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山西煤盆地热演化与生气作用研究 被引量:7
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作者 李侠 魏永佩 +2 位作者 纪邦师 王满荣 王仲平 《西安工程学院学报》 2000年第2期27-31,共5页
根据山西煤田实际资料 ,建立了推算山西煤盆地最高古地温的数学模式 ,探讨了区内热演化史 ,提出了山西煤盆地于成煤期后 ,曾有两次大的热演化过程 ,一为印支期 ,主要是快速沉降堆积增温阶段 ;一为燕山期 ,主要表现为岩浆区域热叠加增温... 根据山西煤田实际资料 ,建立了推算山西煤盆地最高古地温的数学模式 ,探讨了区内热演化史 ,提出了山西煤盆地于成煤期后 ,曾有两次大的热演化过程 ,一为印支期 ,主要是快速沉降堆积增温阶段 ;一为燕山期 ,主要表现为岩浆区域热叠加增温现象 。 展开更多
关键词 山西 煤层气 古地温 热演化 煤盆地 生气作用
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高效气源灶及其对形成高效气藏的作用 被引量:35
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作者 赵文智 王兆云 +5 位作者 汪泽成 王红军 张水昌 王云鹏 赵长毅 苗继军 《沉积学报》 CAS CSCD 北大核心 2005年第4期709-718,共10页
厘定了高效气源灶的概念和评价指标。高效气源灶是指具有一定分布范围的高有机质丰度气源岩在特定的热力或生物化学营力作用下高效生气,且这一过程与天然气聚集成藏作用在时、空间有良好耦合关系,从而在大中型气藏形成中高效发挥作用的... 厘定了高效气源灶的概念和评价指标。高效气源灶是指具有一定分布范围的高有机质丰度气源岩在特定的热力或生物化学营力作用下高效生气,且这一过程与天然气聚集成藏作用在时、空间有良好耦合关系,从而在大中型气藏形成中高效发挥作用的气源灶。包含两方面涵义,生气的物质基础和生气的热动力学过程。因此,评价指标从三方面考虑,一是气源灶生气强度大,这里沿用戴金星提出的形成大中型气田的评价指标,大于20×108m3/km2;二是主生气期的作用时间短,通过Ⅰ、Ⅱ、Ⅲ型气源岩及原油的生烃动力学研究,以及对我国主要含气盆地气源灶主生气期作用时间统计分析,确定主生气期作用时间小于40Ma,尤以小于20Ma为优;三是主生气期完成时刻距今的时间晚,晚期成藏有利于天然气的保存。高效气源灶对形成高效气藏的贡献在于单位时间内供气数量大,以及由此产生的高效运聚作用和天然气散失数量少等。根据源岩母质类型和生气的动力学过程,我国有三类六种高效气源灶。 展开更多
关键词 高效气源灶 高效成藏作用 生气作用时间 评价指标 油裂解型气源灶
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徐家围子断陷徐南地区气藏超压成因 被引量:2
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作者 狄嘉祥 刘文龙 吴世环 《天然气工业》 EI CAS CSCD 北大核心 2009年第8期42-43,共2页
松辽盆地徐家围子断陷为受徐西、徐中两条断裂控制的箕状断陷,在徐南地区发现有超压气藏存在。利用地球物理和地质资料,从压实不均衡、生烃作用以及泥岩封闭等方面分析了该区的超压成因。研究结果表明,徐南地区地层为正常压实状态,不存... 松辽盆地徐家围子断陷为受徐西、徐中两条断裂控制的箕状断陷,在徐南地区发现有超压气藏存在。利用地球物理和地质资料,从压实不均衡、生烃作用以及泥岩封闭等方面分析了该区的超压成因。研究结果表明,徐南地区地层为正常压实状态,不存在明显或可识别的欠压实沉积过程,地层压力在巨厚的泥岩封闭层下完好保存。生气作用是造成徐南地区气藏超压的主要原因,泥岩封闭为超压的保存提供了良好条件,压实不均衡作用对徐南地区的超压作用不明显。 展开更多
关键词 松辽盆地 徐家围子断陷 异常超压 成因 压实不均衡 生气作用 泥岩封闭
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Effects of Compound Probiotics on Intestine and Intestinal Aeromonas hydrophila of Fish 被引量:3
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作者 朱芝秀 邓舜洲 +4 位作者 张丽珍 徐添乐 李敏 刘小兰 柳仲 《Agricultural Science & Technology》 CAS 2016年第11期2622-2626,共5页
[Objective] This study was conducted to develop compound probiotics that can be used as the alternatives of chemical drugs and antibiotics in aquaculture. [Method] Different concentrations of EM (effective microorgan... [Objective] This study was conducted to develop compound probiotics that can be used as the alternatives of chemical drugs and antibiotics in aquaculture. [Method] Different concentrations of EM (effective microorganisms) and Bacillus amyloliquefaciens were mixed at a ratio of 1:1, and sprayed on fish feed. The growth of intestinal villi of the fishes that had been fed with the feed mixed with compound probiotics for three months was observed; meanwhile, the content of in- testinal Aeromonas hydrophila was detected by real-time quantitative PCR. |Result] The compound probiotics promoted the development of intestinal villi, and inhibited the growth of A. hydrophila, and the effects were also concentration dependent. However, the compound probiotics did not increase the thickness of the intestinal serous layer, muscular layer and submucosal layer. [Conclusion] The compound probiotics we prepared can be used and popularized in aquiculture as it can inhibit the growth of A. hydrophila. 展开更多
关键词 PROBIOTICS Aeromonas hydrophila EFFECTS
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Photosynthetic Responses to Inorganic Carbon in Ulva lactuca Under Aquatic and Aerial States
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作者 邹定辉 高坤山 《Acta Botanica Sinica》 CSCD 2002年第11期1291-1296,共6页
Intertidal macroalgae experience continual alternation of photosynthesis between aquatic state at high tide and aerial state at low tide. The comparative photosynthetic responses to inorganic carbon were investigated... Intertidal macroalgae experience continual alternation of photosynthesis between aquatic state at high tide and aerial state at low tide. The comparative photosynthetic responses to inorganic carbon were investigated in the common intertidal macroalga Ulva lactuca L. along the coast of Shantou between aquatic and aerial state. The inorganic carbon dissolved in seawater at present could fully (at 10 ℃ or 20 ℃) or nearly (at 30 ℃) saturate the aquatic photosynthesis of U. lactuca . However, the aerial photosynthesis was limited by current ambient atmospheric CO 2 level, and such a limitation was more severe at higher temperature (20-30 ℃) than at lower temperature (10 ℃). The carbon_saturated maximal photosynthesis of U. lactuca under aerial state was much greater than that under aquatic state at 10 ℃ and 20 ℃, while the maximal photosynthesis under both states was similar at 30 ℃. The aerial values of K m (CO 2) for photosynthesis were higher than the aquatic values. On the contrary, the values of apparent photosynthetic CO 2 conductance under aerial state were considerably lower than that under aquatic state. It was concluded that the increase of atmospheric CO 2 would enhance the primary productivity of U. lactuca through stimulating the photosynthesis under aerial state during low tide. 展开更多
关键词 Ulva lactuca PHOTOSYNTHESIS inorganic carbon AQUATIC AERIAL atmospheric CO 2 rise
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Partial Nitrification from Domestic Wastewater by Aeration Control at Ambient Temperature 被引量:11
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作者 彭永臻 高守有 +1 位作者 王淑莹 白璐 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期115-121,共7页
The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational param... The objective of this paper was to examine the feasibility of partial nitrification from raw domestic wastewater at ambient temperature by aeration control only. Airflow rate was selected as the sole operational parameter. A 14L sequencing batch reactor was operated at 23℃ for 8 months, with an input of domestic wastewater. There was a prolgrammed decrease of the airflow rate to 28L·h^-1, the corresponding average dissolved oxygen (DO) was 0.32mg·h^-1, and the average nitrite accumulation rate increased to 92.4% in 3 weeks. Subsequently, further increase in the airflow rate to 48L·h^-1 did not destroy the partial nitrification to nitrite, with average DO of 0.60mg·h^-1 and nitrite accumulating rate of 95.6%. The results showed that limited airflow rate to cause oxygen deficiency in the reactor would eventually induce only nitrification to nitrite and not further to nitrate and that this system showed relatively stability at higher airflow rate independent of pH and temperature. About 50% of influent total nitrogen was eliminated coupling with partial nitrification, taking the advantage of low DO during the reaction. 展开更多
关键词 partial nitrification oxygen-limiting condition ambient temperature domestic wastewater
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Seasonal changes in TC and WSOC and their ^13C isotope ratios in Northeast Asian aerosols: land surface–biosphere–atmosphere interactions 被引量:2
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作者 Chandra Mouli Pavuluri Kimitaka Kawamura 《Acta Geochimica》 EI CAS CSCD 2017年第3期355-358,共4页
In order to understand the relative importance of anthropogenic and biological sources of carbonaceous aerosols in Northeast Asia,we measured total carbon(TC)and water-soluble organic carbon(WSOC)and their stable carb... In order to understand the relative importance of anthropogenic and biological sources of carbonaceous aerosols in Northeast Asia,we measured total carbon(TC)and water-soluble organic carbon(WSOC)and their stable carbon isotope ratios(d^(13)C)in total suspended particulates collected from Sapporo,northern Japan(43.07°N,141.36°E)over a 1-year period(during 2 September 2009and 5 October 2010).Temporal variations of TC showed a gradual decrease from mid-autumn to winter followed by a gradual increase to growing season with a peak in early summer.Both d^(13)C_(TC)and d^(13)C_(WSOC)showed very similar temporal trends with a gradual enrichment of^(13)C from mid-autumn to winter followed by a depletion in the^(13)C to early summer and thereafter it remained stable,except for few cases.Based on the results obtained together with the air mass trajectories,we found that biogenic emissions including biological particles(e.g.,pollen)and secondary organic aerosol formation from biogenic volatile organic compounds are the important sources of carbonaceous aerosols in spring/summer whereas fungal spores from soil and biomass burning and enhanced fossil fuel combustion contribute significantly in autumn/winter and in winter,respectively,in Northeast Asia. 展开更多
关键词 Carbonaceous aerosols Stable carbon isotope ratios Sources Northeast Asia
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Quantifying the impacts of fire aerosols on global terrestrial ecosystem productivity with the fully-coupled Earth system model CESM 被引量:2
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作者 LI Fang 《Atmospheric and Oceanic Science Letters》 CSCD 2020年第4期330-337,共8页
Fire is a global phenomenon and a major source of aerosols from the terrestrial biosphere to the atmosphere.Most previous studies quantified the effect of fire aerosols on climate and atmospheric circulation,or on the... Fire is a global phenomenon and a major source of aerosols from the terrestrial biosphere to the atmosphere.Most previous studies quantified the effect of fire aerosols on climate and atmospheric circulation,or on the regional and site-scale terrestrial ecosystem productivity.So far,only one work has quantified their global impacts on terrestrial ecosystem productivity based on offline simulations,which,however,did not consider the impacts of aerosol–cloud interactions and aerosol–climate feedbacks.This study quantitatively assesses the influence of fire aerosols on the global annual gross primary productivity(GPP)of terrestrial ecosystems using simulations with the fully coupled global Earth system model CESM1.2.Results show that fire aerosols generally decrease GPP in vegetated areas,with a global total of−1.6 Pg C yr^−1,mainly because fire aerosols cool and dry the land surface and weaken the direct photosynthetically active radiation(PAR).The exception to this is the Amazon region,which is mainly due to a fire-aerosol-induced wetter land surface and increased diffuse PAR.This study emphasizes the importance of the influence of fire aerosols on climate in quantifying global-scale fire aerosols’impacts on terrestrial ecosystem productivity. 展开更多
关键词 Fire aerosols terrestrial ecosystem gross primary productivity land–atmosphere interaction Earth system model
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Performance of simultaneous nitrification and denitrification in lateral flow biological aerated filter 被引量:1
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作者 龙腾锐 《Journal of Chongqing University》 CAS 2006年第4期223-228,共6页
A new wastewater treatment facility—lateral flow biological aerated filter (LBAF) was developed aiming at solving energy consumption and operational problems in wastewater treatment facilities in small towns. It has ... A new wastewater treatment facility—lateral flow biological aerated filter (LBAF) was developed aiming at solving energy consumption and operational problems in wastewater treatment facilities in small towns. It has the function of nitrification and removing organic substrate. In this study, we focused on the denitrification performance of LBAF and its possible mechanism under thorough aeration. We identified the existence of simultaneous nitrification and denitrification (SND) by analyzing nitrogenous compounds along the flow path of LBAF and supportive microbial microscopy, and studied the effects of air/water ratio and hydraulic loading on the performance of nitrogen removal and on SND in LBAF to find out the optimal operation condition. It is found that for saving operation cost, aeration can be reduced to some degree that allows desirable removal efficiency of pollutants, and the optimal air/water ratio is 10:1. Hydraulic loading less than 0.43 m h?1 hardly affects the nitrification and denitrification performance; whereas higher hydraulic loading is unfavorable to both nitrification and denitrification, far more unfavorable to denitrification than to nitrification. 展开更多
关键词 lateral flow biological aerated filter simultaneous nitrification and denitrification air/water ratio hydraulic loading
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The Characteristics of a Sorption-enhanced Steam-Methane Reaction for the Production of Hydrogen Using CO_2 Sorbent 被引量:15
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作者 吴素芳 T.H.Beum +1 位作者 J.I.Yang J.N.Kim 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2005年第1期43-47,共5页
The objective of the present study is to characterize the production of hydrogen with a sorptionenhanced steam-methane reaction process using Ca(OH)2 as the CO2 adsorbent. Theoretical equilibrium compositions at diffe... The objective of the present study is to characterize the production of hydrogen with a sorptionenhanced steam-methane reaction process using Ca(OH)2 as the CO2 adsorbent. Theoretical equilibrium compositions at different operation conditions were calculated using an iterative method. It was found that with Ca(OH)2 as the CO2 sorbent, the concentration of CO2 adsorption was reduced in the product stream, that gave rise to higher methane conversion and higher H2 concentration. An experimental setup was built to test the theoretical calculation. The effects of sorbents and the particle size of Ca(OH)2 on the concentration of CO2 and H2 were investigated in detail. Results showed that the reactor packed with catalyst and Ca(OH)2 particles produced H2 concentration of 94%. It was nearly 96% of the theoretical equilibrium limit, much higher than H2 equilibrium concentration of 67.5% without CO2 sorption under the same conditions of 500℃, 0.2 MPa pressure and a steam-to-methane ratio 6. In addition, the residual mole fraction of CO2 was less than 0.001. 展开更多
关键词 HYDROGEN reactive-adsorption calcium hydroxide steam-methane reforming
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Degradation of lignite model compounds by the action of white rot fungi 被引量:9
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作者 DU Ying, TAO Xiuxiang, SHI Kaiyi, LI Yang School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou 221000, China 《Mining Science and Technology》 EI CAS 2010年第1期76-81,共6页
Three compounds modeled on the lignite structure were chosen for experimental degradation by different fungi strains. Culture conditions and extracellular enzyme activities were optimized. The growth curves of the str... Three compounds modeled on the lignite structure were chosen for experimental degradation by different fungi strains. Culture conditions and extracellular enzyme activities were optimized. The growth curves of the strains were determined to study mycelium dry weight and protein content changes. Gas chromatography and infrared spectroscopy were used to detect changes of functional groups before and after the action of the fungi on the model compounds. Possible decomposition products and degrada-tion mechanisms were proposed. The research findings show that C. Versicolor and Golden Mushroom can grow in presence of the model compounds. The optimum culture conditions were a pH of 6.0, a carbon-nitrogen ratio of five and a Tween-80 concentration of 0.1%. Newly produced substances were found by gas chromatography. Infrared analysis showed that the model compounds degraded under the action of the microorganisms. 展开更多
关键词 COAL BIOTRANSFORMATION white rot fungi mechanism model compound
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The green fuel from carbon waste: optimization and product selectivity model studies
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作者 Hossein Atashi Fatemeh Rezaeian Ali Akbar Mirzaei 《International Journal of Coal Science & Technology》 EI 2018年第3期399-410,共12页
Increase in greenhouse gases, has made scientists to substitute alternative fuels for fossil fuels. Nowadays, converting biomass into liquid by Fischer-Tropsch synthesis is a major concern for alternative fuels (gaso... Increase in greenhouse gases, has made scientists to substitute alternative fuels for fossil fuels. Nowadays, converting biomass into liquid by Fischer-Tropsch synthesis is a major concern for alternative fuels (gasoline, diesel etc.). Selectivity of Fischer-Tropsch hydrocarbon product (green fuel) is an important issue. In this study, the experimental data has been obtained from three factors; temperature, H2/CO ratio and pressure in the fixed bed micro reactor. T = 543-618 (K), P = 3-10 (bar), H2/CO = 1-2 and space velocity = 4500 (l/h) were the reactor conditions. The results of product modeling for methane (CH4), ethane (C2H6), ethylene (C2H4) and CO conversion with experimental data were compared. The effective parameters and the interaction between them were investigated in the model. H2/CO ratio and pressure and interaction between pressure and H2/CO in ethane selectivity model and CO conversion and interaction between temperature and H2/CO ratio in methane selectivity model and ethylene gave the best results. To determine the optimal conditions for light hydrocarbons, ANOVA and RSM were employed. Finally, products optimization was done and results were concluded. 展开更多
关键词 Selectivity model Fischer-Tropsch synthesis Green fuel OPTIMIZATION Fixed bed micro reactor Alternative fuels
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Role of Periodic Input Composition and Sweeping Gas for Improvement of Hydrogen Production in a Palladium Membrane Reactor by Partial Oxidation of Methane
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作者 Lemnouer Chibane Brahim Djellouli 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第3期577-588,共12页
The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on metha... The partial oxidation of methane under periodic operation over Ni/y/-Al2O3 catalyst was investigated in a Pd-membrane reactor. The effects of key parameters such as the inlet composition and the sweeping, gas on methane conversion and the hydrogen recovery are numerically estalallshed with two penodtc input ttmctlons. In order to analyze the effect of the inputs modulation, the reaction was performed under low steam to methane ratio at a mod-erate temperature and pressure. It was obtained that to achieve process intensification is to operate the process in a periodic way. The main results show that the periodic input functions can improve the performance of the process compared to the optimal steady state operation. Moreover, there is an optimum amplitude of manipulated inputs leads to a maximum of hydrogen recovery. It is noteworthy that the comparison between the predicted performancevia the sinusoidal and the'square ways show that the better'average performance was obtainedwith the square way. 展开更多
关键词 hydrogen production MODULATION periodic operation Pd-membrane reactor
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Effect of precipitation condition on photosynthesis and biomass accumulation and referring to splash erosion status in five typical evergreen tree species in humid monsoon climatic region of subtropical hill-land
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作者 余蔚青 王云琦 +3 位作者 王玉杰 张会兰 王彬 刘勇 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第10期3795-3805,共11页
Negative effect of precipitation on plant photosynthesis was investigated in this work. Stomatal conductance, transpiration rate and net photosynthetic rate were measured before and after each precipitation event, res... Negative effect of precipitation on plant photosynthesis was investigated in this work. Stomatal conductance, transpiration rate and net photosynthetic rate were measured before and after each precipitation event, respectively, and the corresponding precipitation was recorded as well. Moreover, plant dry matter accumulation was counted at the end of our entire experiment. The results show that precipitation fully demonstrates its negative effect on plant photosynthesis under the condition of without water shortage. Although it has not been proved, leaf shape seems to be associated with this effect. Broad-leaved species are less influenced than coniferous and lanceleaf species no matter on the length of variation time or changes in variation values. The different situation among three broad-leaved species seems to illustrate that the effect is also related to the size of single leaf area. The correlation between precipitation and photosynthetic rate variation is analogous to the relationship between precipitation and splash erosion, and in the view of the relationship between plant photosynthetic characteristics and dry mass accumulation, it can be thought that it can reflect the negative impact of precipitation on plant growth by making use of splash erosion. Therefore, a section was added in the traditional plant biomass estimation algorithms by using eco-physiological models, and this was proved to enhance the accuracy of traditional estimation from preliminary verifications. 展开更多
关键词 PRECIPITATION leaf photosynthesis splash erosion dry matter net primary productivity
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Coastal blue carbon: Concept, study method, and the application to ecological restoration 被引量:14
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作者 Jianwu TANG Shufeng YE +5 位作者 Xuechu CHEN Hualei YANG Xiaohong SUN Faming WANG Quan WEN Shaobo CHEN 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第6期637-646,共10页
Coastal blue carbon refers to the carbon taken from atmospheric CO2; fixed by advanced plants(including salt marsh,mangrove, and seagrass), phytoplankton, macroalgae, and marine calcifiers via the interaction of plant... Coastal blue carbon refers to the carbon taken from atmospheric CO2; fixed by advanced plants(including salt marsh,mangrove, and seagrass), phytoplankton, macroalgae, and marine calcifiers via the interaction of plants and microbes; and stored in nearshore sediments and soils; as well as the carbon transported from the coast to the ocean and ocean floor. The carbon sequestration capacity per unit area of coastal blue carbon is far greater than that of the terrestrial carbon pool. The mechanisms and controls of the carbon sink from salt marshes, mangroves, seagrasses, the aquaculture of shellfish and macroalgae, and the microbial carbon pump need to be further studied. The methods to quantify coastal blue carbon include carbon flux measurements, carbon pool measurements, manipulative experiments, and modeling. Restoring, conserving, and enhancing blue carbon will increase carbon sinks and produce carbon credits, which could be traded on the carbon market. The need to tackle climate change and implement China's commitment to cut carbon emissions requires us to improve studies on coastal blue carbon science and policy. The knowledge learned from coastal blue carbon improves the conservation and restoration of salt marshes,mangroves, and seagrasses; enhances the function of the microbial carbon pump; and promotes sustainable aquaculture, such as ocean ranching. 展开更多
关键词 Coastal Blue carbon Ecological restoration Salt marsh Mangrove Seagrass Microbial carbon pump Aquaculture carbon sink
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Analysis of solid-liquid-gas interactions in landfilled municipal solid waste by a bio-hydro-mechanical coupled model 被引量:14
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作者 CHEN YunMin XU XiaoBing ZHAN LiangTong 《Science China(Technological Sciences)》 SCIE EI CAS 2012年第1期81-89,共9页
Based on first-order kinetics of hydrolysis process, biodegradation of municipal solid waste (MSW) is assumed to obey a first-order decay equation which can take the direct effect of water content on biodegradation ... Based on first-order kinetics of hydrolysis process, biodegradation of municipal solid waste (MSW) is assumed to obey a first-order decay equation which can take the direct effect of water content on biodegradation into account. Hydraulic model is an unsaturated-saturated flow model using mass conservation equations for fluids. Mechanical compression of MSW is ex- pressed by a stress-age coupled compression model. Through above models, a one-dimensional (I-D) bio-hydro-mechanical coupled model is established to analyze solid-liquid-gas interactions in landfilled MSW. Values of all the model parameters for current typical Chinese MSW are determined. Numerical analysis of a hypothetical waste sample in a closed system shows that gas pressure and gas concentration is extremely large which might cause severe gas explosion problem. Total gas production is about 267.0 m3 per wet ton of fresh wastes. For another hypothetical landfilled MSW layer, the coupled model predicts a dis- sipation of gas pressure during passive gas collection process. Annual gas production is large at the beginning of biodegradation, and then decreases with time. Surface settlement of the wastes increases quickly initially and then becomes stable with a compression strain of about 0.32 after 20 years. 展开更多
关键词 municipal solid waste solid-liquid-gas interaction gas generation SETTLEMENT
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Host-parasite interactions under extreme climatic conditions 被引量:1
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作者 J. MARTINEZ S. MERINO 《Current Zoology》 SCIE CAS CSCD 北大核心 2011年第3期390-405,共16页
The effect that climatic changes can exert on parasitic interactions represents a multifactor problem whose results are difficult to predict. The actual impact of changes will depend on their magnitude and the physiol... The effect that climatic changes can exert on parasitic interactions represents a multifactor problem whose results are difficult to predict. The actual impact of changes will depend on their magnitude and the physiological tolerance of affected organisms. When the change is considered extreme (i.e. unusual weather events that are at the extremes of the historical distribution for a given area), the probability of an alteration in an organisms' homeostasis increases dramatically. However, factors determining the altered dynamics of host-parasite interactions due to an extreme change are the same as those acting in response to changes of lower magnitude. Only a deep knowledge of these factors will help to produce more accurate predictive models for the effects of extreme changes on parasitic interactions. Extreme environmental conditions may affect pathogens directly when they include free-living stages in their life-cycles and indirectly through reduced resource availability for hosts and thus reduced ability to produce efficient anti-parasite defenses, or by effects on host density affecting transmission dynamics of diseases or the frequency of intraspecific contact. What are the consequences for host-parasite interactions? Here we summarize the present knowledge on three principal factors in determining host-parasite associations; biodiversity, population density and immunocompetence In addition, we analyzed examples of the effects of environmental alteration of anthropogenic origin on parasitic systems because the effects are analogous to that exerted by an extreme climatic change [Current Zoology 57 (3): 390405, 2011]. 展开更多
关键词 BIODIVERSITY Climate change IMMUNOCOMPETENCE Parasite-host interactions POLLUTION Population density
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Acupuncture in Preterm Babies during Minor Painful Procedures 被引量:1
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作者 Ayse Ecevit Deniz Anuk Ince +2 位作者 Aylin Tarcan Mehmet Tugrul Cabioglu Abdullah Kurt 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2011年第4期308-310,共3页
Objective: To evaluate analgesic effects of acupuncture in preterm neonates during minor painful procedures. Methods: Ten preterm neonates requiring heel prick for blood gas analysis were enrolled in the study, which ... Objective: To evaluate analgesic effects of acupuncture in preterm neonates during minor painful procedures. Methods: Ten preterm neonates requiring heel prick for blood gas analysis were enrolled in the study, which had a crossover design. Oxygen saturation, systolic and diastolic blood pressure, respiratory rate, heart rate, and crying duration were recorded before and after heel prick. Babies were given expressed breast milk before each procedure. Patients were randomly assigned to receive acupuncture or not, and the groups were crossed over on the following day, so that patients who had received acupuncture received only breast milk, and the previous breast milk only group received both acupuncture and breast milk. The neonatal infant pain scale (NIPS) was used for pain evaluation. Results: Crying duration and NIPS pain scores during heel prick were lower in the neonates who had received acupuncture. Conclusion: Acupuncture is an effective method for the treatment of pain in neonates. 展开更多
关键词 acupuncture neonatal pain non-pharmacological treatment
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Lower Carboniferous carbon isotope stratigraphy in South China: Implications for the Late Paleozoic glaciation 被引量:9
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作者 QIE WenKun ZHANG XiongHua +1 位作者 DU YuanSheng ZHANG Yang 《Science China Earth Sciences》 SCIE EI CAS 2011年第1期84-92,共9页
Studies on carbon isotopes of bulk carbonates from Longan and Baping sections of Lower Carboniferous in Guangxi of China show that the stable carbon isotope compositions in carbonate rocks of the isolated platform and... Studies on carbon isotopes of bulk carbonates from Longan and Baping sections of Lower Carboniferous in Guangxi of China show that the stable carbon isotope compositions in carbonate rocks of the isolated platform and deep slope facies were resistant to the influence of early meteoric diagenesis and late burial diagenesis. Three major positive carbon isotope excursions have been recognized in Lower Carboniferous in South China. The first major positive δ3C shift of 4.19‰ occurred in the middle part of Siphonodella isosticha-upper Siphonodella crenulata zone (Tournaisian); the second with an amplitude of 4.65‰ occurred near the Tournaisian/Visean boundary; and the third of 2.23‰ in the lower part of Gnathodus bollandensis zone. The three positive shifts of δ3C can be correlated with global carbon isotope excursions and are consistent with the fall in global sea level, indicating that abundant organic carbon burial, lowering of atmospheric CO2, and glaciation may have occurred during these time intervals. 展开更多
关键词 CARBONIFEROUS GLACIATION carbon isotope GUANGXI South China
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Climate change and infectious diseases of wildlife: Altered interactions between pathogens, vectors and hosts
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作者 Milena GALLANA Marie-Pierre RYSER-DEGIORGIS Thomas WAHLI Helmut SEGNER 《Current Zoology》 SCIE CAS CSCD 2013年第3期427-437,共11页
Infectious diseases result from the interactions of host, pathogens, and, in the case of vector-borne diseases, also vec- tors. The interactions involve physiological and ecological mechanisms and they have evolved un... Infectious diseases result from the interactions of host, pathogens, and, in the case of vector-borne diseases, also vec- tors. The interactions involve physiological and ecological mechanisms and they have evolved under a given set of environmental conditions. Environmental change, therefore, will alter host-pathogen-vector interactions and, consequently, the distribution, in- tensity, and dynamics of infectious diseases. Here, we review how climate change may impact infectious diseases of aquatic and terrestrial wildlife. Climate change can have direct impacts on distribution, life cycle, and physiological status of hosts, pathogens and vectors. While a change in either host, pathogen or vector does not necessarily translate into an alteration of the disease, it is the impact of climate change on the interactions between the disease components which is particularly critical for altered disease risks. Finally, climate factors can modulate disease through modifying the ecological networks host-pathogen-vector systems are belonging to, and climate change can combine with other environmental stressors to induce cumulative effects on infectious dis- eases. Overall, the influence of climate change on infectious diseases involves different mechanisms, it can be modulated by phenotypic acclimation and/or genotypic adaptation, it depends on the ecological context of the host-pathogen-vector interactions, and it can be modulated by impacts of other stressors. As a consequence of this complexity, non-linear responses of disease sys- tems under climate change are to be expected. To improve predictions on climate change impacts on infectious disease, we sug- gest that more emphasis should be given to the integration of biomedical and ecological research for studying both the physio- logical and ecological mechanisms which mediate climate change impacts on disease, and to the development of harmonized methods and approaches to obtain more comparable results, as this would support the discrimination of case-specific versus gen- eral mechanisms . 展开更多
关键词 Climate change WILDLIFE Disease Host Pathogen Vector Species interactions
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