陷落柱地震波超前探测数值模拟与应用

针对陷落柱与周围煤体之间存在明显波阻抗差异的特点,建立巷道内地震波超前探测陷落柱数值模型。采用波场正演模拟方法,分析巷道前方存在陷落柱时的地震波场特征,总结出基于绕射偏移的陷落柱边界探测方法。在新元矿南二正巷实际超前探测中,该方法准确圈定了巷道前方陷落柱的范围。探测结果和实际揭露情况对比表明：地震波超前探测技术可以对巷道前方120m范围内的陷落柱构造进行有效预测。     

简柱体新型快捷算法及应用简介

将各类简柱体（含拟柱体）的内插面积和体积计算通式表示为一个简单的二次三项式及其定积分形式,实现了一式多用和有关的直接复合运算,可使常规的复杂定积分近似计算转化为简单的精确计算。     

俄罗斯阿尔丹地块西部穆龙斯克杂岩体中的碱性交代岩

含紫硅碱钙石、镁钠钙闪石（钠透闪石－石棉）及蓝色软透闪石的碱性交代岩的形成首先是由硅酸和碱（Ｎａ２Ｏ和Ｋ２Ｏ的不同作用）的隋性及ＦｅＯ,ＭｇＯ,ＣａＯ和Ａｌ２Ｏ３的强烈活性决定的。含蓝色软透闪石和镁钠钙闪石（钠透闪石－石棉）的交代岩是岩浆期后溶解演化的中期产物,而含紫硅碱钙石的交代岩却是其晚期的产物。     

振冲碎石桩在大型贮气柜地基加固中的应用

介绍了采用碎石桩对大型贮气柜地基进行加固的工程实例,总结了工程设计与施工的成功经验。     

Numerical study on the reverse drift force of floating BBDB wave energy absorbers

The motions and time-mean horizontal drift forces of floating backward-bent duct buoy wave energy absorbers in regular waves are calculated taking account of the oscillating surface-pressure due to the pressure drop in the air chamber above the oscillating water column within the scope of the linear wave theory. The present numerical results show that the time-mean drift forces of backward-bent duct buoys are in the reverse direction of propagation of the incident waves over specific frequency ranges as found by McCormick through his experimental work. The drift force has been calculated by the near-field method. A brief discussion on Maruo’s formula which shows that the time-mean drift force must be in the direction of propagation of the incident waves, has also been presented.     

海水中硝酸盐铜镉柱还原测定操作步骤的优化研究

本文比较了硝酸盐测定的铜镉柱还原法在两个规范中技术指标和操作工艺的差异.针对本实验室具体条件,对该测定方法的某些步骤(如镉柱制备、蠕动泵、流速选择、加氯化铵缓冲液方法等)进行优化研究,选择适宜的改进方法,以便将硝酸盐铜镉柱还原测定方法结合进本实验室已有的营养盐测定系统中.     

Semi-Active TLCD Control of Fixed Offshore Platforms Using Artifical Neural Networks

1 .Introductionanyoffshoreplatformshavebeenbuiltwiththedevelopmentofoceanengineering .However ,mostoffshorearelocatedinseismicregionsandtheplatformsareeasilytobeseriouslydamagedbyearthquakes.Hence ,theanti earthquakedesignhasalwaysbeenamajorpartofresearchonoffshoreplatforms.Theinclusionofvibrationabsorbersintheoffshoreplatformcanbeanattractivemethodofmitigatingseismicresponses .Vibrationabsorberscanbecategorizedintoactiveandpassive .Thetunedmassdamper (TMD)(FujinoandAbe ,1 993) ,eitherpassi…     

Response mitigation on the offshore floating platform system with tuned liquid column damper

In this study a typical tension-leg type of floating platform incorporated with the tuned liquid column damper (TLCD) device is studied. The purpose is to find an effective and economic means to reduce the wave induced vibrations of the floating offshore platform system. The floating offshore platform has been widely applied for the offshore exploitation such as operation station, cross-strait bridges, floating breakwater and complex of the entertainment facilities. For offshore platform being employed as a public complex the stability and comfort to stay will be the major concern besides the safety requirement. Therefore, how to mitigate the vibration induced from waves and similar environmental loading becomes an important issue. The TLCD system utilizing the water sloshing power to reduce the vibration of the main structure, a newly developed device that could effectively reduce the vibrations for many kinds of structure is the first-time employed in the floating platform system. In both the analytical and experimental results it is found that the accurately tuned TLCD system could effectively reduce the dynamic response of the offshore platform system in terms of the vibration amplitude and the resonant frequency.     

Impact of the Mediterranean Outflow Water on particle dynamics in intermediate waters of the Northeast Atlantic, as revealed by Th and Th

Over the last decade ²³⁴Th has become increasingly used to study particle transport in the ocean on a timescale of weeks. The application of ²³⁴Th is mainly focused on the determination of particle and associated carbon fluxes from oceanic surface water. However, ²³⁴Th is also suitable for investigating particle dynamic from the upper ocean down to interface sediments, as illustrated by the present work which reports unexpected behavior of ²³⁴Th in intermediate waters associated with the Mediterranean Outflow Water (MOW). Concentration profiles of dissolved ²³⁸U and ²²⁸Ra, and dissolved and particulate ²³⁴Th and ²²⁸Th were measured in the Mediterranean Outflow Water (MOW) near the Gibraltar Straits and at two sites (36°30′N–15°35′W, Nicole; 36°27′N–10°35′W, Yseult) which had hydrographic characteristics of Meddies, i.e. MOW that propagates as eddies in the Northeastern Atlantic at intermediate depths.There are marked differences in the distribution of thorium between MOW and the surrounding Atlantic waters. At the youngest Meddy Nicole salinity maximum at 1000 m depth, ²³⁴Th(total) : ²³⁸U and ²²⁸Th(total) : ²²⁸Ra activity ratios are significantly lower than radioactive equilibrium, indicating an unusual deficit of short half-life thorium nuclides. This implies an export of thorium, presumably on particles, from intermediate Meddy Nicole waters. This process is supported by an increase of particulate thorium fluxes measured in sediment traps deployed for two weeks above and within Meddy Nicole. In contrast, offshore Meddy Yseult has more typical profiles of both thorium nuclides that are nearly in equilibrium with their parents. These results indicate that at intermediate depths, the presence of MOW affects the exchange of reactive elements between particles and dissolved forms and enhances the downward flux of particles from intermediate waters in the Northeast Atlantic.