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Science China Earth Sciences 2012年第10期55卷 1706-1715页

作者： DING xuan fang NianQiao School of the Marine Sciences China University of Geosciences Beijing 100083 China

Based on an analysis of δ18O and δ13C, the planktonic foraminiferal assemblage, and sedimentary grain size, and the study of multiproxy data such as paleothermocline depth, paleoproductivity, and paleosalinity during the last glaciation in core MD98-2182 from the central equatorial western Pacific warm pool, together with the data from other sites in this region, we found that sedimentary rates, terrestrial sediment grain size distribution, and paleoproductivity were markedly influenced by glacial-interglacial sea level changes in the study area. In late Marine Isotope Stage 3 （MIS3）, which was affected by glaciation and southeast summer monsoon action restricted by precession-modulated insolation, sedimentary rates and the coarse grain content of the terrestrial sediment in the study area were the highest in the past -38 ka BP, and paleoproductivity was higher during late MIS3 than the Last Glacial Maximum. A La Nifia state dominated in the two intervals of late MIS3 and the early Holocene, and the thermocline deepened. Correlated with the strong East Asian winter monsoon in the glacial period, an El Nifio state dominated during MIS2, the thermocline shoaled, and the sea surface salinity （SSS） trended lower from the west to the east owing to the precipitation zone as the locus of atmospheric convection shifted eastward.

关键词： western equatorial Pacific Ocean last glaciation sea level monsoon El Nifio

Adaptive segmentation of digital mammograms through reinforcement learning

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光学精密工程 2005年第5期13卷 575-583页

作者： LIU Xin-yue fang Xiao-xuan HUANG Lian-qing Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of SciencesChangchun 130033 China China-Japan Union Hosptial of Jilin University Changchun 130033China

An approach based on reinfocement learning for the automated segmentation is presented. The approach consists of two modules:segmentation module and learning module. The segmentation module uses the region-growing algorithm combined with the smooth filtering and the morphological filtering to segment mammograms. The learning module uses the segmentation output as the feedback to learn to select the optimal parameter settings of the segmentation algorithm according to the image properties using reinforcement learning techniques. The approach can adapt itself to various kinds of mammograms through training and therefore obviates the tedious and error-prone tuning of parameter settings manually. Quantitative test results show that the approach is accurate for several kinds of mammograms. Compared to previously proposed approaches,the approach is more adaptable to different mammograms.

关键词：适应性分割平滑性计算机控制系统程序设计

Preparation of three-dimensionally ordered macroporous perovskite materials

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Chinese Science Bulletin 2011年第20期56卷 2156-2161页

作者： fang JunFei xuan YiMin LI Qiang School of Power Engineering Nanjing University of Science & TechnologyNanjing 210094China

In this paper,we use La0.8Sr0.2MnO3 and La0.7Ca0.2Sr0.1MnO3 as examples to demonstrate a preparation method for threedimensionally ordered macroporous(3DOM) perovskite thermochromic *** spheres with an average diameter of 220 nm were self-assembled into a three-dimensionally ordered colloidal crystal template.A mixed metal nitrate solution prepared using La(NO3) 3·6H2O,Ca(NO3) 2·4H2O,Sr(NO3) 2,Mn(CH3COO) 2·4H2O and an ethanol precursor was used to fill the interstitial voids of the polystyrene colloidal crystal templates.3DOM La0.8Sr0.2MnO3 and La0.7Ca0.2Sr0.1MnO3 materials were then obtained after the sphere templates were removed via drying and *** results show that the framework of the 3DOM materials can have different thicknesses and pore shrinkage rates by varying the filling *** addition,the Curie temperatures of the 3DOM and bulk La0.8Sr0.2MnO3 materials can be varied by altering the preparation method.

关键词：三维有序大孔变色材料制备方法钙钛矿 La(NO3)3 聚苯乙烯球 3DOM 胶体晶体

Regional features of topographic relief over the Loess Plateau,China:evidence from ensemble empirical mode decomposition

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Frontiers of Earth Science 2020年第4期14卷 695-710页

作者： Yongjuan Liu Jianjun Cao Liping Wang xuan fang Wolfgang Wagner School of Environment Science and Spatial Informatics China University of Mining and TechnologyXuzhou221116China School of Geography Science/Key Laboratory of Virtual Geographic Environment of Ministry of Education Nanjing Normal UniversityNanjing210023China School of Environmental Science Nanjing Xiaozhuang UniversityNanjing211171China Department of Geodesy and Geoinformation Vienna University of TechnologyVienna1040Austria

Landforms with similar surface matter compositions,endogenic and exogenic forces,and development histories tend to exhibit significant degrees of self-similarity in morphology and spatial *** loess hill-gully areas,ridges and hills have similar topographic relief characteristics and present nearly periodic variations of similar repeating structures at certain spatial scales,which is termed the topographic relief period(TRP).This is a relatively new concept,which is different from the degree of relief,and describes the fluctuations of the terrain from both horizontal and vertical(cross-section)perspectives,which can be used for in-depth analysis of 2-D topographic relief *** technique provides a new perspective for understanding the macro characteristics and differentiation patterns of loess *** investigate TRP variation features of different landforms on the Loess Plateau,China,by extracting catchment boundary profiles(CBPs)from 5 m resolution digital elevation model(DEM)*** profiles were subjected to temporal-frequency analysis using the ensemble empirical mode decomposition(EEMD)*** results showed that loess landforms are characterized by significant regional topographic relief;the CBP of 14 sample areas exhibited an overall pattern of decreasing TRPs and increasing topographic relief spatial frequencies from south to *** to the TRPs and topographic relief characteristics,the topographic relief of the Loess Plateau was divided into four types that have obvious regional *** findings of this study enrich the theories and methods for digital terrain data analysis of the Loess *** study should undertake a more in-depth investigation regarding the complexity of the region and to address the limitations of the EEMD method.

关键词： catchment boundary profile topographic relief period ensemble empirical mode decomposition Loess Plateau

Improvement of saponification extraction method for fatty acids separation from geological samples

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Acta Geochimica 2016年第2期35卷 148-155页

作者： Jiang Chang Yanqing Xia Suping Ma xuan fang Minzhuo Sun Key Laboratory of Petroleum Resources Gansu Province/Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of SciencesLanzhou 730000 People's Republic of China University of Chinese Academy of Sciences Beijing 100049People's Republic of China

The conventional saponification method could result in lower recoveries and artificial changes of longchain fatty acids. The main reason is the error judgment of the intermediate layer suspended between the aqueous and organic layer during the liquid–liquid extraction *** study shows that the intermediate layer consists of lots of medium- to long-chain carboxylic salts for their special physical and chemical properties. An improved saponification extraction method is also developed and the results show that the carboxylic salts distributed in the intermediate layer could be obtained completely, which greatly enhances the authenticity and accuracy of fatty acid analysis. Additionally, the possible reasons of formation of the intermediate layer are also discussed.

关键词： Fatty acid Separation Saponificationextraction Carboxylic salt Geological sample

Planetary nebulae in the circumnuclear region of M31:a spectroscopic sample

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Research in Astronomy and Astrophysics 2018年第11期18卷 97-110页

作者： An-Qi Li Zhi-Yuan Li Hui Dong xuan fang Xiao-Jie Xu School of Astronomy and Space Science Nanjing UniversityNanjing 210046China Key Laboratory of Modern Astronomy and Astrophysics Nanjing UniversityNanjing 210046China Instituto de Astroffsica de Andalucia(CSIC) Glorieta de la Astronoma S/N18008GranadaSpain Laboratory for Space Research Faculty of ScienceUniversity of Hong KongHong KongChina Department of Earth Sciences Faculty of ScienceUniversity of Hong KongHong KongChina

Planetary nebulae(PNe) are an important tool for studying the dynamics and chemical evolution of galaxies in the Local Universe, given their characteristic bright emission line spectra. The Andromeda Galaxy(M31) provides a unique laboratory for studying PNe in the circumnuclear region,thanks to its proximity and almost uniformly low line-of-sight extinction that ensures observations with high resolution and sensitivity. Using the WIYN/Hydra multi-fiber spectrograph, we have obtained optical(4119–6882 A?) spectra of 77 PN candidates selected from Hubble Space Telescope narrow-band imaging, which are located within the central ~500 pc region of M31. Among these candidates, 49(64%) are spectroscopically observed for the first time. The spectra of 300 previously known PNe and H Ⅱ regions, which primarily reside in the disk, are also taken for comparison. All 77 circumnuclear PN candidates exhibit prominent emission lines, including [O Ⅲ] λ5007, [N Ⅱ] λ6583, Hα and Hβ,strongly suggesting that they are genuine PNe. We measured the line fluxes, radial velocities and line widths for all objects, and found that the radial velocities of the circumnuclear PNe generally trace rotation of the inner bulge. We also estimated a dynamical mass of ~6.4±0.5×10~9 M_⊙ enclosed within an effective galactocentric radius of 340 pc, which is compatible with the previously estimated total stellar mass in this region.

关键词： planetary nebulae: general galaxies: individual(M31)

Greenhouse gas emissions from oilfield-produced water in Shengli Oilfield,Eastern China

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Journal of Environmental Sciences 2016年第8期28卷 101-108页

作者： Shuang Yang Wei Yang Guojun Chen xuan fang Chengfu Lv Jiaai Zhong Lianhua Xue Key Laboratory of Petroleum Resources Gansu Province/Key Laboratory of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences University of Chinese Academy of Sciences

Greenhouse gas（GHG） emissions from oil and gas systems are an important component of the GHG emission inventory. To assess the carbon emissions from oilfield-produced water under atmospheric conditions correctly, in situ detection and simulation experiments were developed to study the natural release of GHG into the atmosphere in the Shengli Oilfield,the second largest oilfield in China. The results showed that methane（CH4） and carbon dioxide（CO2） were the primary gases released naturally from the oilfield-produced *** atmospheric temperature and release time played important roles in determining the CH4 and CO2emissions under atmospheric conditions. Higher temperatures enhanced the carbon emissions. The emissions of both CH4 and CO2from oilfield-produced water were highest at 27°C and lowest at 3°C. The bulk of CH4 and CO2was released from the oilfield-produced water during the first release period, 0–2 hr, for each temperature, with a maximum average emission rate of 0.415 g CH4/（m3·hr） and 3.934 g CO2/（m3·hr）, respectively. Then the carbon emissions at other time periods gradually decreased with the extension of time. The higher solubility of CO2 in water than CH4 results in a higher emission rate of CH4 than CO2over the same release duration. The simulation proved that oilfield-produced water is one of the potential emission sources that should be given great attention in oil and gas systems.

关键词： Methane Carbon dioxide Oilfield-produced water Atmospheric conditions

InAs/InAsSb type-Ⅱ superlattice with near room-temperature long-wave emission through interface engineering

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Rare Metals 2022年第3期41卷 982-991页

作者： Bo-Wen Zhang Dan fang xuan fang Hong-Bin Zhao Deng-Kui Wang Jin-Hua Li Xiao-Hua Wang Dong-Bo Wang State Key Laboratory of High Power Semiconductor Lasers School of ScienceChangchun University of Science and TechnologyChangchun 130022China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China State Key Laboratory of Advanced Materials for Smart Sensing General Research Institute for Nonferrous MetalsBeijing 100088China Department of Opto-electronic Information Science School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China

Ga-free InAs/InAsSb type-Ⅱ superlattices(T2SL) have extensive application prospective in infrared photodetectors. Achieving higher operation temperature is critical to its commercial applications. Here, a fractional monolayer alloy method was used to grow InAsSb alloy with better controlled alloy composition. The as-grown T2SL gave eleven satellite peaks and a first satellite peak with a narrow full-width-half-maximum (FWHM) of 20.5arcsec (1 arcsec=0.01592°). Strain mapping results indicated limited Sb diffusion through the As-Sb exchange process at the interface. Moreover, unlike interface states caused by the As-Sb exchange effect, this relatively clear interface was distinctive with localized states with higher activation energies of the non-radiative recombination process ((18±1) meV and (84±12) meV at different temperature ranges), which means that this interface state introduced by fractional monolayer alloy growth method can effectively suppress Auger recombination process in T2SL. Through this interface engineering of InAs/InAsSb Type-Ⅱ superlattice, it achieved detective photoluminescence (PL) signal with the center wavelength of 9μm at 250K.

关键词： InAs/InAsSb Superlattice Interface states High operation temperature emission

Fabrication and Visible Light Photocatalytic Activity of Co-doped ZnO Nanorods

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Chemical Research in Chinese Universities 2013年第6期29卷 1032-1035页

作者： LI Xue LI Jin-hua LI Shi-jun fang xuan fang fang CHU Xue-ying WANG Xiao-hua HUJia-xin College of Information Technology Jilin Agriculture University Changchun 130118 P.R.China School of Science Changchun University of Science and Technology Changchun 130022 P.R.China

Co-doped ZnO nanorods were prepared by electrochemical deposition method in aqueous solution. lb study the as-grown samples, several characterizations were carried out. The scanning electron microscopy（SEM） images show that the samples present a rod-like shape with hexagonal cross sections and roughened surthce. There is a slight shift for （002） diffraction peak of Co-doped ZnO nanorods in XRD because Co2~ ions entered into the ZnO lattice. Energy-dispersive X-ray spectroscopy（EDS） and X-ray photoelectron spectroscopy（XPS） results also show the exist of Co in the sample. Photoluminescence（PL） spectra of the samples were observed at room tempera- ture, the UV emission of Co-doped ZnO shows a slight red shift compared with that of undoped ZnO. Thus, we can reach the conclusion that Zn2＋ ions have been substituted by Co2. ions in the ZnO samples. In addition, photocatalysis property of Co-doped ZnO nanorods was investigated under the irradiation of visible light. It was found that the degradation rate of methyl orange is increased greatly nanorods. by Co-doped ZnO nanorods in comparison to undoped ZnO

关键词： Co-doped ZnO Nanorod Electrochcmical deposition Visible light Photocatalysis

Neoantigen vaccine:An emerging immunotherapy for hepatocellular carcinoma

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World Journal of Gastrointestinal Oncology 2021年第7期13卷 673-683页

作者： Pu Chen Qiong-xuan fang Dong-Bo Chen Hong-Song Chen Peking University Hepatology Institute Beijing Key Laboratory of Hepatitis C and Immunotherapy for Liver DiseasePeking University People’s HospitalBeijing 100044China

Tumor-specific neoantigens,which are expressed on tumor cells,can induce an effective antitumor cytotoxic T-cell response and mediate tumor *** tumor immunotherapies,neoantigen vaccines are in early human clinical trials and have demonstrated substantial *** with more neoantigens in melanoma,the paucity and inefficient identification of effective neoantigens in hepatocellular carcinoma(HCC)remain enormous challenges in effectively treating this *** this review,we highlight the current development of HCC neoantigens in its generation,screening,and *** also discuss the possibility that there are more effective neoantigens in hepatitis B virus(HBV)-related HCC than in non-HBV-related *** addition,since HCC is an immunosuppressive tumor,strategies that reverse immunosuppression and enhance the immune response should be considered for the practical exploitation of HCC *** summary,this review offers some strategies to solve existing problems in HCC neoantigen research and provide further insights for immunotherapy.

关键词： Hepatocellular carcinoma Neoantigen Hepatitis B virus Screening and identification Immunosuppression Immunotherapy