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171.
介绍了天然气水合物的遥感探测方法,即:首先选择适当的ETM+、ASTER以及Quickbird等遥感图像,分析可见光、短波红外、热红外波段的影像特征,反演地表温度;然后结合野外调查和前人资料,寻找天然气水合物的直接和间接遥感解译标志,进行遥感解译。研究结果表明,青藏高原天然气远景区出现的几种遥感解译标志包括:地表上空高温异常(尤其是水体上空)、泥火山、沼泽地水体中大量气泡和棕黄色沉淀物,以及碳酸盐化、粘土化等指示信息。本研究为进一步开展大规模天然气水合物遥感调查和圈定靶区提供了基础方法。 相似文献
172.
南海南部陆缘蕴藏着非常丰富的油气资源。为了解南海南部陆缘流体活动系统以及与油气藏之间的关系,以高精度2D地震资料为基础,对南海南部陆缘流体活动系统的类型、地震反射特征、以及对油气成藏的意义开展了研究。在南海南部陆缘发现了多种流体活动系统,包括:泥底辟/泥火山、气烟囱、管状通道、与构造断层相关的流体活动系统。这些流体活动系统具有不同的地震反射特征,常常出现含气强振幅异常带、弱振幅杂乱反射带以及"下拉"或者"上拱"地震反射形态等流体活动系统的标志特征。流体活动系统受到构造运动和沉积因素的影响,并且与深部高温高压塑性流体密切相关,流体活动系统优先发育在地层薄弱部位。流体活动系统及所伴生的断裂和裂隙常常作为油气富集区的运输通道;并且流体活动系统所运移的强溶蚀性流体和深部热液流体有利于油气储层的形成,特别是对于碳酸盐岩储层的改造尤为明显。因此,流体活动系统不仅能作为油气运移通道,也可以改善储层,对油气成藏具有重要意义。 相似文献
173.
虾蟹混养塘中WSSV对三疣梭子蟹(Portunus trituberculatus)致死效应的定量研究 总被引:1,自引:0,他引:1
采用实时荧光定量PCR法,在对白斑综合症多发的虾蟹混养塘内三疣梭子蟹体内病毒含量进行定量跟踪检测的基础上,结合电子显微镜及病理切片,对室内经口服、注射两种回感模式处理已感染白斑综合症病毒的濒死三疣梭子蟹体内病毒含量进行实验验证,并观察其体内主要器官组织的病理改变。结果表明,受白斑综合症病毒感染的三疣梭子蟹存活与死亡取决于蟹体内病毒含量,当病毒含量≥109拷贝/ml时均进入濒死或死亡阶段,其主要器官组织均有明显的病理改变。 相似文献
174.
Temperature treatment to inhibit extrusion of the polar body of the egg was first used on a lower crustacean,Artemia salina (Gross, 1932), and then was used for inducing triploids of amphibian (Frankhauser and Griffiths, 1939), fish (Svardson, 1945),
and mammal (Beatly and Fishchberg, 1949).
So far, induction of triploidy has been extensively used to obtain sterile or quick-growth individuals in fish (Swarup, 1956;
Lincoln, and Scott, 1983 and Thorgaard, 1986) and mollusk (Stanley et al., 1984), but similar work has not been reported on
crab, a higher crustancean. 相似文献
175.
The paper presents the results of multidisciplinary seismic surveys carried out by refraction and reflection methods for compressional and shear waves on Yuzhno-Sakhalinsk mud volcano. A large extinct (approximately 60–70 years ago) volcano was identified near the active volcano, and its structure was studied. It was found that the recognized intermediate fluid-bearing chambers correlate with the distinguished tectonic dislocations. A supposition was made that the mud volcanism is sequentially developed in the northeastern direction and related to the modern tectonics of the Central Sakhalin Fault. 相似文献
176.
Vasile Muntean Radu Crisan Daniela Paşca Stefan Kiss Mihail Drăgan-Bularda 《International Journal of Salt Lake Research》1996,5(1):35-44
Sediments of 56 salt lakes from Romania were studied enzymologically. The following 7 enzymatic and nonenzymatic catalytic activities have been measured: phosphatase, H2O2-splitting in nonautoclaved (catalase) and autoclaved samples, TTC reduction in nonautoclaved (dehydrogenase) and autoclaved samples, without or with glucose addition. A formula is proposed for the evaluation of the enzymatic potential of salt lake sediments or other habitats. A hierarchy of the studied lakes has been established on the basis of the enzymatic potential of their sediments expressed as enzymatic indicator. 相似文献
177.
A method for estimating microporosity of fine‐grained sediments and sedimentary rocks via scanning electron microscope image analysis 下载免费PDF全文
This study presents a method of two‐dimensional scanning electron microscope image analysis that directly quantifies microporosity abundance in clay‐rich, fine‐grained sediments. The method is novel in that it is specifically designed to circumvent the challenge to porosity quantification posed by mineral surface charging and topographical artifacts created during Ar‐ion cross‐section polishing. It utilizes the finding that differences in circularity values can be used to distinguish micropores from blemishes in a thresholded image. This method is powerful because it is fast and provides a direct microporosity estimation technique to augment or replace experimental data. The pore size range to which the method is applicable is clear and can be selected depending on the application of the analysis. When used appropriately, the method can be implemented on microporous sediments and sedimentary rock in general. The method is developed using marine muds of Pliocene and Miocene ages from the Nankai margin (burial depths from approximately 200 to 1100 m). The close match between imaging‐derived microporosity and bulk N2 microporosity measurements shows that porosity in these young and relatively shallowly buried sediments is dominated by pores of sizes that can be imaged by scanning electron microscopy. In Kumano, forearc basin sediments of the Nankai Trough, results of this method show a significant increase in microporosity with burial depth, probably due to microporosity preservation during compaction and possibly early volcanic ash diagenesis. 相似文献
178.
内源酶是三疣梭子蟹(Portunus trituberculatus)体内重要的酶,往往会导致梭子蟹死后肌肉组织迅速软化,严重影响了蟹肉的贮藏品质。为了探明该酶的基本特性,本试验从三疣梭子蟹肝胰腺中提取了粗酶,优化了提取方法,并对其部分酶学性质进行初步研究。结果表明:三疣梭子蟹肝胰腺内源酶最佳浸提时间段为4~12 h,酶比活显著高于0~4 h和12~14 h;以酪蛋白为水解底物,内源酶作用最适温度为65℃、最适p H范围为7.0~8.0;丝氨酸蛋白酶特异性抑制剂,包括大豆胰蛋白酶抑制剂(SBTI)和苯甲基磺酰氟(PMSF),对内源酶活力的相对抑制率分别为100%、70.46%±6.27%,显著高于其他抑制剂的相对抑制率,推测丝氨酸蛋白酶为主要内源酶;在硫酸铵分级沉淀中,分别以酪蛋白和Boc-Phe-Ser-Arg-MCA为底物,前者最适盐析浓度为0~70%,后者为30%~70%,酶比活显著高于其他盐浓度;当硫酸铵浓度为40%~60%时,盐析蛋白质含量、粗酶酶活和丝氨酸蛋白酶活均显著高于其他盐浓度。 相似文献
179.
180.
The life cycle of the semiterrestrial mangrove crab Ucides cordatus includes pelagic larvae that are released into estuarine waters during the wet season and who may thus encounter potentially stressful low and variable salinity conditions. The effect of salinity on the survival of the zoea larvae, the number of zoeal stages and the duration of development from hatching to megalopa was experimentally studied by rearing larvae from the Caeté estuary, Northern Brazil, in seven salinity treatments (0, 5, 10, 15, 20, 25, and 30). For a better interpretation of the laboratory results, estuarine salinities were measured over five consecutive years during the species' reproductive season. The survival of the zoea larvae varied significantly with salinity, while the number of stages and the duration of their development remained constant. Development to megalopa took 20.77 ± 1.57 days and comprised five zoeal stages with ZI and ZII being euryhaline and later stages stenohaline. The newly hatched larvae stayed alive for up to 6 days in freshwater (average 4.32 ± 0.82 days), but did not moult to the second zoeal stage. ZII larvae first occurred from salinity 5 onwards and later zoeal stages at all tested salinities ≥10. However, the larvae only survived to megalopa at salinities ≥15, with highest numbers at salinity 30 (72%) and lowest at 15 (16%). Lethal salinities ≤10 occurred frequently in the estuary during the reproductive season. This suggests a need for larval export to offshore and thus more saline waters to allow for significant larval survival and maintenance of viable populations of this commercially important species. A regional rather than local approach for management is suggested due to the likelihood of long distance larval dispersal by offshore currents. 相似文献