南极普里兹湾沉积物中的糖类分布及意义   总被引：1，自引：1，他引：0       下载免费PDF全文

于培松  扈传昱  朱小萤  潘建明  张海生 《海洋学报》2008,30(1):59-66

利用中国第18和21次南极考察获取的南极普里兹湾沉积物样品,分析了其中的有机碳和糖类物质的含量及组成,结果表明糖类和有机碳的分布受上层水体的初级生产、地形条件和水体垂直稳定度等多种因素的控制。表层沉积物中糖类物质的平均含量为3.03 mg/g,最高值为5.60mg/g,出现在湾内的毗邻陆架区。沉积物有机碳含量与表层海水叶绿素a具有良好的相关性,能够反映上层水体初级生产的变化。单糖组分的研究可以判定其生源母质,沉积物中有机质的来源主要是海洋上层生物。糖类是易被降解利用的有机质,通过糖类物质中六碳糖的比重及其垂直分布的变化可以判断出不同站位沉积速率的相对快慢。  相似文献   

Immunotoxicity Effect of Benzo[α]Pyrene on Scallop Chlamys f arreri     

ZHANG Lin  PAN Luqing  LIU Jing 《青岛海洋大学学报(英文版)》2009,(1):89-94

The toxic effects of benzo[α]pyrene （B[α]P） at different concentrations （0.1, 0.5, 1, 2.5 and 7.5 μgL^-1） on scallop （Chlamys farreri） immune system were studied. The results showed that B[α]P had significant toxic effects on the haemocyte counts, neutral red uptake, phagocytosis, bacteriolytic and antibacterial activity （P〈0.05）, while the seawater control and acetone control had no significant differences. The haemocyte counts, neutral red uptake, phagocytosis and bacteriolytic activity in all B[α]P treatment groups as well as antibacterial activity in groups of 0.5, 1, 2.5 and 7.5 μgL^-1·B[α]P decreased significantly （P〈0.05）. Some of these indices tended to be stable on the sixth day and others on the ninth day, and the indices showed clear time- and concentration-response to B[α]E Bactenolytic activity in 0.1 μgL^-1 B[α]P treatment group and antibacterial activity in 0.1 ggLl and 0.5 μgL^-1 B[α]P treatment groups increased at the beginning of exposure and reached their peaks on day 1 and day 6, respectively. Following that, both activities decreased gradually and became stable after day 9. When all the indices reached stability, they were significantly lower than those in control group （P〈0.05）, except for antibacterial activity in 0.1 μgLl B[α]P treatment group （P〉0.05）. Thus, B[α]P has evident toxic effects on scallop immune system, which supports the view that a relationship exists between pollution and lmmunomodulation in aquatic organisms.  相似文献   

Height prediction of water flowing fractured zones based on BP artificial neural network     

YANG Liu  WEN Xue-ru  WU Xiao-li  PEI Li-xin  YUE Chen  LIU Bing  GUO Si-jia 《地下水科学与工程》2014,7(4):354-359

Factures caused by deformation and destruction of bedrocks over coal seams can easily lead to water flooding (inrush) in mines, a threat to safety production. Fractures with high hydraulic conductivity are good watercourses as well as passages for inrush in mines and tunnels. An accurate height prediction of water flowing fractured zones is a key issue in today's mine water prevention and control. The theory of leveraging BP artificial neural network in height prediction of water flowing fractured zones is analysed and app-lied in Qianjiaying Mine as an example in this paper. Per the comparison with traditional calculation results, the BP artificial neural network better reflects the geological condi-tions of the research mine areas and produces more objective, accurate and reasonable results, which can be applied to predict the height of water flowing fractured zones.  相似文献   

中性氧化铝对原油链状烷烃和芳烃组分吸附行为     

陈祖林  彭相林  王细超  张敏 《地质科技情报》2010,29(2)

将吸附原油的中性氧化铝柱用正己烷、含5%二氯甲烷的正己烷逐步淋洗链状烷烃,用二氯甲烷与正己烷体积比为2∶1的试剂逐步淋洗芳烃,通过分析淋洗过程中所得到的各个产物的色谱检测结果来揭示原油中链状烷烃和芳烃在中性氧化铝层析柱上的解析过程,提出了中性氧化铝作为层析柱吸附剂的结构模型,探讨了原油中链状烷烃、芳烃在中性氧化铝层析柱上的吸附机理,为原油中链状烷烃、芳烃的快速、完全分离提供理论依据。  相似文献   

New Zealand's abandonment of the Carbon Neutral Public Service programme     

Jeff Birchall 《Climate Policy》2013,13(4):525-535

In 2009, New Zealand's new National-led government abandoned the Carbon Neutral Public Service (CNPS) programme, a Labour-led government initiative intended to help Government achieve carbon neutrality within its core agencies. This short analysis article provides an overview and brief assessment of the CNPS initiative by drawing on the relevant scholarly literature and public documents relating to New Zealand's climate change agenda. It is argued that although the CNPS programme faced a range of challenges it was successful in some respects. Although the Labour-led government was keen to act on climate change mitigation, New Zealand no longer intends to take a lead on carbon neutrality under the National-led government.  相似文献   

GPS中性大气折射延迟的研究   总被引：1，自引：0，他引：1  

张捍卫  铁琼仙  杨磊 《大地测量与地球动力学》2006,26(4):1-5

简述了GPS大气折射延迟研究的进展,针对GPS对中性大气折射延迟改正精度的要求,给出了研究天文大气折射和中性大气折射延迟的一个可能方法,即:基于映射函数形式的天文大气折射模型,利用不同方位的天文大气折射值的测定数据,求解映射函数中的参数,进而可建立随观测站和随方位而异的大气折射延迟改正模型。  相似文献   

米曲霉中性蛋白酶特性的研究     

杨世平  邱德全 《广东海洋大学学报》2006,26(4):22-25

研究了米曲霉中性蛋白酶的特性。结果表明,米曲霉中性蛋白酶的最佳提取方法为加入pH 7.2的缓冲液研匀,置恒温(30℃)培养箱中提取30 min,每10 min搅动1次,最后用4层纱布过滤。酶反应最适温度为55℃,最适pH值为7.2。NaCl和EDTA对其有一定的抑制作用。酶的热稳定性好,在45℃的温度下处理24 h后,酶活力仍有45.5%。米曲霉中性蛋白酶与培养物一起保存时,稳定性也较好,在4℃保存一个月后,酶活力几乎无变化。  相似文献   

Review of Global Ocean Intermediate Water Masses: 1.Part A,the Neutral Density Surface (the ''McDougall Surface'') as a Study Frame for Water-Mass Analysis     

Yuzhu You 《中国海洋大学学报(英文版)》2006,(3)

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The structure of Galactic gas at high latitudes: The southern polar cap     

I. V. Gosachinskii  G. N. Il'in  V. A. Prozorov 《Astronomy Letters》2004,30(4):232-239

We analyze the angular structure of the 21-cm interstellar neutral hydrogen emission at six and seven declinations in the northern (published previously) and southern polar caps of the Galaxy (Galactic latitudes from ?40° to ?90°), respectively, with an extent of 90° in right ascension. The RATAN-600 radio telescope has a beam width averaged over these regions of 2.′0×30′. One-dimensional power spectra for the angular distribution of interstellar neutral hydrogen emission were computed in each 6.3-km s^?1-wide spectral channel by using the standard Fast Fourier Transform (FFT) code and were smoothed over 1^h in right ascension. The Galactic latitude dependence of the mean parameters for the sky distribution of H I line emission at high latitudes was found to correspond to the distribution of gas in the form of a flat layer only in the northern region, while in the southern cap, the gas distribution is much less regular. In addition, the mean H I radial velocities are negative everywhere (?3.7±3.0 km s^?1 in the north and ?6.0±2.4 km s^?1 in the south). The power spectra of the angular fluctuations in the range of angular periods from 10′ to 6° appear as power laws. However, the spectral indices change greatly over the sky: from ?3 to ?1.2; on average, as the Galactic latitude increases and the H I column density decreases, the fluctuation spectrum of the interstellar gas emission becomes flatter. In the northern polar region, this behavior is much more pronounced, which probably stems from the fact that the gas column density in the south is generally a factor of 2 or 3 higher than that in the north. Therefore, the spectra are, on average, also steeper in the south, but the dependence on Galactic latitude is weaker. Using simulations, we show that the observed power-law spectrum of the H I emission distribution can be obtained in terms of not only a turbulent, but also a cloud model of interstellar gas if we use our previous spectra of the diameters and masses of H I clouds.  相似文献   

偏振遥感的中性点大气纠正方法研究   总被引：4，自引：3，他引：1  

吴太夏  张立福  岑奕  黄长平  赵恒谦  孙雪剑 《遥感学报》2013,17(2):235-247

地表物体具有较强的偏振特性, 因此可以作为偏振遥感的信息源。但是, 大气的偏振效应强于地表的偏振效应, 导致星载遥感器无法有效接收地表目标的偏振信息, 大气的起振与退偏效应成为偏振遥感对地表目标进行观测和应用的一个瓶颈问题。本文提出一种利用大气中性点对偏振遥感中地表偏振效应与大气偏振效应进行分离的方法, 通过天空中大气线偏振度为零的中性点区域进行对地观测, 目的是去除大气偏振作用, 进而最大限度地获取地表目标偏振信息。地面实验的结果验证了利用大气中性点进行大气纠正具有理论上的可行性。  相似文献