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Chinese Chemical Letters 1990年第1期1卷 55-56页

作者： Ru Hong KANG Ji Sheng ZHU wen zi li Shu Rong liU Department of Chemistry,Hebei Normal University,Shijiazhuang

Seven diaryl ethers were synthesized with potassium fluoride coated alumina as a strong base and the addition of catalytic amount of PTC. The yield of diaryl ethers with addition of PTC was much higher than that witho... 详细信息

关键词： TEBA SYNTHESIS OF DIARYL ETHERS THROUGH PHASE TRANSFER CATALYSIS WITH POTASSIUN FLUORIDE COATED ALUMINA AS A STRONG BASE PTC AS

Frequent Introgressions from Diploid Species Contribute to the Adaptation of the Tetraploid Shepherd＇s Purse （Capsella bursa-pastoris）

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Molecular Plant 2015年第3期8卷 427-438页

作者： Ting-Shen Han Qiong Wu Xing-Hui Hou zi-wen li Yu-Pan Zou Song Ge Ya-Long Guo State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China University of Chinese Academy of Sciences Beijing 100049 China

is the most important ability for organisms to survive in diverse habitats. Animals have the option to escape from stressful environments, but plants do not. In plants, polyploids consist of about 30%-70% angiosperms and 95% ferns, of which some are important crops such as cotton and wheat. How polyploid plants adapt to various habitats has been a fundamental question remained largely unanswered. The tetra- ploid Shepherd＇s purse （Capsella bursa-pastoris） is one of the most successful plants on earth and has been distributed across the world, thus being an ideal model system for studying the adaptation of poly- ploids. We found that there are frequent introgressions from congeneric diploids to Shepherd＇s purse. Ecological niche modeling suggests that ecological differentiation is evident between the introgressed and non-introgressed C. bursa-pastoris, and the introgressions are a source of adaptation. This result links an evolutionary process to the adaptation of polyploids, and sheds light on the breeding strategy of poly- ploids as well. We conclude that frequent introgressions from congeneric diploids contributed to the acqui- sition of adequate genetic variations, thereby allowing C. bursa-pastoris to adapt to various habitats across the world. Our results highlight how a polypioid could have successfully established after it originated.

关键词： adaptation Capsella bursa-pastoris introgression polyploid

Stereoselective Excited-State Isomerization and Decay Paths in cis-Cyclobiazobenzene

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Stereoselective Excited-State Isomerization and Decay Paths ...

中国化学会第十六届全国光化学学术讨论会（2019）

作者： Teng-Shuo Zhang zi-wen li Qiu Fang Mario Barbatti Wei-Hai Fang Ganglong Cui Key Laboratory of Theoretical and Computational Photochemistry Ministry of EducationCollege of Chemistry Beijing Normal University Aix Marseille Univ CNRS ICR

Azobenzene（AB） is one of the most widely studied optical switching molecules. In recent years, photoswitchable macrocyclic systems with multiple ABs have been explored experimentally because of their potential applications in supramolecular chemistry, molecular machines, and light energy conversion. The photoisomerization and excited-state decay dynamics of these macrocyclic molecule is far from a complete understanding. Herein we have employed OM2/MRCI-based full-dimensional nonadiabatic dynamics simulations to explore the photoisomerization and subsequent excited-state decay of a macrocyclic cyclobiazobenzene（CBA） molecule. We found two stereoselective photoisomerization and excited-state decay pathways, which correspond to the clockwise and counterclockwise rotation motions with respect to the N=N bond of the azo group. The clockwise isomerization channel is much more favorable than the counterclockwise one with a ratio of 74% vs. 26%. The present work demonstrates that stereoselective pathways exist not only in the photoisomerization of isolated azobenzene-like systems but also in macrocyclic systems with multiple azobenzenes.

关键词： Cyclobiazobenzene Stereoselectivity Excited-State Isomerization

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IGBT逆变焊机数字温度监控系统设计

电焊机 2010年第9期40卷 29-33页

作者：余棉水谢宇温自力广东工贸职业技术学院广东广州510510 广州长胜焊接设备有限公司广东广州510630

设计了一种采用数字温度传感器DS18B20和AT89C2051单片机组成的焊机温度智能监控系统。系统首先通过软件对各监测点设置不同的报警温度,然后循环监测各点的温度,一旦出现超温则及时关闭焊机输出并报警,从而有效地保护了焊机中的重要元器... 详细信息

设计了一种采用数字温度传感器DS18B20和AT89C2051单片机组成的焊机温度智能监控系统。系统首先通过软件对各监测点设置不同的报警温度,然后循环监测各点的温度,一旦出现超温则及时关闭焊机输出并报警,从而有效地保护了焊机中的重要元器件,大大提高了焊机的可靠性。实际应用表明,该系统结构简单,抗干扰能力强,测温快速且精度高,具有广泛的应用前景。

关键词： DS18B20 数字温度传感器单总线 IGBT逆变焊机

基于CAN总线的数字化CO_2焊接电源设计

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制造业自动化 2010年第7期32卷 155-159页

作者：余棉水谢宇温自力广东工贸职业技术学院广州510510 广州长胜焊接设备有限公司广州510630

设计了以CAN总线为基础,以TMS320LF2407A为控制核心的数字化CO2焊接电源。根据CO2焊接工艺的特点,编程实现了整个焊接系统的数字化控制。文中对系统的硬件电路设计、CAN总线的通信协议设计以及软件设计进行了较详细的说明。试验结果表明... 详细信息

设计了以CAN总线为基础,以TMS320LF2407A为控制核心的数字化CO2焊接电源。根据CO2焊接工艺的特点,编程实现了整个焊接系统的数字化控制。文中对系统的硬件电路设计、CAN总线的通信协议设计以及软件设计进行了较详细的说明。试验结果表明,系统获得了良好的控制效果,为网络化及智能化控制提供了良好的平台。

关键词： DSP CAN总线 CO2焊数字化控制

三配位Au(I)配合物热激活延迟荧光机理的量子力学/分子力学研究:晶体环境的关键作用

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Chinese Journal of Chemical Physics 2023年第2期36卷 175-185,I0007-I0025,I0054,I0055页

作者：李子问彭灵雅宋秀芳高远君崔刚龙北京师范大学化学学院光化学理论与计算重点实验室北京100875

近年来,三配位Au(I)配合物的热激活延迟荧光现象引起了人们的关注.然而,其发光机理尚不清楚.本文采用密度泛函理论、含时密度泛函理论以及量子力学/分子力学方法研究了Au(I)配合物在气相和晶体中的激发态性质.在这两种环境下,S_(1)和T_... 详细信息

近年来,三配位Au(I)配合物的热激活延迟荧光现象引起了人们的关注.然而,其发光机理尚不清楚.本文采用密度泛函理论、含时密度泛函理论以及量子力学/分子力学方法研究了Au(I)配合物在气相和晶体中的激发态性质.在这两种环境下,S_(1)和T_(1)激发态主要涉及HOMO和LUMO,表现出明显的金属-配体电荷转移和配体内电荷转移特征.HOMO和LUMO的空间分离有助于缩小S_(1)和T_(1)之间的能隙,加速T_(1)到S_(1)的反向系间窜跃.在300K时,反向系间窜跃速率比磷光发射速率快,实现了热激活延迟荧光.但在77 K时,反向系间窜跃通道阻塞,热激活延迟荧光消失,因此低温时实验上只观测到磷光现象.这项工作有助于进一步了解有机金属配合物的热激活延迟荧光发光机理.

关键词：热激活延迟荧光 Au(I)配合物密度泛函理论激发态环境效应

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高精度大范围的光学晶体温度控制系统

光学精密工程 2018年第7期26卷 1604-1611页

作者：朱均超豆梓文李嘉强徐晓明天津理工大学电气电子工程学院天津市复杂系统控制理论及应用重点实验室天津300384 核工业理化工程研究院天津300180

为解决固体激光器工作时光学晶体产生的热沉积问题,保证其工作性能稳定,提出了一种基于半导体制冷器(TEC)的高控温精度、大控温范围光学晶体温度控制方案。分析了TEC的工作特性和光学晶体的热效应与传热机理,将TEC工作过程中自身温度变... 详细信息

为解决固体激光器工作时光学晶体产生的热沉积问题,保证其工作性能稳定,提出了一种基于半导体制冷器(TEC)的高控温精度、大控温范围光学晶体温度控制方案。分析了TEC的工作特性和光学晶体的热效应与传热机理,将TEC工作过程中自身温度变化引起的电气特性改变与光学晶体温度的变化同时纳入控制环节,建立了温度-电流双闭环温度控制模型,设计并完成了一套高控温精度、大控温范围的光学晶体温度控制系统。实验结果表明:本系统在-15~120℃的温度控制范围内,可以迅速稳定在任一设定的温度点,其控温精度优于±0.002℃;当设定温度和实际温度之间的偏差在20℃以内时,其收敛稳定时间小于60s,可以满足固体激光器中光学晶体对控温范围与精度的要求。

关键词：光学晶体温度控制双闭环高精度大范围

An efficient quantum proactive incremental learning algorithm

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 49-57页

作者： lingxiao li Jing li Yanqi Song Sujuan Qin Qiaoyan wen Fei Gao State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications School of Cyberspace Security Beijing University of Posts and Telecommunications

In scenarios where a large amount of data needs to be learned, incremental learning can make full use of old knowledge, significantly reduce the computational cost of the overall learning process, and maintain high performance. In this paper, taking the MaxCut problem as our example, we introduce the idea of incremental learning into quantum computing, and propose a Quantum Proactive Incremental Learning algorithm(QPIL). Instead of a one-off training of quantum circuit, QPIL contains a multi-phase training on gradually-increased subgraphs of all vertices, proactively reducing large-scale problems to smaller ones to solve in steps, providing an efficient solution for MaxCut. Specifically, some vertices and corresponding edges are randomly selected for training to obtain optimized parameters of the quantum circuit at first. Then, in each incremental phase, the remaining vertices and corresponding edges are gradually added and the parameters obtained from the previous phase are reused in the parameter initialization of the current phase. We perform experiments on 120 different small-scale graphs, and it shows that QPIL performs superior to prevalent quantum and classical baselines in terms of approximation ratio(AR), time cost, anti-forgetting, and solving stability. In particular, QPIL's AR surpasses 20% of mainstream quantum baselines, and the time cost is less than 1/5 of them. The idea of QPIL is expected to inspire efficient and high-quality solutions in large-scale Max Cut and other combinatorial optimization problems.

关键词： variational quantum algorithm incremental learning multi-phase training MaxCut quantum computing

腹腔镜阑尾切除术治疗急性阑尾炎的临床疗效及其安全性评价

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昆明医科大学学报 2016年第8期37卷 119-122页

作者：潘子鹏李闻保亭县人民医院外一科海南保亭572300 解放军总医院海南医院海南三亚572013

目的探讨腹腔镜阑尾切除术手术治疗急性阑尾炎患者临床疗效分析及其安全性.方法纳入的92例急性阑尾炎患者,随机数字表法随机分为观察组(n=46)与对照组(n=46).观察组给以腹腔镜阑尾切除术治疗,对照组以传统开腹阑尾切除术治疗.比较2组术... 详细信息

目的探讨腹腔镜阑尾切除术手术治疗急性阑尾炎患者临床疗效分析及其安全性.方法纳入的92例急性阑尾炎患者,随机数字表法随机分为观察组(n=46)与对照组(n=46).观察组给以腹腔镜阑尾切除术治疗,对照组以传统开腹阑尾切除术治疗.比较2组术中情况、术后情况及术前、术后1 d和3 d WBC水平变化.结果观察组手术时间短于对照组(t=4.049,P0.05),出血量少于对照组(t=20.748,P<0.05);观察组下床活动时间快于对照组(t=9.221,P<0.05),进食时间快于对照组(t=8.794,P<0.05),肛门恢复排气时间快于对照组(t=17.423,P<0.05),住院时间短于对照组(t=13.479,P<0.05),并发症发生率低于对照组(t=13.883,P<0.05);观察组术后1 d和3 d WBC水平均低于术前(t分别=7.277、26.911,P<0.05);观察组术后1 d和3 d WBC水平均低于同期对照组(t分别=3.6189、17.827,P<0.05);观察组术后3 d WBC水平低于术后1 d(t=20.732,P<0.05).结论腹腔镜阑尾切除术治疗急性阑尾炎患者临床疗效显著,是一种安全、有效的治疗方法,值得临床进一步研究.

关键词：腹腔镜阑尾炎切除术急性阑尾炎疗效安全性