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Chinese Physics B 2012年第10期21卷 614-621页

作者：钱忠华胡经国封国林曹永忠 College of Physical Science & Technology Yangzhou University National climate center

Based on the skewed function,the most probable temperature is defined and the spatiotemporal distributions of the frequencies and strengths of extreme temperature events in different climate states over China are investigated,where the climate states are referred to as State I,State II and State III,i.e.,the daily minimum temperature records of 1961-1990,1971-2000,and *** results show that in space the frequency of high temperature events in summer decreases clearly in the lower and middle reaches of the Yellow River in State I and that low temperature events decrease in northern China in State *** the present state,the frequency of high temperature events increases significantly in most areas over China except the north east,while the frequency of low temperature events decreases mainly in north China and the regions between the Yangtze River and the Yellow *** distributions of frequencies and strengths of extreme temperature events are consistent in *** analysis of time evolution of extreme events shows that the occurrence of high temperature events become higher with the change in state,while that of low temperature events *** temperature events are becoming stronger as well and deserve to be paid special attention.

关键词： extreme temperature most probable temperature climate state

SYNTHESIS AND CHARACTERIZATION OF POLY(p-ARYLENE SULFIDE KETONE/SCHIFF BASE) COPOLYMERS

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Chinese Journal of Polymer Science 2012年第3期30卷 370-377页

作者：杨杰 Analytical and Testing center Sichuan University State Key Laboratory of Polymer Materials & Engineering(sichuan University)

Poly（p-arylene sulfide ketone/Schiffbase） copolymers （PASK/SB） were prepared by solution polycondensation of 4,4＇-diflurobenzophenone （DFBP） and N-phenyl（4,4＇-diflurodiphenyl） ketimine （DFBI） with sodium sulfide in the presence of sodium hydroxide under normal pressure. Elemental analyses, FT-IR, NMR, DSC, TGA and XRD were used to characterize the resultant copolymers. It was found that the copolymers had good thermal properties with glass transition temperature （Tg） of 155.0-172.0℃, melting temperature （Tm） of 298-344℃, 5% weight loss temperatures （Td） of 471.0-501.5℃. These copolymers were almost amorphous with the content of DFBI beyond 30%. The polymer with 100% DFBI had excellent solubility, and it could dissolve in some solvents such as tetrahydrofuran （THF） and N-methyl-2- pyrrolidone （NMP）. The processability of polymers was improved. Meantime the viscosity of PASK made from hydrolysis of PASK/SB （H-PASK/SB） was greatly improved from 0.135 dL/g to 0.605 dL/g.

关键词： Synthesis PASK Schiffbase Copolymer Spin ability.

ENSO Features, Dynamics, and Teleconnections to East Asian climate as Simulated in CAMS-CSM

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Journal of Meteorological Research 2019年第1期33卷 46-65页

作者： Bo LU Hong-Li REN Laboratory for climate Studies & China Meteorological Administration–Nanjing University Joint Laboratory for climate Prediction Studies National Climate Center China Meteorological Administration Xinjiang climate center Department of Atmospheric Science School of Environmental Studies China University of Geoscience

This study evaluates the performance of CAMS-CSM(the climate system model of the Chinese Academy of Meteorological Sciences) in simulating the features, dynamics, and teleconnections to East Asian climate of the El Ni?o–Southern Oscillation(ENSO). In general, fundamental features of ENSO, such as its dominant patterns and phase-locking features, are reproduced well. The two types of El Ni?o are also represented, in terms of their spatial distributions and mutual independency. However, the skewed feature is missed in the model and the simulation of ENSO is extremely strong, which is found—based on Bjerknes index assessment—to be caused by underestimation of the shortwave damping effect. Besides, the modeled ENSO exhibits a regular oscillation with a period shorter than observed. By utilizing the Wyrtki index, it is suggested that this periodicity bias results from an overly quick phase transition induced by feedback from the thermocline and zonal advection. In addition to internal dynamics of ENSO,its external precursors—such as the North Pacific Oscillation with its accompanying seasonal footprinting mechanism, and the Indian Ocean Dipole with its 1-yr lead correlation with ENSO—are reproduced well by the model. Furthermore, with respect to the impacts of ENSO on the East Asian summer monsoon, although the anomalous Philippine anticyclone is reproduced in the post-El Ni?o summer, it exhibits an eastward shift compared with observation;and as a consequence, the observed flooding of the Yangtze River basin is poorly represented, with unrealistic air–sea interaction over the South China Sea being the likely physical origin of this bias. The response of wintertime lowertropospheric circulation to ENSO is simulated well, in spite of an underestimation of temperature anomalies in central China. This study highlights the dynamic processes that are key for the simulation of ENSO, which could shed some light on improving this model in the future.

关键词： model evaluation ENSO dynamics teleconnection CAMS-CSM

Changing Trends of Daily Temperature Extremes with Different Intensities in China

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Acta meteorologica Sinica 2012年第4期26卷 399-409页

作者：王遵娅丁一汇张强宋亚芳 National climate center China Meteorological Administration National climate center China Meteorological Administration China Meteorological Administration

By comparing two sets of quality-controlled daily temperature observation data with and without the inhomogeneity test and adjustment from 654 stations in China during 1956 2004 and 1956-2010, impacts of inhomogeneity on changing trends of four percentile temperature extreme indices, including occurrences of cold days, cold nights, warm days, and warm nights with varying intensities, were discussed. It is found that the inhomogeneity affected the long-term trends averaged over extensive regions limitedly. In order to minimize the inhomogeneity impact, the 83 stations identified with obvious inhomogeneity impacts were removed, and an updated analysis of changing trends of the four temperature extreme indices with varying intensities during 1956 2010 was conducted. The results show that annual occurrences of both cold nights and cold days decreased greatly while those of warm nights and warm days increased significantly during the recent 20 years. The more extreme the event is, the greater the magnitude of changing trends for the temperature extreme index is. An obvious increasing trend was observed in annual occurrences of cold days and cold nights in the recent four years. The magnitude of changing trends of warm extreme indices was greater than that of cold extreme indices, and it was greater in northern China than in southern China. Trends for summer occurrence of cold days were not significant. Decreasing trends of occurrences of both cold nights and cold days were the greatest in December, January, and February （DJF） but the least in June, July, and August （JJA）, while increasing trends of warm nights were the greatest in JJA. Cold nights significantly decreased from 1956 to 1990, and then the decreasing trend considerably weakened. The decreasing trend also showed an obvious slowdown in recent years for occurrence of cold days. However, increasing trends of warm nights and warm days both have been accelerated continuously since the recent decades. Further analy

关键词： temperature extremes cold nights cold days warm nights warm days changing trend

Arctic Sea Ice and Eurasian climate:A Review

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Advances in Atmospheric Sciences 2015年第1期32卷 92-114页

作者： GAO Yongqi SUN Jianqi LI Fei HE Shengping Stein SANDVEN YAN Qing ZHANG Zhongshi Katja LOHMANN Noel KEENLYSIDE Tore FUREVIK SUO Lingling Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Nansen Environmental and Remote Sensing center/Bjerknes center for climate Research climate Change Research center Chinese Academy of Sciences Uni Research/Bjerknes center for climate Research Max-Planck Institute for Meteorology Geophysical Institute University of Bergen/Bjerknes Center for Climate Research

The Arctic plays a fundamental role in the climate system and has shown significant climate change in recent decades,including the Arctic warming and decline of Arctic sea-ice extent and thickness. In contrast to the Arctic warming and reduction of Arctic sea ice, Europe, East Asia and North America have experienced anomalously cold conditions, with record snowfall during recent years. In this paper, we review current understanding of the sea-ice impacts on the Eurasian ***, observational and modelling studies are covered to summarize several major themes, including： the variability of Arctic sea ice and its controls; the likely causes and apparent impacts of the Arctic sea-ice decline during the satellite era,as well as past and projected future impacts and trends; the links and feedback mechanisms between the Arctic sea ice and the Arctic Oscillation/North Atlantic Oscillation, the recent Eurasian cooling, winter atmospheric circulation, summer precipitation in East Asia, spring snowfall over Eurasia, East Asian winter monsoon, and midlatitude extreme weather; and the remote climate response（e.g., atmospheric circulation, air temperature） to changes in Arctic sea ice. We conclude with a brief summary and suggestions for future research.

关键词： Arctic sea ice Eurasian climate Arctic Oscillation review

Changes in Regional Heavy Rainfall Events in China during 1961–2012

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Advances in Atmospheric Sciences 2015年第5期32卷 704-714页

作者： ZOU Xukai REN Fumin National climate center State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Jiangsu Collaborative Innovation center for climate Change

A new technique for identifying regional climate events, the Objective Identification Technique for Regional Extreme Events（OITREE）, was applied to investigate the characteristics of regional heavy rainfall events in China during the period1961–2012. In total, 373 regional heavy rainfall events（RHREs） were identified during the past 52 years. The East Asian summer monsoon（EASM） had an important influence on the annual variations of China＇s RHRE activities, with a significant relationship between the intensity of the RHREs and the intensity of the Mei-yu. Although the increase in the frequency of those RHREs was not significant, China experienced more severe and extreme regional rainfall events in the 1990 s. The middle and lower reaches of the Yangtze River and the northern part of South China were the regions in the country most susceptible to extreme precipitation events. Some stations showed significant increasing trends in the southern part of the middle and lower reaches of the Yangtze River and the northern part of South China, while parts of North China, regions between Guangxi and Guangdong, and northern sichuan showed decreasing trends in the accumulated intensity of *** spatial distribution of the linear trends of events＇ accumulated intensity displayed a similar so-called ＂southern flooding and northern drought＂ pattern over eastern China in recent decades.

关键词： China regional heavy rainfall events

Characterization of summer PM_(2.5) aerosols from four forest areas in sichuan,SW China

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Particuology 2015年第3期13卷 94-103页

作者： Hengqin Mo Li Li Wei Lai Min Zhao Jinguo Pu Yi Zhou Shihuai Deng Rural Environment Protection Engineering & Technology center of sichuan Province College of Resources and EnvironmentSichuan Agricultural University Meishan Environmental Monitoring center

Aerosol samples were collected over 24 and 12 h to represent day/night aerosol characteristics in forest areas at Ya＇an Baima Spring Scenic Area （BM）, Panzhihua Cycas National Nature Reserve （PZ）, Gongga Mountain National Nature Reserve （GG）, and Wolong National Nature Reserve （WL）, during the summers of 2010-2012. Mass and chemical component concentrations, including organic carbon, elemental car- bon, and inorganic ions （F , C1 , NO2-, NO3-, SO42-, C2042-, PO43-, K＋, Na＋, Ca2＋, Mg2＋, and NH4＋）, of PM2.5 aerosols were measured. The average PM2.5 concentrations for 24 h were 72.42, 104.89, 20.55, and 29.19 p,g/m3 at BM, PZ, GG, and WL, respectively. Organic matter accounted for 38.0-49.3%, while ele- mental carbon accounted for 2.0-5.7% of PM2.s mass. The sum concentrations of 5042-, NH4＋, and NO3- accounted for 23.0%, 17.4%, 22.1%, and 30.5% of PM2.s mass at BM, PZ, GG, and WL, respectively. Soil dust was also an important source of PM2.s, accounting for 6.3%, 17.0%, 10.4%, and 19.1% of PM2.s mass at BM, PZ, GG, and WL, respectively. These reconstructed masses accounted for 75.9-102.0% of PM2.5 mass from the four forest areas of SW China.

关键词： PM2.5Forest areasMass closureSouthwest China

COMPARISON OF DRUG DELIVERY PROPERTIES OF PEG-b-PDHPC MICELLES WITH DIFFERENT COMPOSITIONS

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Chinese Journal of Polymer Science 2012年第3期30卷 387-396页

作者：顾忠伟 National Engineering Research center for Biomaterials Sichuan University

An anti-tumor drug doxorubicin was encapsulated in micelles of poly（ethylene glycol）-b-poly（2,2-dihydroxyl- methyl propylene carbonate）（PEG-b-PDHPC） diblock copolymers. The morphololgy of both blank miceiles and drug loaded micelles was characterized by TEM. The in vitro drug release profiles of micelles were investigated, The cytotoxicity of the micelles was evaluated by incubating with Hela tumor cells and 3T3 fibroblasts. The drug loaded micelles were co-cultured with HepG2 cells to evaluate the in vitr9 anti-tumor efficacies. The results showed that the mean sizes of both micelles with different copolymer compositions increased after being loaded with drugs. The drug release rate of PEG45-b-PDHPC34 micelles was faster than that of mPEGt14-b-PDHPC26 micelles. Both of the two block copolymers were non-toxic. The confocal laser scanning microscopy a：ad flow cytometry results showed that both the drug loaded micelles could be internalized efficiently in HepG2 cells. The PEG45-b-PDHPC34 micelles exhibited higher anti-tumor activity comparing to mPEGxla-b-PDHPC26 micelles.

关键词： Drug delivery Micelles Doxorubicin Biodegradable.

Manipulation of multiple electromagnetically induced two-photon transparency in a six-level atomic system

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Chinese Physics B 2009年第6期18卷 2282-2287页

作者：贾文志王顺金 center of Theoretical Physics School of PhysicsSichuan University

In the five-level K-type atomic system, by using another control field to couple the excited level of the coupling transition to the sixth higher excited level, a six-level atomic system is constructed. In this system, the multiple electromagnetically induced two-photon transparency has been investigated. What is more, if choosing the parameters of the control fields properly the triple transparency window will reduce to a double one which means that the multiple electromagnetically induced two-photon transparency can be manipulated in this system. The physical interpretation of these phenomena is given in terms of the dressed states and the dark states.

关键词： electromagnetically induced transparency dressed states dark states

The 2022 Extreme Heatwave in Shanghai,Lower Reaches of the Yangtze River Valley:Combined Influences of Multiscale Variabilities

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Advances in Atmospheric Sciences 2024年第4期41卷 593-607页

作者： Ping LIANG Zhiqi ZHANG Yihui DING Zeng-Zhen HU Qi CHEN Key Laboratory of Cities’Mitigation and Adaptation to climate Change in Shanghai Shanghai Regional Climate CenterChina Meteorological AdministrationShanghai 200030China National climate center China Meteorological AdministrationBeijing 100081China climate Prediction center NCEP/NWS/NOAACollege ParkMD 20740USA

In the summer of 2022,China(especially the Yangtze River Valley,YRV)suffered its strongest heatwave(HW)event since *** this study,we examined the influences of multiscale variabilities on the 2022 extreme HW in the lower reaches of the YRV,focusing on the city of *** found that about 1/3 of the 2022 HW days in Shanghai can be attributed to the long-term warming trend of global *** mid-summer of 2022,an enhanced western Pacific subtropical high(WPSH)and anomalous double blockings over the Ural Mountains and Sea of Okhotsk,respectively,were associated with the persistently anomalous high pressure over the YRV,leading to the extreme *** Pacific Decadal Oscillation played a major role in the anomalous blocking pattern associated with the HW at the decadal time ***,the positive phase of the Atlantic Multidecadal Oscillation may have contributed to regulating the formation of the double-blocking *** warming of both the warm pool of the western Pacific and tropical North Atlantic at the interannual time scale may also have favored the persistency of the double blocking and the anomalously strong *** the subseasonal time scale,the anomalously frequent phases 2-5 of the canonical northward propagating variability of boreal summer intraseasonal oscillation associated with the anomalous propagation of a weak Madden-Julian Oscillation suppressed the convection over the YRV and also contributed to the ***,the 2022 extreme HW originated from multiscale forcing including both the climate warming trend and air-sea interaction at multiple time scales.

关键词： extreme heatwave multiscale variability air-sea interaction warming trend Yangtze River Valley Shanghai