溴素的有机化学──I．2，4，6－三溴苯甲酸溴代和非溴代芳酯的合成

用ｍ－氨基苯甲酸作原料，经溴代、重氮化、还原脱氨、酰氯化和酯化反应等步骤，合成了六种新型的三溴苯甲酸的溴代和非溴代芳酯，即；双（２，４，６－三溴苯甲酸）－２＇，３＇，５＇，６＇－四溴－１＇，４＇－苯二酯，２，４，６－三溴苯甲酸－２＇，３＇，４＇，５＇，６＇－五溴苯酯，２，４，６－三溴苯甲酸－２＇，４＇，６＇－三溴苯酯，２，４，６－三溴苯甲酸－４＇－溴苯酯，２，４，６－三溴苯甲酸－４＇－甲基苯酯和２，４，６－三溴苯甲酸苯酯．通过对产物中碳、氢、溴元素的定量分析以及红外吸收光谱和氢核磁共振谱的研究，验证了合成产物的结构。     

袁长津治疗新型冠状病毒感染后咳嗽经验

介绍袁长津教授治疗新型冠状病毒感染后咳嗽的临床经验。袁教授在精研中医典籍的基础上，结合临床经验，认为新型冠状病毒感染后咳嗽的基本病机为感染后期余邪未尽，正气受伤；痰热未清，肺阴受损，肺之宣发肃降功能受到影响，导致肺气上逆，发为咳嗽。本病虽涉及脾肾，但总归病位于肺，又肺为娇脏，用药不宜峻猛，故袁教授在临证治疗过程中，往往用药平和，力求达到治病求本的目的。并附验案2则，以资佐证。     

哥德堡变奏曲：童话之城，日不落

“卡片的邮戳来自北欧的问候，知道你在地球的那头，心已飞向北半球，听说那里的冬天从来没白昼。”冬天没白昼，所以，夏天日不落……至今我仍清晰地记得，飞机在斯京降落的时候云蒸霞蔚，一道从天空射下的彩虹穿越云层。我们穿云而行，仿佛会融化在那道彩虹里，胜似穿越，因为每一刻都是崭新的。     

主编手记

鲨鱼是让人类又爱又恨的物种之一。为什么这么说？道理很简单。说起鲨鱼，我们能想到很多，有关探险，有关美食，有关好莱坞电影，也有关海滨灾难。生活在海洋中的鲨鱼，处于海洋生物食物链的顶级，也就是说，除了人类以外，很少有其他的海洋生物物种能够对它的生存造成直接的威胁。顶级生物的数量一般都比较少，往往给人一种“离群索居”的印象，鲨鱼也是这样，它们就像是生活在深海中的冷漠杀手一样，悄无声息地在海水中逡巡，所到之处，所有弱小的鱼儿仓皇逃窜。     

主编手记

金秋十月，新中国迎来60华诞。这60年中，一个国家，几代人，经历了激动人心的奋战，崎岖坎坷的抗争，埋头苦干的自省，以及昂首阔步的前行。     

左宗棠的海防思想（上）

鸦片战争期间，左宗棠虽然地位低微，却密切注视着时局的发展。1840年英军进犯广州城时，他就提出了歼敌于广州的三点建议：一是扼守险要，围困敌人；二是封锁海口，坚壁清野；三是招募水勇，动员民众。当时，他的意见难以产生什么影响，直到20年后，左宗棠任封疆大吏时，才有将其思想变为现实的可能。在晚清的两次海防大讨论中，左宗棠作为朝廷重臣和封疆大吏，针对中国海防危机的日益加深和西方国家从海上的频繁入侵，在主张加强西北边疆塞防的基础上，提出了一系列海防思想。     

科学的力量：设计你心仪的狗狗

如果可以设计一只完美狗狗，你想让它是什么样子？大的，小的，软毛的，硬毛的，黑的，白的？对于宠物买家而言，狗狗的相貌和性格同样重要。澳大利亚莫纳什大学的保利·贝内特博士表示，可以将科学和培育结合起来，根据需要培养出具备一定特质的狗狗，使其更好地适应家养环境。贝内特博士说：“犬科动物的行为特征是可遗传的，理论上我们可以固定那些想要的特质并使之遗传下去，     

赵瑞华以虚为本辨治产后病经验

介绍赵瑞华教授以虚为本辨治产后病的经验。赵教授在产后病“多虚多瘀”病机的基础上，提出其病机为多虚兼瘀，认为虚是产后病的核心因素，瘀是继发于虚的衍生因素，治则治法以扶正培元、顾护脾胃为主，佐以治瘀，兼以祛邪，注重调畅情志，临床多以当归补血汤为基础方，临证灵活化裁，病证结合，合方应用，用药稳中求变，平中求奇，临床疗效显著。并附验案1则，以资佐证。     

沈葆桢的海防思想（下）

沈葆桢十分清楚日本的外强中千。1874年8月，他清醒地指出：“倭营貌为整暇，实有不可终日之势”；“虽勉强支撑，绝不能久也”。沈葆桢认识到，“要之，倭将非不知难思退，而其主思贫成虐，不惜以数干兵为孤注，谣言四布，冀我受其恫喝，迁就求和”，倘若落入日本的圈套，其“必得一步又进一步，此皆屡试屡验之覆辙”。     

出网银刀乱——银鱼

银鱼在鱼类分类上属于鲑形目．银鱼科。它们分布于山东至浙江沿海的长江、珠江等河流的入海处，尤以鄱阳湖，长江口崇明等地为多，江苏太湖也盛产。银鱼种类有15种之多，如尖头银鱼（Salanx acuticeps）、白肌银鱼（Leucosoma chinensis）、短尾新银鱼（Neosalanx tangkahkeii）。尖头银鱼体细长，约27厘米，前部平扁，后部较高，吻尖突，两颌等长，各具一行犬牙，具假鳃，体无鳞，雄鱼臀鳍上方具一纵行大鳞片，体色银白，半透明，尾鳍有黑点，     

Hyperbolic Mild Slope Equations with Inclusion of Amplitude Dispersion Effect: Random Waves

New hyperbolic mild slope equations for random waves are developed with the inclusion of amplitude dispersion. The frequency perturbation around the peak frequency of random waves is adopted to extend the equations for regular waves to random waves. The nonlinear effect of amplitude dispersion is incorporated approximately into the model by only considering the nonlinear effect on the carrier waves of random waves, which is done by introducing a representative wave amplitude for the carrier waves. The computation time is greatly saved by the introduction of the representative wave amplitude. The extension of the present model to breaking waves is also considered in order to apply the new equations to surf zone. The model is validated for random waves propagate over a shoal and in surf zone against measurements.     

THE NONLINEAR INTERNAL GRAVITY WAVES IN STRATIFIED FLUID

In this paper, starting from the equations of the nonlinear internal gravity waves in stratified fluid, using the method of the Taylor expansion nearby the equilibrium point for the nonlinear terms, we find the analytical solutions for nonlinear internal gravity waves. The linear internal gravity waves and solitary waves are its special cases. The nonlinear internal gravity waves satisfy the well-known KdV (Karteweg-de Vries) equation. The nonlinear internal gravity waves are different from linear waves in character. The former dispersive relation contains the amplitude, but the latter does not. The larger the amplitude and the wavelength the faster are waves for the nonlinear internal gravity waves. The smaller the stability of the stratification, the larger is the wavelength (or the width). Some phenomena such as squall line, cumulus, turbulent mass structure in atmosphere, and thermocline in ocean have these natures.     

Normalization of Hydrodynamic Coefficients in Morison Equation

-The hydrodynamic coefficients C_d and C_m are not only dependent on the size of slender cylin-der,its location in water,KC number and Re number,but also vary with environmental conditions,i.e.,in regular waves or in irregular waves,in pure waves or in wave-current coexisting field.In this paper,thenormalization of hydrodynamic coefficients for various environmental conditions is discussed.When aproper definition of KC number and proper characteristic values of irregular waves are used,a unified re-lationship between C_d,C_m and KC number for regular waves,irregular waves,pure waves and wave-cur-rent coexisting field can be obtained.     

Transparent boundary condition for simulating nonlinear water waves by a particle method

Open boundaries are important when simulating water waves. In this study, a transparent boundary condition at an open boundary was developed for simulating nonlinear water waves propagating to a distant area using the Moving Particle Semi-implicit method. The novelty of this study is that the technique of wave analysis used in the experiment was introduced into the particle simulation to absorb incident waves; the simulation cost was reduced by employing inflow and outflow regions instead of a long dissipation region. Incident waves in front of the boundary were evaluated using Fourier analysis, and the particles on the transparent boundary were forced to move at the velocity of the analytical solution for Stokes waves in order to absorb the incident waves. The analysis was restricted to periodic waves. Wave propagation was simulated for two wave periods using the developed transparent boundary condition. The results showed that this transparent boundary transmitted the incident waves with small reflection and the simulation cost was lower than that for wave damping by a conventional highly viscous region.     

Wave reflection from partially perforated-wall caisson breakwater

In 1995, Suh and Park developed a numerical model that computes the reflection of regular waves from a fully perforated-wall caisson breakwater. This paper describes how to apply this model to a partially perforated-wall caisson and irregular waves. To examine the performance of the model, existing experimental data are used for regular waves, while a laboratory experiment is conducted in this study for irregular waves. The numerical model based on a linear wave theory tends to over-predict the reflection coefficient of regular waves as the wave nonlinearity increases, but such an over-prediction is not observed in the case of irregular waves. For both regular and irregular waves, the numerical model slightly over- and under-predicts the reflection coefficients at larger and smaller values, respectively, because the model neglects the evanescent waves near the breakwater.     

三维极限波的产生方法及特性

极限破碎波浪是造成海洋结构物破坏的主要因素之一,对极限波浪的产生方法和特性进行研究具有重要的工程意义.利用长波传播快、短波传播慢的原理,从理论上给出了产生三维极限波的方法,利用基于Boussinesq方程的数值模拟对该方法进行了验证,同时研究了中心频率、频率宽度和频谱形式等对极限波浪特性的影响,为该方法的进一步应用提出了建议.     

基于多源遥感数据的日本海内波特征研究

日本海特殊的地理位置和复杂的地形使得该海域内波表征极为复杂,遥感是大范围观测内波的有效手段,已被广泛应用于内波的探测研究。本文利用MODIS、GF-1和ENVISAT ASAR遥感影像,开展了日本海内波特征研究。通过提取内波波峰线,生成了日本海内波空间分布图;获取了内波的波峰线长度和传播速度,并基于非线性薛定谔方程反演了内波振幅。研究结果表明,日本海内波分布范围宽广,不仅大陆架沿海区内波分布密集,深海盆地也探测到了大量内波;日本海北部45°N附近海域有少量内波出现,利用高分影像探测到朝鲜陆架浅海区有大量小尺度内波,大和海盆、大和隆起的西南部海域没有发现内波。日本海内波波峰线长达100多千米,深海区的传播速度大于1 m/s;浅海区内波振幅约10 m左右,深海区可达60 m以上。     

Statistical characteristics of individual waves in laboratory wind waves I. Individual wave spectra and similarity structure

Statistical characteristics of individual waves in laboratory wind waves have been studied by use of a wind-wave tunnel. The individual waves are defined by actual undulations of the water surface at any instant, and are characterized by concentrated shearing stress and strong vorticity at their crests. A conspicuous self-similarity structure is found in the individual wave field. The similarity manifests itself as a simple spectral form, and as the statistical 3/2-power law between nondimensional wave height and wave period, and further as the -1/2-power relationship between nondimensional phase speed and frequency, for waves of the high frequency side. The normalized energy spectrum, specially defined for individual waves, has a form practically equivalent to the traditional spectrum for component waves in the main frequency range from 0.7 to 1.5 in the frequency normalized by the peak frequency, but does not have secondary peaks at harmonics. The phase speed of individual waves also coincides with that of component waves in the main frequency range.     

Characteristics of abnormal waves in North Sea storm sea states

A data set of storm wave records from the North Sea is analysed. Using current definitions of abnormal waves, eight of the largest wind waves are defined as abnormal waves. Twenty-four of the largest waves in time series, with a height larger than 10 m and with big vertical asymmetry are chosen for further analysis. Their individual characteristics are investigated and related to the global sea state characteristics. A comparison between measured data, second-order theory predictions and offshore basin data is made. The results for the chosen waves do not coincide with predictions of second-order theory. Considering that wind wave is second- and third-order non-linear, a new relationship between skewness and kurtosis is proposed for the sea states in which extremely asymmetric large waves have occurred. Another relationship between kurtosis and abnormality index of maximum waves is proposed too.     

Laboratory study of wave and turbulence characteristics in narrow-band irregular breaking waves

Wave elevations and water particle velocities were measured in a laboratory surf zone created by the breaking of a narrow-band irregular wave train on a 1/35 plane slope. The incident waves form wave groups that are strongly modulated. It is found that the waves that break close to the shoreline generally have larger wave-height-to-water-depth ratios before breaking than the waves that break farther offshore. After breaking, the wave-height-to-water-depth ratio for the individual waves approaches a constant value in the inner surf zone, while the standard deviation of the wave period increases as the still water depth decreases. In the outer surf zone, the distribution of the period-averaged turbulent kinetic energy is closely correlated to the initial wave heights, and has a wider variation for narrow-band waves than for broad-band waves. In the inner surf zone, the distribution of the period-averaged turbulent kinetic energy is similar for narrow-band waves and broad-band waves. It is found that the wave elevation and turbulent kinetic energy time histories for the individual waves in a wave group are qualitatively similar to those found in a spilling regular wave. The time-averaged transport of turbulent kinetic energy by the ensemble-averaged velocity and turbulence velocity under the irregular breaking waves are also consistent with the measurements obtained in regular breaking waves. The experimental results indicate that the shape of the incident wave spectrum has a significant effect on the temporal and spatial variability of wave breaking and the distribution of turbulent kinetic energy in the outer surf zone. In the inner surf zone, however, the distribution of turbulent kinetic energy is relatively insensitive to the shape of the incident wave spectrum, and the important parameters are the significant wave height and period of the incident waves, and the beach slope.