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Ratios of Closely Related Elements in Soil and Their Implications 被引量:1
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作者 XINGGUANG-XI HOUWEN-HUA 《Pedosphere》 SCIE CAS CSCD 1991年第4期333-343,共11页
This paper has investigated the ratios of closely related elements such as Mn,Cr,V,Ni,Co,Cu,Pb,Cd,Ba,Sr,La and Ce in the major soils of China,and the factors affecting them,and explored their use as indicators in soil... This paper has investigated the ratios of closely related elements such as Mn,Cr,V,Ni,Co,Cu,Pb,Cd,Ba,Sr,La and Ce in the major soils of China,and the factors affecting them,and explored their use as indicators in soil formation,material transport and environmental pollution.Results show that the effect of soil-forming processes on the ratios of closely related elements varied with different elements,and became greater in the sequence of Ce/La <V/Cr≈Ni/Co<Zn/Cu≈Zn/Pb<Zn/Cd<Mn/Cr<Ba/Sr.The magnitude of the variation in the ratios of closely related elements depended on the chemical properties of the elements themselves,on the one hand,and the parent material and climatic conditions on the other.The ratio of Ba/Sr showed a distinct zonality,decreasing gradually in the sequence:cool temperate zone acid soils>grassland soils>desert soils and increasing gradually from the semi-arid subhumid zone soils>the temperate zone neutral soils>the north subtropic zone soils>tropical and subtropical acid soils. 展开更多
关键词 abundance of elements material transport ratios of closely related elements soil-forming processes
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China's development without close relation with the world
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《开放导报》 1999年第6期1-1,共1页
关键词 China’s development without close relation with the world
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Close Neighbors Plus Relatives──An unforgettable Trip to the Philippines
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作者 Wang Fengying 《International Understanding》 1996年第2期13-14,共2页
At the invitation of the.Asian Center of the Philip-pine University,a five-mem-berCAFIU delegation visited the Philippines.The host high-ly regarded our visit,gave us a W arm and courteous recep-tion.Mr.Estrada.
关键词 PLUS An unforgettable Trip to the Philippines Close Neighbors Plus Relatives
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Critical Behavior of the Energy Gap and Its Relation with the Berry Phase Close to the Excited State Quantum Phase Transition in the Lipkin Model
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作者 袁子刚 张平 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第6期1-5,共5页
In our previous work [Phys. Rev. A 85 (2012) 044102], we studied the Berry phase of the ground state and exited states in the Lipkin model. In this work, using the Hellmann-Feynman theorem, we derive the relation be... In our previous work [Phys. Rev. A 85 (2012) 044102], we studied the Berry phase of the ground state and exited states in the Lipkin model. In this work, using the Hellmann-Feynman theorem, we derive the relation between the energy gap and the Berry phase closed to the excited state quantum phase transition (ESQPT) in the Lipkin model. It is found that the energy gap is approximately linearly dependent on the Berry phase being closed to the ESQPT for large N. As a result, the critical behavior of the energy gap is similar to that of the Berry phase. In addition, we also perform a semiclassical qualitative analysis about the critical behavior of the energy gap. 展开更多
关键词 Critical Behavior of the Energy Gap and Its Relation with the Berry Phase Close to the Excited State Quantum Phase Transition in the Lipkin Model
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Species recognition and the divergences in the chemical and ultrasonic signals between two coexisting Rattus species
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作者 Wei-Chao Wang Zhi-Ming Li +3 位作者 Yi Chen Jin-Hua Zhang Jian-Xu Zhang Yao-Hua Zhang 《Current Zoology》 SCIE CAS CSCD 2024年第4期531-538,共8页
The ability to recognize and differentiate between conspecifics and heterospecifics as well as their signals is critical for the coexistence of closely related species.In the genus Rattus,species are morphologically s... The ability to recognize and differentiate between conspecifics and heterospecifics as well as their signals is critical for the coexistence of closely related species.In the genus Rattus,species are morphologically similar and multiple species often coexist.Here,we investigated the interspecific recognition and signal differentiation of two sympatric rat species,the brown rat(Rattus norvegicus,RN)and the Asian house rat(Rattus tanezumi,RT).In a two-way choice test,both RN and RT females showed a preference for conspecific male rats to heterospecific ones.RT females showed a significant preference for accessible urine of males of same species to those of other species,but not for the inaccessi-ble urine.On the other hand,there were significant differences in the structural characteristics of the ultrasonic vocalization emitted by males of these two rat species.Sodium dodecyl sulphate-polyacrylamide gel electrophoresis(SDS-PAGE)and isoelectric focusing electrophoresis unveiled that major urinary proteins(MUPs)in voided urine were more highly expressed in RN males versus RT males.The interspecific dif-ferences of urinary volatile compounds were also discussed.In conclusion,female rats had the ability to distinguish between males of either species. 展开更多
关键词 Asian house rats brown rats closely related species PHEROMONES ultrasonic vocalization.
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C:N:P stoichiometry of Ericaceae species in shrubland biomes across Southern China:influences of climate,soil and species identity 被引量:4
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作者 Qiang Zhang Qing Liu +11 位作者 Huajun Yin Chunzhang Zhao Lin Zhang Guoying Zhou Chunying Yin Zhijun Lu Gaoming Xiong Yuelin Li Jiaxiang Li Wenting Xu Zhiyao Tang Zongqiang Xie 《Journal of Plant Ecology》 SCIE CSCD 2019年第2期346-357,共12页
Aims Carbon(C),nitrogen(N)and phosphorus(P)stoichiometry strongly affect functions and nutrient cycling within ecosystems.However,the related researches in shrubs were very limited.In this study,we aimed to inves-tiga... Aims Carbon(C),nitrogen(N)and phosphorus(P)stoichiometry strongly affect functions and nutrient cycling within ecosystems.However,the related researches in shrubs were very limited.In this study,we aimed to inves-tigate leaf stoichiometry and its driving factors in shrubs,and whether stoichiometry significantly differs among closely related species.Methods We analyzed leaf C,N and P concentrations and their ratios in 32 species of Ericaceae from 161 sites across southern China.We examined the relationships of leaf stoichiometry with environmen-tal variables using linear regressions,and quantified the interactive and independent effects of climate,soil and species on foliar stoi-chiometry using general linear models(GLM).Important Findings The foliar C,N and P contents of Ericaceae were 484.66,14.44 and 1.06 mg g−1,respectively.Leaf C,N and P concentrations and their ratios in Ericaceae were significantly related with latitude and altitude,except the N:P insignificantly correlated with latitude.Climate(mean annual temperature and precipitation)and soil properties(soil C,N and P and bulk density)were significantly influenced element stoichiom-etry.The GLM analysis showed that soil exerted a greater direct effect on leaf stoichiometry than climate did,and climate affected leaf traits mainly via indirect ways.Further,soil properties had stronger influ-ences on leaf P than on leaf C and N.Among all independent factors examined,we found species accounted for the largest proportion of the variation in foliar stoichiometry.These results suggest that species can largely influence foliar stoichiometry,even at a lower taxonomic level. 展开更多
关键词 biogeographic pattern phylogenetic effect closely related species Ericoid Mycorrhiza SHRUB
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Analyzing close relations between target artifacts for improving IR-based requirement traceability recovery
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作者 Haijuan WANG Guohua SHEN +2 位作者 Zhiqiu HUANG Yaoshen YU Kai CHEN 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2021年第7期957-968,共12页
Requirement traceability is an important and costly task that creates trace links from requirements to different software artifacts.These trace links can help engineers reduce the time and complexity of software maint... Requirement traceability is an important and costly task that creates trace links from requirements to different software artifacts.These trace links can help engineers reduce the time and complexity of software maintenance.The information retrieval(IR)technique has been widely used in requirement traceability.It uses the textual similarity between software artifacts to create links.However,if two artifacts do not share or share only a small number of words,the performance of the IR can be very poor.Some methods have been developed to enhance the IR by considering relations between target artifacts,but they have been limited to code rather than to other types of target artifacts.To overcome this limitation,we propose an automatic method that combines the IR method with the close relations between target artifacts.Specifically,we leverage close relations between target artifacts rather than just text matching from requirements to target artifacts.Moreover,the method is not limited to the type of target artifacts when considering the relations between target artifacts.We conduct experiments on five public datasets and take account of trace links between requirements and different types of software artifacts.Results show that under the same recall,the precisions on the five datasets improve by 40%,8%,20%,4%,and6%,respectively,compared with the baseline method.The precision on the five datasets improves by an average of15.6%,showing that our method outperforms the baseline method when working under the same conditions. 展开更多
关键词 Requirement traceability Information retrieval Close relations Target artifacts
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