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Zircon U/Pb dating and Hf-O isotopes of the Zhouan ultramafic intrusion in the northern margin of the Yangtze Block,SW China:Constraints on the nature of mantle source and timing of the supercontinent Rodinia breakup

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Science Bulletin 2013年第7期58卷 777-787页

作者： WANG MengXi WANG ChristinaYan zhao junhong Key Laboratory of Mineralogy and Metallogeny Guangzhou Institute of GeochemistryChinese Academy of Sciences Graduate University of Chinese Academy of Sciences Department of Earth Sciences China University of Geosciences

The Zhouan ultramafic intrusion in the northern margin of the Yangtze Block is mainly composed of *** grains selected from lherzolite are irregular in shape with distinct oscillatory and sector zoning and have Th/U ratios ranging from 0.8 to 10.6,indicating a magmatic *** weighted average 206 Pb/238 U age is 637±4 Ma (2σ,n=15),which can be considered as the crystallization age of the Zhouan *** grains have δ18O values ranging from 5.2‰ to 7.0‰,with an averaged value of 5.8±0.4‰ (1σ,n=33),similar to the mantle δ18O value of *** 176Hf/177Hf(t) ratios range from 0.282410 to 0.282594 with εHf(t) values ranging from 1.3 to 7.6,lower than the corresponding value of the depleted mantle (～15),indicating an enriched mantle *** enriched mantle source may have generated from a metasomatized lithospheric mantle with subducted slab.A number of ～635 Ma mafic-ultramafic intrusions in the Suizao basin are associated with coeval bimodal volcanics of the Yaolinghe Formation,indicating a continental rift *** ～635 Ma magmatic event in this region may represent the product of the last breakup of the Rodinia supercontinent in the northern margin of the Yangtze Block at Neoproterozoic.

关键词： zircon Hf-O isotopes Zhouan ultramafic intrusion northern margin of the Yangtze Block Neoproterozoic

Coherent video generation for multiple hand-held cameras with dynamic foreground

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Computational Visual Media 2020年第3期6卷 291-306页

作者： Fang-Lue Zhang Connelly Barnes Hao-Tian Zhang junhong zhao Gabriel Salas Victoria University of Wellington Wellington 6012New Zealand Adobe Research SeattleUSA Stanford University San FranciscoUSA

For many social events such as public performances, multiple hand-held cameras may capture the same event. This footage is often collected by amateur cinematographers who typically have little control over the scene and may not pay close attention to the camera. For these reasons, each individually captured video may fail to cover the whole time of the event, or may lose track of interesting foreground content such as a performer. We introduce a new algorithm that can synthesize a single smooth video sequence of moving foreground objects captured by multiple hand-held cameras. This allows later viewers to gain a cohesive narrative experience that can transition between different cameras, even though the input footage may be less than ideal. We first introduce a graph-based method for selecting a good transition route. This allows us to automatically select good cut points for the hand-held videos, so that smooth transitions can be created between the resulting video shots. We also propose a method to synthesize a smooth photorealistic transition video between each pair of hand-held cameras, which preserves dynamic foreground content during this transition. Our experiments demonstrate that our method outperforms previous state-of-the-art methods, which struggle to preserve dynamic foreground content.

关键词： dynamic preserve camera

Sm-Nd isotope dating of hydrothermal calcites from the Xikuangshan antimony deposit,Central Hunan

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Chinese Science Bulletin 2002年第13期47卷 1134-1137页

作者： PENG Jiantang HU Ruizhong LIN Yuanxian zhao junhong Institute of Geochemistry Chinese Academy of SciencesGuiyang 550002China Tianjin Institute of Geology&Mineral Resources Chinese Academy of Geological SciencesTianjin 300170China

The research on Samarium-Neodymium isotope systematics of hydrothermal calcites from the Xi-kuangshan antimony deposit, Central Hunan, places precise timing constraints on the Sb mineralization in this area. It is revealed that the Xikuangshan deposit formed during the late Jurassic-early Cretaceous Period, the early- and late-stage mineralization took place at (155.5±1.1) Ma and (124.1±3.7) Ma, respectively. The accurate age determination of mineralization is very crucial for revealing the super-enrichment mechanism of the element Sb at the Xikuangshan mine, and lays some foundations for the further understandings of its ore genesis and mineralization mechanism.

关键词： mineralization epoch Sm-Nd isotope systematics hydro-thermal calcites Xikuangshan antimony deposit.

Preparation and characterization of PVDF-PFSA flat sheet ultrafiltration membranes

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Frontiers of Chemical Science and Engineering 2012年第3期6卷 301-310页

作者： Jiquan MA junhong zhao Zhongbin REN Lei LI School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Sinopec International Petroleum Exploration and Production Corporation Sudan Branch Beijing 100029China

High performance polyvinylidene fluoride （PVDF） flat sheet ultrafiltration （UF） membranes have been prepared by an immersion precipitation phase inversion method using perfluorosulfonic acid （PFSA） as a pore former and as a hydrophilic component of the membranes and polyethylene glycol （Mw = 400）（PEG400） as a pore forming agent. The effects of the presence of PEG and the concentration of the PFSA on the phase separation of the casting solutions and on the morphologies and performance of UF membranes including their porosity, water flux, rejection of bovine serum albumin （BSA） protein, and anti-fouling property were investigated. Phase diagrams, viscosities and the phase separations upon exposure to water vapor showed that both PEG400 and PFSA promoted demixing of the casting solution. Scanning electron microscopy measurements showed that the PVDF-PFSA blend membranes had more macropores and finger-like structures than the native PVDF membranes. The PVDF-PFSA membrane （5 wt-% PEG400 ＋ 5 wt-% PFSA） had a pure water flux of 141.7L/m2.h, a BSA rejection of 90.1% and a relative pure water flux reduction （RFR） of 15.28%. These properties were greatly superior to those of the native PVDF membrane （pure water flux of 5.6 L/m2. h, BSA rejection of 96.3% and RFR of 42.86%）.

关键词： polyvinylidene fluoride perfluorosulfonic acid polyethylene glycol flat sheet membrane ultrafiltration

Petrogenesis of the Xihuashan Granite in Southern Jiangxi Province,South China:Constraints from Zircon U-Pb Geochronology,Geochemistry and Nd Isotopes

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Acta Geologica Sinica(English Edition) 2012年第1期86卷 131-152页

作者： YANG Jiehua PENG Jiantang zhao junhong FU Yazhou YANG Chen HONG Yinglong State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China Graduate University of Chinese Academy of Sciences Beijing 100049China School of Geosciences and Info-physics Engineering Center South UniversityChangsha 410083China State Key Laboratory of Geological Processes and Mineral Resources China University of GeoscieneesWuhan 430074China

Mesozoic granitic intrusions are widely distributed in the Nanling region, South China. Yanshanian granites are closely connected with the formation of tungsten deposits. The Xihuashan granite is a typical representative of tungsten-bearing granite. The Xihuashan granite consists mainly of medium-grained porphyritic biotite granite, medium-grained biotite granite and fine-grained twomica granite, which correspond to LA-ICP-MS zircon U-Pb ages of 555.5±0.4 Ma, 553.0±0.6 Ma and 552.8±0.9 Ma, respectively. Rocks from the Xihuashan mining area displays high SlOe （73.85% to 76.49%） and NaeO＋K20 contents （8.09% to 9.43%）, belonging to high-K calc-alkaline series. They are metaluminous to weakly peraluminous with A/CNK values ranging from 0.96 to 5.06. All granites in this study area are rich in Rb, Th, U and Pb, and depleted in Ba, Sr, P, Ti, Nb and Eu, especially depleted in medium-grained biotite granite and fine-grained two-mica granite. The medium-grained porphyritic biotite granites usually have high LREE concentrations, whereas medium-grained biotite granite and fine-grained two-mica granite displays high HREE contents. Our geochemical data reveal that the studied rocks are highly fractionated I-type granite. The magma underwent strong magma differentiation with decreasing temperature and increasing oxygen fugacity, which may explain the formation of three types of distinct granites. Variations of Rb, Sr and Ba concentrations in different type granites were controlled by fractional crystallization of biotite and feldspar. Fractional crystallization of monazite, allanite and apatite resulted in LREE changes in granite, and formation of garnet mainly caused HREE changes. Granites from the Xihuashan mining area have relatively high εd（t） values （-9.77 to -55.46）, indicating that they were probably generated by partial melting of underlying Proterozoic metasedimentary rocks with minor addition of juvenile crust or mantlederived magmas.

关键词： U-Pb dating of zircon Geochemistry Nd isotope petrogenesis of Xihuashan granite Nanling region

Exploiting articulatory features for pitch accent detection

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第11期14卷 835-844页

作者： junhong zhao Ji XU Wei-qiang ZHANG Hua YUAN Jia LIU Shanhong XIA State Key Laboratory of Transducer Technology Institute of ElectronicsChinese Academy of Sciences University of Chinese Academy of Sciences National Laboratory for Information Science and Technology Department of Electronic EngineeringTsinghua University

Articulatory features describe how articulators are involved in making *** often use a more exaggerated way to pronounce accented phonemes,so articulatory features can be helpful in pitch accent *** of using the actual articulatory features obtained by direct measurement of articulators,we use the posterior probabilities produced by multi-layer perceptrons(MLPs) as articulatory *** inputs of MLPs are frame-level acoustic features pre-processed using the split temporal context-2(STC-2) *** outputs are the posterior probabilities of a set of articulatory *** posterior probabilities are averaged piecewise within the range of syllables and eventually act as syllable-level articulatory *** work is the first to introduce articulatory features into pitch accent *** the articulatory features extracted in this way,together with other traditional acoustic features,can improve the accuracy of pitch accent detection by about 2%.

关键词： Articulatory features Pitch accent detection Prosody Computer-aided language learning(CALL) Multi-layer perceptron(MLP)

Petrogenesis and Tectonic Implications of the Tertiary Choke Shield Basalt and Continental Flood Basalt from the Central Ethiopian Plateau

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Journal of Earth Science 2023年第1期34卷 86-100页

作者： Junaid Khan Huazhou Yao junhong zhao Qiwei Li Wenshuai Xiang Junsheng Jiang Asma Tahir Institute of Geological Survey China University of GeosciencesWuhan430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan430074China Faculty of Earth Sciences China University of GeosciencesWuhan430074China Wuhan Center China Geological SurveyWuhan430205China

The voluminous Choke Shield basalts and flood basalts are distributed in the central Ethiopian *** are tholeiitic in composition and have OIB-like geochemical *** ca.23 Ma Choke Shield basalts have SiO_(2)(47.1 wt.%-59.6 wt.%),MgO(1.01 wt.%-7.8 wt.%),Na_(2)O+K_(2)O(2.7 wt.%-8.4 wt.%),and display right inclined REE patterns((La/Yb)N=21.4-24.2) with enrichment of Nb,Ta,Zr,Hf and Pb in the primitive mantle-normalized trace element *** show low initial ^(87)Sr/^(86)Sr ratios(0.703 47-0.703 77) and high ε_(Nd)(t) values(+4.4 to+5.0).In comparison,the 24Ma high-Ti(HT1) flood basalts have SiO_(2)(38.9 wt.%-50.8 wt.%),MgO(3.9 wt.%-11.4 wt.%),Na_(2)O+K_(2)O(1.6 wt.%-5.8 wt.%), and display right inclined REE patterns((La/Yb)N=24-130.3) with enrichment of Nb,Ta,Zr,Hf,and *** also show low initial ^(87)Sr/^(86)Sr ratios(0.703 30-0.704 44) and highε_(Nd)(t) values(+2.2 to+5.3).Both types of basalts were contaminated by minor crustal materials and underwent fractional crystallization of clinopyroxene,plagioclase,olivine,and minor Fe-Ti *** Choke Shield basalts were generated by 1%-5% melting of garnet-spinel to phlogopite-bearing spinel lherzolite in a shallow zone of the mantle plume,while the flood basalts were formed by <20% melting of amphibole-bearing garnet to garnet-spinel lherzolite in a deeper zone of the same mantle *** mantle source beneath the central Ethiopian Plateau was significantly heterogeneous during the *** was characterized by EMI and EMII end-members that were formed by the metasomatism of the different components.

关键词： basalt shield basalt continental flood basalt Ethiopian Plateau mantle plume

A High-Accuracy BiCMOS Constant Current Charge Circuit

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A High-Accuracy BiCMOS Constant Current Charge Circuit

Facile synthesis of polypyrrole nanowires for high-performance supercapacitor electrode materials

2005 6th International Conference on ASIC

作者： Chen Fuji Lai Xinquan Li Yushan zhao junhong Institute of Electronic CAD Xidian University

ISBN: (纸本)0780392108

＜正＞A BiCMOS constant current circuit applied to charge management ASIC is presented in this *** circuit has advantages with respect to wide range in operation voltage,high accuracy in trickle current and constant current,conveniences in ***,the current sensing resistor connecting,which consists of high-side current sensing and low-side current sensing,is *** integrated circuit has been implemented using 0.6um BiCMOS technology.

关键词： charge management BiCMOS constant current charge trickle current

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Progress in Natural Science:Materials International 2016年第3期26卷 237-242页

作者： junhong zhao Jinping Wu Bing Li Weimin Du Qingli Huang Mingbo Zheng Huaiguo Xue Huan Pang College of Chemistry and Chemical Engineering Anyang Normal University College of Chemistry and Chemical Engineering Yangzhou University

Polypyrrole nanowires are facile synthesized under a mild condition with FeClas an oxidant. Polypyrrole nanowires with the width of 120 nm form many nanogaps or pores due to the intertwined nanostructures. More importantly, PPy nanowires were further applied for supercapacitor electrode *** electrochemical testing, it was observed that the PPy nanowire based electrode showed a large specific capacitance(420 Fg, 1.5 Ag) and good rate capability(272 Fg, 18.0 Ag), which is larger than that of most of published results. The as-prepared electrode can work well even after 8000 cycles at 1.5 Ag.

关键词： Polypyrrole Nanowire Supercapacitor Electrode material