原子荧光光谱测定土壤和水系沉积物中硒的干扰来源及消除方法

赵宗生; 赵小学; 姜晓旭; 赵林林; 张霖琳

doi:10.15898/j.cnki.11-2131/td.201809190106

原子荧光光谱测定土壤和水系沉积物中硒的干扰来源及消除方法

1.
河南省土壤重金属污染监测与修复重点实验室, 河南济源 459000

2.
中国环境监测总站, 北京 100012

基金项目:
国家环境保护公益性行业科研专项“重点防控重金属关键先进监测技术适用性研究项目”（201309050）

详细信息

作者简介: 赵宗生, 高级工程师, 主要从事环境监测工作。E-mail:envirend@aliyun.com

通讯作者: 张霖琳, 博士, 教授级高级工程师, 主要从事环境监测分析技术与方法研究。E-mail:zhangll@cnemc.cn

中图分类号: O657.31;O613.52

收稿日期: 2018-09-19

修回日期: 2019-03-14

录用日期: 2019-04-09

Interference Sources and Elimination Methods for the Determination of Selenium in Soil and Water Sediment by Atomic Fluorescence Spectrometry

1.
Henan Province Key Laboratory of Heavy-metal Pollution Monitoring and Remediation, Jiyuan 459000, China

2.
China National Environmental Monitoring Center, Beijing 100012, China

More Information

Corresponding author: Lin-lin ZHANG, zhangll@cnemc.cn

Received Date: 19 September 2018

Revised Date: 14 March 2019

Accepted Date: 09 April 2019

摘要

摘要: 原子荧光光谱法（AFS）具有灵敏度高、结构简单、容易操作等优点，但目前测定土壤和沉积物中的硒等元素的标准方法所采用的消解过程繁琐，易产生干扰。沸水浴可以把土壤和水系沉积物中硒提取完全，本文根据样品中元素丰度和仪器性能，将AFS测定Se的干扰分为Cu和Pb两大类，根据实验提出在水浴消解液加入浓盐酸（不宜加入硫脲-抗坏血酸），通过增加溶液酸度和Cl^-浓度，即保持样品中盐酸浓度高于23%，可抑制Cu²⁺还原为Cu⁰和Pb⁴⁺生成PbH₄，有效降低了Cu的负干扰和Pb的正干扰，提高了AFS测定Se的精密度和准确度。本方法测定Se的检出限为0.008mg/kg，测试标准物质的相对标准偏差为0.5%~11%，相对误差为-16.3%~9.5%；比行业标准HJ 680—2013的检出限（0.01mg/kg）、精密度（0.79%~23.1%）和准确度等技术指标更佳。
- 土壤 /
- 水系沉积物 /
- 水浴消解 /
- 硒 /
- 原子荧光光谱法 /
- 干扰消除
Abstract: BACKGROUNDAtomic Fluorescence Spectrometry (AFS) has advantages of high sensitivity, simple structure and easy operation, but the digestion process of the standard analysis method for determination of Se in soil is cumbersome and readily produces interference. OBJECTIVESTo evaluate the applicability of Se determination in soil and sediment by water bath digestion/AFS, and uncover the main interference and elimination methods. METHODSBased on the standard method of GB/T 22105-2008, boiling water bath of aqua regina was used to digest Se in soil and sediment. Four treatments, including Fe³⁺, concentrated hydrochloric acid, Fe³⁺with concentrated hydrochloric acid, and water bath solution, were used to eliminate the interference of Cu²⁺ and Pb⁴⁺. RESULTSThe detection limit of Se by this method was 0.008mg/kg, the relative standard deviation of the test reference materials was 0.5%-11%, and the relative error was -16.3%-9.5%, better than the detection limit (0.01mg/kg), precision (0.79%-23.1%) and accuracy of the industry standard HJ 680-2013. CONCLUSIONSAccording to the experiment, it is proposed to add concentrated hydrochloric acid to the water bath digestion solution without adding thiourea-ascorbic acid. By increasing the acidity and Cl^- concentration of the solution and keeping the concentration of hydrochloric acid in the sample higher than 23%, the reduction of Cu²⁺ to Cu⁰ and Pb⁴⁺ to form PbH₄ can be inhibited. The negative interference of Cu and the positive interference of Pb are effectively reduced, and the precision and accuracy of Se measured by AFS are improved.
- soil /
- sediment /
- water bath digestion /
- selenium /
- Atomic Fluorescence Spectrometry /
- interference elimination

HTML全文

表 1 标准物质中硒测定结果

Table 1. Determination results of selenium in certified reference materials of soils and sediments

标准物质编号	标准物质采样地区	Se认定值 (mg/kg)	Se含量6次测定平均值 (mg/kg)	RSD (%)	平均相对误差 (%)	ΔlgC(GBW)
GBW07406	广东阳春多金属矿区黄色红壤	1.34±0.17	1.440	4.3	7.5	0.031
GBW07430	珠江三角洲	0.51±0.05	0.477	2.4	-6.5	0.029
GBW07451	山东日照市黄海滩涂沉积物	0.11±0.02	0.093	11.0	-15.5	0.073
GBW07453	广东阳江市南海滩涂沉积物	0.20±0.03	0.174	6.4	-13.0	0.060
GBW07455	安徽五河淮河沉积物	0.14±0.02	0.129	4.6	-7.9	0.036
GBW07456	江苏张家港长江沉积物	0.29±0.04	0.285	6.6	-1.7	0.008
GBW07457	湖南益阳市湘江沉积物	0.44±0.05	0.459	0.5	4.4	0.018
GBW07307a	辽宁开源铅锌矿区	(0.26)	0.251	4.9	-3.5	0.015
GBW07311	湖南柿竹园多金属矿区	0.20±0.05	0.219	7.1	9.5	0.039
GBW07312	广东阳春多金属矿区	0.25±0.03	0.241	4.8	-3.6	0.016
GBW07362	青海拉水下铜镍矿区	0.24±0.02	0.201	3.8	-16.3	0.077

下载: 导出CSV

表 2 不同方式处理土壤及水系沉积物硒的测定结果

Table 2. Analytical results of selenium in soil and sediment pretreated with different methods

样品处理方式	Fe³⁺含量	盐酸浓度 (%)^③	GBW07453		GBW07311		GBW07312
样品处理方式	Fe³⁺含量	盐酸浓度 (%)^③	测定值 (mg/kg)	认定值 (mg/kg)	测定值 (mg/kg)	认定值 (mg/kg)	测定值 (mg/kg)	认定值 (mg/kg)
铁盐	0.83x%+1.17% (1.20%)	6.25	0.179 0.171 0.175	0.20±0.03	0.502 0.463 0.448	0.20±0.05	0.324 0.310 0.330	0.25±0.03
上清液	x%^①(0.04%)^②	7.50	0.162 0.163 0.172	0.20±0.03	0.341 0.331 0.340	0.20±0.05	0.178 0.185 0.176	0.25±0.03
盐酸-铁盐	0.86x%+1.00% (1.03%)	19.6	0.170 0.164 0.166	0.20±0.03	0.328 0.339 0.339	0.20±0.05	0.288 0.298 0.300	0.25±0.03
盐酸	0.83x%(0.03%)	22.9	0.165 0.161 0.168	0.20±0.03	0.230 0.232 0.229	0.20±0.05	0.245 0.253 0.254	0.25±0.03
注：①x%为样品中溶出的Fe³⁺含量，②括号内取值为所有土壤及水系沉积物中Fe₂O₃中位数5.00%折算后Fe³⁺含量，③未考虑消解过程盐酸损失。

下载: 导出CSV

表 3 硫脲-抗坏血酸和浓盐酸处理方式对硒测试的影响

Table 3. Effects of treatment with thiourea-ascorbic acid and hydrochloric acid on selenium in soil sample

样品类型	标准物质编号	标准物质采样地区	Se认定值 (mg/kg)	浓盐酸处理		硫脲-抗坏血酸处理
样品类型	标准物质编号	标准物质采样地区	Se认定值 (mg/kg)	Se测定值 (mg/kg)	回收率 (%)	Se测定值 (mg/kg)	回收率 (%)
	GBW07402	内蒙四子王旗和白云鄂博栗钙土	0.16±0.03	0.131	82.0	0.034	21.4
	GBW07408	陕西洛川黄土	0.10±0.01	0.083	80.0	0.013	13.0
土壤	GBW07423	洪泽湖沉积物	0.15±0.03	0.131	87.5	0.012	8.00
	GBW07430	珠江三角洲	0.51±0.05	0.454	88.9	0.049	9.61
	GBW07456	江苏张家港长江沉积物	0.29±0.03	0.276	95.1	0.059	20.4
	GBW07386	江西省南昌市扬子洲	0.30±0.01	0.268	89.4	0.036	12.0
	GBW07312	广东阳春多金属矿区	0.25±0.03	0.273	109	0.101	40.2
	GBW07318	四川西昌多种火成岩和沉积岩分布区	(0.15)	0.178	119	0.085	56.5
水系沉积物	GBW07364	新疆吐鲁番小热泉子铜矿区	1.55±0.34	1.54	99.2	0.277	17.9
	GBW07366	江西德兴银山多金属矿区	0.69±0.08	0.704	102	0.113	16.3
	GBW07383	湖南汝城花岗岩区	0.652±0.066	0.618	94.8	0.100	15.3
	GBW07384	江西资溪花岗岩区	0.261±0.028	0.223	85.3	0.047	17.9

下载: 导出CSV

参考文献(30)

[1]	吕莉, 李源, 井美娇, 等.氢化物发生-原子荧光光谱法测定三种鸡蛋中硒含量的研究[J].光谱学与光谱分析, 2019, 39(2):607-611. http://d.old.wanfangdata.com.cn/Periodical/gpxygpfx201902044 Lü L, Li Y, Jing M J, et al.Determination of selenium in three kinds of eggs by hydride generation atomic fluorescence spectrometry[J].Spectroscopy and Spctral Analysis, 2019, 39(2):607-611. http://d.old.wanfangdata.com.cn/Periodical/gpxygpfx201902044
[2]	李杰, 刘久臣, 汤奇峰, 等.川西高原地区水体中硒含量及分布特征研究[J].岩矿测试, 2018, 37(2):183-192. http://www.ykcs.ac.cn/article/doi/10.15898/j.cnki.11-2131/td.201709250154 Li J, Liu J C, Tang Q F, et al.Study of the contents and distribution of selenium in water samples from the Western Sichuan plateau and the incidence of Kaschin Beck disease[J].Rock and Mineral Analysis, 2018, 37(2):183-192. http://www.ykcs.ac.cn/article/doi/10.15898/j.cnki.11-2131/td.201709250154
[3]	李刚, 胡斯宪, 陈琳玲.原子荧光光谱分析技术的创新与发展[J].岩矿测试, 2013, 32(3):358-376. doi: 10.3969/j.issn.0254-5357.2013.03.003 Li G, Hu S X, Chen L L.Innovation and development for AFS analysis[J].Rock and Mineral Analysis, 2013, 32(3):358-376. doi: 10.3969/j.issn.0254-5357.2013.03.003
[4]	钱薇, 唐昊冶, 王如海, 等.一次消解土壤样品测定汞、砷和硒[J].分析化学, 2017, 45(8):1215-1221. http://d.old.wanfangdata.com.cn/Periodical/fxhx201708020 Qian W, Tang H Y, Wang R H, et al.Determination of mercury, arsenic and selenium in soils by one-time digestion[J].Chinese Journal of Analytical Chemistry, 2017, 45(8):1215-1221. http://d.old.wanfangdata.com.cn/Periodical/fxhx201708020
[5]	李自强, 胡斯宪, 李小英, 等.水浴浸提-氢化物发生-原子荧光光谱法同时测定土壤污染普查样品中砷和汞[J].理化检验(化学分册), 2018, 54(4):480-483. http://d.old.wanfangdata.com.cn/Periodical/lhjy-hx201804022 Li Z Q, Hu S X, Li X Y, et al.Determination of As and Hg in survey samples of soil pollution by HG-AFS with water bath extraction[J].Physical Testing and Chemical Analysis (Part B:Chemical Analysis), 2018, 54(4):480-483. http://d.old.wanfangdata.com.cn/Periodical/lhjy-hx201804022
[6]	杨常青, 张双双, 吴楠, 等.微波消解-氢化物发生原子荧光光谱法和质谱法测定高有机质无烟煤中汞砷的可行性研究[J].岩矿测试, 2016, 35(5):481-487. http://www.ykcs.ac.cn/article/doi/10.15898/j.cnki.11-2131/td.2016.05.006 Yang C Q, Zhang S S, Wu N, et al.Feasibility study on content determination of mercury and arsenic in high organic anthracite by microwave digestion-HGAFS[J].Rock and Mineral Analysis, 2016, 35(5):481-487. http://www.ykcs.ac.cn/article/doi/10.15898/j.cnki.11-2131/td.2016.05.006
[7]	刘阁, 李清昌.氢化物原子荧光法同时测定土壤样品中砷锑[J].有色矿冶, 2013, 29(5):62-64. doi: 10.3969/j.issn.1007-967X.2013.05.019 Liu G, Li Q C.HG-AFS determination of arsenic and antimony in soil[J].Non-Ferrous Mining and Metallurgy, 2013, 29(5):62-64. doi: 10.3969/j.issn.1007-967X.2013.05.019
[8]	徐国栋, 葛建华, 贾慧娴, 等.水浴浸提-氢化物发生-原子荧光光谱法同时测定地质样品中痕量砷和汞[J].岩矿测试, 2010, 29(4):391-394. doi: 10.3969/j.issn.0254-5357.2010.04.014 http://www.ykcs.ac.cn/article/id/ykcs_20100414 Xu G D, Ge J H, Jia H X, et al.Simultaneous determination of trace arsenic and mercury in geological samples by HG-AFS with water bath soaking sample preparation[J].Rock and Mineral Analysis, 2010, 29(4):391-394. doi: 10.3969/j.issn.0254-5357.2010.04.014 http://www.ykcs.ac.cn/article/id/ykcs_20100414
[9]	赵振平, 张怀成, 冷家峰, 等.王水消解蒸气发生-原子荧光光谱法测定土壤中的砷、锑和汞[J].中国环境监测, 2004, 20(1):44-46. doi: 10.3969/j.issn.1002-6002.2004.01.014 Zhao Z P, Zhang H C, Leng J F, et al.The method of VG-AFS with clearing by aqua regia to determine As, Sb and Hg in the soil[J].Environmental Monitoring of China, 2004, 20(1):44-46. doi: 10.3969/j.issn.1002-6002.2004.01.014
[10]	李彩虹, 杨春霞, 赵银宝.氢化物发生-原子荧光法测定土壤中砷、汞的方法[J].西北农业学报, 2013, 22(7):200-204. http://d.old.wanfangdata.com.cn/Periodical/xbnyxb201307034 Li C H, Yang C X, Zhao Y B.Determination of As and Hg in soil by HG-AFS[J].Acta Agriculturae Boreali-Occidentalis Sinica, 2013, 22(7):200-204. http://d.old.wanfangdata.com.cn/Periodical/xbnyxb201307034
[11]	李艳, 程永毅, 陈可雅, 等.王水加辅助酸微波消解-原子荧光法测定土壤砷、硒[J].西南大学学报(自然科学版), 2016, 38(11):155-160. http://www.cnki.com.cn/Article/CJFDTotal-XNND201611024.htm Li Y, Cheng Y Y, Chen K Y, et al.Determination of soil arsenic and selenium by atomic fluorescence under microwave digestion with aqua regia plus assisted acid[J].Journal of Southwest University(Natural Science Edition), 2016, 38(11):155-160. http://www.cnki.com.cn/Article/CJFDTotal-XNND201611024.htm
[12]	苏文峰, 李刚.焙烧分离-氢化物发生-原子荧光光谱法测定土壤样品中微量硒[J].岩矿测试, 2008, 27(2):120-122. doi: 10.3969/j.issn.0254-5357.2008.02.010 http://www.ykcs.ac.cn/article/id/ykcs_20080243 Su W F, Li G.Determination of trace selenium in soil samples by HG-AFS with baking separation[J].Rock and Mineral Analysis, 2008, 27(2):120-122. doi: 10.3969/j.issn.0254-5357.2008.02.010 http://www.ykcs.ac.cn/article/id/ykcs_20080243
[13]	张锦茂, 范凡, 任萍.氢化物-原子荧光法测定岩石中痕量硒的干扰及消除[J].岩矿测试, 1993, 12(4):264-267. http://www.ykcs.ac.cn/article/id/ykcs_199304107 Zhang J M, Fan F, Ren P.Elimination of interference in the determination of selenium in rocks by HG-AFS[J].Rock and Mineral Analysis, 1993, 12(4):264-267. http://www.ykcs.ac.cn/article/id/ykcs_199304107
[14]	徐宝玲.氢化物-原子荧光法测定硒时元素的干扰及其消除[J].分析化学, 1985, 13(1):29-33. http://www.cnki.com.cn/Article/CJFDTotal-FXHX198501006.htm Xu B L.Interference of elements and its elimination in HG-AFS determination of selenium[J].Chinese Journal of Analytical Chemistry, 1985, 13(1):29-33. http://www.cnki.com.cn/Article/CJFDTotal-FXHX198501006.htm
[15]	王丹君.原子荧光光谱法测定土壤中的硒[J].理化检验(化学分册), 2014, 50(7):914-915. http://d.old.wanfangdata.com.cn/Periodical/lhjy-hx201407034 Wang D J.Determination of selenium in soil with AFS[J].Physical Testing and Chemical Analysis (Part B:Chemical Analysis), 2014, 50(7):914-915. http://d.old.wanfangdata.com.cn/Periodical/lhjy-hx201407034
[16]	陈志兵.碱性模式氢化物发生-原子荧光光谱法测定土壤中的痕量硒[J].岩矿测试, 2002, 21(4):311-314. doi: 10.3969/j.issn.0254-5357.2002.04.015 http://www.ykcs.ac.cn/article/id/ykcs_20020481 Chen Z B.Determination of trace selenium in soils by HG-AFS in alkaline mode[J].Rock and Mineral Analysis, 2002, 21(4):311-314. doi: 10.3969/j.issn.0254-5357.2002.04.015 http://www.ykcs.ac.cn/article/id/ykcs_20020481
[17]	邵建辉.原子荧光法测定土壤中痕量硒元素[J].现代化工, 2015, 35(5):177-178. http://www.cnki.com.cn/Article/CJFDTotal-XDHG201505046.htm Shao J H.Determination of trace selenium in soil by AFS[J].Modern Chemical Industry, 2015, 35(5):177-178. http://www.cnki.com.cn/Article/CJFDTotal-XDHG201505046.htm
[18]	陶秋丽, 韩张雄, 熊英, 等.微波消解-氢化物发生原子荧光光谱法测定粉煤灰中的硒[J].岩矿测试, 2013, 32(3):445-448. doi: 10.3969/j.issn.0254-5357.2013.03.016 http://www.ykcs.ac.cn/article/id/faa2bfa4-6964-4bde-9824-ff793360c12a Tao Q L, Han Z X, Xiong Y, et al.Determination of selenium in coal ash with microwave digestion and HG-AFS[J].Rock and Mineral Analysis, 2013, 32(3):445-448. doi: 10.3969/j.issn.0254-5357.2013.03.016 http://www.ykcs.ac.cn/article/id/faa2bfa4-6964-4bde-9824-ff793360c12a
[19]	郭小伟, 张文琴, 杨密云.氢化物-无色散原子荧光法测定地质样品中微量硒及碲[J].岩石矿物及测试, 1983, 2(4):288-292. http://www.cnki.com.cn/Article/CJFDTotal-YSKW198304006.htm Guo X W, Zhang W Q, Yang M Y.Determination of trace amount of selenium and tellurium in geological samples by HG-AFS[J].Acta Petrologica Mineralogica et Analytica, 1983, 2(4):288-292. http://www.cnki.com.cn/Article/CJFDTotal-YSKW198304006.htm
[20]	薛超群, 郭敏.氢化物发生-原子荧光光谱法测定土壤样品中不同价态的硒[J].岩矿测试, 2012, 31(6):980-984. doi: 10.3969/j.issn.0254-5357.2012.06.012 http://www.ykcs.ac.cn/article/id/ykcs_20120613 Xue C Q, Guo M.Analysis of different valence states of selenium in geological samples by HG-AFS[J].Rock and Mineral Analysis, 2012, 31(6):980-984. doi: 10.3969/j.issn.0254-5357.2012.06.012 http://www.ykcs.ac.cn/article/id/ykcs_20120613
[21]	张洁, 阳国运.树脂交换分离-电感耦合等离子体质谱法测定铅锌矿中钨钼锡锗硒碲[J].岩矿测试, 2018, 37(6):657-663. http://www.ykcs.ac.cn/article/doi/10.15898/j.cnki.11-2131/td.201803250028 Zhang J, Yang G Y.Determination of tungsten, molybdenum, tin, germanium, selenium and tellurium in lead-zinc ore by ICP-MS with resin exchange separation[J].Rock and Mineral Analysis, 2018, 37(6):657-663. http://www.ykcs.ac.cn/article/doi/10.15898/j.cnki.11-2131/td.201803250028
[22]	莫永涛, 王琦, 谢意南, 等.水浴消解-原子荧光法同时测定沉积物中锑与硒[J].广东化工, 2015, 42(7):167-169. doi: 10.3969/j.issn.1007-1865.2015.07.083 Mo Y T, Wang Q, Xie Y N, et al.Simultaneous determination of antimony and selenium in the sediment by nitromurlatic acid water bath diggestion-AFS[J].Guangdong Chemical Industry, 2015, 42(7):167-169. doi: 10.3969/j.issn.1007-1865.2015.07.083
[23]	刘明钟, 汤志勇, 刘霁欣, 等.原子荧光光谱分析[M].北京:化学工业出版社, 2007:229-233. Liu M Z, Tang Z Y, Liu J X, et al.Analysis by AFS[M].Beijing:Chemical Industry Press, 2007:229-233.
[24]	张立新, 陈志勇, 周新青.氢化物发生原子荧光法在测定土壤中浸出硒、总硒的应用[J].中国环境监测, 2006, 22(2):29-31. doi: 10.3969/j.issn.1002-6002.2006.02.009 Zhang L X, Chen Z Y, Zhou X Q.Determination of trace selenium in soil by HG-AFS[J].Environmental Monitoring of China, 2006, 22(2):29-31. doi: 10.3969/j.issn.1002-6002.2006.02.009
[25]	陶琛, 李春生, 初威澄, 等.非色散原子荧光光谱法同时检测硒和铅的光源干扰校正方法研究[J].分析化学, 2019, 47(1):163-168. http://d.old.wanfangdata.com.cn/Periodical/fxhx201901021 Tao C, Li C S, Chu W C, et al.Correction method of light source interference for simultaneous determination of selenium and lead by non-dispersive hydride generation-atomic fluorescence spectrometry[J].Chinese Journal of Analytical Chemistry, 2019, 47(1):163-168. http://d.old.wanfangdata.com.cn/Periodical/fxhx201901021
[26]	陈曦, 赵伯燕, 陈艳梅, 等.不同介质对氢化物发生原子荧光光谱法测定硒的影响[J].微量元素与健康研究, 2012, 29(5):2. http://d.old.wanfangdata.com.cn/Periodical/wlysyjkyj201205034 Chen X, Zhao B Y, Chen Y M, et al.Effect of different media on determination of selenium by HG-AFS[J].Studies of Trace Elements and Health, 2012, 29(5):2. http://d.old.wanfangdata.com.cn/Periodical/wlysyjkyj201205034
[27]	戴亚明.铅的氢化物发生机理研究及钢铁中痕量铅的测定[J].理化检验(化学分册), 2005, 41(10):712-717. Dai Y M.HG-AFS determination of trace amounts of lead in iron and steel[J].Physical Testing and Chemical Analysis (Part B:Chemical Analysis), 2005, 41(10):712-717.
[28]	李俊义, 徐书绅, 张渔夫, 等.分析化学[M].北京:高等教育出版社, 1984:602-605, 629-646. Li J Y, Xu S S, Zhang Y F, et al.Analytical Chemistry[M].Beijing:Higher Education Press, 1984:602-605, 629-646.
[29]	李倩, 张宝, 申文前, 等.硒酸泥制备粗硒新工艺[J].中南大学学报(自然科学版), 2011, 42(8):2209-2214. http://d.old.wanfangdata.com.cn/Periodical/zngydxxb201108008 Li Q, Zhang B, Shen W Q, et al.Novel technology for preparation of crude Se from selenium acid mud[J].Journal of Central South University (Science and Technology), 2011, 42(8):2209-2214. http://d.old.wanfangdata.com.cn/Periodical/zngydxxb201108008
[30]	李小芳, 冯小强, 章志典, 等.羧甲基壳聚糖软模板法制备纳米硒[J].材料科学与工程学报, 2013, 31(6):886-890. doi: 10.3969/j.issn.1673-2812.2013.06.023 Li X F, Feng X Q, Zhang Z D, et al.Preparation of nano-selenium using carboxymethyl chitosan as template[J].Journal of Materials Science and Engineering, 2013, 31(6):886-890. doi: 10.3969/j.issn.1673-2812.2013.06.023