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Phosphorus status, use and recycling in a Chinese peri-urban region with intensive animal husbandry and cropping systems Results from case study in a Sino-German applied research collaboration project
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作者 Marco ROELCKE Lisa HEIMANN +13 位作者 Yong HOU Jianbin GUO Qiaoyun XUE Wei JIA Anne OSTERMANN Roxana Mendoza HUAITALLA Moritz ENGBERS Clemens OLBRICH Roland W.SCHOLZ Joachim CLEMENS Frank SCHUCHARDT Rolf NIEDER Xuejun LIU Fusuo ZHANG 《Frontiers of Agricultural Science and Engineering》 2019年第4期388-402,共15页
The Sino-German research collaboration project,"Recycling of organic residues from agricultural and municipal origin in China"(2008–2012),comprising different interdisciplinary research groups,and also Germ... The Sino-German research collaboration project,"Recycling of organic residues from agricultural and municipal origin in China"(2008–2012),comprising different interdisciplinary research groups,and also German small and medium-sized enterprises,aimed at developing integrated strategies and solutions for the recycling of organic residues in China.In an intensive crop-livestock agricultural region in the Shunyi District of Beijing,five typical cropping systems were investigated.The research was conducted in the form of analyses of phosphorus(P)in soil,plants,animal feed,animal products,manures,mineral and organic fertilizers and the derivation of the corresponding nutrient balances and P flows.The mean annual P balance surplus was492 kg·ha–1·yr–1 P for the vegetable production system,significantly higher(P<0.05)than that for orchards(130 kg·ha–1·yr–1 P)and cereal crops(83 kg·ha–1·yr–1 P).Plant-available P(Olsen-P)concentrations of topsoils(0–20 cm)had good correlations with the amounts of P applied(from mineral and organic sources).Compared to results from the Second Chinese National Soil Survey of 1981,mean concentrations of available P in soils of 19 plots investigated in Shunyi District increased 10-fold(from 7.3 to 60 mg·kg–1)from 1981 to 2009.On average,the critical limit for Olsen-P concentrations(>30 mg·kg–1)that can lead to increased risk of P loss was exceeded in all five cropping systems.With feed additives,the"natural background value"(Chinese Environmental Quality Standard for Soils)of copper and zinc in topsoils was exceeded at several sites.Screening for several substances in the veterinary antibiotic classes of sulfonamides,tetracyclines,and fluoroquinolones revealed widespread topsoil contamination.Calculated livestock densities were 10.6 livestock units per ha arable land in 2007.Animal husbandry is increasingly conducted in large operations,making traditional ways of reuse difficult to apply.Comparing three management systems for treatment of organic residues from a pig 展开更多
关键词 cropping systems life cycle assessment North China Plain balances and nutrient flows transdisciplinary approach
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Effects of ausforming strain on bainite transformation in nanostructured bainite steel
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作者 Hong-liang Fan Ai-min Zhao +2 位作者 Qing-chun Li Hui Guo Jian-guo He 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2017年第3期264-270,共7页
The effects of ausforming strain on bainite transformation in high-carbon low-alloy nanobainite steel were investigated using a Gleeble 3500 thermomechanical simulator machine. The bainite transformation speed at 300&... The effects of ausforming strain on bainite transformation in high-carbon low-alloy nanobainite steel were investigated using a Gleeble 3500 thermomechanical simulator machine. The bainite transformation speed at 300°C was found to be accelerated by ausforming at 300, 600, and 700°C under applied strains ranging from 10% to 50% followed by isothermal transformation at 300°C. The ausformed bainite volume fraction varied with the ausforming strain because of the mechanical stabilization of the deformed austenite. Ausforming at low temperatures not only enhanced the bainite ferrite volume fraction but also refined the microstructure substantially. Although the amount of bainite ferrite might have been reduced with increasing strain, the microstructures were refined by ausforming. © 2017, University of Science and Technology Beijing and Springer-Verlag Berlin Heidelberg. 展开更多
关键词 Alloy steel BAINITE Carbon Enzyme kinetics FERRITE Microstructure Nanostructured materials Phase transitions STRAIN Volume fraction
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Identification of the Disrupted Pathways Associated with Periodontitis Based on Human Pathway Network 被引量:1
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作者 Wen Sun Lin Han +1 位作者 Wenmao Xu Yazhen Sun 《国际感染病学(电子版)》 CAS 2016年第4期93-98,共6页
Objective: The objective of this work is to search for a novel method to explore the disrupted pathways associated with periodontitis(PD) based on the network level.Methods: Firstly, the differential expression genes(... Objective: The objective of this work is to search for a novel method to explore the disrupted pathways associated with periodontitis(PD) based on the network level.Methods: Firstly, the differential expression genes(DEGs) between PD patients and cognitively normal subjects were inferred based on LIMMA package. Then, the proteinprotein interactions(PPI) in each pathway were explored by Empirical Bayesian(EB) coexpression program. Specifically, we determined the 100 th weight value as the threshold value of the disrupted pathways of PPI by constructing the randomly model and confirmed the weight value of each pathway. Meanwhile, we dissected the disrupted pathways under the weight value > the threshold value. Pathways enrichment analyses of DEGs were carried out based on Expression Analysis Systematic Explored(EASE) test. Finally, the better method was selected based on the more rich and significant obtained pathways by comparing the two methods. Results: After the calculation of LIMMA package, we estimated 524 DEGs in all. Then we determined 0.115222 as the threshold value of the disrupted pathways of PPI. When the weight value>0.115222, there were 258 disrupted pathways of PPI enriched in. Additionally, we observed those 524 DEGs that were enriched in 4 pathways under EASE=0.1.Conclusion: We proposed a novel network method inferring the disrupted pathway for PD. The disrupted pathways might be underlying biomarkers for treatment associated with PD. 展开更多
关键词 PERIODONTITIS disrupted pathways proteinprotein interactions EB co-expression
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FRACTAL ANALYSIS APPLIED TO SPATIAL STRUCTURE OF CHINA'S VEGETATION
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作者 ZHU Xiao-hua Patel NILANCHAL +1 位作者 ZUO Wei YANG Xiu-chun 《Chinese Geographical Science》 SCIE CSCD 2006年第1期48-55,共8页
Based on the fractal theory, the spatial structure of China's vegetation has been analyzed quantitatively in this paper. Some conclusions are drawn as the following. 1) The relationships between size and frequency o... Based on the fractal theory, the spatial structure of China's vegetation has been analyzed quantitatively in this paper. Some conclusions are drawn as the following. 1) The relationships between size and frequency of patch area and patch shape index exist objectively for China's vegetation. 2) The relationships between perimeter and area exist objectively for China's vegetation. 3) The fractal dimension of evergreen needleleaf forests on mountains in subtropical and tropical zones is the largest, while the smallest for deciduous broadleafand evergreen needleleaf mixed forests in temperate zone, reflecting the most complex spatial structure for evergreen needleleaf forests on mountains in subtropical and tropical zones and the simplest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone. 4) The fractal dimensions of China's vegetation types tend to decrease from thc subtropics to both sides. 5) The stability of spatial structure of deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone is the largest, while the smallest for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards, reflecting the steadiest for deciduous broadleaf and evergreen needleleaf mixed forests in temperate zone and the most unstable for double-cropping rice, or double-cropping rice and temperate-like grain, and tropical evergreen economic tree plantations and orchards in spatial structure. 6) The stability of spatial structure of China's vegetation tends to decrease from the temperate zone to both sides, it is significantly pertinent to understand the formation, evolution, dynamics and complexity rule of ecosystem of vegetation. 展开更多
关键词 VEGETATION spatial structure FRACTAL fractal dimension China
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