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“学生超市”的育人思考
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作者 刘杨 田昌运 陈云忠 《中国校外教育(上旬)》 2013年第6期3-3,共1页
利用学生的心仪作品作为学生超市的"商品",借助综合实践活动的平台,挖掘公益性活动的内涵,建筑"造血工程",形成爱心基金会,开展各种主题实践活动,突出学生的实践性、创造性、价值观、人生观。
关键词 学生作品 学生生产力 公益性 能力提升
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Preliminary Analysis of the Jimo Coastal Ecosystem with the Ecopath Model
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作者 SU Meng 《Journal of Ocean University of China》 SCIE CAS 2016年第6期1059-1066,共8页
The Jimo coast encompasses an area of 2157 km^2, and the ecosystem is valuable both socially and economically with regional fisheries substantially contributing to the value. A mass-balanced trophic model consisting o... The Jimo coast encompasses an area of 2157 km^2, and the ecosystem is valuable both socially and economically with regional fisheries substantially contributing to the value. A mass-balanced trophic model consisting of 15 functional ecological groups was developed for the coastal ecosystem using the Ecopath model in Ecopath with Ecosim(Ew E) software(version 6.4.3). The results of the model simulations indicated that the trophic levels of the functional groups varied between 1.0 and 3.76, and the total production of the system was estimated to be 5112.733 t km^(-2) yr^(-1) with a total energy transfer efficiency of 17.6%. The proportion of the total flow originating from detritus was estimated to be 48%, whereas that from primary producers was 52%, indicating that the grazing food chain dominated the energy flow. The ratio of total primary productivity to total respiration in the system was 3.78, and the connectivity index was 0.4. The fin cycling index and the mean path length of the energy flow were 4.92% and 2.57%, respectively, which indicated that the ecosystem exhibits relatively low maturity and stability. The mixed trophic impact(MTI) procedure suggested that the ecological groups at lower trophic levels dominated the feeding dynamics in the Jimo coastal ecosystem. Overfishing is thought to be the primary reason for the degeneration of the Jimo coastal ecosystem, resulting in a decline in the abundance of pelagic and demersal fish species and a subsequent shift to the predominance of lower-trophic-level functional groups. Finally, we offered some recommendations for improving current fishery management practices. 展开更多
关键词 Ecopath model ecosystem evaluation Jimo coast fisheries management
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Improving Simulation of the Terrestrial Carbon Cycle of China in Version 4.5 of the Community Land Model Using a Revised V_(cmax) Scheme 被引量:4
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作者 WANG Yuan-Yuan XIE Zheng-Hui +1 位作者 JIA Bing-Hao YU Yan 《Atmospheric and Oceanic Science Letters》 CSCD 2015年第2期88-94,共7页
The maximum rate of carboxylation (Vcax) is a key photosynthetic parameter for gross primary produc- tion (GPP) estimation in terrestrial biosphere models. A set of observation-based Vcax values, which take the ni... The maximum rate of carboxylation (Vcax) is a key photosynthetic parameter for gross primary produc- tion (GPP) estimation in terrestrial biosphere models. A set of observation-based Vcax values, which take the ni- trogen limitation on photosynthetic rates into consideration, are used in version 4.5 of the Community Land Model (CLM4.5). However, CLM4.5 with carbon-nitrogen (CN) biogeochemistry (CLM4.5-CN) still uses an inde- pendent decay coefficient for nitrogen after the photosyn- thesis calculation. This means that the nitrogen limitation on the carbon cycle is accounted for twice when CN bio- geochemistry is active. Therefore, to avoid this double nitrogen down-regulation in CLM4.5-CN, the original Vcmax scheme is revised with a new one that only accounts for the transition between Vcmax and its potential value (without nitrogen limitation). Compared to flux tower- based observations, the new Vcmax scheme reduces the root-mean-square error (RMSE) in GPP for China's Mainland by 13.7 g C m-2 yr-1, with a larger decrease over humid areas (39.2 g C m 2 yr-1). Moreover, net primary production and leaf area index are also improved, with reductions in RMSE by 0.8% and 11.5%, respectively. 展开更多
关键词 CLM4.5 Vcmax gross primary production net primary production leaf area index
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Study on Zymomonas Mobilis Growth and Its Relationship with Glutaminase Production by Using Statistical Tools
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作者 Gilcelene Bruzon Joao Batista Buzato Maria Antonia Pedrine Colabone Celligoi 《Journal of Life Sciences》 2010年第4期45-51,共7页
Glutaminase is used industrially to enhance flavor and aroma and to enrich foodstuffs nutritionally. It also has potential for pharmaceutical application as anti-leukemia agent. The bacteria of Zymomonas mobilis has b... Glutaminase is used industrially to enhance flavor and aroma and to enrich foodstuffs nutritionally. It also has potential for pharmaceutical application as anti-leukemia agent. The bacteria of Zymomonas mobilis has been studied for ethanol production, however, there is no study regarding glutaminase production. The aim of the present study was to establish the influencing factors for the growth of Z mobilis and its relationship with glutaminase production using statistical tools. Analysis of variance in blocks was carried out in a complete block design and the Tukey test demonstrated the importance of the components of the culture medium, absence of agitation and fermentation time. Minimum culture medium was used in the optimization varying the glucose concentrations (10, 30, and 50 g/L), glutamine (0, 0.5 and 1g/L) and culture time (18, 24 and 30 hours). Maximum production was obtained at 8.86 U/L glutaminase. Optimized conditions were used in the growth kinetics, where typical exponential growth was observed. Glutaminase production was shown to be related to biomass production. 展开更多
关键词 Zymomonas mobilis glutaminase production Tukey test surface response design.
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"Questionable" Behaviors and Practices in Academic Productivity in Postgraduate Studies in Mexico
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作者 Ana Esther Escalante-Ferrer Luz Marina Ibarra Uribe Cesar Dario Fonseca Bautista 《Sociology Study》 2015年第1期8-22,共15页
This paper reports the results acquired in a research work about "questionable" practices and behaviors in the academic production of researches and postgraduate social sciences and humanities studies of the program... This paper reports the results acquired in a research work about "questionable" practices and behaviors in the academic production of researches and postgraduate social sciences and humanities studies of the programs that are appointed by the National Program of Quality Postgraduate Studies (PNPC, by its acronym in Spanish) in Mexico. Through a qualitative methodology, the authors interpreted some of the arguments that explain and/or justify certain practices in relation to doubled production, authorship, and coauthorship of academic products. In this paper, the authors present and analyze the results that they obtained after reviewing documents produced by professors and students of six postgraduate programs that are taught in two Mexican public universities. At the same time, the authors examine some of the practices that take place within said programs, given the institutional demands of improving finished studies efficiency. One of the hypotheses of this work is the demands that are imposed by external evaluations of academic processes on professors and their programs in order to reach desirable rates with the purpose of maintaining or increasing the levels of productivity, gives way to certain practices that must be analyzed. This work's theoretic framework is constituted by the contributions of career sociology and professional ethics. 展开更多
关键词 ETHICS "questionable" practices and behaviors academic production postgraduate studies
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Kinetic simulating experiment on the secondary hydrocarbon generation of kerogen 被引量:14
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作者 熊永强 王云鹏 +4 位作者 申家贵 肖贤明 刘德汉 耿安松 贾蓉芬 《Science China Earth Sciences》 SCIE EI CAS 2002年第1期13-20,共8页
The kinetic parameters of generation have been obtained for different hydrocarbon classes, including methane, C2-C5 gas hydrocarbons, C6-C13 light hydrocarbons and C13+ heavy hydrocarbons, and vitrinite reflectance (R... The kinetic parameters of generation have been obtained for different hydrocarbon classes, including methane, C2-C5 gas hydrocarbons, C6-C13 light hydrocarbons and C13+ heavy hydrocarbons, and vitrinite reflectance (R°) by the kinetic simulating experiment of kerogen cracking. Then, combined with the detailed geology of Sichuan Basin, the effective gas-generating intensity of the Lower Cambrian source rock is approximately estimated by applying these parameters. 展开更多
关键词 KEROGEN hydrocarbon-generating kinetics gas-generating intensity Sichuan Basin
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Formation and influencing factors of carbonate source rock of the Lower Permian Chihsia Formation in Chaohu region, Anhui Province 被引量:8
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作者 LIU Feng CAI JinGong +1 位作者 LU BingQuan XU JinLi 《Science China Earth Sciences》 SCIE EI CAS 2011年第12期1926-1939,共14页
Highly-mature carbonate source rock is essential to the exploration of oil and gas in southern China. In this study, the carbonate strata in the relatively well-developed Lower Permian Chihsia Formation (located in Ch... Highly-mature carbonate source rock is essential to the exploration of oil and gas in southern China. In this study, the carbonate strata in the relatively well-developed Lower Permian Chihsia Formation (located in Chaohu, Lower Yangtze) were targeted, and the formation and influencing factors of source rock were discussed based on paleoenvironment reconstruction using comprehensive sedimentology, palynofacies, and organic geochemistry data. The results demonstrate that the Chihsia Formation is oxygen-deficient biogenic carbonate sediments, with marked variations in the organic and inorganic components, formed during a period of Permian transgression. The formation of source rock is the combined result of high bioproductivity and oxygen-deficient environment generated by transgression and oxygenation events which frequently occurred during transgression periods. Source rock was affected by self-dilution effects and diagenesis, causing its heterogeneous distribution in many intervals. Source rock is over 40 m thick, and can be identified based on its different organic, biological, and mineral composition characteristics. The carbonate rock appears to require no specific clay content in order to become a source rock. The combination of sedimentology, palynofacies, and organic geochemistry has provided an effective means for evaluating and predicting high-maturity carbonate source rock in the region. 展开更多
关键词 lower Yangtze Chihsia Formation PALYNOFACIES PALEOENVIRONMENT carbonate source rock heterogeneous distribution
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