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121.
Sampling of fluids in deep boreholes is challenging because of the necessity of minimizing external contamination and maintaining sample integrity during recovery. The U‐tube sampling methodology was developed to collect large volume, multiphase samples at in situ pressures. As a permanent or semi‐permanent installation, the U‐tube can be used for rapidly acquiring multiple samples or it may be installed for long‐term monitoring applications. The U‐tube was first deployed in Liberty County, TX to monitor crosswell CO2 injection as part of the Frio CO2 sequestration experiment. Analysis of gases (dissolved or separate phase) was performed in the field using a quadrupole mass spectrometer, which served as the basis for determining the arrival of the CO2 plume. The presence of oxygen and argon in elevated concentrations, along with reduced methane concentration, indicates sample alteration caused by the introduction of surface fluids during borehole completion. Despite producing the well to eliminate non‐native fluids, measurements demonstrate that contamination persists until the immiscible CO2 injection swept formation fluid into the observation wellbore. 相似文献
122.
新世纪以来中德世界城市全球化模式对比分析 总被引:1,自引:0,他引:1
城市全球化逐渐从跨国资本主导下的单一化模式向国家特性作用下的多元化发展转变。本文对比分析了新世纪以来中国和德国世界城市全球化的过程、格局、规模、产业和动力,揭示出国家特性作用下的差异化城市全球化模式。结果表明:①中国城市全球化起步较晚但发展迅速。②中国世界城市呈现“大分散,小集聚”的格局,全球化要素具有分散化趋势。③中国世界城市经济的总量大但平均规模小,企业总部集中分布于北京。④中国世界城市一、二次产业产值比重大,金融地产、社会公共服务业和总部经济发展滞后。⑤中国城市全球化是国家政府主导下依托跨国投资生产并出口初级工业品的被动全球化,未来须发挥高级生产者服务、研发服务和社会服务的动力作用。 相似文献
123.
Environmental archaeology methods can uncover both house lot organization and economic adaptation practices when applied systematically in conjunction with traditional archaeological research. This is the first study to employ both phytolith analysis and soil chemistry to interpret activity areas on an archaeological site. The patterning in the phytolith and soil chemistry analyses from the site of Rich Neck Plantation, Williamsburg, Virginia, reveals a set of six activity areas in and around the 17th century house lot, demonstrating a degree of economic diversification generally attributed only to 18th century colonial economic and social transformations. 相似文献
124.
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126.
郑先兴 《世界古典文明史杂志》2008,(3)
汉代西王母崇拜充分表现在汉砖、石、镜及摇钱神树上的西王母艺术图像中,其发展经过了“长寿之偶像”、“神的救赎”、“神的创世”3个阶段。汉代人所以崇信西王母,一是基于现实生活的需要,即祈福成仙;二是基于精神的需要,即试图冲破制度的束缚以寻求情欲的满足和自身价值的实现。 相似文献
127.
从1940年开始到1941年,国民党统治区爆发了一场空前规模的粮食危机.粮食缺乏和粮价高涨是这场危机的主要表现.粮食危机的出现原因主要是由于国统区粮食产量的大量减产、生产成本和销售成本的增加、通货膨胀和投机者囤积居奇所致. 相似文献
128.
John Kantner 《Journal of Archaeological Research》2008,16(1):37-81
In the 1970s and 1980s, regional analysis was an influential part of archaeological research, providing a discrete set of
geographical tools inspired by a processual epistemological and interpretive perspective. With the advent of new technologies,
new methods, and new paradigms, archaeological research on regional space has undergone significant changes. This article
reviews the state of regional archaeology, beginning with a consideration of its history and a discussion of the fundamental
issues facing regional investigations before focusing on developments over the last several years. On one hand, the diversification
of archaeological theory has created new paradigms for thinking about human relationships with one another and with the physical
environment across regional space; in this regard, historical ecology, landscape archaeology, and evolutionary theory have
been particularly influential in recent years. This has led to a corresponding diversification of the traditional methods
of regional analysis. Most notably, the advent of powerful digital technologies has introduced new tools, especially those
from the geographic information sciences, that build on the quantitative methods of past approaches. The investigation of
regional data is no longer based on a discrete toolkit of simple mathematical and graphical procedures for representing spatial
relationships. Instead, regional archaeology has matured into a diversity of multiscalar spatial and geostatistical techniques
that inform many areas of archaeological inquiry. 相似文献
129.
明代贵州得到前所未有的开发,中央政府既有大同思想,对贵州各民族施行怀柔政策,希望天下归心,形成四海一家的气象,又有明显的等级观念和大汉族主义情结,坚持汉族正统地位,“明华夏之别”、“谨夷汉之防”。外来移民到贵州求生存谋发展而又疏高贵州,生活在贵州却又有着强烈的故乡情怀;依托贵州而又有傲慢之态,与贵州少数民族相依相偎而又心存排斥。贵州土司迫于政治形势接受开发,却又竭力维护既得利益;下层广大民众热心学习中原封建文化和生产技术,但是在基本生存权力得不到保障时被迫反抗。矛盾的心理一方面推动着贵州的开发进程,另一方面又使开发出现停滞或破坏。 相似文献
130.
Gas chromatography (GC), GC-mass spectrometry (GC-MS) and GC-combustion-isotope ratio MS (GC-C-IRMS) analyses of absorbed and surface lipid residues preserved in potsherds were used to explore the extent of pig product processing exploitation in the later British Neolithic Grooved Ware tradition. Assessments were made regarding whether porcine lipids were associated with specific Grooved Ware traits, i.e. decoration, substyle, geographical area and type of site. Two hundred and twenty-two Grooved Ware potsherds were analysed, 70% of which contained lipid concentrations considered significant (>5 μg g−1). All the lipid residues were dominated by animal fats, although plant and beeswax were also detected in a small number of extracts. δ13C values of the major fatty acid components of degraded animal fats (C16:0 and C18:0) were determined for 126 extracts and used to assign ruminant or porcine origins to the residues; 16% of these were found to have a predominantly porcine isotope signature. Statistical associations with pig exploitation were shown to exist with substyle, geographical area and site type, whereas, no relationship was seen between decoration and the type of commodity processed. Intact triacylglycerols were preserved in 19% of the sherds; half of these had distributions consistent with the identifications based on δ13C values, the remainder differed either due to the presence of mixed commodities or because lower molecular weight homologues had been lost due to degradation. In addition to the detection of pig exploitation, results from lipid residue analysis showed a good correlation with faunal assemblages, suggesting that stable isotope analysis may be used as a proxy for animal exploitation at sites where bones have not survived. 相似文献