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Unconventional Natural Gas Accumulations in Stacked Deposits:A Discussion of Upper Paleozoic Coal-Bearing Strata in the East Margin of the Ordos Basin,China 预览
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作者 LI Yong YANG Jianghao +3 位作者 PAN Zhejun MENG Shangzhi WANG Kai NIU Xinlei 《地质学报:英文版》 SCIE CAS CSCD 2019年第1期111-129,共19页
The Upper Paleozoic(Carboniferous to Permian)succession in the east margin of the Ordos Basin in the North China Craton has a potential to contain significant hydrocarbon resources,though attention have been mainly at... The Upper Paleozoic(Carboniferous to Permian)succession in the east margin of the Ordos Basin in the North China Craton has a potential to contain significant hydrocarbon resources,though attention have been mainly attracted for its successful development of coalbed methane(CBM).To improve the previous resource estimates and evaluate the hydrocarbon play possibilities,this study incorporated new discoveries of hydrocarbon units and their stratigraphic relation with source rocks,hydrocarbon migration and trapping configurations.Continuous hydrocarbon accumulation units were identified within the Upper Paleozoic,including the Taiyuan,Shanxi and Xiashihezi formations with great tight gas potential,and the Taiyuan and Shanxi formations also containing shale gas and CBM.Different strata combinations are identified with coal deposition and favour for continuous gas accumulations,including the tidal flat,deltaic and fluvial systems distributed in most of the study areas.Methane was not only generated from the thick coal seams in the Taiyuan and Shanxi formations,but also from shale and dark mudstones.The coal,shale and tight sandstones are proved of remarkable gas content and hydrocarbon indications,and the gas saturation of tight sandstones decreases upward.The stacked deposit combinations vary isochronally in different areas,while the coal seams were developed stably showing good gas sources.Two key stages control the hydrocarbon enrichment,the continuous subsidence from coal forming to Late Triassic and the anomalous paleo-geothermal event happened in Early Cretaceous,as indicated by the fluid inclusions evidence.Extensive areas show good hydrocarbon development potential presently,and more works should be focused on the evaluation and selection of good reservoir combinations. 展开更多
关键词 coal measure GAS transitional SHALE GAS TIGHT sand GAS three gases eastern ORDOS Basin
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Nitrous oxide emissions from three temperate forest types in the Qinling Mountains,China 预览
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作者 Wei Xue Changhui Peng +5 位作者 Huai Chen Hui Wang Qiuan Zhu Yanzheng Yang Junjun Zhang Wanqin Yang 《林业研究:英文版》 CAS CSCD 2019年第4期1417-1427,共11页
To understand soil N2O fluxes from temperate forests in a climate-sensitive transitional zone,N2O emissions from three temperate forest types(Pinus tabulaeformis,PTT;Pinus armandii,PAT;and Quercus aliena var.acuteserr... To understand soil N2O fluxes from temperate forests in a climate-sensitive transitional zone,N2O emissions from three temperate forest types(Pinus tabulaeformis,PTT;Pinus armandii,PAT;and Quercus aliena var.acuteserrata,QAT)were monitored using the static closed-chamber method from June 2013 to May 2015 in the Huoditang Forest region of the Qinling Mountains,China.The results showed that these three forest types acted as N2O sources,releasing a mean combined level of 1.35±0.56 kg N2O ha^-1 a^-1,ranging from0.98±0.37 kg N2O ha^-1 a^-1 in PAT to 1.67±0.41 kg N2O ha^-1 a^-1 in QAT.N2O emission fluctuated seasonally,with highest levels during the summer for all three forest types.N2O flux had a significantly positive correlation with soil temperature at a depth of 5 cm or in the water-filled pore space,where the correlation was stronger for temperature than for the water-filled pore space.N2O flux was positively correlated with available soil nitrogen in QAT and PAT.Our results indicate that N2O flux is mainly controlled by soil temperature in the temperate forest in the Qinling Mountains. 展开更多
关键词 FOREST types GREENHOUSE gases N2O FLUXES QINLING MOUNTAINS Soil temperature
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Quality and Emission Analysis of Charcoal from Various Species of Wood Using Improved Carbonization Technologies in Kenya 预览
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作者 Nellie Oduor Emily Kitheka +3 位作者 Celestine Ingutia Nathan Nyamai James Kimwemwe Kevin Juma 《环境科学与工程:A》 2019年第1期16-25,共10页
Biomass energy provides over 70%of the national energy demand in Kenya.Increased demand has contributed to increased environmental degradation through deforestation,contributing significantly to the global emissions o... Biomass energy provides over 70%of the national energy demand in Kenya.Increased demand has contributed to increased environmental degradation through deforestation,contributing significantly to the global emissions of greenhouse gases,loss of habitats,and biodiversity,and increased health risks.Efficient charcoal conversion technologies have been researched and developed.However,no studies have been undertaken to establish the influence of the improved technologies on the quality of charcoal produced and the emission levels of greenhouse gases from each kiln.The study was undertaken(in eastern Kenya)to determine the effect of carbonization technology and tree species on the quality of the charcoal,the emission levels of the kilns,and the energy properties of the charcoal from various selected species.A total of 14 species were sourced for the study and carbonized using the Adams retort,portable metal,improved earth and the traditional earth kilns.The results indicated that Balanites aegyptiaca,Terminalia spinosa,Acacia nilotica and A.tortilis were ranked best indigenous species in terms of calorific values with mean calorific values above 6.0 kcal/g while Prosopis juliflora,Casuarina equistifolia and Eucalyptus camadulensis were the best exotic species with mean kcal/g of 6.430 kcal/g,5.972 kcal/g and 5.633 kcal/g respectively.Analysis of variance on the energy values indicated there was no significant difference in the quality of charcoal produced using the different kilns.The improved earth kiln and the portable metal kiln produced charcoal that was more dense and intact.Charcoal from the preferred indigenous species had also the longest burning time with a mean of 124 minutes compared to 62.4 minutes for the exotics.The highest burning temperature was found in the indigenous species.Results on emission tests were conducted using a portable gas analyzer on the four kiln types.The carbon dioxide emissions were rather high.Methane production in all kilns showed an upward trend at the beginning of the carbonizati 展开更多
关键词 Charcoal production charcoal kilns GREENHOUSE GASES calorific VALUES
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Topological gapless matters in three-dimensional ultracold atomic gases
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作者 Yong Xu 《物理学前沿:英文版》 SCIE CSCD 2019年第4期21-46,共26页
Three-dimensional topological gapless matters with gapless degeneracies protected by a topological invariant defined over a closed manifold in momentum space have attracted considerable interest in various fields rang... Three-dimensional topological gapless matters with gapless degeneracies protected by a topological invariant defined over a closed manifold in momentum space have attracted considerable interest in various fields ranging from condensed matter materials to ultracold atomic gases. As a highly controllable and disorder free system, ultracold atomic gases provide a versatile platform to simulate topological gapless matters. Here, the current progress in studies of topological gapless phenomena in three-dimensional cold atom systems is summarized in the review. It is mainly focused on Weyl points, structured (type-Ⅱ) Weyl points, Dirac points, nodal rings and Weyl exceptional rings in cold atoms. Since interactions in cold atoms can be controlled via Feshbach resonances, the progress in both superfluids for attractive interactions and non-interacting cold atom gases is reviewed. 展开更多
关键词 ULTRACOLD atomic gases WEYL POINTS DIRAC POINTS NODAL RINGS WEYL exceptional RINGS
Enhanced spin-dependent thermopower in a double-quantum-dot sandwiched between two-dimensional electron gases
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作者 迟锋 付振国 +1 位作者 刘黎明 张平 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第10期523-530,共8页
We study the spin-dependent thermopower in a double-quantum-dot(DQD) embedded between the left and right two-dimensional electron gases(2DEGs) in doped quantum wells under an in-plane magnetic field. When the separati... We study the spin-dependent thermopower in a double-quantum-dot(DQD) embedded between the left and right two-dimensional electron gases(2DEGs) in doped quantum wells under an in-plane magnetic field. When the separation between the DQD is smaller than the Fermi wavelength in the 2DEGs, the asymmetry in the dots' energy levels leads to pronounced quantum interference effects characterized by the Dicke line-shape of the conductance, which are sensitive to the properties of the 2DEGs. The magnitude of the thermopower, which denotes the generated voltage in response to an infinitesimal temperature difference between the two 2DEGs under vanishing charge current, will be obviously enhanced by the Dicke effect. The application of the in-plane magnetic field results in the polarization of the spin-up and spin-down conductances and thermopowers, and enables an efficient spin-filter device in addition to a tunable pure spin thermopower in the absence of its charge counterpart. 展开更多
关键词 QUANTUM DOT spin-dependent THERMOPOWER TWO-DIMENSIONAL electron GASES
The impacts of gas impurities on the minimum miscibility pressure of injected CO2-rich gas-crude oil systems and enhanced oil recovery potential
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作者 Abouzar Choubineh Abbas Helalizadeh David A. Wood 《石油科学:英文版》 SCIE CAS CSCD 2019年第1期117-126,共10页
An effective parameter in the miscible-CO2 enhanced oil recovery procedure is the minimum miscibility pressure(MMP)defined as the lowest pressure that the oil in place and the injected gas into reservoir achieve misci... An effective parameter in the miscible-CO2 enhanced oil recovery procedure is the minimum miscibility pressure(MMP)defined as the lowest pressure that the oil in place and the injected gas into reservoir achieve miscibility at a given temperature. Flue gases released from power plants can provide an available source of CO2,which would otherwise be emitted to the atmosphere, for injection into a reservoir. However, the costs related to gas extraction from flue gases is potentially high. Hence, greater understanding the role of impurities in miscibility characteristics between CO2 and reservoir fluids helps to establish which impurities are tolerable and which are not. In this study, we simulate the effects of the impurities nitrogen(N2), methane(C1), ethane(C2) and propane(C3) on CO2 MMP. The simulation results reveal that,as an impurity, nitrogen increases CO2–oil MMP more so than methane. On the other hand, increasing the propane(C3)content can lead to a significant decrease in CO2 MMP, whereas varying the concentrations of ethane(C2) does not have a significant effect on the minimum miscibility pressure of reservoir crude oil and CO2 gas. The novel relationships established are particularly valuable in circumstances where MMP experimental data are not available. 展开更多
关键词 EOR exploiting impure flue gases CO2–crude oil minimum MISCIBILITY pressure(MMP) Impact of GAS IMPURITIES on MMP
Hydrogeochemical and multi-tracer investigations of arsenic-affected aquifers in semi-arid West Africa 预览
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作者 Anja Bretzler Lucien Stolze +5 位作者 Julien Nikiema Franck Lalanne Elaheh Ghadiri Matthias S. Brennwald Massimo Rolle Mario Schirmer 《地学前缘:英文版》 CAS CSCD 2019年第5期1685-1699,共15页
The semi-arid Sahel regions ofWest Africa rely heavily on groundwater from shallow to moderately deep (<100 m b.g.l.) crystalline bedrock aquifers for drinking water production.Groundwater quality may be affected b... The semi-arid Sahel regions ofWest Africa rely heavily on groundwater from shallow to moderately deep (<100 m b.g.l.) crystalline bedrock aquifers for drinking water production.Groundwater quality may be affected by high geogenic arsenic (As) concentrations (>10 μg/L) stemming from the oxidation of sulphide minerals (pyrite,arsenopyrite) in mineralised zones.These aquifers are still little investigated,especially concerning groundwater residence times and the influence of the annual monsoon season on groundwater chemistry.To gain insights on the temporal aspects of As contamination,we have used isotope tracers (noble gases,3H,stable water isotopes (2H,18O)) and performed hydrochemical analyses on groundwater abstracted from tube wells and dug wells in a small study area in southwestern Burkina Faso.Results revealed a great variability in groundwater properties (e.g.redox conditions,As concentrations,water level,residence time) over spatial scales of only a few hundred metres,characteristic of the highly heterogeneous fractured underground.Elevated As levels are found in oxic groundwater of circum-neutral pH and show little relation with any of the measured parameters.Arsenic concentrations are relatively stable over the course of the year,with little effect seen by the monsoon.Groundwater residence time does not seem to have an influence on As concentrations,as elevated As can be found both in groundwater with short (<50 a) and long (>10^3 a) residence times as indicated by 3He/4He ratios spanning three orders of magnitude.These results support the hypothesis that the proximity to mineralised zones is the most crucial factor controlling As concentrations in the observed redox/pH conditions.The existence of very old water portions with residence times >10^3 years already at depths of <50 m b.g.l.is a new finding for the shallow fractured bedrock aquifers of Burkina Faso,suggesting that overexploitation of these relatively low-yielding aquifers may be an issue in the future. 展开更多
关键词 Arsenic Groundwater chemistry WEST AFRICA Fractured aquifers RESIDENCE time NOBLE gases
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粒子群优化BP神经网络在甲烷检测中的应用 预览
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作者 王志芳 王书涛 王贵川 《光子学报》 EI CAS CSCD 北大核心 2019年第4期141-148,共8页
为了准确、快速地检测和预测甲烷气体的浓度,设计了基于红外差分吸收法的甲烷浓度检测系统.为了降低系统部件不稳定带来的影响,检测系统采用双气室结构,气室的输入和输出接口处通过渐变折射率透镜连接到传输光纤,以降低光强的损耗.系统... 为了准确、快速地检测和预测甲烷气体的浓度,设计了基于红外差分吸收法的甲烷浓度检测系统.为了降低系统部件不稳定带来的影响,检测系统采用双气室结构,气室的输入和输出接口处通过渐变折射率透镜连接到传输光纤,以降低光强的损耗.系统对甲烷检测结果的平均误差为0.0075.基于粒子群优化的误差反向传播神经网络算法构建了甲烷预测模型,以浓度在0.2%~2.0%范围内的甲烷气体为研究对象.在样本训练过程中,预测模型的精度达到10-4,实际输出值与期望值线性回归的相关系数为0.9988,最大相对标准偏差为0.248%.实验结果表明,在甲烷浓度预测中,相对于误差反向传播神经网络预测模型,粒子群优化误差反向传播神经网络的预测性能更优. 展开更多
关键词 气体 吸收光谱 误差反向传播 神经网络 甲烷 浓度预测
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All-silica zeolites screening for capture of toxic gases from molecular simulation
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作者 Zhiguo Yan Sai Tang +5 位作者 Xumiao Zhou Li Yang Xingqing Xiao Houyang Chen Yuanhang Qin Wei Sun 《中国化学工程学报:英文版》 SCIE EI CAS CSCD 2019年第1期174-181,共8页
The exhaust gases, including SO2,NH3, H2S, NO2, NO, and CO, are principal air pollutants due to their severe harms to the ecological environment.Zeolites have been considered as good absorbent candidates to capture th... The exhaust gases, including SO2,NH3, H2S, NO2, NO, and CO, are principal air pollutants due to their severe harms to the ecological environment.Zeolites have been considered as good absorbent candidates to capture the six exhaust gases.In this work, we performed grand canonical ensemble Monte Carlo(GCMC) simulations to examine the capability of 95 kinds of all-silica zeolites in the removal of the six toxic gases, and to predict the adsorption isotherms of the six gases on all the zeolites.The simulation results showed that, H2S, NO, NO2, CO and NH3 are well-captured by zeolite structures with accessible surface area of 1600–1800 m^2·g^-1 and pore diameter of 0.6–0.7 nm, such as AFY and PAU, while SO2 is well-adsorbed by zeolites containing larger accessible surface area(1700–2700 m^2·g^-1) and pore diameter(0.7–1.4 nm) at room temperature and an atmospheric pressure.However, at saturated adsorption, zeolites RWY, IRR, JSR, TSC, and ITT are found to exhibit better abilities to capture these gases.Our study provides useful computational insights in choosing and designing zeolite structures with high performance to remove toxic gases for air purification, thereby facilitating the development and application of exhaust gas-processing technology in green industry. 展开更多
关键词 All-silica zeolites TOXIC GASES Adsorption ISOTHERM GCMC simulation
Impurity-induced Shiba bound state in the BCS–BEC crossover regime of two-dimensional Fermi superfluid
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作者 邵思齐 周可召 张志东 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第7期162-167,共6页
For a two-dimensional ultra-cold Fermi superfluid with an effective static magnetic impurity, we theoretically investigated the variation of the Yu–Shiba–Rusinov(YSR) bound state in the Bardeen–Cooper–Schrieffer(B... For a two-dimensional ultra-cold Fermi superfluid with an effective static magnetic impurity, we theoretically investigated the variation of the Yu–Shiba–Rusinov(YSR) bound state in the Bardeen–Cooper–Schrieffer(BCS) to Bose–Einstein condensation(BEC) crossover regime.Within the framework of mean-field theory, analytical results of the YSR bound state energy were obtained as a function of the interaction parameters.First, when the background Fermi superfluid system stays in the weakly interacting BCS regime, we found that the YSR bound state energy is linearly dependent on the gap parameter with its coefficient slightly different from previous results.Second, we discovered re-entrance phenomena for the YSR state and an upper bound of the strength of the interaction between the paired atoms.By carefully analyzing the bound state energy as a function of the interaction parameters, we obtained a phase diagram showing the existence of the YSR state.Finally, we concluded that the re-entrance phenomena and the critical point can be easily experimentally detected through measurement of radio-frequency spectroscopy and density of states using current experimental techniques. 展开更多
关键词 ultra-cold quantum gases BCS–BEC CROSSOVER magnetic IMPURITY Yu–Shiba–Rusinov(YSR) state
Experimental Realization of Degenerate Fermi Gases of 87Sr Atoms with 10 or Two Spin Components
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作者 祁卫 梁明诚 +4 位作者 张涵 魏玉栋 王文伟 王旭杰 张熙博 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第9期18-22,共5页
We report the experimental realization of quantum degenerate Fermi gases of87Sr atoms under controlled 10-and dual-nuclear-spin configurations.Based on laser cooling and evaporative cooling,we achieve an ultracold Fer... We report the experimental realization of quantum degenerate Fermi gases of87Sr atoms under controlled 10-and dual-nuclear-spin configurations.Based on laser cooling and evaporative cooling,we achieve an ultracold Fermi gas of 105 atoms equally distributed over 10 spin states,with a temperature of T/TF = 0.21.We further prepare a dual-spin gas by optically pumping atoms to the mF = 9/2 and mF = 7/2 states and observe a slightly lower T/TF than that for a 10-spin gas under the same trapping condition,showing efficient evaporative cooling under a decreasing number N of spin states(N≥2)despite the increasing importance of Pauli exclusion.Given that rethermalization becomes less efficient with N approaching unity,we evaporatively cool an almost polarized gas to 130 nK.The simple and efficient preparation of ultracold Fermi gases of 87Sr with tunable spin configurations provides a first step towards engineering topological quantum systems. 展开更多
关键词 red Dirac pro Sr ATOMS with 10 or TWO SPIN COMPONENTS Experimental Realization of DEGENERATE FERMI Gases of
Affecting factors and application of the stable hydrogen isotopes of alkane gases 预览
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作者 HUANG Shipeng DUAN Shufu +8 位作者 WANG Zecheng JIANG Qingchun JIANG Hua SU Wang Feng Qingfu HUANG Tongfei YUAN Miao REN Mengyi CHEN Xiaoyue 《石油勘探与开发:英文版》 2019年第3期518-530,共13页
To study the composition, affecting factors of the stable hydrogen isotopes of alkane gases and their application to identification of the natural gas origin and maturities, the chemical and isotopic compositions of 1... To study the composition, affecting factors of the stable hydrogen isotopes of alkane gases and their application to identification of the natural gas origin and maturities, the chemical and isotopic compositions of 118 gas samples of Carboniferous- Permian in the Ordos Basin, and of Triassic in the Sichuan Basin, combined with 68 gas samples from the Sinian and Cambrian reservoirs in the Sichuan Basin, and Ordovician and Siliurian reservoirs of Tarim Basin, are analyzed comprehensively. The following conclusions are obtained:(1) Natural gases in the study area and strata of the Ordos and Sichuan basins are dominated by alkane gases, and the dryness coefficients and maturities of the Carboniferous-Permian gases in the Ordos Basin are higher than the gases in the Triassic Xujiahe Formation of the Sichuan Basin, while the hydrogen isotopes of the latter ones are much enriched in 2H than the former.(2) The δ2HCH4-C1/C2+3 genetic identification diagram of natural gas was drawn, and the diagrams of hydrogen isotopic differences between the heavy alkane gases and methane vs. hydrogen isotopes of alkane gases can also be used in natural gas genetic identification.(3) The δ2HCH4-Ro formulas of coal-formed gas in different areas of the two basins are given, and the δ2HC2H6-δ2HCH4 is a new index for maturity, and the (δ2HC2H6-δ2HCH4)-Ro formula of the coal-formed gas can be used to calculate the maturity of the natural gas.(4) The stable hydrogen isotopes of alkane gases are affected by parent materials in source rocks, maturity, mixing and the aqueous medium conditions, among which the aqueous paleo-salinity is the key factor. To sum up, the hydrogen isotopes of alkane gases are affected by multiple factors, and they are significant to the identification of the origin, and maturity of natural gas, and the water environment during the deposition of source rocks. 展开更多
关键词 ALKANE GASES MATURITY hydrogen isotope gas origin aqueous salinity ORDOS BASIN Sichuan BASIN TARIM BASIN
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Possible origin of inert gases in hydrocarbon reservoir pools of the Zindapir Anticlinorium and its surroundings in the Middle Indus Basin, Pakistan
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作者 Adeel Nazeer Syed Habib Shah +1 位作者 Ghulam Murtaza Sarfraz Hussain Solangi 《大地测量与地球动力学:英文版》 2018年第6期456-473,共18页
The natural gas in several gas fields in Pakistan is associated with varying percentages of inert gases(e.g.,CO2, N2, and H2S). The heating capacity of such natural gas is measured in British thermal units(BTU) in Pak... The natural gas in several gas fields in Pakistan is associated with varying percentages of inert gases(e.g.,CO2, N2, and H2S). The heating capacity of such natural gas is measured in British thermal units(BTU) in Pakistan and is based on the combustion of the natural gases. The study area of this work belongs to the Middle Indus Basin, which also covers some parts of the Sulaiman Foldbelt and the Punjab Platform.Petroleum wells drilled in the study area contain inert gases(mostly CO2 and N2) in varying percentages,which decreases the BTU value of sweet gases and the economic value of the gas reserves.Attempts were made to analyze the varying compositions of inert gases(mostly CO2 and N2) along the deep-seated basement faults in the Zindapir Anticlinorium, eastern Sulaiman Foldbelt, but no specific relation could be established. Similarly, geothermal gradient zones were identified and the distribution of inert gases in these zones was studied, but even so, no well-established relation could be tracked.However, variations in the amounts of inert gases in the Chiltan Limestone of the Rodho Structure and the Afiband Structure point to the generation of in situ inert gases because both wells were drilled on the same anticlinorium and share the same geology, and possibly, the same source rock. Post-accumulation changes probably play an important role in the generation of in situ inert gases in varying concentrations.H2S is also present in some parts of the Indus Basin. Therefore, a brief discussion about the possible origin of the H2S is also included in this paper. 展开更多
关键词 Inert gases Zindapir anticlinorium and HYDROCARBON reservoir POOL Middle Indus BASIN Pakistan
气氛对降膜介质阻挡放电反应器降解甲基橙的影响 预览
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作者 王保伟 彭叶平 +3 位作者 姚淑美 押玉荣 王晓磊 安少锋 《工业水处理》 CSCD 北大核心 2018年第11期35-40,共6页
以偶氮染料甲基橙为对象,研究使用降膜介质阻挡放电(DBD)反应器在不同放电气体(氩气、空气、氧气)下的处理效果。结果表明:氧气作DBD放电气氛时,甲基橙处理效果最佳,氩气次之,空气最差。O3、H2O2、·OH这3种活性氧粒子对于甲基橙氧... 以偶氮染料甲基橙为对象,研究使用降膜介质阻挡放电(DBD)反应器在不同放电气体(氩气、空气、氧气)下的处理效果。结果表明:氧气作DBD放电气氛时,甲基橙处理效果最佳,氩气次之,空气最差。O3、H2O2、·OH这3种活性氧粒子对于甲基橙氧化降解起着至关重要的作用,氧气放电体系内3种活性粒子的含量远高于空气放电体系;氩气放电体系内的H2O2含量最高;空气放电体系还检测到大量的对甲基橙降解不利的NO3-、NO2-。 展开更多
关键词 介质阻挡放电 等离子体 气氛 活性氧粒子 染料废水
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Greenhouse gas emissions from thermal treatment o non-recyclable municipal waste
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作者 Tomas Ferdan Martin Pavlas +2 位作者 Vlastimlr Nevrly Radovan Sompllak Petr Stehllk 《化学科学与工程前沿:英文版》 EI CAS CSCD 2018年第4期815-831,共17页
This paper analyses factors affecting the production of greenhouse gases from the treatment of residual municipal waste.The analysis is conducted so that the environmentally-friendly decision-making criteria may be la... This paper analyses factors affecting the production of greenhouse gases from the treatment of residual municipal waste.The analysis is conducted so that the environmentally-friendly decision-making criteria may be later implemented into an optimisation task,which allocates waste treatment capacities.A simplified method of life cycle assessment is applied to describe environ- mental impact of the allocation.Global warming potential (GWP)is employed as a unit to quantify greenhouse gases (GHG)emissions.The objective is to identify the environmental burdens and credits measured by GWP for the three fundamental methods for treatment of residual waste unsuitable for material recovery.The three methods are waste-to-energy (WTE),landfilling and mechanical-biological treatment (MBT)with subsequent utilization of refuse-derived fuel.The composition of the waste itself and content of fossil-derived carbon and biogenic carbon are important parameters to identify amounts of GHG.In case of WTE,subsequent use of the energy,e.g.,in district heating systems in case of heat,is another important parameter to be considered.GWP function dependant on WTE capacity is introduced.The conclusion of this paper provides an assessment of the potential benefits of the results in optimisation tasks for the planning of overall strategy in waste management. 展开更多
关键词 waste management GREENHOUSE gases global WARMING potential ALLOCATION planning WASTE-TO-ENERGY
Contributions of natural systems and human activity to greenhouse gas emissions 预览
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作者 YUE Xi-Liu GAO Qing-Xian 《气候变化研究进展:英文版》 CSCD 2018年第4期243-252,共10页
In this study, we conducted a literature review of relevant research and then statistically analyzed global greenhouse gas (GHG) emissions from natural systems, including forest fires, oceans, wetlands, permafrost, mu... In this study, we conducted a literature review of relevant research and then statistically analyzed global greenhouse gas (GHG) emissions from natural systems, including forest fires, oceans, wetlands, permafrost, mud volcanoes, volcanoes, and earthquakes. Drawing on the Global Carbon Project (GCP) report, we also summarized the global anthropogenic GHG emissions. We then compared the global annual GHG emissions from natural systems with those generated by human activity. The results indicate that the global annual GHG emissions range approximately between 54.33 and 75.50 Gt CO2-eq, of which natural emissions account for 18.13e39.30 Gt CO2-eq, with the most likely value being approximately 29.07 Gt CO2-eq. According to the GCP report, the global anthropogenic emissions have increased from 22 Gt CO2-eq in 1990 to 36.2 Gt CO2-eq in 2016. The amounts of natural and anthropogenic GHGs emissions are roughly of the same order of magnitude. Anthropogenic emissions account for approximately 55.46% of the total global GHGs emissions (2016 value), i.e., the ratio of natural to anthropogenic emissions is approximately 0.8. In addition, the annual amount of GHGs absorbed by Earth systems (ocean and terrestrial ecosystems) ranges between approximately 14.4 Gt CO2-eq and 26.5 Gt CO2-eq, with natural system GHG emissions and sinks also having roughly the same order of magnitude. This finding indicates that the GHG emissions generated by human activity exert extra pressure on what is otherwise a self-balancing Earth system. 展开更多
关键词 GREENHOUSE gases NATURAL EMISSION ANTHROPOGENIC EMISSION Global EMISSION NATURAL system
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Influence of ship emissions on NOx, SO2, O3 and PM concentrations in a North-Sea harbor in France
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作者 Frederic Ledoux Cloe Rochet +2 位作者 Fabrice Cazier Charles Beaugard Dominique Courcot 《环境科学学报:英文版》 SCIE EI CAS CSCD 2018年第9期56-66,共11页
关键词 港口城市 SO2 NOx 船排 法国 O3 PM10 方海
液化石油气组成准确性因素分析及对策 预览
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作者 赵春梅 姜贵 《石化技术》 CAS 2018年第9期28-29,共2页
本文主要对液化石油气组成测定过程中采样、钢瓶放置方式、水浴温度等影响因素进行分析、探讨,采取相应措施,从而提高试验结果准确性。
关键词 液化石油气 影响因素 对策
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不同艾灸装置内艾燃烧产生细颗粒物及CO、SO2、NO2的观察
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作者 惠鑫 王昊 +8 位作者 和蕊 李天娇 哈略 张瑞 林瑶 李丹 左滢竹 韩丽 赵百孝 《北京中医药大学学报》 CSCD 北大核心 2018年第2期160-164,共5页
目的通过观察在不同艾灸装置内艾燃烧生成细颗粒物(PM_(2.5))和多种气体的排放量,进一步讨论艾灸疗法的安全性。方法试验选取18个同一批次的1 g艾条在3种艾灸装置内燃烧,采用激光粉尘仪、气体检测仪进行检测。18个艾条样品随机分为... 目的通过观察在不同艾灸装置内艾燃烧生成细颗粒物(PM_(2.5))和多种气体的排放量,进一步讨论艾灸疗法的安全性。方法试验选取18个同一批次的1 g艾条在3种艾灸装置内燃烧,采用激光粉尘仪、气体检测仪进行检测。18个艾条样品随机分为自然暴露燃烧组、灸筒燃烧组、灸筒加过滤罩组,每组6个。将艾灸装置在密闭玻璃房内点燃,对其产生的PM_(2.5)质量浓度,CO、SO_2、NO_2摩尔分数进行实时监测,取各项指标的峰值。结果 3组艾条燃烧产生的PM_(2.5)、CO、SO_2有统计学差异,其中灸筒加过滤罩组的PM_(2.5)质量浓度低于灸筒燃烧组和自然暴露燃烧组(P〈0.05),且灸筒加过滤罩组CO、SO_2的摩尔分数显著低于自然暴露燃烧组、灸筒燃烧组(P〈0.05),灸筒加过滤罩组3项指标在3组内均为最低水平。燃烧过程中PM_(2.5)质量浓度峰值为灸筒燃烧组〉自然暴露燃烧组〉灸筒加过滤罩组;CO、SO_2摩尔分数峰值为自然暴露燃烧组〉灸筒燃烧组〉灸筒加过滤罩组。环境中NO_2摩尔分数的监测值并未因艾燃烧而增加。结论不同装置内艾燃烧所产生的PM_(2.5)以及CO、SO_2有差异,艾灸装置加过滤罩可以降低艾灸环境中的PM_(2.5)质量浓度和CO、SO_2摩尔分数,可以避免艾灸过程中产生的烟雾危害。 展开更多
关键词 艾灸装置 灸法 艾烟 细颗粒物 气体 灸法安全性
地层品质因子Q值地震反演问题剖析 预览 被引量:6
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作者 云美厚 党鹏飞 +2 位作者 李伟娜 赵秋芳 聂岩 《石油地球物理勘探》 EI CSCD 北大核心 2017年第1期189-198,共10页
针对目前地层品质因子地震反演及估算研究中存在的5个方面的问题,指出了模型结构、厚度以及模型参数选择的合理性是吸收衰减正演模拟分析的关键。探讨了Q值反演与阻抗反演的异同,明确了连续Q值反演的理论局限性。分析了叠前Q反演与AVO... 针对目前地层品质因子地震反演及估算研究中存在的5个方面的问题,指出了模型结构、厚度以及模型参数选择的合理性是吸收衰减正演模拟分析的关键。探讨了Q值反演与阻抗反演的异同,明确了连续Q值反演的理论局限性。分析了叠前Q反演与AVO反演的差异,揭示了地层吸收衰减导致地震反射波振幅随炮检距增加而减小的内在本质为射线品质因子随炮检距增大而增大,可称之为"QVO效应"。阐明了单一薄层衰减地震响应的可检测性问题,指出了利用薄层衰减地震响应变化来准确反演或估算地层品质因子Q值的困难性和反演估算结果的不确定性。揭示了尽管品质因子比速度对储层含气饱和度更敏感,但并不反映含油气检测更有效,只有二者引起的地震响应强弱变化才是真正意义上含油气检测的敏感性度量指标。与速度相比,单一含气薄层因品质因子Q值降低引起的衰减地震响应变化并不占优势。基于品质因子Q值地震反演结果检测薄储层含油气性具有极大的风险。 展开更多
关键词 品质因子 Q值反演 地震反演 QVO效应 衰减
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