亚硝酸盐现场自动分析仪化学分析工艺流程的优化研究

通过对亚硝酸盐分析工艺的优化研究,为亚硝酸盐现场自动分析仪的设计提供了可靠的依据;简化了分析工艺,便于实现仪器的自动化;有利于仪器的小型化。哑硝酸盐分析工艺的优化技术,还可以推广到其它化学要素的现场自动分析仪的研制过程中。     

Wave loads on large vertical cylinders: A design method

The finite element method based on linear diffraction theory proposed by Zienkiewicz and Bettess (1977) has been used to compute wave loads and moments about the bed of surface piercing cylinders of circular, square, rectangular and elliptical sections for different angles of wave incidence. On the basis of the results obtained, a design method is presented in the form of simple design charts for estimating wave forces and moments on large cylinders of arbitrary sections. The numerical solutions obtained have been checked for their validity by comparing with other theoretical solutions and experimental data. Further the application of the design method to a case study shows good correlation with experimental and other theoretical solutions.     

Active fin control for yacht using virtual instrumentation

Virtual instrumentation represents a PC based control system which incorporates manipulation of data acquired from physical transducers in specific ways using a very high level graphical environment. The deployment of this non-traditional approach is demonstrated in this paper by application to design of a fin control system for a yacht. One of the disadvantages of the traditional stabilizer system is the enormous hardware involved in the controllers and instrumentation panels, which make maintenance and troubleshooting difficult. With the help of virtual instrumentation, design of the stabilization controller and instrumentation panels can be carried out much more effectively, in comparison with the traditional hardware approach. A multi-disciplinary approach is adopted here and it consists of the assessment of the hydrodynamic coefficients of the yacht using a numerical package, representation of the hydrodynamic coefficients by suitable polynomial functions, identification of the time dependent fundamental frequency in the roll disturbance signal sample, generation of control signal for an appropriate fin angle based on the fin lift characteristics of the chosen fin and employment of feedback control to maintain the fin at the appropriate angle for maximum control. Once the ship based hydrodynamic coefficients are generated, the entire control algorithm is developed in the virtual instrumentation mode using LabVIEW environment. The effectiveness of the system is verified through laboratory tests on a yacht hull form. The control algorithm permits choice of frequency dependent hydrodynamic coefficients by use of a harmonic distortion analyzer in the virtual instrumentation environment.     

Analysis of testing methods of pipelines for limit state design

It is well known that the design of submarine pipelines relies on accurate test results for the local buckling collapse of pipes subjected to bending loading. The present paper analyses apparently anomalous values of axial tensile and compressive strains from recent test results in comparison to the values that would be expected on the basis of simple bending theory. This could have important consequences for the efficacy of the design factors derived using these results. The cause of the differences between the strain values obtained in the tests and those expected on the basis of simple bending theory are explained using finite element modelling. The differences result from the type of collars and supports commonly used in bending tests, the effects of which persist for a greater length along the test pipe than has hitherto been assumed. In general, it is pointed out that the application of the simplified engineering theory of bending can be erroneous when ovalisation is imposed or, on the contrary, the boundary conditions of the section are restrained from ovalising deformations. The influence of the D/t ratio is also analysed.The results contribute to the understanding of a crucial limit state for the design of onshore and offshore pipelines.     

应用于海洋站温盐传感器的缓冲止旋方法

为解决温盐传感器在海洋站应用中存在的电缆缠绕和壳体磨损等问题,保障传感器的长期业务化运行,文章提出改进温盐传感器安装方式的缓冲止旋方法。研究结果表明：在实验室环境下,通过以螺旋电缆代替直线电缆和设计缓冲浮子装置二者结合的温盐传感器安装方式,可有效减少电缆缠绕、避免传感器磕碰磨损和减小海流影响,同时安装简单、便于维护和具有广泛应用性。该方法仍须在海洋站实际应用中进一步验证和完善。     

Lateral Bearing Capacity of Multi-Bucket Foundation in Soft Ground

The bucket foundation is a new type of foundation for offshore application to intermediate-depth waters. It has advantages over conventional ones. However, there is no consensus in the analysis and design of this type of foundation. In this paper, the lateral bearing capacity and the failure mechanism of multi-bucket foundations are studied with different connection stiffness and bucket spacing by use of a three-dimensional finite element method. Based on the numerical analysis results, a limit analysis method of plasticity for evaluating the lateral bearing capacity of large-spacing multi-bucket foundation with rigid connection in soft ground is proposed. This method provides a simple procedure that gives results comparable to those from the finite element analyses.     

An interconnect width and spacing optimization model considering scattering effect

As the feature size of the CMOS integrated circuit continues to shrink, the more and more serious scattering effect has a serious impact on interconnection performance, such as delay and bandwidth. Based on the impact of the scattering effect on latency and bandwidth, this paper first presents the quality-factor model which optimises latency and bandwidth effectively with the consideration of the scattering effect. Then we obtain the analytical model of line width and spacing with application of curve-fitting method. The proposed model has been verified and compared based on the nano-scale CMOS technology. This optimisation model algorithm is simple and can be applied to the interconnection system optimal design of nano-scale integrated circuits.     

福建洛阳江河口湿地沉积物粒度特征及其沉积环境意义

沉积物粒度是反映湿地沉积环境的重要指标之一．利用Mastersizer2000型激光粒度仪对取自福建洛阳江河口不同类型湿地的6根短柱状沉积物样品进行了粒度分析．结果显示,该地区沉积物基本为粘土质粉砂,红树林湿地内的沉积物最细,分选程度最好;互花米草湿地圈闭了大量水流带来的粗、细颗粒物质,导致平均粒径相对较大,分选相对较差．粒度参数的相关分析结果显示,平均粒径与分选系数的显著正线性相关,揭示了该地区水动力作用弱、物质来源单一的沉积环境,显著增加了河口湿地沉积速率．     

Automatic colorimetric analyzer prototype for high frequency measurement of nutrients in seawater

This paper describes the characteristics of a prototype of a modular multiparametric analyzer (MicroMAC FAST MP3) for automatic monitoring of seawater and analytical methods for nutrients.The MicroMAC FAST reactor is an evolution of the basic LFA (Loop Flow Analysis) reactor. It has been conceived to assay ammonium, nitrate–nitrite and orthophosphate at low concentration in seawater samples. A sample analysis is 3–4 times faster than that obtainable with a standard LFA reactor. With respect to the previous analyzer a temperature control (30–52 °C) on the measurement cell has been added (only for modules NH₄ and PO₄), while the colorimeter and the related links for transporting the sample have been moved beyond the Loop and form a hydraulic-optical set almost completely independent from the main LFA. All the steps of a wet-chemical colorimetric analysis method are carried out in an analysis cycle sequentially. The hermetic closed Loop provides full protection against background interference, which is a basic requirement for stable trace analysis. At the start of a cycle the loop is washed and filled with sample. The sample color is measured for compensation. Small amounts of concentrated reagents are added and mixed with high intensity. This new technique allows the preparation of two products of reaction which can be introduced at intervals of 150 s in the measurement cell. The intensity of the color of the reaction product is measured on the colorimeter using a monochromatic light beam of specific wavelength. The statistical test shows that the results of automated and manual analyses agree for all the examined parameters. Precision of all three analyses is ≤ 4% RSD.Multiparametric online analyzer: it is possible to connect the analytical modules to a data logger with analogue and digital signals, in order to have online simultaneous analysis of the sample. A typical application is used during research at sea which vessel does not require an operator.     

臭氧法海水化学需氧量测量仪

海水化学需氧量(COD)是海水中有机污染物的综合指标,是海洋环境监测最重要的项目之一,目前我国海洋环境污染日趋严重,现有的COD测量方法远远不能满足形势的需要,研制开发现场、快速、自动、连续运行的“COD测量仪”势在必行,也是海水COD分析技术发展方向和发展趋势。在国家863计划的支持下,我们研制成功了可用于现场的“臭氧法海水化学需氧量测量仪”。文中介绍了臭氧法海水化学需氧量测量仪的原理、实验室现场试验结果和海试现场情况。大量实验数据表明,该测量仪具有测量快速、结果准确、长时间不需维护等特点。     

Modeling of pumping cold deep nutrient-rich seawater for mariculture and nuclear power plant cooling applications

A simple theoretical model is developed to assess the technical feasibility of pumping cold deep nutrient-rich seawater for mariculture and nuclear power plant cooling. Simulations for two locations in eastern Taiwan have shown that replacing warm surface seawater by cold deep seawater as nuclear power plant coolant is technically feasible for pipes with diameters larger than 150 cm and intake levels deeper than 400 m. The gravitational force-induced flow system is also examined and shown not to be suitable for the nuclear power plant cooling application. However, it is shown than both systems are suitable for mariculture applications. The required pumping powers at different pipeline conditions are also presented in the paper, for design purposes.     

Some methods to obtain the added resistance of a ship advancing in waves

Added resistance in waves is an important part of ship dynamic due to its economical effect on ship exploitation. Can the ship sustain speed in a rough sea state? If not, this will produce delays and economical losses if added resistance is not taken into account in the propulsion design. There are not many simple methods to obtain the added resistance in waves of a ship, and the validity of the results is not always good enough for different ships. In this paper, some theories that can be used to predict the added resistance of a ship are studied and validated against seakeeping tests of some monohull models. Tests and results focus in head seas, which are the most severe for the added resistance. Experimental results are compared with numerical calculations and conclusions about the range of application of the presented theories are obtained.     

PC-104 模块在水下原位化学分析仪器中的应用

使用PC-104 嵌入式平台作为控制模块开发了流动注射分析仪的控制和采集系统, 实现了载流驱动、进样控制及CCD(charge coupled device)光谱数据采集等复杂功能。结果表明: PC-104 模块在复杂控制和海量数据采集方面具有很好的实用性, 能大大缩短开发周期, 为结构复杂的水下原位化学分析仪的开发提供良好的控制采集平台。     

浮游植物初级生产力自动测量仪及其测量不确定度研究

简要介绍了最新研制的浮游植物初级生产力自动测量仪的工作原理和系统组成,并对其测量不确定度进行了探讨。     

PC-104模块在水下原位化学分析仪器中的应用

使用PC-104嵌入式平台作为控制模块开发了流动注射分析仪的控制和采集系统,实现了载流驱动、进样控制及CCD（charge coupled device）光谱数据采集等复杂功能。结果表明：PC-104模块在复杂控制和海量数据采集方面具有很好的实用性,能大大缩短开发周期,为结构复杂的水下原位化学分析仪的开发提供良好的控制...     

渤海油田示范区地理信息系统(GIS)的规划设计

在进行了充分需求分析基础上,对渤海油田示范区地理信息系统的数据库和应用系统进行了详细设计,数据库的设计主要是本着对象模型和关系模型相结合的原则进行的,而应用系统的设计主要考虑了以下原则,即先进性和实用性、开放性和标准性、可扩展性和可维护性、安全性和保密性、可靠性和稳定性以及具有良好的二次开发能力等。对于系统的体系结构设计,主要从系统的层次结构、硬件体系结构和软件体系结构等方面作了详细的规划设计。     

碱性高锰酸钾法海水化学耗氧量(COD)在线测量仪的研制

一种新型的海水COD在线测量仪已经研制出来,其采用了碱性高锰酸钾法和流动注射分析技术,仪器的测量结果与标准方法有很好的一致性,它们的相关系数超过0.98。     

A method to calculate design tide levels on the basis of numerical model of tidal current and its application

In order to determine the design tide levels in the areas without measured tide level data, especially in the areas where it is difficult to measure tidal levels, a calculation method based on a numerical model of tidal current is proposed. The essentials of the method are described, and its application is illustrated with an example. The results of the application show that the design tide levels calculated by the method are close to those determined by long-time measured tide level data, and its calculation precision is high, so it is feasible to use the method to determine the design tide levels in the areas.     

循环荷载作用下合成纤维系缆粘弹塑性应力应变关系

在循环载荷作用下,合成纤维系缆的应力应变关系表现出明显的非线性特性,直接影响系泊缆绳的动力响应。如何针对其在循环载荷作用下的应力应变关系进行准确的定量描述是有关绷紧式系泊系统设计的关键问题。国内外研究者之前的研究不能反映缆绳的载荷历史、蠕变特性以及刚度变化过程,因此提出一个粘弹性粘塑性模型来描述合成纤维系缆的应力应变关系。本模型能够反映合成纤维缆绳的时间变化特性以及在整个加载—卸载过程中的刚度变化。此外,提出了明确的参数确定方法及步骤,基于简单的蠕变实验可以确定模型的各个参数。将两种载荷条件下聚酯缆绳的实验结果与模型结果进行对比,二者吻合较好,证明了模型的有效性和可靠性。本研究对于绷紧式系泊系统的研发和工程应用具有重要意义。     

用RAM扩充程序存贮器

给出一种用ＲＡＭ扩充程序存贮器的方法，以及具体的硬件线路。这种简便实用的方法可为用户提供一种根据需要自行修改或编写应用程序的环境．