大体积进样离子色谱法测定环境水样中高氯酸根

采用大体积500μL进样离子色谱法,电导检测测定了几种水体中高氯酸盐的含量。分析柱为容量高、亲水性强的以脂肪族碳骨架为基质的阴离子交换柱IonPac AS20,淋洗液在线发生器自动产生35 mmol/LKOH淋洗液,0.25 mL/m in等浓度淋洗。这种新型的以脂肪族碳骨架为基质的阴离子交换柱的采用,极大的削弱了该色谱柱对对氯苯磺酸的保留,完全消除了现行美国EPA高氯酸盐分析方法中高氯酸根与对氯苯磺酸共淋洗的问题。方法对高氯酸根的检出限(S/N=3)为0.5μg/L,高氯酸根浓度在1~1000μg/L范围内具有良好的线性(r=0.9991)。将本方法应用于自来水、河水和雪水样品中高氯酸盐的检测,实际样品的加标回收率在87%~114%之间;1μg/L高氯酸根连续进样9次,色谱峰面积相对标准偏差(RSD)为6.9%。     

二维离子色谱法同时测定环境水样中的碘离子、硫氰酸根和高氯酸根

建立了二维离子色谱法同时测定环境水样中的碘离子、硫氰酸根离子和高氯酸根离子的方法。先采用常规阴离子色谱柱(IonPac AS16, 250 mm×4 mm)将水样中的碘离子、硫氰酸根离子和高氯酸根离子与干扰离子进行分离。样品溶液通过抑制器后,将含有碘离子、硫氰酸根离子和高氯酸根离子的淋洗液导入富集柱(MAC-200, 80 mm×0.75 mm),再通过毛细管阴离子色谱柱(IonPac AS20 Capillary, 250 mm×0.4 mm)进行分离和定量分析。方法的线性范围为0.05～100 μg/L,相关系数达到0.9999,检出限为0.02～0.05 μg/L。样品中碘离子、硫氰酸根离子和高氯酸根离子的加标回收率在85.1%～100.1%之间,回收率的相对标准偏差(RSD)(n=6)在1.7%～4.9%之间。该法试剂用量小,灵敏度比常规离子色谱提高30～40倍,同时去除了样液中的高浓度基体杂质,适用于水样中低含量碘离子、硫氰酸根离子和高氯酸根离子的检测。     

阳离子交换树脂分离-铝试剂分光光度法测定土壤中铝形态

研究了铝试剂光度法测定土壤溶液中铝的最佳条件,着重探讨了共存离子,特别是土壤溶液中的无机离子和有机阴离子对测定铝的影响。采用阳离子交换树脂分离,建立了测定土壤溶液及天然水中铝形态方法。用该法可测定总反应性铝、总单核铝和稳定性单核铝。由总反应性铝减去总单核铝求得酸溶性铝。由总单核铝减去稳定单核铝求得不稳定单核铝。与阳离子树脂交换分离-邻苯二酚紫光度法进行了比较。结果表明：邻苯二酚紫光度法灵敏度较高,但铁的干扰较大。铝试剂光度法灵敏度略低,但铁的干扰较少。阳离子树脂交换分离-铝试剂光度法更适合于测定含铁量比较高的土壤溶液中的铝形态。     

离子色谱法测定高锰酸钾中以及高浓度硝酸根中的高氯酸根

地下水和地表水中的高氯酸根危害人体健康。由于环境水样中的高浓度硝酸根和高锰酸钾基体干扰高氯酸根的测定,本方法通过滴加一定量的过氧化氢以除去高锰酸根,然后对样品进行离心来消除干扰。运用Dionex IonPac AS11型阴离子分离柱,流动相为8mmol/LKOH溶液,大体积(200μL)进样,抑制性电导检测器来测定有高锰酸钾以及高浓度硝酸根干扰的水中痕量高氯酸根。本方法的线性范围0.5~20mg/L,检出限为5μg/L。     

D290大孔阴离子交换树脂对W（Ⅵ）、Mo（Ⅵ）吸附性能的研究

本文研究了D290大孔阴离子交换树脂吸附W（Ⅵ）、Mo（Ⅵ）时，酸度、浓度、温度、流速等对吸附量的影响。确证了该种树脂对W（Ⅵ）、Mo（Ⅵ）的偏酸根吸附量大于其正酸根的吸附量，但交换速度慢于后者的交换速度。并研究了在上述诸条件下，D290树脂从溶液中分离钨、钼的方法。     

氢化物发生-原子荧光法测定纯铜中镉

用717阴离子交换树脂填充柱选择性吸附CdCl42-阴离子,以实现其与大量铜基体的分离。在标准溶液中匹配适当基体浓度并采用氢化物发生-原子荧光法,实现了铜/镉质量比为2000~50000的纯铜中痕量镉的测定。在基体铜的浓度为50mg/L的样品消化液中,镉的检出限为0.2μg/L;精密度为3.0%(n=7,3.0μg/L),镉浓度在1.0~25.0μg/L范围内呈良好线性关系。本法适用于纯铜中痕量镉的测定。     

离子交换剂在物质的分离、提纯、精制和回收中的应用文摘

标题的过程包括将H_2O_2与含有一种被吸附的螯合剂的阴离子交换树脂接触。这一方法可用于去除金属离子。高纯H_2O_2尤其适用于Si晶片的清洗剂。例如,用250mL0.3N的Na_4EDTA溶液处理50ml氯型Amberlite IRA-900(带季铵盐阴离子的苯乙烯—二乙烯苯共聚物)阴离子交换树脂,在2小时内     

阴离子树脂苯取富集-分光光度法测定煤矸石中痕量钪

研究了对乙酰基偶氮氯膦(CPApA)与钪(Ⅲ)的显色反应,在HNO3介质中,在Triton X-100存在下,CPApA与钪(Ⅲ)反应生成摩尔比为1:1的稳定配合物,该配合物可用717型阴离子树脂交换柱萃取富集,再通过树脂相光度法测定钪,由此建立了测定钪的新方法.吸附配合物树脂相的最大吸收波长为690 nm,表观摩尔吸光系数为9.56×105 L·mol-1·cm-1.钪的质量浓度在0～480μg/L范围内符合比耳定律.经阴离子树脂交换柱萃取富集后,钪的测定灵敏度可提高数倍,大多数常见离子不干扰测定.方法应用于煤矸石痕量钪的测定,结果满意.样品分析结果的相对标准偏差小于5%,加标回收率为96.0%～102.5%.     

阴离子交换固相萃取-气相色谱/质谱法分析人血浆中6种神经性毒剂降解产物

采用醋酸汞去除蛋白,实现了阴离子交换固相萃取-气相色谱/质谱法同时测定人血浆中6种神经性毒剂降解产物的三甲基硅烷衍生物。考察了不同溶剂的去蛋白效率和不同固相萃取柱对毒剂降解产物的保留行为,优化了阴离子交换树脂的洗脱条件。采用选择离子监测方式,6种降解产物在0.05~5.0 mg/L范围内呈良好的线性关系,最低检出限在22μg/L以内;RSD均小于9.7%。该方法检测灵敏度高,血浆样品干扰小,是一种理想的血浆中神经性毒剂降解产物的检测方法。     

阴离子树脂萃取富集-分光光度法测定煤矸石中痕量钪

研究了对乙酰基偶氮氯膦(CPApA)与钪(Ⅲ)的显色反应,在HNO3介质中,在TritonX-100存在下,CPApA与钪(Ⅲ)反应生成摩尔比为1:1的稳定配合物,该配合物可用717型阴离子树脂交换柱萃取富集,再通过树脂相光度法测定钪,由此建立了测定钪的新方法。吸附配合物树脂相的最大吸收波长为690nm,表观摩尔吸光系数为9.56×105L.mol-1.cm-1。钪的质量浓度在0～480μg/L范围内符合比耳定律。经阴离子树脂交换柱萃取富集后,钪的测定灵敏度可提高数倍,大多数常见离子不干扰测定。方法应用于煤矸石痕量钪的测定,结果满意。样品分析结果的相对标准偏差小于5%,加标回收率为96.0%～102.5%。     

Characterization of aluminum species with nitrate, perchlorate and sulfate ions in the positive and negative ion mode by electrospray ionization mass spectrometry

The application of electrospray ionization mass spectrometry (ESI-MS) for aluminum speciation in the positive and negative ion modes was discussed. Aluminum nitrate, perchlorate and sulfate solutions were measured by ESI-MS. In the positive ion mode, aluminum species containing anions (Al-L; L=NO3, ClO4 and SO4) were identified, while [Al(OH)2(H2O)n]+ (n=2-4) were the main species. The affinity of the anions with Al3+ estimated by ESI-MS was consistent with the hardness of the anions (hard and soft acids and bases principle) and the results from 27Al nuclear magnetic resonance studies. This indicates that the results observed from the positive ion mode preserved the chemical state of aluminum in the solution. In the negative ion mode, [Al(OH)4-nLn]- (n=0-2, L=NO3, ClO4) were the main species, which were considered to be converted from positive aluminum species, [Al(OH)(H2O)n]+ (n=2-4), by the successive addition of anions. Anions did not only attach to one aluminum ion but also bridged two aluminum ions. In Al2(SO4)3 solution, the behavior of SO4(2-) in the negative ion mode differed from that of NO3- and ClO4-. This may reflect the affinity of SO4(2-) with Al3+ in the solution or in the mass spectrometer or in both. Finally, detection mechanisms for the aluminum species in the solution are proposed for both the positive and negative ion modes. It is shown that ESI-MS can be used to observe the interaction between Al3+ and anions. We show the importance of the interpretation of the results by ESI-MS for obtaining new information of the metal species in the solution.     

聚(3-甲基噻吩)的电化学稳定性及电催化行为

用连续循环伏安法研究了电化学法制备的聚(3-甲基噻吩)(PMT)薄膜修饰玻璃碳电极在不同支持电解质溶液中的电化学稳定性。在易嵌入PMT的阴离子存在下, PMT电活性随扫描次数按表现二级反应降低; 在难嵌入PMT的离子存在下, PMT具有良好稳定性; 在含有氯、溴离子的水溶液中, PMT可将卤离子电催化氧化, 并引起PMT电活性迅速下降。光电子能谱分析表明氯已键合到PMT结构上。     

Photoluminescent metal-sulfur clusters derived from tetrathiometalates: metal-to-metal charge-transfer excited states of d0-d10 heterobimetallic sulfido clusters with bulky phosphine ligands

Reactions of MS4(2-) (M = Mo, W) with M'(PCy3)X (M'=Ag/Au, X= ClO4/Cl) and [Cu2(dcpm)2(MeCN)2](ClO4)2 (dcpm = bis(dicyclohexylphosphino)methane) afforded heterometallic sulfido clusters [M'2(PCy3)2(MS4)] (M=Mo, M'=Au: 2; M=W, M'=Ag: 3, Au: 4) and [Cu4(dcpm)4(MS4)](ClO4)2 (M=Mo: 5 x (ClO4)2, W: 6 x (ClO4)2), all of which, except 4, have been characterized by X-ray structure determination. Clusters 5 x(ClO4)2 and 6 x (ClO4)2 feature unusual 16-membered [Cu4P5C4] metallamacrocycles formed on the respective tetrathiometalate anion templates and have unusually long Cu-S bonds and Cu...M distances for metal sulfur clusters that contain a saddle-shaped [Cu4MS4] core. Low-energy absorption bands are observed in their electronic spectra at approximately 562 and 467 nm, respectively, assignable to MMCT transitions; quasireversible reduction waves are observed with E(1/2) = -1.43 (52+) and -1.78 V (62+) versus FeCp2(0/+); and they are emissive either in the solid state or in solution. The emission of 6(2+) can be quenched by both electron acceptors, such as methylviologen, or electron donors, such as aromatic amines, with the excited state reduction potential E(62+*/6+) estimated to be approximately 1.13V versus a normal hydrogen electrode.     

微波消解-原子吸收法测定氧化铝为载体的钯催化剂中钯

报道了微波消解-AAS法测定氧化铝为载体的钯催化剂中钯的新方法,试验了微波消解溶样条件（溶解试剂、压力、时间和功率等）,研究了测定介质的影响,通过在样品测定液中加入铝基体至铝浓度为4 mg/mL,消除了铝对钯测定的干扰.该法测定结果与光度法的结果一致,相对标准偏差小于1.5%（n=5）.     

ICP-AES 法间接测定高氯酸二乙基联吡啶中的高氯酸根

研究了ICP－AES法间接测定高氯酸二乙基联吡啶中高氯酸根含量的方法,选择了氯化四苯Lin（TPPCl）与高氯酸根发生沉淀的条件及ICP－AES测定四苯Lin的最佳条件,在氯化四苯Lin过量的情况下,在水中难溶的高氯酸二乙基联吡啶可以定量转化成TPPClO4晶形沉淀,通过测定反应剩余的TPPCl,可计算得到样品中高氯酸根的含量,方法的相对标准偏差0.74%,回收率99.5%-100.6%。同时以TPPCl为沉淀剂,用重量法测定了样品中高氯酸根含量,结果与ICP－AES法一致。     

Electrothermal volatilization of aluminum as 1-phenyl-3-methyl-4-benzoylpyrazolone[5] chelate for gaseous sample introduction in ICP-AES

Based on gaseous compound introduction as 1-phenyl-3-methyl-4-benzoylpyrazolone[5](PMBP) chelate of aluminum by electrothermal vaporization in ICP-AES, a method for determination of trace aluminum was developed. Trace aluminum was vaporized at temperature of 1000 degrees C, and the vaporization behavior of aluminum chelate was detailedly investigated. Under the optimum conditions, the detection limit of aluminum was 0.6 ng ml(-1), and the relative standard deviation for 0.1 mug ml(-1) aluminum was 4.7% (n=8). The proposed method was applied to the determination of trace aluminum in rice flour reference materials, and the results well agreed with the reference values.     

空气—乙炔焰中高氯酸镧对锶的增感效应及其分析应用

本文试验了稀土元素对空气－乙炔火焰原子吸收测定锶的影响，并且选择镧作了重点研究，发现不同镧盐对测定锶的影响各不相同，当存在每ｍＬ１５００μｇ镧（高氯酸盐）时，硝酸浓度在比较宽的范围内不影响锶的测定，本文建立建立了Ｓｒ－Ｌａ（ＣｌＯ４）３－ＨＮＯ３体系中测量锶的新方法，该方法用于人工混合稀土样品中Ｓｒ的测定，获得满意的结果。     

The use of chlorophenol red for the selective determination of chlorine dioxide in drinking water

In recent years, the use of chlorine dioxide as an alternative disinfectant for drinking water has become increasingly attractive. As a result, an accurate method for the determination of mg l(-1) concentrations of chlorine dioxide is needed. Improvements to chlorophenol red (CPR) spectrophotometry result in a selective method for ClO(2) with few interferences. CPR selectively reacts with 0.1-1.9 mg l(-1) ClO(2) at pH 7, yielding a linear response (0.9994) with a limit of detection of 0.12 mg l(-1) ClO(2). Several species, ClO(2)(-), ClO(3)(-), NH(2)Cl, and free available chlorine (FAC), were studied as potential interferents using this method. There was found to be less than 2% interference due to 1.38 mg l(-1) ClO(2)(-), 9.87 mg l(-1) ClO(3)(-1), and 5.31 mg l(-1) NH(2)Cl. The interference from up to 1.19 mg l(-1) FAC was 3.7% and could be further reduced by the addition of oxalic acid, sodium cyclamate or thioacetamide.     

Catalytic resonance scattering spectral method for the determination of trace amounts of Se

A new catalytic kinetic method has been proposed for the determination of Se from 8.0x10(-9) to 8.0x10(-8) M, using the fact that Se(IV) can catalyze the slow reaction between KClO(3) and phenylhydrazine sulfate (PH) in 0.1 M H(2)SO(4) solution at 100 degrees C. The reduction product of ClO(3)(-), Cl(-), reacts with Ag(+) to form (AgCl)(n) nanoparticles. The nanoparticles exhibit a maximum resonance scattering spectral peak at 470 nm. The intensity of resonance scattering light at 470 nm is linear with respect to the Se concentration, using the fixed-reaction time procedure. The factors influencing the determination of Se were examined. This catalytic resonance scattering spectral method has been applied to the analysis of Se in real samples, with satisfactory results.