流动注射法测定海水中的无机氮和磷酸盐

使用流动注射分析技术测定海水中的无机氮和磷酸盐.氨氮、硝酸盐、亚硝酸盐和磷酸盐四项指标的检出限分别为:0.7μg/L、2.0 μg/L、2.0μg/L、0.28μg/L.测定实际海水样品加标回收率均在90％以上,相对标准偏差在20％以内,符合《海洋监测规范》[1]中的测定要求.该方法与传统的分光光度法相比减少了人为操作带来的实验误差和环境污染,具有快速、方便、基体干扰小,精密度和准确度高等优点,适合批量样品的测定.     

原子荧光形态分析仪在汞、锑形态分析中的应用

原子荧光形态分析仪SA-10是基于高效液相色谱和氢化物发生原子荧光联用技术的一台元素形态检测仪,该仪器对汞和锑形态的分析性能是：Hg（Ⅱ）、MetHg、EtHg、Sb（Ⅲ）和Sb（Ⅴ）的检出限分别为0．5．0．3,0．4、1和5μg／L,线性范围分别是0．5～1000、0．3～1000、0．4～1000、1～1000和5～1000μg／L,该区间内的线性相关系数均大于0．9990,标准偏差均小于3．0％。本文主要介绍了该仪器在海产品、环境水样、土壤中的汞形态分析和化妆品中的锑形态的应用。     

原子荧光法与直读测汞仪法测定汞的比较分析

汞根据形态不同常见的检测方法有：原子荧光法（AtomicFluorescenceSpectrometry,AFS）、原子吸收法（AtomicAbsorptionSpectrometry,AAS）、电感耦合等离子质谱法（InductivelyCoupledPlasmMassSpectrometry,ICP—MS）、气相色谱法（GasChromatography,GC）、直读测汞仪法（DirectMercuryAnalyzer,DMA）等。我国汞元素的检测标准,依然延续着传统的原子荧光法。采用原子荧光法检测固体样品时,无一例外均需要消化处理。在消化过程会遣成汞的大量损失,从而降低实验的准确性,同时汞的“记忆效应”仍然难以解决。本文通过对汞元素的检测方法的研究,得出原子荧光法和直读测汞仪法（DMA）两种方法均能达到满意的检测结果,但直读测汞仪法对总汞含量的分析,所用试剂用量少、线性好、检测周期短、方法检出限低、重复性好、准确度高、回收率好,并且样品无需消化处理,更适合总汞含量的测定。     

连续流动分析仪测定海水中氨氮的适用性研究

本文采用SKALAR SAN＋＋连续流动分析仪测定海水中氨氮,通过数理统计的方法验证其与国家现行标准方法的数据差异性,并考察了载流液和清洗频次对检测结果的影响,总结了该技术目前存在的不足。结果表明：连续流动分析法有良好的重现性、精密度和准确度,方法检出限为0.006mg/L,与国家标准方法测得结果无显著性差异,且能减少环境和人为因素误差。连续流动分析仪是一种全自动的分析仪器,对海水样品氨氮的分析能满足海洋环境监测的质量技术要求。     

离子色谱-电感耦合等离子体质谱联用法测定海水中碘的形态

本文建立了离子色谱与电感耦合等离子体质谱联用对海水中碘的两种形态——碘酸根和碘离子进行同时检测的方法,以大比例稀释和大体积进样方式消除基体干扰。实验表明,以IonPac AS14分析柱,50mmol／L（NH4）4CO3（氨水调至pH10．0）为淋洗液,1mL／min流速,1mL的进样量,海水样品稀释200倍,IO3^-和I^-的方法检测限分别为2．60ug／L和4．60ug／L。回收率为101．9％和105．1％,相对标准偏差（n=7）为1．8％和2．6％。     

五参数全自动营养盐分析仪的研制与应用

本文研制了一种用来检测海水中营养盐含量的五参数全自劝分析仪.应用该仪器对海水中的正确酸盐、氨氮、可溶性硅酸盐、硝酸盐和亚硝酸盐含量进行了测定.其中正磷酸盐的线性范围,检出限和相对标准偏差分别为10-400 μg/L(r0.9997),0.7 μg/L和0.4%;可溶性硅酸盐的线性范围,检出限和相对标准偏差分别为50-2...     

新型耐海水腐蚀不锈钢的研究

介绍了一种耐海水腐蚀不锈钢,通过对试验钢进行化学成分设计和熔炼,对其在热处理工艺、室内点蚀浸泡、力学性能、金相组织等方面做了测试,并与316L不锈钢进行比较,指出了该钢的特点,结果表明该试验钢具有良好性能。     

Corrosive Wear Performance of Monel K500 Alloy in Artificial Seawater

In corrosive wear, one of the most interesting phenomena is the synergism where both corrosion and wear are significantly increased, leading to much greater material losses than produced by the sum of material losses by either process alone. A systematic investigation was carried out in the present work to assess the electrochemical and corrosive wear behaviors of Monel K500 alloy sliding against alumina in artificial seawater using a pin-on-ring tribometer integrated with a potentiostat for electrochemical control. The open circuit potential clearly shifted to the cathodic direction due to sliding action. The corrosion current density was much higher under sliding than under corrosion only. Moreover, high normal load and rotation speed result in low open circuit potential and high corrosion current density. The material loss was greater under open circuit potential than under cathodic protection. Corrosion induced an increase in material loss. The material loss caused by a synergistic effect between corrosion and wear contributed to about 20% of the total material loss. The synergistic effect can be divided into wear-induced corrosion and corrosion-induced wear. Wear-induced corrosion was caused by damage to the passive film due to the sliding action of the counterbody, leading to accelerated dissolution. Corrosion can promote the growth and propagation of microcracks in the wear track, which causes corrosion-induced wear.     

汞分析仪及其应用

介绍了美国ＴＳＰ公司汞分析仪的工作原理，仪器组成和特点及其应用情况。     

Accurate Calibration of Mercury Vapour Indicators for Occupational Exposure Measurements using a Dynamic Mercury Vapour Generator

Abstract

An accurate and rapid calibration procedure for mercury vapour indicators used for occupational exposure measurements is described, using a dynamic mercury vapour generator traceable to the standard bell-jar calibration apparatus. The method provides greater flexibility, accuracy, and trace ability than the usual methods for the calibration of mercury vapour indicators used for occupational exposure measurements. The calibration procedure allows a correction to be applied to the mass concentration value displayed by the mercury vapour indicator. Measurement results from the mercury vapour indicator at the occupational exposure limit of 25 µg ·m^?3, following calibration, have been estimated to have an expanded uncertainty of 8%.     

乳粉中汞含量测定的不确定度评定

测量不确定度定义为表征合理地赋予被测量之值的分散性[1]。在ISO/IEC17025-1999中要求检测实验室具有评价不确定度的程序,能够对测量项目的不确定度做出正确的评估,满足客户及监测工作的要求。在这种情况下,实验室应努力找出不确定的所有分量且做出合理评定,确保检验结果不确定度已知度符合要求。作者依据测量不确定度的评定原则,通过实例,简要地阐述了原子荧光法测定乳粉中汞的不确定度评定方法,对检测领域测量不确定度的评定具有借鉴意义。     

Determination of Ammonia in Seawater by Multichannel Flow Injection Analysis

An analytical method that uses multichannel flow injection is reported to determine ammonia in seawater. The sample throughput was twenty-eight samples per hour. The linear dynamic range for ammonia was from 20.0–1000.0 μg N · L^?1 with a limit of detection of 0.27 μg N · L^?1, and recovery values between 98.1% and 104.6%. The relative standard deviation values for nitrogen as ammonia were 2.15–3.33% (n = 6). Statistical t-test analysis indicated that analysis by the flow injection method provided results that were statistically the same as standard procedures. The reported method was suitable for the determination of ammonia in seawater.     

燃煤时汞的排放及治理

燃煤是汞向环境中释放的主要污染源。重金属汞具有很强的生理毒性,燃煤产生的汞污染尚未引起足够的重视。文章针对煤炭在燃烧中存在着汞排放的实际情况,从汞在煤炭燃烧过程中的产生方式、形态转化、汞化合物的理化性质、排放方式以及全球汞污染物的排放状况和治理方式等多方面进行了详细阐述,这对于加强对汞污染物的监测和指导验收评价具有积极的作用。     

双阳极电化学氢化物发生原子荧光光谱法测定海水中的砷

用双阳极电化学氢化物发生原子荧光光谱法测定海水中的砷,不必通过化学氢化物发生,减少了化学试剂使用给环境带来的污染。对各种实验参数和干扰情况进行了详细研究。在选定的实验条件下,500μL进样量的As(Ⅲ)线性范围为5～20μg/L,检出限为0.36μg/L(信噪比S/N=3),20μg/L的As(Ⅲ)标准溶液平行进样13次,荧光信号(面积)的相对标准偏差(RSD)为2.22%,海水样品的加标回收率为95.7%～108%。本法灵敏度高、重现性好、结果准确可靠,可用于海水中砷的分析测定。     

水液压数字阀的电磁场数值研究

介绍了一种由2个二位三通换向球阀集成于一体的数字开关阀。该阀的阀体部分可作为电磁铁轭铁,衔铁部分可作为放大杠杆,从而使阀体和杠杆成为磁路的一部分。电磁线圈密封于阀体内,有良好的耐压性。因此,该阀适用于在海洋环境水下作业的液压系统。文中重点研究了位于电磁铁铁芯头部与衔铁接触处,能够咬合的特殊锯齿结构。在不同结构和几何尺寸下,利用有限元分析软件ANSYS对于电磁铁铁芯和衔铁部分进行了电磁场数值分析,得出电磁吸力特性曲线。仿真结果表明,这种具有特殊锯齿结构的电磁铁,在咬合前期具有较大的吸合力,咬合后期吸合力逐渐减小,因此能减小撞击且具有较高的响应频率。     

Synergetic Effect of Lubricant Additive and Reinforcement Additive on the Tribological Behaviors of PEEK-Based Composites under Seawater Lubrication

Polyetheretherketone (PEEK)-based composites reinforced with lubricant additive (polytetrafluoroethylene, PTFE) and reinforcement additives including carbon fiber (CF), glass fiber (GF), and bronze powder were prepared using a hot-press molding technique. The synergetic effects of different additives on the tribological behaviors of PEEK-based composites sliding against 316 steel under seawater lubrication were investigated systematically using a ring-on-block test rig. The results showed that lubricant additive PTFE can decrease the friction coefficient and consequently improved the wear resistance of PEEK under seawater lubrication, especially when the volume fraction of PTFE was about 20%. It was also found that the incorporation of CF can further improve the wear resistance of PEEK blended with 20% PTFE, especially under high load and high sliding speed. This suggested that a synergistic effect on improving the wear resistance of PEEK existed between PTFE and CF, which originated from good lubrication of PTFE, good reinforcement of CF, and good interfacial combination between CF and PEEK-20%PTFE. However, two other reinforcement additives of GF and bronze powder had an antagonistic effect but not a synergetic effect with PTFE; that is, the incorporation of the two additives greatly deteriorated the wear resistance of PEEK blended with 20% PTFE.     

混凝沉淀一体化设备在海水预处理中的试验分析

通过对海水预处理的试验和分析总结，我们认为采用混凝沉淀一体化设备去除水中的悬浮物和浊度是完全可行的。     

热法海水淡化技术简析

介绍了全球水资源的状况及我国淡水资源紧缺的现状,提出了海水淡化技术发展的必要性和其良好而广泛的市场前景,进而对主流热法海水淡化技术作了扼要的介绍、分析和比较,并展望其发展趋势。     

Architecture of Multilayer Cr/CrN Coatings for Wear Protection in Seawater: Cr/CrN Ratio and Total Thickness

Cr/CrN multilayer coatings with various Cr/CrN thickness ratios and total thicknesses were deposited on 316L stainless steel by multi-arc ion plating. The coatings were systematically characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and nanoindentation. Tribological behaviors were investigated using a ball-on-disk tribometer in artificial seawater. The results showed that the multilayer coating phases changed from Cr₂N + CrN to Cr + Cr₂N + CrN phases with an increase in Cr/CrN thickness ratio. The adhesion showed a slight difference for the coatings with different thickness ratios but significantly increased with total thickness. The hardness was also slightly improved by thickening the coatings. The friction coefficient and wear rate were lowest at a thickness ratio of about 0.3. However, there was no large difference in the friction coefficient between coatings with different thicknesses. The wear rate was lower for the thicker coatings under various loads. The load-bearing capacity was also improved by thickening the coatings.     

Determining and comparing the levels of heavy metal concentrations in two selected urban river water

This paper discussed the heavy metal pollution levels and the clean-up activities to improve the Gombak and Penchala River water quality in Kuala Lumpur. The Gombak River is a tributary of the Klang River passing through Kuala Lumpur. The Penchala River passes through the city of Petaling Jaya. Metal concentration levels as reported by the Department of Environment of Malaysia were used to assess the state of metal contamination of the rivers. The effectiveness of government efforts through engineering and river works and public awareness campaigns to strive for a healthier Gombak River and Penchala River was observed over a period from 1997 to 2009. Results showed that the concentrations of metals in the Gombak River were generally slightly better than those of the Penchala River. The Penchala River showed a better rate of quality improvement than the Gombak River but the absolute concentration values were generally higher.