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应用文献计量学的方法,对2006~2007年及1999~2008年每年的第1期,共20期《南昌大学学报(理科版)》进行定量分析,并与相关的文献报道进行比较。分析结果表明:该刊在相近的同类高校学报(科技期刊)中,载文量较高,基金项目论文平均达到65.95%;论文合著率为88.26%,合作度为2.89;第一  相似文献   
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In mid-September 2013, PM2.5 samples were collected at six sites in Nanchang, Jiangxi Province, China, to quantify nine water-soluble ions (Ca2+, Mg2+, K+, Na+, NH4+, SO42−, Cl, F, NO3), 29 trace elements (Ba, Zn, Pb, Ni, Mo, Cr, Cu, Sr, Sb, Rb, Cd, Bi, Zr, V, Ga, Li, Y, Nb, W, Cs, Tl, Sc, Co, U, Hf, In, Re, Be, and Ta), and to characterize Pb isotopic ratios (207Pb/206Pb, 208Pb/206Pb, and 207Pb/204Pb) for identifying the main source(s) of Pb. The results showed that the average daily PM2.5 concentration (53.16 ± 24.17) μg/m3 was within the secondary level of the Chinese ambient air quality standard. The combined concentrations of SO42−, NH4+, and NO3 to total measured water-soluble ion concentrations in PM2.5 ranged from 79.40% to 95.18%, indicating that anthropogenic sources were significant. Coal combustion and vehicle emissions were both contributors to PM2.5 based on the NO3/SO42− ratios. Wushu School experienced the lowest concentrations of PM2.5 and most trace elements among the six sampling sites. Enrichment factor results showed that Tl, Cr, In, Cu, Zn, Pb, Bi, Ni, Sb, and Cd in PM2.5 were affected by anthropogenic activities. Cluster analysis suggested that Cd, Sb, Pb, Re, Zn, Bi, Cs, Tl, Ga, and In were possibly related to coal combustion and vehicle exhaust, while Ni, Nb, Cr, and Mo may have originated from metal smelting. Pb isotopic tracing showed that coal dust, cement dust, road dust and construction dust were the major Pb sources in PM2.5 in Nanchang. Combined, these sources contributed an average of 72.51% of the Pb measured, while vehicle exhaust accounted for 27.49% of Pb based on results from a binary Pb isotope mixed model.  相似文献   
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应用地质累积指数评价南昌市城市污泥重金属污染   总被引:5,自引:0,他引:5  
应用地质累积指数对南昌市城市污泥(包括污水处理厂污泥和纸厂废水处理污泥)的重金属污染进行了分析评价。结果表明,城市污泥重金属中Pb、Cr按地质累积指数分级均为0,属无污染;As地质累积指数为0~1之间,表现为无污染~中度污染;青山湖污水处理厂污泥主要的重金属污染元素为Cd、Hg、Cu、Zn,其平均的地质累积指数为2~4,表现为中度污染~强污染。  相似文献   
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本文报导了南昌绿化树种的调查情况,论述了绿化与环境的相互关系,同时提出了今后绿化的建议,为南昌的绿化提供科学依据。  相似文献   
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A mild and convenient visible-light-promoted cross-dehydrogenative-coupling reaction between N-arylglycine esters and imidazo[1,2-a]pyridines for the construction of CC bond was developed. A range of N-arylglycine esters and imidazo[1,2-a]pyridines were able to undergo the CDC reaction readily to afford α-heteroaryl substituted α-amino acid derivatives in good to excellent yields. A tentative mechanism for the photoredox reaction was also proposed. Importantly, the use of copper(II) salt as the sole catalyst in this visible-light-promoted transformation makes this reaction sustainable and practical.  相似文献   
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A green and practical method for the synthesis of N-arylsulfonamides from chloramine salts and arylboronic acids is herein developed. The reaction proceeds readily in the presence of 5?mol% of CuI and 2.5?equiv. K2CO3 in water at room temperature, generating a variety of N-arylsulfonamides in moderate to good yields with good functional group tolerance.  相似文献   
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