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1.
文章于2018年1月(冬季)、4月(春季)、7月(夏季)、10月(秋季)对我国考洲洋海域海水中的溶解氧(DO)、化学需氧量(COD)、无机氮(DIN)、活性磷酸盐(DIP)4个主要海水水质因子进行了综合调查。结果表明,4个水质因子DIP、DIN、COD、DO的平均浓度由高到低的季节变化分别为:冬季(0.058 mg/L)、春季(0.046 mg/L)、夏季(0.009 mg/L)、秋季(0.006 mg/L);冬季(0.465 mg/L)、春季(0.171 mg/L)、夏季(0.064 mg/L)、秋季(0.040 mg/L);夏季(1.57 mg/L)、冬季(1.26 mg/L)、秋季(1.22 mg/L)、春季(0.89 mg/L);冬季(11.70 mg/L)、夏季(7.41 mg/L)、秋季(7.36 mg/L)、春季(7.18 mg/L)。评价结果显示,春季和冬季主要超标因子为DIP和DIN,夏季超标因子为DIP,秋季水质因子均满足要求。同时,本研究利用单因子标准指数法、富营养化指数法和有机污染评价指数法对考洲洋地区水质状况进行评价并对其进行初步比较和分析,结果表明,3种方法在季节性变化上的评价结果基本一致(由高到低均为:冬季、春季、夏季、秋季),然而,同一季节不同评价方法的超标站位比例不同(单因子指数法:冬季占100%,春季占80%,夏季占10%,秋季则无;富营养化指数法:冬季占90%,春季占70%,夏季和秋季均为无;有机污染指数评价法:冬季和春季均占80%,夏季和秋季均为无),比较分析表明,3种评价方法具有不同的评价作用和适用性。  相似文献   

2.
目的:观察委中穴不同针刺手法治疗血瘀型腰椎间盘突出症(LDH)急性发作的临床疗效。方法:将80 例LDH患者随机分为治疗组和对照组,每组各40 例。治疗组采用石氏针刺法治疗,对照组采用常规针刺法治疗,2组主穴取委中、肾俞、大肠俞、阿是穴,配穴取膈俞。2组疗程均为2周,治疗结束1周后复诊。比较2组治疗前、治疗后、复诊时腰椎功能评分量表(JOA)评分、0swestry功能障碍指数、疼痛视觉模拟评分法(VAS )评分,评价安全性和综合疗效。结果:总有效率治疗组为92.5%(37/40),对照组为77.5%(31/40),2组比较,差异有统计学意义(P<0.05);2组JOA评分、0swestry功能障碍指数、VAS评分治疗后、复诊时与本组治疗前比较,差异均有统计学意义(P<0.05),且治疗组与对照组同时间节点比较,差异均有统计学意义(P<0.05)。结论:石氏针刺法针刺委中穴治疗血瘀型LDH急性发作,相对于常规针刺法,在提高腰椎功能、缓解疼痛方面具有明显的优势,值得临床推广应用。  相似文献   

3.
在频域中分别使用Rankine面元法和去奇点Rankine面元法(desingularized-Rankine panel method,简称DRPM)快速求解有航速船舶耐波性问题。使用两种不同的线性化方式:叠模流线性化法(double-body flow,简称DB)和均匀流线性化方法(Neumann-Kelvin,简称NK)计算了Wigley I、Wigley III和S175在有航速时船舶的水动力系数、波浪激励力和运动响应。两种线性化方法的计算结果与试验结果进行了比较,研究表明:使用Rankine面元法和去奇点Rankine面元法计算的结果相差不大,且与NK法相比使用DB法计算的结果和试验值更吻合,尤其是非对角线上交叉耦合水动力系数A35,B35,A53,B53的计算结果。运动响应对于边界条件线性化方式比较敏感,尤其是垂荡运动,在船共振频率附近,运动受到的影响最明显。  相似文献   

4.
本文从界面热力学理论方面证明了海上溢油分散剂主要是通过降低溢油与海水之间的界面张力(IFT),减少分散过程所需要的自由能以使溢油的分散易于实现。实验中测定了含有不同种类溢油分散剂的原油与模拟海水之间的界面张力(旋转滴法)、界面粘度(IFV,深槽法)及分散效果(回旋振荡法),表明对于本研究工作中使用的体系,较好的分散效果必须使IFT降低到10~(-1)mN·m~(-1)以下,而界面粘度对分散效果的影响不甚显著。  相似文献   

5.
大西洋金枪鱼渔业现状分析   总被引:4,自引:0,他引:4  
本文采用大西洋国际金抢鱼保护委员会ICCAT的报告和统计常设委员会(SCRS)数据库,统计分析了1978-2002年大西洋金抢鱼的渔获种类及渔具渔法。结果表明:按种类分黄鳍金枪鱼(占28%)、鲣鱼(22%)、长鳍金枪鱼(15%)、大眼金枪鱼(11%)、其他种类(8%);按渔具分围网(42%)、延绳钓(29%)、饵钓(22%)、其它渔具(7%)。同时分析了不同海域的渔获种类、渔获量波动情况和原因。  相似文献   

6.
对我国油气资源评价工作中常用的基本概念与评价方法进行了详细阐述,其中包括美国石油工程师协会(SPE)、俄罗斯和我国新实行的油气资源分类标准和基本概念;将油气资源评价方法分为:成因法、类比法、统计法、德尔菲(Delphi)法4大类;较详细的介绍了盆地模拟法、氯仿沥青“A”法、有机碳法、面积丰度法、体积丰度法、统计趋势预测法、油气田(藏)规模概率分布法、地质因素分析法、圈闭法等具体评价方法,并简要分析了它们的适用范围和特征。  相似文献   

7.
鳗鲡气单胞菌引起的烂尾病病原菌抑菌药物的研究   总被引:5,自引:0,他引:5  
应用药敏纸片法研究了三株烂尾病病原菌(气单胞菌)对31种药物及不同配合药物的敏感性,测定了4种药物及配合药物HP对三株菌的最低抑菌浓度(MIC)及最低杀菌浓度(MBC)。结果表明,配合药物HP具较强的抑菌能力。  相似文献   

8.
生物样品中重金属含量的分析测试法比较研究   总被引:3,自引:0,他引:3  
孙平跃  王斌 《黄渤海海洋》2002,20(2):99-104
用电感耦合等离子体原子发射光谱仪(ICP-AES)和石墨炉原子吸收光谱仪(GAAS)分别测定河蚬样品中镉和铬的含量,以比较不同测试方法对这两种重金属测定的影响,结果表明:2种测试法对生物样品中镉和铬含量的测定结果都有显著的影响,同一样品中镉和铬含量的ICP-AES测定值均显著高于其相应的GAAS测定值,相比ICP-AES法,GAAS法对河蚬样品中镉和铬含量的测定更为准确,不同方法测定的镉和铬含量的差异程度分别为18.8%和136.4%,本研究显示,不同测试法对铬含量测定结果的影响比对镉含量测定结果的影响更大。  相似文献   

9.
2.4拟庸蝶食性的对应分析2.4.1观察量和变量的分组观察量(捕食鱼类)依不同季节(冬、夏季)、不同性别(雌雄性)和不同性成熟状态(幼鱼和成鱼)来分组,因此得到8(23)个观察量。对应分析的变量(饵料)首先根据个体生态的不同分为6个类型:游走多毛类,隐居多毛类,双壳类,不大游动的甲壳类(端足目和等足目),爬行甲壳类(十足国短尾部)和棘皮动物。其他6个类型的饵料生物(类、纽虫类、小型游泳甲壳类、腔肠动物、鱼类及苔藓虫类顺在分组时剔除,其原因为它们的出现可能少了些。考虑到捕食鱼类和饵料双壳类贝壳厚度…  相似文献   

10.
用96孔酶标板法测量单尾中国对虾血淋巴上清液抗菌(Uα)应力和过氧化酶活性。实验表明,该法具有以下优点:1)可测定大批单尾对虾血淋巴上清液的抗菌活力,酚氧化酶活性;2)所需对虾血淋巴上清液微量化;3)用酶标仪读取酶的活性,减少了不同试验者人为读数时的误差;4)重复性高。  相似文献   

11.
The provenance of detrital quartz is a useful predictor in frontier basin sandstone reservoirs of the availability of coarse-grained quartz grains of plutonic or high grade metamorphic origin. The standard approach is to use scanning electron microscope (SEM) panchromatic cathodoluminescence (CL) imagery and observations from an optical petrographic microscope. We describe a work flow, modified from previous literature proposals, to determine quartz provenance in detrital grains using optical petrographic microscopy and CL properties from both a hot-cathode cathodoluminescence microscope attachment (HCMA) and panchromatic SEM-CL. HCMA analysis permits better discrimination of different types of metamorphic quartz. This method is applied to a Middle Jurassic to Lower Cretaceous section in the Bandol-1 wildcat well, located in the Laurentian sub-basin south of Newfoundland. Two types of high-grade metamorphic quartz are distinguished, one with low luminescence as described in previous literature and one with medium blue CL colour and a moderate colour shift that is also known from granulite in the hinterland. Three phases of detrital supply are identified, suggesting progressive unroofing of higher grade metamorphic sources through the middle Jurassic and major input of plutonic quartz in the early Cretaceous.  相似文献   

12.
以成因矿物学的理论和方法,围绕太平洋三区四地海底热液硫化物和烟囱物中黄铁矿为主线的形态标型(扫描电镜)、矿物标型(粉晶X射线衍射法)及矿物组合,揭示了黄铁矿及伴生矿物在不同热液喷发类型中的标型特征,并由此反证了不同标型特征的热液矿物与热液喷发环境相互依存的紧密关系。  相似文献   

13.
The current methods used in world practice for the determination of the basic parameters of the vital functions of bacterioplankton (the number, biomass, and production) are discussed. While comparing the different methods and their modifications, the peculiarities of their application for particular natural or laboratory environments are emphasized. The specificity of applying different microbiological methods for field research is examined. When choosing the methodological base for describing the characteristics of a bacterial community, one should proceed from the specific problem facing the researcher. In the case of routine monitoring, the following techniques are convenient and widely used: direct counts of DAPI fluorochrome-stained bacteria using a fluorescence microscope; the calculation of the biomass of the microorganisms on the basis of the relationship between the cell’s mass and its size; the estimation of the bacteria production via labeled leucine incorporation.  相似文献   

14.
深水土工调查技术和分析方法新进展   总被引:1,自引:0,他引:1  
王淑云  鲁晓兵 《海洋工程》2007,25(2):126-130
简要介绍了近年来国外在深水土工调查技术和分析方法方面取得的新进展,包括:钻孔取样技术在钻入模式和取样器的多样化和有效组合,从而实现不同水深和不同土类条件下的高质量取样;带孔压测量的圆锥触探试验在测量方法、孔压测量单元设计、探头的小型化和多样化、数据的快速传输以及分析理论方面的进展;减少土样扰动,准确评估粘土不排水抗剪强度的“SHANSEP”室内试验方法及应用。  相似文献   

15.
This paper makes an assessment of the various method that may be used to analyse experiment data on the force experienced by a circular cylinder in waves and combined wave and current flows to estimate drag and inertia coefficients for use in Morison's equation. Most of the widely used techniques are considered together with a weighted least squares approach for time domain analysis. A set of data obtained from experiments on heavily roughened circular cylinders of diameters 0.513 and 0.216 m in the Delta wave flume at De Voorst in Holland in waves and simulated current has been analysed in turn by all these techniques. The experiment data was split into two halves. The first was used for the analyses and the second was used to assess the predictive accuracy of Morison's equation. Using the force coefficients obtained from the different analysis techniques corresponding predicted force time series were constructed using the particle kinematics measured in the second parts of the data sets. These predicted time series were then compared with the corresponding measured force time histories. The root mean square error and the bias in the estimation of maximum force in each wave cycle are used as measures of predictive accuracy and as a basis for comparing the efficiency of the different analysis techniques. It was found that the weighted least square method generally gave the best predictive accuracy, but only by a small margin.  相似文献   

16.
Marine risers are susceptible to sustained vortex-induced vibration (VIV) because of their slenderness and light damping. Commonly used tools for analyzing VIV and the associated fatigue damage are based on the finite element method and rely on simplifying assumptions on the riser's physical model, the flow conditions, and characteristics of the response. In order to assess the influence of VIV and to ensure the integrity of the riser, field monitoring campaigns are often undertaken wherein data loggers such as strain sensors and/or accelerometers are installed on such risers. Given the recorded riser's dynamic response, empirical techniques can be used in VIV-related fatigue estimation. These empirical techniques make direct use of the measurements and are intrinsically dependent on the actual current profiles. Damage estimation can be undertaken for the different current profiles encountered and can account explicitly even for complex riser response characteristics. With a significant amount of data, “short-term” fatigue damage probability distributions, conditional on current, can be established. If the relative frequency of different current types is known from a separate metocean study, the short-term fatigue damage distributions can be combined with the current distributions to yield an integrated “long-term” fatigue damage model, which then can be used to predict the long-term cumulative fatigue damage for the instrumented riser. Non-parametric statistical techniques (that do not assume a specific function for the underlying distribution as parametric techniques do) are employed to describe the short-term fatigue damage data. In this study, data from the Norwegian Deepwater Programme (NDP) model riser experiments are used to demonstrate the effectiveness of empirical procedures and non-parametric statistics applied to field measurements to predict long-term fatigue damage, life, and probability of fatigue failure.  相似文献   

17.
Sezen  Savas  Bal  Sakir 《中国海洋工程》2020,34(2):232-244
In this study, non-cavitating and cavitating flow around the benchmark DTMB 4119 model propeller are solved using both viscous and potential based solvers. Cavitating and non-cavitating propeller radiated noises are then predicted by using a hybrid method in which RANS(Reynolds-averaged Navier-Stokes) and FWH(Ffowcs Williams Hawkings) equations are solved together in open water conditions. Sheet cavitation on the propeller blades is modelled by using a VOF(Volume of Fiuld) method equipped with Schnerr-Sauer cavitation model.Nevertheless, tip vortex cavitation noise is estimated by using two different semi-empirical techniques, namely Tip Vortex Index(TVI, based on potential flow theory) and Tip Vortex Contribution(TVC). As the reference distance between noise source and receiver is not defined in open water case for TVI technique, one of the outputs of this study is to propose a reference distance for TVI technique by coupling two semi-empirical techniques and ITTC distance normalization. At the defined distance, the starting point of the tip vortex cavitation is determined for different advance ratios and cavitation numbers using potential flow solver. Also, it is examined that whether the hybrid method and potential flow solver give the same noise results at the inception point of tip vortex cavitation.Results show that TVI method based on potential flow theory is reliable and can practically be used to replace the hybrid method(RANS with FWH approach) when tip vortex cavitation starts.  相似文献   

18.
海洋涡旋作为一种快速连续变化的海洋现象,如何分析和挖掘其移动特征成为当前海洋涡旋定量研究的重点。本文引入空间数据挖掘的社区网络划分方法,将涡旋过程看作复杂的移动网络,对涡旋移动的聚集性特征进行探索和分析。首先,以网格为统计单元对1992-2011年近20年南海海洋涡旋移动数据进行组织,基于图论模型构建了涡旋瞬时移动(TP),涡旋移动起止点(OD),涡旋最小描述距离的特征点移动网(MDL)和涡旋过程移动再生数据(RSP)4种状态的海洋涡旋的移动网络图;其次,采用基于快速模块度优化的区域划分方法分别得到4种状态下涡旋移动的聚集性区域;最后,利用弦图对区域内和区域间涡旋移动规律进行了可视化分析,发现海洋涡旋的RSP数据能够弥补原始涡旋移动数据在区域划分方法中呈现的数量不足的问题,能够在足够数据量的情况下,有效地发现从起点到终点的主要移动通道和涡旋移动的聚集性区域,这些区域反映了南海涡旋从其产生、发展到结束整个演化过程的聚集性特征。  相似文献   

19.
China is arguably one of the countries where the most tunneling and underground projects are being performed. Recently in China, it has often been necessary to construct tunnels under many types of conditions and to develop new techniques. Currently, some advanced construction techniques cannot be appropriately applied to different types of underground conditions, and many traditional methods are still often used. However, because of the progress in tunnel boring machines (TBM), innovations are required for the construction method. This article introduces the current situation of TBM both in western countries and in China, and examines the future of TBM in China.  相似文献   

20.
China is arguably one of the countries where the most tunneling and underground projects are being performed. Recently in China, it has often been necessary to construct tunnels under many types of conditions and to develop new techniques. Currently, some advanced construction techniques cannot be appropriately applied to different types of underground conditions, and many traditional methods are still often used. However, because of the progress in tunnel boring machines (TBM), innovations are required for the construction method. This article introduces the current situation of TBM both in western countries and in China, and examines the future of TBM in China.  相似文献   

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