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Catalyst-free 2+2 Photodimerization of l,4-Bis[2-(4-pyridyl)ethenyl]-benzene in Solution Under Low Power UV Irradiation

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Chemical Research in Chinese Universities 2020年第5期36卷 816-820页

作者： CHU Ning xu shuping xu Weiqing State Key Laboratory of Supramolecular Structure and Materials Jilin UniversityChangchun 130012P.R.China

Two different kinds of configurations of 1,4-bis[2-(4-pyridyl)etheny 1]-benzene(trans-bpeb and c/5-bpeb)were achieved,and a bpeb dimer was synthesized in dimethyl sulfoxide(DMSO).Compared with the previous work that synthesized the bpeb dimer or polymer in crystal with a template agent needed,the reaction occurred in a solu・tion phase in the present method.A hand-held ultraviolet lamp(365 nm)with the power of 12 W and the Watt density of 0.35 mW/cm2 can realize the photodimerization of bpeb,instead of the high-power mercury lamp in most previous *** other 2+2 cycloaddition in liquid state using catalysts even noble metals,no catalysts were required here,which is *** the trans-pbeb can start the cycloaddition and the formation of the close J-aggregations of Zra≪5-pbeb in DMSO is a precondition for explaining the 2+2 *** productivity for the 2+2 cycloaddition product was achieved as 55.6%.

关键词： 2+2 Photodimerization 1,4-Bis[2-(4-pyridyl)ethenyl]-benzene Catalyst-free

Surface-state triggered solvatochromism of carbonized polymer dot and its two-photon luminescence

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Nano Research 2022年第3期15卷 2567-2575页

作者： Zepeng Huo Weiqing xu Gang Chen Zizhun Wang shuping xu State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun130012China Electron Microscopy Center Jilin UniversityChangchun130012China

This study reports a new nitrogen-doped carbonized polymer dot(CPD)-based solvatochromic *** color-changing for different solvents was explored in detail by the measurements of photophysical parameters(involving Stokes shifts,fluorescence quantum yield,fluorescence lifetime,radiative decay rate constant,and non-radiative decay rate constant)and the following analyses according to Lippert–Mataga equation and Kamlet–Taft *** hydrogen bonding effect of the CPD in protonic solvents was semi-quantitatively *** takes charge of the solvatochromic phenomenon,especially in proton ***,this CPD exhibits two-photon ***,the relations between the photophysical parameters and the surface states of CPD in aprotic and proton solvents were *** results reveal the nitrogen doping in the CPD impacts the up-and down-conversion solvatochromic features from the comparison between N-free and N-doped CPDs in many *** addition,this N-doped CPD was dispersed into polymer matrices to fabricate tunable solid-state luminescent films,which is another model for evidencing the interactions of the CPD with *** study is of significance in understanding the surface-state controlled luminescence in the CPDs,and will be beneficial for developing new smart,responsive carbon-based nanoprobes.

关键词： carbon dots carbonized polymer dots solvatochromism two-photon fluorescence solid-state luminescence

内蒙古乌拉特中旗284东金矿控矿断裂系统及找矿方向

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矿业工程 2024年第4期22卷 1-5,9页

作者：汪瑞强汪涌佳徐述平巴彦淖尔市应急管理局内蒙古巴彦淖尔015000 乌拉特中旗保利矿业股份有限公司284东金矿内蒙古巴彦淖尔015000

284东金矿是近几年发现的蚀变岩型金矿床,位于内蒙古宝音图金镍铜铁锰等多金属成矿带,赋存于区域性F9断裂与华力西晚期石英闪长岩体断层接触带。F9断裂早期表现为大规模韧性剪切带,后期脆性变形叠加,其与上下盘次级断裂共同组成了金矿... 详细信息

284东金矿是近几年发现的蚀变岩型金矿床,位于内蒙古宝音图金镍铜铁锰等多金属成矿带,赋存于区域性F9断裂与华力西晚期石英闪长岩体断层接触带。F9断裂早期表现为大规模韧性剪切带,后期脆性变形叠加,其与上下盘次级断裂共同组成了金矿控矿断裂系统,主断裂控制了矿区主矿体的规模、形态、产状,上下盘次级断裂和节理裂隙控制了矿区次级矿体的展布及矿化富集,主次断裂“y”字形交汇部位产出金矿床。在分析控矿断裂系统的基础上,指出下步找矿方向主要是已知矿床深部及主次断裂“y”字形交汇部位。

关键词： 284东金矿控矿断裂系统找矿方向

Modulation of hot regions in waveguide-based evanescent-field-coupled localized surface plasmons for plasmon-enhanced spectroscopy

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Photonics Research 2017年第5期5卷 518-526页

作者： HAILONG WANG YUYANG WANG YI WANG WEIQING xu shuping xu State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical Chemistry Jilin University

Coupling efficiency between the localized surface plasmons(LSPs) of metal nanoparticles(NPs) and incident light dominates the sensitivities of plasmon-based sensing spectroscopies and imaging techniques, e.g., surfaceenhanced Raman scattering(SERS) spectroscopy. Many endogenous features of metal NPs(e.g., size, shape,aggregation form, etc.) that have strong impacts on their LSPs have been discussed in detail in previous ***, the polarization-tuned electromagnetic(EM) field that facilitates the LSP coupling is fully *** analyses on waveguide-based evanescent fields(WEFs) coupled with the LSPs of dispersed silver nanospheres and silver nano-hemispheres are presented and the applicability of the WEF-LSPs to plasmon-enhanced spectroscopy is discussed. Compared with LSPs under direct light excitation that only provide 3–4 times enhancement of the incidence field, the WEF-LSPs can amplify the electric field intensity about 30–90 times(equaling the enhancement factor of 10~6–10~8 in SERS intensity), which is comparable to the EM amplification of the SERS"hot spot" effect. Importantly, the strongest region of EM enhancement around silver nanospheres can be modulated from the gap region to the side surface simply by switching the incident polarization from TM to TE, which widely extends its sensing applications in surface analysis of monolayer of molecule and macromolecule detections. This technique provides us a unique way to achieve remarkable signal gains in many plasmon-enhanced spectroscopic systems in which LSPs are involved.

关键词： NP Ag Modulation of hot regions in waveguide-based evanescent-field-coupled localized surface plasmons for plasmon-enhanced spectroscopy WEF

Preparation of Surface-enhanced Raman Scattering（SERS）-active Optical Fiber Sensor by Laser-induced Ag Deposition and Its Application in Bioidentification of Biotin/Avidin

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Chemical Research in Chinese Universities 2015年第1期31卷 25-30页

作者： LIU Chunyu WANG Shaoyan FU Cuicui LI Haibo xu shuping xu Weiqing State Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical Chemistry Jilin University Changchun 130012 R R. China College of Science Changchun University of Science and Technology Changchun 130022 P. R. China

A surface-enhanced Raman scattering（SERS） optical fiber sensor was prepared by the laser-induced deposition ofAg nanoparticle membrane on a silica optical fiber tip, which was applied to the real time SERS spectral monitoring on the biorecognition of biotin/avidin. The bioidentification of biotin/avidin was carried out through a indirect method, in which the bioidentification is based on the SERS response signal of a labeled dye（Atto610） after its fluorescence has been quenched totally by the deposited Ag nanoparticle membrane. By SERS monitoring the bioidentification process of biotin/avidin, it has been found that this recognition process is finished in 40 min. The lowest detection concentration of biotin is 1.0 × 10^-7 mg/mL. This research is promising in the application of immunoassays on line and in vivo.

关键词： Process monitoring Photochemical method Laser-inducement SERS-active optical fiber Biotin/avidin Specific identification

Quantitative Determination of Urine Glucose： Combination of Laminar Flow in Microfluidic Chip with SERS Probe Technique

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Chemical Research in Chinese Universities 2018年第6期34卷 899-904页

作者： SUN Dan LIU Xiangyuan xu shuping TIAN Yu xu Weiqing TAO Yanchun Key Laboratory of Supramolecular Structure and Materials Institute of Theoretical Chemistry Jilin Universiry Changehun 130012 P. R. China

A surface-enhanced Raman scattering（SERS） sensing approach for urine glucose was developed based on the laminar flow technology in a cross-type microfluidic chip with SERS probes, 4-mercaptophenylboronic acid （MPBA） functionalized Ag nanoparticles. MPBA as the glucose receptor can identify and bind up with glucose at a molar ratio of 2：1, which can cause the aggregation of SERS probes at a certain position of the chip channel and further enhance the SERS signal of MPBA significantly. Thus, the quantitative SERS detection of glucose was achieved indirectly. No sample pretreatment and separation were needed in this method since the SERS detection was achieved in the gradient diffusion and molecular recognition processes between urine glucose and SERS probe in the laminar flow, which simplified the sample treahnent procedures, saved detection time and made it feasible for clinic applications. This method shows a good linear relationship within human body＇s normal physiological range and has high sensitivity and selectivity： The lowest detection concentration can reach 1.0 mg/dL.

关键词： Surface-enhanced Raman scattefing(SERS) Microfluidic chip 4-Mercaptophenylboronic acid Uurine glucose

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多传感器融合的室内机器人SLAM

西安工业大学学报 2024年第1期44卷 93-103页

作者：徐淑萍杨定哲熊小墩西安工业大学计算机科学与工程学院西安710021

为了解决基于二维激光雷达的SLAM在室内环境中存在定位误差较大和建图不完善的问题,提出一种多传感器融合的室内机器人SLAM算法。该算法针对传统ICP算法在激光SLAM前端存在误匹配问题,采用更适合室内环境的PL-ICP算法,并利用扩展卡尔曼... 详细信息

为了解决基于二维激光雷达的SLAM在室内环境中存在定位误差较大和建图不完善的问题,提出一种多传感器融合的室内机器人SLAM算法。该算法针对传统ICP算法在激光SLAM前端存在误匹配问题,采用更适合室内环境的PL-ICP算法,并利用扩展卡尔曼滤波融合轮式里程计和IMU为其提供初始的运动估计值。在建图阶段利用深度相机获取的三维点云数据转化的伪二维激光数据和二维激光雷达获取的数据进行融合,弥补二维激光雷达建图没有垂直方向视野的缺陷。实验结果表明:融合里程计数据相比于单一轮式里程计定位精度至少提升了33%,为PL-ICP算法提供了更高精度的初始迭代值。同时融合建图弥补了单一二维激光雷达建图的缺陷,构建了环境信息更加完善的环境地图。

关键词：同步定位与建图室内机器人扩展卡尔曼滤波 PL-ICP算法

新能源背景下对锂矿资源开发利用的“理性思考”

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资源与产业 2024年第3期26卷 90-96页

作者：吴裕根司芗许书平王建忠自然资源部油气资源战略研究中心北京100045

本文运用统计分析方法,通过梳理全球及我国锂金属资源分布和锂矿资源的开发利用情况,以及新能源产业带动锂金属资源需求增长的情况,研究了我国在锂矿资源勘探、开发、利用中所存在的问题,并对我国锂矿资源的市场热度进行了理性分析。研... 详细信息

本文运用统计分析方法,通过梳理全球及我国锂金属资源分布和锂矿资源的开发利用情况,以及新能源产业带动锂金属资源需求增长的情况,研究了我国在锂矿资源勘探、开发、利用中所存在的问题,并对我国锂矿资源的市场热度进行了理性分析。研究结果表明:1)当今,我国的锂电产业发展迅速,使得对锂矿资源的需求一直居高不下,但是国内的锂矿产量还不能满足产业发展要求,因而必须从国外大量进口锂矿产品。2021年我国通过不断加大对锂矿资源的开发力度,使得国内对锂矿资源的对外依存度已经从最高峰时的80%多下降至了65%,2022年下降至了55%,但是对外依存度依旧偏高。2)近10年以来,我国锂矿资源的勘探工作无论在理论研究还是在找矿实践方面均取得较大进展,但是与国外矿业强国相比,我国在找矿突破和新增锂矿资源储量方面仍然与这些国家存在着较大差距。3)我国的锂矿资源开采量随着碳酸锂产品需求及价格的上涨有所增加,但仍然存在开采成本较高、技术有待进一步突破等问题。我国的锂辉石矿床品位高,但是规模小,且受地理环境限制,开采难度较大、开采利用率较低;我国的锂云母矿床虽然规模大、采矿难度小,但是矿床品位低、选矿难度较大;我国的盐湖卤水型锂矿资源虽然储量丰富,但受地理位置及高镁锂比提锂技术的影响,使得该锂矿产量一直提升缓慢。4)当前,我国各种社会资本纷纷投入了对国内锂矿探矿权的竞争,导致锂矿探矿权竞争溢价过高,参与竞争的企业常常要以千倍的溢价价格才能够获得锂矿探矿权。本研究认为取得锂矿探矿权不应是企业的最终目的,相关企业更应该通过加大对锂矿资源的勘探投入及加快勘探进度,并在后续的锂矿开采、碳酸锂生产中根据市场需求及时调整锂金属资源的生产与供给,以促进我国锂资源产业链、供应链的有序发展,才是企业取得锂矿探矿权的真正意义所在。

关键词：新能源锂矿资源保障供需形势开发利用理性思考

Hydrothermal Synthesis of SnO_2 Nanoparticles

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稀有金属材料与工程 2006年第A3期35卷 583-585页

作者： shuping Gong Cong xu Huan Liu Department of Electronic Science and Technology Huazhong University of Science and Technology Wuhan 430074 China

SnO_2 nanoparticles with the average size of 3.7 nm have been successfully synthesized by hydrothermal method. The particles were characterized by XRD,SEM and *** XRD results show that the products are all at nanometer scale, and the crystallite size increases with increasing of the heat-treatment *** SEM and TEM photographs indicate that the particles are all monodispersed with narrow size distribution.

关键词： hydrothermal tin oxide nanoparticle gas sensors