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1.
猪胰脏中铁钙镁铜铅锌镉锰钴镍的测定   总被引:2,自引:0,他引:2  
采用硝酸-过氧化氢在自动回流消化仪中消化猪胰脏,火焰原子吸收光度法测定铁、钙、镁、铜、锌、铅、镉、锰、钴、镍的含量。,方法简便,快速,结果令人满意,并对猪胰脏食用价值进行了评价。  相似文献   

2.
通过用四酸与微波消解法溶解样品对比,建立了用硝酸、盐酸、氢氟酸、高氯酸分解样品,采用电感耦合等离子体质谱法(ICP-MS)测定稀土矿中16种元素含量。方法采用103Rh作为内标消除干扰,确定了最优测定条件,16种稀土元素检出限为0.0029-0.0099ng/mL,测定范围为0.0005-0.020%。精密度试验、加标回收试验及标准物质检测,结果验证了方法的可行性及准确性。该方法简单易操作,结果可靠,能满足实验分析要求。  相似文献   

3.
Inductively coupled plasma atomic emission spectrometry (ICP-AES) was employed to determine Y, Sm, Eu, Gd, Dy, Ho and Er in high purity terbium oxide. Terbium oxide was dissolved in 0.5 mol/l HNO3 and nebulized into the plasma generated by a 56 MHz RF generator at 1.5 kW output power. Using a Jobin-Yvon 1-m Czenry-Turner high resolution, high dispersion scanning monochromator, lines mutually interference-free as well as free of interference from the matrix Tb were chosen for the seven analytes. A set of standards containing the analytes in the concentration range 0.01–1.0 gmg/ml with 1 mg/ml Tb was used for calibration. It was necessary to apply background correction to the gross analyte line intensities in order to obtain linear calibration plots for the analytes.  相似文献   

4.
建立了一种用电感耦合等离子发射光谱(ICP-AES)法测定玻璃成份的简便、快速、准确、精密度好的方法.研究了样品的处理、标准样品的配制、谱线干扰等问题,并采用和基体匹配的方法消除基体的影响,进行了标准样品的分析、对照、精密度等试验,均取得了满意的结果.  相似文献   

5.
3,4-Diamino-2-carbethoxy-5-cyanothieno(2,3-b)thiophene (1) was treated with ethylenediamine to afford 3,4-diamino-2,5-bi[2-(4,5-dihydro-1H-imidazole-2-yl]-thieno(2,3-b)thiophene 2 , which in turn was treated with chloroacety chloride to give bis[imidazolothieno diazepine] derivative 3 and with each of p-chlorobenzaldehyde, triethyl orthoformate, and Lawesson's reagent (LR) to yield bis[imidazolothienopyrimidine] derivatives 4-6 . Compound 1 was subjected to Mannich reaction to afford Mannich bases 7 and 8a , b . The later products ( 8a , b ) were treated with malononitrile yielding 9a and 9b . Treatment of compound 1 with CS 2 , NaOH and CH 3 I produced compounds 10 and 11 . The reaction of compound 10 with each of o-aminothiphenal, o-phenylenediamen, hydrazine hydrate, and phenylhydrazine afforded compounds 12a , b , 13a , b . Compound 1 was allowed to react with CS 2 , phenyl (benzoyl)isothiocyanate and phenylisocyanate to get the described products 14-19 , respectively. On reacting compound 1 with ethylcyanoacetate thieno(2,3-b)pyridine derivative 21 was obtained through the intermediate 20 . Finally, compound 1 was treated with malononitrile to yield compound 22 .  相似文献   

6.
建立电感耦合等离子体原子发射光谱(ICP–AES)法测定铬镍不锈钢中锰、铬、镍、硅、磷、铜、钼7种元素含量的方法。试样用盐酸与硝酸混合酸溶液溶解,采用溶解国家标准样品的方法制备校准曲线溶液,确定了元素最佳分析谱线。各元素的含量在其测试范围内与原子发射强度呈良好的线性关系,线性相关系数不小于0.999,7种元素的检出限在0.000 3%~0.003 0%之间。该方法应用于铬镍不锈钢标准样品的测定,测定值与认定值相符,测定值的相对标准偏差在0.12%~1.15%之间(n=8)。应用于铬镍不锈钢样品测定时,加标回收率在90%~110%之间。该方法操作简便、迅速,可满足日常铬镍不锈钢中多元素含量的检测需要。  相似文献   

7.
ICP-AES法测定铝中铁、硅、铜、镓、镁、锌、锰和钛   总被引:9,自引:0,他引:9  
用 50g L氢氧化钠溶液溶解铝样品 ,硝酸 (1 1 )酸化 ,以ICP AES测定其中铁、硅、铜、镓、镁、锌、锰和钛等 8种杂质元素。  相似文献   

8.
5-Ethoxycarbonyl-4-methyl-2-phenylpyrimidin-6(1H)-thione ( 3 ), which was prepared from the reaction of ethyl g -aminocrotonate 1 with benzoyl isothiocyanate ( 2 ) in refluxing acetone, was reacted with a series of halopgenated reagents to give S-alkyl derivatives 4a-g . Upon treatment of compounds 4a-c with sodium ethoxide were cyclized into thienopyrimidine 10a-c . Pyrimidinethione 3 was reacted with hydrazine hydrate to give hydroxypyrazolopyrimidine derivative 6 . The later compound was obtained by heating compound 4a with hydrazine hydrate under neat conditions, but when the reaction was carried using hydrazine hydrate in ethanol, the corresponding carbohydrazide 5 was produced.  相似文献   

9.
标题化合物C23H25对O3Cl是由邻氯苯甲醛与5,5-二甲基1,3-环己二酮在N,N-二甲基甲酸腹中反应而得。结构通过单晶X-射线衍射法确定,其晶体属于单科晶系,空间群=1632。晶体结构用直接法解出,使用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为R=0.054,Rw一0.063。在晶体结构中,吡喃环与苯环之间的两面角为92.43°。  相似文献   

10.
提出了用电感耦合等离子体原子发射光谱法(ICP-AES)测定70钛铁中共存的8种杂质元素(锰、磷、铜、铬、镍、钼、钒、铝)。试验表明:试样宜用浓盐酸3mL及浓硝酸3mL溶解,且在制作工作曲线时应加入相同量的酸溶解基体金属(即所加入的纯铁粉和纯钛粉),所选用的8种元素的分析谱线均为检出限低、且光谱干扰小或易于扣除者。制作工作曲线时采用基体匹配法,从而消除基体干扰,方法中8种元素的检出限(3s/b)在0.002~0.02mg·mL-1范围内。按所提出方法分析了一个70钛铁标样(YSBC15602),共测定了11次,上述8种元素的测定结果与已知值相符,测定值的相对标准偏差(n=11)在0.74%~4.11%范围内。  相似文献   

11.
New bis-phthalimides were synthesized by 2: 1 condensation of phthalic anhydride and tetrachlorophthalic anhydride with 1,2,4-triazole-3,5-diamine, pyridine-2,6-diamine, and 4-hydroxypyrimidine- 2,6-diamine. The synthesized compounds were characterized by elemental analyses and IR, 1H NMR, and mass spectra. Their interaction with calf thymus DNA (ct-DNA) was studied by UV-Vis spectrophotometry, cyclic voltammetry, and viscosity measurements, which revealed intercalative mode of binding to ct-DNA. Antibacterial activity of the synthesized compounds against Escherichia coli and Streptococcus mutans was assessed in vitro by the agar well diffusion method. The antioxidant activity of these compounds was estimated by DPPH assay.  相似文献   

12.
Analyses of milk and milk products are routinely performed by a number of dairy laboratories to control the quality of these products with regard to e.g. nutritional components and potential exposure to toxic elements. In order to improve and control the quality of such analyses the Community Bureau of Reference (BCR) has organized series of certification campaigns to produce reference material of milk certified for a variety of elements and compounds. The increasing demand is such that the stock of some of these materials is now exhausted. Consequently, the BCR decided to produce a new batch of CRM of skim milk powder certified for its contents of Ca, Cu, Cl, I, Fe, K, Mg, P, Pb, N, Na and Zn (CRM 063R). This material was carefully prepared (spray-drying) and its homogeneity and long term stability was verified. This paper presents the certification work performed.  相似文献   

13.
A simple and rapid method was developed for determination of benomyl, diphenyl (DP), o-phenylphenol (OPP), thiabendazole (TBZ), chlorpyrifos, methidathion, and methyl parathion in whole oranges. These compounds were extracted from a mixture of samples and anhydrous sodium acetate with ethyl acetate. The ethyl acetate extract was concentrated and cleaned up by passing through tandem solid-phase extraction columns consisting of anion-exchange and primary/secondary amine bonded silica. The eluate was concentrated and volume was adjusted with methanol for subsequent liquid chromatography (LC) and gas chromatography (GC). Benomyl (as methyl-2-benzimidazole carbamate, MBC), DP, OPP, and TBZ residues were determined by LC with fluorescence detection. Recoveries at 3 fortified levels (0.1, 1, and 10 micrograms/g) ranged from 63.9 to 97.4%, with coefficients of variation (CVs) of 1.6 to 15.5%. Limits of detection (LODs) were 0.01 microgram/g for DP, OPP, TBZ and 0.05 microgram/g for benomyl. Chlorpyrifos, methidathion, and methyl parathion residues were determined by GC with flame photometric detection. Recoveries ranged from 90.4 to 97.0%, with CVs of 2.1 to 5.9%. LODs were 0.005 microgram/g for chlorpyrifos and methyl parathion, and 0.01 microgram/g for methidathion.  相似文献   

14.
Deprotonation of pyrazine, pyridazine, pyrimidine, and quinoxaline using an in situ mixture of ZnCl2.TMEDA (0.5 equiv) and LiTMP (1.5 equiv) was studied. Pyrazine and pyrimidine were deprotonated in THF at room temperature, a result evidenced by trapping with I2. The competitive formation of dimer observed in net hexane was reduced by using cosolvents (TMEDA or THF). Starting from quinoxaline, the dimer formation took place in THF also, and mixtures of mono- and diiodides were obtained whatever the solvent and conditions used. A similar competitive formation of a diiodide was noted with pyridazine; the use of THF at reflux temperature nevertheless afforded the 3-iodo derivative in good yield.  相似文献   

15.
锰矿石样品用HNO3-HF-HClO4酸溶除硅后,对采用ICP-AES法测定其中的铁、铝、钛、钙、镁、磷时,同时测定钡、铅的相关条件进行了试验。主要对酸溶样能否分解重晶石或天青石等含钡矿物进行了探讨,测定了3个国家级标准样品。测定结果与标准值吻合。用标准加入法测得的钡和铅的回收率分别为96.0%-100.5%,97.1%~100.0%。用该法对含钡量较高的澳大利亚锰矿进行分析,测定结果的相对标准偏差为0-82%,并将测定结果与X荧光光谱法测定结果进行了比对。  相似文献   

16.
Summary A procedure is described for the determination of the cationic and anionic components in fluorozirconate glasses. Zirconium, barium, aluminium, lanthanum, sodium and hafnium were determined by inductively coupled plasma atomic emission spectrometry (ICP/AES) after dissolution of the sample with an acid mixture in a microwave oven. The fluorine content was evaluated with two different techniques, namely potentiometry with a fluoride ion-selective electrode (FISE) and ion chromatography (IC). In this case the sample was solubilized by fusion with sodium carbonate.  相似文献   

17.
不同炊具铁、铝或镍、铬溶出量的测定   总被引:1,自引:0,他引:1  
常用炊具铁、铝和不锈钢锅分别以水、水加醋煮沸10min后,用原子吸收分光光度法测定3种锅加水对应无奈的溶出量(mg/L)分别为铁11.60、铝21.41、镍0.06和铬0.07,而水加醋则其溶出量均明显增加,为加水的2.0-4.5倍。  相似文献   

18.
A rapid, accurate and sensitive method has been developed for the quantitative determination of four fluoroquinolone antimicrobial agents, enoxacin, norfloxacin, ofloxacin and ciprofloxacin, with high in-vitro activity against a wide range of Gram-negative and Gram-positive organisms.A Kromasil 100 C(8) 250 mm x 4 mm, 5 microm analytical column was used with an eluting system consisting of a mixture of CH(3)CN-CH(3)OH-citric acid 0.4 mol L(-1) (7:15:78 %, v/v). Detection was performed with a variable wavelength UV-visible detector at 275 nm resulting in limits of detection: 0.02 ng per 20 microL injection for enoxacin and 0.01 ng for ofloxacin, norfloxacin and ciprofloxacin. Hydrochlorothiazide (HCT) was used as internal standard at a concentration of 2 ng microL(-1). A rectilinear relationship was observed up to 2 ng microL(-1) for enoxacin, 12 ng microL(-1) for ofloxacin, 3 ng microL(-1) for norfloxacin, and 5 ng microL(-1) for ciprofloxacin. Separation was achieved within 10 min. The statistical evaluation of the method was examined by performing intra-day (n=8) and inter-day precision assays (n=8) and was found to be satisfactory with high accuracy and precision. The method was applied to the direct determination of the four fluoroquinolones in human blood serum. Sample pretreatment involved only protein precipitation with acetonitrile. Recovery of analytes in spiked samples was 97+/-6% over the range 0.1-0.5 ng microL(-1).  相似文献   

19.
In this work, a new method employing capillary electrophoresis (CE) for the determination of several species in biodiesel is introduced. The concentrations of inorganic species (Na+, K+, Ca2+, Mg2+, SO42−, and PO43−) and glycerol are of interest to the regulatory authorities due to their ability to form undesirable compounds in engines. Additionally, other species of low molecular weight (e.g., acetate, formate, and propionate) are of interest because they contribute towards increasing the acidity. These species are formed by the degradation of biodiesel and cause damage to engines and the environment. The cation separation was performed in background electrolyte (BGE) composed of 30 mmol L−1 of 2-(n-morpholino)ethanesulfonic acid (MES)/L-histidine (His), pH 6. The separation of anionic species was carried out in similar BGE with 0.2 mmol L−1 cetyltrimethylammonium bromide (CTAB) added. For glycerol, a neutral species, its oxidation with periodate was employed. This well-known reaction is specific to polyols and generates iodate. The amount of iodate produced by the reaction was determined by CE. The separation was carried out in approximately 1 min using BGE composed of 30 mmol L−1 acetic acid, pH 3. The analytical parameters evaluated were: linearity (r > 0.99), the RSD values for area and migration time were < 3.4% and 0.9%, respectively, and recovery was in the range of 89 to 107%.  相似文献   

20.
Single crystal of 2-[2-(4-methoxy-phenyl)-vinyl]-1-methylstilbazolium iodide (4MESI) was grown by the slow evaporation method. Single-crystal X-ray diffraction analysis reveals the formation of the title crystal. The density of the grown crystals was measured, and it was compared with theoretically calculated value. The FTIR and powder XRD of 4MESI were performed at room temperature. The different types of proton present in the crystal structure have been confirmed by NMR spectroscopic study. UV–Vis–NIR spectral studies reveal that 4MESI crystals are good optical transparency in the entire visible region. The photoluminescence spectrum of 4MESI shows violet and blue emission. Thermal stability and behavior of the grown crystal have been investigated by TG and DTG analysis. It shows that the grown crystal has melting point at 243 °C. Mechanical hardness of the grown crystals was estimated by Vickers microhardness tester. The grown crystals were also characterized by chemical etching and dielectric studies, and the results are discussed in detail.  相似文献   

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