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Engineering molecular self-assembly of theranostic nanoprobes for dual-modal imaging-guided precise chemotherapy

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Science China Chemistry 2021年第11期64卷 2045-2052页

作者： Chenxu Yan Hongxia Xu Menglan Wu Zijun zhao weijun zhao Jianbin Tang Zhiqian Guo Key Laboratory for Advanced Materials and Institute of Fine Chemicals Joint International Research Laboratory of Precision Chemistry and Molecular EngineeringFeringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory of Biomass Chemical Engineering of Ministry of Education Center for Bionanoengineeringand Department of Chemical and Biological EngineeringZhejiang UniversityHangzhou310027China

Uniting dual-modality of fluorescence and photoacoustic(PA)imaging into theranostic nanoprobes is imperative for spatiotemporally tracking of drug delivery,distribution,and ***,we present a rational design strategy of molecularly precise amphiphilic prodrugs BP_(n)-Cy-S-CPT(n=0,5,and 20,refers to the degree of polyethylene glycol(PEG)polymerization;CPT=camptothecin)to tune their self-assembly behaviour,innovatively integrating dual-modal PA and near-infrared(NIR)fluorescence imaging in a single-molecular *** these elaborately designed prodrugs,it is found that only BP_(20)-Cy-S-CPT could form uniform and highly stable self-assemblies,especially in showing synergistically enhanced PA and dualchannel NIR *** detail,PA signal is employed to trace the in vivo delivery with high spatial resolution,meanwhile the glutathione(GSH)-triggered dual-channel fluorescence response could real-timely monitor drug distribution and release without"blind spot".The results of in vivo dual-modal PA/NIR imaging have verified that BP_(20)-Cy-S-CPT displayed synergistic targeting(including passive,active,and activatable targeting)for tumor-specific delivery,and thereby executed CPT release in the tumor ***,our molecularly precise BP_(20)-Cy-S-CPT self-assemblies could make a breakthrough to spatiotemporally track the in vivo drug release profile,expanding the intelligent theranostic toolbox for precise cancer treatment.

关键词： fluorescence probe near-infrared fluorescence probe photoacoustic imaging self-assembly prodrug

基于地球物理数据融合的大兴安岭中段东缘地壳结构研究

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地质学报 2024年第7期98卷 2064-2083页

作者：赵维俊秦涛李建平肖锋韩江涛荣幸郭宝东葛欢牛兴国中国地质调查局沈阳地质调查中心辽宁沈阳110034 中国地质调查局广州海洋地质调查局广东广州510075 吉林大学地球探测科学与技术学院吉林长春130026 山西省地质调查院有限公司山西太原030006 辽宁省物测勘查院有限责任公司辽宁沈阳110032 中煤科工集团沈阳研究院有限公司辽宁沈抚示范区113122 内蒙古有色地质矿业(集团)物探勘查有限责任公司内蒙古呼和浩特010010

位于中亚造山带东段的兴安地块和松辽锡林浩特地块被晚古生代贺根山-黑河缝合带分开。随后,大兴安岭与松辽盆地被中新生代嫩江-八里罕断裂分开。在大兴安岭中段,这两构造带的位置及板块拼合时间尚不明确。为研究大兴安岭中段东缘重要构... 详细信息

位于中亚造山带东段的兴安地块和松辽锡林浩特地块被晚古生代贺根山-黑河缝合带分开。随后,大兴安岭与松辽盆地被中新生代嫩江-八里罕断裂分开。在大兴安岭中段,这两构造带的位置及板块拼合时间尚不明确。为研究大兴安岭中段东缘重要构造断裂、构造单元及结晶基底属性特征,在扎兰屯-阿荣旗地区采集处理一条长60 km的重力、磁法和大地电磁数据,重新处理了1:20万扎兰屯幅、阿荣旗幅区域布格重力异常数据。通过多种地球物理数据融合,解译了7条重要断裂,其中庞家街断裂和红星断裂是控制贺根山-黑河缝合带的深大断裂。北西向阿伦河断裂为深大断裂,至少切割到中地壳。发现了两个中地壳低阻带,其中C2异常解释为贺根山-黑河缝合带。通过1:25万阿荣旗幅地质填图资料,证实了地球物理数据融合的推断结果,为大兴安岭中段东缘构造带演化研究提供了重要支撑。

关键词：贺根山-黑河缝合带嫩江断裂兴安地块松嫩地块大地电磁重力磁法数据融合

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球形储罐支柱检验方法应用

西部特种设备 2024年第4期7卷 35-40页

作者：杨磊赵博赵伟军魏波王超牛犇西安兵器工业特种设备检测有限责任公司陕西西安710043

球形储罐是我国化工企业常用的一种储存容器,大多用来储存易燃易爆、有毒有害的气体、液体、液化气体。支柱检验是球形储罐定期检验的一项重要内容,利用渗透检测、磁粉检测对支柱与球壳板角焊缝表面进行无损探伤,同时结合支柱沉降度检... 详细信息

球形储罐是我国化工企业常用的一种储存容器,大多用来储存易燃易爆、有毒有害的气体、液体、液化气体。支柱检验是球形储罐定期检验的一项重要内容,利用渗透检测、磁粉检测对支柱与球壳板角焊缝表面进行无损探伤,同时结合支柱沉降度检查和支柱垂直度检查能很好地检验球罐支柱安全状况,排除安全隐患。

关键词：球形储罐检验支柱安全状况

祁连山排露沟流域青海云杉天然更新空间关联性研究

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干旱区资源与环境 2024年第1期38卷 161-170页

作者：刘济萌刘贤德马瑞赵维俊敬文茂拓锋王艳霞甘肃农业大学林学院兰州730070 甘肃省祁连山水源涵养林研究院(甘肃祁连山森林生态系统国家定位观测研究站) 张掖734000 兰州大学草地农业科技学院兰州730000

青海云杉作为祁连山森林生态的建群种,其天然更新的空间关联性及集聚模式对种群更新具有重要意义。于2022年8月对祁连山排露沟流域海拔2800-3300m样地内的青海云杉林进行每木检尺,研究将胸径小于50mm的青海云杉植株划为更新苗,并选取更... 详细信息

青海云杉作为祁连山森林生态的建群种,其天然更新的空间关联性及集聚模式对种群更新具有重要意义。于2022年8月对祁连山排露沟流域海拔2800-3300m样地内的青海云杉林进行每木检尺,研究将胸径小于50mm的青海云杉植株划为更新苗,并选取更新苗胸径、株高两个生物指标,通过空间自相关分析探究其胸径、株高的空间关联性及集聚模式。结果表明:1)不同海拔更新苗胸径、株高均表现为空间正自相关,胸径空间关联性呈现为2800m>3100m>3000m>2900m>3300m,株高空间关联性呈现为2800m>2900m>3100m>3000m>3300m,仅3200m样地胸径和株高均表现为不显著的空间负自相关,表明更新苗胸径和株高的空间关联性随着海拔的升高而逐渐降低。2)不同样地更新苗胸径和株高个体间空间正自相关的数量远多于空间负自相关,表明青海云杉更新个体的生长有益于邻近径级个体的生长。3)更新苗胸径和株高整体呈现为低低集聚比高高集聚更为集中,且相互间分界明显,表明邻近径级的植株间关系较为协调,径级差异较大的植株间排斥效应较为明显。4)更新苗胸径和株高均表现出高高集聚和低低集聚交替分布的现象,且随着海拔的升高,高高集聚现象逐渐消失。

关键词：青海云杉天然更新空间自相关空间集聚

Photoresponsive aggregation-induced emission polymer film for anti-counterfeiting

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Chinese Chemical Letters 2021年第12期32卷 3882-3885页

作者： Hong Yang Mengqi Li weijun zhao Zhiqian Guo Wei-Hong Zhu Shanghai Key Laboratory of Functional Materials Chemistry Key Laboratory for Advanced Materials and Institute of Fine Chemicals.Joint International Research Laboratory of Precision Chemistry and Molecular EngineeringFeringa Nobel Prize Scientist Joint Research CenterSchool of Chemistry and Molecular EngineeringEast China University of Science&TechnologyShanghai 200237China

The development of solid-state smart materials, in particular those showing photoresponsive luminescence, is highly desirable for their cutting edge applications in displays, sensors, data-storage, and anticounterfeiting. However, to achieve both excellent photoresponsive performance and bright luminescence in solid state remains challenge. Herein, we integrate a novel photochromic fluorophore YL into flexible polymer chains, thereby enabling the resultant polymer PYL with reversible photoisomerization upon aggregation. Remarkably, the polymer PYL possesses excellent photochromic properties and aggregationinduced emission(AIE) activity, which can be attributed to the photoactive YL moiety. Upon light exposure, its film exhibits reversibly off-to-on fluorescent modulation with quick response, high emission efficiency and signal contrast, sharply different from the weak emission in solution. The novel photoresponsive AIE polymer with invisible/visible color and fluorescence transformation allows for advanced anti-counterfeiting applications. This work provides an efficient platform for constructing solid-state photocontrollable luminescent materials.

关键词： Aggregation-induced emission Photoresponsive luminescence Diarylethene Photochromism Polymer film Anti-counterfeiting

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基于细节显著性估计的低照度图像增强方法

红外技术 2024年第10期46卷 1145-1153页

作者：杨锋赵维骏顾燕董隽媛吕扬李海生郭一亮朱波北方夜视科技(南京)研究院有限公司江苏南京211102

在基于Retinex分解的低照度图像增强算法中,通过同时估计反射层和亮度层进行反射层恢复是一种流行且有效的方法,但算法结构较为复杂,实现难度大。这是因为恢复反射率是一个约束优化问题,不能用简单的优化技术来解决。本文提出了一种细... 详细信息

在基于Retinex分解的低照度图像增强算法中,通过同时估计反射层和亮度层进行反射层恢复是一种流行且有效的方法,但算法结构较为复杂,实现难度大。这是因为恢复反射率是一个约束优化问题,不能用简单的优化技术来解决。本文提出了一种细节显著性估计方法,可以利用简单的梯度下降优化技术从图像中恢复出反射层。该方法是基于我们所提出假设——暗区域近似(dark region approximation,DRA):由于低照度图像暗区域中的光照很弱,因此将其忽略不计,即将输入图像中暗区域的灰度分布直接近似为反射层。首先利用高斯场准则构建目标函数,通过基于DRA的Retinex模型估计细节显著层;然后用拟牛顿法求解该无约束优化问题;最后,从细节显著层中恢复出反射层作为最终增强结果。实验结果表明,与现有同类方法相比,我们的方法在增强效果和计算效率方面都具有优势。

关键词：灰度增强低照度图像反射率估计 Retinex模型

Spatial patterns of Picea crassifolia driven by environmental heterogeneity and intraspecifi c interactions

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Journal of Forestry Research 2023年第4期34卷 949-962页

作者： Changxing zhao weijun zhao Ming Jin Jiqiang Zhou Feng Ta Lei Wang Wenbo Mou Longju Lei Jinrong Liu Junlin Du Xinglin Zhang State Key Laboratory of Grassland Agro-Ecosystems College of Pastoral Agriculture Scienceand TechnologyLanzhou UniversityLanzhou 730000People’s Republic of China Academy of Water Resources Conservation Forests in Qilian Mountains of Gansu Province Zhangye 734000People’s Republic of China Gansu Nonferrous Engineering Survey Design and Research InstituteLanzhou 730000People’s Republic of China State Key Laboratory of Grassland Agro-Ecosystems School of Life ScienceLanzhou UniversityLanzhou 730000People’s Republic of China Hexi University Zhangye 734000People’s Republic of China Gansu Academy of Eco-Environmental Sciences Lanzhou 730030People’s Republic of China

Research on the spatial patterns of tree populations is critical for understanding the structure and dynamic processes of ***,little is known about how the underlying drivers shape these patterns and species interactions in forest *** this study,spatial point pattern analysis investigated the combined eff ects of intraspecifi c interactions and environmental heterogeneity on the spatial structure and internal maintenance mechanisms of Picea crassifolia in the Qilian Mountain National Nature Reserve,*** were obtained from a 10.2-ha dynamic monitoring plot(DMP)and sixteen 0.04-ha elevation gradient plots(EGPs).Under complete spatial randomness,both mature trees and saplings in the DMP demonstratedlarge-scale aggregation with negative *** EGPs,saplings were clustered in small mesoscales,mature trees were randomly distributed,and the interactions of saplingstrees at all elevations were not *** eliminating the interference of environmental heterogeneity through the inhomogeneous Poisson process,saplings in the DMP and EGPs were clustered in small scales and trees randomly *** c associations were negatively correlated,in the DMP and at low elevations,and no correlations in high elevations of *** the vertical scale,saplings showed a small-scale aggregation pattern with increase in elevation,and the aggregation degree fi rst decreased and then *** interactions of saplings-trees and saplings–saplings showed inhibitions at small scales,with the degree of inhibition gradually *** patterns and associations of adults–adults did not change *** results revealed that intraspecifi c interactions and environmental heterogeneity regulated the spatial patterns of *** at small and large scales,*** heterogeneity might be the most decisive factor aff ecting the spatial patterns of saplings,while trees were more aff ected by intraspecifi c intera

关键词： Picea crassifolia Spatial point pattern analysis Intraspecifi c interactions Environmental heterogeneity

Effects of microtopography on spatial point pattern of forest stands on the semi-arid Loess Plateau,China

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Journal of Arid Land 2015年第3期7卷 370-380页

作者： weijun zhao Yan ZHANG QingKe ZHU Wei QIN ShuZhen PENG Ping LI YanMin zhao Huan MA Yu WANG Key Laboratory of Tourist Resources and Environment in Colleges and Universities of Shandong Province Taishan University Forestry Ecological Engineering Research Center (Ministry of Education) Beijing Forestry University Department of Sedimentation China Institute of Water Resources and Hydropower Research Key Laboratory of Forest Ecology and Environment of State Forestry Administration Institute of Forest EcologyEnvironment and ProtectionChinese Academy of Forestry

Microtopography may affect the distribution of forests through its effect on rain redistribution and soil water distribution on the semi-arid Loess Plateau,*** this study,we investigated the characteristics of microtopography on two shady slopes（slope A,5 hm2,uniform slope;slope B,5 hm2,microtopography slope） and surveyed the height,the diameter at breast height and the location（x,y coordinates） of all selected individual trees（Robinia pseudoacacia Linn.,Pyrus betulifolia Bunge,Populus hopeiensis Hu ＆ Chow,Armeniaca sibirica Lam.,Populus simonii *** Ulmus pumila Linn.） on slope A and slope B in the watersheds of Wuqi county,Shaanxi ***,the effects of microtopography on the spatial pattern of forest stands were analyzed using Ripley＇s K（r） *** results showed that：（1） The maximal aggregation radiuses of the tree species on the uniform slope（slope A） were larger than 40 m,whereas those of the tree species on the microtopography slope（slope B） were smaller than 30 m.（2） On slope B,the spatial association of *** with ***,***,*** and *** varied from being strongly negative to positive at microtopography *** spatial association of Populus hopeiensis Hu ＆ Chow with *** also varied from being strongly negative to positive at microtopography ***,there was no spatial association between *** and ***,*** and ***,*** and ***,*** and ***,*** and ***,*** and ***,*** and ***,*** and ***,and *** and *** slope A,the spatial association between tree species were strongly *** results suggest that microtopography may shape tree distribution patterns on the semi-arid Loess Plateau.

关键词： microtopography univariate spatial patterns aggregation negative association positive association

Type I photosensitizer based on AIE chromophore tricyano-methylene-pyridine for photodynamic therapy

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Green Chemical Engineering 2023年第3期4卷 324-330页

作者： Chao Pan weijun zhao Xiaolei zhao Zhenxing Liu Xiangyu Li Yanting Lyu Xupeng Wu Zhirong Zhu Wei-Hong Zhu Qi Wang Shanghai Key Laboratory of Functional Materials Chemistry Key Laboratory for Advanced Materials and Institute of Fine ChemicalsJoint International Research Laboratory of Precision Chemistry and Molecular EngineeringFeringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistrySchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai200237China

Image guided photodynamic therapy(PDT)combines fluorescence tracing and phototherapy,which can achieve a more accurate and effective treatment ***,traditional photosensitizers are limited by the aggregation-caused fluorescence quenching(ACQ)effect and low reactive oxygen species(ROS)generation in a hypoxic environment,resulting in poor imaging and treatment ***,we report a tricyano-methylene-pyridine(TCM)-based Type I aggregation-induced emission(AIE)photosensitizer(TCM-MBP),the strong elec-tron acceptance(D-A)effect extends the wavelength to near-infrared(NIR)region to reduce the autofluorescence interference,and oxygen atoms provide lone pair electrons to enhance the inter system crossing(ISC)rate,thereby promoting the generation of more triplet states to produce *** AIE photosensitizer TCM-MBP exhibited low oxygen dependence,NIR emission,and higher ROS production compared to commercially avail-able Ce_(6) and *** encapsulation with DSPE-PEG 2000,TCM-MBP nanoparticles(TCM-MBP NPs)could penetrate to visualize cells and efficiently kill cancer cells upon light *** study provides an oxygen-independent AIE photosensitizer,which has great potential to replace the commercial ACQ photosensitizers.

关键词： Aggregation-induced emission Near-infrared emission Photodynamic therapy Type I ROS