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Synthesis and Analysis of Tm^(3+) Doped YF_3 Upconversion Luminescent Nano-materials

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Chinese Journal of Structural Chemistry 2010年第7期29卷 993-1000页

作者： HUANG qing-ming Instrumentation Analysis and Research Center College of MaterialsScience and Engineering Fuzhou University Fuzhou Fujian 350002 China

Upconversion （UC） phosphor Tm3＋ doped YF3 nano-erystals were prepared by hydrothermal method under different conditions and characterized by Field Transmission electron microscopy （TEM）, Scanning electron microscopy （SEM） and X-ray diffraction （XRD）. Their UC luminescence properties were studied by fluorescence spectrophotometer with 980 nm diode laser excitation, and impact of different grain sizes and morphology on the UC luminescence intensity was discussed. The fluorescence decay lifetime was calculated by Multi-exponential function fitting method. Results show that UC emission intensity was enhanced with the reduction of grain size, and the decay lifetime is 0.60 us.

关键词： upconversion crystal morphology decay time Rietveld refinement

Improved hemimorphite flotation using xanthate as a collector with S(Ⅱ) and Pb(Ⅱ) activation

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International Journal of Minerals,Metallurgy and Materials 2018年第8期25卷 849-860页

作者： Kai Jia Qi-ming Feng Guo-fan Zhang qing Shi Yuan-jia luo Chang-bin Li School of Mineral Processing and Bioengineering Central South UniversityChangsha 410083China

The flotation of hemimorphite using the S(Ⅱ)–Pb(Ⅱ)–xanthate process,which includes sulfidization with sodium sulfide,activation by lead cations,and subsequent flotation with xanthate,was *** flotation results indicated that hemimorphite floats when the S(Ⅱ)–Pb(Ⅱ)–xanthate process is used; a maximum recovery of approximately 90% was ***-potential,contact-angle,scanning electron microscopy–energy-dispersive spectrometry(SEM–EDS),and diffuse-reflectance infrared Fourier transform spectroscopy(DRIFTS) measurements were used to characterize the activation products on the hemimorphite surface and their subsequent interaction with sodium butyl xanthate(SBX).The results showed that a Zn S coating formed on the hemimorphite surface after the sample was conditioned in an Na2 S ***,the formation of a Zn S coating on the hemimorphite surface did not improve hemimorphite *** the subsequent addition of lead cations,Pb S species formed on the mineral *** formation of the Pb S species on the surface of hemimorphite significantly increased the adsorption capacity of SBX,forming lead xanthate(referred to as chemical adsorption) and leading to a substantial improvement in hemimorphite *** results indicate that the addition of lead cations is a critical step in the successful flotation of hemimorphite using the sulfidization–lead ion activation–xanthate process.

关键词： hemimorphite sulfidization lead ion activation xanthate zeta potential DRIFTS

On disturbance rejection proportional-integral-differential control with model-free adaptation

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Control Theory and Technology 2023年第1期21卷 34-45页

作者： Zhuo-Yun Nie Gao-ming Li Lai-Cheng Yan qing-Guo Wang Ji-Liang luo School of Information Science and Engineering Huaqiao UniversityXiamen 100190FujianChina Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087GuangdongChina Guangdong Key Lab of AI and Multi-Modal Data Processing BNU-HKBU United International CollegeZhuhai 519087GuangdongChina

In this paper,an adaptive disturbance-rejection proportional–integral–differential(PID)control method is proposed for a class of nonlinear ***,PID-type criterion is introduced in a model-free adaptive control(MFAC)framework,which gives an optimal control interpretation for PID ***,the design of adaptive disturbance rejection PID is proposed based on this new interpretation to realize controller gain *** to the ingenious integration of active disturbance rejection and adaptive mechanism,the proposed adaptive disturbance rejection PID control scheme exhibits better control performance than MFAC ***,the boundedness of controller gain,the convergence of tracking error and the bounded-input–bounded-output stability are proved for the proposed control ***,the effectiveness of the proposed method is verified by numerical simulation.

关键词： Disturbance rejection PID Data-driven control-Error-driven model Model-free adaptive control

Possible Origin of a Newly Discovered GeV Gamma-Ray Source Fermi J1242.5+3236

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Research in Astronomy and Astrophysics 2023年第2期23卷 99-106页

作者： Xiu-Rong Mo ming-Hong luo Hong-Bin Tan qing-Wen Tang Ruo-Yu Liu Department of Physics School of Physics and Materials ScienceNanchang UniversityNanchang 330031China School of Astronomy and Space Science Nanjing UniversityNanjing 210023China

Based on the first 13.4 yr of Fermi science data in the energy range from 300 Me V to 500 Ge V,we discovered a bright Ge V gamma-ray source with a ~5.64σ detection,named Fermi J1242.5+3236,which has an offset of about0°.0996 from a nearby star-forming galaxy NGC *** using the 12 yr’ data,the detection significance of Fermi J1242.5+3236 is about 4.72σ.Fermi J1242.5+3236 is a steady point source without significant temporal variability and has a hard gamma-ray photon index of about-1.60 ± *** spatial offset and the hard gammaray spectrum disfavor this source as the diffuse gamma-ray emission from this *** new source might have a possible origin of an unidentified background blazar,which is more likely a high-synchrotron-peaked blazar for its hard gamma-ray photon index.A follow-up optical observation would help distinguish origin of Fermi J1242.5+3236.

关键词： galaxies starburst-galaxies star formation-gamma-rays galaxies-galaxies active

Highly uniform and nonlinear selection device based on trapezoidal band structure for high density nano- crossbar memory array

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Nano Research 2017年第10期10卷 3295-3302页

作者： qing luo Xiaoxin Xu Hangbing Lv Tiancheng Gong Shibing Long Qi Liu Ling Li ming Liu Key Laboratory of Microelectronics Devices & Integrated Technology Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM) Nanjing 211800 China

Crossbar array provides a cost-effective approach for achieving high-density integration of two-terminal functional devices. However, the ＂sneaking current problem＂, which can lead to read failure, is a severe challenge in crossbar arrays. To inhibit the sneaking current from unselected cells, the integration of individual selection devices is necessary. In this work, we report a novel TaOx-based selector exhibiting a trapezoidal band structure formed by tuning the concentration of defects in the oxide. Salient features such as a high current density （1 MA·cm^-2）, high selectivity （5 × 10^4）, low off-state current （-10 pA）, robust endurance （〉10^10）, self-compliance, and excellent uniformity were successfully achieved. The integrated one-selector one-resistor （1S1R） device exhibits high nonlinearity in the low resistance state （LRS）, which is quite effective in solving the sneaking current issue.

关键词： crossbar array selector trapezoidal barrier gradient oxygenconcentration high uniformity

Two new saponins from the aerial part of Astragalus membranaceus var. mongholicus

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Chinese Chemical Letters 2007年第5期18卷 554-556页

作者： qing Tao Yu Ping Li Zhi ming Bi Jun luo Xiao Dan Gao Key Laboratory of Modern Chinese Medicines Ministry of Education Nanjing 210038 China Department of Pharmacognosy China Pharmaceutical University Nanjing 210038 China

Two new saponins named mongholicoside A （1） and mongholicoside B （2） were isolated from the aerial part of Astragalus membranaceus var mongholicus. Their structures were determined by 1D and 2D NMR, ESI-MS techniq... 详细信息

关键词： Astragalus membranaceus vat. mongholicus Aerial part Triterpene saponin Mongholicoside A and B

Study on the quality of recombinant proteins using matrix-assisted laser desorption ionization time of flight mass spectrometry

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World Journal of Gastroenterology 1999年第3期5卷 235-240页

作者： ZHOU Guo-Hua luo Guo-An SUN Guo-qing CAO Ya-Cheng and ZHU ming-Sheng 清华大学北京 100084 中科院南京土壤所江苏南京华东医学生物技术所江苏南京

AIM To study the possibility of matrix-assistedlaser desorption/ionization time of flight massspectrometry (MALDI--TOF MS) for controllingthe quality of recombinant *** By using MALDI--TOF MS, themoleCular weights and purity of recombinantbioactive proteins were *** The molecular weights and puritywere obtained in nine recombinant bioactiveproteins, including interleukin 2, tumor necrosisfactor Q, granulocyte--macrophage colonystimulating factor, interferon aZb, interferon al,erythropoietin, calmodulin and its fragment, andneuronal nitric oxide synthase were ***--TOF MS was also used to assay specificproteins in the mixtures and to characterize theerythropoietin tryptic *** The results showed that MALDITOF MS can be employed for the effective qualitycontrol of recombinant proteins.

关键词： MALDI time

The nucleocapsid of vesicular stomatitis virus

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Science China(Life Sciences) 2012年第4期55卷 291-300页

作者： luo ming Department of Microbiology the University of Alabama at Birmingham Birmingham 35294 USA

The nucleocapsid of vesicular stomatitis virus serves as the genomic template for transcription and replication. The viral genomic RNA is sequestered in the nucleocapsid in every step of the virus replication cycle. The structure of the nucleocapsid and the entire virion revealed how the viral genomic RNA is encapsidated and packaged in the virus. A unique mechanism for viral RNA synthesis is derived from the structure of the nuleocapsid and its interactions with the viral RNA-dependent RNA polymerase.

关键词： RNA cavity cross-molecular interactions RNA access phosphoprotein binding to the nucleocapsid bullet-shaped vi-rion

Ergodicity recovery of random walk in heterogeneous disordered media

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Chinese Physics B 2020年第5期29卷 165-173页

作者： Liang luo ming Yi Department of Physics Huazhong Agricultural UniversityWuhan 430070China Institute of Applied Physics Huazhong Agricultural UniversityWuhan 430070China School of Mathematics and Physics China University of GeosciencesWuhan 430074China

Significant and persistent trajectory-to-trajectory variance are commonly observed in particle tracking experiments,which have become a major challenge for the experimental data *** this theoretical paper we investigate the ergodicity recovery behavior,which helps clarify the origin and the convergence of trajectory-to-trajectory fluctuation in various heterogeneous disordered *** concepts of self-averaging and ergodicity are revisited in the context of trajectory *** slow ergodicity recovery and the non-Gaussian diffusion in the annealed disordered media are shown as the consequences of the central limit theorem in different *** strange ergodicity recovery behavior is reported in the quenched disordered case,which arises from a localization *** first-passage approach is introduced to the ergodicity analysis for this case,of which the central limit theorem can be employed and the ergodicity is recovered in the length scale of diffusivity correlation.

关键词： anomalous diffusion random walk disordered systems non-Gaussian diffusion