出了段内加减速的处理基本原则,并在保持路径段长度不变的基础上对路径段内的进给速度重新进行规划,避免了以往插补前加减速方法中减速点和终点预测困难的问题。实际计算结果表明,相对零速度转接加减速处理方法,所提出的方法在同样保证加工精度等基础上提高了加工效率(每段约2%),在高速加工系统中可以得到较好应用。

关键词：高速加工进给速度加减速算法

曲率自适应条件下特征点选取的非均匀B样条曲线插值方法

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计算机辅助设计与图形学学报 2021年第9期33卷 1377-1387页

作者：陈良骥高飞赵波马龙飞桂林理工大学机械与控制工程学院桂林541004 天津空间电源科技有限公司天津300384 天津工业大学机械工程学院天津300387

针对计算机数控编程阶段生成的海量离散刀位数据,在满足预设插值精度的条件下,提出一种基于曲率自适应选取特征点的非均匀B样条曲线插值方法.首先,采用相邻3点形成近似圆弧的方法计算各个离散刀位数据点的曲率,将曲率分段点、曲率极大... 详细信息

针对计算机数控编程阶段生成的海量离散刀位数据,在满足预设插值精度的条件下,提出一种基于曲率自适应选取特征点的非均匀B样条曲线插值方法.首先,采用相邻3点形成近似圆弧的方法计算各个离散刀位数据点的曲率,将曲率分段点、曲率极大值点等特征数据点作为初始插值数据点,构造生成初始非均匀B样条插值曲线;其次,建立插值误差计算模型,并用于计算所有未参与插值的数据点与非均匀B样条插值曲线间的插值误差,在超出预设插值误差的曲率段内增加新的特征点,生成新的非均匀B样条插值曲线;重复上述过程,直至所有不在非均匀B样条插值曲线上的数据点都满足插值精度条件为止.对实际加工离散刀位数据的仿真计算结果表明,该方法即便去除了大量原始离散刀位数据,也能更好地保留原始刀位数据曲线在外形和精度方面的特征,且具有迭代计算次数少、数据点去除量大等特点,在海量离散刀位数据的样条化数控编程方面具有较高的应用价值.

关键词：数控编程非均匀B样条插值曲率自适应插值误差

三角网格曲面环形刀五轴加工宽行距刀具路径生成方法

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农业机械学报 2021年第5期52卷 392-403页

作者：陈良骥赵波马龙飞高飞天津工业大学机械工程学院天津300387

针对三角网格曲面五轴数控加工中普遍使用的截平面法加工行距较窄、加工效率较低的问题,提出一种可变行距的宽行加工刀具路径生成方法。首先,以三角网格数据重构为基础,提出一种基于KdTree网格区域划分的求交算法,实现了网格数据点的快... 详细信息

针对三角网格曲面五轴数控加工中普遍使用的截平面法加工行距较窄、加工效率较低的问题,提出一种可变行距的宽行加工刀具路径生成方法。首先,以三角网格数据重构为基础,提出一种基于KdTree网格区域划分的求交算法,实现了网格数据点的快速获取;然后,分析环形刀及三角网格曲面的几何特性,在无曲率干涉条件下提出通过改变侧倾角并优化前倾角使刀具有效切削半径最大化的方法,获得以加工行距最大化为优化目标的最佳刀具倾角组合;最后,结合三角网格曲面的特性建立一种环形刀刀具离散模型,并提出了相应的干涉检测与修正方法。仿真实验表明,在相同加工条件下,本文加工行距优化方法较现有方法明显增大了加工行距、提高了加工效率,而且所提出的刀具干涉与修正处理方法能有效避免局部刀底干涉及全局刀杆干涉现象的发生。

关键词：五轴数控加工三角网格曲面环形刀加工行距干涉处理