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Chinese Journal of Structural Chemistry 2015年第6期34卷 899-905页

作者： HU Zhi-Yong zhu juan-juan CHEN Shui-Sheng QIAO Rui College of Chemistry & Chemical Engineering Fuyang Normal College

A new coordination polymer [Cd2（5-IPA）（HL）2（H20）2]＇4H20 （1） was prepared under hydrothermal conditions based on 5-hydroxy-isophthalic acid （5-H2IPA） with multi-N-donor ligand 1-（1H-imidazol-4-yl）-3-（4H-tetrazol-5-yl）benzene （H2L）. The complex was characterized by IR spectroscopy, TGA, X-ray powder and single-crystal diffraction. It crystallizes in the monoclinic system, space group C2/e with a = 23.6291（18）, b = 9.9847（8）, c = 17.7244（14） A, fl = 124.6180（10）°, V = 3441.4（5） A3, Z = 4, C28H30N12O11Cd2, Mr = 935.44, Dc = 1.805 g/cm^3,μ= 1.313 mm^-1, S = 1.055, F（000） = 1864, the final R = 0.049 and wR = 0.1315 for 2985 observed reflections （I 〉 2σ（I））. The central metal Cd（II） atoms with octahedral coordination geometry are six-coordinated by three oxygen and three nitrogen atoms. The HL- ligands from the deprotonated HzL connect Cd（II） atoms to form two-dimensional （2D） double-layer fes networks which are further pillared by 5-IPA2- ligands into a rare binodal （3, 4）-connected three-dimensional （3D） architecture with a （4·6·8）（4·62·83） fse-3,4-C2/c topology. Solid state luminescent property and sorption property of 1 have been investigated.

关键词： synthesis crystal structure luminescence property

Leaf Gas Exchange,Chlorophyll Fluorescence,and Fruit Yield in Hot Pepper (Capsicum anmuum L.) Grown Under Different Shade and Soil Moisture During the Fruit Growth Stage

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Journal of Integrative Agriculture 2012年第6期11卷 927-937页

作者： zhu juan-juan PENG Qiang LIANG Yin-li WU King HAO Wang-lin College of Life Sciences Northwest A&F University Yangling 712100 P.R.China Extension Center of Agricultural Technology Fengxian Agricultural Bureau Fengxian 721700 P.R.China Institute of Soil and Water Conservation the Chinese Academy of Sciences/Ministry of Water Resources Yangling 712100 P..R.China

Relative leaf chlorophyll （Chl.） content, leaf gas exchange, Chl. fluorescence, plant biological biomass, and fruit yield were evaluated in growing hot pepper （Capsicum annuum L.） during the fruit-growing stages in hot summer under three shade levels （un-shade, 30% shade, and 70% shade） and four soil water contents （SWC） of 40-55%, 55-70%, 70-85%, and 85- 100% of field moisture capacity （FMC）. Hot pepper crops were more affected by light irradiance than by soil moisture and by their interaction during the whole observed periods. Hot pepper attained greatest relative leaf Chl. content （expressed as SPAD value） and photosynthetic activity when cultivated with 30% shade, resulting in the highest plant biological biomass and fruit yield. Although 70% shade improved leaf photosynthetic efficiency （expressed as Fv/Fm or Fv＇/Fm＇）, crops obtained the lowest photosynthetic rate, photochemical quenching coefficient （qP）, and non-photochemical quenching coefficient （NPQ）. This showed that light irradiance was insufficiency in S70% （70% shade） treatment. The leaf net photosynthetic rates （PN）, Fc/Fm, and fruit yield increased gradually as SWC levels increased from 40-55% to 70- 85% FMC, but decreased as SWC was higher than 70-85% FMC. The water consumption increased progressively with SWC levels, but water-use efficiency （WUE） was the highest when soil moisture was 55-70% FMC. Interaction of shade and soil moisture had significant effects on PN and FJFm, but not on other parameters. Under drought stress （40-55% and 55-70% FMC）, 30% shade could relieve the droughty damage of crops and improve photosynthetic capacity and WUE, but 70% shade could not, oppositely, aggravate the damage. The positive correlation （r2 =0.72） between leaf PN and fruit yield was existent. This indicated that improvement of leaf photosynthesis would increase potentially marketable yield in hot pepper crops during the full fruit-growing stages. For agricultural purposes, approximately S30% （30% shade） with

关键词： leaf chlorophyll content photosynthetic capacity interaction

Sequence-activated chemiluminescence probes:programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao Zhang juan Li Wei-Hong zhu Zhiqian Guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular EngineeringInstitute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science&TechnologyShanghai 200237China

Sequence-activated chemiluminescence(CL)technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial *** fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest,thus enabling high-contrast signals under complex physiological *** sequential activation could be triggered by enzymes,reactive oxygen species(ROS),biothiols or changes in the *** unique sequence-activated CL probes bestow several advantages,including minimal background,deep-tissue penetration,and the ability of non-invasive or minimally invasive *** sequence-activated CL techniques represent a significant advancement in molecular imaging and *** this mini-review,we focus on the latest developments in sequential CL probes,addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

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复杂场景中基于变块差分的运动目标检测

光学精密工程 2011年第1期19卷 183-191页

作者：朱娟娟郭宝龙西安电子科技大学机电工程学院陕西西安710071

针对复杂场景中包含的摄像机扫描运动、随机抖动和目标运动,提出一种基于帧间可变块差分的运动目标检测算法。首先,利用全局特征点估计运动参数对帧间背景进行补偿,提取图像的全局特征点并匹配,以特征点集的最小位置误差和作为目标进行... 详细信息

针对复杂场景中包含的摄像机扫描运动、随机抖动和目标运动,提出一种基于帧间可变块差分的运动目标检测算法。首先,利用全局特征点估计运动参数对帧间背景进行补偿,提取图像的全局特征点并匹配,以特征点集的最小位置误差和作为目标进行迭代,获取误差不大于0.5 pixel的全局运动参数,并精确补偿当前帧实现背景校正。然后,利用可变块差分实现运动目标的检测。先用大尺寸对差分图像进行分割,将整幅图像粗略区分为背景区域、运动目标区域和边界区域,通过阈值判定来进一步细分,最后对运动目标区域进行准确标定。这种由粗到细的检测步骤,在保证精度的同时能够提高检测速度。实验结果表明,该算法能够准确检测含摄像机扫描和抖动的复杂运动场景中的前景运动目标,且处理速度达到25 frame/s。

关键词：视频图像运动目标检测可变块差分全局运动估计帧间补偿

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一种鲁棒的电子稳像系统

西安电子科技大学学报 2007年第3期34卷 418-422,452页

作者：朱娟娟郭宝龙西安电子科技大学机电工程学院陕西西安710071

基于特征点跟踪的全局运动估计和利用Kalman滤波的运动补偿,提出一种鲁棒的电子稳像系统.首先,提取特征点的局部信息以估计全局运动,其中各特征点的跟踪是通过特征窗匹配来完成的,同时根据特征点集间具有稳定相对位置的结构特征,提出距... 详细信息

基于特征点跟踪的全局运动估计和利用Kalman滤波的运动补偿,提出一种鲁棒的电子稳像系统.首先,提取特征点的局部信息以估计全局运动,其中各特征点的跟踪是通过特征窗匹配来完成的,同时根据特征点集间具有稳定相对位置的结构特征,提出距离准则,对特征匹配进行验证,来去除前景运动点或误匹配点(即局部特征点).然后,将所有验证后的匹配点对(全局特征点)带入运动模型,并利用Levenberg-Marquardt进行最优化迭代,求出全局运动矢量.最后,对原始运动矢量序列进行Kalman滤波,提取抖动参数以补偿图像.实验结果表明,该系统可以处理图像序列的平移、旋转和缩放等抖动,并且对于场景中的局部运动有良好的鲁棒性.

关键词：电子稳像全局运动估计 Kalman滤波特征点

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一种运动载体摄像的自适应稳像系统

光电子．激光 2007年第1期18卷 108-112页

作者：朱娟娟郭宝龙西安电子科技大学机电工程学院 ICIE研究所陕西西安710071

提出一种达到实时处理能力的自适应电子稳像系统。首先,采用基于投影相关单峰性的配准策略进行全局运动估计,为了减小投影全相关计算的复杂度,提出了快速投影算法(FPA),采用3点自适应搜索策略,结合大小搜索步长,进行由粗到细的搜索定位... 详细信息

提出一种达到实时处理能力的自适应电子稳像系统。首先,采用基于投影相关单峰性的配准策略进行全局运动估计,为了减小投影全相关计算的复杂度,提出了快速投影算法(FPA),采用3点自适应搜索策略,结合大小搜索步长,进行由粗到细的搜索定位。其次,详细阐述了自适应均值滤波方法,通过自适应调整滑动窗口的尺寸,实现较好的平滑处理以降低抖动,并防止了过稳现象的发生。最后,提出运动矢量修正措施,以自适应地选取待补偿帧,来防止图像边缘的错误累积效应。实验结果表明,该系统可以明显减轻视频序列抖动现象,而且能实时跟随真实扫描场景。

关键词：电子稳像灰度投影算法运动估计运动补偿

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基于联合双边滤波的单幅图像去雾算法

北京邮电大学学报 2012年第4期35卷 19-23页

作者：陈龙郭宝龙毕娟朱娟娟西安电子科技大学智能控制与图像处理研究所西安710071

针对在烟、雾、霾等恶劣的户外条件下,由于大气粒子的散射作用导致捕获的景物图像严重退化的问题.本文提出一种新的单幅图像去雾算法,该算法从大气散射模型出发,首先对降质图像进行白平衡,从而简化了大气散射模型;然后利用非线性空间滤... 详细信息

针对在烟、雾、霾等恶劣的户外条件下,由于大气粒子的散射作用导致捕获的景物图像严重退化的问题.本文提出一种新的单幅图像去雾算法,该算法从大气散射模型出发,首先对降质图像进行白平衡,从而简化了大气散射模型;然后利用非线性空间滤波方法估计粗糙的大气幕亮度,用联合双边滤波方法进一步细化大气幕亮度;最后采用色度调和得到恢复图像.该算法的时间复杂度是图像像素的线性函数,运算速度较快.试验结果表明,该算法有效地恢复了场景的对比度和颜色,从而明显地提高了图像的视见度.

关键词：图像去雾联合双边滤波大气散射模型白平衡色度调和

Barrierless reactions of C2 Criegee intermediates with H_(2)SO_(4)and their implication to oligomers and new particle formation

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Journal of Environmental Sciences 2025年第3期149卷 574-584页

作者： Yang Cheng Chao Ding Tianlei Zhang Rui Wang Ruxue Mu Zeyao Li Rongrong Li juan Shi Chongqin zhu Institute of Theoretical and Computational Chemistry Shaanxi Key Laboratory of CatalysisSchool of Chemical&Environment ScienceShaanxi University of TechnologyHanzhongShaanxi 723001China College of Chemistry Key Laboratory of Theoretical&Computational Photochemistry of Ministry of EducationBeijing Normal UniversityBeijing 100190China

The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol(SOA).However,to date,the reactivity of C2 Criegee intermediates(CH_(3)CHOO)in areas contaminated with acidic gas remains poorly ***,high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics(BOMD)simulations are used to explore the reaction of CH_(3)CHOO and H_(2)SO_(4)both in the gas phase and at the airwater *** the gas phase,the addition reaction of CH_(3)CHOO with H_(2)SO_(4)to generate CH_(3)HC(OOH)OSO_(3)H(HPES)is near-barrierless,regardless of the presence of water *** simulations showthat the reaction at the air-water interface is even faster than that in the gas *** calculations reveal that the HPES has a tendency to aggregate with sulfuric acids,ammonias,and water molecules to form stable clusters,meanwhile the oligomerization reaction of CH_(3)CHOO with HPES in the gas phase is both thermochemically and kinetically ***,it is noted that the interfacial HPES−ion can attract H_(2)SO_(4),NH_(3),(COOH)_(2)and HNO_(3)for particle formation from the gas phase to the water ***,the results of this work not only elucidate the high atmospheric reactivity of C2 Criegee intermediates in polluted regions,but also deepen our understanding of the formation process of atmospheric SOA induced by Criegee intermediates.

关键词： Criegee intermediates H_(2)SO_(4) Atmospheric behavior Air-water interface Chemical processes

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抗前景干扰的自适应电子稳像算法

光子学报 2015年第6期44卷 45-52页

作者：朱娟娟范静郭宝龙西安电子科技大学空间科学与技术学院

针对场景中存在前景目标运动的抖动视频,提出一种抗前景干扰的自适应电子稳像算法.算法以视觉对运动的感知为指导,采用基于块的三帧间差分,利用时空一致性快速剔除运动前景区域;改进传统Harris算子,用网格筛选和显著度排序,对背景区域... 详细信息

针对场景中存在前景目标运动的抖动视频,提出一种抗前景干扰的自适应电子稳像算法.算法以视觉对运动的感知为指导,采用基于块的三帧间差分,利用时空一致性快速剔除运动前景区域;改进传统Harris算子,用网格筛选和显著度排序,对背景区域进行全局显著特征点的提取和配准,保证全局配准准确度;用统计分布的距离准则去除误匹配点,无需特征点迭代运算,提高了全局运动估计的速度和准确度.在Sage-Husa自适应运动滤波方法的基础上,改进了修正过程噪音和观测噪音的统计特性,模拟摄像机低频匀速运动的视觉平滑效果,有效解决摄像机抖动中存在的扫描运动.在Intel酷睿2四核2.33GHz的微机上用VC++进行实验,结果表明,该算法对320×240像素的视频序列能够达到22fps的处理能力,可以实时稳定含较大或多运动前景目标的复杂抖动视频,输出视觉完整流畅的真实扫描场景.

关键词：视频信息处理电子稳像全局运动估计自适应运动滤波运动补偿 Harris算子峰值信噪比

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基质力学微环境对血管平滑肌细胞功能的影响

生理学报 2021年第2期73卷 160-174页

作者：王谨朱娟娟周菁北京大学基础医学院生理学与病理生理学系北京100191 教育部分子心血管重点实验室北京100191 国家卫生健康委员会心血管分子生物学与调节肽重点实验室北京100191

血管平滑肌细胞是血管壁中的主要细胞类型,处于复杂的基质微环境中。微环境中的力学因素(包括基质刚度、基质微纳拓扑结构以及基质对细胞的几何约束等)可影响平滑肌细胞表型与功能。平滑肌细胞通过特定的机械力感受器感知基质微环境中... 详细信息

血管平滑肌细胞是血管壁中的主要细胞类型,处于复杂的基质微环境中。微环境中的力学因素(包括基质刚度、基质微纳拓扑结构以及基质对细胞的几何约束等)可影响平滑肌细胞表型与功能。平滑肌细胞通过特定的机械力感受器感知基质微环境中的机械力刺激,并将机械信号转化为生物化学信号,调控下游基因表达与活性,从而影响平滑肌细胞的各种行为。血管平滑肌细胞行为的异常可破坏血管稳态,导致血管重塑。阐明平滑肌细胞如何感知与传导机械力刺激以及细胞外力学微环境如何调控平滑肌细胞的表型与功能,可为血管疾病的预防与治疗提供新的策略。

关键词：血管平滑肌细胞细胞外基质机械力感受器机械信号转导血管重塑