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Onion-structured transition metal dichalcogenide nanoparticles by laser fabrication in liquids and atmospheres

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Chinese Physics B 2022年第7期31卷 8-16页

作者： Le zhou Hongwen zhang Qian Zhao Weiping Cai Key Laboratory of Materials Physics Anhui Key Laboratory of Nanomaterials and NanotechnologyInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China

Since the discovery of transition metal dichalcogenide(TMDC)nanoparticles(NPs)with the onion-like structure,many efforts have been made to develop their fabrication *** fabrication(LF)is one of the most promising methods to prepare onion-structured TMDC(or OS-TMDC)NPs due to its green,flexible,and scalable *** this mini-review article,we systematically introduce various laser-induced OS-TMDC(especially the OS-MoS_(2))NPs,their formation mechanism,properties,and *** preparation routes mainly include laser ablation in liquids and atmospheres,and laser irradiation in *** various formation mechanisms are then introduced based on the different preparation routes,to describe the formations of the corresponding ***,some interesting properties and novel applications of these NPs are briefly demonstrated,and a short outlook is also *** review could help to understand the progress of the laser-induced OS-TMDC NPs and their applications.

关键词： transition metal dichalcogenide nanoparticles onion-like structure laser fabrication in liquids formation mechanism

Estimating the Macroeconomic Costs of CO_2 Emission Reduction in China Based on Multi-objective Programming

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Advances in Climate Change Research 2010年第1期1卷 27-33页

作者： ying Fan Xiaobing zhang Lei Zhu Center for Energy ＆ Environmental Policy Research Institute of Policy ＆ Management Chinese Academy of Sciences Beijing 100190 China

This paper estimates the macroeconornic costs of CO2 emission reduction in China employing the input-output analysis with the multi-objective programming approach. The results show that the effect of reducing CO2 emissions on China＇s economy is significant. Under the present conditions, the estimated macroeconomic costs of CO2 emission reduction in 2010 for China are approximately 3,100-4,024 RMB t-1. The stronger the abatement actions, the higher the macroeconomic costs of per unit emission reduction would be. Excavation industry, oil industry, chemical industry, and metal smelting industry have high potential to abate their CO2 emissions.

关键词： CO2 emission reduction macroeconomic cost multi-objective programming input-output analysis

Metamorphic P-T-t Path of UHT Granulites from the North Tongbai Orogen, Central China

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Journal of Earth Science 2018年第5期29卷 1116-1131页

作者： Hua Xiang Zeming zhang Liming Zhao Zengqiu Zhong Hanwen zhou Key Laboratory of Deep-Earth Dynamics Institute of Geology Chinese Academy of Geological Sciences School of Earth Sciences and Resources China University of Geosciences School of Earth Sciences China University of Geosciences

Although zircon U-Pb geochronometer has been widely used for dating metamorphism in moderate- to high-grade metamorphic rocks, it is still difficult to link the zircon U-Pb age to pressure and temperature （P-T） conditions. In this study, zircon trace elements and Hf isotopes and REE partitioning between zircon and garnet are adopted to track the formation condition of zircon in the granu- lites from North Tongbai Orogen, Central China. Combined with previous metamorphic P-T path results, a quantitative integrated anticlockwise P-T-t path was established for Tongbai granulites. These grauulites recorded an early low-P heating followed by a dramatic pressure increase. Evidence for the prograde history （M1） is provided by cordierite, orthopyroxene and biotite inclusions in garnet. The prograde metamorphism occurred at around 443±3 Ma, with P-T conditions of ca. 730-820 ℃ and 〈6 kbar. The peak metamorphic （M2） condition is 〉920 ℃ and 8.5-10 kbar and the peak metamorphism age is ca. 432±4 Ma. At around 419 Ma, the granulites suffered an amphibolite-facies retrograde metamorphism （M3）, represented by the replacement of garnet by biotite and plagioclase, and clinopyroxene by amphibole, with metamorphic condition of ca. 700℃ and ca. 7 kbar. The last retrograde metamorphism （M4） is a greenschist-facies overprint with an age of ca. 404 Ma. It is concluded that the meta- morphism of Tongbai granulite lasted for more than 40 Ma, including a stage of more than 20 Ma granulitc-facies metamorphism. The prolonged granulite-facies metamorphism resulted from the continuous northward subduction of the Shangdan oceanic crust beneath the North Qinling terrane.

关键词： granulites zircon U-Pb dating P-T-t path trace element Ln-Hf isotope Tongbai Orogen.

Modulation of field emission by small AC signals

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Science China(Technological Sciences) 2017年第12期60卷 1897-1902页

作者： YANG Jin zhang GengMin zhou HaiTao WEI JinDi CHEN YanHui SHEN ChengMin Key Laboratory for the Physics and Chemistry of Nanodevices and Department of Electronics PekingUniversity Beijing 100871 China Academy for Advanced Interdisciplinary Studies Peking University Beijing 100871 China AECC Beijing Institute of Aeronautical Materials Beijing100095 China Beijing National Laboratory of Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China Chang'an Communication Technology Co. Ltd. Beijing 102209 China

In a microwave tube the energy of electrons in an electron beam, which are usually generated by a thermionic cathode, is modulated such that it is transformed into electromagnetic wave energy. In this paper, we modulated the field emission using AC signals.A field emission current with AC components was attained by adding a small AC voltage to a high extracting DC voltage. We observed two phenomena related to the AC components of the field emission current. First, when the DC component of the extracting voltage was low, the current measured in the circuit was dominated by the displacement current. Second, besides the fundamental frequency component, higher order harmonics were also observed in the field emission current.

关键词： field emission AC modulation displacement current harmonics

Response of Pinus taiwanensis growth to climate changes at its southern limit of Daiyun Mountain, China's Mainland Fujian Province

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Science China Earth Sciences 2016年第2期59卷 328-336页

作者： CHEN Dan FANG KeYan LI yingJun DONG ZhiPeng zhang Yu zhou FeiFei Institute of Geography Key Laboratory of Humid Subtropical Eco-geographical Process (Ministry of Education)College of Geographical Sciences Fujian Normal University Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of Sciences Research Center for Scientific Development in Fenhe River Valley Taiyuan Normal University

The Pinus taiwanensis trees of a Chinese endemic species form pure forests at infertile sites in humid subtropical China, which can aid soil reservation and ecological resiliency at such sites. Herein, we used dendrochronological methods to investigate the growth patterns and their relationship with climate by analyzing 158 cores of 79 P. taiwanensis trees at 4 sites in their southernmost distribution in China's Mainland at Daiyun Mountain in Fujian Province. Tree growths at sites with favor- able conditions generally showed an age-related growth trend, which decreased from approximately 5 mm to 0.5 mm in about a century. Trees in moderately stressed environments established high growth in their juvenile periods but were highly suscep- tible to environmental stresses such as a sharp growth decline in the 1990s. The temperature in February and the moisture in July are the major limiting factors for most of the tree growths, except for a few extremely stressed P. taiwanensis trees. The growth of the dwarf P. taiwanensis trees, with all ring diameters of the first 20 years less than 4 ram, is mainly limited by the dry climate in May. Under the potential future warming trend, drought stress can be particularly threatening to these dwarf P. taiwanensis trees, which are likely to be the germplasm resources for this species in this region.

关键词： Daiyun Mountain Pinus taiwanensis Climate-growth relationships Drought Global warming

Provenance of colorless and brown volcanic glass in late Pleistocene tephra layers in the Western Philippine Sea

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Journal of Oceanology and Limnology 2024年第5期42卷 1438-1449页

作者： Fuqing JIANG Zhishun zhang Zhaohui zhang Guoliang zhang Peng HUANG Xiaojing zhou Zhifang XIONG Congying LI Tiegang LI Key Laboratory of Ocean Observation and Forecasting and Key Laboratory of Marine Geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China Institute of Marine Chemistry and Environment Ocean CollegeZhejiang UniversityZhoushan 316021China College of Marine Technology and Environment Dalian Ocean UniversityDalian 116023China Key Laboratory of Marine Sedimentology and Environmental Geology First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China

Tephra layers in the western Philippine Sea,characterized by abundant volcanic glass shards,may provide crucial evidence on the eruption history of volcanoes and tectonic evolution of the western Pacific.A 220-ka sediment core from the Benham Rise in the western Philippine Sea offers new insights into the provenance of four intercalated tephra layers(T1–T4,in chronological order)containing either colorless or brown glass *** to primitive mantle,all glass shards are enriched in large-ion lithophile elements,such as Rb,Cs,and Pb,and depleted in high field-strength elements,such as Th,Nb,and Ta,indicating a subduction-related *** colorless glass shards are characterized by high SiO_(2)(>78%)and light rare earth element(LREE)contents as well as high La/Sm ratios(>9),low FeO and MgO contents(100),pointing to a rhyolitic composition and a medium-K calc-alkaline serial *** contrast,the brown glass shards are characterized by lower SiO_(2)(<63%)and LREE contents,higher FeO,MgO,and CaO contents,lower La/Sm(<6)and Ba/Th(<75),and similar Sr/Y ratios(<15),indicating derivation from medium to high-K calc-alkaline andesite *** glass shards from layers T3(152 ka)and T4(172 ka)were correlated with volcanic deposits from the Taal and Laguna Caldera in the Maccolod Corridor,respectively,while the colorless glass shards from layers T1(36.5 ka)and T2(61.2 ka)were likely sourced from the Irosin Caldera in the Bicol *** the provenance of late Pleistocene tephra layers in the western Philippine Sea is helpful to complement a Philippine volcanic history and establish a regional tephrochronostratigraphy.

关键词： volcanic glass provenance chemical composition Philippine Sea late Pleistocene

Conflicting selection pressures on seed size and germination caused by carnivorous seed dispersers

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Integrative Zoology 2023年第5期18卷 799-816页

作者： Jifa CUI Yaqian zhang Jinyu GUO Nan WU Youbing zhou Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichangChina

Plants produce nutritious,fleshy fruits that attract various animals to facilitate seed dispersal and recruitment ***-specific differential selection of seed size by multiple frugivorous disperser assemblages may affect the subsequent germination of the ingested ***,there is little empirical evidence supporting this *** the present study,we documented conflicting selection pressures exerted on seed size and germination by five frugivorous carnivores on a mammal-dispersed pioneer tree,the date-plum persimmon(Diospyros lotus),in a subtropical *** analyses revealed that these carnivores acted as primary seed dispersers of *** also observed that seed sizes were selected based on body mass and were species-specific,confirming the“gape limitation”hypothesis;three small carnivores(the masked palm civet Paguma larvata,yellow-throated marten Martes flavigula,and Chinese ferret-badger Melogale moschata)significantly preferred to disperse smaller seeds in comparison with control seeds obtained directly from wild plants whereas the largest Asiatic black bears(Ursus thibetanus)ingested larger *** dispersed by medium-sized hog badgers(Arctonyx albogularis)were not significantly different from control ***,regarding the influence of gut passage on seed germination,three arboreal dispersal agents(martens,civets,and bears)enhanced germination success whereas terrestrial species(ferret-badgers and hog badgers)inhibited the germination process compared with undigested control *** conflicting selection pressures on seed size and germination may enhance the heterogeneity of germination dynamics and thus increase species fitness through diversification of the regeneration *** results advance our understanding of seed dispersal mechanisms and have important implications for forest recruitment and ecosystem dynamics.

关键词： fleshy fruit gut treatment seed germination seed size selection pressure

Comparison between Top and Bottom NiO-pinning Spin Valves: Effect of Interfacial Roughness on Specular Reflection

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Journal of Materials Science & Technology 2006年第3期22卷 397-400页

作者： Liang SUN Jun DU Xiaoshan WU Shiming zhou Xixiang zhang An HU National Laboratory of Solid State Microstructures Department of Physics Nanjing University Nanjing 210093 China State Key Laboratory for Surface Physics Fudan University Shanghai 200433 China Department of Physics Hong Kong University of Science ＆ Technology Kowloon Hong Kong China

Top and bottom NiO-pinning spin valves of Si/Ta/NiO/Co/Cu/Co/Ta and Si/Ta/Co/Cu/Co/NiO/Ta were prepared by magnetron sputtering, and X-ray diffraction and giant magnetoresistance （GMR） ratio were measured in the temperature range from 5 to 300 K. For the bottom spin valve, the interracial roughness at NiO/Co is much smaller than that of Co/NiO in the top one. The Co/Cu and Cu/Co interfaces have the same roughness in the bottom and the top spin valves. NiO, Co, and Cu layers have （111） preferred orientations in the top one and random orientations in the bottom one. The GMR ratio of the bottom spin valve is larger than that of the top one at all temperatures and their difference increases with decreasing temperature.

关键词： Spin valve Specular reflection Interfacial roughness

ALGORITHM OF SAR SATELLITE ATTITUDE MEASUREMENT USING GPS AIDED BY KINEMATIC VECTOR

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Journal of Electronics(China) 2007年第5期24卷 622-627页

作者： Tian Zengshan Tan ying zhang Gang The Center of Mobile ＆ Communication Chongqing University of Posts and Telecommunications Chongqing 400065 China

In this paper,in order to improve the accuracy of the Synthetic Aperture Radar (SAR) satellite attitude using Global Positioning System (GPS) wide-band carrier phase,the SAR satellite attitude kinematic vector and Kalman filter are *** the state variable function of GPS attitude determination algorithm in SAR satellite by means of kinematic vector and describing the observation function by the GPS wide-band carrier phase,the paper uses the Kalman filter algorithm to obtian the attitude variables of SAR *** the simulation results of Kalman filter algorithm with the least square algorithm and explicit solution,it is indicated that the Kalman filter algorithm is the best.

关键词： Synthetic Aperture Radar (SAR) satellite Attitude measurement Satellite attitude Kinematic vector Kalman filter