海底地下水排泄及其对沿海海域生态环境的潜在影响

海底地下水排泄(SGD)是海岸带陆海相互作用的一个重要的自然过程.系统介绍SGD的发生过程及其定量测定的方法,并通过水文计算和野外调查,在估算了区域海底地下水排泄量和分析了海水与地下水中氮、磷、碳等营养物质差异的基础上,讨论了SGD对近海海域生态环境的潜在影响,这对正确区分近岸海域营养物质的来源和认识中国沿海水域频繁发生的赤潮藻暴发性增殖事件的原因,具有重要的理论和实践意义.     

Brightness Temperature Emitted by Radiometer Calibration Load at Millimeter Wave Band

In this paper, the DVRT (vector radiative transfer theory of densely distributed random discrete scatters) model to calculate the brightness temperature emitted by radiometer calibration load is presented. It takes the multiple scattering of isolation layer into account, which is neglected by the incoherent homogeneous model often used in calibration. Hence, it works much better than incoherent homogeneous model at millimeter wave band. Furthermore, the iteration of DVRT model is presented, and it proves that the incoherent homogeneous model is just the zero-order solution of DVRT model. Some numerical results are provided in the end.     

导热泥强化传热作用的数值模拟

本文对于导热泥在输运沥青等粘稠物质中的强化传热作用进行了数值模拟。计算中采用直角坐标系下的区域扩充法处理不规则的边界,时间项离散采用全隐格式,导热泥表面辐射热流按附加源项法处理。计算表明,采用导热泥强化了传热,完全可以替代蒸汽套管加热方式。     

Segmentation of Pulmonary Nodule Images Using 1-Norm Minimization

Total variation minimization (in the 1-norm) has edge preserving and enhancing properties which make it suitable for image segmentation. We present Image Simplification, a new formulation and algorithm for image segmentation. We illustrate the edge enhancing properties of 1-norm total variation minimization in a discrete setting by giving exact solutions to the problem for piecewise constant functions in the presence of noise. In this case, edges can be exactly recovered if the noise is sufficiently small. After optimization, segmentation is completed using edge detection. We find that our image segmentation approach yields good results when applied to the segmentation of pulmonary nodules.     

闪光辐射照相及光学高速摄影图象的增强处理

本文介绍图象增强处理技术在闪光辐射照相图象及光学高速摄影图象中的应用.针对闪光图象及高速摄影图象的特点,研究了一些有效的图象增强方法,取得了很好的应用效果. 文中给出了部分应用实例.     

钴的表面增强拉曼散射中的电磁增强因子计算

本文初步探讨了钴电极的表面增强拉曼散射机理。采用二维阵列理论模型在 0 .5～ 4.0eV的光子能量范围对钴纳米椭球阵列的表面增强拉曼散射 (SERS)现象进行了理论分析。有关计算表明 ,经过合适的表面粗糙化的钴金属电极能产生较弱的表面增强效应 (SERS增强因子约 1 0 2 ～ 1 0 4 ) ,制备出具有高纵横比的纳米粒子阵列是得到钴体系较大的SERS增强因子的关键     

SEPARABILITY OF SPECIFIC VOLUME IN THERMODYNAMIC EQUATION OF STATE

A type of system, in which the specific volume can be divided into several parts according to its Hamiltonian, has been obtained in a grand ensemble. The main character of such a system is that its Hamiltonian is absolutely separable. We also discuss the partial specific volume contributed by thermoelectrons in metals under a free-interaction approximation, and the corresponding Wu－Jing parameter is obtained as a simple example.     

CRYSTAL STRUCTURE AND MAGNETIC PROPERTIES OF La1.2Sr1.8-xCaxMn2O7

The effect of divalent cation substitution on the structure and magnetic properties of La_1.2Sr_1.8-xCa_xMn₂O₇ (x = 0－0.900) is investigated in this paper. Partly replacing divalent cation Sr²⁺ by Ca²⁺ ions results in the weakening and then disappearance of long-range ferromagnetic ordering, and the formation of spin canting and low-temperature spin-glass. Based on structural analysis by Rietveld profile fitting, we suggest that this variation of magnetic property be related to a Jahn－Teller-type attice distortion of MnO₆ octahedra due to the introduction of the smaller sized Ca²⁺ ions.     

NEW EXPLICIT AND EXACT TRAVELLING WAVE SOLUTIONS FOR A COMPOUND KdV－BURGERS EQUATION

In this paper, new explicit and exact travelling wave solutions for a compound KdV－Burgers equation are obtained by using the hyperbola function method and the Wu elimination method, which include new solitary wave solutions and periodic solutions. Particularly important cases of the equation, such as the compound KdV, mKdV－Burgers and mKdV equations can be solved by this method. The method can also solve other nonlinear partial differential equations.     

多元校正模型用于拼色食品中混合色素的同时测定

采用多元校正模型,不经分离,用吸光光度法同时测定拼色食品中混合合成色素,获得较满意的结果,同时对影响实际样品分析的因素进行了探讨。