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A first-order dynamical model of hierarchical triple stars and its application

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Research in Astronomy and Astrophysics 2015年第11期15卷 1857-1866页

作者： Xing-Bo Xu Fang Xia Yan-ning fu Purple Mountain Observatory Chinese Academy of Sciences University of Chinese Academy of Sciences

For most hierarchical triple stars, the classical double two-body model of zeroth-order cannot describe the motions of the components under the current observational accuracy. In this paper, Marchal＇s first-order analytical solution is implemented and a more efficient simplified version is applied to real triple stars. The results show that, for most triple stars, the proposed first-order model is preferable to the zerothorder model both in fitting observational data and in predicting component positions.

关键词： hierarchical triple fitting simplified stars dynamical Delaunay positions observational coordinate

A Survey on 3D Visual Tracking of Multicopters

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International Journal of Automation and computing 2019年第6期16卷 707-719页

作者： Qiang fu xiang-Yang Chen Wei He School of Automation and Electrical Engineering University of Science and Technology BeijingBeijing 100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing 100083China

Three-dimensional(3 D) visual tracking of a multicopter(where the camera is fixed while the multicopter is moving) means continuously recovering the six-degree-of-freedom pose of the multicopter relative to the camera. It can be used in many applications,such as precision terminal guidance and control algorithm validation for multicopters. However, it is difficult for many researchers to build a 3 D visual tracking system for multicopters(VTSMs) by using cheap and off-the-shelf cameras. This paper firstly gives an overview of the three key technologies of a 3 D VTSMs: multi-camera placement, multi-camera calibration and pose estimation for multicopters. Then, some representative 3 D visual tracking systems for multicopters are introduced. Finally, the future development of the 3D VTSMs is analyzed and summarized.

关键词： Multicopter three-dimensional(3D)visual tracking camera placement camera calibration pose estimation

Developing China's National Emission Trading Scheme:Experiences from Existing Global Schemes and China's Pilot Programs

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Chinese Geographical Science 2018年第2期28卷 287-295页

作者： ning Bolun ZHU Yongguan XU Zhihong fu Bojie College of Natural Resources and Environment University of Chinese Academy of Sciences Bureau of International Cooperation Chinese Academy of Sciences School of Bio-molecular and Physical Sciences Griffith University State Key Laboratory of Urban and Regional Ecology Research Centre for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Urban Environment Chinese Academy of Sciences

Market-based emission trading schemes(ETSs) are widely used in the developed world to reduce greenhouse gas(GHG) emissions which are perceived as the source of global climate change. China, as the largest GHG emitter in the world, is committed to introducing an ETS to reduce emissions. Here we reviewed existing ETSs and sustainable energy policies worldwide as well as China's pilot programs. These studies were conducted in order to propose recommendations for national initiatives and strategies to be implemented in China in relation to climate change adaptation and mitigation. It has been shown that setting emission caps in the context of a national emission intensity target is difficult. However, implementing reliable systems for measurement, reporting, and verification of emissions are essential. A two-level management system(by central and provincial governments) for carbon trading is beneficial to ensure uniform standards and compliance while maintaining flexibility. Persistent political support from, and effective coordination of, policies by the government are crucial. In addition, strengthening of institutional innovation, and the establishment of a national GHG emissions information system, are of equal importance. This vital information could provide a great opportunity for China to re-define its economic growth and take global leadership in combatting climate change.

关键词： carbon dioxide (CO2) greenhouse gas emissions climate change energy policy pilot program

Unexplained huge liver infarction presenting as a tumor with bleeding: A case report

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World Journal of Clinical Cases 2020年第10期8卷 2016-2022页

作者： fu-Hai Wang ning-ning Yang Feng Liu Hu Tian Department of General Surgery The First Affiliated Hospital of Shandong First Medical UniversityJinan 250014Shandong ProvinceChina Department of Respiratory and Critical Care Medicine Shandong Provincial Chest Hospital Affiliated to Shandong UniversityJinan 250013Shandong ProvinceChina

BACKGROUND Liver infarction is a rare necrotic lesion due to the dual blood supply consisting of the hepatic artery and portal *** absence of specific clinical manifestations and imaging appearances usually leads to misdiagnosis and poor ***,the precise diagnosis of liver infarction always requires imaging studies,serum studies,and possible liver *** SUMMARY We report a case of 31-year-old man who developed a huge liver *** right upper abdominal pain and intermittent fever were the main symptoms in this *** tomography revealed a huge irregular lesion with a maximum diameter of 12.7 cm in the right lobe of the *** reconstruction was performed and no significant interruption of the main hepatic vessels was *** lesion was initially considered to be a malignant tumor with internal *** right hepatectomy was performed,and pathology indicated a rare liver *** patient recovered well and was discharged on postoperative day *** fever or abnormal liver function were reported in the subsequent 6 *** In patients with a huge liver infarction,early surgical intervention may be beneficial.

关键词： Liver infraction Liver lesions Surgery Imaging Diagnosis Case report

New perspective of Miocene marine hydrocarbon source rocks in deep-water area in Qiongdongnan Basin of northern South China Sea

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Acta Oceanologica Sinica 2012年第5期31卷 107-114页

作者： LI Wenhao ZHANG Zhihuan LI Youchuan fu ning State Key Laboratory of Petroleum Resource and Prospecting China University of PetroleumBeijing 102249China CNOOC Research Institute Beijing 100027China

Drilling wells reveal that the organic matter abundance of Miocene marine source rocks in shallow water area of the Qiongdongnan Basin is relatively low with poor hydrocarbon generation poten- tial. However, in some drilling wells of deep water area close to the central depression belt, Miocene marine source rocks with better organic matter abundance and hydrocarbon generation have been found, which have achieved better source rock standard based on the analysis of geochemical charac- teristics. Although there are no exploratory wells in deep water area of the research region, through the comparative analysis of geochemical data of several typical exploratory wells respectively from shallow water area in the basin, central depression belt margin in deep-water area of the basin and Site 1148 of deep sea drilling in the South China Sea Basin, it reveals that the tendency of the quality of source rocks becomes positive gradually from delta to bathyal environment, which then becomes negative as in deep oceanic environment. Owing to the lack of terrestrial organic matter input, the important controlling factors of Miocene marine source rocks in the Qiongdongnan Basin are ocean productivity and preservation conditions of organic matter. The element geochemistry data indicate that the tendency of the paleoproductivity and the preservation conditions of organic matter become positive as water depth increase from shallow area to bathyal area close to central depression belt. So it is speculated that there must exist high quality source rocks in the central depression area where the preservation conditions of organic matter are much better. Besides, in theory, in oxygen-poor zone of oceanic environment at the water depth 400–1 000 m, the preservation conditions of organic matter are well thus forming high-quality marine source rocks. The result- ing speculation, it is reasonable to consider that there are high hydrocarbon generation potential source rocks in bathyal environme

关键词： hydrocarbon-generation potential marine source rocks ocean productivity preserva- tion condition deep water area deep sea drilling

Radical cation salts induced domino reaction of anilines with enol ethers:Synthesis of 1,2,3,4-tetrahydroquinoline derivatives

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Chinese Chemical Letters 2011年第6期22卷 671-674页

作者： Xiao Dong Jia Yan Ren Cong Dde Huo Wen Juan Wang xiang ning Chen Qiong fu Xi Cun Wang Key Laboratory of Eco-Environment-Related Polymer Materials Ministry of EducationGansu Key Laboratory of Polymer Materials College of Chemistry and Chemical EngineeringNorthwest Normal UniversityLanzhou 730070China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhou 730000China

A domino reaction of anilines with cyclic and acyclic enol ethers induced by catalytic amounts of TBPA^（·＋）（5 mol%） was investigated and a series of 2,4-disubstituted-1,2,3,4-tetrahydroquinolines were *** from cyclic enol ethers, when acyclic enol ethers were used in the reaction,they serve as surrogates of acetaldehyde,producing a series of 2-methyl-4- anilino-1,2,3,4-tetrahydroquinolines.A single electron transfer mechanism was proposed to rationalize the products formation.

关键词： Domino reaction Radical cation salts 1 2 3 4-Tetrahydroquinoline Enol ether

Carbon,nitrogen and phosphorus stoichiometry in Pinus tabulaeformis forest ecosystems in warm temperate Shanxi Province,north China

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Journal of Forestry Research 2018年第6期29卷 1665-1673页

作者： ning Wang Fengzhen fu Baitian Wang Ruijun Wang College of Agronomy Heilongjiang Bayi Agricultural UniversityDaqing 163319HeilongjiangPeople’s Republic of China Daqing Forestry Bureau Daqing 163002HeilongjiangPeople’s Republic of China Soil and Water Conservation School Beijing Forestry UniversityBeijing 100083People’s Republic of China

Although carbon(C), nitrogen(N), and phosphorous(P) stoichiometric ratios are considered good indicators of nutrient excess/limitation and thus of ecosystem health, few reports have discussed the trends and the reciprocal effects of C:N:P stoichiometry in plant–litter–soil systems. The present study analyzed C:N:P ratios in four age groups of Chinese pine, Pinus tabulaeformis Carr., forests in Shanxi Province, China: plantation young forests(AY,<20 year-old); plantation middle-aged forests(AM, 21–30 year-old); natural young forests(NY,<30 year-old); and natural middle-aged forests(NM,31–50 year-old). The average C:N:P ratios calculated for tree, shrub, and herbaceous leaves, litter, and soil(0–100 cm) were generally higher in NY followed by NM,AM, and AY. C:N and C:P ratios were higher in litter than in leaves and soils, and reached higher values in the litter and leaves of young forests than in middle-aged forests;however, C:N and C:P ratios were higher in soils of middle-aged forests than in young forests. N:P ratios were higher in leaves than in litter and soils regardless of stand age; the consistent N:P<14 values found in all forests indicated N limitations. With plant leaves, C:P ratios were highest in trees, followed by herbs and shrubs, indicating a higher efficiency in tree leaf formation. C:N ratios decreased with increasing soil depth, whereas there was no trend for C:P and N:P ratios. C:N:P stoichiometry of forest foliage did not exhibit a consistent variation according to stand age. Research on the relationships between N:P, and P, N nutrient limits and the characteristics of vegetation nutrient adaptation need to be continued.

关键词： Pinus tabulaeformis Carr. Forest ecosystem Content of carbon Nitrogen and phosphorus Ecological stoichiometry Warm temperate zone China

THE IMPACT OF MOUNTAIN TO BASIN WINDS ON THE DIURNAL VARIATION IN FOG OVER THE SICHUAN BASIN, CHINA

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Journal of Tropical Meteorology 2019年第2期25卷 257-268页

作者： ZHANG fu-ying LIU Hai-wen ZHU Yu-xiang ZHAO Liang DUAN Bo-long fu ning Nanjing University of Information Science & Technology Department of Aviation Meteorology Civil Aviation University of China CMA Training Center China Meteorological Administration LASG Institute of Atmospheric Physics Chinese Academy of Sciences Lanzhou Central Meteorological Observatory

There is an increased demand for the accurate prediction of fog events in the Sichuan Basin(SCB) using numerical methods. A dense fog event that occurred over the SCB on 22 December 2016 was investigated. The results show that this dense fog event was influenced by the southwest of a low pressure with a weak horizontal pressure gradient and high relative humidity. This fog event showed typical diurnal variations. The fog began to form at 1800 UTC on 21 December 2016(0200 local standard time on 22 December 2016) and dissipated at 0600 UTC on 22 December 2016(1400 local standard time on 22 December 2016). The Weather Research and Forecasting model was able to partially reproduce the main features of this fog event and the diurnal variation in the local mountain to basin winds. The simulated horizontal visibility and liquid water content were used to characterize the fog. The mountain to basin winds had an important role in the diurnal variation of the fog event. The positive feedback mechanism between the fog and mountain to basin winds was good for the formation and maintain of the fog during the night. During the day, the mountain to basin wind displayed a transition from downslope flows to upslope flows. Water vapor evaporated easily from the warm, strong upslope winds, which resulted in the dissipation of fog during the day. The topography surrounding the SCB favored the lifting and condensation of air parcels in the lower troposphere as a result of the low height of the lifting condensation level.

关键词： mountain to basin winds fog events weather research and forecasting simulations Tibetan Plateau

Density functional Theory Study on Spin States of LaCoO3 at Room Temperature

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Chinese Journal of Chemical Physics 2014年第3期27卷 274-278页

作者： xiang-bo Zhang Gang fu Hui-lin Wan State Key Laboratory for Physical Chemistry of Solid Surfaces Department of Chemistry College ofChemistry & Chemical Engineering Xiamen University Xiamen 361005 China

The electronic structure of the perovskite LaCoO3 at room temperature structure （293 K） was calculated by using PBE, PBE＋U and HSE. Different spin configurations have been considered. Our calculations showed that the choice of the Hubbard U parameter in DFT＋U and mixing factor α in HSE significantly influenced the band gap as well as relative energies. For the spin exited states, the optimal value for U and α were 3.0 eV and 0.05, respectively. Our calculation also emphasized that when U〉5.0 eV, PBE＋U would lead to unreasonable electronic structure and energy order.

关键词： Perovskite LaCoO3 Density functional theory