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1.
该研究合成了一种新型水溶性大π共轭高分子———聚吡咯 {2 ,5 [ 二( 对二甲氨基苯甲烯)]}(PPDMAB) ,它能溶于强酸的水溶液,在1mol/L 的盐酸中溶解度为0-5 ~1-0g/100mL.通过EA、XPS、FT IR、UV Vis NIR、In situ UV Vis NIR 对PPDMAB进行了结构表征.通过质子化、碘掺杂、浓硫酸(98 % ) 掺杂等处理,PPDMAB的电导率提高2~4 个数量级(δ= 10 - 7 ~10- 5S/cm) .在质子化、去质子化的过程中PPDMAB发生了可逆的颜色变化,本征态( 综色) 质子态( 墨兰色) .  相似文献   

2.
CuZSM-5分子筛上苯酚羟化制苯二酚   总被引:4,自引:0,他引:4  
在Na2O-SiO2-CuO-H2O体系中以15%TPABr-85%HMDA为模板剂合成了CuZSM-5分子筛,并用XRD,IR及SEM等方法进行了表征,考察了CuZSM-5分子筛催化苯酚与过氧化氢的羟化活性,研究了催化剂用量、反应温度、反应时间及n(PhOH)/n(H2O2)等对羟化活性的影响.  相似文献   

3.
FETV-ICP-AES 直接测定中药漏芦中微量稀土元素的研究   总被引:2,自引:0,他引:2  
提出了以聚四氟然悬浮为氟化剂,氟化电热蒸发(FETV)等离子体发射光谱法(ICP-AES)直接测定中药漏芦中微量稀土元素La、Eu、Yb和Y的方法,改进了ETV与ICP之间的气路接口,研究了影响待测元素信号强度的有关因素,在优化实验条件下,方法的检出限为1.0-3.8ng/mL,相对标准偏差为2.7%-4.4%。此法已应用于中药漏芦中微量稀土元素的测定。  相似文献   

4.
用HPLC/ECD法测定血小板5-HT,运用 WatersμBondapak C柱,3,4二羟基苄胺(DH-BA)作内标,以 0.07 mol/L乙酸钠缓冲液+乙腈为流动相(20+1),每1L缓冲液含 0.05 mol/L柠檬酸、2.5 mmol/L庚烷磺酸钠、0.1mmol/L Na_2EDTA,流速0.8 mL/min。DHBA和 5-HT的保留时间分别为5.4和11.5 min,线性范围为0.025~1mg/L(r= 0.9997)。5-HT日内 RSD低于1.87%,日间RSD低于8.54%,方法回收率为100.4%±2.3%。提示本方法快速简便,灵敏准确,适用于临床基础研究。  相似文献   

5.
该研究合成了一种新型水溶性大π共轭高分子-聚吡咯-{2,5-〔二(对二甲氨基苯甲烯)〕}(PPDMAB),它地强酸的水溶液,在1mol/L的盐酸中溶解度为0.5~1.0g/100mL,通过EA、XPS、FT-IR、UV-Vis-NIR、In-situUV-Vis-NIR对PPDMAB进行了结构表征。通过质子化、碘掺杂、浓硫酸(98%)掺杂等处理,PPDMAB的电导率提高2~4个数量组(&=1-^-7  相似文献   

6.
用气相色谱-微波等离子体-原子发射光谱检测器(GC-MIP-AES)测定水中微量无机砷.在酸性条件下,As(Ⅲ)与2,3-二巯基丙醇(BAL)反应生成挥发性的环状二硫胂衍生物,被甲苯萃取.在181.379nm和189.041nm处GC-MIP-AES分别检测衍生物中硫砷的发射信号.检出限为15pg(以砷计),加标回收率96.35-106.03%,变异系数<4.5%.  相似文献   

7.
SILICOM-OXYGEM-SILICONBOND-BREAKINGBYMAGNESIUMDIETHOXIDE¥JiMaoLIN(DepartmentofChemistry,ShandongUniversity,Jinsa,250100.)Abst...  相似文献   

8.
SynthesisandCrystalStructureof Bis[Bis(Cyclopentylcyclopentadienyl)Methyl-Erbium][(C_5H_9C_5H)_4)_2ErCH_3]_2JinJi-Zhu;ZhuangXiu-...  相似文献   

9.
本文研究了一个简便,快速的用ICP-AESBi(Pb)SrCaCuPbO,Bi(Pb,Sb)Sr-CaCuO,Bi(Pb,Y)SrCaCuO超导体块材及薄膜中Bi,Pb,Sb,Y,Sr,Ca,Cu含量的方法。样品溶解在50%HCl及50%HNO3的混合酸中,直接引入等离子体光谱中进行测定。对共存元素的相互干扰及基片成分的干扰进行了研究。分析了大量样品,给出了各组分的挥发情况及Pb的挥发量与烧结温度  相似文献   

10.
在0.2mol·L ̄(-1)NH_4Cl-NH_3·H_2O底液中,(pH为9.26),得到一个极为灵敏的Fe(Ⅲ)-TEA-5-Br-PADAP-H_2O_2配合吸附催化波,其峰电位为-0.71V(vs.SCE)。铁浓度在1.8×10 ̄(-10)~5.4×10 ̄(-6)mol·L ̄(-1)范围内与二阶导数波高呈线性关系。对该极谱波的性质进行了研究,证明是一种配合吸附催化波,并成功地应用于各类水样,钒催化剂中微量或痕量铁的测定。  相似文献   

11.
采用电感耦合等离子体发射光谱法测定了铜渣精矿中砷、锑、铋、铅、锌、镁的量。其测定范围:ω(As):0.05%~0.45%,ω(Sb):0.07%~0.30%,ω(Bi):0.01%~0.20%,ω(Pb):1.00%~4.50%,ω(Zn):1.00%~4.50%,ω(Mg):0.10%~1.00%。经加标回收实验,各元素的加标回收率为92%~104%(n=3),相对标准偏差(RSD)小于5%(n=11)。方法准确快速可靠,适用于铜渣精矿中砷、锑、铋、铅、锌、镁量的同时测定.  相似文献   

12.
建立了电感耦合等离子体原子发射光谱法(ICP-AES)测定粗铅中Cu,As,Sb,Bi 4种元素的定量分析方法。通过实验选择327.395,193.696,187.052,223.061nm分别作为Cu,As,Sb,Bi的分析谱线,方法的检出限均小于0.010μg/mL。方法的回收率在96%~104%,精密度实验结果表明,相对标准偏差(RSD,n=6)均小于3%,能满足日常分析对粗铅中杂质元素的快速检测要求。  相似文献   

13.
Li ZX  Guo YA 《Talanta》2005,65(5):1318-1325
A new and sample technique for the simultaneous determination of trace arsenic, antimony, bismuth and selenium in biologic samples by hydride generation-four-channel nondispersive atomic fluorescence spectrometry was development. The conditions of instrumentation and hydride generation of arsenic, antimony, bismuth and selenium were optimized. For reducing hexavalent Se to the tetravalent state was to heat the sample with 6 mol l−1 HCl, and then pre-reducing pentavalent As and Sb to the trivalent state was achieved by the addition of 0.05 mol l−1 thiourea. The interferences of coexisting ions were evaluated. Under optimal conditions, the detection limits for As, Sb, Bi and Se were determined to be 0.03, 0.04, 0.04 and 0.03 ng ml−1, respectively. The precision for seven replicate determinations at the 5 ng ml−1 of As, Sb, Bi and Se were 0.9, 1.2, 1.3 and 1.5% (R.S.D.), respectively. The proposed method was successfully applied to the simultaneous determination of As, Sb, Bi and Se in a series of Chinese certified biological reference materials using simple aqueous standard calibration technique, the results obtained are in good agreement with the certified values.  相似文献   

14.
A slurry sampling inductively coupled plasma mass spectrometry (ICP-MS) method has been developed for the determination of Ge, As, Cd, Sb, Hg and Bi in cosmetic lotions using flow injection (FI) vapor generation (VG) as the sample introduction system. A slurry containing 2% m/v lotion, 2% m/v thiourea, 0.05% m/v l-cysteine, 0.5 μg mL−1 Co(II), 0.1% m/v Triton X-100 and 1.2% v/v HCl was injected into a VG-ICP-MS system for the determination of Ge, As, Cd, Sb, Hg and Bi without dissolution and mineralization. Because the sensitivities of the analytes in the slurry and that of aqueous solution were quite different, an isotope dilution method and a standard addition method were used for the determination. This method has been validated by the determination of Ge, As, Cd, Sb, Hg and Bi in GBW09305 Cosmetic (Cream) reference material. The method was also applied for the determination of Ge, As, Cd, Sb, Hg and Bi in three cosmetic lotion samples obtained locally. The analysis results of the reference material agreed with the certified value and/or ETV-ICP-MS results. The detection limit estimated from the standard addition curve was 0.025, 0.1, 0.2, 0.1, 0.15, and 0.03 ng  g−1 for Ge, As, Cd, Sb, Hg and Bi, respectively, in original cosmetic lotion sample.  相似文献   

15.
A simple and very inexpensive in-situ nebulizer/hydride generator was used with inductively coupled plasma mass spectrometry (ICP-MS) for the determination of As, Sb, Bi and Hg in water samples. The application of hydride generation ICP-MS alleviated the sensitivity problem of As, Sb, Bi and Hg determinations encountered when the conventional pneumatic nebulizer was used for sample introduction. The sample was introduced by flow injection to minimize the deposition of solids on the sampling orifice. The elements in the sample were reduced to the lower oxidation states with L-cysteine before being injected into the hydride generation system. This method has a detection limit of 0.003, 0.003, 0.017 and 0.17 ng ml−1 for As, Bi, Sb and Hg, respectively. This method was applied to determine As, Sb, Bi and Hg in a CASS-3 nearshore seawater reference sample, a SLRS-2 riverine water reference sample and a tap water collected from National Sun Yat-Sen University. The concentrations of the elements were determined by standard addition method. The precision was better than 20% for most of the determinations.  相似文献   

16.
Li Z  Yang X  Guo Y  Li H  Feng Y 《Talanta》2008,74(4):915-921
Chemical vapor generation (CVG) coupled with non-dispersive atomic fluorescence spectrometry (NDAFS) has been widely used for determination of vapor-forming elements, but most of such works have been focused on single element analysis, and reports dealing with more than three elements simultaneous determination by CVG-NDAFS are rare. In this work, a sensitive and robust analytical procedure for the simultaneous determination of arsenic, antimony, bismuth and mercury in geological materials using vapor generation-four-channel non-dispersive atomic fluorescence spectrometry has been developed. The conditions of instrumentation and vapor generation of arsenic, antimony, bismuth and mercury were optimized. The optimized concentrations of KBH(4) and HCl required for analytes generation were 1.3% (m/v) and 20% (v/v), respectively. The interferences of coexisting ions and mutual hydride interferences were investigated carefully. One thousand milligrams per litre of Fe(3+); 500mgl(-1) of Pb(2+), Zn(2+), Mn(2+); 50mgl(-1) Cu(2+), Ni(2+), Cr(6+), Co(2+); 10mgl(-1) Ag(+) and 5mgl(-1) Au(3+) does not interfere with the determination of As, Sb, Bi and Hg. Associating a dilution of 1:250 (m/v) in the procedure of sample pretreatment, the tolerant concentrations of As, Sb, Bi and Hg in real geological materials are 2500, 1000, 250 and 5000ppm, respectively. Under optimal conditions, the detection limits for As, Sb, Bi and Hg were determined to be 0.068, 0.047, 0.037 and 0.008ngml(-1), respectively. The precisions for seven replicate determinations at the 5ngml(-1) of As, Sb, Bi and 1ngml(-1) of Hg were 0.47, 0.60, 0.97 and 0.93% (R.S.D.), respectively. Sample digestion was carried out on 500mg sample with 3ml HNO(3) and 10ml HCl, followed by addition of thiourea solution for the quantitative reduction of As(V), Sb(V) to As(III), Sb(III). The proposed method was successfully applied to the simultaneous determination of As, Sb, Bi and Hg in a series of certified geological reference materials using simple aqueous standard calibration technique. The results obtained are in good agreement with the certified values.  相似文献   

17.
采用化学蒸气发生-四通道原子荧光光谱法测定了高纯金中的痕量砷、锑、铋和碲。用乙酸乙脂萃取分离金,水相还原后采用化学蒸气发生-四通道原子荧光光谱法测定高纯金中的痕量砷、锑、铋和碲。在最佳条件下,方法对As,Sb,Bi,Te的检出限分别为0.04,0.05,0.04,0.03 ng/mL(3σ);测定精密度分别为0.98,0.89,0.94,0.99%(对10 ng/mL As,Sb,Bi和Te混合标准,n=7)。方法对实际样品中的As,Sb,Bi,Te进行了同时测定,测定结果与标准方法无明显差异,各元素的加标回收率为95%~105%。  相似文献   

18.
研究了用酸分解试样后不需分离基体直接用电感耦合等离子体原子发射光谱(ICP-AES)法测定铅锭中银、铜、铋、砷、锑、锡、锌、铁、镉、镍、铊11种杂质元素的方法。优化了样品前处理条件及仪器检测条件。方法的检出限为0.0012~0.0168μg/mL,回收率为89%~110%,RSD为2.3%~5.0%。方法简便快速,检出限低,精密度和准确度能满足铅锭中杂质元素的检测要求,具有较强的实用性和可操作性,可用于铅锭中杂质元素的测定。  相似文献   

19.
A headspace single-drop microextraction (HS-SDME) method has been developed in combination with electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) for the simultaneous determination of As, Sb, Bi, Pb, Sn and Hg in aqueous solutions. Vapor generation is carried out in a 40 mL volume closed-vial containing a solution with the target analytes in hydrochloric acid and potassium ferricyanide medium. Hydrides (As, Sb, Bi, Pb, Sn) and Hg vapor are trapped onto an aqueous single drop (3 µL volume) containing Pd(II), followed by the subsequent injection in the ETV. Experimental variables such as medium composition, sodium tetrahydroborate (III) volume and concentration, stirring rate, extraction time, sample volume, ascorbic acid concentration and palladium amount in the drop were fully optimized. The limits of detection (LOD) (3σ criterion) of the proposed method for As, Sb, Bi, Pb, Sn and Hg were 0.2, 0.04, 0.01, 0.07, 0.09 and 0.8 µg/L, respectively. Enrichment factors of 9, 85, 138, 130, 37 and 72 for As, Sb, Bi, Pb, Sn and Hg, respectively, were achieved in 210 s. The relative standard deviations (N = 5) ranged from 4 to 8%. The proposed HS-SDME-ETV-ICP-MS method has been applied for the determination of As, Sb, Bi, Pb, Sn and Hg in NWRI TM-28.3 certified reference material.  相似文献   

20.
建立了微波消解-内标法-标准加入-ICP-MS法测定高纯黄金中铝、砷、铋、铬、铁、铅、锑、硒、碲、铱等痕量元素的分析方法。从试样溶解方式、内标元素及同位素的选择、仪器检测模式的优化及降低基体抑制效应等方面进行优化。实验加标回收率为99.5%~110%,相对标准偏差(RSD)为0.050%~6.5%。实验的准确度和精密度良好,操作便捷。  相似文献   

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