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1.
马氏珠母贝（Pinctada martensii）是我国南方养殖的一种重要经济贝类，长期以来一直是我国主要的海水育珠的主要贝类，用马氏珠母贝育珠是广东、广西和海南沿海部分地区经济发展的支柱性产业。近年来，我国海水珍珠的质量出现明显滑坡，严重地削弱了在国际市场上的竞争力。为提高海水珍珠质量和在国际市场上的竞争力，国内科技工作者已经进行了大量的研究工作，这些工作主要包括对马氏珠母贝养殖群体性状的改良、育珠技术的优化和海水珍珠形成机理的研究。 相似文献
2.
<正>马氏珠母贝(Pinctada martensii)是我国南方养殖的一种重要经济贝类,长期以来一直是我国主要的海水育珠的主要贝类,用马氏珠母贝育珠是广东、广西和海南沿海部分地区经济发展的支柱性产业。近年来,我国海水珍珠的质量出现明显滑坡,严重地削弱了在国际市场上的竞争力。为提高海水珍珠质量和在国际市场上的竞争力,国内科技工作者已经进行了大量的研究工作,这些工作主要包括对马氏珠母贝养殖群体性状的改良、育珠技术的优化和海水珍珠形成机理的研究[1-5]。 相似文献
3.
This paper demonstrates an atmospheric correction method to process MODIS/Aqua (Moderate-resolution Imaging Spectroradiometer) ocean color imagery over turbid coastal waters with the aid of concurrent CALIOP (Cloud-Aerosol LIdar with Orthogonal Polarization) aerosol data, assuming that there exists "nonturbid" water in the study area where MODIS aerosol optical properties can be retrieved accurately. Aerosol properties from CALIOP measurements were obtained and related to those from MODIS. This relationship, combined with CALIOP aerosol data, was extended to turbid water to derive MODIS aerosol properties, where atmospheric correction using MODIS data alone often fails. By combining MODIS and CALIOP data, aerosol signals were separated from the total signals at the satellite level, and water-leaving radiances in turbid waters were subsequently derived. This method was tested on several MODIS/Aqua ocean color images over South China turbid waters. Comparison with field data shows that this method was effective in reducing the errors in the retrieved water-leaving radiance values to some extent. In the Zhujiang (Pearl) River Estuary, this method did not overestimate the aerosol effects as severely, and provided far fewer negative water-leaving radiance values than the NASA (National Aeronautics and Space Administration) default methods that used MODIS data alone. 相似文献
4.
Empirical ocean color algorithm for estimating particulate organic carbon in the South China Sea 总被引：1，自引：0，他引：1
We examined regional empirical equations for estimating the surface concentration of particulate organic carbon(POC) in the South China Sea. These algorithms are based on the direct relationships between POC and the blue-to-green band ratios of spectral remotely sensed reflectance,R rs( λ B)/ R rs(555). The best error statistics among the considered formulas were produced using the power function POC(mg/m 3)=262.173 [ R rs(443)/ R rs(555)]- 0.940. This formula resulted in a small mean bias of approximately-2.52%,a normalized root mean square error of 31.1%,and a determination coefficient of 0.91. This regional empirical equation is different to the results of similar studies in other oceanic regions. Our validation results suggest that our regional empirical formula performs better than the global algorithm,in the South China Sea. The feasibility of this band ratio algorithm is primarily due to the relationship between POC and the green-toblue ratio of the particle absorption coefficient. Colored dissolved organic matter can be an important source of noise in the band ratio formula. Finally,we applied the empirical algorithm to investigate POC changes in the southwest of Luzon Strait. 相似文献
5.
Comparison of growth and survival of larvae among different shell color stocks of bay scallop Argopecten irradians irradians（Lamarck 1819） 总被引：8，自引：0，他引：8
In order to improve production and breed new broods of bay scallop Argopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass spawning at a commercial scallop hatchery in spring, 2002. And then larval growth and survival of different lines was compared to test whether there is a relationship between shell color and growth and survival at early developmental stage. Both growth and survival have no significant differences among different experimental larvae of self-fertilization or mass spawning. Results are as following in the order of orange, purple and white shell stock. For the self-fertilization, growth rates of larvae were 6.174, 6.412, and6.599 μm/d, respectively. Survival rates of larvae at Day 3 were 74.41%, 76.86%, and 82.05%; Day 6 were 49.14%, 65.63%, and 52.79%; and Day 9 were 25.06%, 20.80%, and 26.47%, respectively. For the mass spawning, the growth rates were 7.836, 7.941, and 7.878 μm/d, respectively. Survival rates at Day 3 were 93.05%,91.95%, and 92.50%; Day 6 were 79.17%, 78.05%, and 82.50%; and Day 9 were 34.72%, 36.67%, and 38.33%,respectively. The absence of any relationship between shell color and growth and survival at the larval stage may be resulted from their common genetic basis. 相似文献
6.
In order to improve production and breed new broods of bay scallopArgopecten irradians irradians, different-colored orange, purple and white lines were established by two mating methods of self-fertilization and mass spawning
at a commercial scallop hatchery in spring, 2002. And then larval growth and survival of different lines was compared to test
whether there is a relationship between shell color and growth and survival at early developmental stage. Both growth and
survival have no significant differences among different experimental larvae of self-fertilization or mass spawning. Results
are as following in the order of orange, purple and white shell stock. For the self-fertilization, growth rates of larvae
were 6.174, 6.412, and 6.599 μm/d, respectively. Survival rates of larvae at Day 3 were 74.41%, 76.86%, and 82.05%; Day 6
were 49.14%, 65.63%, and 52.79%; and Day 9 were 25.06%, 20.80%, and 26.47%, respectively. For the mass spawning, the growth
rates were 7.836, 7.941, and 7.878 μm/d, respectively. Survival rates at Day 3 were 93.05%, 91.95%, and 92.50%; Day 6 were
79.17%, 78.05%, and 82.50%; and Day 9 were 34.72%, 36.67%, and 38.33%, respectively. The absence of any relationship between
shell color and growth and survival at the larval stage may be resulted from their common genetic basis.
This work was financially supported by Project of Scientific Innovation, Chinese Academy of Sciences (ZKCX2-211). 相似文献
7.
Yan Xinghong 《中国海洋湖沼学报》1993,11(3):235-244
Isolated protoplasts from thalli ofPorphyra haitanensis andPorphyra yezoensis were treated with colchicine or irradiated by ultraviolet (UV). Several types of color variants were observed among the protoplast
offspring. After treatment with colchicine: (1) 0.04–0.09% of red type variants inP. haitanensis were obtained; (2) The rate of red type variants and the variegated chimeral thalli composed of red type and wild type of
sectors were 0.31–1.11% inP. yezoensis. After irradiation with UV: (1) 3.5–10.5% of red type variants inP. yezoensis were obtained: (2) 0.5–2.0% of red type variants and the variegated chimeral thalli composed of red type and wild type of
sectors were obtained inP. haitanensis. Colchicine and UV’s mutangenic effects onP. yezoensis protoplasts were stronger than those onP. haitanensis protoplasts. The most efficient concentration of colchicine was 0.05%. The optimal length of UV-radiation was 1/2 min (radiation
distance 5 cm). The red type variants induced by colchicine treatment grew faster than the wild type thalli. The clones of
vegetative propagation from protoplasts of red type variants were still red type thalli. The red type variants will be good
materials for genetic studies and improvement ofPorphyra strains. 相似文献
8.
This study showed that the combined effect of absorption of planktonic algae and water on water color shift can be simulated
approximately by the exponential function: Log(E
100cm
W
+E
100cm
Xch1
)=0.002λ−2.5 whereE
100 cm
W
,E
100cm
Xchl
are, respectively, extinction coefficients of seawater and chlorophyll—a (concentration is equal toX mg/m3), and λ (nm) is wavelength.
This empirical regression equation is very useful for forecasting the relation between water color and biomass in water not
affected by terrigenous material. The main factor affecting water color shift in the ocean should be the absorption of blue
light by planktonic algae. 相似文献
9.
地形颜色渐变渲染是表达地形起伏变化或其他地学要素空间分布变化趋势的常用方法。在三维地学交互分析系统中观察分析三维地学信息时,需要依据观察位置和分析区域的范围大小不停地变化视角和视距。当观察距离很近时,利用包含一定颜色数的色带渲染地形会出现明显的颜色分层现象,不能很好地表达地形颜色的光滑过渡。针对三维地学交互分析系统对地形颜色渐变渲染的操作需求和存在的问题,分析了RGB和HSL两种颜色模型的特点,顾及OpenGL的颜色平滑过渡原理,在RGB颜色空间通过对所有颜色分量进行线性插值实现了地形双色渐变渲染,在HSL颜色空间通过固定饱和度、亮度,对色相进行线性插值实现了地形多色渐变渲染,并通过加入光照计算来增强地形颜色渐变晕渲的三维立体效果。实验结果表明：本文方法能很好地兼容OpenGL的平滑着色,实现三维交互环境下任意距离观察地形均能保持颜色之间光滑渐进过渡,达到更为光滑的地形颜色渐变渲染效果。 相似文献
10.
In-situ data from cruises in the Pearl River estuary and adjacent marine areas were collected during March to May 2001. The absorption coefficients of the water color components were studied in detail containing total suspended matter (TSM), chlorophyll-a (chl-a), colored dissolved organic matter (CDOM), and de-pigment particles. For absorption coefficient of TSM, ap, and that of de-pigment particles, ad, correlations of ap(440)-TSM, ad(440)-TSM, ap(440)-chl-a and ad-chl-a were done (the italicized term means the concentration). There was a good correlation between ap(440) and chl-a concentration. An empirical relationship model between aph(675) and chl-a was developed showing a strong correlation of 0.93. Based on the two models the chl-a and aph(λ) were correlated. The values of calculated empirical spectral slope for CDOM absorption coefficients and that of de-pigment particles, 0.017 0 and 0.011 6 respectively, both are within a relative standard error of 10.0%. 相似文献
11.
Palaeosols associated with fluvial of the Siwalik Group are and lacustrine deposits that occur as thick multiple pedocomplexes. The bright red color of the palaeosol beds has been earlier interpreted as a result of hot and arid palaeoclimate. However, as against this view, our investigations of the bright red palaeosol beds of the Lower Siwaliks suggest that the climate was cool and subhumid, instead of hot and arid during the deposition of these beds. Since cold climate is not very conducive to impart red coloration, further research is needed to explain the cause of these red beds. For this, the micromorphological study of soil thin sections was done which showed the presence of features such as dissolution and recrystallisation of quartz, feldspar and mica, compaction, slickensides, presence of calcite spars, subrounded and cracked nature of quartz grains, microfabric, complex patterns of birefringence fabrics, pigmentary ferric oxides, thick cutans and cementation by calcite. These features indicate that diagenesis took place on a large scale in these sediments. The positive Eh and neutral-alkaline pH of soils also suggest that the conditions were favorable for the formation of diagenetic red beds. During burial diagenesis of sediments, the hydroxides of ferromagnesian minerals got converted into ferric oxide minerals （hematite）. During deep burial diagenesis smectite was converted into illite and the preponderance of illite over smectite with increasing depth of burial also indicates the diagenesis of sediments. Thus, the red color of the Lower Siwalik palaeosols seems to be due mainly to the burial diagenesis of sediments and does not appear to be due to the then prevailing climatic condition. 相似文献
12.
13.
根据体侧纵带颜色差异,暂将画眉笛鲷(Lutjanus vitta)分为黄带画眉笛鲷和褐带画眉笛鲷,应用RAPD技术,选用22个引物对黄带画眉笛鲷与褐带画眉笛鲷进行遗传多样性及分子标记研究。结果表明,黄带画眉笛鲷与褐带画眉笛鲷的遗传距离为0.832 9,其多态位点比例(P)分别为66.99%和85.28%,遗传多样性指数(H)分别为0.161 7和0.289 3,种内遗传距离(D)分别为0.243 5和0.431 9,表明褐带画眉笛鲷的遗传多样性比黄带画眉笛鲷丰富。共得到OPP14-629bp和OPP14-674bp等11个特异性分子标记,可用于两种笛鲷的鉴定。 相似文献
14.
产于玄武岩中的蓝宝石颜色通常较深 ,山东昌乐蓝宝石的颜色因其晶体巨大更显得深暗。这类蓝宝石曾多次进行过改色试验 ,但成效都不大。通过对电子探针及紫外—可见光—近红外吸收光谱图测试结果的分析 ,并对山东昌乐蓝宝石的颜色与化学成分之间的关系进行研究 ,结果表明 :昌乐蓝宝石的主要致色元素为Fe,Ti,Cr,Ni等 ,Fe2 O3 FeO含量高及TiO2含量少 ,以及成对Fe3 的大量存在是其颜色偏深的重要原因 ;TiO2 含量对蓝宝石颜色纯度影响很大 ,也是蓝宝石改色能否成功的重要因素之一。 相似文献
15.
受植被时相变化、传感器畸变、获取时刻大气条件等因素的影响,不同时间获取的遥感影像存在色彩差异,而逐波段的色彩归一化容易引起新的色彩畸变。因此,本文提出一种复合类别支持的多元线性回归遥感影像色彩归一化方法,在输入影像和参考影像逐波段高斯归一化的基础上,进行复合聚类,确定各像元的复合类别;在迭代去除变化像元的基础上,将类别中心作为控制点,建立多元线性回归方程,并据此对输入影像进行处理。2组影像的试验结果表明,本文方法相对于传统方法在整体精度、色彩保持等方面具有较大的优势。 相似文献
16.
绿松石呈色的晶体场理论计算 总被引：1，自引：1，他引：0
绿松石中Cu^2 电子组态为3d^9,为中心对称配位八面体，配位体为4个OH^-和2个H2O，在晶体场作用下，五重简并的d轨道分裂为5个能量不同的轨道，dx^2-y^2为基态，其余为激发态，依跃迁选律．从基态到四个激发态的跃迁为自旋允许跃迁，从而形成了铜离子吸收光谱的4条谱带。前人对绿松石中Cu^2 晶体场势能计算时，个别系数有误，笔者进行了修改，并补充了部分角度函数的积分值，从而使结果得到了改进，计算谱带位置与实测可见光吸收光谱谱带位置十分接近。在进行晶体场势能计算时，角度函数积分值是非常重要的，以往的资料只是直接给出了部分积分值，这在计算低对称配位八面体晶体场势能时是不够的，这次重新计算了所有可能的角度函数积分值，对各种对称下配位八面体晶体场能量的计算提供了可能。 相似文献
17.
XIU Peng LIU Yuguang 《中国海洋大学学报(英文版)》2006,5(3):213-218
Based on the in situ optical measurements in the Bohai Sea of China, which belongs to a typical case-2 water area, we studied the characteristics of DCM （deep chlorophyll maximum） such as its spatial distribution, vertical profile, etc. We found that when the depth of the chlorophyll maximum is comparatively small, even in turbid coastal water regions, there is always a good correlation between the concentrations of chlorophyll maximum and the satellite-received signals in blue-green spectral bands; the correlation is even better than that between the surface chlorophyll concentrations and the satellite-received signals. The strong correlation existing even in turbid coastal water regions indicates that an ocean color model to retrieve the concentration of DCM can be constructed for coastal waters if a comprehensive knowledge of the vertical distribution of chlorophyll concentration in the Bohai Sea of China is available. 相似文献
18.
在雾天情况下,室外采集到的图像易受到噪声干扰,质量降低,清晰度下降。在对常用的几种图像去雾方法的对比分析及研究的基础上,提出了改进的基于小波变换结合暗原色先验去雾的快速算法。通过小波分解可求出近似环境光,对环境光,大气光的估计,可对原图像进行复原。实验表明,改进的算法不但去雾效果明显,图像色彩丰富,而且可以有效地减少运行时间,提高运行速度。 相似文献
19.
颜色是珠宝玉石宝石学特征研究的重要一项,是影响宝玉石价值的重要因素。泰山玉有4个颜色系列,对各系列泰山玉致色因素的分析研究具有重大意义。通过化学分析和电子探针测试,查明了泰山玉的主要化学成分,对比分析了化学成分与颜色的关系,最终确定了不同颜色系列泰山玉的致色因素。 相似文献
20.
华贵栉孔扇贝两种壳色群体生长和消化酶活力比较 总被引：2，自引：0，他引：2
以华贵栉孔扇贝桔黄和紫褐壳色个体为亲本建立两个壳色群体,从壳长、壳高、壳宽和体重几方面进行生长比较,并对两个群体做了淀粉酶和纤维素酶活力比较。结果表明:桔黄壳色群体的平均壳长、平均壳高、平均壳宽和平均体重显著大于紫褐壳色群体(P<0.05)。在24℃、27℃、30℃和33℃条件下,桔黄壳色群体的淀粉酶和纤维素酶活力显著高于紫褐壳色群体(P<0.05);不同壳色群体生长与其淀粉酶和纤维素酶活力有关。 相似文献