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1.
OZONOLYSISOF4-ISOPROPYLIDENEPENTACYCLO(5.4.0.0 ̄(2,6).0 ̄(3,10).0 ̄(5,9))UNDECANE-8,11-DIONE¥JianGuangSUN;ZhuangSU;YongZhongYU(C...  相似文献   

2.
MICROWAVEEFFECTSONTHEOXIDATIVECOUPLINGOFMIETHANEOVERLi_2SO_4/BaCe_(0.93)La_(0.07)O_3¥ChangLinCHEN;PinJieHONG;ShuShanDAI;Guang...  相似文献   

3.
偏最小二乘催化极谱法同时测定铂,钯,铑   总被引:6,自引:0,他引:6  
应用M273A电化学系统中的线性扫描技术,确定了0.75mol/LH2SO4-1.5%NH4Cl-2.8mmol/L(CH2)6N4-0.0025%N2H4.H2SO4为偏最小二乘极谱法同时测定Pt、Pd、Rh的最佳极谱体系。Pt、Pd、Rh的线性范围为3.2mg/L、0-15.0mg/L和0-1.0mg/L。模拟样品及实际样品的回收率在90.3-107.7%之间。  相似文献   

4.
在0.2mol/LNaOH-0.04mol/LH3PO4-0.02mol/L(NH4)2SO4-0.04mol/LCH3COOH溶液中,精氨酸(Arg)在苯甲醛存在下产生一灵敏的吸附波。实验证明电活性物质为α-苯亚甲基精氨酸,其电极反应机理是分子内α->C=N基团被还原为亚胺。用该吸附波可在1×10(-3)~2×10(-6)mol/L范围内分析蛋白质中的Arg。  相似文献   

5.
STRUCTURALMODIFICATIONOF11-ISOPROPYLIDENEendo-TRICYCLO[6.2.1.0 ̄(2,7)]UNDECA-4,9-DIENE-3,6-DIONETOIMPROVETHESTABILITY¥XiaoPeiG...  相似文献   

6.
SYNTHESIS OF 4-(2,3-DIMETHOXY-4-ISOPROPYLBENZYL)-3-ETHOXYCARBONYLMETHYL-2-CYCLOHEXENONESYNTHESISOF4-(2,3-DIMETHOXY-4-ISOPROPY...  相似文献   

7.
基于亚硝化反应的极谱法测定亚硝酸根的研究   总被引:4,自引:0,他引:4  
提出了一种基于在酸性介质中甲基紫与亚硝酸根发生亚硝化反应,极谱法测定亚硝酸根的新体系。亚硝化产物在-0.75V(vs.SCE)处2.5次微分波的波高与NO2-的质量浓度在2.0×10-3~2.0×10-2mg/L(S=4μA),4.0×10-3~1.6×10-1mg/L(S=0.02mA)范围内成直线关系。该法重复性好,且大多数常见的阴、阳离子不干扰,用于污水中痕量NO2-的测定,结果满意。  相似文献   

8.
THESYNTHESISANDCRYSTALSTRUCTURECOMPLEXOFSCHIFFBASECONTAININGS·N-Cd_3|CH_3O(O)C_6H_3CH=NNHC(S)NH_2|4·(CH_3COO_2·1/2[CH_3S(O)CH_3]·?..  相似文献   

9.
SYNTHESISANDCHARACTERIZATIONOF(PPh_3)_3Co(μ-CO)_2V(CO)_2CpAND(PPh_3)HPt(μ-CO)(μ-PPh_2)V(CO)_2CpChangPingSHAO(DalianInstituteofCh?..  相似文献   

10.
UNUSUAL FORMATION OF ORGANO-NEODYMIUM AND -SAMARIUM CATIOHS AND X-RAY STRUCTURE OF[(MeOCH_2CH_2C_5H_4)_2Sm(thf)][Co(CO)_4]UNUSUA...  相似文献   

11.
离子色谱法分析保险粉工业回收甲酸钠中的阴离子   总被引:4,自引:0,他引:4  
冯龙胜  丁明玉 《色谱》1999,17(4):376-378
利用单柱阴离子交换色谱法测定了保险粉工业回收产品中的甲酸,Cl-,SO,NO,羟乙基硫代硫酸盐,SO和S2O。以1.8mmol/L邻苯二甲酸和1.35mmol/L三羟甲基氨基甲烷的混合溶液作淋洗液,流速为1.0mL/min时,分离效果良好。7种离子的加标回收率在96%~102%之间,检测下限在0.2~5mg/L之间,方法准确、简便。  相似文献   

12.
Mehra HC  Frankenberger WT 《Talanta》1989,36(9):889-892
Single-column ion-chromatography (SCIC) was investigated as a routine, rapid, precise and selective analytical method for the determination of chromium(VI) in aqueous extracts of soil and sewage sludge. Chromatographic parameters were optimized for determination of Cr(VI), NO(-)(3) and SO(2-)(4). A low-capacity resin-based column was used for the separation and the anions were determined by conductometric detection. p-Hydroxybenzoic acid (5mM) at pH 8.5 was used as the eluent. The limit of detection, defined as S/N = 3, was 92 mug/l. The resolution between Cr(VI) and SO(2-)(4) was 2.8, the precision ranged from 0.9% for NO(-)(3) to 2.0% for Cr(VI) with a 500-mul injection. The SCIC results for Cr(VI) agreed closely with those obtained by inductively coupled argon-plasma emission and spectrophotometry.  相似文献   

13.
A method has been developed for the simultaneous determination of a range of aromatic amines using cation-exchange chromatography performed on a standard ion chromatography column using d.c. amperometric detection. The analytes separated were 2,4- and 2,6-toluenediamine (2,4- and 2,6-TDA), aniline, o-toluidine, benzidine, p-chloroaniline, 4,4'-diaminodiphenyl (4,4'-DDP), m-nitroaniline and 1-naphthylamine. A Dionex CS12 column was used with gradient elution from an initial eluent of 5% CH3CN+35 mM H2SO4 to 27% CH3CN+35 mM H2SO4 (at 35 min). Detection limits in the range 2.6-22.6 microg/l were observed for all analytes except m-nitroaniline, for which the detection limit was 201 microg/l. Linear calibrations and good precision were observed and the method was applied to the determination of benzidine, p-chloroaniline and 1-naphthylamine in wastewater samples. Further, the separation was also used (after some modification of the eluent conditions) for the determination of 2,4- and 2,6-toluene diisocyanate (2,4- and 2,6-TDI) and 4,4'-methylenediphenyl diisocyanate (4,4'-MDI) after their hydrolysis to 2,4-TDA, 2,6-TDA and 4,4'-DDP. Detection limits for 2,6- and 2,4-TDI and 4,4'-MDI were 3.8, 8.2, and 11.2 microg/l, respectively. The method was applied to the determination of diisocyanates in air.  相似文献   

14.
采用离子色谱法测定农村饮用水中F-、Cl-、NO2-、Br-、NO3-和SO42-等6种阴离子的含量。水样经Ion Pac AG19保护柱及Ion Pac AS19分离柱分离,以20.00mmol·L-1氢氧化钾溶液为淋洗液,采用抑制电导器检测。F-、NO2-和Br-在4mg·L-1以内,Cl-、NO3-和SO42-在40mg·L-1以内呈线性关系,检出限(2S/N)在0.002~0.012mg·L-1之间。方法用于水样中6种阴离子的测定,加标回收率在98.0%~101.3%之间,相对标准偏差(n=6)在0.83%~2.7%之间。  相似文献   

15.
30%亚硫酸氢钠溶液样品中Cl-和SO2-4的同时测定   总被引:3,自引:0,他引:3  
陆克平 《色谱》2005,23(2):205-207
建立了采用离子色谱测定30%亚硫酸氢钠溶液样品中的氯化钠和硫酸钠含量的新方法。采用IonPac AS14分析柱,选择三乙醇胺为亚硫酸氢钠的稳定剂,以丙酮为有机改进剂,淋洗液组成为1.5 mol/L Na2CO3-3.5 mol/L NaHCO3-10% (体积分数)(CH3)2CO,流速为1.0 mL/min,抑制电导检测。实验结果表明,氯离子、硫酸根离子分别在0.05~1.5 mg/L,0.20~15 mg/L时,其峰面积与质量浓度呈线性关系,相关系数均大于0.999,检出限分别为0.01 mg/L和0.03 mg/L。该法用于实际样品分析,操作便捷,结果可靠。  相似文献   

16.
甲基膦酸二甲庚酯萃取色谱法分离金、铂的研究   总被引:1,自引:0,他引:1  
江瑜  张忠信  潘仲巍 《分析化学》1994,22(8):794-797
本文研究了以4.0mol/L H_2SO_4-0.50mol/L MgSO_4 为流动相,以硅烷化硅球负载的甲基膦酸二甲庚酯(P350)作固定相。萃取色谱法使微量铂、金与常见贱金属分离,富集在色谱柱上的铂和金分别用0.10mol/L HCl和1.0%Na_2SO_2溶液洗脱进行连续分离与测定。经实际样品的试用考核,结果令人满意。  相似文献   

17.
采用氧弹燃烧法对海藻酸钠样品进行燃烧,用碳酸钠作为吸收液进行吸收,建立了离子色谱-抑制电导法检测海藻酸钠中阴离子的方法.实验采用SH-AC-1型离子交换色谱柱,最佳色谱条件:以3.6 mmol/L碳酸钠为淋洗液,柱温45℃,流速0.7 mL/min.在此条件下,可同时分离Cl-、SO42-离子,且色谱峰型对称,所测C1...  相似文献   

18.
The simultaneous determination of inorganic anions by ion chromatography using a dynamically coated graphitized carbon column with cetyltrimethylammonium (CTA) ions was investigated with suppressed conductivity detection. Column preparations with CTA and sodium carbonate-sodium hydrogencarbonate concentration in the eluent were examined to optimize the separation of seven common anions (F-, Cl-, NO2-, Br-, NO3-, HPO(4)2- and SO(4)2-). Calibration curves were linear from 0.5 to 5 micrograms/ml for F-, from 1.0 to 10 micrograms/ml for Cl-, from 1.5 to 15 micrograms/ml for NO2-, from 2.0 to 20 micrograms/ml for Br- and NO3-, from 5.0 to 50 micrograms/ml for HPO(4)2- and from 3.0 to 30 micrograms/ml for SO(4)2- with correlation coefficients (r) of 0.999 or better. The relative standard deviations of peak areas were between 0.3 and 0.9% for 10 repeated measurements. The application of this newly developed method was demonstrated by the determination of inorganic anions in the water for pharmaceutical purposes. Using CTA-Br as the coating agent, a permanently coated ion-exchange column was obtained, which allowed efficient separations of seven anions without adding any coating agent to the eluent.  相似文献   

19.
ICP-MS is used as an element selective detector for chromium species in aquatic samples using a coupled columm system consisting of a cation guard column and an anion column. The effects of large concentrations of disturbing ions, like NO(3)(-), Cl(-), CO(3)(2-) and SO(4)(2-), are discussed and the comparison with the use of different chromium isotopes for data acquisition is given. Quite low concentrations such as 100 mg/l of CO(3)(2-), 10 mg/l Cl(-) and even 5 mg/l SO(4)(2-) can cause an overestimation of chromium if not properly resolved1995 / Accepted: 24 October 1995  相似文献   

20.
An ion chromatography (IC) method has been proposed for the determination of seven common inorganic anions (F(-), H(2)PO(4)(-), NO(2)(-), Cl(-), Br(-), NO(3)(-), and SO(4)(2-)) and/or five common inorganic cations (Na(+), NH(4)(+), K(+), Mg(2+), and Ca(2+)) using a single pump, a single eluent and a single detector. The present system used cation-exchange and anion-exchange columns connected in series via a single 10-port switching valve. The 10-port valve was switched for the separation of either cations or anions in a single chromatographic run. When 1.0mM trimellitic acid (pH 2.94) was used as the eluent, the seven anions and the five cations could be separated on the anion-exchange column and the cation-exchange column, respectively. The elution order was found to be F(-)相似文献   

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