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Photoluminescence and cathodoluminescence properties of CaLaGa_3O_7:Eu^(3+) phosphors

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International Journal of Minerals,Metallurgy and Materials 2012年第3期19卷 271-277页

作者： wen-yu zhao Sheng-li An Bin Fan Song-bo Li Ya-tang Dai School of Metallurgical and Ecological Engineering University of Science and Technology Beijng Beijing 100083 China Inner Mongolia University of Science and Technology Baotou 014010 China School of Materials Science and Engineering Southwest University of Science and Technology Mianyang 621000 China

The CaLaGa3O7：Eu3＋ phosphor was prepared by a chemical co-precipitation method. Field emission scanning electron microscopy （FE-SEM）, laser particle size analysis, X-ray diffraction （XRD）, photoluminescence （PL）, and cathodoluminescence （CL） spectra were util- ized to characterize the synthesized phosphor. The results revealed that the phosphor was composed of microspheres with a slight agglomerate phenomenon and was spherically shaped. The average grain size was about 1.0 μm. Eu3＋ ions, as luminescent centers, substituted La3＋ ions into the single crystal lattice of CaLaGa307 with the sites of Cs. Although the CL spectrum was greatly different from the PL spectrum, it had the strongest red emission corresponding to the 5D0→7F2 transition of Eu3＋. Under the excitation of UV light （287 nm） and electron beams （1.0-7.0 kV）, the chromaticity coordinates of the phosphor were found to be in the nearly red and orange light regions, respec- tively.

关键词： luminescence phosphors coprecipitation rare earths

Enhanced thermoelectric and mechanical properties of Bi_(0.5)Sb_(1.5)Te_(3) alloy with dispersed yttrium oxide ceramic nanoparticles

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Rare Metals 2024年第4期43卷 1758-1768页

作者： Cun-Cheng Li Ming-Wei Zhang Ji-Wu Xin Lei Wei wen-yu zhao School of Materials Science and Engineering Shandong University of TechnologyZibo255000China School of Electrical and Electronic Engineering Nanyang Technological UniversitySingapore639798Singapore State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan430070China

Reducing thermal conductivity while avoiding adverse interfacial reactions during sintering is crucial for improving the thermoelectric performance of Bi_(2)Te_(3)based *** ceramic nanoparticles are good candidates for achieving this *** this study,we designed and prepared a series of p-type Bi_(0.5)Sb_(1.5)Te_(3)nanocomposites decorated with Y_(2)O_(3)ceramic nanoparticles via ball-milling dispersion and spark-plasma *** to the chemical stability of the ceramics,no traces of atomic doping or interfacial reactions were *** measurements revealed that the Y_(2)O_(3)nanoparticles distributed along the grain boundaries acted as energy-dependent carrier-filtering centers to improve the scattering parameter and Seebeck coefficient,contributing to the elevated power factor even with a decreased electrical ***,the incorporated Y_(2)O_(3)nanoparticles and various defect structures they induced effectively strengthened the phonon scattering and suppressed the lattice thermal ***,a peak figure of merit(ZT)of 1.23 at 313 K was achieved for 0.4%Y_(2)O_(3)/Bi_(0.5)Sb_(1.5)Te_(3),which is 13%higher than that of the *** addition,the Vickers hardness of the composite material was 35%higher than that of the *** study demonstrates the effectiveness of ceramic nanoparticles in synergistic ally improving the thermoelectric and mechanical properties,which may be further extended to other thermoelectric systems.

关键词： Bi_(0.5)Sb_(1.5)Te_3 alloy Y_(2)O_(3) ceramic nanoparticles Microstructures Thermoelectric performance Mechanical properties

Mechanisms and regulation of organic acid accumulation in plant vacuoles

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Horticulture Research 2021年第1期8卷 3107-3116页

作者： Xiao-yu Huang Chu-Kun Wang yu-wen zhao Cui-Hui Sun Da-Gang Hu National Key Laboratory of Crop Biology Shandong Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient ProductionCollege of Horticulture Science and EngineeringShandong Agricultural UniversityTai’anShandong 271018China

In fleshy fruits,organic acids are the main source of fruit acidity and play an important role in regulating osmotic pressure,pH homeostasis,stress resistance,and fruit *** transport of organic acids from the cytosol to the vacuole and their storage are complex processes.A large number of transporters carry organic acids from the cytosol to the vacuole with the assistance of various proton pumps and ***,much remains to be explored regarding the vacuolar transport mechanism of organic acids as well as the substances involved and their *** this review,recent advances in the vacuolar transport mechanism of organic acids in plants are summarized from the perspectives of transporters,channels,proton pumps,and upstream regulators to better understand the complex regulatory networks involved in fruit acid formation.

关键词： summarized transport upstream

Residual Phase Noise and Time Jitters of Single-Chip Digital Frequency Dividers

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Journal of Electronic Science and Technology 2015年第3期13卷 264-268页

作者： Lu-Lu Yan Sen Meng wen-yu zhao wen-Ge Guo Hai-Feng Jiang Shou-Gang Zhang the Key Laboratory of Time and Frequency Standards National Time Service Center (NTSC) Chinese Academy of Sciences the School of Science Xi’an Shiyou University the Key Laboratory of Time and Frequency Standards National Time Service Center Chinese Academy of Sciences

In this paper, we demonstrate the residual phase noise of a few microwave frequency dividers which usually limit the performance of frequency synthesizers. In order to compare these dividers under different operation frequencies, we calculate additional time jitters of these dividers by using the measured phase noise. The time jitters are various from -0.1 fs to 43 fs in a bandwidth from 1 Hz to 100 Hz in dependent of models and operation frequencies. The HMC series frequency dividers exhibit outstanding performance for high operation frequencies, and the time jitters can be sub-fs. The time jitters of SP8401, MC10EP139, and MC100LVEL34 are comparable or even below that of HMC series for low operation frequencies.

关键词： Frequency divider phase noise spectra analysis time jitter

Regulation of a vacuolar proton-pumping P-ATPase MdPH5 by MdMYB73 and its role in malate accumulation and vacuolar acidification

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aBIOTECH 2023年第4期4卷 303-314页

作者： Xiao-yu Huang Ying Xiang yu-wen zhao Chu-Kun Wang Jia-Hui Wang wen-Yan Wang Xiao-Long Liu Quan Sun Da-Gang Hu National Research Center for Apple Engineering and Technology Shandong Collaborative Innovation Center of Fruit and Vegetable Quality and Efficient ProductionCollege of Horticulture Science and EngineeringShandong Agricultural UniversityTai’an 271018ShandongChina

As the main organic acid in fruits,malate is produced in the cytoplasm and is then transported into the *** accumulates by vacuolar proton pumps,transporters,and channels,affecting the taste and flavor of *** the three types of proton pumps(V-ATPases,V-PPases,and P-ATPases),the P-ATPases play an important role in the transport of malate into *** this study,the transcriptome data,collected at different stages after blooming and during storage,were analyzed and the results demonstrated that the expression of MdPH5,a vacuolar proton-pumping P-ATPase,was associated with both pre-and post-harvest malate ***,MdPH5 is localized at the tonoplast and regulates malate accumulation and vacuolar *** addition,MdMYB73,an upstream MYB transcription factor of MdPH5,directly binds to its promoter,thereby transcriptionally activating its expression and enhancing its *** this way,MdMYB73 can also affect malate accumulation and vacuolar ***,this study clarifies how MdMYB73 and MdPH5 act to regulate vacuolar malate transport systems,thereby affecting malate accumulation and vacuolar pH.

关键词： Apple Malate accumulation P-ATPase MdPH5 MdMYB73

Microwave frequency transfer over a 112-km urban fiber link based on electronic phase compensation

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Chinese Physics B 2020年第6期29卷 207-211页

作者： wen-Xiang Xue wen-yu zhao Hong-Lei Quan Cui-Chen zhao Yan Xing Hai-Feng Jiang Shou-Gang Zhang National Time Service Center Chinese Academy of SciencesXi’an 710600China Key Laboratory of Time and Frequency Primary Standards Chinese Academy of SciencesXi’an 710600China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

We demonstrate the transmission of a microwave frequency signal at 10 GHz over a 112-km urban fiber link based on a novel simple-architecture electronic phase compensation *** key element of the system is the low noise frequency divider by 4 to differentiate the frequency of the forward signal from that of the backward one,thus suppressing the effect of Brillouin backscattering and parasitic reflection along the *** terms of overlapping Allan deviation,the frequency transfer instability of 4.2×10-15 at 1-s integration time and 1.6×10-18 at one-day integration time was *** addition,its sensitivity to the polarization mode dispersion in fiber is analyzed by comparing the results with and without laser polarization ***,with simplicity and robustness,the system can offer great potentials in constructing cascaded frequency transfer system and facilitate the building of fiber-based microwave transfer network.

关键词： microwave frequency transfer phase compensation polarization mode dispersion

Observed permafrost thawing and disappearance near the altitudinal limit of permafrost in the Qilian Mountains

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Advances in Climate Change Research 2022年第5期13卷 642-650页

作者： wen SUN Tingjun ZHANG Gary D.CLOW Yan-Hua SUN wen-yu zhao Ben-Ben LIANG Cheng-Yan FAN Xiao-Qing PENG Bin CAO Key Laboratory of Western China's Environmental Systems(Ministry of Education) College of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China Institute of Arctic and Alpine Research University of Colorado BoulderBoulder 80303USA National Tibetan Plateau Data Center Key Laboratory of Tibetan Environmental Changes and Land Surface ProcessesInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Permafrost degradation has been widely reported on the Tibetan Plateau(TP).However,directly observed evidence of permafrost thawing processes and degradation rates are very limited,although it is expected to be prevalent near the periphery of a permafrost ***,we report permafrost changes and disappearance in the Qilian Mountains(northeastern TP)based on three boreholes instrumented along a 100 m transect during 2014–*** results show that permafrost has significantly degraded in the study area:the mean downward thawing rate from the permafrost table was about 0.16 m per year while the mean upward thawing rate from the permafrost base was about 0.23 m per *** estimate the mean lateral degradation rate of permafrost in this area was∼4.14 m per *** dramatically,the 1.5 m thick permafrost layer at one of the boreholes thawed completely between April of 2018 and December of *** results indicate that changes in climatic condition may have played only a limited role in controlling the active layer thickness in the vicinity of the altitudinal limit of permafrost;moisture content and soil conditions play key roles in site-specific permafrost *** study provides new quantitative insights for understanding changes near the altitudinal limit of permafrost,and we suggest that land surface models or Earth system model studies of the lateral heat exchanges should be implemented in order to better represent permafrost thawing processes.

关键词： Permafrost Permafrost degradation Permafrost lateral thawing Qilian Mountains

Deciphering the impact of glucose signaling on fruit quality

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Fruit Research 2022年第1期2卷 25-30页

作者： Chu-Kun Wang yu-wen zhao Cui-Hui Sun Da-Gang Hu National Key Laboratory of Crop Biology Shandong Collaborative Innovation Center of Fruit&Vegetable Quality and Efficient ProductionCollege of Horticulture Science and EngineeringShandong Agricultural UniversityTai'anShandong 271018China

Glucose is a preferred source of carbon and energy for *** addition to metabolic functions,glucose is a well-known signaling molecule that regulates plant growth and development through multiple *** this review,the mechanisms by which glucose signaling regulates the accumulation of sugars and organic acids,as well as the ripening of fleshy fruit,are *** analysis of these complex molecular networks demonstrates the impact of glucose signal perception on fruit quality.

关键词： sugar addition impact

Discovery of New Iridoids as Farnesoid X Receptor Agonists from Morinda officinalis: Agonistic Potentials and Molecular Stimulation

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Chinese Journal of Chemistry 2021年第5期39卷 1288-1296页

作者： Zhi-Lin Luan Fei Qiao wen-yu zhao wen-Hua Ming Zhen-Long yu Jie Liu Sheng-yun Dai Shuang-Hui Jiang Chao-Jie Lian Cheng-Peng Sun Bao-Jing Zhang Jian Zheng Shuang-Cheng Ma Xiao-Chi Ma Dalian Key Laboratory of Metabolic Target Characterization and Traditional Chinese Medicine Intervention College of PharmacyCollege of Integrative MedicineDalian Medical UniversityDalianLiaoning 116044China National Institutes for Food and Drug Control Beijing 102629China

The investigation of Morinda officinalis led to the isolation of twelve compounds(1-12),including three new iridoid glycosides morindallns A-C(1-3)and nine known compounds(4-12).Their structural identifications were conducted using HRMS,1D and 2D NMR,and electronic circular dichroism(ECD)spectra as well as quantum chemical *** 6 displayed the most significantly agonistic activity against farnesoid X receptor(FXR)with an EC_(50) value of 7.18 μM,and its agonistic effect was verified through the investigation of FXR downstream target genes including small heterodimer partner 1(SHP1),bile salt export pump(BSEP),and organic solute transporter subunit alpha and beta(OSTα and OSTβ).The potential interaction of compound 6 with FXR was analyzed by molecular docking and molecular dynamics stimulation,revealing that amino acid residues Leu287;Thr288,and Ser332 played a crucial role in the activation of compound 6 towards *** findings suggested that compound 6 could be regarded as a potential candidate for the development of FXR agonists.

关键词： Morinda officinalis Iridoid Farnesoid X receptor Agonistic effect