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1.
以合浦珠母贝Pinctadamartensii(Dunker)作为珠母贝进行插核育珠试验,分别以其左、右边外套膜作为小片,并用珍珠生长激素浸泡小片。两个试验组用珍珠生长激素浸泡的小片各插核育珠贝200个,空白对照组用海水浸泡小片括核育珠贝207个,育珠时间为6个多月。试验结束时,实验组珍珠的正圆珠率、白色珍珠比例以及珠层厚度比空白对照组分别提高了9.28%,22.57%和52μm。  相似文献   

2.
术前处理和室内水池休养对提高珍珠产量和质量的影响   总被引:8,自引:0,他引:8  
作者在近几年的珍珠生产中发现,育珠贝成活率很低,从母贝植核到收珠,育珠贝成活率不到50%,有的仅在休养期就死亡50%~60%;其次,育珠贝的留核率,平均只有25%~35%,而所产珍珠颗粒小、珠层薄、形状差、销路不畅,造成珍珠养殖场生产效益差,在国际市场上缺乏竞争力。为此,1995年4月1日~10月31日,作者在湛江水产学院珍珠试验场进行了一系列提高珍珠产量和质量的试验工作。其中以术前处理和室内地休养效果最显著。1材料和方法1.1试验材料1.1.1试验用贝选自湛江市硇洲岛、徐闻县和安镇以及雷州市覃…  相似文献   

3.
珍珠生长激素在合浦珠母贝育珠中的作用   总被引:5,自引:0,他引:5  
金启增  黎辉 《热带海洋》1998,17(4):44-50
以合浦珠母贝Pinctada martensii (Dunker)作为珠母贝进行插核育试验,分别以其左、右边外套膜作为小片,并用珍珠生长激素浸泡小片,两个试验用珍珠生长激素浸光怕小片各插核育珠贝200个,空白对组用海水浸泡小片插核育珠贝207个,育珠时间为6个多月。试验结束时,实验组珍珠的正圆珠率,白色珍珠比例以及珠层厚度在比空白对照组分别提高了9.28%,22.57%和52μm。  相似文献   

4.
近年来,极谱分析特别是催化极谱和阳极溶出伏安法,由于其灵敏度高.设备简单,在微量和超微量分析中得到普遍重视,并广泛用于各种实际工作.利用极谱方法研究水溶液体系中元素的存在形态和动力学过程的工作,亦已逐渐开展。但是,当溶液中电解质含量过低,例如在有机溶液、  相似文献   

5.
通过红外光谱、扫描电镜、能谱等方法探讨了合浦珠母贝贝壳珍珠层EDTA可溶性基质蛋白(ESM)对无定形碳酸钙(ACC)晶型转化的影响。试验结果显示,合浦珠母贝贝壳珍珠层ESM在镁离子存在的条件下能够显著抑制ACC的转化,并减少最终诱导形成的方解石中的镁离子含量。同时,珍珠层ESM具有调节方解石晶体晶貌的作用。  相似文献   

6.
使用正电子湮没谱学方法,在不同气氛下对电化学腐蚀法制备的多孔硅中电子偶素的湮没行为进行了系统的研究.正电子湮没寿命谱测试结果表明,样品中存在长达40 ns的电子偶素湮没成分,并且进入多孔硅膜层的正电子约有80%形成电子偶素,具有非常高的电子偶素产额;在氧气气氛下,由于气体导致o-Ps发生自旋转化猝灭是使多孔硅样品中电子偶素寿命缩短的主要原因.结合正电子寿命-动量关联谱测量结果,分析了不同气氛下多孔硅样品中电子偶素湮没寿命及动量变化关系,讨论了多孔硅中电子偶素的湮没机理以及气氛对孔径计算理论模型的影响.  相似文献   

7.
基于南海深水区波浪实测资料,对双峰型海浪谱的演化过程进行了分析,并对双峰型海浪的波高、波向、谱峰周期、出现时间和常用双峰谱模型的适用性等方面进行了研究。结果表明,双峰型海浪出现时波高普遍小于2m,其涌浪部分谱峰周期约11.37s;Ochi-Hubble谱在南海的适用性较好。研究成果可为南海深水区油气资源的开发、设计提供参考。  相似文献   

8.
从市场角度探讨养殖有核珍珠的质量   总被引:1,自引:0,他引:1  
养殖有核珍珠是指珍珠贝在人工养殖(含插核)下形成的珍珠。这类珍珠 ,大多数用于装饰品 ,只有少数供医药用。随着养殖珍珠饰品业的大发展 ,珍珠及其饰品的质量问题也凸现出来了。具体地说 ,在珍珠饰品市场上 ,一些商人为了追求眼前利益 ,把一些劣珠或下等珍珠 ,通过加工变色、抛光和修饰后流入珍珠市场 ,蒙骗顾客当作好珠或上等项链出售。一些顾客 ,买了这些项链佩戴不久 ,珍珠层很快磨损 ,色彩很快消失。这种情况发生后 ,给整个珍珠市场以极大的冲击 ,所造成的影响也是难以估量的。解决这些问题的关键是抓好珍珠质量关。要抓好珍珠质量关…  相似文献   

9.
通过普通X-射线荧光光谱仪,结合PeakFit谱峰处理软件,对不同比例的MnO和MnO2的混合样品的Kβ谱峰参数进行了研究,用数学方法将实测的谱峰分解为各个单一的谱峰参数(峰位、峰高、半高宽、子峰面积),找出了各个谱峰参数与不同价态锰的含量之间的关系,并据此确定了中太平洋海山区大量富钴结壳样品中不同价态锰的相对含量.分析结果显示,富钴结壳中+4价锰从核心向外有增高的趋势,可以认为这与该区第三纪以来南极底流活动的增强有关.  相似文献   

10.
铜合金在海水中电化学阻抗谱特征研究   总被引:5,自引:0,他引:5  
利用电化学阻抗谱(EIS)对紫铜和铜镍合金在静止、洁净海水中表面成膜的过程进行了监测,根据不同阶段的EIS特征建立不同等效电路模型进行拟合分析。获得了铜合金基体及其表面膜层对应的界面电化学信息参数,通过比较3种金属(B10,TUP,B30)表面膜层随时间变化的差异。探讨了合金成分对表面成膜过程的影响。结果表明。浸泡前期B10和TUP的耐蚀性较差,但随着海水中浸泡时间增加,三者的耐蚀能力逐渐接近。TUP的EIS显示了其表面内、外膜层信息。B10表面膜层的成长速度和稳定性均不如B30,反映出合金中镍含量的增多,增加了铜镍合金表面成膜产生钝化的效应。  相似文献   

11.
This article reviews information recently available from existing marine and coastal mining for responses to environmental issues affecting marine mining at different depths. It is particularly but not exclusively concerned with those issues affecting seabed biodiversity impact and recovery. Much information has been gathered in the past 10 years from shallow mining operations for construction aggregate, diamonds, and gold, from coastal mines discharging tailings to shallow and deep water, and from experimental deep mining tests. The responses to issues identified are summarized in a series of eight tables intended to facilitate site-specific consideration. Since impacts can spread widely in the surface mixing layer SML, and can affect the biologically productive euphotic zone, the main issues considered arise from the depth of mining relative to the SML of the sea. Where mining is below the SML, the issue is whether it is environmentally better to bring the extraction products to the surface vessel for processing (and waste discharge), or to process the extraction products as much as possible on the seabed. Responses to the issues need to be sitespecific, and dependent on adequate preoperational environmental impact and recovery prediction. For deep tailings disposal from a surface vessel, there are four important environmental unknowns: (1) the possible growth of "marine snow" (bacterial flocs) utilizing the enormous quantities of fine tailings particles (hundreds or thousands of metric tons per day) as nuclei for growth, (2) the possibility that local keystone plankton and nekton species may migrate diurnally down to and beyond the depth of deep discharge and hence be subjected to tailings impact at depth, (3) the burrow-up capability of deep benthos and their ability to survive high rates of tailings deposition, and (4) the pattern and rate of dispersion of a tailings density current through the deep water column from discharge point to seabed. Actions to obtain relevant information in general and site-specifically are suggested.  相似文献   

12.
Particle fluxes were measured 7 m above the sea bottom during the predisturbance, disturbance, and postdisturbance periods by using time series sediment traps attached to seven deep-sea moorings deployed in the INDEX experiment site in the Central Indian Basin. The predisturbance particle fluxes varied between 22.3 to 55.1 mg m -2 day -1 . Increased and variable particle fluxes were recorded by the sediment traps during the disturbance period. The increase observed was 0.5 to 4 times more than the background predisturbance fluxes. The increases in particle fluxes (~4 times) recorded by the sediment trap located in the southwestern direction (DMS-1) were the greatest, which could be the result of preferential movement of resuspended particles generated during the deep-sea benthic disturbance along the general current direction prevailing in this area during the experimental period. Also, the traps located closer to the disturbance area recorded greater fluxes than did the traps far away, across the Deep Sea Sediment Resuspension System path. This variability in recorded particle fluxes by the traps around the disturbance area clearly indicates that physical characteristics such as grain size and density of the resuspended particles produced during the disturbance had an important effect on particle movement. The postdisturbance measurements during ~5 days showed a reduction in particle fluxes of ~50%, indicating rapid particle settlement.  相似文献   

13.
The interdependence between the seismo-acoustic properties of a marine sediment and its geotechnical/physical parameters has been known for many years, and it has been postulated that this should allow the extraction of geotechnical information from seismic data. Though in the literature many correlations have been published for the surficial layer, there is a lack of information for greater sediment depths. In this article, a desktop study on a synthetic seafloor model illustrates how the application of published near-surface prediction equations to subsurface sediments (up to several tens of meters burial depth) can lead to spurious predictions. To test this further, acoustic and geotechnical properties were measured on a number of sediment core samples, some of which were subjected to loading in acoustically-equipped consolidation cells (oedometers) to simulate greater burial depth conditions. For low effective pressures (representing small burial depths extending to around 10 meters subsurface), the general applicability of established relationships was confirmed: the prediction of porosity, bulk density, and mean grain size from acoustic velocity and impedance appears generally possible for the investigated sedimentary environments. As effective pressure increases through, the observed relationships deviate more and more from the established ones for the near-surface area. For the samples tested in this study, in some instances increasing pressure even resulted in decreasing velocities. There are several possible explanations for this abnormal behavior, including the presence of gas, overconsolidation, or bimodal grain size distribution. The results indicate that an appropriate depth correction must be introduced into the published prediction equations in order to obtain reliable estimates of physical sediment properties for greater subsurface depths.  相似文献   

14.
海上大直径钢管桩打桩过程中,桩周土体受到强烈扰动而发生强度弱化,掌握桩周土体强度弱化规律对于准确预测打桩过程、保证工程安全具有重要意义。为研究土体强度弱化规律,开展了环剪试验模拟打桩对桩周土体的扰动,测试土体强度随剪切速率的变化规律,建立了描述土体强度弱化规律的拟合公式,引入到打桩分析软件中。研究结果表明:土体的强度折减程度不仅与土体本身的性质有关还受到土体的埋深和剪切速率的影响,埋深越深土体强度折减程度越低,剪切速率越高土体强度折减越高,在打桩分析中可采用这里推荐的线性折减方法来模拟不同深度处土体强度的折减规律。  相似文献   

15.
The advanced piston corer (APC) has been used by the Ocean Drilling Program since 1985 for recovering soft sediments from the ocean floor. The pullout force measured on extracting the core barrel from the sediment is shown to correlate with the average shear strength of the sediment core measured in the ship's laboratory. A simple rule of thumb is derived relating the shear strength of the sediment to the pullout force. Multiple APC holes at individual sites allow the consistency of the pullout measurements to be assessed. The effects of different operational procedures during APC coring are also explored. Although generally applicable, the correlation between pullout force and laboratory measurements of shear strength breaks down for some APC holes, possibly because of the disturbance of some sediment types during the APC coring process. A better understanding of the physical process of APC coring, and its effect on the properties of the sediment both inside and immediately outside the core barrel, would indicate what confidence can be put on the measurement of pullout force as a way of evaluating the in situ shear strength of deep sea sediments.  相似文献   

16.
Specific properties of the interannual sea level variations and annual tides in the Northwestern Pacific were studied. Several tide stations were monitored. The monthly mean sea level for the year of 1995 was analyzed at each tide station. A seismic event in 1995, some tectonic activity around the subject area, and the Kuroshio (the oceanic western boundary current) may possibly contaminate results which would have occurred from the astronomical annual tide alone.  相似文献   

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《海洋学报(英文版)》2014,(11):161-F0003
<正>Acta Oceanologica Sinica(AOS)is a comprehensive academic journal edited by the Editorial Committee of Acta Oceanologica Sinica and is designed to provide a forum for important research papers of the marine scientific community which reflect the information on a worldwide basis.The journal publishes scholarly papers on marine science and technology,including physics,chemistry,biology,  相似文献   

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