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商务部“汇源案”的反垄断思考 被引量:3
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作者 陈志广 《东岳论丛》 CSSCI 北大核心 2010年第5期42-47,共6页
商务部"汇源案"是严格意义上的中国反垄断"第一案",很多经验教训值得总结。就商务部已公布的信息看,"汇源案"结论的成立存在许多"证明缺口",因而许多信息还需要适时适当地公布。"汇源案&q... 商务部"汇源案"是严格意义上的中国反垄断"第一案",很多经验教训值得总结。就商务部已公布的信息看,"汇源案"结论的成立存在许多"证明缺口",因而许多信息还需要适时适当地公布。"汇源案"的成功之处是市场界定,相关内容可以作为后面的标准。"汇源案"的不足之处在于:一是忽视并购性质的界定,没有运用简单的市场份额标准,使反垄断在市场竞争中的引导作用大打折扣;二是不适当地运用杠杆原理等相对复杂的经济学内容,容易在反垄断和市场竞争中引发混乱反应;三是没有充分尊重相关当事人的权利和审慎权衡竞争利弊,容易给相关当事人和整个市场造成不利影响。 展开更多
关键词 并购 反垄断 “汇源案” 证明缺口
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朱新礼和他的“汇源百分百”
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作者 陈少志 《职业技术教育》 北大核心 2002年第32期18-21,共4页
关键词 朱新礼 沂源县 补偿贸易方式 罐头厂 果汁行业 产品品牌 “汇源”
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Effects of carbon sink fisheries ecosystems
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作者 周胜杰 贾婷婷 +5 位作者 李连星 张扬 刘兴 陈成勋 王庆奎 孙学亮 《Marine Science Bulletin》 CAS 2015年第2期89-96,共8页
Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 (carbon dioxide) emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO... Currently, due to the burning of fossil fuels and changes in land use patterns, a lot of CO2 (carbon dioxide) emissions into the air, the amount of CO2 in the air is extremely increased. According to the research CO2 is the main component of greenhouse gases and the main culprit of causing the greenhouse effect. The ocean is a huge repository of carbon, water can dissolve a large amount of CO2, in the ocean, a large number of plants and planktonic algae absorb CO2 to produce 02, It is a very large gathering place (sink). At the same time, CO2 aggregation in the ocean seawater acidity increases, impact on fishery resources, sources and sinks of CO2 were discussed in the paper. 展开更多
关键词 source and sink greenhouse gases ecologicalsystem fishery resources
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The Structures of the AR Sequences of Tilted Algebras
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作者 章璞 《Chinese Quarterly Journal of Mathematics》 CSCD 1992年第3期58-65,共8页
In this paper,We give the forms of AR sequences of a tilted algebra with terms all belonging to x(A_T),or all belonging to y(A_T).The sink maps of a tilted algebra which end at the indecompos able projective modules a... In this paper,We give the forms of AR sequences of a tilted algebra with terms all belonging to x(A_T),or all belonging to y(A_T).The sink maps of a tilted algebra which end at the indecompos able projective modules and the source maps of starting at the indecomposable injective modules are also obtained.These results together with the connecting sequecnes given in [3] determine the AR quiver of the tilted algcbra,morever,this can be done directly from the AR quiver of the correspond ing hereditary algebra. 展开更多
关键词 tilted algebra AR sequences
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Effects of tip-pruning treatment on source-sink regulation of Catharanthus roseus seedlings 被引量:1
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作者 GAO Yang ZHANG Xue-ke GUO Xiao-rui SUN Yan-fei ZU Yuang-gang 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第4期326-328,共3页
Fifty cultivated Catharanthus roseus seedlings were selected for tip-pruning treatment and the effects of tip-pruning on seedling growth and source-sink regulation were investigated for revealing physiological mechani... Fifty cultivated Catharanthus roseus seedlings were selected for tip-pruning treatment and the effects of tip-pruning on seedling growth and source-sink regulation were investigated for revealing physiological mechanisms of plants. The results showed that tip-pruning treatment resulted in obvious inhibition of apical dominance and enhancement of branching numbers. The contents of soluble sugars, acid sucrose invertase activity (AI) had a great change in differently positional leaves of the seedling. The sink strength in tip leaves of seedlings dramatically declined after tip-pruning treatment, while that in the leaves at the middle and bottom of seedlings had no obvious changes. The inhibition of apical dominance of tip leaves of seedlings was caused by the diminished sink strength due to tip-pruning treatment, 展开更多
关键词 Catharanthus roseus (L.) G. Don Source-sink regulation Tip-pruning Apical dominance
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Comparison of two double-moment microphysics schemes in aspects of warm-rain droplet spectra and raindrop budget 被引量:1
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作者 LEI Hengchi GUO Jiaxu +1 位作者 CHEN Di YANG Jiefan 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第6期424-433,共10页
Simulation results of the WDM6 scheme and the Thompson scheme,both of which are commonly-used double-moment bulkmicrophysics schemes,are compared within theWeather Research and Forecasting model.The purpose of the com... Simulation results of the WDM6 scheme and the Thompson scheme,both of which are commonly-used double-moment bulkmicrophysics schemes,are compared within theWeather Research and Forecasting model.The purpose of the comparison is to study the difference in the aspects of the warm-rain hydrometeor number concentrations,the droplet size distributions,and the budgets of the rain mixing ratio and number concentration.It is found that the WDM6 scheme overestimates the ratio and the amount of large precipitation,and underestimates those of small precipitation,compared to the Thompson scheme.The cloud number concentration(CNC)predicted in the WDM6 scheme is one to three orders ofmagnitude smaller than that of the Thompson scheme,which is set to the specific valueof CNC.The cloud droplet spectra of the WDM6 scheme are broader.The WDM6 scheme produces a larger rain number concentration and smaller mass mean diameter of raindrops under the influence of both warm and cold rain processes—specifically,autoconversion and melting of snow and graupel.The WDM6 scheme produces a larger autoconversion rate and smaller total melting rate of snow and graupel than the Thompson scheme in the rain mixing ratio budget.The sign of the difference in the rain-cloud collection varieswith region,and the rain-cloud collection process together with evaporation of rain have a major influence on the sign of the surface precipitation difference between the two schemes. 展开更多
关键词 WDM6 scheme Thompson scheme droplet number concentration droplet size distribution raindrop budget analysis
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The impacts of modeling global CO2 concentrations with GEOS-Chem using different ocean carbon fluxes
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作者 ZHANG Shan TIAN Xiangjun 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第5期343-348,共6页
The rise in atmospheric carbon dioxide(C02)concentrations caused by human activities is leading to global climate change,which poses a threat to human development and survival.This study analyzed the distribution of t... The rise in atmospheric carbon dioxide(C02)concentrations caused by human activities is leading to global climate change,which poses a threat to human development and survival.This study analyzed the distribution of the ocean carbon flux with interannual changes and compared it with the climatological ocean carbon flux to deepen our understanding of carbon sources and sinks.To simulate global CO2 concentrations for the years2008-2010,the ocean carbon flux with interannual changes and the climatological ocean carbon flux were used to drive the GEOS-Chem model,an atmospheric chemical transport model.The simulated values were compared with the CO2 concentrations at nine observation stations to explore the influence of interannual changes in the ocean carbon fluxes on the simulated CO2 concentrations.The authors found that the difference between the two simulation results was greater in the Southern Hemisphere all year,and the difference in autumn was the largest.Compared with the observations,the simulated CO2 concentration of the ocean carbon flux with interannual changes is closer to the observations,indicating that this simulation is more accurate. 展开更多
关键词 Carbon sources and sinks CO2 concentration GEOS-Chem model Ocean carbon fluxes
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A Study of the Main Obstacles to the Development of Advanced Lexical Competence
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作者 邝斯琪 《Sino-US English Teaching》 2007年第3期11-17,共7页
The present study is to explore the main obstacles to the development of lexical competence in advanced English study. It is conducted by having questionnaires and interviews among 220 students and by analyzing the te... The present study is to explore the main obstacles to the development of lexical competence in advanced English study. It is conducted by having questionnaires and interviews among 220 students and by analyzing the teaching materials. The findings to the study indicate that the main obstacles are caused from the following aspects: neglecting the importance of developing vocabulary in the advanced study; neglecting activating the students' directing sense and detecting sense to difficult words; low rate of word recurrence in the teaching materials; requiring distinguishing the shade of the difference between synonyms excessively and too meticulously; overemphasizing the "negative transfer" of mother tongue; and some other obstacles to the development of lexical competence. 展开更多
关键词 advanced lexical competence word recurrence mentality resource
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Does landscape structure contribute to the long-term maintenance of generalized parasitism in cowbirds?
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作者 Scott ROBINSON Wendy SCHELSKY Jeffrey HOOVER 《Chinese Birds》 CSCD 2013年第1期31-38,共8页
Unlike most brood parasites, several species of cowbird (Molothrus) are generalists that parasitize multiple host species across their range and within the same communities; likewise, there is little evidence that ind... Unlike most brood parasites, several species of cowbird (Molothrus) are generalists that parasitize multiple host species across their range and within the same communities; likewise, there is little evidence that individuals within a population specialize on host species. This situation has variously been attributed to the recency of cowbird evolution (the 'evolutionary lag' hypothesis) or to hidden costs of rejection by hosts (the 'equilibrium' hypothesis). Both hypotheses have some support as cowbirds are indeed a relatively young clade compared with more specialized cuckoos and cowbirds are capable of sophisticated behaviors such as retaliation against rejection ('mafia' behaviors) that would select for acceptance of cowbird eggs. Nevertheless, many species in the Americas have evolved specialized defenses against cowbird parasitism, almost all of which live in more open habitats (e. g., grasslands, shrublands, riparian strips), which indicates that coevolutionary processes can operate in ways that select for host defenses in spite of cowbird counterdefenses. We propose that the structure of landscapes in North America may explain why forest-nesting birds lack defenses against parasitism and reinforce the long-term maintenance of generalized brood parasitism in cowbirds. Because cowbirds require open habitats in which to feed, they are rare or absent in large forest tracts, which dominate much of the forest cover of the Americas. These tracts act as 'source habitats' that produce surplus young that recolonize populations in smaller, fragmented forest patches in which rates of both cowbird parasitism and nest predation are very high ('sink' habitats). Evolution of antiparasite adaptations would be very slow in this situation because most hosts are produced in areas where there is little or no cowbird parasitism. In addition, the interplay of host breeding dispersal, source-sink metapopulation dynamics, and fragmented forest habitat could further deter the evolution of host defenses against parasitism. Therefore, as long as large forest tracts remain widespread in North America, most forest birds will likely continue to lack defenses against cowbird parasitism, guaranteeing a steady supply of na ve hosts in forest habitats, even in fragmented landscapes. This situation will, in turn, favor host generalist cowbirds that actively avoid more open habitats in favor of parasitizing forest bird communities. These forest communities may also act as source populations for cowbirds, which might pump surplus generalist cowbirds into more open habitats further slowing the coevolutionary process. As long as large forest tracts are a common part of the landscape, generalist parasitism may persist indefinitely. 展开更多
关键词 brood parasitism COWBIRD forest fragmentation geographic mosaic theory of coevolution nest predation source-sink metapopulation dynamics
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Mgr Gordana Ljubicic on Translation
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作者 Gordana Ljubicic 《Journal of Literature and Art Studies》 2018年第4期582-588,共7页
The job of a translator is not an easy one. Very often, when translating from one language to another, the translator is faced with a lot of difficulties. The difficulties arise from the non-parallel structures of dif... The job of a translator is not an easy one. Very often, when translating from one language to another, the translator is faced with a lot of difficulties. The difficulties arise from the non-parallel structures of different languages, but there are other reasons, too. Although the translator is, in most cases, familiar with the grammar and syntax of the source-language, the problems arise when it comes to words. New words are produced every day in many different ways. Some of these new coinages acquire the status of the regular words of the English vocabulary, but some disappear with the changing of the situation for which they were invented. Very often, these new words are highly imaginative and clever products, but the problem for the translator is how to translate them. Is it possible to find an equivalent in the Serbian language for every newly invented word? Is it possible to translate word for word? And what is the role of a translator in that process? 展开更多
关键词 TRANSLATING TRANSLATOR new words foreign language PROBLEMS
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Enhanced nitrous acid(HONO)formation via NO_(2)uptake and its potential contribution to heavy haze formation during wintertime
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作者 Zirui Liu Rong Yang +6 位作者 Jingyun Liu Keding Lu Guiqian Tang Yuepeng Pan Dongsheng Ji Yuesi Wang Bo Hu 《Atmospheric and Oceanic Science Letters》 2024年第6期15-20,共6页
full understanding of the sources of atmospheric nitrous acid(HONO)in the polluted urban atmosphere re-mains a challenge.In this study,ambient HONO and relevant species were measured during January 2019 at an urban si... full understanding of the sources of atmospheric nitrous acid(HONO)in the polluted urban atmosphere re-mains a challenge.In this study,ambient HONO and relevant species were measured during January 2019 at an urban site in Beijing,China,and a budget analysis of HONO was conducted using a box model combined with field observations.Large nighttime“missing sources”of HONO were identified on heavily polluted days based on traditional sources,which had a significant correlation with the relative humidity,ammonia(NH_(3)),and aerosol surface area,and the promotional effect of NH_(3)for nitrogen dioxide(NO_(2))uptake on the wet aerosol surface was discussed.Then,an updated parameterization scheme for quantifying the enhanced heterogeneous reactions of NO_(2)on aerosol surfaces is proposed,and the missing nighttime sources of HONO could be substantially com-pensated after the new scheme was incorporated.Further evaluation on the contributions of HONO to hydroxyl radicals was conducted,and the authors found that the photolysis of HONO played a dominant role in the primary OH production on the polluted days(78%-90%).The study reveals great potential of an NH3-enhanced uptake coefficient of NO_(2)on the aerosol surface in the nocturnal HONO budget,and highlights the significance of HONO in the strong atmospheric oxidation capability during episodes with a heavily polluted atmosphere. 展开更多
关键词 Nitrous acid Budget analysis Heterogeneous reactions of NO_(2) Heavy pollution episodes Atmospheric oxidation capacity
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The Heat Island Effect Response to the Urban Landscape Pattern of Haikou based on the“Source-Sink”Theory 被引量:3
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作者 LI Yujie FU Hui 《Journal of Resources and Ecology》 CSCD 2022年第2期257-269,共13页
The Landsat images of the 2000,2005,2010,2015,2018 are selected as the data source to retrieve land cover and surface temperature data.The contribution of Sink-Source landscape pattern to the heat island and its ecolo... The Landsat images of the 2000,2005,2010,2015,2018 are selected as the data source to retrieve land cover and surface temperature data.The contribution of Sink-Source landscape pattern to the heat island and its ecological effects on urban and rural gradient were analyzed by using Heat Index(HI),Sink and Source Landscape Contribution(CI_(sink),CI_(source))and Landscape Effect Index(LI)in Haikou.The results show that the heat island is concentrated on the West Coast,and in the central urban and Jiangdong New Area;the HI shows a pattern of decreasing value with the following land types:“Bare land>Artificial surface﹥Source landscape>Shrub grassland>Farmland>Sink landscape>Woodland>Water body”.In the central city section,the CI_(sink) and CI_(source) are relatively large in these five periods.The LI decreases rapidly along the urban-rural gradient,promoting the Urban Heat Island(UHI)to a large degree.In contrast,the suburban area contributes to a lesser degree.Overall,the LI fluctuates,the proportion of mitigating UHI is large,and there is a second peak outside the city center.The existing Source-Sink Landscape contributes the most to UHI in the central urban area,and this contribution decreases along the urban-rural gradient.With the continuous expansion of city-town areas,the proportion of Sink areas has increased along the gradient,and the proportion of Source areas has subsequently declined,resulting in the spatial transfer and diffusion of UHI.Therefore,a UHI mitigation strategy based on the theory of regional landscape systems is proposed here. 展开更多
关键词 landscape pattern Urban Heat Island gradient analysis “Source-Sink”Theory Haikou
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The role of soluble sugars during drought in tropical tree seedlings with contrasting tolerances 被引量:1
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作者 Michael J.O’Brien Annabelle Valtat +3 位作者 Samuel Abiven Mirjam S.Studer Robert Ong Bernhard Schmid 《Journal of Plant Ecology》 SCIE CSCD 2020年第4期389-397,共9页
Aims Non-structural carbohydrates(NSCs)are plant storage compounds used for metabolism,transport,osmoregulation and regrowth following the loss of plant tissue.Even in conditions suitable for optimal growth,plants con... Aims Non-structural carbohydrates(NSCs)are plant storage compounds used for metabolism,transport,osmoregulation and regrowth following the loss of plant tissue.Even in conditions suitable for optimal growth,plants continue to store NSCs.This storage may be due to passive accumulation from sink-inhibited growth or active reserves that come at the expense of growth.The former pathway implies that NSCs may be a by-product of sink limitation,while the latter suggests a functional role of NSCs for use during poor conditions.Methods Using 13C pulse labelling,we traced the source of soluble sugars in stem and root organs during drought and everwet conditions for seedlings of two tropical tree species that differ in drought tolerance to estimate the relative allocation of NSCs stored prior to drought versus NSCs assimilated during drought.We monitored growth,stomatal conductance,stem water potential and NSC storage to assess a broad carbon response to drought.Important Findings We found that the drought-sensitive species had reduced growth,conserved NSC concentrations in leaf,stem and root organs and had a larger proportion of soluble sugars in stem and root organs that originated from pre-drought storage relative to seedlings in control conditions.In contrast,the drought-tolerant species maintained growth and stem and root NSC concentrations but had reduced leaf NSCs concentrations with a larger proportion of stem and root soluble sugars originated from freshly assimilated photosynthates relative to control seedlings.These results suggest the drought-sensitive species passively accumulated NSCs during water deficit due to growth inhibition,while the drought-tolerant species actively responded to water deficit by allocating NSCs to stem and root organs.These strategies seem correlated with baseline maximum growth rates,which supports previous research suggesting a trade-off between growth and drought tolerance while providing new evidence for the importance of plasticity in NSC allocation during drought. 展开更多
关键词 ^(13)C labelling carbohydrate storage drought tolerance hydraulic function Shorea parvifolia Shorea beccariana source–sink allocation
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Preliminary Estimation of Soil Carbon Sequestration of China’s Forests during 1999–2008 被引量:4
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作者 WANG Bin LIU Moucheng ZHOU Zhichun 《Journal of Resources and Ecology》 CSCD 2022年第1期17-26,共10页
The National Forest Inventory(NFI)is an important resource for estimating the national carbon balance(These data were unpublished data,and we could only obtain the data before 2008 through data search by now).Based on... The National Forest Inventory(NFI)is an important resource for estimating the national carbon balance(These data were unpublished data,and we could only obtain the data before 2008 through data search by now).Based on the data from sample plots,the literature,and NFI,as well as the relationships between volume,biomass,annual litterfall and soil respiration of different forest types,the net ecosystem production(NEP),changes in forest biomass carbon storage(△Cbiomass)and non-respiratory losses(NR)of China’s forests during 1999-2008 were estimated,and the forest soil carbon sequestration(△Csoil)was assessed according to the carbon balance principle of the forest ecosystem(△Csoil=NEP-NR-△Cbiomass).The results showed that the total NEP,△Cbiomass,NR and△Csoil values for China’s forests were 157.530,48.704,31.033 and 77.793 Tg C yr^(-1) respectively,and average NEP,△Cbiomass,NR,and△Csoil values were 101.247,31.303,19.945 and 49.999 g C m^(-2) yr^(-1) respectively.There were large spatial differences in forest soil carbon sequestration in different parts of China.The forest soil in Jiangxi,Hunan,Zhejiang,Fujian,Anhui,Shanxi,Shaanxi,Guangxi and Liaoning served as carbon sources and the carbon released was about 25.507 Tg C yr^(-1).The other 22 provinces served as carbon sinks and the average carbon sequestration by forest soil came to 103.300 Tg C yr^(-1).This research established a method for evaluating soil carbon sequestration by China’s forests based on the NFI,which is a useful supplement to current statistical data-based studies on the forest ecosystem carbon cycle,and can promote comparable studies on forest soil carbon sequestration with consistent research methods at the regional scale. 展开更多
关键词 carbon balance forest ecosystem national forest inventory soil carbon sequestration
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