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B-N covalent bond-involved π-extension of multiple resonance emitters enables high-performance narrowband electroluminescence

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National Science Review 2024年第06期 243-253页

作者： Xingyu Huang Jiahui Liu Yulin Xu Guohao Chen Manli Huang Mingxin Yu Xialei Lv xiaojun yin Yang Zou Jingsheng Miao Xiaosong Cao Chuluo Yang Shenzhen Key Laboratory of New Information Display and Storage Materials College of Materials Science and EngineeringShenzhen University College of Physics and Optoelectronic Engineering Shenzhen University

Multi-boron-embedded multiple resonance thermally activated delayed fluorescence（MR-TADF） emitters show promise for achieving both high color-purity emission and high exciton utilization ***, their development is often impeded by a limited synthetic scope and excessive molecular weights,which challenge material acquisition and organic light-emitting diode（OLED） fabrication by vacuum deposition. Herein, we put forward a B–N covalent bond-involved π-extension strategy via post-functionalization of MR frameworks, leading to the generation of high-order B/N-based motifs. The structurally and electronically extended π-system not only enhances molecular rigidity to narrow emission linewidth but also promotes reverse intersystem crossing to mitigate efficiency roll-off. As illustrated examples, ultra-narrowband sky-blue emitters（full-width at half-maximum as small as 8 nm in n-hexane）have been developed with multi-dimensional improvement in photophysical properties compared to their precursor emitters, which enables narrowband OLEDs with external quantum efficiencies(EQEmax) of up to 42.6%, in company with alleviated efficiency decline at high brightness, representing the best efficiency reported for single-host OLEDs. The success of these emitters highlights the effectiveness of our molecular design strategy for advanced MR-TADF emitters and confirms their extensive potential in high-performance optoelectronic devices.

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瑞马唑仑联合纳布啡在无痛胃肠镜检查中的麻醉效果

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中国药物与临床 2024年第5期24卷 310-313页

作者：尹晓俊吕梁市兴县人民医院手术麻醉科山西吕梁033699

目的观察瑞马唑仑联合纳布啡在无痛胃肠镜检查中的麻醉效果。方法选取2022年1月至12月在吕梁市兴县人民医院进行无痛胃肠镜检查的患者95例,按照用药方法分为丙泊酚联合纳布啡组(PN组,47例)和瑞马唑仑联合纳布啡组(RN组,48例)。PN组采用... 详细信息

目的观察瑞马唑仑联合纳布啡在无痛胃肠镜检查中的麻醉效果。方法选取2022年1月至12月在吕梁市兴县人民医院进行无痛胃肠镜检查的患者95例,按照用药方法分为丙泊酚联合纳布啡组(PN组,47例)和瑞马唑仑联合纳布啡组(RN组,48例)。PN组采用丙泊酚联合纳布啡麻醉,RN组采用瑞马唑仑联合纳布啡麻醉。比较2组患者麻醉开始前、结束时和苏醒时的呼吸频率、心率、血氧饱和度(SpO_(2))及平均动脉压(MAP)水平,记录2组麻醉起效时间及苏醒时间,统计2组患者不良反应发生情况。结果PN组麻醉结束时和苏醒时RR、SpO_(2)、MAP水平低于麻醉开始前,心率水平高于麻醉开始前,差异有统计学意义(P0.05)。结论无痛胃肠镜检查中应用瑞马唑仑复合纳布啡麻醉的呼吸循环稳定效果优于丙泊酚联合纳布啡,不良反应更少,值得推广应用。

关键词：纳布啡无痛胃肠镜瑞马唑仑

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基于自信息熵的直觉模糊决策系统的属性约简

重庆邮电大学学报（自然科学版） 2024年第3期36卷 513-523页

作者：尹晓君冯涛张少谱石家庄铁道大学数理系石家庄050043 河北科技大学理学院石家庄050018

针对在直觉模糊集中,利用下近似构建的约简只考虑了下近似而忽略了上近似,从而导致一些信息丢失的问题,基于直觉模糊集的上、下近似提出了3种熵度量,并将其应用于直觉模糊决策信息系统的约简之中。在直觉模糊决策信息系统上定义用于描... 详细信息

针对在直觉模糊集中,利用下近似构建的约简只考虑了下近似而忽略了上近似,从而导致一些信息丢失的问题,基于直觉模糊集的上、下近似提出了3种熵度量,并将其应用于直觉模糊决策信息系统的约简之中。在直觉模糊决策信息系统上定义用于描述直觉模糊关系的3种不确定性度量,分别为平均决策指数、平均安全决策指数以及平均风险决策指数,并在此基础上依次提出了条件信息熵、条件粗糙熵和自信息熵,基于自信息熵给出了相应的约简定义以及属性约简算法。在多个数据集上的实验表明,所提出的属性约简算法与其他算法相比,约简结果更具有优越性以及鲁棒性。

关键词：属性约简直觉模糊决策信息系统条件信息熵条件粗糙熵自信息熵

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基于EMD分解和Levy-SSA-BP神经网络的齿轮故障诊断

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机械传动 2024年第5期48卷 152-157页

作者：徐婧雯杨平阴晓俊沈阳仪表科学研究院有限公司辽宁沈阳110043 沈阳工业大学信息科学与工程学院辽宁沈阳110870

为解决齿轮磨损早期故障诊断问题,提出了一种基于经验模态分解(Empirical Mode Decomposition,EMD)和算法优化反向传播(Back Propagation,BP)神经网络的故障诊断方法。首先,将声发射信号进行经验模态分解,得到本征模函数(Intrinsic Mode... 详细信息

为解决齿轮磨损早期故障诊断问题,提出了一种基于经验模态分解(Empirical Mode Decomposition,EMD)和算法优化反向传播(Back Propagation,BP)神经网络的故障诊断方法。首先,将声发射信号进行经验模态分解,得到本征模函数(Intrinsic Mode Function,IMF);其次,计算各IMF分量与原始信号的相关系数,并对各个分量进行特征提取,构成特征矩阵;最后,将特征矩阵放入经过Levy飞行和麻雀搜索算法优化后的BP神经网络中进行识别。对比BP神经网络和麻雀搜索算法优化后的神经网络,本文提出的算法准确率更高,且对轻微磨损故障的识别能力更好,可以用于早期齿轮故障诊断。

关键词：齿轮箱声发射故障诊断 BP神经网络麻雀搜索算法 Levy飞行经验模态分解

正压流体中具有beta效应的非线性Boussinesq方程及其多孤子解

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内蒙古大学学报（自然科学版） 2024年第2期55卷 132-137页

作者：贺艳飞尹晓军内蒙古农业大学理学院呼和浩特010018

本文主要考虑了具有beta效应的大尺度Rossby波控制方程的多孤子解。首先,从传统意义下的正压准地转位涡方程出发,利用多尺度分析法、坐标变换法、泰勒展开法以及分离变量法,推导出大尺度Rossby波的振幅满足带有beta效应的非线性Boussin... 详细信息

本文主要考虑了具有beta效应的大尺度Rossby波控制方程的多孤子解。首先,从传统意义下的正压准地转位涡方程出发,利用多尺度分析法、坐标变换法、泰勒展开法以及分离变量法,推导出大尺度Rossby波的振幅满足带有beta效应的非线性Boussinesq方程。然后,基于这个方程通过适当的变量代换给出了模型方程的Hirota双形式,并利用Hirota双线性方法获得了非线性Boussinesq方程的1-孤子解、2-孤子解、3-孤子解及N-孤子解。基于模型方程得到推广的beta效应能诱导生成Rossby波,并分析孤子解的结果表明,随着非线性系数的增大,孤子解的振幅在逐渐变小。

关键词： Boussinesq方程 Rossby波 Hirota方法多孤子解

Block Limit Analysis Method for Stability of Slopes During Earthquakes

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Journal of Shanghai Jiaotong university(Science) 2018年第6期23卷 764-769页

作者： yin xiaojun WANG Lanmin Institute of Engineering Mechanics China Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Engineering and Engineering Vibration of China Earthquake Administration Harbin 150080 College of Mining Engineering Heilongjiang University of Science and TechnologyHarbin 150022China Lanzhou Institute of Seismology China Earthquake AdministrationLanzhou 730000China

Based on the limit analysis upper bound method, a new mechanism of soil slope failure has been proposed which was consisted of plastic shear zone and rigid block zone. The different zones interface were regarded as discontinuity lines. Two sliding blocks of the slope were also incorporated horizontal seismic force and vertical gravity force. The velocities and forces were analyzed in two blocks, and the expression of velocity discontinuities was derived according to the principle of incompressibility. The external force done work for the blocks and the internal energy dissipated of the plastic shear zone and the velocity discontinuous were *** stability ratios were derived for the height of two-level slope with different rates to involve seismic and no seismic. The present stability ratios were compared to the previous study, which showed the superiority of the mechanism and the rationality of the analysis. The critical height of the slope can provide a theoretical basis for slope support and design.

关键词： soil slope stability ratio earthquake block limit analysis method

Undrained Stability Analysis of Three-Dimensional Rectangular Trapdoor in Clay

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Journal of Donghua University(English Edition) 2020年第4期37卷 334-339页

作者： yin xiaojun XIE Jun College of Mining Engineering Heilongjiang University of Science and TechnologyHarbin 150027China Independent Senior Geotechnical Engineering Consultant Toronto ON L4C 9G1Canada

A new collapse model of the trapdoors,three-dimensional rectangular trapdoor(3DRT),is presented for ground surface *** stability of 3DRT is examined with the upper bound method of plasticity limit analysis *** soil where the trapdoors are located is assumed to be a perfectly plastic model with a Tresca yield *** analysis technique is employed to investigate the collapse of *** model is divided into five different block types and added up to ten rigid *** to the law of conservation of energy,the critical stability ratios of 3DRT are obtained through a search *** results of upper bound solution for 3DRT are given,and three trapdoor models with depth various are discussed during the application in the stability analysis of square *** critical stability ratios can be used in the design of underground excavation and support force.

关键词： three-dimensional rectangular trapdoor upper bound solution stability ratio rigid block block analysis technique

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持有荷载法测试锚索锁定力试验研究

广东建材 2024年第5期40卷 91-96页

作者：邓署冬刘洪智尹小俊广州市建筑材料工业研究所有限公司广东聚科源建设工程质量检测有限公司

依托某深基坑支护工程,采用持有荷载法对基坑锚索展开锁定力测试,得到各实测锁定力,并对初始预应力损失原因进行分析,根据测试结果为优化锁定工艺提供了依据。同时分析各锚索的荷载-位移变化规律,通过对比发现荷载-位移增量曲线在分析... 详细信息

依托某深基坑支护工程,采用持有荷载法对基坑锚索展开锁定力测试,得到各实测锁定力,并对初始预应力损失原因进行分析,根据测试结果为优化锁定工艺提供了依据。同时分析各锚索的荷载-位移变化规律,通过对比发现荷载-位移增量曲线在分析判定锁定力值方面更加直观,具有重要参考作用。相关结论可为预应力锚索张拉锁定施工提供有益的参考。

关键词：预应力锚索持有荷载法锁定力预应力损失

Upper Bound Solution of Soil Slope Stability under Coupling Effect of Rainfall and Earthquake

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Journal of Donghua University(English Edition) 2019年第4期36卷 357-363页

作者： yin xiaojun WANG Lanmin Institute of Engineering Mechanics China Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Engineering and Engineering Vibration China Earthquake AdministrationHarbin 150080China College of Mining Engineering Heilongjiang University of Science and TechnologyHarbin 150022China Lanzhou Institute of Seismology China Earthquake AdministrationLanzhou 730000China

Based on the limit analysis upper bound method,a new model of soil slope collapse has been proposed which consists of two rigid block zones and a plastic shear *** slope was induced failure by coupling effect of rainfall and earthquake,and these blocks were also incorporated horizontal earthquake force and vertical *** velocities and forces were analyzed in three blocks,and the expression of velocity discontinuities was obtained by the principle of *** external force work for the blocks,the internal energy of the plastic shear zone and the velocity discontinuous were *** present stability ratios are compared to the prevenient research,which shows the superiority of the mechanism and rationality of the *** critical height of the soil slope can provide theoretical basis for slope support and design.

关键词： soil slope coupling effect upper bound solution stability ratio earthquake rainfall