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Opto-Electronic Advances 2024年第9期7卷 54-63页

作者： zhi Wu Leimeng Xu Jindi Wang Jizhong song Key Laboratory of Materials Physics of Ministry of Education Laboratory of Zhongyuan LightSchool of PhysicsZhengzhou UniversityDaxue Road 75Zhengzhou 450052China

Ag-In-Ga-S(AIGS)quantum dots(QDs)have recently attracted great interests due to the outstanding optical properties and eco-friendly components,which are considered as an alternative replacement for toxic Pb-and Cd-based ***,enormous attention has been paid to how to narrow their broadband spectra,ignoring the application advantages of the broadband *** this work,the AIGS QDs with controllable broad green-red dual-emission are first reported,which is achieved through adjusting the size distribution of QDs by controlling the nucleation and growth of AIGS ***,the AIGS QDs exhibit broad dual-emission at green-and red-band evidenced by photoluminescence(PL)spectra,and the PL relative intensity and peak position can be finely ***,the dual-emission is the intrinsic characteristics from the difference in confinement effect of large particles and tiny particles confirmed by temperature-dependent PL ***,the AIGS QDs(the size consists of 17 nm and 3.7 nm)with 530 nm and 630 nm emission could successfully be synthesized at 2.0°*** combining the blue light-emitting diode(LED)chips and dual-emission AIGS QDs,the constructed white light-emitting devices(WLEDs)exhibit a continuous and broad spectrum like natural sunlight with the Commission Internationale de l’Eclairage(CIE)chromaticity coordinates of(0.33,0.31),a correlated color temperature(CCT)of 542. K,color rendering index(CRI)of 90,and luminous efficacy of radiation(LER)of 12. lm/W,which indicates that the AIGS QDs have huge potential for lighting applications.

关键词： quantum dots Ag-In-Ga-S dual emission white light-emitting diodes

Grain-boundary segregation and grain growth in nanocrystalline substitutional solid solution alloys

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Journal of Materials Science & Technology 2024年第1期168卷 239-249页

作者： Fawei Tang Chao Hou Hao Lu zhi Zhao Xiaoyan song Faculty of Materials and Manufacturing Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

A model for describing solute segregation at grain boundaries has been developed for substitutional solid solution alloys,which integrates multiple factors from atomic to microstructural scales.A concept of mo-lar Gibbs free energy of segregation was introduced to evaluate the segregating capability of the solute elements in a closed system,through which the influences of grain boundary structure,grain size,ma-terial composition,and external conditions were *** on the evaluation of various energy forms related to solute segregation and grain growth processes,the nature of the thermal stabilization of nanograin structures by solute segregation was disclosed.A criterion for the destabilization of nanostruc-tures,which is determined by the competition of the change rates between the molar Gibbs free energy of segregation and the total energy of grain boundaries with grain size,has been *** study provided guideline to achieve high-temperature stability of nanograin structures of solid solution alloys even for the weakly segregating nanocrystalline systems.

关键词： Substitutional solid solution Grain boundary segregation Thermal stabilization Solute concentration Grain size

Neutron irradiation influence on high-power thyristor device under fusion environment

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Nuclear Science and Techniques 2024年第4期35卷 65-81页

作者： Wei Tong Hua Li Meng Xu zhi-Quan song Bo Chen School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

Because of their economy and applicability,high-power thyristor devices are widely used in the power supply systems for large fusion *** high-dose neutrons produced by deuterium–tritium(D–T)fusion reactions are irradiated on a thyristor device for a long time,the electrical characteristics of the device change,which may eventually cause irreversible *** this study,with the thyristor switch of the commutation circuit in the quench protection system(QPS)of a fusion device as the study object,the relationship between the internal physical structure and external electrical parameters of the irradiated thyristor is ***,a series of targeted thyristor physical simulations and neutron irradiation experiments are conducted to verify the accuracy of the theoretical *** addition,the effect of irradiated thyristor electrical characteristic changes on the entire QPS is studied by accurate simulation,providing valuable guidelines for the maintenance and renovation of the QPS.

关键词： Fusion device Neutron irradiation effects Thyristor Quench protection

Interpretation and characterization of rate of penetration intelligent prediction model

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Petroleum Science 2024年第1期21卷 582-596页

作者： zhi-Jun Pei Xian-zhi {2. Hai-Tao Wang Yi-Qi Shi Shou-Ceng Tian Gen-Sheng Li College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102249China State Key Laboratory of Petroleum Resources and Prospecting Beijing102249China Kunlun Digital Technology Co. Ltd.Beijing102206China

Accurate prediction of the rate of penetration(ROP)is significant for drilling *** the intelligent ROP prediction model based on fully connected neural networks(FNN)outperforms traditional ROP equations and machine learning algorithms,its lack of interpretability undermines its *** study proposes a novel interpretation and characterization method for the FNN ROP prediction model using the Rectified Linear Unit(ReLU)activation *** leveraging the derivative of the ReLU function,the FNN function calculation process is transformed into vector *** FNN model is linearly characterized through further simplification,enabling its interpretation and *** proposed method is applied in ROP prediction scenarios using drilling data from three vertical wells in the Tarim *** results demonstrate that the FNN ROP prediction model with ReLU as the activation function performs exceptionally *** relative activation frequency curve of hidden layer neurons aids in analyzing the overfitting of the FNN ROP model and determining drilling data *** the well sections with similar drilling data,averaging the weight parameters enables linear characterization of the FNN ROP prediction model,leading to the establishment of a corresponding linear representation ***,the quantitative analysis of each feature's influence on ROP facilitates the proposal of drilling parameter optimization schemes for the current well *** established linear characterization equation exhibits high precision,strong stability,and adaptability through the application and validation across multiple well sections.

关键词： Fully connected neural network Explainable artificial intelligence Rate of penetration ReLU active function Deep learning Machine learning

Enantioselective Construction of Polycyclic Chromanes through Organocatalytic Sequential Quintuple Reaction via One-Pot Step-Wise Procedure

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Chinese Journal of Chemistry 2024年第18期42卷 2197-2202页

作者： Jie Wang Hang Qin Ya-Li song Fei Cao zhi-Hao You Key Laboratory of Pharmaceutical Quality Controlof Hebei Province College of Pharmaceutical SciencesHebei UniversityBaodingHebei 071002China Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education BaodingHebei 071002China

An efficient and highly stereoselective synthetic method to access polycyclic chromanes has been achieved through organocatalyzed one-pot step-wise reactions involving 2.hydroxycinnamaldehydes,2.aminochalcones,and malononitrile as *** reactions underwent a quintuple process by aza-Michael/Michael/Knoevenagel/oxa-Michael/aldol-type reaction in sequence to give products bearing 3 new generated rings and 5 chiral centers in moderate to quantitative yields with excellent stereoselectivities.

关键词： Asymmetric catalysis Organocatalysis Cyclization Quintuple reaction Polycycles Heterocycles Chromane One-pot reaction

Spectroscopic and temperature sensing properties of Sm3+ in self-activated CsLu（WO4）2.phosphors

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Journal of Rare Earths 2024年第11期42卷 2033-2042页

作者： Mingjun song Jing Wang zhi Xie Li Liu Wang Zhao Weiwei Zhou School of Chemistry Chemical and Environmental EngineeringWeifang University College of Mechanical and Electrical Engineering Fujian Agriculture and Forestry University School of Chemistry and Materials Engineering Huainan Normal University

In this research,a series of Sm3+doped CsLu（WO4）2.hosphors was prepared via high temperature solid phase technique to design new red phosphors and optical thermometric *** structures,morphology,band gap and luminescence properties were characterized by X-ray diffraction,scanning electron microscopy,diffuse reflection and luminescence spectra,*** UV excitation,CsLu（WO4）2.ives rise to a blue broad emission band between 350 and 700 nm,which stems from the3T1u→1A1gtransition of *** Sm3+is introduced into CsLu（WO4）2.energy transfer between WO66-groups and Sm3+ions takes place in CsLu（WO4）2.Sm3+phosphors,and color-tunable luminescence from blue to red is realized by controlling the Sm3+doping *** energy transfer efficiency between WO66-groups and Sm3+ons was analyzed,and the energy transfer mechanism was determined to be dipole-dipole *** to the temperature-dependent luminescence spectra,WO66-groups and Sm3+ions exhibit large discrepancy in thermal quenching rates,and thus the temperature sensing properties of CsLu（WO4）2.Sm3+in the temperature range of 2.3-403 K were *** on the framework of fluorescence intensity ratio theory,the basic optical thermometry parameters including absolute and relative sensitivity of CsLu（WO4）2.Sm3+we re calculated and the results show that it has great potential for application in optical thermometry.

关键词： Energy transfer Fluorescence intensity ratio Optical thermometry Phosphors Rare earths

Polydatin ameliorates hepatic ischemia-reperfusion injury by modulating macrophage polarization

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 25-34页

作者： Hai-Li Bao Chuan-zhi Chen Chang-Zhen Ren Ke-Yan Sun Hao Liu Shao-Hua song zhi-Ren Fu Department of Organ Transplantation Shanghai Changzheng HospitalNavy Military Medical UniversityShanghai 200003China Department of Surgical Oncology the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Department of Cardiology Shanghai Changzheng HospitalNaval Military Medical UniversityShanghai 200003China Department of General Surgery Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China

Background:Polydatin,a glucoside of resveratrol,has shown protective effects against various ***,little is known about its effect on hepatic ischemia-reperfusion(I/R)*** study aimed to elucidate whether polydatin protects liver against I/R-induced injury and to explore the underlying ***:After gavage feeding polydatin once daily for a week,mice underwent a partial hepatic I/R *** alanine aminotransferase(ALT)/aspartate aminotransferase(AST),hematoxylin-eosin(H&E)and TdT-mediated dUTP nick-end labeling(TUNEL)staining were used to evaluate liver *** severity related to the inflammatory response and reactive oxygen species(ROS)production was also ***,immunofluorescence and Western blotting were used to detect macrophage polarization and the NF-κB signaling pathway in ***:Compared with the I/R group,polydatin pretreatment significantly attenuated I/R-induced liver damage and *** oxidative stress marker(dihydroethidium fluorescence,malondialdehyde,superoxide dismutase and glutathione peroxidase)and I/R related inflammatory cytokines(interleukin1β,interleukin-10 and tumor necrosis factor-α)were significantly suppressed after polydatin *** addition,the result of immunofluorescence indicated that polydatin reduced the polarization of macrophages toward M1 macrophages both in vivo and in *** blotting showed that polydatin inhibited the pro-inflammatory function of RAW2.4.7 via down-regulating the NF-κB signaling ***:Polydatin protects the liver from I/R injury by remodeling macrophage polarization via NFκB signaling.

关键词： Hepatic ischemia-reperfusion injury Polydatin Macrophage Polarization Inflammation

Tetraphenylethylene dicycle helicates: circularly polarized luminescence and chiral recognition based on emission wavelength change

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Science China Chemistry 2024年第11期67卷 3817-3824页

作者： zhi-Rong Xu Miao-Li Gao Ming Hu Wei Yu Yan-song Zheng Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Chiral tetraphenylethylene(TPE) dicycle tetraaldehyde and TPE dicycle tetraacids bearing optically pure groups on the cycles were designed and synthesized. Due to the propeller-like conformation immobilization of TPE unit, this new class of TPE dicycle was resolved into M-and P-enantiomers, which could emit strong circular polarized luminescence(CPL). Interestingly,these TPE helicates displayed exceptional ability of molecule recognition. While the TPE dicycle tetraaldehyde could detect the microscale water in anhydrous tetrahydrofuran, the chiral TPE dicycle tetraacid could display different fluorescent color after interacting with two enantiomers of a wide variety of chiral amines including monoamines, diamines, and aminols, which could be applied to chiral recognition of these chiral amines. Furthermore, the emission wavelength of TPE dicycle tetraacid was found to change linearly with the enantiomer purity of chiral amine from enantiomer excess(ee) percent-100% to +100%, for the first time showing the potential for quantitative chiral analysis of chiral amines based on emission wavelength change. The emission wavelength was affected less by environmental factors than fluorescence intensity, which would enable the chiral analysis based on wavelength change with higher accuracy and repeatability.

关键词： TPE dicycle helicate CPL chiral recognition enantiomer excess analysis emission wavelength change

A seven-crystal spectrometer for high-energy resolution X-ray spectroscopy at Shanghai Synchrotron Radiation Facility

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Nuclear Science and Techniques 2024年第9期35卷 82-91页

作者： Bing-Bao Mei Liang-Xin Wang song-Qi Gu Xiao-zhi Su Shuo Zhang Yao Wei Jing-Yuan Ma Zheng Jiang Fei song Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201800China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201204China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

A Johann-type X-ray spectrometer was successfully developed at the hard X-ray branch(in-vacuum undulator with a 2.-mm periodic length)of the energy material beamline(E-line)at the Shanghai Synchrotron Radiation Facility(SSRF).This spectrometer was utilized to implement X-ray emission spectroscopy(XES),high-energy resolution fluorescence-detected X-ray absorption spectroscopy(HERFD-XAS),and resonant inelastic X-ray *** spherically bent crystals were positioned on the respective vertical 500-mm-diameter Rowland circles,adopting an area detector to increase the solid angle to 1.75%of 4πsr,facilitating the study of low-concentrate systems under complex reaction *** under the atmosphere pressure,the spectrometer covers the energy region from 3.5 to 18 keV,with the Bragg angle ranging from 73°to 86°during vertical *** offers a promised energy resolution of sub-eV(XES)and super-eV(HERFD-XAS).Generally,these comprehensive core-level spectroscopy methods based on hard X-rays at the E-line with an extremely high photon flux can meet the crucial requirements of a green energy ***,they provide substantial support for scientific advances in fundamental research.

关键词： X-ray emission spectroscopy High-energy-resolution X-ray spectrometer Johann geometry Energy materials SSRF

Quasi-in-situ Observation and SKPFM Studies on Phosphate Protective Film and Surface Micro-Galvanic Corrosion in Biological Mg-3Zn-xNd Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 648-664页

作者： Zhaochen Yu Kaixuan Feng Shuyun Deng Yang Chen Hong Yan Honggun song Chao Luo zhi Hu School of Advanced Manufacturing Nanchang UniversityNanchang330031China Institute for Advanced Study Nanchang UniversityNanchang330031China

The phosphate protective film and micro-galvanic corrosion of biological Mg-3Zn-xNd (x = 0, 0.6, 1.2. alloys were investigated by scanning and transmission electron microscopy, quasi-in-situ observation, scanning Kelvin probe force microscopy (SKPFM) and electrochemical tests. The results revealed the Mg-Zn-Nd phases formed in Mg-3Zn alloy contained with Nd. Adding Nd resulted in a significant decline in the cracks of the phosphate protective film and micro-galvanic corrosion of alloys, which were recorded by quasi-in-situ observation. In addition, the Volta potential difference of Mg-Zn-Nd/α-Mg (~ 188 mV) was lower than MgZn/α-Mg (~ 419 mV) and Zn-rich/α-Mg (~ 2.0 mV), and the corrosion rates of alloys markedly decreased after the addition of 0.6 wt% Nd. The improvement in corrosion resistance of Nd-containing alloys was mainly attributed to the following: (i) the addition of Nd reduced the Volta potential difference (second phases/α-Mg);(ii) the phosphate protective film containing Nd_(2.O_(3) deposited on the surface of the alloys, effectively preventing the penetration of harmful anions.

关键词： Magnesium alloys Quasi-in-situ observation Phosphate protective film Scanning Kelvin probe force microscopy(SKPFM) Micro-galvanic corrosion