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Photosynthetically active radiation retrieval based on HJ-1A/B satellite data

Science china Earth Sciences 2010年第S1期53卷 81-91页

作者： LI Li1,XIN XiaoZhou1,SU GaoLi1,2 & LIU QinHuo1 1 State Key laboratory of Remote Sensing Science,Institute of Remote Sensing Applications,Chinese Academy of Sciences,Beijing 100101,china 2 Zhejiang Climate Center,Hangzhou 310017,china State Key laboratory of Remote Sensing Science Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing China Zhejiang Climate Center Hangzhou China

Photosynthetically active radiation(PAR) is essential for plant photosynthesis and carbon cycle,and is also important for meteorological and environmental *** advance china's disaster and environmental monitoring capabilities,the HJ-1A/B satellites have been placed in Earth *** of their environmental monitoring objectives is the study of *** simulated direct solar,scattered and environment radiation between 400 and 700 nm under different atmospheric parameters(solar zenith angle,atmospheric water vapor,atmospheric ozone,aerosol optical thickness,surface elevation and surface albedo),and then established a look-up table between these input parameters and *** on the look-up table,we used HJ-1A/B aerosol and surface albedo outputs to derive the corresponding *** of inversed instantaneous and observed PAR values using HJ-1 Heihe experimental data had a root mean square error of 25.2 W m-2,with a relative error of 5.9%.The root mean square error for accumulated daily PAR and observed values was 0.49 MJ m-2,with a relative error of 3.5%.Our approach improved significantly the computational efficiency,compared with using directly radiation transfer *** also studied the sensitivity of various input parameters to photosynthetically active radiation,and found that solar zenith angle and atmospheric aerosols were sensitive PAR *** albedo had some effect on PAR,but water vapor and ozone had minimal impact on PAR.

关键词： Photosynthetically active radiation 6S HJ-1A/B satellites

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二甲醚选择性催化还原NO_x的试验研究

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上海交通大学学报 2010年第10期44卷 1347-1351页

作者：闫应张武高陈晓玲刘佳上海交通大学动力机械与工程教育部重点实验室上海200240

使用7%MoO3/γ-Al2O3（质量分数）为催化剂,对二甲醚（DME）作为还原剂选择性催化还原（SCR）降低NOx进行了试验研究.分别考察了反应温度、氧含量、DME与NO的比例对NO转化率的影响,测定了产物中的碳分布,并对NO与NO2分别作为NOx源进行... 详细信息

使用7%MoO3/γ-Al2O3（质量分数）为催化剂,对二甲醚（DME）作为还原剂选择性催化还原（SCR）降低NOx进行了试验研究.分别考察了反应温度、氧含量、DME与NO的比例对NO转化率的影响,测定了产物中的碳分布,并对NO与NO2分别作为NOx源进行了转化率比较.研究结果表明：常压条件下,在250～500℃内,随着反应温度的升高,NOx转化率先增大后减小;醚氮比对NO转化率的影响不明显;随着氧含量的增加,NOx转化率先增大后减小,当φO2=5%时,NO最高转化率约为53%;NO2比NO更容易被DME催化还原;含碳主要产物为CO、CO2,有少量甲醇（CH3OH）、甲醛（H2CO）生成.

关键词：二甲醚转化率选择性催化还原

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The relationship between spatial extent and duration of severe droughts in china over the last 50 years

The relationship between spatial extent and duration of seve...

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2010 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2010)

作者： ZHANG Da-quan College of atmospheric Sciences Lanzhou University Lanzhou china 730000FENG Guo-lin laboratory for Climate Studies National Climate Center china meteorological Administration Beijing china 100081

Correlation between spatial extent and duration of severe droughts process and its statistical law is analyzed using Palmer Drought Severity Index （PDSI） through a newly developed system of drought process monitoring. Results indicate that during the period from late 1990s to early 2000s,the percentage of severe drought （PDSI＜-3.0） in china is unprecedented since 1960 under the background of global warming and the variation of the distributions of droughts coverage areas in different seasons is uneven. The distribution of spatial extent and durations of severe droughts follows a power-law,e.g. the spatial-temporal characteristics of severe droughts is independent to their scaling,namely,being scale free. In general the area of severe droughts is correlated closely with its duration,while the deviations of the linear fit from its correlation is also high.

关键词： drought duration distribution power-law

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丙糖磷酸异构酶、果糖-1,6-二磷酸醛缩酶及果糖-1,6-二磷酸酶的共表达

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生物化学与生物物理学报 2001年第1期33卷 131-136页

作者：唐功利杨春松鲍建绍王燕芳陈海宝施定基刘凤龙中国科学院上海有机化学研究所生命有机化学国家重点实验室!上海20003.

致力于建立一条控制或降低大气中CO2 浓度的途径 ,选择对蓝藻进行代谢工程以便改进其光合固定CO2的效率。作为研究的初始阶段 ,将编码丙糖磷酸异构酶、果糖 1,6 二磷酸醛缩酶及果糖 1,6 二磷酸酶的 3个基因构建进一个由启动子trc控制的... 详细信息

致力于建立一条控制或降低大气中CO2 浓度的途径 ,选择对蓝藻进行代谢工程以便改进其光合固定CO2的效率。作为研究的初始阶段 ,将编码丙糖磷酸异构酶、果糖 1,6 二磷酸醛缩酶及果糖 1,6 二磷酸酶的 3个基因构建进一个由启动子trc控制的表达质粒 pTrcFAT ,成功地在大肠杆菌中实现了上述 3个基因的活性共表达。活性测定结果显示 :从 1L培养液获得的破菌上清液每分钟可以催化二羟丙酮磷酸 (DHAP)转化成 70 0 μmol果糖 6 磷酸。在此基础上进一步构建了这 3个基因共表达的大肠杆菌蓝藻穿梭表达质粒 ,也在大肠杆菌中实现了活性表达。当外源基因的操纵子与载体质粒以大于 1∶1的比例进行构建时 ,可显著提高外源基因的表达量及相应的酶活性

关键词：丙糖磷酸异构酶果糖-1,6-二磷酸醛缩酶果糖-1,6-二磷酸酶共表达

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The　concentration　and　distribution　of　dimethyl　sulfide　in　the　marine　atmospheric　boundary　layer　near　the　equator

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Acta Oceanologica Sinica 1995年第3期14卷 355-369页

作者： Li Xingsheng Li Zhe F. Parungo and C. Nagamoto ( Chinese Academy of meteorological Science, State meteorological Administration, Beijing, china)(NOAA/ERL, Air Resources laboratory, Boulder, CO 80303, U. S. A.)

A one-dimensional photochemical model with parameterized vertical eddy diffusion is used to simulate the dimethyl sulfide (DMS) in the marine atmospheric boundary layer near the equator. The boundary condition of theDMS flux over sea surface is assigned from gas exchange models that deped on sea surface wind speed and DMS concentration in surface water. Photolysis rates at various altitudes are calculated as a function of Solar zenith angle, andthe radiation calculation includes ozone absorption,surface reflection and molecular *** simulated results of the DMS diurnal cycle are in good agreement with the observations. Sensitivity tests ofthe model indicate that the concentration of the DMS in the marine surface layer appears to be affected by a combination of chemical processes and meteorological conditions. In addition, photochemical processes are rather *** reaction of the DMS with OH radical, the heterogeneous conversion of SO2 and the deposition of NSS-SO andthe methanesulfonic acid (MSA) are critical factors of controlling the DMS, SO2, NSS-SO and the MSA concentrations and distributions in the *** DMS concentration in air is directly proportional to surface windspeed, but it is inversely proportional to boundary layer height in the convective boundary layer. The distributions ofthe DMS concentrations in air are strongly influenced by atmospheric stratification in stable conditions.

关键词： Dimethyl sulfide marine atmospheric boundary layer equator

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WMO TYPHOON LANDFALL FORECAST DEMONSTRATION PROJECT(WMO-TLFDP) PROGRESS AND FUTURE PLANS

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Tropical Cyclone Research and Review 2016年第3期5卷 72-84页

作者： Xiaotu Lei Hui Yu Guomin Chen Barbara Brown Sai Tick Chan Ajit Tyagi shanghai Typhoon Institute National Center for atmospheric Research Hongkong Observatory Indian meteorological Society shanghai Typhoon Institute National Center for atmospheric Research Hongkong Observatory Indian meteorological Society

The "WMO Typhoon Landfall Forecast Demonstration Project(TLFDP)" was started in May 2010 in conjunction with the start of the shanghai World Expo 2010. The project was successful in terms of assisting the local forecasters in providing an efficient tropical cyclone(TC) forecast service for World Expo 2010, demonstrating the performance of the most up-to-date techniques in TC forecasting, and enhancing the ability of forecasters to effectively use products based on advanced TC forecasting techniques. The first phase was completed in December 2012 and the second phase was completed in December 2015. The third phase(TLFDP-III) started in *** its first(2010-2012) and second(2013-2015) phases, TLFDP collected real-time TC forecast products from 15 Typhoon Forecast Product Providers(TFPPs). The products include deterministic track and intensity forecasts, ensemble track and intensity forecasts, deterministic wind radii forecasts, wind probability forecasts, and gridded model outputs. The products were disseminated through the project's website and the operational website of the shanghai Typhoon Warning *** has made significant progress in TC forecast verification, including setting up the tools for both realtime and post-season TC forecast verification, developing and integrating several new verification techniques, carrying out a survey on the operational status of TC forecast verification in the western North Pacific region, and contributing to the WMO document "Verification of tropical cyclone forecasts". The post-season forecast verification was reported to the Session of the UNESCAP/WMO Typhoon Committee since 2013. New consensus methods for TC track and intensity forecasts were also proposed either based on Ensemble Prediction Systems(EPSs) products or multiple deterministic NWP model products. Two training workshops on TC forecasting were organized by the TLFDP and held in shanghai, china, in May 2010 and June 2012, respectively, and seven research

关键词： WMO Forecast Demonstration Project typhoon landfall evaluation and assessment

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Lightning activity and precipitation structure of hailstorms

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Science china Earth Sciences 2007年第4期50卷 629-639页

作者： FENG GuiLi1,2, QIE XiuShu3,1, YUAN Tie1 & NIU ShuZhen4 1 laboratory of Lightning and Thunderstorm, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, china 2 Shandong Research Institute of Meteorology, Jinan 250031, china 3 Institute of atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 4 The meteorological Observatory of Henan Province, Zhengzhou 450003, china laboratory of Lightning and Thunderstorm Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China Shandong Research Institute of Meteorology Jinan 250031China Institute of atmospheric PhySics Chinese Academy of SciencesBeijing 100029China laboratory of Lightning and Thunderstorm Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China laboratory of Lightning and Thunderstorm Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China The meteorological Observatory of Henan Province Zhengzhou 450003China

By using the cloud-to-ground (CG) lightning location data from the lightning detection network of He- nan Province, surface Doppler radar data and standard orbit data of PR, TMI and LIS on TRMM satellite, the spatial and temporal characteristics of CG lightning flashes in 10 severe hailstorms are analyzed. The results show that the percentage of +CG lightning in these hailstorms is high with an average value of 45.5%. There is a distinct increase in CG flash rate during the rapid development stage of hailstorms. The hailstone falling corresponds to an active positive flash period, and the increase of +CG flash rate is generally accompanied with a decrease of –CG flash rate. The flash rate declines rapidly during the dissipating stage of hailstorms. The precipitation structure and lightning activity in two typical hail- storms are studied in detail. It is found that strong convective cells with reflectivity greater than 30dBZ mainly are situated in the front region of hailstorms, whereas the trailing stratiform region is in the rear part of the hailstorms. The maximum heights of echo top are higher than 14 km. Convective rain con- tributes much more rainfall to the total than stratiform rain, and the convective rain takes about 85% and 97% of the total in the two cases, respectively. Total lightning in the hailstorms is very active with the flash rate up to 183 fl/min and 55 fl/min, respectively. The results also indicate that most lightning flashes occurred in the echo region greater than 30 dBZ and its immediate periphery. The probability of lightning occurrence is 20 times higher in the convective region than in the stratiform region. The result suggests that the lightning information is helpful to the identification of convective rain region. The linear relationship between flash rate and ice water content is disclosed primarily.

关键词： total lightning activity positive CG lightning hailstorm convective rain ice water content

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Pilot study on polychlorinated dibenzo-p-dioxins and dibenzofurans level of agricultural soil in shanghai,china

Pilot study on polychlorinated dibenzo-p-dioxins and dibenzo...

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持久性有机污染物论坛2009暨第四届持久性有机污染物全国学术研讨会

作者： Rong Zhiyi,Li Kang,Yin Haowen Bioassay and Safety laboratory,shanghai Academy of Public Measurement,shanghai,200233

*** Along with the growing awareness and concerns of food safety,the nature of agricultural field and its pollution status is now becoming an important issue to both the government and the public in *** polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs) adhere strongly to the organic substance in soil and act as passive collectors for atmospheric deposition,soil has been regarded as a suitable medium to evaluate dioxin pollution over a long *** its potential toxicity to the human

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NAA of organohalogens in air particles and precipitation in shanghai

NAA of organohalogens in air particles and precipitation in ...

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The 1st Asian-Pacific Symposium on Radiation chemistry

作者： Xinnian LI Tailiu YU Junpeng GUO Youyou XIONG Wenyun LUO shanghai Institute of Radiation Applications shanghai University shanghai 201800 china

Organohalogens are ubiquitous pollutants which are especially controlled in many countries and their behaviors in environment become the hot topic in environment science. By the method of neutron activation analysis （NAA） combined with chemical separation, the extractable organohalogens （EOX） in environmental samples were determined. NAA is a nuclear analysis method, which has high sensibility and high precision. The detection limits were 50ng, 8ng, 3.5ng for Cl, Br, I, respectively. The principle is that when the sample was irradiated by thermal neutron, the energies and the intensities of γ ray of halogen nuclides（38Cl, Eγ=1642keV, t1/2=37.24min;80Br,Eγ=617keV, t1/2=17.68min;128I, Eγ=443keV, t1/2=24.99min）produced by nuclear reaction can be measured. Total content of halogens were analyzed and the organochlorines, organobromines and organoiodines in the samples were detected.

关键词： atmospheric environment Neutron activition analysis Organohalogens

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Dimethyl sulfide in the atmospheric surface layer of the Equatorial Pacific Ocean

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Acta Oceanologica Sinica 1993年第1期12卷 79-91页

作者： Li Xingsheng F. Parungo, C. Nagamoto and S. Hoyt Chinese Academy of meteorological Sciences, State meteorological Administration, Beijing 100081 , china Air Resources laboratory, NOAA/ERL, Boulder, Colorado, U. S. A. Environmental Analytical Service, San Luis Obispo, California, U. S. A. Chinese Academy of meteorological Sciences State Meteorological Administration Beijing 100081 China China

This paper reports a case study of atmospheric stability effect on dimethyl sulfide(DMS) concentration in the air. Investigation includes model simulation and field measurements over the Pacific Ocean. DMS concentration in surface sea water and in the air were measured during a research cruise from Hawaii to Tahiti. The diurnal variation of air temperature over the sea surface differed from the diurnal cycle of sea surface temperature because of the high heat capacity of sea water. The diurnal cycle of average DMS concentration in the air was studied in relation to the atmospheric stability parameter and surface heat flux. All these parameters had minima at noon and maxima in the early morning. The correlation coefficient of the air DMS concentration with wind speed (at 15 m high) was 0. 64. The observed concentrations of DMS in the equatorial marine surface layer and their diurnal variability agree well with model simulations. The simulated results indicate that the amplitude of the cycle and the mean concentration of DMS are dependent on the atmospheric stratifications and wind speed.

关键词： DMS Dimethyl sulfide in the atmospheric surface layer of the Equatorial Pacific Ocean

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