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Investigation of Light-harvest Material:Synthesis and Characterization of Nanometer Porphyrin Trimer 被引量:1
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作者 SHIYing-yan WANGXing-qiao +4 位作者 LIXiang-qing ZHENGWen-qi dinghong ZHUGuang-shan LIUGuo-fa 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第3期262-265,共4页
ω -Bromopropylporphyrin ether synthesized from the raction of 1,3-dibromopropane as the bridge-linked reagent and 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin (H_2MHTPP) as the matrix reacts with 5,15-di(4- hydrox... ω -Bromopropylporphyrin ether synthesized from the raction of 1,3-dibromopropane as the bridge-linked reagent and 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin (H_2MHTPP) as the matrix reacts with 5,15-di(4- hydroxyphenyl)-10,20-diphenyl porphyrin( trans -H_2DHDPP) to give the title nanometer porphyrin trimer. The characterization was carried out by means of elemental analyses,UV-Vis,IR, 1H NMR and XRD. 展开更多
关键词 Nanometer porphyrin trimer ω -Bromopropylporphyrin ether Bridge-linking reagent
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Measurement of Similarity for Spatial Directions Between Areal Objects
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作者 dinghong GUOQingsheng DUXiaochu 《Geo-Spatial Information Science》 2004年第3期225-230,共6页
Similarity for spatial directions plays an important role in GIS. In this paper, the conventional approaches are analyzed. Based on raster data areal objects, the authors propose two new methods for measuring similari... Similarity for spatial directions plays an important role in GIS. In this paper, the conventional approaches are analyzed. Based on raster data areal objects, the authors propose two new methods for measuring similarity among spatial directions. One is to measure the similarity among spatial directions based on the features of raster data and the changes of distances between spatial objects, the other is to measure the similarity among spatial directions according to the variation of each raster cell centroid angle. The two methods overcome the complexity of measuring similarity among spatial directions with direction matrix model and solve the limitation of small changes in direction. The two methods are simple and have broader applicability. 展开更多
关键词 spatial similarity raster data similarity for spatial directions directionrelations' matrix map generalization
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Denitrification Losses and N_(2)O Emissions from Different Nitrogen Fertilizers Applied to the Maize-Fluvo-Aquic Soil System
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作者 dinghong WANGYue-si LIWei-hua 《Agricultural Sciences in China》 CAS CSCD 2005年第5期382-388,共7页
A field experiment was conducted to investigate the variations in denitrification losses and N2O emissions from 4 different types of nitrogen fertilizers (urea, ammonium nitrate, ammonium bicarbonate, and calcium nitr... A field experiment was conducted to investigate the variations in denitrification losses and N2O emissions from 4 different types of nitrogen fertilizers (urea, ammonium nitrate, ammonium bicarbonate, and calcium nitrate) applied to the maize- fluvo-aquic soil system in the North China Plain by the method of intact soil core incubation and acetylene inhibition, and the responses of nitrogen fertilizers to maize grain yields. Results show that the denitrification loss from different nitrogen fertilizers ranged from 0.38-1.20 kg N ha-1, with no significant differences among different fertilizer treatments, and the N2O emission from 0.05-0.95 kg N ha-1, with a significant difference (P<0.05) among the treatments. The highest emission was from the treatment of ammonium nitrate, while the lowest from calcium nitrate. The nitrogen fertilizers increased the maize grain yield by 9.7-19.8% compared to control. But there were no significant differences in yield increase among the 4 types of nitrogen fertilizers. In comparison, urea had the best effect, whereas calcium nitrate had the least effect on increasing maize yield. The maize yield was 5.7% higher when urea was separately applied at 2 times than when it was applied at a time. In this case, however, the denitrification loss and the N2O emission were also increased by 4.05 and 1.84 kg N ha-1, respectively. 展开更多
关键词 Nitrogen fertilizer DENITRIFICATION Nitrous oxide MAIZE Grain yield
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Hydrothermal Synthesis and Crystal Structure of a Highly Reduced Mixed Molybdenum-vanadium Polyoxometalate with Phosphorus-centered [Ni(phen)_3]_2H_2· [PMo_4~ⅤMo_4~ⅥV_6~ⅣM_2M_(44)]^(5-)·4H_2O(M=0.78Mo~Ⅴ+0.22V~Ⅳ)
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作者 SUNYing-hua dinghong +2 位作者 XUJi-qing LIYong LIGuang-hua 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第3期368-371,共4页
关键词 Hydrothermal synthesis POLYOXOMETALATE Crystal structure Transition metal
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九龙江流域丰水期表层沉积物还原性无机硫分布特征及其水库驱动机制
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作者 李松 余居华 +5 位作者 王丽 王煌平 郑祥洲 王利民 丁洪 张玉树 《环境科学学报》 CAS CSCD 北大核心 2023年第11期125-133,共9页
还原性无机硫(Reduced inorganic sulfur,RIS)是沉积物硫最活跃的组分,对水生态系统铁、磷以及重金属等元素的地球化学循环具有控制作用,目前氧化还原环境梯度变化明显的筑坝河流沉积物硫分布格局及其机理研究仍很缺乏.结合野外原位采... 还原性无机硫(Reduced inorganic sulfur,RIS)是沉积物硫最活跃的组分,对水生态系统铁、磷以及重金属等元素的地球化学循环具有控制作用,目前氧化还原环境梯度变化明显的筑坝河流沉积物硫分布格局及其机理研究仍很缺乏.结合野外原位采样和室内连续分级提取,在九龙江流域梯级水库作用下,探究表层沉积物RIS赋存形态、含量及其空间分布格局.结果表明:九龙江表层沉积物RIS各组分含量从高到低排序为:黄铁矿硫(Pyrite-S)>酸可挥发性硫化物(AVS)>单质硫(ES),其中以Pyrite-S为主要赋存形态,在RIS中的占比为83%~90%.九龙江流域不同类型水体沉积物RIS含量大小顺序为:水库>支流>干流,其中北溪、西溪表层沉积物RIS分布与水库的空间布局高度匹配,大致呈现水库斑块化热点分布,而南溪沉积物RIS沿水流方向从上游至下游却呈逐渐增加趋势,表明梯级水库的拦截效应增强了RIS在水库沉积物的累积强度.该结果增强了水库建设运行在流域尺度上对表层沉积物硫生物地化循环的影响认识,对九龙江流域的水环境保护与管理策略具有重要的理论和现实意义. 展开更多
关键词 沉积物 还原性无机硫 赋存形态 丰水期 水库 九龙江
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