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71.
本文采用材积源生物量法和土壤剖面分析方法,以四川彭州为典型案例,对栽植17年的人工柳杉、杉木、水杉、桦木、桤木、喜树林的碳聚积效应进行了研究.结果表明:不同树种的生物量积累规律为:柳杉>桦木>喜树>水杉>杉木>桤木,每公顷柳杉、桦木、喜树、水杉、杉木、桤木的生物量分别为172t、162t、157t、126t、124t、111t.柳杉的生物量比桦木、喜树、水杉、杉木、桤木增加5.81%、8.72%、26.7%、27.9%、35.5%;不同树种的林分碳贮量为柳杉>桦木>喜树>水杉>杉木>桤木,柳杉、桦木、喜树、水杉、杉木、桤木林分的碳贮量分别为86.0、81.0、7＆5、63.0、62.0、55.5tC/hm2,表明柳杉比其它树种具有更强的生长能力和固碳能力;林下土壤的有机碳含量,在不同土层中的分布规律为:0～10cm>10～30cm>30～50cm>50～70cm,土壤有机碳集中分布于0～50cm土层内;不同树种林下土壤的碳贮量均高于同期的林分碳贮量,表明土壤碳库是林分碳库的补充和延续,且具有更大的固碳潜力. 相似文献
72.
A protocol for easy storage and later expansion of lymphocyte populations is given. Compared with methods using transformed cell lines, the method has a number of advantages for repeated production of cells for the isolation of DNA in amounts sufficient for use in diagnostic DNA technology. 相似文献
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74.
Carbon dioxide capture and sequestration (CCS) in deep geological formations has recently emerged as an important option for reducing greenhouse gas (GHG) emissions, and due to the complexity of the issue, CCS has turned into a multiple‐discipline research area. Environmental isotopes have been used in various CCS projects worldwide for evaluating trapping mechanisms, selecting storage sites, and monitoring for storage safety. Environmental isotopes are found useful in the investigation of many CCS issues and are particularly effective in identifying phase states (free, dissolved, and mineral state), and in quantifying structural, solubility, and mineral trapping forms of CO2. We used published laboratory results to successfully verify different methods for quantifying structural trapping mechanisms. Our results show that, in short time scales, saturation of the formation with free CO2‐phase can be obtained from oxygen isotope measurements on CO2 and/or reservoir brine, and carbon isotope of dissolved inorganic carbon can be used to trace dissolution in brine. Carbon isotopes and other parameters, such as CO2/3He ratio, can also be used to confirm the mineral trapping mechanism in natural gas fields. Environmental isotopes can also be used to distinguish mineralogical composition of formations, and to identify hydrodynamic conditions for site selection in addition to monitor potential CO2 leakage. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
75.
李衍 《中国特种设备安全》2012,(10):34-36
9％镍钢液化天然气储罐制造安装过程中,焊缝检验通常用常规射线照相（RT）进行。本文研讨用相控阵半自动超声检测（AUT）取代射线照相的工艺制定及验证方法。要领分四步：首先带缺陷专用焊接试样的制备;然后相控阵AUT工艺的编制;其次在有已知缺陷的焊接试样上,对AUTT艺作“开放性”验证试验;最后在现场对整个数据采集系统作“封闭性”操作演示和验证评定试验。验证结果表明相控阵AUT取代RT可行可靠,能凸显AUT种种优势。 相似文献
76.
为明确多因素耦合对CO2驱替CH4过程中CH4产出与CO2封存效果的影响特征,开展不同注气温度θ、压力P和煤样含水率W条件下注CO2驱替CH4试验,研究分析不同条件下CH4产出率η和CO2储存率ξ变化特性,基于响应曲面法,构建η和ξ二次回归响应曲面模型,分别考察注气温度A、注气压力B、含水率C对η和ξ的单独影响及各因素间的交互作用。结果表明:η随θ和P增加而增大,随W增大而减小;ξ随P增大而增大,随θ和W增加而减小。影响因素中A、B、C均为η的显著项,B和C是ξ的显著项,一次项对η和ξ影响程度均为C>B>A;交互项对η的影响程度为BC>AC>AB,且AC和BC交互作用显著,AB交互作用不显著;交互项对ξ的影响程度为AB>AC>BC, 且AB和AC交互作用极显著,BC交互作用不显著;4组η和ξ编码区间外试验值与模型预测值平均偏差分别为3.64%、2.605%。 相似文献
77.
Jeffrey M. Bielicki Guillaume Calas Richard S. Middleton Minh Ha‐Duong 《Greenhouse Gases: Science and Technology》2014,4(3):262-277
Planning for the deployment of carbon dioxide capture and storage (CCS), infrastructure must consider numerous uncertainties regarding where and how much CO2 is produced and where captured CO2 can be geologically stored. We used the SimCCS engineering‐economic geospatial optimization models to determine the characteristics of CCS deployment in France and corridors for pipelines that are robust to a priori uncertainty in CO2 production from industrial sources and CO2 storage locations. We found a number of stable routes that are robust to these uncertainties, and thus can provide early options for pipeline planning and rights‐of‐way acquisition. 相似文献
78.
Peter Stigson Simon Haikola Anders Hansson Katarina Buhr 《Greenhouse Gases: Science and Technology》2016,6(2):188-196
As initiatives are taken in Sweden to evaluate the geological potential for carbon dioxide storage in the adjacent Baltic Sea, experiences from elsewhere may provide lessons about perceptions of and potential opposition toward carbon capture and storage (CCS). A comprehensive analysis of storage feasibility needs to include the issue of social acceptance. The knowledge of CCS is low in Sweden however and there are no Swedish CCS projects to learn from. This paper therefore draws on lessons from other large‐scale energy projects that are embedded in similar Baltic Sea contexts to complement lessons on CCS acceptance provided in the literature. The aim of this study is to facilitate an understanding of acceptance of potential future CO2 storage initiatives in the Swedish Baltic Sea region and to analyze what contextual factors are likely to be determinative of the outcome of these and similar projects. The study identifies climate change as one such key contextual factor, which can often be used both to support and oppose a large‐scale energy project. Furthermore, the study finds that there are perceptions of uncertainties regarding the regulatory framework that need to be adressed in order to facilitate the planning of CCS projects in the region. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd 相似文献
79.
《Greenhouse Gases: Science and Technology》2018,8(4):747-761
Carbon dioxide capture and storage (CCS) is an effective technology to reduce carbon dioxide (CO2) emissions in China. In this paper, the authors considered storage opportunities offered by oil reservoirs and deep saline aquifers in the Jiyang Depression, in east China. Based on detailed geological analysis and assessment of CO2 storage suitability, the Dongying Sag and Linyi‐Shanghe areas of the Huimin Sag within the Jiyang Depression appear promising for CO2 storage. Following more detailed characterization, the second and third members of the Shahejie Formation located in these two areas appear the most promising for CO2 storage. Within the areas identified as having potential for storage, 55 primary and 62 secondary recommended storage units were defined, with a total theoretical capacity of 5.02 × 108 tonnes (t) CO2. This represents storage of CO2 emissions from large‐scale sources in the Jiyang Depression for more than 30 years at current emission rates. © 2018 Society of Chemical Industry and John Wiley & Sons, Ltd. 相似文献
80.