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1.
合成了 1 5种 N-烷基 - O- (或 S) -烷基 - N′-取代 - N′-取代苯磺酰基磷酰二胺酯 ,并且通过质谱分析确定了其分子结构 ,其中 ( )和 ( )经文献检索均为新化合物。对部分化合物做了生物活性实验 ,发现化合物 ( )具有对小麦锈病和鲍鱼弧菌引起的菌病具有较好的抑制作用 ;化合物 ( )可有效阻断生物代谢中谷氨酸受体通道的传导 ,起到杀虫效果  相似文献   

2.
为深入解析水面浮油膜光谱特征,采用水面以上光谱测量方法,去除太阳直射和天空光两部分反射的影响,获取了珠江口水域不同厚度水面柴油膜光谱信息,对其光谱响应特征和机理进行了分析。结果表明:水面柴油膜光谱对背景水体光谱具有依赖性,但水面柴油膜光谱在可见光波段高于背景水体,且随着油膜厚度增加呈现不断增加的趋势;油膜反射光谱在蓝、紫光区域出现明显反射峰;360~500 nm区域油膜反射率与厚度相关系数大于0.8,有利于油膜厚度的遥感估算。最后指出,水面浮油膜类似于光学薄膜的单层增反膜,导致光谱反射率的增加,在360~420 nm区域的反射峰和石油类物质的荧光性有关。研究结果可为水域溢油污染遥感监测研究提供理论依据。  相似文献   

3.
研究了在高压汞灯照射下N,N′-二正辛基-3,3′-二硫代二丙酰胺的光降解过程,经由高效液相色谱法测定其残留含量。通过对比实验研究了不同初始浓度和光照强度对N,N′-二正辛基-3,3′-二硫代二丙酰胺光降解的影响。结果表明N,N′-二正辛基-3,3′-二硫代二丙酰胺在低浓度和高光强度时光降解速率更大,其降解过程符合动力学一级反应规律。  相似文献   

4.
采用油粒子模式,以原油为溢油油种,在模拟潮流的基础上分别预测了董家口30万t码头航道溢油油膜在静风、西北风和不利风向3种情况下的油膜动态漂移过程。对溢油油膜漂移路径及扫海范围的模拟,可为码头溢油应急计划的制定提供一定的导向作用。  相似文献   

5.
开发绿色环保防污剂是海洋船舶防污涂料研究的重要方向,查明防污活性化合物分子结构中的防污活性基团,是设计开发新型防污剂的关键。本文合成了三种结构相似的苯酰胺类化合物HNOB、DOLPA和DHNOB,通过FTIR,1H NMR,13C NMR测试表征三种化合物的分子结构,利用典型污损生物硅藻和贻贝作为目标生物,测试其对硅藻和贻贝附着的影响,并将分子结构与防污活性进行对比,初步探讨影响防污性能的活性基团。硅藻和贻贝附着实验均表明,HNOB的防污性能较好,半数抑制浓度远低于DOLPA和DHNOB。通过结构对比分析发现,极性和非极性结构的协同作用比单一的极性基团或非极性长碳链基团能更好地赋予苯酰胺类物质良好的防污性能。该研究初步探讨了苯酰胺类化合物的构效关系,有助于新型防污活性化合物的设计开发和结构优化,并对探究该类化合物防除污损生物附着的机理和快速筛选有潜力的防污化合物具有重要意义。  相似文献   

6.
渤海溢油三维漂移数值模拟研究   总被引:2,自引:0,他引:2  
黄娟  曹丛华  赵鹏  高松 《海洋科学》2015,39(2):110-117
国家海洋局北海预报中心于2011年开发了渤海三维溢油模型,该模型在分析国内外溢油模型现状的基础上,借鉴当今流行的数值模拟方法,使用油粒子模型与油膜扩展模型相结合的方式,用拉格朗日方法追踪每个带有一定油量的油粒子的轨迹,针对每一个油粒子则使用油膜扩展理论计算其油膜扩展过程。该模型可实现对溢油油污上升及水平输运过程、海表面油污浓度的预报,通过三组理想试验和2012年的海上溢油实验数据,对模型的各项功能、稳定性及模型精度进行了对比验证,结果较好,模型可实现对渤海海域海底或水下发生溢油的数值模拟。该模型解决了以往二维溢油模型在模拟钻井平台及海底输油管道泄漏等溢油事故方面的不足,可更好地为溢油灾害对海洋环境影响的估计提供有效参考信息。  相似文献   

7.
研究舟山海域溢油污染的问题,选用"油粒子"追踪模式,在潮流计算的基础上模拟了海上溢油动态.将海上溢油油膜离散为大量油粒子,每个油粒子代表一定油量,在表层海流和风的作用下漂移,而油膜的扩展则通过油粒子的随机走动来实现.本文以柴油为溢油油种,选择静风高潮时、低潮时和不利风向情况下的低潮时作为溢油初始时间,对溢油漂移路径及扫海范围进行了预测.  相似文献   

8.
激光诱导荧光(LIF)是一种主动光学探测技术,该技术已在海面未乳化溢油油种鉴别及油膜厚度评估方面取得了一定的研究成果,但乳化溢油的监测理论基础和探测方法尚未成熟。溢油乳化物的量化会直接影响溢油污染的应急处理和灾害评估,但目前对溢油乳化液溢油量的计算尚未有研究报道。本文以水包油乳化液为研究对象,基于等效思想,根据油量相等建立了水包油乳化液与油膜的荧光检测等效模型,并依据光的辐射传输机理推导出等效油膜厚度的估算公式,最后采用仿真实例对估算方法的适用性和有效性进行了验证。实验结果表明,当水包油乳化液含油率小于12×10-6,厚度小于5.98 cm时,利用所提出的等效方法能有效计算出水包油实际溢油厚度。该方法可为海面乳化溢油量的估算提供一种创新性的方法,具有良好的借鉴意义和实际应用价值。  相似文献   

9.
基于MIKE21水动力模型对围头湾海域进行潮流数值模拟,对比实测数据来验证模型模拟的潮位、流速及流向的可靠性。基于拉格朗日“油粒子”理论考虑油膜运动过程风化行为,建立了围头湾海域二维溢油扩散模型,模拟预测4个不同条件下油膜扫海面积及油膜对环境敏感区的污染情况。结果表明:溢油事故会对围头湾内环境敏感区均造成严重污染。夏季常风向(最不利风向)条件下油膜抵岸污染严重,72 h残油量高达46.7%,油膜漂移距离短,扫海面积小于60 km2;冬季常风向条件下油膜漂移距离远,扫海面积大于228 km2,但72 h残油量较低,为37.1%。  相似文献   

10.
海洋溢油油膜厚度影响因素理论模型的构建   总被引:4,自引:0,他引:4  
溢油扩展过程中油膜厚度的准确获得是进行溢油量估算和损失评估中需要解决的关键科学问题,通过揭示溢油扩展中油膜厚度的理论变化特征来获得油膜厚度随溢油性质和海洋环境条件变化的定量关系,构建海洋溢油油膜厚度影响因素理论模型,对溢油量估算至关重要。依据Lehr提出的油膜椭圆扩展模型构建了油膜厚度随溢油性质和海洋环境条件变化的定量关系,剖析了溢油扩展过程中油膜厚度的变化特征。油膜厚度在溢油发生后最初2小时内会迅速减小,此后衰减速度逐渐减小直至趋于稳定。对于原油来说,通常在6~7h内会达到最小油膜厚度,扩展终止。溢油密度对油膜厚度的影响表现为密度大的溢油初始厚度大,达到平衡的时间也较长;风速对于油膜扩展的影响巨大,风速越大越有利于油膜的扩展,油膜厚度越小;温度也通过影响溢油油膜密度来影响油膜厚度的变化,一定范围内,高温促进油膜的扩展,加快油膜厚度的变化速度。除溢油密度、风速和温度外,溢油方式、海流、潮汐和溢油时间等因素也会影响油膜厚度的变化。  相似文献   

11.
用长效肥料提高微生物分解海面油膜试验   总被引:1,自引:0,他引:1  
氮和磷是限制海洋油污生物降解的重要因素,采用可被微生物分解的两种蜡的混合物,把含有10:1的氮和磷的无机盐粉末包埋起来,制成亲油性且能与油膜漂浮在一起的长效肥料。在室内进行促进海水表面柴油油膜的生物氧化实验,结果表明:制备的长效肥料有促进油膜中烃类氧化微生物的生长和柴油的生物降解作用,实验9天除油率达到57 4%,对照实验仅24.5%。  相似文献   

12.
过杰  孟俊敏  何宜军 《海洋科学》2016,40(2):159-164
合成孔径雷达(SAR)以其高分辨率、能不受雨云影响实施全天时全天候全方位监测,在海面溢油灾害应急监测过程中发挥着越来越重要的作用。溢油是因为海面油膜抑制了毛细波和重力波,在SAR图像上呈暗斑而被识别。然而,海面溢油的乳化过程直接影响SAR对海面溢油后向散射截面的观测精度。本研究以物理海洋学和激光原理以及海面电磁散射理论为基础,通过实验利用激光扫描仪观测海面溢油粗糙度,分别与溢油特征参数、后向散射系数建立对应关系;耦合海面溢油参数与后向散射截面的关系,利用电磁散射数值建模方法,建立海面溢油散射模型,研究海面溢油乳化过程对微波后向散射截面的影响。本项目的研究将为SAR监测海面溢油量、溢油厚度及油品分布格局提供了可能;将进一步揭示海面溢油的散射机制,提高SAR海面监测溢油的精度和能力。  相似文献   

13.
事故性溢油对湄洲湾环境影响的预测   总被引:2,自引:0,他引:2  
汤军健  温生辉  陈彬 《台湾海峡》2002,21(3):332-339
本文采用已建立的湄洲湾潮流场和水质点拉格朗日运动模型,利用概率预测模式,描述一旦发生事故性溢油,海上表面油膜的漂移和扩展过程,预测最大可能的污染海域范围;并建立海上溢油动力模式,探讨连续排放溢油的漂移和扩展过程,通过Mackay公式算出在油膜覆盖下水体的油含量。  相似文献   

14.
海洋附着细菌对冠瘤海鞘幼体附着和变态的影响   总被引:7,自引:0,他引:7  
从冠瘤海鞘、皱瘤海鞘及乳突皮海鞘的被囊表面及其附着基和附近的海水中分离到290株细菌,根据其形态和生理生化特征,将其鉴定至弧菌属、肠杆菌属和无色杆菌属等10个属.分析海鞘被囊表面及其附着基和海水中的细菌组成,并从各属中挑出的29株细菌中分离筛选出附着能力较强的9株.将这9株细菌分别制成不同的单种细菌黏膜及9种细菌混合黏膜,检测细菌黏膜对冠瘤海鞘幼体附着和变态的影响.结果表明不同细菌黏膜对冠瘤海鞘幼体的附着和变态起不同的作用.无色杆菌属H-13显著地促进海鞘的附着和变态;弧菌属的H-4对海鞘的附着和变态均起抑制作用;弧菌属H-9明显地促进附着却强烈抑制海鞘幼体变态;其余细菌仅仅对海鞘幼体附着或变态的一个过程起作用或是对两者都没有明显效果.  相似文献   

15.
Microlayer samples from a coastal marine area near Marseilles (France) collected in 1979 and 1980 have been analysed for POC, PON, chlorophyll a, ATP, cell counts, carbon fixation and in some cases for heterotrophic activity. Comparison of microlayer data with those of underlying water showed in most cases enrichment of organic matter and microorganisms in the surface microlayer. Carbon fixation values were comparable to those observed at 0·50 m except in the slicks, where phytoneustonic activity was higher than that of the underlying phytoplankton. Though total heterotrophic activity was higher in the surface film, the turnover time was not significantly different in both microlayer and underlying water. Our data show that enrichment is highly dependent on sea conditions; whenever slicks are present, the surface film seems to function like an eutrophic system, including active living material, although detritus is regularly present in large amounts.  相似文献   

16.
Accurate detection of an oil spill is of great significance for rapid response to oil spill accidents. Multispectral images have the advantages of high spatial resolution, short revisit period, and wide imaging width, which is suitable for large-scale oil spill monitoring. However, in wide remote sensing images, the number of oil spill samples is generally far less than that of seawater samples. Moreover, the sea surface state tends to be heterogeneous over a large area, which makes the identification of oil spills more difficult because of various sea conditions and sunglint. To address this problem, we used the F-Score as a measure of the distance between forecast value and true value, proposed the Class-Balanced F loss function (CBF loss function) that comprehensively considers the precision and recall, and rebalances the loss according to the actual sample numbers of various classes. Using the CBF loss function, we constructed convolution neural networks (CBF-CNN) for oil spill detection. Based on the image acquired by the Coastal Zone Imager (CZI) of the Haiyang-1C (HY-1C) satellite in the Andaman Sea (study area 1), we carried out parameter adjustment experiments. In contrast to experiments of different loss functions, the F1-Score of the detection result of oil emulsions is 0.87, which is 0.03–0.07 higher than cross-entropy, hinge, and focal loss functions, and the F1-Score of the detection result of oil slicks is 0.94, which is 0.01–0.09 higher than those three loss functions. In comparison with the experiment of different methods, the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.05–0.12 higher than that of the deep neural networks, supports vector machine and random forests models, and the F1-Score of the detection result of oil slicks is 0.15–0.22 higher than that of the three methods. To verify the applicability of the CBF-CNN model in different observation scenes, we used the image obtained by HY-1C CZI in the Karimata Strait to carry out experiments, which include two studies areas (study area 2 and study area 3). The experimental results show that the F1-Score of CBF-CNN for the detection result of oil emulsions is 0.88, which is 0.16–0.24 higher than that of other methods, and the F1-Score of the detection result of oil slicks is 0.96–0.97, which is 0.06–0.23 higher than that of other methods. Based on all the above experiments, we come to the conclusions that the CBF loss function can restrain the influence of oil spill and seawater sample imbalance on oil spill detection of CNN model thus improving the detection accuracy of oil spills, and our CBF-CNN model is suitable for the detection of oil spills in an area with weak sunglint and can be applied to different scenarios of CZI images.  相似文献   

17.
星载SAR监测海洋溢油污染的初步研究   总被引:1,自引:0,他引:1  
对星载SAR监测海洋溢油的基本原理进行总结并分析了影响溢油监测的SAR参数及干扰SAR海洋溢油监测的各种因素;对搜集到的星载SAR数据进行处理,并给出中国黄海海域的海上溢油分布的初步统计分析,结果表明该海区的溢油主要分布在海上主要航线附近。  相似文献   

18.
Abstract

Two groups of oil slicks have been repeatedly detected in the Southern Caspian Sea, off Cape Sefidrud and close to the Iranian coast of the sea on the synthetic aperture radar (SAR) images acquired by the Sentinel-1A and Sentinel-1B satellites in April–June 2018. Analysis of the SAR images together with bathymetry, geological and geophysical data in geographic information system showed that these manifestations (oil slicks) visible on the sea surface have natural origin, related to the bottom seepage phenomenon and are associated with existing hydrocarbon system. Oil slicks are concentrated over the continental slope and related to local geological formations of the sedimentary cover having oil deposits related to paleo-delta of Sefidrud River. Our evidence shows that two seeps in this area are active and repeating. It is concluded that the SAR is an excellent tool for monitoring of seepage phenomenon. Moreover, results indicate that the use of remote methods to identify offshore natural oil seeps related to existing active petroleum system can be considered as a well-accepted approach to support oil and gas exploration in frontier areas such as the South Caspian Basin.  相似文献   

19.
A continuation of the work dedicated to the study of slicks and film formations on the sea surface is presented. A vector model for the calculation of reflected radiation by the wavy sea surface with respect to the contribution of upwelling radiation from under the sea surface (the second type of waters) is described briefly in [5]. This work contains an analysis of numerical calculations according to the developed procedure and the search for optimal conditions of slick detection. The best conditions for detecting slicks on the sea surface are reached when a P-polarization component of reflected radiation is recorded. In this case, the value of contrast between a slick and a clean surface is 30% higher on average than in recording a contrast without using a polarization filter and is 50% higher than in the case of recording a contrast with a filter oriented to the maximum transmission of S polarization component of reflected radiation. It is shown that, under clear sky conditions, the optimal condition for recording slicks on a sea surface is videotaping in the plane of solar vertical at viewing angles sliding towards the sea surface and when a polarization filter that identifies the Р polarization component of sea radiation is used. In contrast, under overcast sky conditions, it is best to perform observations in the plane that has a wind velocity vector.  相似文献   

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