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Stable carbon and oxygen isotopes of four planktonic foraminiferal species from core-top sediments of the Indonesian throughflow region and their significance

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Acta Oceanologica Sinica 2016年第10期35卷 63-75页

作者： ZHANG Peng ZURAIDA Rina XU Jian YANG Ce State Key Laboratory of Continental Dynamics Northwest UniversityXi'an 710069China Institute of Cenozoic Geology and Environment Department of GeologyNorthwest UniversityXi'an 710069China Marine Geology Institute Bandung 40174Indonesia

Horizontal and vertical distributions of δ^18 and δ^13 were investigated in shells of four planktonic foraminiferal species, Globigerinoides ruber, Globigerinoides sacculifer, Pulleniatina obliquiloculata and Neogloboquedrina dutertrei, from a total of 62 core-top sediment samples from the Indonesian throughflow region. Results were compared to modern hydrologic conditions in order to explore potential of proxies in reconstructing fluvial discharge and upper ocean water column characteristics in this region. Our results show that, in the Makassar Strait, both of depleted δ^18 and δ^13 of these four species were linked to freshwater input. In the Bali Sea,however, depleted δ^18 and δ^13 for these species may be due to different reasons. Depleted δ^18 was a result of freshwater input and as well influenced by along-shore currents while depleted δ^13 was more likely due to the Java-Sumatra upwelling. Comparison of shell δ^18 records and hydrographic data of World Ocean Atlas 2005 suggests that G. ruber and G. sacculifer calcify within the mixed-layer, respectively at 0–50 m and 20–75 m water depth, and P. obliquiloculata and N. dutertrei within the upper thermocline, both at 75–125 m water depth. *** calcifies at slightly deeper water depth than P. obliquiloculata does. In general, δ^13 values of both *** and G. sacculifer are larger than those of P. obliquiloculata and N. dutertrei at all sites, possibly related to depth habitats of these species and vertical distribution of nutrients in the Indonesian throughflow region.

关键词： planktonic foraminiferal δ^18O and δ^13C calcification depth freshwater input Java-Sumatra upwelling Indonesian throughflow region

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Geochemical characteristics from tests of four modern planktonic foraminiferal species in the Indonesian Throughflow region and their implications

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Geoscience Frontiers 2019年第2期10卷 505-516页

作者： Peng Zhang Rina Zuraida Yair Rosenthal Ann Holbourn Wolfgang Kuhnt Jian Xu Institute of Cenozoic Geology and Environment State Key Laboratory of Continental DynamicsDepartment of GeologyNorthwest University Marine Geology Institute Department of Marine and Coastal Sciences RutgersThe State University of New Jersey Institute of Geosciences Christian-Albrechts-University

Test geochemistry of planktonic foraminifera is an indispensable tool in reconstructing past ocean hydrological changes. It is essential to investigate region-specific implications of test geochemistry,although those established from other regions can be broadly applied. In this study, characteristics of6180 and Mg/Ca from tests of four planktonic foraminiferal species, Globigerinoides ruber sensu stricto(s.s.), Globigerinoides sacculifer, Pulleniatina obliquiloculata and Neogloboquadrina dutertrei, from 60 coretop sediment samples retrieved from the Indonesian Throughflow(ITF) region were studied. These geochemical data were compared with modern hydrographic profiles in order to assess their relations and to investigate potential implications of test geochemical parameters in reconstructing past oceanographic change in the ITF region. Calcification depths of these four species were first estimated based on comparison between measured test δ180 and predicted calcite δ^(18)O that was calculated from modern temperature and salinity. The results indicate that G. ruber s.s. and G. sacculifer calcify within the mixedlayer at 0-50 m and 20-75 m, respectively, whereas P. obliquiloculata and N. dutertrei calcify within the thermocline at around 75 to 125 m. A combined study of excess Mg/Ca(difference between measured and predicted Mg/Ca) and salinity suggests that salinity exerts a negligible impact on test Mg/Ca of these foraminiferal species in the ITF region. Comparison of test Mg/Ca-derived temperatures with temperature profiles of the upper 200 m of the water column from the seas of the ITF region also indicate calcification depths of these species, which match well with the above estimations using test δ^(18)O. It further indicates that G. sacculifer may be more sensitive in reflecting changes in the depth of the mixedlayer, highlighting a potential use of Mg/Ca temperature difference between G. ruber s.s. and G. sacculifer in reconstructing the depth of the mixed-lay

关键词： Test geochemistry Multi-species Planktonic foraminifera Core-top sediments Indonesian Throughflow region

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Effect of surface morphology on wettability conversion

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Journal of Advanced Ceramics 2016年第4期5卷 284-290页

作者： Xia KONG Yawei HU Xiaofang WANG Wei PAN College of Chemistry and Chemical Engineering Shaanxi University of Science and TechnologyXi'an Shaanxi 710021 China State Key Laboratory of New Ceramics and Fine Processing Tsinghua University Beijing 100084 China

A hierarchical structural surface of TiO2 film with reversibly light-switchable wettability between superhydrophobicity and superhydrophilicity on metal substrate was fabricated through simply dip-coating method from TiO2 precursor solution containing TiO2 nanoparticles with the average diameter 25 nm (P25),followed by heat-treatment and modification with fluoroalkylsilane (FAS) *** morphology,phase and crystallographic structure,and chemical composite of the as-prepared TiO2 film were characterized by scanning electron microscopy (SEM),X-ray diffraction (XRD),and X-ray photoelectron spectroscopy (XPS).The wettability of TiO2 film was characterized by a drop shape *** water contact angle of superhydrophobic TiO2 film was up to 165.6°.Under UV irradiation,the water contact angle decreased and the superhydrophobic TiO2 film became superhydrophilic because of hydroxyl groups absorption on the TiO2 ***,the surface morphology of TiO2 film,which resulted from the TiO2 nanoparticles added in TiO2 precursor solution,had a significant effect on the wettability conversion of TiO2 film and enhanced the switch from hydrophobicity to *** wettability could be reversibly switched between superhydrophobicity and superhydrophilicity via alternation of UV exposure and dark storage.

关键词： TiO2 morphology wettability reverse conversion

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Enhancement of hydroxyapatite dissolution through structure modification by Krypton ion irradiation

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Journal of Materials Science & technology 2020年第3期38卷 148-158页

作者： Hui Zhu Dagang Guo Hang Zang Dorian AHHanaor Sen Yu Franziska Schmidt Kewei Xu State Key Laboratory for Mechanical Behavior of Materials School of Material Science and EngineeringXi’an Jiaotong UniversityXi’an710049China School of Nuclear Science and technology Xi’an Jiaotong UniversityXi’an710049China Fachgebiet Keramische Werkstoffe/Chair of Advanced Ceramic Materials Institut für Werkstoffwissenschaften und-TechnologienTechnische Universit?t BerlinHardenbergstra?e 4010623BerlinGermany shaanxi Key Laboratory of biomedical metal materials Northwest Institute for Non-ferrous Metal ResearchXi’an710016China

Hydroxyapatite(HA)synthesized by a wet chemical route was subjected to heavy ion irradiation,using4 Me V Krypton ion(Kr17+)with ion fluence ranging from 1×1013 to 1×1015 ions/*** incidence X-ray diffraction(GIXRD)results confirmed the phase purity of irradiated HA with a moderate contraction in lattice parameters,and further indicated the irradiation-induced structural disorder,evidenced by broadening of the diffraction ***-resolution transmission electron microscopy(HRTEM)observations indicated that the applied Kr irradiation induced significant damage in the hydroxyapatite ***,cavities were observed with their diameter and density varying with the irradiation fluences,while a radiation-induced crystalline-to-amorphous transition with increasing ion dose was *** and X-ray photoelectron spectroscopy(XPS)analysis further indicated the presence of irradiationinduced *** release from pristine and irradiated materials following immersion in Tris(p H 7.4,37?)buffer showed that dissolution in vitro was enhanced by irradiation,reaching a peak at 0.1 *** examined the effects of irradiation on the early stages of the mouse osteoblast-like cells(MC3 T3-E)response.A cell counting kit-8 assay(CCK-8 test)was carried out to investigate the cytotoxicity of samples,and viable cells can be observed on the irradiated materials.

关键词： High energy heavy ion irradiation Hydroxyapatite HRTEM Crystal defects In vitro dissolution Cell compatibility

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Passivation of Ge surface treated with trimethylaluminum and investigation of electrical properties of HfTiO/Ge gate stacks

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Journal of Materials Science & technology 2017年第8期33卷 901-906页

作者： Juan Gao Gang He Dongqi Xiao Peng Jin Shanshan Jiang Wendong Li Shuang Liang Li Zhu School of Physics and Materials Science Radiation Detection Materials & Devices Lab Anhui University School of Mechanics and Optoelectric Physics Anhui University of Science and Technology

In the current work, in situ surface passivation Ge substrate by using trimethylaluminum（TMA） prior to HfTiO films deposition and electrical properties of HfTiO/Ge gate stacks have been investigated by X-ray photoelectron spectroscopy（XPS） and electrical measurements systematically. Based on analysis from XPS measurements, it has been confirmed that the interfacial layer of HfTiO/Ge gate stack has been suppressed effectively after 20 half-ALD cycles TMA pretreatment. Electrical properties of metal-oxidesemiconductor（MOS） capacitor based on HfTiO gate dielectrics have shown that the MOS capacitor with20 cycles TMA cleaning exhibits the lowest interface state density（~7.56 eV^（-1）cm^（-2）） and the smallest leakage current（~2.67 × 10^（-5）A/cm^2）. Correspondingly, the leakage current conduction mechanisms for MOS capacitor device with 20 cycles TMA cleaning also have been discussed in detail.

关键词： Germanium Trimethylaluminum Atomic layer deposition Electrical properties

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Hydrothermal synthesis and up-conversion luminescence of Ho^(3+)/Yb^(3+)co-doped CaF_2

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chinese Physics B 2014年第6期23卷 271-277页

作者：杨征郭崇峰陈叶青李琳李婷郑仲铉 National Key Laboratory of Photoelectric technology and Functional Materials (Culture Base) in shaanxi Province Institute of Photonics & Photon-Technology Northwest University Department of Physics Pukyong National University

CaF2：Ho3＋/Yb3＋ nano-particles with intense green up-conversion （UC） luminescence are successfully synthesized via a facile hydrothermal approach by using NH4F as the fluoride source and Na2EDTA as a chelating reagent. Powder X- ray diffraction （XRD）, transmission electron microscopy （TEM）, field emission scanning electron microscopy （FE-SEM）, and UC emission spectra are used to characterize the structures, shapes, and luminescent properties of the samples. The effects from fluoride sources and chelating reagents on the formations of CaF2 nano-particles are investigated, and the for- mation process is also deduced. Under the excitation of a 980-nm laser diode, the samples each show a green up-conversion emission centered at 540 nm corresponding to the 5S2/5F4-＋518 transitions of Ho3＋. Moreover, the UC mechanisms of Ho3＋/Yb3＋ co-doped CaF2 nano-particles are also discussed.

关键词： CaF2 nano-particles up-conversion hydrothermal synthesis

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Liquid chemical looping gasification of biomass:Thermodynamic analysis on cellulose

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chinese Journal of Chemical Engineering 2021年第9期34卷 79-88页

作者： Wei Guo Bo Zhang Jie Zhang Zhiqiang Wu Yaowu Li Bolun Yang shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China Nuclear Power Institute of China Chengdu 610213China

Liquid chemical looping technology is an innovation of chemical looping conversion *** liquid metal oxide as the oxygen carrier during gasification process could prolong the service life of oxygen carrier and improve the process *** this paper,based on Gibbs minimum free energy method,the thermodynamic characteristics of biomass liquid chemical looping gasification were *** and lignin,the main components of biomass,were taken as the research *** oxide and antimony oxide were selected as liquid oxygen *** results showed that when the temperature increased from 600℃to 900℃,the output of H_(2)and CO in the products of cellulose gasification increased from 0.5 and 0.3 kmol to 1.3 and 2.6 kmol *** ratios of oxygen carriers to gasification raw materials had the best molar *** addition of steam in the system was beneficial to the increase of H_(2)content and the increase of H_(2)/CO molar ***_(2)O_(3)and Sb_(2)O_(3)with different mass ratios were used as mixed oxygen *** simulation results showed that the gasification temperature of biomass with different mixed oxygen carriers had the same equilibrium trend *** could be seen from the results of product distribution that the influence of the mixing ratio of Bi_(2)O_(3)and Sb_(2)O_(3)on gas product distribution could be *** results could provide simulation reference and data basis for subsequent research on liquid chemical looping gasification.

关键词： Liquid chemical looping conversion Biomass Thermodynamics Product distribution Oxygen carrier Simulation

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Chemical looping gasification of maceral from low-rank coal: Products distribution and kinetic analysis on vitrinite

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chinese Journal of Chemical Engineering 2021年第8期34卷 233-241页

作者： Bo Zhang Bolun Yang Wei Guo Song Wu Jie Zhang Zhiqiang Wu shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an710049China

The product distribution and kinetic analysis of low-rank coal vitrinite were investigated during the chemical looping gasification(CLG)*** acid washing method was used to treat low-rank coal,and the density gradient centrifugation method was adopted to obtain the coal *** combining thermogravimetric analysis and online mass spectrometry,the influence of the heating rate and oxygen carrier(Fe2O3)blending ratio on product distribution was *** macroscopic kinetic parameters were solved by the Kissinger-Akahira-Sunose(KAS)method,and the main gaseous product formation kinetic parameters were solved by the iso-conversion *** results of vitrinite during slow heating chemical looping gasification showed that the main weight loss interval was 400–600℃,and the solid yield of sample vitrinite-Fe-10 at different heating rates was 64.30%–69.67%.When b=20℃·min^(-1),the maximum decomposition rate of vitrinite-Fe-10 was 0.312%*** addition of Fe2O_(3)reduced the maximum decomposition rate,but by comparing the chemical looping conversion characteristic index,it could be inferred that the chemical looping gasification of vitrinite might produce volatile substances higher than the pyrolysis process of vitrinite *** average activation energy of the reaction was significantly reduced during chemical looping gasification of vitrinite,which was lower than the average activation energy of 448.69 kJ·mol^(-1) during the pyrolysis process of vitrinite *** gaseous products were mainly CO and CO_(2).When the heating rate was 10℃·min^(-1),the highest activation energy for CH4 formation was 21.353 kJ·mol^(-1),and the lowest activation energy for CO formation was 9.7333 kJ·mol^(-1).This study provides basic data for exploring coal chemical looping gasification mechanism and reactor design by studying the chemical looping gasification process of coal macerals。

关键词： Coal Vitrinite Chemical looping process Gasification Products distribution Reaction kinetics

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Green up-conversion luminescence in Yb^(3+)-Pr^(3+) co-doped BaRE_2ZnO_5(RE=Y,Gd)

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Journal of Rare Earths 2013年第12期31卷 1137-1140页

作者：李琳郭崇峰焦桓李婷郑仲铉 National Key Laboratory of Photoelectric technology and Functional Materials (Culture Base) in shaanxi Province National Photoelectric Technology and Functional Materials & Application of Science and Technology International Cooperation BaseInstitute of Photonics & Photon-Technology and Department of PhysicsNorthwest University School of Chemistry & Chemical Engineering Shaanxi Normal University Department of Physics Pukyong National University

Yb3＋and Pr3＋co-doped BaRE2 ZnO5（RE=Y,Gd） up-conversion（UC） phosphors were successfully synthesized by a modified sol-gel *** processing parameters and optimal concentration of Pr3＋and Yb3＋were *** structures and luminescent properties of samples were characterized by X-ray diffraction（XRD） and photoluminescence spectra（PL）.With the excitation of 980 nm laser diode,UC spectra showed five prominent emission bands centered at 484,514,546,656 and 670 nm,which were attributed to the1I6 →3H4,3P1 →3H4,3P0 →3H5,3P0 →3F2 and3P0 →3F3 transitions of Pr3＋,*** the light of the pump power dependence,the possible UC mechanism in Yb3＋and Pr3＋co-doped BaRE2 ZnO5（RE=Y,Gd） was proposed and discussed.

关键词： phosphor up-conversion energy transfer luminescence rare earths

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Short-time Lv transform and its application for non-linear FM signal detection

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Journal of Systems Engineering and Electronics 2015年第6期26卷 1159-1168页

作者： Shan Luo Xiumei Li Guoan Bi School of Aeronautics and Astronautics University of Electronic Science and Technology of China School of Information Science and Engineering Hangzhou Normal University School of Electrical and Electronic Engineering Nanyang Technological University

A new time-frequency transform, known as short-time Lv transform （STLVT）, is proposed by applying the inverse Lv distribution to process consecutive segments of long data sequence. Compared with other time-frequency representations, the STLVT is able to achieve better energy concentration in the time-frequency domain for signals containing multiple linear and/or non-linear frequency modulated components. The merits of the STLVT are demonstrated in terms of the effects of window length and overlap length between adjacent segments on signal energy concentration in the time-frequency domain, and the required computational complexity. An application on the spectrum sensing for cognitive ratio （CR） by using a joint use of the STLVT and Hough transform （HT） is proposed and simulated.

关键词： Lv distribution time-frequency transform frequencymodulated signal spectrum sensing.

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