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UNDERSTANDING HREM IMAGES OF Al-Mn-Si ICOSAHEDRAL QUASICRYSTAL
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作者 闵乐泉 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1996年第2期142+140-142,共4页
提出了处理数字化图像的光滑算子。用它处理了Al-Mn-Si二十面体准晶的高分辨电子显微图,处理后的图像展示了周期结构特征,由此建立了一个平面周期模型,其Fourier变换图符合Al-Mn-Si准晶相应的电子衍射图。
关键词 图像处理 高分电子显微图 准晶 模型 Fourier变换图
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Assessment of wind products obtained from multiple microwave scatterometers over the China Seas 被引量:1
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作者 王志雄 赵朝方 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2015年第5期1210-1218,共9页
Sea surface winds (SSWs) are vital to many meteorological and oceanographic applications, especially for regional study of short-range forecasting and Numerical Weather Prediction (NWP) assimilation. Spaceborne se... Sea surface winds (SSWs) are vital to many meteorological and oceanographic applications, especially for regional study of short-range forecasting and Numerical Weather Prediction (NWP) assimilation. Spaceborne seatterometers can provide global ocean surface vector wind products at high spatial resolution. However, given the limited spatial coverage and revisit time for an individual sensor, it is valuable to study improvements of multiple microwave scatterometer observations, including the advanced scatterometer onboard parallel satellites MetOp-A (ASCAT-A) and MetOp-B (ASCAT-B) and microwave scatterometers aboard Oceansat-2 (OSCAT) and HY-2A (HY2-SCAT). These four scatterometer-derived wind products over the China Seas (0°-40°N, 105°-135°E) were evaluated in terms of spatial coverage, revisit time, bias of wind speed and direction, after comparison with ERA-Interim forecast winds from the European Centre for Medium-Range Weather Forecasts (ECMWF) and spectral analysis of wind components along the satellite track. The results show that spatial coverage of wind data observed by combination of the four sensors over the China Seas is about 92.8% for a 12-h interval at 12:00 and 90.7% at 24:00, respectively. The analysis of revisit time shows that two periods, from 5:30-8:30 UTC and 17:00-21:00 UTC each day, had no observations in the study area. Wind data observed by the four sensors along satellite orbits in one month were compared with ERA-Interim data, indicating that bias of both wind speed and direction varies with wind speed, especially for speeds less than 7 m/s. The bias depends on characteristics of each satellite sensor and its retrieval algorithm for wind vector data. All these results will be important as guidance in choosing the most suitable wind product for applications and for constructing blended SSW products. 展开更多
关键词 sea surface wind microware scatterometer spectral analysis composite sampling error analysis
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A New High-resolution Late Glacial-Holocene Climatic Record from Eastern Nanling Mountains in South China 被引量:3
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作者 XUE Jibin ZHONG Wei +3 位作者 ZHENG Yanming MA Qiaohong CAI Ying OUYANG Jun 《Chinese Geographical Science》 SCIE CSCD 2009年第3期274-282,共9页
A 350-cm-long sediment core sequence from Dahu Swamp situated in the eastern Nanling Mountains was selected for high-resolution paleoclimatic reconstruction since the Late Glacial period. The multi-proxy records of th... A 350-cm-long sediment core sequence from Dahu Swamp situated in the eastern Nanling Mountains was selected for high-resolution paleoclimatic reconstruction since the Late Glacial period. The multi-proxy records of this paper reveal several evidently dry and cold events that may coincide with the Oldest Dryas, the Older Dryas, the Younger Dryas in the late deglacial period. Two relatively wetter and warmer phases occurred in ca. 15,000-14,400 cal yr B.P. and 13,500-12,800 cal yr B.P. respectively may correspond to the Boiling and Allerod warming events. The Younger Dryas event (ca. 12,800-11,500 cal yr B.P.) revealed by multi-proxies was characterized by relatively colder and drier climate. A warmer and wetter climate, occurred in ca. 10,000~5000 cal yr B.P., was consistent with the Holoeene Optimum, which coincided with the maximum Northern Hemisphere insolation. The "8.2kyr cool event" and even the "8.8kyr cool event" were indicated as well from our sediment core. A dry mid-Holocene period (ca. 60000 3000 cal yr B.P.) indicated by multi-proxies does not follow the traditional concept of the wet mid-Holocene conditions observed in other regions in China. 展开更多
关键词 Late Glacial period HOLOCENE climatic record Dahu Swamp South China
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The ‘Two oceans and one sea' extended range numerical prediction system with an ultra-high resolution atmosphere-ocean-land regional coupled model 被引量:2
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作者 Zhang Shao-Qing Yang LIU +4 位作者 Ma Xiao-Hui Wang Hong-Na Zhang Xue-Feng Yu Xiao-Lin Lu Lv 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第4期364-371,共8页
The‘Two Oceans and One Sea’area(West Pacific,Indian Ocean,and South China Sea;15°S–60°N,39°–178°E)is a core strategic area for the‘21st Century Maritime Silk Road’project,as well as national ... The‘Two Oceans and One Sea’area(West Pacific,Indian Ocean,and South China Sea;15°S–60°N,39°–178°E)is a core strategic area for the‘21st Century Maritime Silk Road’project,as well as national defense.With the increasing demand for disaster prevention and mitigation,the importance of 10–30-day extended range prediction,between the conventional short-term(around seven days)and the climate scale(longer than one month),is apparent.However,marine extended range prediction is still a‘blank point’in China,making the early warning of marine disasters almost impossible.Here,the authors introduce a recently launched Chinese national project on a numerical forecasting system for extended range prediction in the‘Two Oceans and One Sea’area based on a regional ultra-high resolution multi-layer coupled model,including the scientific aims,technical scheme,innovation,and expected achievements.The completion of this prediction system is of considerable significance for the economic development and national security of China. 展开更多
关键词 Numerical prediction system ultra-high resolution multi-layer coupled model extended range prediction
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Observed Suspended Sediment Dynamics during a Tidal Cycle above Submerged Asymmetric Compound Sand Waves
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作者 Ingo Hennings Dagmar Herbers 《Journal of Environmental Science and Engineering(A)》 2016年第7期333-355,共23页
The data from Acoustic Doppler Current Profiler (ADCP) of the three-dimensional current-field, echo intensity, modulation of Suspended Sediment Concentration (SSC), and related water levels and wind velocities hav... The data from Acoustic Doppler Current Profiler (ADCP) of the three-dimensional current-field, echo intensity, modulation of Suspended Sediment Concentration (SSC), and related water levels and wind velocities have been analyzed as a function of water depth above submerged asymmetric compound sand waves during a tidal cycle in the Lister Tiefofthe German Bight in the North Sea. Signatures of vertical current component, echo intensities and calculated SSC modulations in the water column depend strongly on wind and current velocity. Bursts of vertical current component and echo intensity are triggered by sand waves itself as well as by superimposed megaripples due to current wave interaction at high current ≥ 1.0 m's1 and wind speeds ≥ 10.0 m·s^-1, preferably of opposite directions, measured at high spatial resolution. The magnitude of currents and SSC modulations during ebb and flood tidal current phases are only weakly time dependent, whereas the local magnitudes of these parameters are variable in space above the sand waves. Some hydrodynamic parameters are further investigated and analyzed, showing a consistence of ADCP measurements in the applied theory. 展开更多
关键词 Acoustic Doppler Current Profiler suspended sediment concentration asymmetric compound sand wave dynamic buoyancy density action density.
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Long-Term Evolution of the Black Sea Dynamics Derived from Modeling
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作者 Viktor Dorofeyev Larisa Sukhikh 《Journal of Shipping and Ocean Engineering》 2017年第1期35-42,共8页
Long-term evolution of the Black Sea dynamics (1980-2020) is reconstructed by means of numerical simulation. The model of the Black Sea circulation is z-coordinate model with 4.8 km horizontal space resolution and 4... Long-term evolution of the Black Sea dynamics (1980-2020) is reconstructed by means of numerical simulation. The model of the Black Sea circulation is z-coordinate model with 4.8 km horizontal space resolution and 40 levels in vertical direction. Mixing processes in the upper layer are parameterized with the Mellor-Yamada turbulent model. As for the boundary conditions on the sea surface, we used atmospheric forcing functions for the Black Sea region provided by CMCC using regional climate model COSMO-CLM. These data have a spatial resolution of 14km and a daily temporal resolution. To evaluate the quality of the Black Sea circulation dynamics, derived from simulation, the modeling results are compared with results of the Black Sea physical reanalysis. This reanalysis was performed by assimilating the temperature and salinity profiles from hydrographic surveys conducted during 1971-1993. 展开更多
关键词 Numerical modeling the Black Sea ocean currents seasonal variation.
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Experimental observation of fine secular frequency resonance oscillation with a rectilinear ion trap mass spectrometer
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作者 Lixin Shan Zuojian Zhang +4 位作者 Zhiyang Wei Yongze Gao Zhiyuan Luo Shiyu Cheng Jinian Shu 《Chinese Journal of Chemical Physics》 2024年第6期792-796,I0042,共6页
The mass resolution of the ordinary ion trap mass spectrometer derived from the quadrupole mass spectrometer usually ranges from hundreds to thousands.In this study,the fine secular frequency resonance oscillation was... The mass resolution of the ordinary ion trap mass spectrometer derived from the quadrupole mass spectrometer usually ranges from hundreds to thousands.In this study,the fine secular frequency resonance oscillation was observed with a rectilinear ion trap mass spectrometer.The FWHM of the responding resonance secular frequency of benzene was 0.012 kHz.The corresponding mass resolution was 8600 m/Δm for benzene(m/z=78).The mass spectrometer with secular frequency scanning has a linear response to benzene in the concentration range from 200 ppbv to 10000 ppbv.This study shows a new feature of the secular frequency scanning for ion trap mass spectrometers. 展开更多
关键词 Fine secular frequency Resonance oscillation Mass resolution Rectilinear ion trap mass spectrometer
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张晓春教授治疗乳腺癌经验 被引量:3
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作者 郭芸婷 戴小军 何正飞 《中医学报》 CAS 2015年第4期468-469,共2页
张晓春教授认为乳腺癌的病机主要为"心失神明,肝失疏泄",因而以"疏肝解郁,养心安神"为治疗大法,辨证与"辨期"相结合,扶正、祛邪因人制宜。遣方用药习惯于攻补兼施,以平消平补为主,慎用滋腻之品,主张于补... 张晓春教授认为乳腺癌的病机主要为"心失神明,肝失疏泄",因而以"疏肝解郁,养心安神"为治疗大法,辨证与"辨期"相结合,扶正、祛邪因人制宜。遣方用药习惯于攻补兼施,以平消平补为主,慎用滋腻之品,主张于补益药中配伍理气之品,使补而不滞,防止留邪之弊。同时根据患者具体情况,制定合理的综合治疗方案,并以全面功能康复为目标,结合食疗、针灸、药物、气功等中医特色康复疗法,树立患者战胜疾病的信心。 展开更多
关键词 乳腺癌 疏肝解郁法 养心安神法 “辨期” 张晓春
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Combined Acupuncture-moxibustion and Psychotherapy for Perimenopause Syndrome 被引量:1
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作者 刘登红 洪珏 《Journal of Acupuncture and Tuina Science》 2011年第5期283-286,共4页
Objective: To observe the effect of combined acupuncture-moxibustion with psychotherapy in treating perimenopause syndrome. Methods: Eighty patients with perimenopause syndrome were randomized into two groups. Forty... Objective: To observe the effect of combined acupuncture-moxibustion with psychotherapy in treating perimenopause syndrome. Methods: Eighty patients with perimenopause syndrome were randomized into two groups. Forty-two patients in the treatment group were intervened by acupuncture-moxibustion and psychotherapy, and the other 38 in the control group were treated by acupuncture-moxibustion only. The treatment was given once a day, 15 times constitute a treatment course. The therapeutic effects were evaluated after 3 treatment courses. Results: The total effective rate and the effective rate of the emotional state were both 97.6% in the treatment group, versus 89.5% and 73.7% in the control. The comparison of the total effective rate and the effective rate of the emotional state between the two groups both showed significant difference (P〈0.05). Conclusion: Acupuncture-moxibusiton has better effect in treating perimenopause syndrome when combined with psychotherapy. 展开更多
关键词 Acupuncture-moxibustion Therapy PSYCHOTHERAPY Perimenopause Syndrome Climacteric Syndrome Syndrome Differentiation Treatment
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Palaeo-sea-ice changes on the North Icelandic shelf during the last millennium:Evidence from diatom records 被引量:3
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作者 SHA LongBin JIANG Hui +4 位作者 LIU YanGuang ZHAO MeiXun LI DongLing CHEN ZhenLou ZHAO Yun 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第6期962-970,共9页
A high resolution record of sea-ice concentration on the North Icelandic shelf during the last millennium has been reconstructed using a diatom-based sea-ice transfer function. The reconstructed sea-ice record for the... A high resolution record of sea-ice concentration on the North Icelandic shelf during the last millennium has been reconstructed using a diatom-based sea-ice transfer function. The reconstructed sea-ice record for the top of sediment core MD99–2275 exhibits a slightly increasing trend over the last 1000 years. Prior to AD 1300 sea-ice abundance was generally below the mean value, suggesting the strong influence of warm waters from the Irminger Current during the Medieval Warm Period. A marked increase of sea-ice concentration indicates an abrupt change to colder conditions after AD 1300, corresponding to the onset of the Little Ice Age. The agreement between the reconstructed sea-ice concentration and IP25 data obtained from the same core, as well as with historical records of Icelandic sea ice, suggests that diatoms may provide a valuable tool for future quantitative reconstructions of past sea-ice variability. In addition, agreement between changes in the reconstructed sea-ice record and variations in the abundance of the major diatom components indicates that sea-ice conditions on the North Icelandic shelf are generally strongly influenced by changes in the strength of two different water masses, the cold Polar water periodically derived from the East Greenland Current and the warm Irminger Current derived from the North Atlantic Current. Our proxy evidence also indicates that variations in solar activity have a considerable impact on ocean dynamics, which in turn affects sea-ice abundance. 展开更多
关键词 palaeo-sea-ice changes North Icelandic shelf Medieval Warm Period Little Ice Age
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General characteristics of climate changes during the past 2000 years in China 被引量:15
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作者 GE QuanSheng ZHENG JingYun +1 位作者 HAO ZhiXin LIU HaoLong 《Science China Earth Sciences》 SCIE EI CAS 2013年第2期321-329,共9页
The general characteristics of climate changes over the past 2000 years in China,regional differences and uncertainties were analyzed based on the recently peer-reviewed high time-resolution climatic reconstructions.T... The general characteristics of climate changes over the past 2000 years in China,regional differences and uncertainties were analyzed based on the recently peer-reviewed high time-resolution climatic reconstructions.The results showed that there exists four warm periods of the temperature variation in China since the Qin Dynasty,including the western and eastern Han Dynasties(200 BC-AD 180),the Sui and Tang dynasties(541-810),the Song and Yuan dynasties(931-1320),and the 20th century,and three cold phases involving the Wei,Jin,and North-South Dynasties(181-540),the late Tang Dynasty(811-930),and the Ming and Qing dynasties(1321-1920).The Song and Yuan warm period is consistent with the Medieval Warm Period over the Northern Hemisphere,and the cold phases of the North-South Dynasties and the Ming and Qing dynasties are paralleled to the Dark Ages Cold Period and the Little Ice Age,respectively.The 13th-15th century could be a shift to the wet condition of the climate,and the low precipitation variability is exhibited in western China prior to 1500.In the context of the climate warming,the pattern of the drought in north and flood in south is prevalent over the eastern China.In addition,the published reconstructions have a high level of confidence for the past 500 years,but large uncertainties exist prior to the 16th century. 展开更多
关键词 past 2000 years temperature(cold/warm) precipitation(wet/dry) UNCERTAINTIES
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