微肥中锌的双硫腙螯合微粒共振散射光谱分析

在pH9．0的NH3—NH3-Cl缓冲溶液中,Zn(Ⅱ)与双硫腙可形成能稳定存在的螯合物微粒,显示出共振散射效应．该微粒体系的最强共振散射峰在605nm处,锌的浓度在0．02～1．54μg／mL范围内与共振散射强度(J605nm)呈线性关系,检出限为0．008μg／mL Zn．利用共振散射测量微肥中微量元素锌,方法简单、灵敏度高、重现性好,结果满意。     

国标GB5750-85双硫腙分光光度法测定镉——对水样预处理方法的探讨

对双硫腺分光光度法测定Cd时,水样处理方法进行了探讨,针对某些污染严重的水样,采用浓硝酸－过氧化氢前处理水样,并在有Na3PO4存在的情况下,于600℃的高温炉中灰化,结果令人满意。     

示波极谱法直接测定锌电解液中钴的研究

研究了pH5 0的HAc -NaAc介质中 ,存在大量锌时 ,钴 -丁二酮肟 -柠檬酸钠 -氯化铵体系灵敏的配合物吸附波。峰电位 -0 .93V ,在0 0001～0 .1mg/L范围内钴质量浓度与峰电流呈线性关系 ,检出限达8 5×10-10mol/L。方法无须预处理可直接测定电解锌料液中微量钴。对电活性配合物的组成、极谱波性质和电极过程机理也作了研究     

Solvent Sublation Using Dithizone as a Ligand for Determination of Trace Elements in Water Samples

Solvent sublation was studied as a method of separating and pre-concentrating traces of Zn(II), Cd(II) and Cu(II) as diphenylthiocarbazone (dithizone) complexes for their determination. The experimental conditions, such as pH of solution, amount of dithizone as ligand, stirring time, gas flow rate and flotation time, were optimized. Different non-ionic surfactants and types of organic solvents were optimized for efficient sublation. The analyte ions in a 350mL sample were complexed as metal-dithizone complexes by adding 10mL of 0.084% dithizone, 0.5mL of 0.1% nonylphenol polyoxyethylene ether (NP) and 10mL of pH 4.3 potassium hydrogen phthalate-sodium hydroxide buffer solution. The solution was stirred with a mechanical stirrer for 30min. It was transferred to a flotation cell, and the complexes were floated by bubbling air and extracted into 10mL of methylisobutyl ketone (MIBK) on the surface of the aqueous solution. The analytes in the organic phase were determined by flame atomic absorption spectrometry (F-AAS) for Zn(II) and by graphite furnace atomic absorption spectrometry (GF-AAS) for Cd(II) and Cu(II). The proposed method was applied to determine Zn(II), Cd(II) and Cu(II) in real water samples; the enrichment factor was more than 37, the RSD was less than 4.26%, recoveries ranged from 92.7 to 107.3%, and the detection limits were 1.0µgL^–1 for Zn(II), 0.006µgL^–1 for Cd(II) and 0.06µgL^–1 for Cu(II). The results obtained were satisfactory.     

胶束增溶光度法同时测定铂、铑、钯和金的研究

本文研究了贵金属Pt、Rh、Pd和Au在SnCl_2-BRB-AG-乳化剂OP离子缔合物体系中显色反应的条件,采用偏最小二乘回归法对上述体系重迭光谱进行解析及数据处理。结果表明,该体系灵敏度高,表观摩尔吸光系数可达1.74×10～6～2.47×10～6L·mol～-1·cm～-1;体系稳定性较好。应用本文方法对混合试样中Pt、Rh、Pd、Au进行同时测定,取得较满意的结果。     

双硫腙-离子液体萃取-原子吸收光谱法测定复杂体系样品中锌

将离子液体1-丁基-3-甲基咪唑六氟磷酸盐和双硫腙螯合剂用于复杂体系样品中锌的萃取。用原子吸收光谱法测定复杂体系样品中的锌含量。选择测定波长为516nm。锌的质量浓度在0.1~2.0mg·L-1范围内与其吸光度呈线性关系,检出限(3s/k)为0.69μg·L-1。方法应用于硫酸锌口服液样品中锌的测定,测定结果与药典法测定值相符。用标准加入法对方法的回收率进行试验,测得回收率在98.5%~101%之间,测定值的相对标准偏差(n=5)在1.9%~2.8%之间。     

Application of Multivariate Calibration Techniques to Simultaneous Spectrophotometric Determination of Copper and Iron Using 1‐(2‐Pyridylazo)‐2‐naphthol in AOT Micellar Solution

Multivariate calibration models (PCR and PLS) were developed for simultaneous determination of Fe(III) and Cu(II) with 1‐(2‐pyridylazo)‐2‐naphthol and AOT as chromogenic reagent and micellizing agent, respectively. In the presence of AOT the spectrum of Fe(III)‐PAN complex was shifted to higher wavelength and the overlapping with Cu‐PAN spectrum decreased. It seems that this anionic surfactant enters the structure of the Fe‐PAN complex to cause a shift in the absorption spectrum of it. The parameters controlling behavior of the systems were investigated and optimum conditions were selected. Sixteen ternary mixtures were selected as the calibration set. To select the number of factors in PCR and PLS algorithms, a cross validation method, leaving out one sample at a time, was employed. The calibration models were validated with 8 synthetic mixtures containing the metal ions in different proportions that were randomly designed. The best calibration model was obtained by using PLS regression. The method was successfully applied to simultaneous determination of copper and iron in biological samples.     

胶束电动毛细管色谱检测鱼肉中的七种生物胺

建立了一种利用胶束电动毛细管色谱同时检测鱼肉中组胺、腐胺、2-苯乙基胺、尸胺、色胺、亚精胺及精胺7种生物胺的方法。样品经6%过氯酸萃取后,由苯甲酰氯衍生化,以含0.06 mol/L脱氧胆酸钠的0.02 mol/L硼酸(pH 9.2)-甲醇(体积比为95∶5)混合液为电泳介质,电泳电压25 kV,温度25 ℃,检测波长214 nm,在12 min内实现了7种生物胺的完全分离。7种生物胺的浓度与其峰面积在一定的范围呈良好的线性关系,检出限除组胺为15 μg/g外,其余均为5 μg/g。迁移时间和峰面积的日内、日间相对标准偏差均小于5%。该法用于海鱼中7种胺类物质含量的测定,结果令人满意。     

以四(对羟基苯基)卟啉作显色剂组合导数分光光度法同时测定锌、镉的研究

本文利用“组合导数分光光度法”,在碱性介质中,以四(对-羟基苯基)卟啉作显色剂,以咪唑作催化剂,对锌、镉的同时测定进行了详细研究。该法使测定锌的表观摩尔吸光系数提高到10~6L·mol~(-1)·cm~(-1),同时解决了重叠谱带相互干扰的问题。对合成样品进行分析,结果令人满意。     

双波长分光光度法测定湿法炼锌净化液中的痕量锗

选择水杨基荧光酮－乳化剂ＯＰ－盐酸为显色体系，应用双波长分光光度法扣除硫酸锌的基体干扰，不分离直接测定了湿法炼锌过程中硫酸锌净化液中的痕量锗。测定范围在０－４０ｍｇ／Ｌ。本法应用于株洲冶炼厂锌净化液中锗的测定，结果与该厂长期的萃取－比色法结果相吻合，而测定速度较萃取－比色法至少提高了一倍。     

不去蛋白直接光度法测定血清锌

建立了一种在表面面活性剂Brij-35存在下,用2-(5-溴-2-吡啶偶氮)-5-二乙氨基酚(5-Br-PADAP)作显色剂不去蛋白直接光度法测定血清锌的新方法.用该法测定血清锌,显色络合物最大吸收波长为560nm,线性范围0～46.0μmol.L-1,表观摩尔吸光系数为1.08×105L.mol-1cm-1,回收率为97.5%～102.8%,批内变异系数(CV)和批间变异系数分别为2.3%与3.7%.与原子吸收分光光度法比较具有良好的相关性.回归方程为y=1.01x-0.26,r=0.9884,P＞0.05.4例健康人血清锌含量为9.5～24.7μmol.L-1(x-±2S).用该法进行血清锌测定,准确性和重现性均较好,且血清用量少,不必去蛋白,操作步骤简化,具有快速、简便、灵敏可靠等优点,适合临床应用.     

流动注射胶束增溶分光光度法同时测定镁砖中微量铁铝

本文研究了铁铝－ＣＡＳ－乳化剂ＯＰ胶束增溶体系的ＦＩＡ－光度法时测定镁砖中微量铁铝，该法操作简便，快速可靠，进样频率４５样次／ｈ，ＲＳＤ＜３．４％和５．８％。结果令人满意。     

用胶束毛细管电动色谱法分离三硝基甲苯异构体的研究

用胶束毛细管电动色谱法（ＭＥＫＣ）分离三硝基甲苯（ＴＮＴ）异构体。研究了背景电解质、十二烷基硫酸钠（ＳＤＳ）浓度、缓冲溶液添加剂Ｂｒｉｊ３５、ｐＨ等对分离的影响,找出了最佳分离条件,使三硝基甲苯的６种异构体在几分钟内达基线分离。     

CTMAB-Peregal O存在下锌镉的FIA同时测定

混合表面活性剂CTMAB-Peregal O对Zn~(2+)和Cd~(2+)与4-(2-吡啶偶氮)一问苯二酚的配合反应有协同增敏作用。由配合反应测得Zn~(2+)和Cd~(2+)的总量,用二乙基二硫代氨基甲酸钠掩蔽Cd~(2+)后,可测得Zn~(2+)量,再由计算求得Cd~(2+)量。研究了应用连续交替注入技术流动注射光度法同时测定Zn~(2+)和Cd~(2+)的方法。Zn”和Cd~(2+)的浓度分别在0～0.6μg/g和0～1.0μg/g时符合比耳定律。相对标准偏差<1.0%,进样频率180次/h。曾用此法测定了西湖水和工业废水中的Zn~(2+)和Cd~(2+),结果满意,并初步探讨了协同增敏作用的机理。     

胶束电动毛细管色谱法测定全血环孢霉素A

建立了用于临床测定全血环孢霉素A的毛细管电泳分析方法。采用未涂渍熔融石英毛细管(50μm×58.5 cm,有效长度50.0 cm),以含20 mmol/L磷酸氢二钠、50 mmol/L十二烷基硫酸钠的乙腈-水(1∶1)体系为电泳介质体系,采用乙醚萃取的前处理方法,有效去除了全血中内源性物质的干扰。通过柱上富集浓缩技术,提高检测灵敏度,检出限达70μg/L,实现了环孢霉素A的低浓度检测。     

Micellar solutions in shear: Viscosity and normal stress

We apply a recent non-equilibrium statistical mechanical theory for nonionic micellar solutions to study their viscoelastic properties. It is shown that shear-induced growth in average micellar size does not lead to the shear-thickening observed experimentally in ionic micellar systems, suggesting that intermicelle electrostatic interactions may be responsible for the viscosity build-up. Instead, we find shear thinning and gradual increase of normal stress throughout the studied range of shear rates.     

5-Br-PADAP直接光度法测定发锌

为建立一种简便、快速、灵敏的直接光度法测定发锌,将发样经无机化处理后,以5-Br-PADAP作为显色剂,在表面活性剂存在下直接光度法测定头发锌含量。结果表明,该法线性范围为0～612.0μmol/L,回收率为99.4％～102.4％,批内变异系数(CV)和批间变异系数分别为0.027和0.033。55例健康人头发锌含量为171.8±67.5μg(x±2s)。可见5-Br-PADAP直接光度法测定发锌具有操作简单、快速灵敏、结果可靠的优点,适合临床应用。     

聚乙烯醇增敏铋膜阳极溶出伏安法直接测定蜂蜜中锌

报道了一种快速测定蜂蜜中痕量Zn的电分析方法。蜂蜜不经消化,用二次蒸馏水直接溶解,可获得透明溶液。在pH=8.65的NH3.H2O-NH4C l缓冲溶液体系中,加入聚乙烯醇,采用玻碳电极镀铋做工作电极,饱和甘汞电极为参比电极,铂为辅助电极的三电极体系测定了3种蜂蜜中的Zn,获得了灵敏的阳极溶出峰,线性范围为0.4~8 mg/L,检出限为0.135 mg/L,加标回收率和样品测定RSD(n=6)分别为98%~100%和2.4%~4.5%。实验结果表明,本方法简便、快速、准确,还可以避免使用汞电极带来的污染。     

双硫腙分光光度法测定离子液体中Zn2+含量

离子液体是由带正电的离子和带负电的离子所构成的低熔点有机熔盐,在室温下一般呈液态状。室温离子液体(IL)以高导电性、宽的电化学窗口、较大的液态温度区间、广泛的溶解性和极低的蒸气压等奇特的物理化学性质,在电化学、萃取分离、有机合成等领域得到普遍应用[1-2]。在离子液