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Efficient gaseous iodine capture enhanced by charge-induced effect of covalent organic frameworks with dense tertiary-amine nodes

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Chinese Chemical Letters 2022年第7期33卷 3556-3560页

作者： Bo Jiang Yue Qi xiaofeng li Xinghua Guo Zhimin Jia Jie Zhang Yang li lijian Ma College of Chemistry Sichuan UniversityChengdu 610064China

Based on the outstanding application advantages of nitrogen-rich materials with regular porous frameworks in the capture of gaseous radioactive iodine,a series of covalent organic frameworks(COFs)with dual channels and abundant tertiary-amine active sites were constructed herein via a unique multinitrogen node *** high density of up-to-six nitrogen adsorption sites in a single structural unit of the products effectively improved the adsorption capacities of the materials for ***,the adsorption affinity of the active sites can be further regulated by charge-induced effect of different electrondonating groups introduced into the *** experiments combined with DFT theoretical calculations confirmed that the introduction of electron-donating groups can effectively increase the electron density around the active sites and enhance the binding energy between the materials and iodine,and thus improve the iodine adsorption capacity to 5.54 g/*** construction strategy of multi-nitrogen node and charge-induced effect proposed in this study provides an important guidance for the study of the structure-activity relationship of functional materials and the design and preparation of high-performance iodine adsorption materials.

关键词： Covalent organic frameworks Tertiary-amine nodes Charge-induced effect Gaseous iodine capture DFT theoretical calculation

Polarization Beats in a Cascade Three-Level System

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Chinese Physics Letters 1995年第11期12卷 669-672页

作者： MI Xin YU Zuhe JIANG Qian ZHANG Yanpeng li xiaofeng FU Panming Institute of Physics Academia SinicaBeijing 100080

Based on the interference between one-photon and two-photon processes,we report polarization beats in a cascade three-level system(PBCTS).We performed PBCTS experiments in Na vapor,which showed a modulation of the four-wave mixing signal intensity with period 55fs,corresponding to the beating between the resonant frequencies of the transitions from 3S_(1/2) to 3P_(3/2) and from 3P_(3/2) to 4D_(3/2,5/2).

关键词： Polarization resonant mixing

Design of a nanozyme-based magnetic nanoplatform to enhance photodynamic therapy and immunotherapy

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Journal of Pharmaceutical Analysis 2024年第9期14卷 1320-1329页

作者： Chen Bai Jiajing liu Luyao Bai Dapeng Yao xiaofeng li Haoran Zhang Dong Guo Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy Xuzhou Medical UniversityXuzhouJiangsu221004China Department of Radiology Xuzhou Cancer HospitalXuzhouJiangsu221004China

The tumor microenvironment, particularly the hypoxic property and glutathione (GSH) overexpression, substantially inhibits the efficacy of cancer therapy. In this article, we present the design of a magnetic nanoplatform (MNPT) comprised of a photosensitizer (Ce6) and an iron oxide (Fe3O4)/manganese oxide (MnO2) composite nanozyme. Reactive oxygen species (ROS), such as singlet oxygen (1O2) radicals produced by light irradiation and hydroxyl radicals (·OH) produced by catalysis, are therapeutic species. These therapeutic substances stimulate cell apoptosis by increasing oxidative stress. This apoptosis then triggers the immunological response, which combines photodynamic therapy and T-cell-mediated immunotherapy to treat cancer. Furthermore, MNPT can be utilized as a contrast agent in magnetic resonance and fluorescence dual-modality imaging to give real-time tracking and feedback on treatment.

关键词： Nanozyme Photodynamic therapy Tumor microenvironment Immunotherapy Dual-mode tomography

Nucleation and growth of L1_(2)-Al_(3)RE particles in aluminum alloys:A first-principles study

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Journal of Rare Earths 2023年第7期41卷 1116-1126,I0005页

作者： Touwen Fan Zixiong Ruan Feng Zhong Chaoyang Xie xiaofeng li Dongchu Chen Pingying Tang Yuanzhi Wu College of Science Hunan Institute of TechnologyHengyang 421002China Research Institute of Automobile Parts Technology Hunan Institute of TechnologyHengyang 421002China School of Materials Science and Engineering North University of Chin1Taiyuan 030051China School of Material Science and Hydrogen Energy Engineering Foshan UniversityFoshan 528001China Key Laboratory of New Electric Functional Materials of Guangxi Colleges and Universities Nanning Normal UniversityNanning 530023China

The internal mechanisms of nucleation and growth of L1_(2)-AI_(3)RE(RE=Sc,Y,La-Lu) second phases in Al alloys were investigated by combining first-principles calculations with quasi-harmonic approximation(QHA).The calculated results show that the diffusion rate D_s and chemical potential AG_V increase with the increase of *** the increase of atomic number,the D_s and the strain energy ΔE_(CS)increase firstly from Sc to La,and then decreases,while the calculated interface energy γ_(α/β) and ΔG_V show opposite *** on above calculated results,the critical nucleation radius R*and coarsening rate K_(LSW) are obtained from the classical nucleation theory(CNT) and LSW model of the Ostwald ripening of particles,*** the increase of atomic number,the R*increases firstly,and then decreases for all planes at finite *** the K_(LSW) shows opposite variation to the R^(*).From this point of view,it is reasonably speculated that Y and later RE elements can replace the expensive Sc for heat-resistance Al *** solubility c_(∞) of particles is usually very small at low temperature,and there is obvious solubility only when the temperature reaches 600 *** surface energies E_(sur) of AI_(3)RE compounds and Al solid solution are respectively larger and smaller than that of pure Al,respectively,except for the surface(001) and(110) of Al_(3)*** all planes,with the increase of atomic number of RE,E_(sur) decreases firstly from Sc to La,and then increases linearly to *** results are helpful for designing high performance heat-resistance Al alloys.

关键词： First-principles calculations Diffusion rate Quasi-harmonic approximation Particle nucleation and growth Rare earths

Effective regulation of the interaction process among three optical solitons

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Chinese Physics B 2024年第10期33卷 190-197页

作者： Houhui Yi xiaofeng li Junling Zhang Xin Zhang Guoli Ma School of Intelligent Manufacturing Weifang University of Science and TechnologyWeifang 262700China School of Aviation and Aerospace Tianjin Sino-German University of Applied SciencesTianjin 300350China

The interaction between three optical solitons is a complex and valuable research direction,which is of practical application for promoting the development of optical communication and all-optical information processing *** this paper,we start from the study of the variable-coefficient coupled higher-order nonlinear Schodinger equation(VCHNLSE),and obtain an analytical three-soliton solution of this *** on the obtained solution,the interaction of the three optical solitons is explored when they are incident from different initial velocities and *** the higher-order dispersion and nonlinear functions are sinusoidal,hyperbolic secant,and hyperbolic tangent functions,the transmission properties of three optical solitons before and after interactions are ***,this paper achieves effective regulation of amplitude and velocity of optical solitons as well as of the local state of interaction process,and interaction-free transmission of the three optical solitons is obtained with a small *** relevant conclusions of the paper are of great significance in promoting the development of high-speed and large-capacity optical communication,optical signal processing,and optical computing.

关键词： optical solitons solitons interactions nonlinear Schr¨odinger equation higher-order dispersion and nonlinear effects

The Geology, Fluid Inclusions, and O-S Isotopes of the Mibei Gold Deposit, Hunan Province, Southern China

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 992-1006页

作者： XUE Wenhao liANG Yayun li xiaofeng li Mingyi XIE Wenbo PENG Xue XIA Rui HE Hongsheng XIAO Jincheng School of Civil and Resource Engineering University of Science and Technology BeijingBeijing 100083China Geophysical and Geochemical Survey Institute of Hunan Changsha 410116China New Geological Energy Exploration and Development Engineering Technology Research Center of Hunan Changsha 410116China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences(Beijing)Beijing 100083China Comprehensive Survey Command Center for Natural Resources China Geological SurveyBeijing 100055China

The Mibei gold deposit,located in the southwestern part of the Xuefengshan uplift zone,the middle section of the Jiangnan orogenic belt in southern China,has estimated gold resources of approximately seven *** deposit is primarily a quartz vein-type gold deposit,with ore bodies occurring mainly within Neoproterozoic *** main metallic minerals in the ore are pyrite,chalcopyrite,and *** this study,the petrography and microthermometry of ore-forming fluid inclusions,oxygen isotopes of gold-bearing quartz,and sulfur isotopes of goldbearing sulfides and arsenopyrite were *** types of fluid inclusions were identified:type Ⅰa three-phase inclusions comprising vapor and two phases of liquids(V_(CO_(2))+L_(CO_(2))+L_(H2O)),type Ⅰb two-phase liquids(L_(CO_(2))+L_(H2O)),typeⅡ two-phase vapor-rich inclusions(V/V+L> 50%),and type Ⅲ pure liquid *** Ⅰ inclusions were heated uniformly to the liquid phase,type Ⅱ inclusions were heated uniformly to the gas phase,and type Ⅲ inclusions were heated without *** general,the temperature range of homogenization to liquid phase of fluid inclusions in the Mibei gold deposit is 204-227℃.The salinity of the inclusion ranges from 4.6 to 12.2 wt% NaCl *** δ~(18)O_(SMOW) of gold-bearing quartz varies from 16.9‰ to 17.5‰.The δ~(18)O_(H2O) of gold-bearing quartz are varied from 6.5‰ to 7.5‰.The δ~(34)S values of gold-bearing pyrite range from 1.7‰ to 6.8‰.The δ~(34)S values of gold-bearing arsenopy rite range from 5.6%o to 5.9‰.Theδ~(34)S values of pyrite from wall rocks slate range from 6.4‰ to 11.6‰.This evidence implies that the ore-forming fluids of the Mibei gold deposit originated from magmatic-hydrothermal processes,mixing with minor S from the surrounding *** with the evolution of the Jiangnan orogenic belt,due to the magmatic and tectonic activities of the Xuefengshan uplift during the Caledonian period,the fault seal mechanism controlled the ore-forming p

关键词： ore-forming fluid ore genesis Mibei gold deposit Xuefengshan uplift zone Jiangnan orogenic belt

Effect of rare-earth element Sm on the corrosion behavior of Mg-6Al-1.2Y-0.9Nd alloy

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Rare Metals 2010年第6期29卷 557-560页

作者： li Quan’an,li xiaofeng,ZHANG Qing,and CHEN Jun School of Materials Science and Engineering,Henan University of Science and Technology,Luoyang 471003,China School of Materials Science and Engineering Henan University of Science and Technology Luoyang China

The effect of Sm（0 wt.%-2 wt.%） addition on the corrosion behavior of Mg-6Al-1.2Y-0.9Nd alloy in 3.5 wt.% NaCl solution has been studied by static corrosion tests,corrosion morphology observation,corrosion scale and microstructure *** results show that,with the increasing of Sm content,the corrosion rate of the alloy decreases at first,then increases and reaches the valley at 0.5 wt.% *** reason is that the proper content of Sm addition can refine the precipitates and make the component and microstructure uniform,and therefore,it remarkably improves the corrosion resistance of the alloy.

关键词： magnesium alloys samarium corrosion behavior microstructure

Predicting Surface Roughness and Moisture of Bare Soils Using Multi- band Spectral Reflectance Under Field Conditions

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Chinese Geographical Science 2018年第6期28卷 986-997页

作者： CHEN Si ZHAO Kai JIANG Tao li xiaofeng ZHENG Xingming WAN Xiangkun ZHAO Xiaowei Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130102 China University of Chinese Academy of Sciences Beijing 100049 China College of Geoexploration Science and Technology Jilin University Changchun 130026 China

Soil surface roughness, denoted by the root mean square height(RMSH), and soil moisture(SM) are critical factors that affect the accuracy of quantitative remote sensing research due to their combined influence on spectral reflectance(SR). In regards to this issue, three SM levels and four RMSH levels were artificially designed in this study; a total of 12 plots was used, each plot had a size of 3 m × 3 m. Eight spectral observations were conducted from 14 to 30 October 2017 to investigate the correlation between RMSH, SM, and SR. On this basis, 6 commonly used bands of optical satellite sensors were selected in this study, which are red(675 nm), green(555 nm), blue(485 nm), near infrared(845 nm), shortwave infrared 1(1600 nm), and shortwave infrared 2(2200 nm). A negative correlation was found between SR and RMSH, and between SR and SM. The bands with higher coefficient of determination R^2 values were selected for stepwise multiple nonlinear regression analysis. Four characterized bands(i.e., blue, green, near infrared, and shortwave infrared 2) were chosen as the independent variables to estimate SM with R^2 and root mean square error(RMSE) values equal to 0.62 and 2.6%, respectively. Similarly, the four bands(green, red, near infrared, and shortwave infrared 1) were used to estimate RMSH with R^2 and RMSE values equal to 0.48 and 0.69 cm, respectively. These results indicate that the method used is not only suitable for estimating SM but can also be extended to the prediction of RMSH. Finally, the evaluation approach presented in this paper highly restores the real situation of the natural farmland surface on the one hand, and obtains high precision values of SM and RMSH on the other. The method can be further applied to the prediction of farmland SM and RMSH based on satellite and unmanned aerial vehicle(UAV) optical imagery.

关键词： soil surface roughness soil moisture spectral reflectance field conditions stepwise multiple nonlinear regression

A preliminary study on the volcanic intrusive complex type beryllium metallogenic belt from the southeast coast of China

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Science China Earth Sciences 2022年第8期65卷 1586-1600页

作者： Can RAO Rucheng WANG Fuyuan WU Xudong CHE xiaofeng li Qi WANG Zhiqi ZHANG Runqiu WU Key Laboratory of Geoscience Big Data and Deep Resource of Zhejiang Province School of Earth SciencesZhejiang UniversityHangzhou310027China State Key Laboratory for Mineral Deposits Research School of Earth Sciences and EngineeringNanjing UniversityNanjing210023China State Key Laboratory of lithosphere Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China

Beryllium(Be)is one of the unsubstitutable key metals in strategic emerging industries and national defense industries,mainly originating from volcanogenic Be ***,volcanogenic Be deposits have become important research objects of key metal deposits,with a focus on their occurrence,metallogenic mechanism,and resource *** the southeast coast of China,the Late Mesozoic volcanic intrusive complex has a good Be metallogenic background,and strong Be mineralization occurs in some *** geological investigation and analyses of samples from Southeast Zhejiang as well as Northeast and Southeast Fujian indicate that Be mineralization in the southeast coast of China is closely related to the hydrothermal processes in the volcanic intrusive *** Southeast Zhejiang,Be ore in the Qingtian area mainly occurs in granite porphyry,with the Be content reaching 939 ppm,while strong Be mineralization from Zhangji rhyolite porphyry in the Pingyang area contains up to 11400 ppm *** Xiapu County,Northeastern Fujian,the Dawan Be deposit is characterized by constituents of helvite and *** Pinghe County,Southeastern Fujian,the Fulishi Be ore is a quartz vein beryl-type *** results suggest that the volcanic intrusive complex area in the southeast coast of China has a wide range of Be mineralization and better Be metallogenic potential,and it is expected to become an important Be metallogenic belt in ***,we should thoroughly investigate the Be resources of granite porphyry,rhyolite porphyry,quartz porphyry,and quartz vein in this volcanic rock area,which can provide a theoretical basis for the exploration and guiding prospecting of volcanic intrusive complex Be deposits.

关键词： Volcanogenic Be deposit Beryllium resources Be-bearing minerals Beryllium metallogenic belt Southeast coast of China