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51.
许锦  席斌斌  蒋宏 《岩矿测试》2016,35(4):389-396
油气包裹体广泛应用于油气成藏研究,但油气包裹体能否继承母油荧光及地球化学特征等,尚缺乏直接的实验证据。本文在开放体系下用NaCl挥发结晶法对一轻质原油进行合成烃类包裹体实验,通过镜下观察和激光剥蚀色谱-质谱技术分析合成的烃包裹体和母油的荧光特征、成分特征及地化特征,研究两者的异同点。结果表明,在NaCl合成烃类包裹体中共发现三种相态的包裹体:纯液相烃包裹体、气液两相烃包裹体和气油水三相包裹体;共有绿黄色荧光、蓝色荧光两种不同颜色的荧光特征。相对于母油,合成包裹体的饱和烃和芳烃类化合物中的轻质组分含量较低,可以推测在母油被捕获成为包裹体的过程中,不同的化学成分存在差异性捕获。但合成包裹体的Pr/Ph等地化参数和不同系列化合物相对含量与母油相差不大,能很好地反映母油的沉积环境等地化特征。因此,包裹体成分信息可以应用于油源对比分析。  相似文献   
52.
徐国栋  金斌  葛建华  董俊  程江 《岩矿测试》2016,35(2):134-137
目前采用酸溶分解试样,以硫脲或磷酸氢二铵为基体改进剂,应用石墨炉原子吸收光谱法(GFAAS)可以直接测定各类地质样品中的痕量银;但应用于测定碳酸盐岩中的痕量银时,基体元素钙镁会产生干扰,同时影响石墨管的使用寿命。本文采用盐酸-硝酸-氢氟酸-高氯酸四酸溶样,硝酸提取,以草酸铵(45.5 g/L)作基体改进剂,试液中的钙镁与草酸铵快速反应生成白色沉淀物而分离,并形成了具有挥发性的铵盐介质环境,可显著提高石墨炉的灰化温度进一步除去铵盐介质,从而消除了基体元素的各种影响。本方法操作简单,经国家标准物质验证,其测定值与标准值的相对偏差均小于10%,检出限为0.010μg/g,精密度(RSD,n=12)小于1.0%。本方法不仅分离了干扰基体,而且比前人采用的一米光栅发射光谱法的检出限(0.04μg/g)更低。  相似文献   
53.
This paper presents a set of energy and resource intensive scenarios based on the concept of Shared Socio-Economic Pathways (SSPs). The scenario family is characterized by rapid and fossil-fueled development with high socio-economic challenges to mitigation and low socio-economic challenges to adaptation (SSP5). A special focus is placed on the SSP5 marker scenario developed by the REMIND-MAgPIE integrated assessment modeling framework. The SSP5 baseline scenarios exhibit very high levels of fossil fuel use, up to a doubling of global food demand, and up to a tripling of energy demand and greenhouse gas emissions over the course of the century, marking the upper end of the scenario literature in several dimensions. These scenarios are currently the only SSP scenarios that result in a radiative forcing pathway as high as the highest Representative Concentration Pathway (RCP8.5). This paper further investigates the direct impact of mitigation policies on the SSP5 energy, land and emissions dynamics confirming high socio-economic challenges to mitigation in SSP5. Nonetheless, mitigation policies reaching climate forcing levels as low as in the lowest Representative Concentration Pathway (RCP2.6) are accessible in SSP5. The SSP5 scenarios presented in this paper aim to provide useful reference points for future climate change, climate impact, adaption and mitigation analysis, and broader questions of sustainable development.  相似文献   
54.
Degraded fuel oils are generally used in marine power plants for economic purposes, so as to reduce operating expenses. These marine fuel oils commonly contain various oxides or sulfide compounds of metallic elements in the fuel ash, and affect the combustion and emission characteristics of marine power plants to different extents. Moreover, marine power plants are more often operated in a highly humid environment. As a result the emission and burning process may also be altered by the various humidity level of the inlet air. The effects of potassium sulfide in marine diesel on the combustion and emission characteristics of marine furnaces under varying levels of relative humidity of inlet air were experimentally investigated in this study. A cylindrical industrial furnace made of AISI 316 stainless steel, and an automatic oil-fired burner were used for the emission characteristics measurements and observation. A mechanically homogenizing machine was used to stir potassium sulfide (K2SO4) powder and marine diesel with a preset K2SO4 concentration. The relative humidity of the inlet air and temperature were adjusted to their assigned values by a large-size air conditioner before being pumped into the burner. The marine diesel oil mixture was atomized by the inlet air consequently ignited by an electrode and then burned within the horizontal furnace. There were eight rectangular slots cut in the upper portion of the furnace wall so that the probes of a gas analyzer and a thermocouple could be inserted into radial positions in the cylindrical furnace. The concentrations of gas emission and burning gas temperature and the combustion efficiency were analyzed. The experimental results show that the burning gas temperature, carbon dioxide emission and combustion efficiency decreased when the concentrations of excess air and oxygen emission increased with the addition of potassium sulfide in the marine diesel fuel. This is primarily attributed to the fact that the sulfide of an alkali compound such as K2SO4 may suppress the oxidation reaction process, leading to inferior combustion characteristics.  相似文献   
55.
本文研究了快速测定石墨灰分中14种杂质元素Al,Ca,Cd,Co,Cr,Cu,Fe,Mg,Mn,Mo,Ni,Ti,V,Zn的分析方法,以满足提纯石墨研究工作对快速了解石墨提纯效果的要求.依据测定样品中各元素的含量情况,实验选择14种元素的分析线.运用ICP-AES谱线轮廓图功能,消除常量元素产生的基体背景干扰.运用干扰系数法进行测定结果校正,并对ICP-AES测定灰分中14种元素的检出线、精密度、准确度进行了测定.结果显示,本方法分析石墨灰分中杂质元素能够满足提纯石墨研究工作的要求.  相似文献   
56.
Marine power plants are frequently operated under varying atmospheric air temperature and humidity conditions. The effects of inlet air temperatures and humidity of marine furnaces such as incinerators and boilers thus attract much research interest. An industrial furnace incorporated with an automatic burner was employed to experimentally investigate the influences of the inlet air temperature and humidity on the emission characteristics. The inlet air humidity and temperature were adjusted using an air-conditioning machine to preset values before being admitted into the burner. ASTM No. 2D diesel oil was atomized, mixed with the inlet air and burned inside the industrial furnace. Eight small rectangular slots were cut on the upper side of the furnace to allow gas analyzer and thermocouple probes to be inserted into the furnace center to measure the axial variations in the gas temperature, burning efficiency and burning gas compositions such as NOx, SO2, CO. The experimental results show that the O2 and NOx emission concentrations decreased while the CO2 emission concentration and burning efficiency increased with either increasing inlet air humidity or temperature.  相似文献   
57.
配额拍卖机制在碳市场中具有重要作用。文中在综述配额拍卖机制研究进展的基础上,重点回顾拍卖机制在欧盟、美国加州和澳大利亚等具有代表性的国际碳市场中的应用情况,结合国内试点碳市场的运行情况,分析不同地区碳市场中拍卖机制的效果。研究认为,国际碳市场拍卖机制设计较为完善,在实际应用中效果良好,起到了增强市场流动性的作用,国内各试点碳市场拍卖机制仍处于探索阶段。文中从拍卖机制的要素设计、平台建设、所得资金管理等方面对全国统一碳市场配额拍卖机制设计提出建议,为全国碳市场中拍卖机制的建设提供参考。  相似文献   
58.
A new airborne remote sensing approach to estimate an upper limit of the direct sea-air methane emission flux was applied over the 22/4b blowout site located at N57.92°, E1.63° in the North Sea. Passive remote sensing data using sunglint/sunglitter geometry were collected during instrumental tests with the Methane Airborne MAPper – MAMAP – instrument installed aboard the Alfred Wegener Institute (AWI) Polar-5 aircraft on 3. June 2011. MAMAP is a passive short wave infrared (SWIR) remote sensing spectrometer for airborne measurements and retrieval of the atmospheric column-averaged dry air mole fractions of methane (XCH4) and carbon dioxide (XCO2). In addition to MAMAP a fast CH4 in-situ analyzer (Los-Gatos Research Inc. RMT-200), two 5-hole turbulence probes and the Polar-5 basic sensor suite comprising different temperature, pressure, humidity and camera sensors were installed aboard the aircraft. The collected MAMAP remote sensing data acquired in the vicinity of the 22/4b blowout site showed no detectable increase in the derived XCH4 (with respect to the atmospheric background). Based on the absence of a detectable XCH4 column increase, an approximate top-down upper-limit for the direct atmospheric 22/4b blowout CH4 emissions from the main bubble plume of less than 10 ktCH4/yr has been derived. The constraint has been determined by comparing XCH4 information derived by the remote sensing measurements with results obtained from a Gaussian plume forward model simulation taking into account the actual flight track, the instrument sensitivity and measurement geometry, as well as the prevailing atmospheric conditions.  相似文献   
59.
Kye Hwa Yoo   《New Astronomy》2010,15(2):215-226
The symbiotic variable star CH Cygni went on the deepest minimum phase in December 2006. A high-resolution spectrum of CH Cygni obtained at the Bohyunsan Optical Astronomy Observatory (BOAO) on November 2, 2006, is reported. The spectrum of CH Cygni obtained at the BOAO was calibrated on a scale of an absolute-flux density. Emission lines of H I, [O III], [N II], and [S II] were strong, with several components, and Ca II, H, and K lines had P-Cygni profiles. Removal of the spectrum of the underlying M-type star from the CH Cygni spectrum was completed to obtain the true emission profiles. The radial velocities of all emission and absorption lines were measured. Some of the observed lines were also deconvoluted using multi-Gaussian functions to find the relationship between line shapes and the corresponding sources of these lines. The results obtained are discussed in terms of an accretion disk around the hot star, and in non-spherically extended nebular regions.  相似文献   
60.
煤中氟的研究进展   总被引:3,自引:0,他引:3  
在全面综合国内外研究文献的基础上,分析了煤中氟的含量、分布规律、赋存状态以及燃烧释放规律等方面的研究进展和存在的问题。我国煤中氟的研究总体上说滞后于煤中其它某些微量元素(如砷、硒、汞等)的研究。进一步深入研究煤中氟+K313的分布规律、赋存状态、来源及迁移转化规律,是今后煤中氟研究的重点。  相似文献   
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