Organotin antifouling paints and their alternatives

Tributyltin and triphenyltin compounds have excellent biocidal properties and almost all vessels in the world have used these paints since early in the 1960s. Contrary to expectation, as shown by experimental data at the beginning of organotin chemistry, triorganotins are exceptionally stable in the sediment or in dark places in the deep sea. Since triorganotins do not decompose rapidly in seawater, many incidences of deformities in some shellfish have been linked to their presence, even when present at extremely low concentrations. Alternative tin‐free antifoulants containing other biocides, such as copper compounds and organic compounds, have been developed and used since the late 1980s. Some nations have already banned the use of organotin antifouling compounds for small vessels, and in 2001 the International Maritime Organization decided to ban completely the use of the organotin compounds from the year 2003. Therefore, it is necessary to find economically and environmentally better biocidal substances as soon as possible. Moreover, the development of antifoulants containing environmentally safe natural products, fouling release coatings, electroconductive coatings, etc. have long been anticipated from the new point of conservation of the world marine environment. Copyright © 2003 John Wiley & Sons, Ltd.     

Windows CE.NET的串口解析

简要介绍了Windows CE.NET下设备管理器的管理机制,分析了串行设备的命名规则,并在此基础上深入分析、探讨了x86体系下Windows CE.NET串口注册表的设置方式以串口地址的分配方式,最后给出了一种向平台添加一个额外串口的方法,还给出了重获地址为0x03F8的串行端口的具体操作步骤.     

城市建设和城市的持续发展

分析了由城市建设所引起的城市持续发展所面临的问题，并就相应的对策与建议作了初步的探讨。     

On a property related to convergence in probability and some applications to branching processes

It is shown that any real-valued sequence of random variables {X_n} converging in probability to a non-degenerate, not necessarily a.s. finite limit X possesses the following property: for any c with P(X? (c ? δ, c + δ)) > 0 for all δ > 0, there exists a sequence {c_n} with lim_n→∞ c_n = c such that for any ε > 0, lim_n→∞ P(Xδ (c ? ε, c + ε) |X_n = c_n) = 1. This property is applied to various types of branching processes where $\text{X}{}_{\mathrm{n}}\text{=}\text{Z}{}_{\mathrm{n}}\text{C}{}_{\mathrm{n}}$ or $\text{X}{}_{\mathrm{n}}\text{=}\text{U(Z}{}_{\mathrm{n}}\text{)}\text{C}{}_{\mathrm{n}}\text{{C}{}_{\mathrm{n}}\text{}}$ being a sequence of constants or random variables and U a slowly varying function. If {Z_n} is a supercritical branching process in varying or random environment, X is shown to have a continuous and strictly increasing distribution function on (0, ∞). Characterizations of the tail of the liniting distribution of the finite mean and the infinite mean supercritical Galton-Watson processes are also obtained.     

Improvements of Speciation Analyses in Environmental Matrices

The release of some organometallic compounds and other chemical forms of elements in the environment has led to great international concern because of their high toxicity. The validation of the analytical techniques became of paramount importance which led the Community Bureau of Reference (BCR) to decide on the organisation of a series of projects for the improvement of the quality of speciation analyses. In addition, it was found useful to discuss thoroughly the different sources of error likely occurring in speciation analyses and a workshop was organized for this purpose; the aim of this workshop was to discuss the state of the art of speciation determinations, to define use, applicability and necessity of determinations of element species, to investigate where limitations exist and discuss the work necessary to overcome these and to detect where techniques have sufficiently been developed to produce reliable and valuable results. This paper presents the organization of the workshop, its main issue and describe the state of the current BCR projects on speciation.Abbreviations AAS Atomic absorption spectrometry - CVAAS Cold vapour AAS - DPP Differential pulse polarography - ECD Electron capture detector - ETAAS Electrothermal AAS - FIA Flow injection analysis - FID Flame ionisation detector - FLUOR Spectrofluorimetry - FPD Flame photometric detector - GC Gas chromatography - HG Hydride generation - HPLC High performance liquid chromatography - HPLC-AES HPLC atomic emission spectrometry - INAA Instrumental neutron activation analysis - ICPAES Inductively coupled plasma AES - MS Mass spectrometry - QFAAS Quartz furnace AAS - RNAA Neutron activation analysis with radiochemical separation     

Asymptotically One-Dimensional Diffusion on the Sierpinski Gasket and Multi-Type Branching Processes with Varying Environment

Asymptotically one-dimensional diffusions on the Sierpinski gasket constitute a one parameter family of processes with significantly different behaviour to the Brownian motion. Due to homogenization effects they behave globally like the Brownian motion, yet locally they have a preferred direction of motion. We calculate the spectral dimension for these processes and obtain short time heat kernel estimates in the Euclidean metric. The results are derived using branching process techniques, and we give estimates for the left tail of the limiting distribution for a supercritical multi-type branching process with varying environment.     

A fibre optic connector suitable for use in a rugged environment

The advantages and disadvantages of employing the expanded beam technique for a fibre optic connector are discussed. The design of a connector, based on this principle and suitable for use in a rugged environment, is described. Results of various handling tests carried out on this connector are given.     

A Study on the Engineering Geological Properties of Fine-grained Marine Sediments

Through studies on the engineering geological properties of fine marine sediments, this article fully verified that the sedimentary environment is an important factor which determines the engineering geological properties of fine marine sediments. Meanwhile, these properties are controlled and affected by factors such as composition, physico-chemical nature, micro-textures, etc. of fine soils.     

Analytical chemistry of freshwater humic substances

Dissolved organic carbon (DOC) in aquatic environments represents one of the largest active organic carbon reservoirs in the biosphere. Current ideologies concerning the sources of DOC, how it is formed and utilized, and what determines the quality of DOC are examined. Humic substances can comprise a significant fraction of the DOC and developments in methods of analysis including the isolation and characterization of this fraction are reviewed.     

基于FCE的建设项目环境效益可研指标的应用——以高速公路建设项目为例

应用FCE进行建设项目环境效益可研指标体系综合评价是一条科学精简的途径.高速公路建设项目对项目沿线环境的影响典型而尖锐,以高速公路建设项目为例分析FCE在建设项目环境效益可研指标中的应用,并以福银高速公路一期工程尤溪段施工期环境效益可研为例建立应用模型.