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合福高速铁路江田特大桥主桥线形控制
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作者 吴世波 《城市道桥与防洪》 2012年第6期197-199,16-17,共3页
该文以合福高速铁路线上江田特大桥为背景,介绍大跨铁路连续梁悬臂浇筑施工工艺流程,以及连续梁悬臂浇筑线性控制的难点及措施。通过有限元仿真模型计算了连续梁各节段理论变形值,并进行了连续梁桥各结构参数的敏感性分析,找出了显著影... 该文以合福高速铁路线上江田特大桥为背景,介绍大跨铁路连续梁悬臂浇筑施工工艺流程,以及连续梁悬臂浇筑线性控制的难点及措施。通过有限元仿真模型计算了连续梁各节段理论变形值,并进行了连续梁桥各结构参数的敏感性分析,找出了显著影响连续梁桥线性变化的参数。成桥后表明:合拢段误差满足规范要求,主梁线形满足设计要求。 展开更多
关键词 高速铁路 连续梁 线形控制 江田特大桥
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日本学界动向——近10年来日本对辛亥革命的研究
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作者 武上真理子 《近代中国》 2011年第1期371-379,共9页
本文是对近年来日本辛亥革命研究动向的简单介绍。日本孙文研究会发行的学术期刊《孙文研究》的第48、49号合刊,曾刊登过日本京都大学教授江田宪治的论文《辛亥革命一百周年与近十年来日本对辛亥革命之研究》。该论文对过去10年来日本... 本文是对近年来日本辛亥革命研究动向的简单介绍。日本孙文研究会发行的学术期刊《孙文研究》的第48、49号合刊,曾刊登过日本京都大学教授江田宪治的论文《辛亥革命一百周年与近十年来日本对辛亥革命之研究》。该论文对过去10年来日本辛亥革命研究的动向进行了概括总结。附表《近十年来日本对辛亥革命之研究》是我在江田教授论文的基础上做成的一览表。 展开更多
关键词 动向 研究 教授 江田 日本 学术期刊
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人物志
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《财经》 2007年第17期15-15,共1页
沈跃跃:升职常务;马力:英年早逝;江田五月:新任仪长;梁伯韬:加盟PE;徐文艾:造纪被撤;胡星:无期徒刑.
关键词 人物志 沈跃跃 中央常务委员 马力 民主建港协进联盟主席 江田五月 新任仪长 梁伯韬 PE高级顾问
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Spatial Distribution and Changes of Heavy Metals of Agricultural Lands in Typical Pregrading Coast in Dongtai City,Jiangsu Province,China 被引量:4
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作者 LIAO Fuqiang ZHOU Shenglu +2 位作者 ZHANG Hongfu WU Shaohua ZHAO Qiguo 《Chinese Geographical Science》 SCIE CSCD 2008年第3期276-283,共8页
According to the historical changes of coastal lines, seven soil sampling districts, from land to sea, were arranged in Dongtai City, Jiangsu Province to sample soils from surface and profile. Concentrations of seven ... According to the historical changes of coastal lines, seven soil sampling districts, from land to sea, were arranged in Dongtai City, Jiangsu Province to sample soils from surface and profile. Concentrations of seven major heavy metals (HMs), granularity, pH, organic matters and C/N of the soil samples were analyzed. Results show that concentrations of heavy metals in agricultural land present a certain spatial variance, decreasing from land to sea. Pollution assessment indicates that the agricultural soils were not polluted by HMs, but the potential pollution of Cu and Hg needs to be alerted. Different HMs accumulate in the surface and sub-surface of the soil profiles, and concentrations of Hg and Pb decrease significantly with the increment of soil depth. Concentrations of HMs exhibit a significantly negative correlation to pH, but have no significant relation with organic matters in soil. Principle component analysis show that the concentrations of HMs relate to the land use history. Concentrations of Hg, Ni and Cr in soil are closely related with land use history, and concentrations of Pb, Cu and Cr are affected by land use history as well as other factors. However, there is no significant relation between concentration of As and land use history. 展开更多
关键词 coastal zone agriculture land heavy metal land use history
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Pollen and Phytolith Analyses of Ancient Paddy Fields at Chuodun Site, the Yangtze River Delta 被引量:8
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作者 LI Chun-Hai ZHANG Gang-Ya +6 位作者 YANG Lin-Zhang LIN Xian-Gui HU Zheng-Yi DONG Yuan-Hua CAO Zhi-Hong ZHENG Yun-Fei DING Jin-Long 《Pedosphere》 SCIE CAS CSCD 2007年第2期209-218,共10页
A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta.... A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta. The pollen and phytolith analyses of two soil profiles from the northeastern part of this site were carried out to trace the agricultural practices of the Neolithic period. The phytolith results showed that rice domestication in the Yangtze River Delta could be traced back to as early as the Majiabang Culture. The pollen assemblage also revealed low levels of aquatic species, similar to that in modern paddy fields. This finding suggested that humans might have removed weeds for rice cultivation during the Neolithic period. Thus, pollen analysis in association with phytolith analysis was a promising method for identifying ancient paddy fields. 展开更多
关键词 ancient paddy fields Neolithic period pollen analysis phytolith analysis Yangtze River Delta
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A Modified Model of Ecological Footprint Accounting and Its Application to Cropland in Jiangsu,China 被引量:21
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作者 LIU Qin-Pu LIN Zhen-Shan +1 位作者 FENG Nian-Hua LIU Yong-Mei 《Pedosphere》 SCIE CAS CSCD 2008年第2期154-162,共9页
Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and app... Based on the theory of emergy analysis,a modified model of ecological footprint accounting,termed emergetic ecological footprint(EMEF)in contrast to the conventional ecological footprint(EF)model,is formulated and applied to a case study of Jiangsu cropland,China.Comparisons between the EF and the EMEF with respect to grain,cotton,and food oil were outlined.Per capita EF and EMEF of cropland were also presented to depict the resources consumption level by comparing the biocapacity(BC)or emergetic biocapacity(EMBC,a new BC calculation by emergy analysis) of the same area.In the meanwhile,the ecological sustainability index(ESI),a new concept initiated by the authors, was established in the modified model to indicate and compare the sustainability of cropland use at different levels and between different regions.The results from conventional EF showed that per capita EF of the cropland has exceeded its per capita BC in Jiangsu since 1986.In contrast,based on the EMBC,the per capita EMEF exceeded the per capita EMBC 5 years earlier.The ESIs of Jiangsu cropland use were between 0.7 and 0.4 by the conventional method,while the numbers were between 0.7 and 0.3 by the modified one.The fact that the results of the two methods were similar showed that the modified model was reasonable and feasible,although some principles of the EF and EMEF were quite different. Also,according to the realities of Jiangsu cropland use,the results from the modified model were more acceptable. 展开更多
关键词 CROPLAND ecological footprint model ecological sustainability index EMERGY
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Remote Sensing Monitoring of Tobacco Field Based on Phenological Characteristics and Time Series Image―A Case Study of Chengjiang County, Yunnan Province, China 被引量:9
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作者 PENG Guangxiong DENG Lei +2 位作者 CUI Weihong MING Tao SHEN Wei 《Chinese Geographical Science》 SCIE CSCD 2009年第2期186-193,共8页
Using three-phase remote sensing images of China-Brazil Earth Resources Satellite 02B (CBERS02B) and Landsat-5 TM, tobacco field was extracted by the analysis of time series image based on the different phenological c... Using three-phase remote sensing images of China-Brazil Earth Resources Satellite 02B (CBERS02B) and Landsat-5 TM, tobacco field was extracted by the analysis of time series image based on the different phenological characteristics between tobacco and other crops. The spectral characteristics of tobacco and corn in luxuriant growth stage are very similar, which makes them difficult to be distinguished using a single-phase remote sensing image. Field film after tobacco seedlings transplanting can be used as significant sign to identify tobacco. Remote sensing interpre- tation map based on the fusion image of TM and CBERS02B's High-Resolution (HR) camera image was used as stan- dard reference material to evaluate the classification accuracy of Spectral Angle Mapper (SAM) and Maximum Like- lihood Classifier (MLC) for time series image based on full samples test method. SAM has higher classification accu- racy and stability than MLC in dealing with time series image. The accuracy and Kappa of tobacco coverage extracted by SAM are 83.4% and 0.692 respectively, which can achieve the accuracy required by tobacco coverage measurement in a large area. 展开更多
关键词 TOBACCO phenological characteristics time series image remote sensing
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Some Fertility Characteristics and Fertilizer Requirements of a Newly Reclaimed Upland Red Soil Derived from Quaternary Red Clay
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作者 MA MAOTONG and XIE JIANCHANG (Institute of Soil Science, the Chinese Academy of Sciences, Nanjing 210008 China) 《Pedosphere》 SCIE CAS CSCD 2000年第4期373-382,共10页
A series of field experiments from 1990 to 1994 in Yingtan, Jiangxi Province, were conducted on an upland red soil derived from Quaternary red clay which had been reclaimed three years before the experiments, in order... A series of field experiments from 1990 to 1994 in Yingtan, Jiangxi Province, were conducted on an upland red soil derived from Quaternary red clay which had been reclaimed three years before the experiments, in order to study the fertility characteristics and fertilizer requirements of the newly reclaimed soil. The field experiments included that on nutrient characteristics and fertilizer effect, that on K-supplying potential and K-Mg relationship, that on fertilization rates of K and N, etc. The newly reclaimed upland soil was low in both N and P, and its responses to nitrogen and phosphate application were very significant. The K-supplying potential was also low, so the soil was highly responsive to K fertilizer. The effect of Ca and Mg fertilizers was not so great for the reason that certain amounts of Ca and Mg were incorporated into the soil through application of calcium magnesium phosphate during land leveling before the experiments. Among the four micronutrients, B, Mo, Zn and Cu, B had the greatest effect on the soil. The fertilizer requirements of the soil were in an order of P and N > K > lime and B > Mg > Mo, Zn and Cu. Eight crops tested had different fertilizer-requiring characteristics. Rapeseed was very sensitive to P and B fertilizers. Barely was especially sensitive to P and lime and it also responded to B, Mo, Zn and Cu. And sweet potato was especially sensitive to K. 展开更多
关键词 fertility characteristics fertilizer requirement newly reclaimed upland soil
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Co-occurrence Patterns of Above-ground and Below-ground Mite Communities in Farmland of Sanjiang Plain, Northeast China 被引量:7
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作者 LIN Lin GAO Meixiang +3 位作者 LIU Dong ZHANG Xueping WU Haitao WU Donghui 《Chinese Geographical Science》 SCIE CSCD 2014年第3期339-347,共9页
One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, litt... One of the fundamental questions in community ecology is whether communities are random or formed by deterministic mechanisms. Although many efforts have been made to verify non-randomness in community structure, little is known with regard to co-occurrence patterns in above-ground and below-ground communities. In this paper, we used a null model to test non-randomness in the structure of the above-ground and below-ground mite communities in farmland of the Sanjiang Plain, Northeast China. Then, we used four tests for non-randomness to recognize species pairs that would be demonstrated as significantly aggregated or segregated co-occurrences of the above-ground and below-ground mite communities. The pattern of the above-ground mite commu- nity was significantly non-random in October, suggesting species segregation and hence interspecific competition. Additionally, species co-occurrence patterns did not differ from randomness in the above-ground mite community in August or in below-ground mite com- munities in August and October. Only one significant species pair was detected in the above-ground mite community in August, while no significant species pairs were recognized in the above-ground mite community in October or in the below-ground mite communities in August and October. The results indicate that non-randomness and significant species pairs may not be the general rule in the above-ground and below-ground mite communities in farmland of the Sanjiang Plain at the fine scale. 展开更多
关键词 above-ground mite below-ground mite mite communities co-occurrence patterns interspecific competition species pairassociations
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Genetic variation and population dispersal of Yangtze voles Microtus fortis calamorum in the Dongting Lake region 被引量:1
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作者 Zongming GUO Pengfei SONG +5 位作者 Cong GUO Zhaobin SONG Yong WANG Bo LI Meiwen ZHANG Jianghong RAN 《Current Zoology》 SCIE CAS CSCD 2012年第2期211-220,共10页
To understand genetic variation and population dispersal in the Yangtze vole Microtusfortis calamorum distributed in the Dongting Lake region, 144 individuals were collected from six habitat patches. The mitochondrial... To understand genetic variation and population dispersal in the Yangtze vole Microtusfortis calamorum distributed in the Dongting Lake region, 144 individuals were collected from six habitat patches. The mitochondrial DNA control region was sequenced and 17 haplotypes were observed. Of the six investigated populations, haplotype and nucleotide diversities of those from larger patches were higher than those from smaller patches. Nonparametric correlation analysis showed that patch size had a positive correlation with haplotype diversity (r = 0.943, P 〈 0.01). A neighbour-joining tree of the 17 haplotypes showed no geo- graphic genetic structure among the six populations. Analysis of isolation by distance showed that genetic differentiation among the six populations was not positively related to geographic distance. Analysis of mismatch distribution indicated that the voles had passed through a population expansion. The pattern of haplotype distribution in the Changsha population suggests that the population was established by a founder effect 展开更多
关键词 Microtusfortis calamorum mitochondrial DNA control region genetic structure Dongting Lake Habitat patch
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