110 resultados para Chl


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Seasonal investigations of size-fractionated biomass and production were carried out from February 1992 to May 1993 in Jiaozhou Bay, China. Microplankton assemblages were separated into three fractions: pico-(0.7-2 mu m), nano- (2-20 mu m) and netplankton (20-200 mu m). The biomass was measured as chlorophyll a (Chl a), particulate organic carbon (POC) and particulate organic nitrogen (PON). The production was determined by C-14 and N-15 tracer techniques. The seasonal patterns in biomass, though variable, were characterized by higher values in spring and lower values in autumn and summer (for Chl a only). The seasonal patterns in production, on the other hand, were more clear with higher values occurring in summer and spring, and lower values occurring in autumn and winter. Averaged over the whole study period, the respective proportions of total biomass accounted for by net-, nano- and picoplankton were 26, 45 and 29% for Chl a, 32, 33 and 35% for POC, and 26, 32 and 42% for PON. The contributions to total primary production by net-, nano- and picoplankton were 31, 35 and 34%, respectively. The respective proportions of total NH4+-N uptake accounted for by net-, nano- and picoplankton were 28, 33 and 39% in the daytime, and 10, 29 and 61% at night. The respective contributions to total NO3--N uptake by net-, nano- and picoplankton were 37, 40 and 23% in the daytime, and 13, 23 and 64% at night. Some comprehensive ratios, including C/N biomass ratio, Chl a/C ratio, C uptake/Chl a ratio, C:N uptake ratio and the f-ratio, were also calculated size separately, and their biological and ecological meanings are discussed.

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对生长在3个不同海拔自然生境下微孔草(Microula sikkimensis)叶中的抗氧化系统进行了比较研究.结果表明,生长在高海拔的微孔草叶中抗氧化酶类SOD、POD和CAT活性比生长在低海拔的活性高,其中大通牛场的微孔草叶中3种酶活性最高;APX的活性随海拔的升高而升高,且低海拔地区西宁的APX活性极显著低于高海拔地区大通和海北站(P〈0.01);作为非酶抗氧化系统物质之一的抗坏血酸(ASA)含量随海拔的升高而降低.高海拔地区微孔草叶中可溶性糖含量极高(P〈0.01);可溶性蛋白含量随海拔升高呈V字形变化.光合色素Chl a、Chlb和Car的含量均随着海拔升高而增加,Chl a/b比值随海拔升高而降低.MDA的含量随海拔升高有增加的趋势,西宁和大通的相比较,MDA含量差异显著(P〈0.05),说明微孔草叶细胞膜脂过氧化程度随海拔升高加剧.生长在不同海拔高度的微孔草对不同海拔高度环境变化具有相应的生理适应性和抗氧化策略.

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研究了在野外自然条件下,长期增强UV-B辐射对高寒草甸3种典型植物矮嵩草(Kobresia humilis)、垂穗披碱草(Elymus nutans)和钉柱委陵菜(Potentilla saundersiana)光合放氧速率、光合色素和抗氧化系统的影响。结果表明:长期增强UV-B辐射对3种植物的净光合速率没有明显影响。增强UV-B辐射下,3种植物的叶绿素含量变化不同,Chla/b值,类胡萝卜素(Car)含量,Car/Chl值与对照相比都有升高,说明植物叶片的光合能力、吸收紫外线的能力增强以及忍受逆境能力均有增强,从而产生光保护,有利于光合作用正常进行。由于3种植物膜脂过氧化程度的不同及SOD活性的普遍抑制,植物经受了氧化胁迫。垂穗披碱草叶片GSH含量显著七升,矮嵩草的形态矮小及钉柱委陵菜GSH含量与POD活性显著上升,都能减轻它们所经受的氧化胁迫,使光合器官免受损伤。所以,这些保护性色素的积累和抗氧化系统内部的协同作用可能是高寒草甸植物光合作用正常进行的重要原因。

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Based on the study of fluvial sandstone reservoir in upper of Guantao group in Gudao and Gudong oilfields, this paper first introduces A.D.Miall's(1996a) architectural-element analysis method that was summarized from ground outcrop scale into the reservoir formation research of the study area, more subtly divides sedimentary microfacies and establishes sedimentary model of research area.on this base, this paper summarizes the laws of residual oil distribution of fluvial formation and the control effect of sedimentary microfacies to residual oil distribution, and reveals residual oil formation mechanism. These results have been applied to residual oil production, and the economic effect is good. This paper will be useful for residual oil research and production and enhancement of oil recovery in similar reservoir. The major conclusions of this paper are as follows. 1. Using the architectural-element analysis method to the core data, a interfacial division scheme of the first to the dixth scale is established for the studied fluvial formation. 2.Seven architectural-elements are divided in upper of Guantao group of study area. The sandstone group 5~1+2 of Neogene upper Gutao group belongs to high sinuous fine grain meandering river, and the sandstone group 6 is sandy braided river. 3. Inter layer, the residual oil saturation of "non-main layer" is higher than "main layer", but the residual recoverable reserve of former is larger. Therefore, "main layer" is the main body of residual oil distribution. The upper and middle part of inner layer has lower permeability and strong seeping resistance. Addition to gravity effect in process of driving, its driving efficiency is low; residual oil saturation is high. Because of controlling of inside non-permeable interlayer or sedimentary construction, the residual oil saturation of non-driving or lower driving efficiency position also is high. On plane, the position of high residual oil saturation mostly is at element LV, CS, CH (FF), FF etc, Which has lower porosity and permeability, as well as lens sand-body and sand-body edge that is not controlled by well-net, non-perfect area of injection and production, lower press difference resort area of inter-well diffiuent-line and shelter from fault, local high position of small structure. 4.Microscopic residual oil mainly includes the non-moved oil in the structure of fine pore network, oil in fine pore and path, oil segment in pore and path vertical to flow direction, oil spot or oil film in big pore, residual oil in non-connective pore. 5.The most essential and internal controlling factor of fluvial formation residual oil distribution is sedimentary microfacies. Status of injection and production is the exterior controlling factor of residual oil distribution. 6. The controlling effect of formation sedimentary microfacies to residual oil distribution indicates inter-layer vertical sedimentary facies change in scale of injection and production layer-series, planar sedimentary face change and inner-layer vertical sedimentary rhythm and interbed in single layer to residual oil distribution. 7. It is difficult to clear up the inter-layer difference in scale of injection and production layer-series. The using status of minor layer is not good and its residual oil saturation is high relatively. It is obvious that inter-layer vertical sedimentary facies changes control inter-layer residual oil distribution at the same or similar conditions of injection and production. For fluvial formation, this vertical sedimentary facies change mainly is positive gyration. Namely, from down to top, channel sediment (element CHL, LA) changes into over-bank sediment (element LV, CR, CS). 8. In water-injection developing process of transverse connecting fluvial sandstone oil formation, injection water always comes into channel nearby, and breaks through along channel and orientation of high pressure gradient, does not expand into side of channel until pressure gradient of channel orientation changes into low. It brings about that water-driving status of over-bank sedimentary element formation (LV, CR, CS) is not good, residual oil saturation is high. In non-connective abandoned channel element (CH) formation with channel, because this reverse is difficult to control by injection and production well-series, its using status is not good, even terribly not good, residual oil is enrichment. 9. The rhythm and sedimentary structure, sedimentary facies change in single sand body brings about vertical changes of formation character, growth character of inner layer interbed. These are important factor of controlling and affecting vertical water spread volume and inner layer residual oil forming and distribution in single sand body. Positive rhythm, is the principal part of fluvial sandstone inner layer sedimentary rhythm. Namely, from down to upside, rock grain granularity changes from coarse to fine, seeping ability changes from strong to feebleness. It brings about that water-driving status of inner layer upside is not good, residual oil saturation is high. Inner layer interbed has different degree affecting and controlling effect to seeping of oil and water. Its affecting degree lies on interbed thickness, extending scale, position, and jeted segment of production or injection well. The effect of interbed at upside of oil formation to oil and water seeping is less; the effect of interbed at middle of oil formation to oil and water seeping is more. 10. Indoor experiment and research indicate that wettability, permeability step, vertical permeability, position of Kmax and ratio of oil viscousity and water viscousity all have great effect on the water-driving recovery ratio. 11. Microscopic residual oil distribution is affected and controlled by formation pore network structure, pressure field distribution, and oil characteristic. 12.The residual oil forming mechanism: the over-bank sedimentary element and upper part of a positive rhythm sandstone have fine pore and throat network, permeability is low, displacement pressure of pore and throat is high. The water-driving power usually falls short of displacement pressure that brings about injection water does not spread into these pore and throat network, thereby immovable oil area, namely residual oil, is formed. At underside of channel sedimentary element and positive rhythm sandstone, porosity and permeability is relatively high, connecting degree of pore and throat is high, displacement pressure of pore and throat is low. Thereby injection water is easy to enter into pore and throat, driving oil in them. Because the pore space is irregular, the surface of pore wall is coarse and non-flat. That the oil locate on concave hole of pore wall and the dead angle of pore, and the oil attaches on surface of pore wall by surface tension, are difficult to be peeled off, becoming water-driving residual oil (remaining oil). On the other hand, Because flowing section lessens, flowing resistance increase, action of capillary fore, or seeping speed decreases at process of transfer at pass narrow throat path in the course carried by driving water. The "oil drop", "oil bead", or "oil segment" peeled off by driving water is difficult to carry and to drive out by water at less pressure difference. Thereby they are enclosed in pore to form discontinuous residual oil. 13.This results described above have been applied in nine develop blocks of Gudao and Gudong oilfield. Its applying effect is marked through local injection production adjustment, deploying replacement well, repair hole, replacement envelop, block off water and profile control etc. Relative method and technology can be applied to other oil production area of Shengli oilfield, and obtain better economic and societal effect.

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实验研究了菲在土壤/沉积物上的吸附一解吸过程。CHL土壤和HFH沉积物中有机质的固相^13C CP MAS NMR谱图很相似,表明样品中有机质的组成差异不大;菲在土壤/沉积物上的吸附过程表现出明显的非线性;线性模型不适合拟合菲的吸附等温线,Freundlich模型和双区位反应模型(DRDM)较好地拟合了菲的吸附等温线,其中DRDM模型还清楚地反映菲在低浓度和高浓度下不同的吸附方式;另外,研究表明菲在土壤/沉积物上的解吸过程中存在明显的滞后现象,这可能和土壤/沉积物有机质的异质性和土壤胶团微小孔隙的存在有关。实验研究了菲在土壤/沉积物上的吸附一解吸过程。CHL土壤和HFH沉积物中有机质的固相^13C CP MAS NMR谱图很相似,表明样品中有机质的组成差异不大;菲在土壤/沉积物上的吸附过程表现出明显的非线性;线性模型不适合拟合菲的吸附等温线,Freundlich模型和双区位反应模型(DRDM)较好地拟合了菲的吸附等温线,其中DRDM模型还清楚地反映菲在低浓度和高浓度下不同的吸附方式;另外,研究表明菲在土壤/沉积物上的解吸过程中存在明显的滞后现象,这可能和土壤/沉积物有机质的异质性和土壤胶团微小孔隙的存在有关。