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Ce^(3+) sensitized Tb^(3+) and Dy^(3+) photoluminescence in β-LaB_(5)O_(9) prepared by sol-gel method

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Journal of Rare Earths 2022年第8期40卷 1181-1186页

作者： Yuxuan Qi Ruirui Yang Yan Gao Pengfei Jiang Rihong Cong Tao Yang College of Chemistry and Chemical Engineering Chongqing UniversityChongqing 401331China

Rare earth(RE) pentaborates,both α-and β-polymorphs,are good candidates for photoluminescent hosts suitable for various RE activators,Ce^(3+) acts not only as an activator itself,but also as a sensitizer to other rare earth activators,like in the case of commercial green phosphor CeMgAl_(11)O_(19):Tb^(3+).In this work,two solid solutions of β-La_(0.9-x)Ce_(0.1)Tb_(x)B_(5)O_(9)(0≤x≤0.15) and β-La_(0.9-y)Ce_(0.1)Dy_(y)B_(5)O_(9)(0≤y≤0.07)were prepared by sol-gel method with high crystallinity,and the phase purity was confirmed with careful analyses on powder X-ray diffraction patterns.Energy transfers are expected due to the overlapping of Ce^(3+)emission with the Tb^(3+)/Dy^(3+)excitation.Indeed,the steady photoluminescence spectra indicate the decrease of the Ce^(3+)emission and the increase of the Tb^(3+)/Dy^(3+) emission,and the fluorescence decay curves exhibit the decrease of the average lifetime of Ce^(3+).The energy transfer efficiency is estimated to be 60% at χ=0.15 and 55% at y=0.07,respectively.The mechanism is likely through the dipole-dipole electric interactions for both cases.With this rationale,the Tb^(3+)and Dy^(3+)emissions are greatly enhanced,in particular,the white emission of Dy^(3+)in β-La_(0.85)Ce_(0.1)Dy_(0.05)B_(5)O_(9) is enhanced by 20 times.

关键词： Rare earths Pentaborates Sol-gel method Photoluminescence Energy transfer

Theory,technology and application of grouted bolting in soft rock roadways of deep coal mines

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1463-1479页

作者： Hongpu Kang Jianwei Yang Pengfei Jiang Fuqiang Gao Wenzhou Li Jiafeng Li Huiyuan Chen Coal Mining Research Institute China Coal Technology and Engineering Group Co.Ltd.Beijing 100013China Coal Mining Branch China Coal Research InstituteBeijing 100013China State Key Laboratory of Intelligent Mining and Strata Control Beijing 100013China

The grouted bolt,combining rock bolting with grouting techniques,provides an effective solution for controlling the surrounding rock in deep soft rock and fractured roadways.It has been extensively applied in numerous deep mining areas characterized by soft rock roadways,where it has demonstrated remarkable control results.This article systematically explores the evolution of grouted bolting,covering its theoretical foundations,design methods,materials,construction processes,monitoring measures,and methods for assessing its effectiveness.The overview encompassed several key elements,delving into anchoring theory and grouting reinforcement theory.The new principle of high pretensioned high-pressure splitting grouted bolting collaborative active control is introduced.A fresh method for dynamic information design is also highlighted.The discussion touches on both conventional grouting rock bolts and cable bolts,as well as innovative grouted rock bolts and cables characterized by their high pretension,strength,and sealing hole pressure.An examination of the merits and demerits of standard inorganic and organic grouting materials versus the new inorganic–organic composite materials,including their specific application conditions,was conducted.Additionally,the article presents various methods and instruments to assess the support effect of grouting rock bolts,cable bolts,and grouting reinforcement.Furthermore,it provides a foundation for understanding the factors influencing decisions on grouted bolting timing,the sequence of grouting,the pressure applied,the volume of grout used,and the strategic arrangement of grouted rock bolts and cable bolts.The application of the high pretensioned high-pressure splitting grouted bolting collaborative control technology in a typical kilometer-deep soft rock mine in China—the soft coal seam and soft rock roadway in the Kouzidong coal mine,Huainan coal mining area,was introduced.Finally,the existing problems in grouted bolting control technology for deep soft rock roadways are analy

关键词： deep coal mine soft rock roadway grouted bolting rock bolt and cable grouting material high-pressure splitting grouting collaborative control technology

Synthesis of two A-B-C type conjugated amphiphilic triblock fullerene derivatives and their application in organic solar cells

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Chinese Chemical Letters 2020年第1期31卷 119-124页

作者： Jikang Liu Pengfei Jiang Yao Wang Guoli Tu Wuhan National Laboratory for Optoelectronics Huazhong University of Science and Technology

Two A-B-C type conjugated amphiphilic triblock fullerene derivatives C60-2 HMTPB and C60-2 EHTPB were obtained in multi steps synthesis with three different blocks,and the amphiphilic diblock molecular C60-4 TPB was also preferred as a reference.When as modifying layer on zinc oxide(ZnO),the three fullerene derivatives can all reduce the work function of ZnO via modulation of the interfacial dipoles and lead a better electrical coupling.As introducing treatment of toluene,the obvious self-assembly of fullerene derivatives were observed,which were supported by X-ray diffraction and contact angle of water measurement.Base on PTB7-Th:PC71 BM system,the inverted organic solar cells devices with structure of ITO/ZnO/fullerene derivatives/PTB7-Th:PC71BM/Mo03/Al got power conversion efficiencies of 8.62%,8.83%and 9.00%for C60-4 TPB,C60-2 HMTPB and C60-2 EHTPB,respectively,compared 8.13%of devices with bare ZnO.The result of conjugated amphiphilic triblock fullerene derivatives provides a straightforward approaching by simultaneously modulating the morphology and interfacial work function of ZnO,which can also lead high performance in optoelectronic devices.

关键词： Amphiphilic triblock fullerene derivatives Interfacial dipoles Interface compatibility Self-assembly Water contact angle

Antarctic krill antioxidant peptides show inferior IgE-binding ability and RBL-2H3 cell degranulation

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Food Science and Human Wellness 2023年第5期12卷 1772-1778页

作者： Jie Ding Chunyan Zhu Pengfei Jiang Libo Qi Na Sun Songyi Lin National Engineering Research Center of Seafood School of Food Science and TechnologyDalian Polytechnic UniversityDalian 116034China Collaborative Innovation Center of Seafood Deep Processing Dalian Polytechnic UniversityDalian 116034China Ganzhou Quanbiao Biological Technology Co. Ltd.Ganzhou 341100China

Enzymatic hydrolysis,isolation,and purification might make a great deal of difference in antioxidant activity and antigenicity of peptide components.This study aimed to isolate and purify antioxidant peptide components from Antarctic krill and evaluate their allergenicity of them.Electron paramagnetic resonance(EPR)spectroscopy results indicated 3-10 kDa Antarctic krill hydrolysates(AKHs)had higher DPPH and·OH radical scavenging rates.And the second component(N2-2)purified 3-10 kDa hydrolysate showed better ability to scavenge DPPH and·OH radicals(P<0.05),which were(47.43±2.18)%and(34.33±1.25)%,respectively.Additionally,indirect-ELISA results revealed that N2-1 had a weaker ability to bind specific IgE and that N2-2 had a lower binding capability to specific IgG1(P<0.05).And N2-2 had a higher EC50 value of(5.29±0.95)ng/mL(P<0.05)in cell degranulation assay,which was about 13.80 times that of Antarctic krill.Therefore,N2-2 might be the potential source of the antioxidant peptides with lower allergenicity.

关键词： Enzymatic hydrolysis Isolation Purification Antarctic krill antioxidant peptide Allergenicity

Oblique detonation wave triggered by a double wedge in hypersonic flow

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Chinese Journal of Aeronautics 2022年第4期35卷 176-184页

作者： Honghui TENG Yuhang ZHANG pengfei YANG Zonglin jiang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China State Key Laboratory of High Temperature Gas Dynamics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

Pressure-gain combustion has gained attention for airbreathing ramjet engine applications owing to its better thermodynamic efficiency and fuel consumption rate. In contrast with traditional detonation induced by a single wedge, the present study considers oblique shock interactions attached to double wedges in a hypersonic combustible flow. The temperature/pressure increases sharply across the interaction zone that initiates an exothermic reaction, finally resulting in an Oblique Detonation Wave(ODW). Compared with the case for a single-wedge ODW, the double-wedge geometry has great potential to control the initiation of the ODW. As a tentative study, two-dimensional compressible Euler equations with a two-step induction-reaction kinetic model are used to solve the detonation dynamics triggered by a double wedge. The effects of the wedge angles and wedge corner locations on the initiation structures are investigated numerically.The results show an ODW complex comprising three Oblique Shock Waves(OSWs), an induction zone, a curved detonation front, and an unburned/low-temperature gas belt close to the surface of the second wedge. Both the increasing wedge angle and downstream wedge corner location lead to an abrupt OSW–ODW transition type, whereas the former corresponds to the shock–shock interaction and the later has a greater effect on the exothermic chemical process. Analysis of the shock polar and flow scale confirms that the OSW–ODW initiation structure mainly depends on the coupling of shocks and heat release in a confined initiation zone.

关键词： Double wedge Hypersonic flow Initiation structures Oblique detonation Shock interactions

The behavior of a lithospheric magnetization and magnetic field model

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Earth and Planetary Physics 2023年第1期7卷 66-73页

作者： pengfei Liu Yi jiang Qing Yan Ann MHirt State Key Laboratory of Lunar and Planetary Sciences Macao University of Science and TechnologyMacaoChina CNSA Macao Center for Space Exploration and Science MacaoChina Institute of Geophysics ETH ZürichSonneggstrasse 5CH-8095 ZürichSwitzerland

The Earth’s“lithosphere”is its outer shell,made up of the Earth’s crust and outermost mantle.The part of the Earth’s magnetic field that originates in the lithosphere consists of a superposition of magnetic anomalies with a broad spectrum of sizes and intensities,which arise from geological and tectonic features.The lithospheric magnetic field is known from surface observations,and on larger scales from above-surface measurements.The increase in recent decades of satellites dedicated to measuring the Earth’s magnetic field has improved significantly our models of the Earth’s magnetic environment.Based on these increasing observations,a number of comprehensive field models have been constructed,some of which focus solely on the lithosphere,such as the MF model series.We present a map of lithospheric magnetic anomalies at 400 km altitude,based on a vertically integrated magnetization model.This height was chosen because it is the expected orbital altitude of the Macao Science Satellite-1(MSS-1)mission.The model presented herein indicates that the amplitude of the lithospheric anomalies at 400 km altitude is between-14.8 n T and 18.2 n T.This information is useful because it provides a reference for the lithospheric source of the Earth’s magnetic field that contributes to the magnetic measurements made from satellite instruments.The low inclination orbit of the MSS-1 mission will provide information that is sensitive to lateral variation within the lithosphere;these variations arise from plate tectonic features with longitudinal extent.In conclusion,the new MSS-1mission will provide valuable information in detecting compositional variations in the lithosphere,and in delineating large-scale geological structures.

关键词： vertically integrated magnetization lithospheric magnetic field field model MSS-1

Molybdenum tailored Co^(0)/Co^(2+)active pairs on a perovskite-type oxide for direct ethanol synthesis from syngas

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中国化学工程学报:英文版 2023年第7期59卷 279-289页

作者： Yi Wu pengfei Song Ningyan Li Yanan jiang Yuan Liu Tianjin Key Laboratory of Applied Catalysis Science and Technology School of Chemical EngineeringTianjin UniversityTianjin 300350China

Selective synthesis of ethanol from syngas under the Co-based catalysts is still challenging due to the hard of regulating the active site Co^(0) and Co^(2+)ratio.In this work,a series of CaTi_(0.9-x)Co_(x)Mo_(0.1)O_(3)(x=0,0.1-0.4)and CaTi_(0.7)Co_(0.3)O_(3) catalysts were prepared by using citric acid complexation method to promote the synthesis of ethanol.It was found that Mo species in the perovskite lattice can regulate the Co^(0) and Co^(2+)ratio through the domain-limiting effect of perovskite and the degree of Co reduction could be adjusted by changing the Co/Mo molar ratio.Among these investigated catalysts,the total selectivity of alcohols over the catalyst with the optimal Co/Mo ratio CaTi_(0.6)Co_(0.3)Mo_(0.1)O_(3) reached 39.1%,with ethanol accounting for 74.7%,which was ascribed to the moderate and tightly bound ratio of dissociative to non-dissociative adsorption sites on the surface and the balance of CH_(x)-CH_(y) coupling and C^(O) insertion.

关键词： Direct ethanol synthesis Cobalt Molybdenum Syngas Perovskite-type oxides

Fabrication of a superamphiphobic coating by a simple and flexible method

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Particuology 2018年第4期16卷 33-39页

作者： Pengfei Jiang Yanli Li Chuan Zhang Xuan Zhou Yongjiang School of Chemistry and Chemical Engineering. Southeast University Nanjing 211189 China Chengxian College Southeast University Nanjing 210088 China

A facile and flexible method to prepare raspberry-like nanoparticles that can be used as a superamphipho- bic coating is reported. Anatase TiO2 nanoparticles were chosen as the core because of their irregular morphology and photocatalytic performance. Anatase TiO2 nanoparticles were surrounded tightly by tiny functional fluoride-silica nanoparticles via the hydrolysis-condensation reaction of tetraethoxysi- lane and IH, 1H, 2H, 2H-perfluorodecyl triethoxysilane. The obtained Si-F@TiO2 nanoparticles can be sprayed or dipped directly onto various substrates. The coated film exhibited quite good liquid resistance, even when subjected to water jetting and sand abrasion. The photocatalytic effect of the coated anatase TiO2 with respect to formaldehyde was also studied and discussed. This method will provide more opportunities and fast access to practical applications in surface, environmental, and energy engineering.

关键词： Superamphiphobic coating TiO2 nanoparticle Fluoride-silica nanoparticle Photocatalytic effect Formaldehyde

Study on the estimation of Euler angles for Macau Science Satellite-1

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Earth and Planetary Physics 2023年第1期7卷 144-150页

作者： Qing Yan JiaMing Ou Le Suo Yi jiang pengfei Liu State Key Laboratory of Lunar and Planetary Sciences Macau University of Science and Technology Institute of Remote Sensing Satellite China Academy of Space Technology

The Euler angle estimation is a calibration method for vector data measured by the magnetometer on a satellite. It is used to find the relative rotation between the coordinate system of the magnetometer and the satellite(usually determined by Star Imagers).Before launch of the low-orbit, low-inclination Macau Science Satellite-1(known as MSS-1), we simulated the estimation of Euler angles by using the magnetic measurements of the in-orbit Swarm and China Seismo-Electromagnetic Satellite(noted as CSES), with various data combinations. In this study, 11 data sets were designed to analyze the estimation results for the MSS-1 orbit by using a joint estimation method of the geomagnetic field model parameters and Euler angles. For the model results, we found that all the spatial power spectral lines showed behavior consistent with that of the CHAOS-7.8 model at low degrees(corresponding to large-scale magnetic signals). The spectra of models without global data coverage deviated much more(by a maximum of ～104 nT2) from those of the CHAOS-7.8 model at higher degrees. For models with global data coverage and with various data combinations, the spectral lines were distributed similarly. Moreover, the models with accordant power spectral distributions demonstrated different Euler angle estimations. As more vector data at higher latitudes were included, the estimated Euler angles varied monotonically in all three directions.The models with vector data in the same latitude range showed similar Euler angle results, regardless of whether the poleward scalar data were included. The largest value difference was found between the models using vector data within ±40° latitudes and those using vector data within ±60° latitudes, which reached to ～28″. Therefore, we concluded that the inversion of the spherical harmonic Gauss coefficients in our tests was mainly affected by the spatial coverage range of the data, whereas the estimation of Euler angles largely depended on the latitude range where the vector data could be obtained. The

关键词： Macau Science Satellite-1 (MSS-1) geomagnetic fields Euler angle estimation low-inclination orbit