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62321-2013-4中文翻译

62321-2013-4中文翻译
62321-2013-4中文翻译

DETERMINATION OF CERTAIN SUBSTANCES

IN ELECTROTECHNICAL PRODUCTS –

Part 4: Mercury in polymers, metals and electronics

by CV-AAS, CV-AFS, ICP-OES and ICP-MS

1 概述

This standard specifies the determination of the levels of mercury (Hg) contained in electrotechnical products. These materials are polymers, metals and electronics (e.g. printed wiring boards, cold cathode fluorescent lamps, mercury switches). Batteries containing Hg should be handled as described in [1] 1 . The interlaboratory study has only evaluated these test methods for plastics, other matrices were not covered.

这个标准规定了电子电气产品中Hg含量的测定。这些材料是聚合物,金属和电子产品(例如:印刷纸,冷阴极荧光灯,水银开关)。含有Hg的电池应该按【1】1中的描述处理。多个是实验室仅仅评估了对塑料的测试方法,并没有覆盖其他材料。

This standard refers to the sample as the object to be processed and measured. What the sample is or how to get to the sample is defined by the entity carrying out the tests. Further guidance on obtaining representative samples from finished electronic products to be tested for levels of regulated substances may be found in IEC 62321-2. It is noted that the selection and/or determination of the sample may affect the interpretation of the test results.

本标准指的是样品的处理和测试。样品或获得的样品被定义为测试的实体。在IEC 62321 – 2中可以找到,进一步从限制含量的电子产品成品上获得有代表性待测样品。值得注意的是选择和/或测定的样品可能会影响测试结果的解释。

This standard describes the use of four methods, namely CV-AAS (cold vapour atomic absorption spectrometry), CV-AFS (cold vapour atomic fluorescence spectrometry) ICP-OES (inductively coupled plasma optical emission spectrometry), and ICP-MS (inductively coupled plasma mass spectrometry) as well as several procedures for preparing the sample solution from which the most appropriate method of analysis can be selected by experts.

本标准描述了CV-AAS(冷蒸气原子吸收分光光谱法)、CV-AFS(冷蒸气原子荧光分光光谱法)、ICP-OES(电感耦合等离子体原子发射光谱法)和ICP-MS(电感耦合等离子体质谱法)等四个方法的使用及制备样品溶液的几个步骤,从中,专业人员可以选用最合适的分析方法。

Analysis by CV-AAS, CV-AFS, ICP-OES and ICP-MS allows the determination of the target element, mercury, with high precision (uncertainty in the low per cent range) and/or high sensitivity (down to the μg/kg level). The test procedures described in this standard are intended to provide the highest level of accuracy and precision for concentrations of mercury in the range from 4 mg/kg to 1 000 mg/kg. The procedures are not limited for higher concentrations.

以CV-AAS、CV-AFS、ICP-OES 及ICP-MS 分析测定目标元素,汞,具有高精确度(不确定度在低百分率范围内)及/或高灵敏度(达到μg/kg 级别)。本章所描述的测试程序旨在为汞浓度处于4 mg/kg 至1000 mg/kg 范围时提供高准确度和精密度。测试程序不受更高浓度限制。

For direct analysis, using thermal decomposition-gold amalgamation in conjunction with CV-AAS (TD(G)-AAS) can be also applied for mercury analysis without sample digestion,although the detection limits are higher than other methods due to the reduced sample size.

直接分析,可以使用thermal decomposition-gold amalgamation配合CV-AAS (TD(G)-AAS)用于未经消解的汞分析,但是检出限高于其他方法由于减少了样本大小。

注1 Figures in square brackets refer to the bibliography.方括号中的数字指可查阅参考书目。

2 引用标准

The following documents, in whole or in part, are normatively referenced in this ocument and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. 以下参考文件对于本文件的应用是密不可分的。对于注明日期的参考文件,所引用的版本适用于本标准。对于未注明日期的参考文件,所引用的参考文件的最新版本(所括修正案)适用于本标准。

IEC 62321-1, Determination of levels of certain substances in electrotechnical products –

Part 1: Introduction and overview

IEC 62321-2, Determination of levels of certain substances in electrotechnical products –

Part 2: Disassembly, disjointment and mechanical sample preparation 2

IEC 62321-3-1, Determination of certain substances in electrotechnical products – Part 3-1: Screening – Lead, mercury, cadmium, total chromium and total bromine by X-ray fluorescence Spectrometry

IEC 62554, Sample preparation for measurement of mercury level in fluorescent lamps

ISO 3696, Water for analytical laboratory use – Specification and test methods

注2 To be published. 出版

3 术语、定义和缩写

3.1 Terms and definitions 定义和术语

For the purposes of this document, the terms and definitions given in IEC 62321-1 as well as the following, apply.

IEC 62321-1以及以下术语和定义适用于本文件

3.1.1 accuracy精确度

closeness of agreement between a test result and an accepted reference value

测试结果和公认的参考值之间的一致程度

3.1.2 blank calibration solution校正空白溶液

calibration solution without analyte

校正溶液中没有被分析物

3.1.3 calibration standard校正标准物质

substance in solid or liquid form with known and stable concentration(s) of the analyte(s) of interest used to establish instrument response (calibration curve) with respect to analyte(s) concentration(s)

固体或液体形态的物质,它具有已知的、稳定浓度的目标分析物,根椐分析物的浓度来建立仪

器的响应(标准曲线)

3.1.4 calibration solution校正溶液

solution used to calibrate the instrument prepared either from (a) stock solution(s) or from a (certified) reference material

由标准物质或者有证物质配制的用于仪器校正的溶液

3.1.5 certified reference material有证标准物质

reference material, accompanied by documentation issued by an authoritative body and providing one or more specified property values with associated uncertainties and traceabilities using valid precedures

附有证书的参考物质,它的一项或多项属性通过认可程序的验证,可以追溯到所表述属性值单位的真实准确度,而且每个验证值在所述的置信水平下都附有不确定度

3.1.6 laboratory control sample实验室质控样

known matrix spiked with compound(s) representative of the target analytes, used to document laboratory performance

已知基质中加入有代表性的目标物质,用来监控实验室的水平

[SOURCE: US EPA SW-846] [2]

3.1.7 reagent blank solution试剂空白样品

prepared by adding to the solvent the same amounts of reagents as those added to the test sample solution (same final volume)

制备通过向溶剂中加入相同量的试剂作为附加的测试样品溶液(最终体积相同)

3.1.8 stock solution储备溶液

solution with accurately known analyte concentartion(s), prepared from “pure chemicals”

由“纯化学物质”配制的准确的已知被分析物浓度的溶液

3.1.9 test portion被检部分

quantity of material drawn from the test sample (or from the laboratory sample if both are the same) and on which the test or observation is actually carried out

从测试样品中提取的被实际测试或观察的材料(或如果样品相同也可以从实验室提取)[SOURCE ISO 6206:1979] [3]

3.1.10 test sample solution测试样品溶液

solution prepared with the test portion of the test sample according to the appropriate specifications such that it can be used for the envisaged measurement

根据测试样品相应的规格所配制的测试溶液,这个溶液可以用于预期的测试

3.2 Abbreviations

CRM Certified reference material

CCFL Cold cathode fluorescent lamp

CCV Continuing calibration verification

CV-AAS Cold vapour atomic absorption spectrometry

CV-AFS Cold vapour atomic fluorescence spectrometry

LCS Laboratory control sample

LOD Limits of detection

LOQ Limits of quantification

MDL Method detection limit

TD(G)-AAS Thermal decomposition – Gold amalgamation – Atomic absorption spectrometry CRM 有证参考物质

CCFL 冷阴极荧光灯

CCV 校正核查物质

CV- AAS 冷蒸汽原子吸收光谱法

CV- AFS 冷蒸汽原子荧光光谱法

LCS 实验室质控样品

LOD 检出限

LOQ 定量限

MDL 方法检出限

TD(G) – AAS 热分解-金汞齐化原子吸收光谱法

4 试剂和材料

4.1 General概述

For the determination of elements at trace level, the reagents shall be of adequate purity. Contamination can be a major source of error when working in the 1 ng range with the instruments. Cautious handling of the apparatus and careful technique will minimize this problem. Therefore, only grade 1 water (4.2 a) shall be used. Care shall be taken that all materials in ontact with the water are Hg-free.

因为待测元素是痕量级的,所以试剂应具有足够纯度。当仪器使用的工作范围在1 ng 时,污染物可能是误差的主要来源。谨慎操作仪器和精确的技术将降低此问题。因此,应只使用1 级水(4.2 a),所有接触水的材料都应注意是无Hg 的。

Chemicals used for sample preparation can be a major source of contamination. Only reagents that are mercury-free shall be used. It is therefore highly recommended that the blank values of the reducing agents and the other chemicals be measured before using them for sample preparation.

制备样品的化学药品可能是污染的主要来源,所以只能使用无Hg的试剂。所以强烈建议在使用还原剂及其它化学药品制备试样之前检测它们的空白值。

4.2 reagents试剂

The following reagents are used:使用以下试剂:

a) Water: Grade 1, as defined in ISO 3696, shall be used for preparation and dilution of all sample solutions. 水:1级水,ISO 3696 确定的,用于制备及稀释所有的样品溶液。

b) Nitric acid (concentrated nitric acid): ρ(HNO3 )=1,4g/ml , a mass fraction of 65%, trace metal grade. 硝酸(浓硝酸):ρ(HNO3 ) = 1.4g/mL,65%(m/m),“痕量金属”级。

c) Nitric acid, a mass fraction of 50 %, trace metal grade. c) 硝酸,50%(m/m),“痕量金属”级。

d) Nitric acid, 0,5 mol/l, trace metal grade.硝酸,0.5 mol/L,“痕量金属”级。

e) Nitric acid, a mass fraction of 1 %, trace metal grade.硝酸,1%(m/m),“痕量金属”级。

f) Nitric acid, a mass fraction of 1,5 %, trace metal grade.硝酸,1.5%(m/m),“痕量金属”级。

g) Nitric acid, a mass fraction of 5 % , trace metal grade.硝酸,5%(m/m),“痕量金属”级。

h) Fluoroboric acid: HBF4,a mass fraction of 50 %, trace metal grade (for microwave digestion).四氟硼酸:HBF4 ,50%(m/m),“痕量金属”级(用于微波消解)。

i) Hydrogen peroxide: H2O2,a mass fraction of 30 %, trace metal grade (for microwave digestion).过氧化氢:H2O2 ,30%(m/m),“痕量金属”级(用于微波消解)。

j) Stock solution with 1000 mg/L of mercury, trace metal grade.

含Hg1000mg/kg 的标准溶液,“痕量金属”级。

k) Potassium tetrahydridoborate (potassium borohyride): KBH 4 , trace metal grade.

四氢硼酸钾:KBH 4 ,“痕量金属”级。

l) Potassium permanganate: KMnO4 , a mass fraction of 5% solution, trace metal grade.Dissolve 5 g of potassium permanganate in 100 ml of water (4.2 a).高猛酸钾:KMnO4,5%溶液(m/v),“痕量金属”级。将5 g高猛酸钾溶解于100mL水(4.2 a)中。

m) Sodium tetrahydridoborate (sodium borohydride), NaBH4 , trace metal grade.

四氢硼酸钠:NaBH4 ,“痕量金属”级。

n) Sodium hydroxide, NaOH trace metal grade. 氢氧化钠,NaOH(“痕量金属”级)。

o) Hydrogen tetrachloroaurate (Ⅲ) tetra hydrate, HAuCl4?4H2O trace metal grade.

四氢氯金(Ⅲ)四水合物,HAuCl4·4H2O,痕量金属级。

p) Internal standard stock solution, trace metal grade:内标准溶液:

– Internal standard elements that do not interfere with the target element are used for ICP-OES and ICP-MS. Also, the presence of these internal standard elements in the sample solution shall be at negligible levels. Sc, In, Tb, Lu, Re, Rh, Bi and Y may be used as internal standard elements. –用于ICP-OES 和ICP-MS 之内标准元素不得干扰待测元素。此外,存在样品溶液中的这些内标准元素应达到可忽略程度,Sc、In、Tb、Lu、Re、Rh、Bi 和Y 可以作为内标准元素使用。

– For use with ICP-OES, Sc or Y is recommended. The recommended concentration is 1000 mg/L. –Sc和Y建议用于ICP-OES,建议浓度是1000 mg/L。

– For use with ICP-MS, Rh is recommended. The recommended concentration is 1000 μg/l.

–Rh建议用于ICP-MS,建议浓度是1000μg/L。

q) Reducing agent for CV-AAS: a mass fraction of 3 % NaBH4 in a mass fraction of 1 % NaOH.

CV-AAS 还原剂:3%(m/v)NaBH4溶于1%(m/v)NaOH

Dissolve 10,0 g sodium hydroxide (4.2 n) into approximately 700 ml of water (4.2 a) in a beaker and stir until dissolved. Add 30,0 g of sodium tetrahydridoborate powder (4.2 m) into the beaker and stir until dissolved. Finally transfer to a 1 l volumetric flask and fill up to the mark with water (4.2 a) and filter. Prepare daily.

10.0 g氢氧化钠(4.2 n)至烧杯中加入约700毫升的水(4.2 a)搅拌至溶解,然后加入30.0 g四氢硼酸钠(4.2 m),搅拌至溶解,最后转移至1L的容量瓶中加水(4.2 a)至刻度线并过滤。每日制备。Reductant solution containing sodium tetrahydridoborate in a sodium hydroxide solution is recommended. If the available mercury hydride system is incompatible with this reductant, tin (II) chloride or stannous sulfate can be used instead. The instructions given in the operator’s manual for the instrument should be followed.

还原剂溶液建议在氢氧化钠溶液中含有四氢硼酸钠,如果Hg氢化系统不能处理此还原剂, 氯化锡(II)或硫酸亚锡可以用来代替,应遵守仪器操作手册上的指示。

r) Reducing agent for CV-AFS: a mass fraction of 1 % (m/v) KBH4 in a mass fraction of 0,05 %

NaOH. CV-AFS 还原剂:1%(m/v)KBH4溶于0.05%(m/v)NaOH

Dissolve 0,50 g sodium hydroxide (4.2 n) into approximately 700 ml of water (4.2 a) in a beaker and stir until dissolved. Add 10,0 g of potassium tetrahydridoborate (4.2 k) into the beaker and stir until dissolved. Finally transfer to a 1 l volumetric flask and fill up to the mark with water (4.2

a) and filter. Prepare daily.

0.5 g氢氧化钠(4.2 n)至烧杯中加入约700毫升的水(4.2 a)搅拌至溶解,然后加入10.0 g四氢硼酸钾(4.2 k),搅拌至溶解,最后转移至1L的容量瓶中加水(4.2 a)至刻度线并过滤。每日制备。Reductant solution containing potassium tetrahydridoborate in a sodium hydroxide solution is recommended. If the available mercury hydride system is incompatible with this reductant, tin (II) chloride or stannous sulfate can be used instead. The instructions given in the operator’s manual for the instrument should be followed.

还原剂溶液建议在氢氧化钠溶液中含有四氢硼酸钠,如果Hg氢化系统不能处理此还原剂, 氯化锡(II)或硫酸亚锡可以用来代替,应遵守仪器操作手册上的指示。

s) Gold preservation stock solution for mercury (1 ml = 100 μg): it is recommended purchasing as high purity prepared solution of AuCl3 in dilute hydrochloric acid matrix.

黄金保护的汞储备溶液(1ml = 100μg):推荐购买高纯度的AuCl3在稀盐酸基质中的配制的溶液。

t) Diatomaceous earth Analytical grade reagents may be used as an alternative except when utilizing ICP-MS methods.

硅藻土分析纯试剂可作为替代,除非利用ICP-MS的方法。

4.3 Materials 材料

Materials include:材料包括:

a) Mercury collector for thermal–decomposition-gold amalgamation system

汞收集器,热解析金汞齐化系统

A solution of 1 g of hydrogen tetrachloroaurate(Ⅲ) tetra hydrate (4.2 o) in 20 ml to 30 ml of water (4.2 a) is added to 3 g of 420 μm to 590 μm diatomaceous earth, which is then mixed until homogeneous. After being dried at approximately 80 °C, the collector is loaded into a tube furnace and heated for 30 min at around 800 °C in flowing air.

1克的氢四氯金(Ⅲ)的四水合物(4.2 O)溶于20毫升至30毫升水(4.2 a)中,加入3克420微米到590微米的硅藻土,然后将其混合直至均匀。在约80℃下干燥后,收集器被装入管式炉中,在800℃左右流动的空气中加热30分钟。

5 Apparatus设备

The following apparatus shall be used:应使用以下设备

a) Analytical balance capable of measuring accurately to 0,000 1 g.分析天平,精确度到0.0001 g For wet digestion as described in 7.1:用于7.1湿化消解法

b) Heating digester equipped with reaction vessels, reflux coolers and absorption vessels (for the digestion of metals and electronics).加热式消解器:配有反应瓶、回流冷却装置和吸收容器(为了消解金属及电子装置)

c) Glass fibre filter 0,45 μm.玻璃纤维过滤器0.45μm、

For microwave digestion as described in 7.2:用于7.2微波消解

d) Microwave sample preparation system equipped with a sample holder and high-pressure polytetrafluoroethylene/tetrafluoroethylene modified (PTFE/TFM) or perfluoro alkoxyl alkane resin /tetrafluoroethylene modified (PFA/TFM) or other vessels based on fluorocarbon materials (for the digestion of metals containing significant amounts of silicon (Si), zirconium (Zr), hafnium (Hf), titanium (Ti), tantalum (Ta), niobium (Nb) or tungsten (W), and for plastics).

微波试样制备系统:装有样品固定器和聚四氟乙烯/四氟乙烯(PTFE/TFM)或全氟烷氧基聚合物/四氟乙烯(PFA/TFM)或其它碳氟化合物材料的高压容器(为了消解金属所含重要成分硅(Si)、锆(Zr)、铪(Hf)、钛(Ti)、钽(Ta)、铌(Nb)或钨(W),以及塑胶);

e) Glass microfibre filter (borosilicate glass), pore size: 0,45 μm and a suitable filter cup.

玻璃超纤维过滤器(硼硅酸盐玻璃),孔径0.45μm与一只合适的过滤杯。

f) Volumetric flasks such as 25 ml, 250 ml , etc. (PTFE-PFA equipment or glassware).

容量瓶如25 mL、250 mL 等(PTFE/PFA 或玻璃制品)。

Where appropriate, other types of volumetric equipment with acceptable precision and accuracy can be used as alternatives to volumetric flasks.

合适的话,具有可接受精密度与精确度的其他类型的容器可取代量瓶。

g) Pipettes such as 1 ml, 2 ml, 5 ml, 10 ml, etc. (PTFE-PFA equipment or glassware).

吸液管如1 mL、2 mL、5 mL、10 mL 等(PTFE/PFA 或玻璃制品)

h) Micropipettes such as 200 μl, 500 μl, 1 000 μl, etc.

微量吸液管如200μl、500μl、1000μl 等。

i) Plastic containers for standards and digestion solutions. (PTFE-PFA equipment).

用于标准溶液及消解溶液的塑料容器(PTFE/PFA 或玻璃制品)

j) Cold vapour atomic absorption spectrometer (CV-AAS).

冷蒸气原子吸收分光光谱仪(CV-AAS)。

k) Cold vapour atomic fluorescence spectrometer (CV-AFS).

冷蒸气原子荧光分光光谱仪(CV-AFS)。

l) Inductively coupled plasma optical emission spectrometer (ICP-OES).

电感耦合等离子体原子发射光谱仪(ICP-OES)。

m) Inductively coupled plasma mass spectrometer (ICP-MS).

电感耦合等离子体质谱仪(ICP-MS)

n) Argon gas with a purity of at least 99,99 %.

氩气,纯度超过99.99%(v/v)。

o) Thermal decomposition-gold amalgamation system.

热解析金汞齐化系统

6 Sampling and test portion 取样和测试部分

The different test methods, which can be used as alternatives according to this standard,need different amounts of sample to obtain the required quality of results.

根据本标准可以选择使用不同的分析程序。为了保证分析结果的可靠需要的样品量不同。In the case of electronics, the sample shall first be destroyed mechanically by appropriate means (e.g. grinding, milling, mill cutting with LN2 -cooling due to volatility of mercury) before chemical dissolution of the powder can start. To ensure representative sample taking at this stage, a certain particle size as a function of the starting amount of sample is required (see IEC 62321-2). 对于电子装置,首先在化学消解前应以适当的机械性方法(如研磨、粉碎、切割)破坏试样使成为粉末。为了保证在此步骤取得代表性试样,以一定颗粒尺寸作为试样起始总量函数是必要的(参见IEC 62321-2)。

For the determination of mercury in fluorescent self ballasted lamps, single capped compact florescent multi lamps and linear fluorescent lamps, follow the instructions given in IEC 62554.

对于自镇荧光灯,单节荧光灯和多节荧光灯中汞的测定,依照IEC62554中所给程序。

If using a thermal decomposition-gold amalgamation system, samples should be milled in a ball mill and homogenized in advance. Difficult samples, like metals, to be ground as finely as possible. Put 50 mg to 200 mg of the sample into a sample boat. If using an additive, spread 0,5 g in a thin layer over the surface of the sample boat, evenly spread the sample over the additive, and then cover the sample with 2 g of additive.

如果使用的热解析金汞齐化系统,样品应预先在球磨机中研磨并均匀化。难研磨的样品,例如金属,应该尽可能的精细。把50毫克到200毫克的样品放入样品器皿。如果使用助剂,薄薄的散布0.5g至样品器皿中,在助剂上均匀的涂抹样品,然后再覆盖2g的助剂。

It is recommended to analyse aqueous sample solutions containing mercury preferably directly after sample preparation. If this is not possible, it is highly recommended stabilizing the solutions in an adequate way, and to store the solutions no longer than 28 days at ambient temperature.

建议最好在样品制备之后立即分析含汞的样品溶液。如果不能够立即分,那么溶液必须在一个合适的方式下足够稳定,并在环境温度存储的溶液不超过28天。

7 Procedure 程序

7.1Wet digestion (digestion of electronics) 湿法消解(消解电子装置)

Wet digestion is recommended for the digestion of metals and electronics, with the exception of metals containing significant amounts of Si, Zr, Hf, Ti, Ta, Nb or W. For these materials and for polymers, microwave digestion, as described in 7.2, is recommended.

湿法消解建议用于金属材料和电子装置的消解。除了含有大量Si、Zr、Hf、Ti、Nb或W的金属材料,对于这些金属和聚合物,推荐用7.2 描述的微波消解。

a) Weigh 1 g of a sample to the nearest 0,1 mg into the reaction vessel and 30 ml concentrated

nitric acid (4.2 b) is added. (When the available sample amount is 500 mg or less, refer to the instructions given in 7.2 a).

称大约1 g 的样品放入反应皿,加30mL 浓硝酸(4.2.b)。(当可获得的样品总量为500mg 或更低,则依照7.2.a 指示。)

The vessel is equipped with a reflux cooler and an absorption vessel (on top of the reflux cooler –see Figure A.1) containing 10 ml 0,5 mol/l nitric acid (4.2 d). A temperature program is then started to digest the samples for 1 h at room temperature and for 2 h at 90 °C.

反应皿装有回流冷却装置及配有10ml 0.5mol/L硝酸溶液(4.2.d)的吸收装置(在回流冷却装置顶部-见附录A中图A.1)。执行程序升温为:在室温下消解一小时,然后在90℃下消解两小时。

After cooling to room temperature, the contents of the absorption tube are placed in the reaction vessel and the solution obtained is transferred to a 250 ml volumetric flask (5.2 f) and filled with 5 % nitric acid (4.2 g) to the mark (if the sample is digested completely).

冷却至室温,吸收管的容量计入反应装置,获得的溶液转入250 mL 容量瓶(5.2 f)中(如果试样被彻底消解),加入5%(m/m)的硝酸(4.2 g)至刻度。

b) For ICP-OES and ICP-MS measurements, the sample solution obtained may be diluted with water (4.2 a) to the appropriate concentration levels for measurements. Add 250 μl of internal standard (4.2 p) for a volume of 250 ml before filling to the mark.

采用ICP-OES 和ICP-MS 方法,样品溶液可以用水(4.2 a)稀释至适当浓度进行测试。在250 mL 填满至刻度前加入250μl内标准溶液(4.2 p)。

c) If the sample is not completely digested (e.g. printed wiring boards), the sample is filtered with a filter (5.2.e) and the solid residue is washed four times with 15 ml 5 % nitric acid (4.2.g). The solution obtained is transferred to a 250 ml volumetric flask (5.2.f) and filled with 5 % nitric acid (4.2 g) to the mark.

如果试样未完全消解(如印刷电路板),试样用过滤器(5.2.e)过滤,且固体残留物用15ml 5%(m/m)的硝酸(4.2.g)清洗四次。获得溶液转入250mL 容量瓶(5.2.f)中,加入5%(m/m)的硝酸(4.2.g)至刻度。

d) Any sample residues shall be separated by a centrifuge or a filter. The residues shall be tested by appropriate measurements (e.g. XRF, alkali fusion method, other acid digestion methods, etc.) to confirm the absence of target elements. The instruction for XRF is given in IEC 62321-3-1.

任何样品遗留物都应用离心机或滤纸将它们分离。残渣应用合适的测量手段(如XRF、碱熔法,其他酸消解方法等)来检测以确定不含目标元素。XRF方法介绍见IEC62321-3-1。

7.2Microwave digestion微波消解

Microwave digestion is recommended for the following materials: 微波消解建议用于以下材料– metals containing significant amounts of Si, Zr, Hf, Ti, Ta, Nb or W,

含有大量Si、Zr、Hf、Ti、Nb 或W 的金属材料。

– polymers,聚合物

in cases where the available sample amount is smaller than 500 mg.It is highly recommended that the same sample amounts and the same type of samples be weighed in one digestion run.

可获得样品量少于0.5g的情况。在一次消解试验运行中,强烈建议试样类型相同且试样量相同。

NOTE 1 Mercury can be determined in the same solution with Pb and Cd obtained in a closed system for acid decomposition, as described in IEC 62321-5 [4].

注1 Hg可由IEC 62321-5 [4]描述的密闭系统酸分解获得的含Pb 和Cd 的同一溶液来测定。

a) Weigh, 0,1 g of a sample to the nearest 0,1 mg into a PTFE-TFM or PFA-TFM vessel. Add 5 ml of concentrated nitric acid (4.2 b), 1,5 ml 50 % HBF4 solution (4.2 h), 1,5 ml 30 % H2O2(4.2 i) and 1 ml water (4.2 a). Close the vessel and digest the sample in the microwave oven following a digestion program specified in advance. An example of a suitable microwave program is given in Annex A.

称约100 mg 材料置于PTFE-TFM 或PFA-TFM 消解容器中。加入5 mL 浓硝酸(4.2 b),1.5 mL HBF4溶液(4.2 h),1.5 mL 30%(m/m)H2O2 (4.2 i)和1 mL 水(4.2 a)。封闭消解瓶并在微波下按照预先设计的消解程序消解试样。附录A提供了一种合适的微波消解程序。

NOTE 2 If HBF4is not available in sufficient purity, HF may be used as an alternative.

如果HBF4纯度不够,可用HF 代替。

Hydrogen peroxide should only be added when the reactive components of the sample are known. Hydrogen peroxide may react rapidly and violently with easily oxidizable materials and should not be added if the sample contains large quantities of easily oxidizable organic constituents.

只有在知道样品的活性成分时才能添加过氧化氢。过氧化氢可与易氧化材料发生快速而猛烈的反应。当样品中可能含有大量易氧化有机成分时,不要添加过氧化氢。

b) Cool the vessel to room temperature (approximately 1h). Open the vessel, filter the solution with filter (5.2.e) into a 25ml flask (5.2.f), wash with water (4.2.a) and fill to mark with water (4.2 a).

消解罐冷却至室温(大约需要时间:1 h),打开它,用过滤器(5.2.e)过滤溶液后,转入25 mL 容量瓶(5.2.f)中,用水(4.2.a)清洗并用水(4.2.a)定容至刻度。

c) Any sample residues shall be separated by a centrifuge or filter. The residues shall be checked by appropriate measurements (e.g. XRF, alkali fusion method, other acid digestion methods, etc.) to confirm the absence of target elements. The instruction for XRF is given in IEC 62321-3-1.

任何样品遗留物都应用离心机或滤纸将它们分离。残渣应用合适的测量手段(如XRF、碱熔法,其他酸消解方法等)来检测以确定不含目标元素。XRF方法介绍见IEC62321-3-1。

The resulting concentrated solutions may be measured directly by ICP-OES and ICP-MS, i.e.the digestion solution may be analysed without any further sample preparation. When using CV-AAS and CV-AFS, the mercury is reduced to its elemental state before it is analysed.

使用ICP-OES和ICP-MS,直接测量浓缩溶液,也就是,消解溶液不需要进一步处理就可以分析。当使用CV-AAS和CV-AFS时,Hg在分析之前被还原成元素的状态。

7.3 Thermal decomposition-gold amalgamation system 热解析金汞齐化系统

The procedure should be performed as follows, but also follow the instruction manual of the relevant instruments for details on their operation:应该执行的程序如下,但也遵循的操作手册相关仪器操作的详细资料:

a) Place the sample vessel charged with a sample in position in the automatic sample changer.

将样品容器放在自动进样处

b) Set the predetermined temperature ramp program and raise the temperature of the sample heating furnace.

设置规定的升温程序并将样品加热炉加热

c) The mercury, mercury compounds and combustion product gases generated from the sample will be decomposed in the decomposition furnace containing the catalyst and then scrubbed and dehumidified in the gas washing bottle and the dehumidifier bottle.

汞、汞化合物和样品燃烧产生的气体,在含有催化剂的分解炉中分解,然后在洗气瓶和除湿瓶中冲洗并除湿。

d) The mercury and other gases are introduced into the mercury collecting tube, where only mercury is trapped in the form of amalgam, and any other gases discharged through the switching valve.

汞和其他气体引入水银收集管,只有汞以汞合金的形式被收集,其他任何其它气体,通过切换阀排出

e) The mercury collecting tube is heated at a constant temperature of 350 °C to 600 °C, and the generated mercury introduced into the absorption cell or the fluorescence cell. The height or area of the absorption peak or the fluorescence intensity is then measured at a wavelength of 253,7 nm.

水银收集管加热恒温350°C到600°C,生成的汞进入吸收池或荧光池。在波长的253.7nm 测定吸收峰和荧光强度

7.4Preparation of reagent blank solution 制备实验室试剂空白

The procedure is identical to that of sample preparation and is carried out concurrently but without the sample.

程序与样品制备相同,不加入样品同时进行。

8 Calibration校正

8.1General概述

All analyses require that a calibration curve shall be prepared to cover the appropriate concentration range. Calibration solutions are prepared by diluting the stock solution (4.2 j) with 1,5 % nitric acid (4.2 f). When internal standard methods (ICP-OES and ICP-MS) are used, the appropriate amounts of solution for the internal standard stock solutions (4.2 p) are added.

任何分析都要求一条覆盖适当浓度范围的校准曲线。校准溶液用1.5%(m/m)硝酸(4.2 f)稀释储备溶液(4.2 j)获得。当使用内标法(ICP-OES 和ICP-MS)时,加入适当量的内标准溶液(4.2 p)。Prepare a reagent blank solution of 1,5 % nitric acid (4.2 f) and at least three calibration solutions in graduated amounts in the appropriate range of the linear part of the calibration curve.

用1.5%(m/m)硝酸(4.2 f)制备试剂空白,并且至少制备三个校准溶液,以确立校准曲线适当的线性范围部分。

Calibration solutions shall be stored in mercury-free plastic containers. The stock solution (4.2 .j) is usually stable for at least a year, whereas calibration solutions shall be prepared daily.

标准溶液应储存于内壁为无Hg 塑料的容器中。标准溶液(4.2 .j)通常在至少一年内是稳定的,然而校准溶液应每天制备。

The stability of mercury calibration solutions can be severely affected by adsorption on the walls of the storage vessel. Therefore, it is recommended that mercury calibration solutions be stabilized by the addition of a few drops of 5 % KMnO4 (4.2 l) solution.

储存容器内壁的吸附作用显著影响Hg 标准溶液的稳定性。因而,建议加入几滴

5%(m/m)KMnO4(4.2 l)溶液以稳定该标准溶液。

NOTE A 1 % gold (Au) solution can also be used instead of potassium permanganate.

备注:1%(m/v)金(Au)溶液也可以用来代替高锰酸钾。

8.2Development of the calibration curve 建立校准曲线

The spectrometers are prepared for quantification with a reagent blank solution and a minimum of three calibration solutions. 用试剂空白和至少三个标准溶液校准仪器。

a) CV-AAS

1) The readings for the absorbance of the target element mercury are determined. The calibration curve obtained shows the relationship between the absorbance of mercury and its concentration.

测定目标元素Hg 的吸光度读数。校准曲线显示Hg 的吸光度和它的浓度之间的关系。

2) The recommended wavelength and examples of workable instrument parameters are listed in Clause A.3.

推荐波长和可使用的仪器参数列于附录A.3

b) CV-AFS

1) The readings for the fluorescence intensity of the target element mercury are determined. The calibration curve obtained shows the relationship between the fluorescence intensity of mercury and its concentration.

测定目标元素Hg 的荧光强度读数。校准曲线显示Hg 的荧光强度和它的浓度之间关系。2) The recommended wavelength and examples of workable instrument parameters are listed in Clause A.3.

推荐波长和可使用的仪器参数列于附录A.3

c) ICP-OES

The readings for the emission intensity of the target element mercury and those of the internal standard are determined. The calibration curve obtained shows the relationshipbetween the ratio of emission intensities of mercury and those of the internal standard to the concentration of mercury.

测定目标元素Hg 和那些内标准的散射强度读数。校准曲线显示Hg 的散射强度与内标准的比值和的Hg 浓度之间的关系。

The recommended wavelength for mercury and examples of workable instrument parameters are listed in Clause A.3.

推荐Hg 的波长和可使用的仪器参数列于附录A.3

d) ICP-MS

The readings for the mass/charge (m/z) intensity of the target element mercury and those of the internal standard are determined. The calibration curve obtained shows the relationship between the intensity ratio of the m/z of mercury and that of the internal standard to the concentration of

mercury.

测定目标元素Hg 和那些内标准的质/荷(m/z)比强度读数。校准曲线显示Hg 的m/z比与内标准的比值和的Hg 浓度之间的关系。

The recommended m/z ratios for mercury and examples of workable instrument parameters are listed in Clause A.3.

推荐Hg 的m/z 比和可使用的仪器参数列于附录A.3

e) TD(G)-AAS

Four or five calibration solutions, including a blank calibration solution, are placed directly into the sample boats using a micro pipette while changing the amount but ensuring it is within the working measurement range, and measured in the same manner as samples. A calibration curve is then derived from the relationship between the amounts of mercury and indicated values. For example, in the case of a sample’s mercury concentration being around 10 mg/kg, use 50 μl, 100 μl, 150 μl and 200 μl of 100 μg/ml stock solution for measurement and develop a calibration curve from the results obtained.

四或五个校正溶液,包括空白校正溶液,被直接放置于样品容器中,使用微量吸管改变进样量,但是必须确保在其工作范围内,以同样的方式处理样品。校准曲线是来自于汞的含量和指示值之间的关系。例如,在一个样品的汞浓度为10 mg/kg左右的情况下,使用50μl,100μl,150μl和200μl的100μl/ml储备液建立的校准曲线,求得测量结果。

8.3Measurement of the sample

After development of the calibration curve, the reagent blank solution and the test sample solutions are measured. If the sample concentration is above the range of the concentration curve, the solution shall be diluted with 1 % nitric acid (4.2 e) to the range of the calibration curve and measured again.

建立校准曲线后,测试实验室试剂空白和样品溶液。如果样品溶液浓度超出校准曲线的浓度范围,应用1%(m/m)硝酸(4.2 e)稀释至校准曲线浓度范围内再重新测试。

Measurement precision and baseline drift shall be checked with a standard substance, calibration solution, etc. and a blank calibration solution at regular intervals (such as every 10 samples) and after the last sample.

测量精密度通过按次序间隔(如每隔10 个样品)用标准物质、校准溶液检查。如必要,则重新制作校准曲线。

If the sample is diluted to the range of calibration, it should be ensured that the internal standard concentration in the diluted sample solution is adjusted to the standard solution.

如果样品稀释至校准曲线浓度范围,需要确定稀释后的样品溶液中的内标准溶液浓度与标准溶液相适应

9 Calculation计算

The concentration measured in 8.3 is the concentration of mercury in the sample solution. The concentration of mercury in the sample is calculated from the following formula:

8.3中测得的是样品溶液中Hg 的浓度。样品中Hg 的浓度用下式计算:

c=(A1-A2)×V /m

where

c is the concentration of mercury in the sample in μg/g;

c :样品中Hg 的浓度,单位μg/g;

A1 is the concentration of mercury in the sample solution in mg/l;

A1:样品溶液中Hg 的浓度,单位mg/L;

A2 is the concentration of mercury in the reagent blank solution in mg/l;

A2:实验室试剂空白中Hg 的浓度,单位mg/L

V is the total volume for the sample solution in ml which depends on

V:样品溶液总体积,单位mL,取决于

– the type of digestion carried out (250 ml for wet digestion, 25 ml for microwave digestion), 采用的消解形式(湿法消解为250 mL,微波消解为25 mL)

– the type of the particular series of dilutions used;

采用的稀释级数

m is the measured quantity of the sample in g.

样品称重量,单位g。

10 Precision精密度

When the values of two independent single test results, obtained using the same method on identical test material in the same laboratory by the same operator using the same equipment within a short interval of time, lie within the range of the mean values cited in Table 1 below, the absolute difference between the two test results obtained will not exceed the repeatability limit, r, deduced by statistical analysis on the international interlaboratory study Nos. 2 (IIS2) and 4A (IIS 4A) results in more than 5 % of cases (see Annex B).

当两个独立的测试结果是在一个短的时间间隔内使用相同的方法在同一实验室由同一操作,使用相同的设备在相同的试验材料获得的,下表1列举出了两个测试结果的平均值。两个测试结果的绝对差不能超过由国际实验室之间[2号(IIS2)和4A(IIS4A)]通过数据分析出的重复性限和r值的5%(见附件B)

When the values of two single test results, obtained using the same method on identical test material in different laboratories by different operators using different equipment, lie within the range of the values cited Table 1 below, the absolute difference between the two results will not be greater than the reproducibility limit R by statistical analysis on interlaboratory study Nos. 2 (IIS2) and 4A (IIS 4A) results in more than 5 % of cases.

当两个独立的测试结果是在不同实验室由不同操作,采用相同的方法使用不同的设备在相同的试验材料获得的,下表1列举出了两个测试结果的平均值。两个测试结果的绝对差不能大于由国际实验室之间[2号(IIS2)和4A(IIS4A)]通过数据分析出的重复性限和R值的5%(见附件B)

Table 1 – Repeatability and reproducibility

表1—重复性和再现性

Material type 材料类型IIS

Technique

方法

Mean value

平均值(mg/kg)

r(mg/kg)R(mg/kg)

21.4 7

4.2 0.4

Insufficient data

数据不全

88.5 3.3 13.7

2

883.5 45.1 165.1

30 1.6 3.7

4A

CV-AAS

52.6 4.1 10.6

24.8 0.6

2

4.8 0.4

Insufficient data

数据不全

30 5.3 15.0

4A

CV-AFS

52.6 7.1 27.2

31.3 0.7 4.2

56.8 2.1 8.7

4A TD(G)-AAS

22.7 2.4 5.5

25.4 7.2

3.8 1.4

Insufficient data

数据不全

Polymer

聚合物

2 ICP-OES

90.7 8.8 23.1

901.7 116.2 192.7

注:由于参加国际实验室研究交流的实验室和样品的局限性,ICP-MS技术以及金属电子材料类型的重复性和再现性数据不可用。预计上面所示的那些类似结果为ICP-MS技术以及金属电子材料类型的。

11 Quality assurance and control质量保证和控制

11.1General 概述

Where applicable, the quality assurance and control clauses of the individual test method standards shall include control sample requirements regarding testing frequency and acceptance criteria. This clause shall also include method specific quality control concerns regarding the determination of limits of detection (LOD) and limits of quantification (LOQ).Where applicable, the LOD and LOQ section shall be consistent with the descriptions in 11.2.

在适用的情况下,个别测试方法标准的质量保证和质量控制条款应包括控制样品的测试频率和验收标准的要求。此条款也应包括具体的质量控制方法,特别关注的是检测限(LOD)和定量限(LOQ)的测定。在适用的情况下,LOD和LOQ的部分应该与1.2中的描述一致。Examples of other method specific quality control concerns include requirements regarding initial calibration verification, method blanks, laboratory control samples (LCS) and so forth are listed in Table 2.

关于其他方法具体的质量控制问题的例子包括要求初始校准验证,方法空白,实验室控制样品(LCS)等列于表2。

Table 2 – Acceptance criteria of items for the quality control

质量控制的验收标准

Items Concentration mg/kg in test

sample Acceptance criteria Calibration curve R2> 0.995

Initial calibration verification e.g.) 1 mg/kg for Hg Recovery: (90 to 110) %

Continuing calibration

Recovery: (90 to 110) % verification (CCV) e.g.) 1 mg/kg for Hg

Method blank < MDL

Laboratory control sample

Middle of calibration range Recovery: (80 to 120) % (LCS)

Laboratory control sample

Middle of calibration range Relative deviation <20 % duplicate

a) Initial calibration verification is performed whenever a calibration curve is established,using a standard from a source different than calibration standard.

在初始校准进行验证过程中,每当建立校准曲线时,都应该使用不同于源校准标准的标准。

b) One method blank should be analysed at once per a batch. A blank matrix which does not contain mercury can be used as a method blank sample.

每分析一个批次都应该分析一个方法空白。不含有汞的空白基质可以作为一个方法空白样品。

c) One laboratory control sample (LCS) and laboratory sample duplicate per batch, should be analysed by means of spiking mercury in the blank matrix. Alternatively, a certified reference material containing mercury can be tested in duplicate.

通过空白基质中汞的尖峰来分析一个实验室控制样品(LCS)和实验室重复的每批量样品。另外,一个认证的标准汞材料必须被同步测试两次。

d) After every tenth sample run and at the end of each sample set, analyse a continuing calibration verification standard (CCV). The percent recovery for mercury shall be between 90 % and 110 %. If the per cent recovery for mercury in the CCV standard falls outside of this range,

the CCV standard should be re-analysed within 12 h. If the recovery is still out of range after

re-analysis of the CCV standard, the analysis is stopped and maintenance shall be performed on the system to return it to optimal operating conditions. All samples loaded before the last successful CCV standard may be reported, but all samples after the failing CCV standard shall be re-analysed with a new calibration.

运行每十个样品和每个样品之后应分析持续校准检验标准(CCV)。对汞的回收率应该在90%和110%之间。如果汞的回收率不在上述范围之间,则CCV标准应该被从新分析在12h内。如果重新分析的汞的回收率在上述范围之间,则停止分析,维持系统恢复到最佳检测条件下。在最后成功的CCV标准报告之后,进行进样。但是CCV标准失败后,应该在新的标准下进行重新分析。

11.2Limits of detection (LOD) and limits of quantification (LOQ) 检测限(LOD)和定量限(LOQ)

The following experimental procedure is performed to determine the method detection limit and limit of quantification for mercury.

下面的实验程序是确定汞的方法的检出限和定量限。

a) Accurately weigh out the appropriate amount of sample known not to contain mercury

(e.g.certified reference materials) or other compounds that may interfere with the analysis according to the procedure of interest in Clause 7. Place the sample into each vessel (5.2.b or

5.2.d or 5.2.o). Repeat this step a minimum of 5 times.

准确称取适量不含有汞(如认证的参考材料)或含汞其他化合物的样品,根据第7条描叙的过程,可能会干扰分析。将样品放入每个容器(5.2 b或5.2 d或5.2 o)。重复此步骤,最少重复五次。

b) Spike each of the vessels with 10 μg mercury using the stock solution (4.2. j).

使用汞的储备液(4.2. j)向每个容器中加标10μg汞。

c) Follow the test procedure of interest in Clause 7 through the digestion and spectroscopic measurement.

按照测试程序条款7通过消化和光谱测量。

d) Calculate the mercury concentration (μg/g) as indicated in Clause 9 and determine the per

ent recovery of the spiked mercury for each of the samples.

根据以上条款9计算汞浓度(μg / g),确定的每个样品中汞的加标回收率。

SR=C×M/SA×100%

其中

SR is the rate of recovery in % of the spiked mercury; SR是汞的加标回收率

C is the measured concentration in μg/g; C是实测浓度μg / g;

M is the sample mass in g; M是样品质量g

SA is the spike amount (10 μg). SA是加标量

The per cent recovery of mercury shall be between 80 % and 120 % for each of the samples. If the recovery is outside the limits for any of the replicates, the entire extraction and analysis procedure shall be repeated.

每个样品中汞的回收率应在80%至120%范围内,如果任何一个重复样品的回收不在这个范围内,那么应重复整个提取和分析过程。

e) The method detection limit is obtained by calculating the standard deviation, s, for the

replicate (minimum of 6) analyses. The standard deviation is then multiplied by Student’s t value for the total number of replicates (n) for n-1 degrees of freedom. A list of Student’s t values for 6 to 10 replicates is shown in Table 3.

方法检出限是通过计算重复性(至少6次)分析的标准差。标准差乘以总数量为n,自由度为n-1的t值。6到10次重复性的t值入表3所示。

EXAMPLE For 6 replicates and 6 – 1 = 5 degrees of freedom, the t value would be 3.36.

例如:对于6次重复性和6 - 1 =5个自由度,t值取3.36。

NOTE All analyses used to calculate an MDL should be consecutive.

所有的分析中用于的MDL计算应该是连续的。

Table 3 – Method detection limit = t × s n–1

Number of samples

样本数Student’s t-statistic 99 % confidence t分布99%置信率

6 3.36

7 3.14

8 3.00

9 2.90

10 2.82

f) The limit of quantification is determined by multiplying the method detection limit by a factor of 5.

定量限是方法检出限的5倍。

Method detection limits and limits of quantification will vary from laboratory to laboratory. Generally, a method detection limit of 2 μg/g (limit of quantification of 10 μg/g) has been found achievable using this method, however, this value depends on each instrument.

方法检出线和定量限会由于实验室不同而不同。一般来说,使用这种方法可以达到方法检出限为2μg/g(定量限为10μg/g),但是,这个值也取决于每种仪器。

Annex A 附录A

(informative) 参考

Practical application of determination of mercury in polymers,metals and electronics by CV-AAS,

AFS, ICP-OES and ICP-MS

采用CV-AAS,CV-AFS,ICP-OES 和ICP-MS 测试聚合物、金属和电子装置中的汞的实际应用A.1 Equipment设备

Below is an example of the equipment used. 下面是使用的设备的一个例子。

Figure A.1 – Heating digester equipped with reaction vessel,reflux cooler and absorption vessel 图A.1 - 装有反应容器、冷凝回流装置和吸收容器的加热式消解器

Table A.1 – Program for microwave digestion (example)

of samples (power output for five vessels)

试样微波消解程序表(能量输出给五个容器)

Step 步骤Time (min)

时间(min)

Power output (W)

输出能量(W)

Pressure limited to

(Mpa)

压力限值(Mpa)

1 5 400 3.5

2 5 600 3.5

3 12 800 3.5

4 20 800 4.0

5 3 500 4.0

Ventilation step

通风步骤

20 0 -

A.2 Thermal decomposition-gold amalgamation system 热解析金汞齐化系统

A.2.1 General概述

The system is made up of a mercury removing filter, a sample heating furnace, a decomposition furnace, a cooling dehumidifier, a mercury collector furnace, an absorption cell for cold-vapor atomic absorption spectrometry or fluorescence cell for cold-vapor fluorescence spectrometry, a switching valve, a suction pump, a flow meter, etc. Some of these factors, however, such as the matrix effect, dilution factor and interferences reposed method should be confirmed.

该系统由除汞过滤器,样品加热炉,分解炉,冷却除湿机,汞收集管炉,冷蒸汽原子吸收光谱吸收池或冷蒸气荧光光谱荧光池,切换阀,吸入泵,流量计等组成。然而,其中的一些因素,如基体效应,稀释因子和方法干扰因素应该被确认。

Key

A mercury removal filter 除汞过滤器

B combustion tube燃烧管

C sample heating furnace样品加热炉

D decomposition furnace分解炉

E gas-washing bottle气体洗涤瓶

F dehumidifier bottle除湿瓶

G mercury collector furnace汞收集管炉

H mercury collecting tube汞收集管

I cold-vapor atomic absorption cell冷蒸汽原子吸收光谱吸收池

J switching valve切换阀

K mercury remover除汞剂

L suction pump真空泵

M flow meter流量计

Figure A.2 – Configuration of equipment with AAS (example)

图A.2设备配置- AAS(例如)

A.2.2 Carrier gas 载气

Air is typically used as the carrier gas. Oxygen-rich gas can also be used as a carrier gas. Oxygen can produce explosion-like rapid combustion in the sample heating furnace, resulting in a large amount of combustion products instantly appearing, which can exceed the catalyzing capability

of the downstream decomposition furnace, or part of the mercury generated in the decomposition may change into mercury oxide. The heating temperature and flow rate therefore need to be carefully selected. Ar gas is necessary specifically for the fluorescence spectrometry.

空气通常用作载气。富氧气体还可以用作载气。氧气会在样品加热炉中急速燃烧而产生爆炸。导致大量的燃烧产物出现,可能超过下游分解炉的催化能力,或部分分解中产生的汞可能变成氧化汞。因此,需要仔细选择加热温度和流速。对于荧光光谱仪来说,氩气是必要的。Any mercury in the carrier gas should be removed with a filter such as activated charcoal or gold mesh.

在载气中的汞应通过活性炭或金网的过滤器。

A.2.3 Heating unit加热装置

The combustion tube is made of ceramic or quartz. Sample vessels are made of heatproof materials. When liquid samples are analyzed, the vessel should be made of quartz or ceramic (mercury-free).

燃烧管是由陶瓷或石英制成。样品容器的耐热材料制成的。分析液体样品时,容器应采用石英或陶瓷(无汞)。

A.2.4 Decomposition furnace分解炉

A catalyst such as manganese oxide, copper oxide, cobalt oxide, or platinum is placed in the decomposition furnace within the combustion tube so as to decompose any organic substances and mercury compounds, thus requiring that the temperature and the carrier gas rate be carefully set in order to prevent mercury oxide being generated.

氧化锰,氧化铜,氧化钴,或铂作为催化剂被放置在分解炉的燃烧管内直至有机物质和汞化合物分解,因此为了防止所产生的汞氧化必须精心设置需要的温度和载气流速。

A.2.5 Washing and de humidifying equipment清洗和除湿设备

If the system has a cold spot in its plumbing and needs to dehumidify the moisture, cooled humidification involves easier handling and maintenance than de humidifiers that use desiccant such as magnesium perchlorate. More effective results are also obtained when a gas-washing bottle is used before de humidification takes place. Standard buffer solution should be used for gas washing.

如果系统有一个在其管道需要除湿的冷却点,使用干燥剂,如高氯酸镁冷却除湿处理和维护比除湿器更容易。当洗气瓶用于除湿前可以得到更好的效果。标准缓冲溶液应该用于气体洗涤。

A.2.6 Mercury collecting tube汞收集管

An example of the mercury collecting tube is given in Figure A.3.

图A.3中给出了汞收集管一个例子

A quartz glass tube that is dimpled in the middle is filled with quartz glass wool, mercury collector, and quartz glass wool, in that order.

石英玻璃管,按这个顺序在中间充满了石英玻璃棉、汞收集器、石英玻璃棉。

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合抱之木,生于毫末,九层之台,起于累土;千里之行始于足下。 A huge tree that fills one’s arms grows f rom a tiny seedling; a nine-storied tower rises from a heap of earth; a thousand li journey starts with the first step. 祸兮,福之所依;福兮,祸之所伏。 Misfortune, that is where happiness depends; happiness, that is where misfortune underlies. 见贤思齐焉,见不贤而内自省也。 On seeing a man of virtue, try to become his equal; on seeing a man without virtue, examine yourself not to have the same defects. 江山如此多娇,引无数英雄尽折腰。 This land so rich in beauty has made countless heroes bow in homage. 举头望明月,低头思故乡。 Raising my head, I see the moon so bright; withdrawing my eyes, my nostalgia comes around. 俱往矣,数风流人物,还看今朝。 All are past and gone; we look to this age for truly great men.

中文地址翻译成英文地址的方法和技巧

中文地址翻译成英文地址的方法和技巧 中文地址的排列顺序是由大到小,如:X国X省X市X区X路X号,而英文地址则刚好相反,是由小到大。如上例写成英文就是:X号,X路,X区,X市,X省,X国。 1.各部分写法 ●X室:Room X ●X号:No. X ●X单元:Unit X ●X楼/层:X/F ●X号楼:Building No. X ●住宅区/小区:ResidentialQuater ●X街:XStreet ●X路:XRoad East/Central/West东路/ 中路/ 西路 芙蓉西二路/ West 2nd Furong Road Central Dalian Rd. /大连中路 芙蓉中路的“中”可以用Central,也有用Middle的,一般用Mid比较简洁。 ●X区:XDistrict ●X镇:XTown ●X县:XCounty ●X市:XCity ●X省:XProvince ●国家(State)中华人民共和国:The People’s Republic of China、P.R.China、P.R.C.、 China ●X信箱:M ailbox X 请注意:翻译人名、路名、街道名等,最好用拼音。 各地址单元间要加逗号隔开。

2.英文通信地址常用翻译 201室/房Room 201 二单元Unit 2 马塘村MatangVallage 一号楼/栋Building 1 华为科技公司Huawei Technologies Co., Ltd.

xx公司xx Corp. / xx Co., Ltd. 宿舍Dormitory 厂Factory 楼/层Floor 酒楼/酒店Hotel 住宅区/小区Residential Quater 县County 甲/乙/丙/丁A/B/C/D 镇Town 巷/弄Lane 市City 路Road(也简写作Rd.,注意后面的点不能省略)一环路1st Ring Road 省Province(也简写作Prov.) 花园Garden 院Yard 街Street/Avenue 大学College/University 信箱Mailbox 区District A座Suite A 广场Square 州State 大厦/写字楼Tower/Center/Plaza 胡同Alley(北京地名中的条即是胡同的意思) 中国部分行政区划对照 自治区Autonomous Region 直辖市Municipality 特别行政区Special Administration Region 简称SAR 自治州Autonomous Prefecture

在线考试系统方案书

在线考试系统方 案 书

概述 传统的考试方式组织一次考试至少要经过人工出卷、考生考试、人工阅卷、成绩统计和试卷分析五个步骤。随着考试规模的不断扩大,工作量将会越来越大而且容易出错。因此开发一套在线考试系统具有重要的现实意义: 1、在线考试突破了时空限制。在线考试系统突破了传统考试模式的时间、空间的限制,有利于组织大规模异地实时考试,可以满足任何授权的考生在规定的时间段内在任意时间和可用地点参加考试,大大提高了教学内容和考核方式的灵活性。 2、提高了工作效率。在线考试系统减轻了考试主管部门人员尤其是教师在命题、组卷、阅卷等方面繁重的工作量,提高了工作效率。 3、节省财政开支。在线考试真正实现了无纸化办公,节省了纸张、印刷等考核费用。 系统总体设计思想 1、以提高教学效率为主要目的 在线考试系统提高了教学内容和考核方式的灵活性,减轻了出题、组卷、阅卷、试卷统计等繁重的工作量,增强了试卷批阅及试卷数据统计的客观公平性,实现了考试信息管理以及考试流程的系统化、规范化和自动化,大大提高了教学效率。 2、以安全稳定为系统设计指导思想 安全性是考试系统质量高低一个重要的检测标准。测试系统中的重要内容如试题、试卷、成绩、身份等信息都应高度保密,必须采取相关措施,为系统设置安全的入口,防止非法访问和非法攻击。 3、以智能便捷为系统设计原则 考试系统应融入智能化思想,组卷、阅卷等较繁琐的工作过程需要以较智能的形式呈现给用户,把大量的信息适当的分解后呈现给用户,使用户的操作有章可循,提高系统的便捷性。 主要模块设计及系统管理功能说明: 一、我的考试功能模块

我的考试分为参加考试,历史考试 1、参加考试功能分析:参加考试这块是给学生们考试用的,学生可以通过学号, 密码进入考试系统,并选择要考试的科目进行考试。实现了无纸化考试,提高了工作效率。考生点击“开始答题”按钮后,显示试卷内容,并且开始计时,考生在规定时间内没有交卷,时间到时就会强迫交卷;在规定时间内交卷,交卷后自动阅卷,考生可直接看到自己本次考试的成绩。 2、历史考试功能分析:历史考试是学生们以前考过的试卷以及成绩存档,方便学 生查看自己的成绩以及试卷具体的内容,使学生知道自己哪方面的知识掌握不牢错了。 并可以对自己成绩进行分析。 二、我的练习功能模块 我的练习功能就分为一个日常练习,这是供学生们在闲暇时间在线练习,巩固知识,这里面可以分科目进行练习。 三、考试管理功能模块 考试管理功能分为科目管理、题库管理、试卷管理、评分阅卷、成绩查询。 1、科目管理功能分析:在线考试时可以分科目进行的,在科目管理里面可以添加 科目,修改科目,删除科目。 2、题库管理功能分析:管理员对题库中科目,系别,题型进行添加,删除,修改,并对科目进行分类。老师可以对题库添加、删除、修改试题,可以选中对应的系别,科目,题型,添加试题进入题库,客观题可以输入正常答案。可以删除自己对应系别,科目下的试题和答案,可以修改自己对应系别,科目下的试题,答案。 扩展:1.即时检查一些主要信息是否为空,是否符合格式 2.可用excel导入试题 3、试卷管理功能分析:试卷管理是供教师管理的,教师可以在里面添加、修改、删除试卷的题型、科目、以及适合哪些班级考试。 4、评分阅卷功能分析:客观题部分,可以根据题库中的答案对比,直接算出学生得到的分数。系统对主观题有自动判分功能,但人为可以干预,在系统自动判分的基础上进行加分或减分。系统会地明细一一记录。对一些考试主观题进行批卷而设计,在本系统主要体现在“问答题”上。只有批改权限的人员才可以查看到相关数据。 注:考生信息:批卷人员无法查看到,为了防止打人情分作弊。

英文翻译成中文

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在线考试系统的设计和实现(毕设参考)

软件工程课程设计设计说明书 考试系统的设计与开发 学生姓名 学号 班级 成绩 指导教师 数学与计算机科学学院 2012年12月26日

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课程设计任务书 2012 —2013 学年第一学期 专业:学号:姓名: 课程设计名称:软件工程课程设计 设计题目:考试系统的设计与开发 完成期限:自2012 年12 月17 日至2012 年12 月28 日共 2 周设计依据、要求及主要内容(可另加附页): 指导教师(签字):教研室主任(签字): 批准日期:年月日

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1 课题描述 (3) 1.1 开发背景 (4) 1.2 系统开发目标 (4) 1.3 开发工具的选择 (4) 2 需求分析 (2) 2.1 背景分析 (2) 2.2 可行性分析 (2) 2.2.1 技术可行性分析 (2) 2.2.2 经济可行性 (2) 2.2.3 方案可行性 (2) 2.3 概要设计 (2) 2.4 总体设计 (3) 2.4.1 系统的功能模块图 (3) 2.4.2 系统功能模块 (4) 3 数据库设计 (5) 3.1数据字典 (5) 3.2 数据库的连接 (7) 4 详细设计 (8) 4.1 公共类设计 (8) 4.2 在线考试模块设计 (9) 4.3 查看考生试卷模块设计 (10) 4.4 考试设置信息维护模块设计 (10) 4.5 用户管理模块设计 (11) 5 程序调试与测试 (1) 5.1 系统运行环境 (1) 5.2 测试目的 (1) 5.3 各功能模块测试 (1) 5.3.1 在线考试模块测试 (1) 5.3.2 查看试卷测试 (2) 5.3.3 管理员模块 (3) 5.3.4 用户管理模块测试 (5) 总结 (7) 参考文献 (8)

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3.正确登录后,打开考生须知页面,仔细核对考生信息和阅读考场规则后,点选[我己仔细阅读考场规则]按钮,打开确认页面,点选开始考试,开始考试。考试过程中不允许进行回退操作(IE浏览器中←按钮)。 4.考生答题: 考生可以通过上下滚动条来浏览试题,直接点选正确的答案,即可完成答题。在考试页面左边列出考生相关信息,考试相关信息,考试剩余时间。 考生可以点选提交备份按钮手工保证考试现场,也可不点选,由系统自动备份(每2分钟自动备份一次),以便由意外原因,中断考试后重新进入时恢复考试现场。

5.考试完成后,可点选提交试卷——确认后交卷。也可由系统自动到时提交。 6.意外中断考试: 如考生意外中断考试,可重新登录,登录时显示如下对话框: 核对完考生信息后,选择确定按钮,系统将恢复考场至最近一次备份的现场(2分钟以内),考生可以继续进行考试。 三、上机操作考试 1.考生完成操作考试后,打开浏览器,输入地址:http://17 2.16.0.32:81/oppapers/

中文名字的英文写法

中文名字最标准的英文写法就是直接翻译成汉语拼音:Li Leyang或Lee Yeyang 西方人的习惯是名字在前,姓在后,二者间如果有中间名(Middle name),Middle name一般用简写,中国人如果有英文名字,在正式的场合可以参照这种格式。比如,搜狐创始人、董事局主席张朝阳的英文名字就写成:Charles CY. Zhang. 搜狐所有英文正式文件中张朝阳的名字都是这样写的。 如果没有英文名字,那么应该按照中国人的习惯(姓在前名字在后)直接把中文名字翻译成汉语拼音作为英文写法!很典型的例子,奥运会上,所有中国运动员的名字在运动衣上都是这样翻译的(以前不是,后来国家颁布了《汉语拼音方案》,并解释到《汉语拼音方案》是拼写中文人名地名唯一标准后,统一改过来了),所以,中国人名字的英文写法,就是汉语拼音:姓在前,名在后,姓和名分开写,姓和名的开头字母均大写! 两个字的是:比如:张三就应该写:Zhang San 三个字的是:1.单姓,比如:李小言就应该写:Li Xiaoyan 2.复姓,比如:诸葛亮就应该写:Zhuge Liang 四个字的是:1.单姓,比如:李雨中生就应该写:Li Yuzhongsheng 2.复姓,比如:司马相如就应该写:Sima Xiangru 1. Last Name就是姓,First Name就是名,請勿混淆。 2. "國語羅馬拼音對照表" 乃外交部護照科所採用的中英文姓名翻譯原則,為了保持所有文 件的統一,建議同學根據此表來翻譯姓名及地址。 3. 同學的英文姓名,應由中文姓名音譯,並與大學英文畢業證書、英文成績單、TOEFL / GRE / GMAT考試及申請學校、辦理護照及簽證時所用的英文姓名完全一致,如姓名不 一致,將造成申請學校、辦護照、簽證時身份的困擾,徒增麻煩。 4. 如果有英文別名 (如John、Mary...等),可以將別名當做Middle Name。 [例] 王甫平有一個英文別名STEVE,其英文姓名可以下列方式列出: WANG FUPING S Last Name First Name M.I. 5. 如果沒有英文別名,M.I. 處不要填。 6. 如非必要,英文別名最好不要用,只用中文姓名的英譯最為單純。 7. 在國外使用英文姓名的建議:外國人習慣將名放在前面,姓放在後;而中國人的姓名, 則是姓在前名在後,有時在國外填寫資料時常會搞錯,建議在打履歷表、印名片或處理 資料時,如果填寫姓名的地方沒有註明Last Name時,英文姓名正確表達方法可以如: Fuping Wang 或 Wang, Fuping

在线考试系统详细设计说明书

在线考试系统详细设计说明书

详细设计说明书 1引言 1.1编写目的 说明在线考试系统各部分的功能和结构,用于系统开发和便于公司技术人员以后的查询和维护工作以及用户使用。 1.2背景 随着网络技术的飞速发展,现在很多国外的大学和社会其它部门都已经开设了远程教育,经过计算机网络实现异地教育和培训。可是,远程教育软件的开发当前还处于起步阶段,随着这项技术的不断深入发展,就要求有更好、更完善的软件系统应用到远程教育当中去,这就给软件设计人员提出了更高的设计要求。 远程教育包括很多环节,例如教学系统、答疑系统和考试系统等等。其中很重要的一个环节就是在线考试系统,同时它也是最难实现的环节。在中国,虽然远程教育已经蓬勃地发展起来,可是当前学校与社会上的各种考试大都采用传统的考试方式,在此方式下,组织一次考试至少要经过五个步骤,即人工出题、考生考试、人工阅卷、成绩评估和试卷分析。显然,随着考试类型的不断增加及考试要求的不断提高,教师的工作量将会越来越大,而且其工作将是一件十分烦琐和非常容易出错的事情,能够说传统的考试方式已经不能适应现代考试的需要。随着计算机应

用的迅猛发展,网络应用不断扩大,如远程教育和虚拟大学的出现等等,且这些应用正逐步深入到千家万户。人们迫切要求利用这些技术来进行在线考试,以减轻教师的工作负担及提高工作效率,与此同时也提高了考试的质量,从而使考试更趋于公证、客观,更加激发学生的学习兴趣。例如当前许多国际著名的计算机公司所举办的各种认证考试绝大部分采用这种方式。 伴随着远程教育的蓬勃发展,作为教学当中不可分割的一部分的在线考试系统也得到了当今远程教育研究者的关注,考试是考察学生对所学习知识的接受和理解程度的重要手段,无纸化的考卷,考试的随时性,随地性,这些特点都是研究并开发网络考试系统主要的原因,网络考试系统远远超越了传统考试固定时间,固定地点的考试模式的限制,将给学生和老师带来极大的便利。随着Internet的相关技术的发展,特别是Web技术的出现,人们开始致力于研究和开发基于Internet考试系统,这也大大推动了远程教育的发展[2]。 如今世界上对于基于Internet的远程考试系统所进行的研究开发工作不是很长,可是基于web技术构建的在线考试系统已然成为发展的主流。数据库安全、共享、数据传输过程的安全性、访问控制技术、身份识别技术都是构建考试系统要考虑的问题。当前,一些远程教育机构已经开发出了在线考试系统,基本实现了基于Internet的B/S结构在线考试。经过Server端的后台试题库动态生成考卷和对于标准化的试题即时评定成绩。可是与传统

中文姓氏英文翻译

中文姓氏英文翻译 A: 艾--Ai 安--Ann/An 敖--Ao B: 巴--Pa 白--Pai 包/鲍--Paul/Pao 班--Pan 贝--Pei 毕--Pih 卞--Bein 卜/薄--Po/Pu 步--Poo 百里--Pai-li C: 蔡/柴--Tsia/Choi/Tsai 曹/晁/巢--Chao/Chiao/Tsao 岑--Cheng 崔--Tsui 查--Cha 常--Chiong 车--Che 陈--Chen/Chan/Tan 成/程--Cheng 池--Chi 褚/楚--Chu 淳于--Chwen-yu D: 戴/代--Day/Tai 邓--Teng/Tang/Tung 狄--Ti 刁--Tiao 丁--Ting/T 董/东--Tung/Tong 窦--Tou 杜--To/Du/Too

段--Tuan 端木--Duan-mu 东郭--Tung-kuo 东方--Tung-fang E: F: 范/樊--Fan/Van 房/方--Fang 费--Fei 冯/凤/封--Fung/Fong 符/傅--Fu/Foo G: 盖--Kai 甘--Kan 高/郜--Gao/Kao 葛--Keh 耿--Keng 弓/宫/龚/恭--Kung 勾--Kou 古/谷/顾--Ku/Koo 桂--Kwei 管/关--Kuan/Kwan 郭/国--Kwok/Kuo 公孙--Kung-sun 公羊--Kung-yang 公冶--Kung-yeh 谷梁--Ku-liang H: 海--Hay 韩--Hon/Han 杭--Hang 郝--Hoa/Howe 何/贺--Ho 桓--Won 侯--Hou 洪--Hung 胡/扈--Hu/Hoo 花/华--Hua 宦--Huan 黄--Wong/Hwang

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