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| 1 | Pollen-recorded climate changes between 13.0 and 7.0 ^(14)C ka BP in southern Ningxia,China显示文摘A pollen record from Haiyuan section in the southern part of Ningxia revealed a detailed history of vegetation variation and associated climate changes during the period from^13.0 to^7.0 14 C ka BP.A steppe landscape under a moderately dry(and probably cool)condition(~12.7-~12.1 14 C ka BP)was replaced by a coniferous forest dominating the landscape under a generally wet climate from^12.1 to ~11.01 4C ka BP.This generally wet period,corresponding to the European B?lling/All?rod period,can be divided into three stages:a cool and wet stage between^12.1 and^11.4 14 C ka BP,a mild and rela- tively dry stage between^11.4 and^11.2 14 C ka BP,and a mild and wet stage between^11.2 and^11.0 14 C ka BP.The coniferous forest-dominated landscape was then deteriorated into steppe landscape (~11.0-~10.6 14 C ka BP)and further into a desert steppe landscape from^10.6 to^9.8 14 C ka BP,being correspondent to the European Younger Dryas period.After a brief episode of a cool and wet climate (~9.8-~9.6 14 C ka BP),a relatively mild and dry condition prevailed during the early Holocene(~9.6- ~7.6 14 C ka BP)and then a warm and humid climate started the mid-Holocene(~7.6-~7.2 14 C ka BP). | SUN AiZhi MAYuZhen FENG ZhaoDong LI Fei WU HuiNing | 2007 | Chinese Science Bulletin2007，52，8： | 6 |
| 2 | Vegetation and environmental changes in western Chinese Loess Plateau since 13.0 ka BP显示文摘从中国黄土高原的花粉记录表明植被变化和联系气候的详细历史在最后 13.0 ka BP 期间变化。在 12.1 ka BP,大草原或荒芜大草原的植被前,统治风景然后在通常湿的气候(12.111.0 ka BP ) 下面由一个具球果的森林被代替。植被被败坏进大草原风景并且进一步进在 11.0 和 9.8 ka BP 之间的一处荒芜大草原的风景。在凉爽、湿的气候(9.89.6 ka BP ) 的一个简短事件以后,一个相对温和、干燥的条件在早 Holocene (9.67.6 ka BP ) 期间占优势。温暖、潮湿的时期的最赞成的气候在或者在大草原之间改变的森林大草原风景和植被标记的 mid-Holocene (7.6-4.0 ka BP ) 期间发生了并且从 4.0 ~ 1.0 ka BP 荒芜大草原。 | SUN Aizhi FENG Zhaodong MA Yuzhen | 2010 | Journal of Geographical Sciences2010，20，2： | 4 |
| 3 | Effects of Industrial Relocation on Chinese Regional Economic Growth Disparities: Based on System Dynamics Modeling显示文摘The economic growth of China has led to increasing growth disparities between regions. Such disparities are uncontrolled and are severely negative symptoms in the process of economic development. On the basis of system dynamics(SD) modeling and the relationship between industrial relocation and regional economic growth, we construct a model of the interrelationship between the two aforementioned phenomena. The model is an effective and creative exploration for examining effects of industrial relocation on Chinese regional economic growth disparities. The SD model is employed in this study to build an inter-regional labor migration SD model, an inter-regional capital migration SD model, an intra-industry SD model, an intra-regional population SD model, and an intra-regional SD model which are based on realities in labor and capital flow from the view of industrial relocation. VENSIM software is utilized to perform a system simulation based on the data of the eastern, middle, and western regions from 2000 to 2010. Results show that industrial relocation gradually narrows the relative disparity in GDP among the three regions. Moreover, the absolute one is enlarged continuously. The absolute and relative disparities in per capita GDP among eastern, middle, and western regions generally exhibit decreasing trends. | WU Aizhi LI Guoping SUN Tieshan LIANG Yusheng | 2014 | Chinese Geographical Science2014，24，6： | 3 |
| 4 | Quantitative climatic reconstruction of the Last Glacial Maximum in China显示文摘Quantitative paleoclimatic reconstruction is crucial for understanding the operation and evolution of the global climate system.For example,a quantitative paleoclimatic reconstruction for the Last Glacial Maximum(18±2 ka14C,LGM)is fundamental to understanding the evolution of Earth’s climate during the last glacial-interglacial cycle.Previous quantitative palaeoclimate reconstructions in China are generally based on statistical comparison of modern pollen assemblages and modern climate data.These methods are based on the premise that vegetation-climate interactions remain the same through time,and implicitly assume that the interactions are independent of changes in seasonality and atmospheric CO2concentration.However,these assumptions may not always be valid,which may affect the reconstructions.Here,we present the results of a quantitative study of the LGM climate of China based on an improved inverse vegetation model which incorporates physiological processes combined with a new China Quaternary Pollen Database.The results indicate that during the LGM,mean annual temperature(ANNT),mean temperature of the coldest month(MTCO)and mean temperature of the warmest month in China were lower by^5.6±0.8,~11.0±1.6 and^2.6±0.9°C,respectively,compared to today,and that the changes in ANNT were mainly due to the decrease of MTCO.The ANNT decrease in southern China was^5.5±0.5°C.Mean annual precipitation was lower by^46.3±17.8 mm compared to today and was especially low in northern China(~51.2±21.4 mm)due to the decrease in summer rainfall.Comparison of our results with recent outputs from paleoclimatic modelling reveals that while the latter are broadly consistent with our estimated changes in mean annual climatic parameters,there are substantial differences in the seasonal climatic parameters.Our results highlight the crucial importance of developing seasonal simulation on paleoclimatic models,as well as the need to improve the quality of paleoclimatic reconstructions based on proxy records from geological archives. | Haibin WU Qin LI Yanyan YU Aizhi SUN Yating LIN Wenqi JIANG Yunli LUO | 2019 | Science China Earth Sciences2019，62，8： | 3 |
| 5 | Microstructure evolution and coercivity mechanism of hydrogenation-disproportionation-desorption-recombination(HDDR) treated Nd-Fe-B strip cast alloys显示文摘In this paper,we systematically investigated the microstructure evolution and coercivity mechanism of hydrogenation-disproportionation-desorption-recombination(HDDR)treated Nd-Fe-B strip cast alloys by transmission electron microscopy(TEM)and three-dimensional atom probe(3 DAP)analyses.The rodlike NdH_(2+x) phases with diameters of 10-20 nm are embedded intoα-Fe matrix,which hereditarily leads to textured grains in HDDR alloy.The migration of NdH_(2+x) from Nd-rich region toα-Fe matrix during hydrogen absorption process contributes to the uniform redistribution of Nd-rich phases after HDDR treatment The HDDR alloy with single domain grain sizes of 200-300 nm exhibits relatively low coercivity of 1.01 T that arises from pinning magnetic domain motion.The weak c-axis orientation of HDDR alloy results in a lower reverse magnetic field(coercivity)to reduce remanence to 0.Moreover,the direct contact of Nd_(2)Fe_(14)B grains and the high concentration of ferromagnetic elements(Fe content≈66.06 at%,Co content≈0.91 at%)in Nd-rich grain boundary layer lead to strong magnetostatic coupling effect among Nd_(2) Fe_(14)B grains.The nano-sized a-Fe inside Nd_(2) Fe_(14)B matrix makes the magnetization reversal easily and decreases the coercivity of HDDR alloy. | Bin Ma Xiaoqian Bao Aizhi Sun Jiheng Li Xuexu Gao | 2022 | Journal of Rare Earths2022，40，5： | 2 |
| 6 | Impulsive stabilization of second- order delay differential equations显示文摘 | Aizhi Weng Jitao Sun | 2007 | Nonlinear Analysis: Real World Applications2007，8，： | 1 |
| 7 | Impulsive stabilization of second-order nonlinear delay differential systems显示文摘 | Weng Aizhi Sun Jitao | 2009 | Applied Mathematics and Computation2009，214，1： | 1 |
| 8 | Iron-based soft magnetic composites with Mn-Zn ferrite nanoparti- cles coating obtained by sol-gel method显示文摘 | Shen Wu Aizhi Sun Wenhuan Xu | 2012 | J Magn Magn Mater2012，324，22： | 1 |
| 9 | Positive periodic solutions of first-order functional differential equations with parameter显示文摘 | Weng Aizhi Sun Jitao | | 0，，： | 1 |
| 10 | Globally Exponential Stability of Periodic Solutions for Nonlinear Impulsive Delay Systems显示文摘 | Weng Aizhi Sun Jitao | | 0，，： | 1 |
| 11 | Impulsive stabilization of second-order delay differential equations 显示文摘 | Aizhi Weng Jitao Sun | 2007 | Nonlinear Anal2007，，8： | 1 |
| 12 | Semantic analysis and retrieval of spatial data based on the uncertain ontology model in Digital Earth显示文摘Metadata are the information about and description of data.In Digital Earth,metadata become variant and heterogeneous with many uncertainties.This paper studies uncertain features in the generation and application of metadata,and two types of uncertainties(incomplete and imprecise)are described based on semantic quantitative measurement method semantic relationship quantitative measurement based on possibilistic logic and probability statistic(SRQ-PP).Moreover,in the case study,we apply two types of quantitative measurements based on SRQ-PP to describe incomplete(uncertain)knowledge and imprecise(vague)information separately in spatial data service retrieval,which in turn is helpful to identify additional potential data resources and provide a quantitative analysis of the results. | Shengtao Sun Lizhe Wang Rajiv Ranjan Aizhi Wu | 2015 | International Journal of Digital Earth2015，8，1： | 0 |
| 13 | Anisotropic characteristic in HDDR Nd_(13)Fe_(80)B_7显示文摘The function of disproportionation and desorption stages of hydrogenation-disproportionation-desorption-recombination(HDDR) process in the formation of magnetic anisotropy was studied. The results showed that degree of anisotropy (DOA) ofNd12Fe80B7 induced by appropriate HDDR process is comparable with that of Nd13Fe80-xB7M1 (M=Co, Zr or Ga), however, the moder-ate coercive force of Nd13Fe80B7 magnetic powder led to an undesirable (BH) of 104 kJ/m3 in bonded magnet. Experiments demon-strated that a relatively short disproportionation time, combined with a high desorption temperature and slow desorption rate, duringHDDR process is beneficial to anisotropy attainment, but HDDR Nd13Fe80B7 magnetic powder becomes isotropic if the dispropor-tionation time is longer than a certain period. This phenomenon strongly indicated that the origin of anisotropy in NdFeB-typeHDDR material is contributed by disproportionation stage. XRD (X-ray Diffraction) analysis and TEM (Transmission Electron Mi-croscope) observation told that no other phase except NdH2, α-Fe and Fe2B has been found in the disproportionation step. The for-mation of HDDR Nd13Fe80 B7 anisotropy might be related to the early lamella disproportionation structure. | Jingzhi Han, Aizhi Sun, Yaofu Xiao, Xubo Liu, and Run WangMaterials Science and Engineering School, University of Science and Technology Beijing, Beijing 100083, China | 2003 | Journal of University of Science and Technology Beijing2003，10，3： | 0 |
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