ALEXANDRITE AND ITS POPULARITY AS A GEM-STONE IN NORTH CHINA

INTRODUCTION. The reason for having this short paper made public is not so much as to unfold the results of any scientific investigation on the subject matter, but rather as a direct outcome of the response to the repeated inquiries, set     

Stream Function Wave Derived by Unified Variational Principle of Water Gravity Wave

Based on the linear wave,solitary wave and fifth order stokes wave derived by use of the Uni-fied Variational Principle of Water Gravity Wave(UVPWGW),this paper derives stream function wavetheory by using UVPWGW.This paper will handle the Kinematic Free Surface Boundary Condition(KFSBC)and Dynamic Free Surface Boundary Condition(DFSBC)directly and give the optimum solu-tion,instead of the conditions ∑(Q_(av)-Q_i)~2=min,and the related equations of stational condition.When the wave height H,period T and water depth D are given,the original stream function wave willbe determined,and can not be adjusted if it does not agree with the real case;in the present method,the ad-justment can be done by adding several constraint conditions,for example,the wave profile can be ad-justed according to the condition of accurate peak position.The examples given in this paper show that forthe original stream function wave,the DFSBC can be fairly well satisfied,but the KFSBC can not;howev-er,the stream function wave derive     

34万吨级FPSO的中横剖面优化设计

以中横剖面的面积最小为目标函数，应用自适应步长随机搜索法，对34万吨级FPSO中横剖面进行了优化设计，并将规范设计结果和优化设计结果进行了比较，优化效果较好。     

Marine disaster prevention and integrated coastal zone management

1 MAJN CHARAcrERISTICS OF MARINE DISA5TEROwing to marine natural environment anomaly and imense changr, alI those disastersthat cause Peoples life and propedy loss over the sea aod coast area are called marinedisasters. China is a country with big sea area, of coast line l8000 km length, precinctsea area 3,000,000 km', more than 6500 islands bigger than 500 m2 with coast line of allislands 14000 km length. The Pacific Ocean is ocean with the most frequent marine disasters,further…     

A New Model for Ice Forces on A Conical Structure

The ice force is an important factor to be taken into account for offshore structures in cold regions, and the calculation method of the ice force is meaningful for the offshore structure design. The cone is now used as an optimal ice-resistant structure because it can cause bending failure of the ice sheet. The interaction between an ice sheet and a conical structure is studied in this paper and Croasdale‘s model is modified based on field observations. The newly built model separates the ice sheet into the emersed part and the floating part, and the equilibrium analyses are canied out respectively. The bending moment distribution of the ice sheet is analyzed for the determination of the position of bending failure, which serves as a supplementary restraint. The analytic solution of the ice foree on a conical structure is obtained it is verified with the experimental data of previous researches.     

Mg—Al水滑石纳米晶热分解行为的TG—MS研究

利用热重-质谱联用仪(TG-MS)和多晶XRD对水热法制备的Mg-Al水滑石纳米晶的热分解行为进行表征研究表明:Mg-Al水滑石的热性能与其晶体化学特征有密切的关系。Mg-Al水滑石的热分解过程可分为4个阶段:①T≤280℃时,失层间H2O;②T=280℃~380℃时,失层板中[Mg—OH—Al]结构单元OH-;③T=380℃~580℃时,失层板中[Mg—OH—Mg]结构单元的OH-;④T=395℃~580℃时,层间CO32-逸出。后两个阶段有较大重叠性。[Mg—OH—Mg]中OH-和CO32-最大逸出量对应的温度明显不一致。[Mg—OH—Mg]中OH-的逸出是导致层状结构破坏的诱因,热分解的阶段性随升温速率提高而表现得明显。Mg-Al水滑石的热分解行为受扩散控制。     

农产品样品无机元素分析测试技术探讨

对全国土壤污染状况调查农产品样品无机元素所选用的分析方法进行了探讨,提出了比较科学合理、先进快速、高效准确的元素监测分析方法,并对部分元素形态分析提出了相关建议。     

地质资料数字化的作用及推进数字化工作的途径

阐述了数字化是当前地质档案管理的发展趋势,提出了应加快实现档案数字化网络建设及地质资料管理数字化建设目标。     

应用地球化学方法评价断层的封闭性

断层的封闭性和连通性研究对于了解断层在油气成藏和石油开发中的影响具有重要的意义.根据断层附近油藏的地球化学特征, 可以研究排烃期断层的封闭性.在涠西南凹陷油田的研究工作中, 通过断层两端油层的化学组成指纹的差异, 证实了断层的存在, 虽然断距较小, 但仍影响了油藏的连通.对欧利坨子地区靠近断层的油藏分析表明, 本区的深大断裂可以作为油气的有效通道, 靠近断层油藏成熟度较高, 且含氮化合物较丰富.本研究提供的2个实例证实地球化学方法用于判断断层的封闭性有着不可替代的优越性.