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91.
秋茄和榕树叶片中正构烷烃分布和单体化合物δ13C值及其光合作用 总被引:1,自引:0,他引:1
对深圳福田、阳江、海南新竹红树林秋茄Kandelia candel及海口榕树Ficusm icrocarpa叶中类脂物进行萃取,分离出正构烷烃,通过气相色谱(GC)及色谱-质谱(GC MS)分析,测出了正构烷烃的碳数分布和相对含量.气相色谱-稳定同位素比质谱仪(GC-IRMS)测定了正构烷烃单体化合物的稳定同位素组成δ13C.秋茄叶和榕树叶正构烷烃的碳数分布均为C17C33,主要集中在C23-C31(>90%).化合物含量最高为C27的有深圳福田秋茄、海南新竹秋茄、海口榕树,而阳江秋茄为C25.单体化合物的稳定同位素δ13C深圳福田秋茄为-31.42‰-34.48‰,阳江秋茄为-31.69‰-33.62‰,海南新竹秋茄为-30.30‰-33.04‰,海口榕树为-29.92‰33.56‰;平均值分别为-32.95‰、32.67‰、31.67‰、-31.74‰.结果表明,秋茄和陆地植物榕树的光合作用都是通过C3途径,是典型C3植物. 相似文献
92.
采用硫酸铵分部沉淀与凝胶过滤的方法,进行藓羽藻Rubisco的分离研究。结果表明,分离的藓羽藻Rubisco经SDS-聚丙烯酰胺凝胶电泳检测呈两条清晰条带,分别为Rubisco大亚基与小亚基;与菠菜相比,藓羽藻Rubisco大亚基分子量与菠菜基本相同,而小亚基较之稍大一些。藓羽藻Rubisco活力测定结果表明,Rubisco分离过程中用硫酸铵分部沉淀后活力降低许多,分离后活力有所上升,但仍比粗提液活力弱;在Rubisco活力测定过程中,藓羽藻Rubisco的活化温度与其它物种Rubisco活化的温度不同,在低温下活化效果较好。这些结果说明Rubisco的酶活力受硫酸铵的影响而且藓羽藻Rubisco相对陆地高等植物结构不稳定。 相似文献
93.
上新世——早更新世青藏高原北缘隆升的磁性地层学证据 总被引:9,自引:0,他引:9
对新疆叶城剖面西域砾岩及下伏第三纪地层的磁性地层学研究表明 ,西域砾岩的沉积时代为晚上新世至早更新世 ,磁性地层年龄为 3.5至 <1.8Ma。阿图什组沉积于早上新世 ,古地磁年龄为 4 .6~ 3.5 Ma。阿图什组以砂岩和粉砂岩为主夹薄层砾岩 ,为河流相及冲积扇前缘相。西域砾岩以厚层砾岩为主夹风成粉砂岩 ,为典型洪积—冲积扇堆积。西域砾岩的沉积反映了青藏高原北缘晚上新世至早更新世强烈的隆起和剥蚀 相似文献
94.
基于RS与GIS技术的土地利用变更图斑自动识别方法,即"以遥感正射影像图为基础,以地理信息和地物反射光谱为判别依据"的变更信息识别方法,能够尽量避免传统利用遥感影像分类技术进行地物变更识别存在的不足。本文通过对距离算法的改良,有效利用遥感数据的实时性和丰富性,在地理信息系统的支持下,提高了对地物变更地块的识别精度。 相似文献
95.
Floating tephra was deposited together with ice core,snow layer,abyssal sediment,lake sediments,and other geological records.It is of great significance to interpret the impact on the climate change of volcanic eruptions from these geological records.It is the first time that volcanic glass was discovered from the peat of Jinchuan(金川)Maar,Jilin(吉林)Province,China.And it is in situ sediments from a near-source explosive eruption according to particle size analysis and identification results.The tephra were neither from Tianchi(天池)volcano eruptions,Changbai(长白)Mountain,nor from Jinlongdingzi(金龙顶子)volcano about 1 600 aBP eruption,but maybe from an unknown eruption of Longgang(龙岗)volcano group according to their geochemistry and distribution.Geochemical characters of the tephra are similar to those of Jingiongdingzi,which are poor in s.Jica,deficient in alkali,Na20 content is more than K20 content,and are similar to distribution patterns of REE and incompatible elements,which helps to speculate that they originated from the same mantle magma with rare condemnation,and from basaltic explosive eruption of Longgang volcano group.The tephra,from peat with age proved that the eruption possibly happened in 15 BC-26 AD,is one of Longgang volcano group eruption that was not recorded and is earlier than that of Jinglongdingzi about 1 600 aBP eruption.And the sedimentary time of tephra is during the period of low temperature alteration.which may be the influence of eruption toward the local climate according to the correlativity of eruption to local temperature curve of peat cellulose oxygen isotope. 相似文献
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99.
Geochemical characteristics and source analysis of inflow of mine water in Wang’ershan Gold Mine, Shandong 总被引:1,自引:0,他引:1
QIAN Jianping LI Shuangli and CAO Chao Guilin University of Technology Guilin China 《中国地球化学学报》2008,(1)
Through a systematic observation of water level and temperature, and a comprehensive analysis of the data on major/trace elements, nitrite, hydrogen-oxygen isotopes, the conclusion has been drawn that there are two relatively independent groundwater systems (cool water and hot water), and the geochemical indicators of hot/cool waters are described. The cool water system is relatively enriched in Ca2 , Mg2 and HCO3-. Its TDS is relatively low, about 1400–1800 mg/L. The hot water system is relatively enriched in K , Na , Cl- and SO42-. Its TDS is relatively high, about 2200–2300 mg/L. The cool water system is enriched in Ba, Ga, Cd, and the hot water system is enriched in B, Ti, Cr, Ni, Cu, Mo, Rb, and Cs, relatively. Especially, the contents of Rb and Cs in the hot water system are more than five times as high as those in the cool water system. The NO3- contents of cool water discharged from the gold mine are relatively high, and those of hot water are extremely low. The δD and δ18O values follow an increasing order of surface water>mine cool water>mine hot water. The cool water comes mainly from the lateral supply of phreatic water, while the hot water comes mainly from the vertical supply of deeply circulating structure-fracture water. The ratio of cool water over hot water was estimated to be about 1:1 by a water quality model.. 相似文献
100.
LIU Luofu HUO Hong GUO Yongqiang CHEN Lixin LI Shuangwen ZHAO Yande LI Yan WANG Ping CHEN Zhijun 《中国地球化学学报》2008,27(1):1-8
The results presented in this paper indicated that the carbazole-type compounds have high thermal stability and also show stability in oxidation and bio-degradation. This kind of compounds still has high concentrations and a complete distribution in the analyzed dry asphalt samples, showing that they are particularly useful in the study of hydrocarbon migration of the paleo-pools. The difference in the contents of nitrogen compounds in the Silurian dry asphalts from the Awati, Tabei and Tazhong areas is attributed to the difference in the extent of oxidation and (or) bio-degradation for the areas; the Awati and Tabei areas underwent relatively strong oxidation and bio-degradation. During the first stage of hydrocarbon pool formation in the Silurian system in the Tazhong and Tabei areas of the Tarim Basin (at the end of the Silurian period) and at the second stage in the Awati area (in Permian), the hydrocarbons experienced a long-distance migration. 相似文献