基于G0分布的SAR图像水边线提取方法

为了更加精准地从合成孔径雷达（SAR）图像中提取水边线,提出基于G0分布的SAR图像水边线提取方法。首先,将SAR图像域划分为大小相等的子块,并假设每个子块内像素强度服从独立同一的G0分布;利用矩估计方法得到对应每个子块的粗糙度和散射性参数;根据设定的参数阈值,可划分出粗略的水域,并确定该区域的几何中心;以该几何中心为圆心,向四周做射线,保留经过陆地区域的射线;利用似然函数确定每条射线上的水-陆分界点,依次连接分界点,进而实现SAR图像水边线提取。采用本文方法,分别对模拟和真实SAR图像进行水边线提取实验。定性和定量结果表明：采用基于G0分布的SAR图像水边线提取方法能够有效地克服斑点噪声的影响。     

Generating ground motion by two new techniques of adding harmonic wave in the time domain and approximating to response spectrum as a whole

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Extended structures around yso in Mid-IR broad emission features

We present CO(1-0) observations toward the soft gamma-ray repeater SGR 1806-20. We discuss the implications on the distance to the X-ray counterpart: AX 1805.7-2025. We also present an upper limit at = 1.3 mm for the thermal emission from dust and high resolution IRAS maps of the region. SGR 1806-20 is very likely associated with the H II complex W31. The G10.0-0.3 supernova remnant (SNR) could be expanding in the very low density region produced by the wind of the bright O9-B2 star recently detected.National Academy of Sciences / National Research Council Resident Research Associate     

几种鳕鱼的生物学初步研究

本文在调查与校核资料的基础上，报告了狭鳕（Theragra chalcogramma)、蓝鳕（Micromesistius poutassou)、远东宽突鳕（Eleginus gracilis)、大西洋鳕（Gadus morhua)、太平洋鳕（Gadus macrocephalus)和黑线鳕（Melanogrammus aeglefinus)等六种经济鳕雪类分类地位、区系性质与分布。并对上述鳕雪主要形态特征进行了详细的描述，建立了狭鳕等五种鳕鱼体长与总重关系式，以期找出各鱼种的生长发育规律。     

分段多项式风浪频谱

本文分两段、三段、四段给出多项式形式的风浪频谱，它们满足下述条件：分段处谱值及斜率均连续；谱峰位于给定点（ωｏ，ｐ）；谱矩与有效波高Ｈ，平均周期Ｔ之间满足关系式Ｈ＝４．０√ｍ０，Ｔ＝２π（ｍ０／ｍ１）或Ｔ＝２π√ｍ０／ｍ２。多项式谱的指数和分段点均是可变的，因而谱形可在较大范围内调整，以便拟合实测谱和各种不同形式的谱。文中给出用四段多项式谱拟合ＪＮＳＷＡＰ谱的实例。     

Raman Quantitative Measurements for Carbon Isotopic Composition in CO2-Rich Fluid Inclusion: A Preliminary Study

Carbon dioxide is a common and important component in fluid inclusions. Because carbon isotopic ratio of CO₂ in fluid inclusion can provide geochemical characteristics of source rocks, many works have been conducted to measure the carbon isotopic ratio (¹³C/¹²C) of CO₂. In general, carbon isotopic composition (¹³C/¹²C) of CO₂ fluid inclusions are measured by mass spectroscopy. However, mass spectroscopy is a destructive analytical technique, and can not be applied to measure single inclusion. Raman spectroscopy is an efficient non-contact and non-destructive method, and has been widely employed in many research fields. In fact, due to the difference of carbon atom mass, the Femi resonance of ¹³CO₂ is lower than that of ¹²CO₂, so they can be identified in Raman spectrum. In principle, the carbon isotopic composition (¹³CO₂/¹²CO₂) in CO₂ is closely related to the Raman intensity ratio between ¹³CO₂ and ¹²CO₂ (I+13/I+12). Therefore, Raman spectroscopy can theoretically be utilized to measure the carbon isotopic composition (¹³CO₂/¹²CO₂) of CO₂. However, this method is seriously hampered by the poor measurement accuracy and precision. In this study, based on the theoretical analysis, and in combination with previous Raman studies on carbon isotopic composition in CO₂, a preliminary research on Raman quantitative measurement for carbon isotopic composition in CO₂ was carried out.     

致密油分布的沉积相控作用分析:以齐家地区高台子油层为例

为了找出齐家地区高台子油层致密油分布的控制因素,通过精细的沉积解剖特征研究,认为齐家地区高三、高四油层组沉积相为浅水三角洲相,由北向南依次发育三角洲平原-三角洲前缘-前三角洲亚相,基准面下降期间伴随多次小规模的湖进造成三角洲外前缘与前三角洲泥,三角洲内前缘前端与三角洲外前缘泥岩呈多期迭加分布,给源内致密油提供了源储匹配的前提。其次,分析了沉积相对致密储层、优质生油层及两者匹配关系这"三大条件"的控制作用,指出齐家地区存在两种致密油藏:三角洲内前缘前端远砂坝致密油藏和三角洲外前缘席状砂致密油藏。通过比较"三大条件"的优劣程度,认为前者储层条件、烃源岩条件及源储匹配较好,是本区最重要的致密油藏类型。最后指出齐家南部外前缘前端远砂坝微相是下一步致密油勘探的最有利微相。     

应用电子微探针-扫描电镜-拉曼光谱-电子背散射衍射研究一种未知Ti-Zr-U氧化物的矿物学特征

本文应用电子微探针(EPMA)、扫描电镜(SEM)在阿尔金地区的榴闪岩中发现了一种微米级含铀氧化物矿物,结合光学显微镜、拉曼光谱和电子背散射衍射(EBSD)技术对该矿物的化学成分、赋存状态、物理及光学性质、晶体结构等矿物学特征进行了研究。结果表明,该矿物在空间上与钛铁矿关系密切且主要产于其边部,为一种不透明矿物;主要化学组成为TiO2、ZrO2和UO2,实验化学式为(Zr,U)Ti2O6,其中U与Zr互为类质同象替代;具独特的拉曼光谱特征,初步确定为斜方晶系且具有序的铌钙矿结构。通过电子微探针U-Th-Pb定年获得等时线年龄为451±49Ma,可能代表了寄主岩石的退变质年龄。将该矿物与化学成分类似的晶体进行对比,发现与斯里兰卡石等已知天然矿物存在差异,而与一种人工合成晶体Zr5Ti7O24在化学成分和晶体结构上较为相似,可以初步推断Ti-Zr-U氧化物为一种未被人们发现的新矿物。     

Crystallization behavior of Na2SO4–MgSO4 salt mixtures in sandstone and comparison to single salt behavior

We report on the crystallization behavior and the salt weathering potential of Na₂SO₄, MgSO₄ and an equimolar mixture of these salts in natural rock and porous stone. Geochemical modeling of the phase diagram of the ternary Na₂SO₄–MgSO₄–H₂O system was used to determine the equilibrium pathways during wetting (or deliquescence) of incongruently soluble minerals and evaporation of mixed electrolyte solutions. Model calculations include stable and metastable solubilities of the various hydrated states of the single salts and the double salts Na₂Mg(SO₄)₂·4H₂O (bloedite), Na₂Mg(SO₄)₂·5H₂O (konyaite), Na₁₂Mg₇(SO₄)₁₃·15H₂O (loeweite) and Na₆Mg(SO₄)₄ (vanthoffite). In situ Raman spectroscopy was used to study the phase transformations during wetting of pure MgSO₄·H₂O (kieserite) and of the incongruently soluble salts bloedite and konyaite. Dissolution of kieserite leads to high supersaturation resulting in crystallization of higher hydrated phases, i.e. MgSO₄·7H₂O (epsomite) and MgSO₄·6H₂O (hexahydrite). This confirms the high damage potential of magnesium sulfate in salt damage of building materials. The dissolution of the incongruently soluble double salts leads to supersaturation with respect to Na₂SO₄·10H₂O (mirabilite). However, the supersaturation was insufficient for mirabilite nucleation. The damage potential of the two single salts and an equimolar salt mixture was tested in wetting–drying experiments with porous sandstone. While the high damage potential of the single salts is confirmed, it appears that the supersaturation achieved during wetting of the double salts at room temperature is not sufficient to generate high crystallization pressures. In contrast, very high damage potentials of the double salts were found in experiments at low temperature under high salt load.1     

不同压力下Ⅰ型甲烷水合物拉曼光谱

本文描述了合成的Ⅰ型甲烷水合物高压下拉曼光谱测定结果。甲烷水合物用细粒冰和甲烷气在温度0℃～9℃和压力18MPa下历时2天合成,在金刚石压腔里进行了原位的显微观察和拉曼光谱测定。一组温度25℃和压力范围132～901MPa下的拉曼光谱数据显示,样品的光谱呈左高右低的双峰结构,左谱峰位置范围为2904.4～2907.2cm~(-1),右谱峰位置范围为2915～2922cm~(-1),谱峰位置随压力变化,典型光谱的左右谱峰强度比近似为3:1,系典型的Ⅰ型结构特征;这说明甲烷水合物在较高压力下也能保持Ⅰ型结构。作为比较,甲烷气和溶解水中的甲烷的拉曼光谱也进行了测定,它们的拉曼光谱特征与Ⅰ型甲烷水合物的明显不同。