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1.
Zusammenfassung Für die folgenden 20 Elemente wurden die Grundlagen für eine halbquantitative Konzentrationsbestimmung mit Hilfe des Laser-Mikrospektralanalysators ermittelt, und zwar differenziert für Untersuchungen an oxidischen und an metallischen Materialien: Mg, Al, Si, Cr, Mn, Co, Ni, Cu, Zn, Ga, Ge, Pd, Ag, Cd, In, Sn, Sb, Pb, Bi, Fe bzw. Au.
Principles of semi-quantitative determination of 20 elements by laser-microspectroscopy
The principles for the determination of the following 20 elements by Laser-microspectroscopy have been investigated separately for oxidic and metallic materials: Mg, Al, Si, Cr, Mn, Co, Ni, Cu, Zn, Ga, Ge, Pd, Ag, Cd, In, Sn, Sb, Pb, Bi, Fe resp. Au.
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2.
Summary The catalytic effects of peroxidase-like metalloporphyrins (Me-P) on the fluorescence reaction of homovanillic acid with hydrogen peroxide have been studied. These metalloporphyrins are the complexes of Mn with tetrakis(carboxyphenyl)porphyrin (TPPC) and trikis(sulfophenyl)porphyrin(TPPS3), Fe, Co, Ni, Cu, Zn, Ag and Sn with tetrakis(sulfophenyl)porphyrin(TPPS4), and Rh, Pt and Pd with tetrakis(N-methylpyridiniumyl)porphyrin-(TMPyP) and hemin. The complexes of Mn, Fe, Co, Rh and Pt with porphyrins catalyzed the formation of the fluorescence product, while the complexes of Ni, Cu, Zn, Ag, Sn and Pd did not. Traces of hydrogen peroxide and glucose can be determined using the metalloporphyrins. The characteristics of peroxidase-like metalloporphyrins have been compared with those of horseradish peroxidase (HRP).  相似文献   

3.
Donaldson EM 《Talanta》1976,23(6):417-426
The solvent extraction of metal xanthates is reviewed with emphasis on the characteristics and analytical uses of ethyl xanthate complexes. Elements reviewed include As, Sb, Bi, Cd, Co, Cu. Cr, Ga, Au, In, Fe, Pb, Mn, Hg, Mo, Ni, Pd, Pt, Re, Ag, Se, Te, Tc, Tl, Sn, U, V and Zn.  相似文献   

4.
Zusammenfassung Zur Bestimmung geringer Gehalte der Elemente Au, Hg, Cu, Cd, As, Sb, Sn, Ga, Fe, In, Cr, Co, Ni, Mn, Zn, Mo und W in hochreinem Aluminium wurde eine aktivierungsanalytische Methode ausgearbeitet. Bei einer Einwaage von insgesamt etwa 1 g kann die Analyse mit Nachweisempfindlichkeiten zwischen 1 · 10–6 (Au) und 0,5 ppm (Fe) durchgeführt werden. Die erforderlichen chemischen Trennoperationen werden beschrieben.
Summary A method is described for the determination of low contents of the elements Au, Hg, Cu, Cd, As, Sb, Sn, Ga, Fe In, Cr, Co, Ni, Mn, Zn, Mo and W in high-purity aluminium by activation analysis. With sample weights of about 1 g sensitivities are obtained between 1 · 10–6 (Au) and 0,5 ppm (Fe). The chemical separation procedures required are described.


Den Herren W. Schweighofer und U. Grahmann möchten wir an dieser Stelle für ihre wertvolle Mitarbeit hei der Ausarbeitung und Durchführung der Analysen danken.

Herrn Prof. Dr. W. Geilmann zum 75. Geburtstag gewidmet.  相似文献   

5.
Zusammenfassung Zur Anreicherung von Spurenelementen aus Lösungen reinster Thalliumpräparate wird die Matrix Thallium als TlJ ausgefällt. Dabei bleiben die Spuren Mg, Zn, Al, Ga, In, Fe, Co, Ni, Mn, Sn, La, Ce, Th und U quantitativ in Lösung, während Bi, Cu, Pb und Cd sowie die Edelmetalle Ag, Hg, Pd, Au und Pt vom Niederschlag mitgerissen werden. Die Adsorption der für die Reinheitsprüfung des Thalliums wichtigen Elemente Bi, Cu, Pb und Cd kann verhindert werden, wenn sie mit Hilfe von ÄDTA in Komplexanionen übergeführt werden. Als Fällungsmittel wird NaJ verwendet. Zur spektrochemischen Bestimmung werden Pb, Cd, Bi, Ni, Co und In als DDTC-Komplexe mit Chloroform extrahiert. Nach Zusatz einer Mischung von Lithiumcarbonat-Kohle und den Referenzelementen Sn und Pd wird der Eindampfrückstand im Gleichstrombogen analysiert. Cu und Fe werden photometrisch bestimmt.
Enrichment and spectrochemical determination of trace elements in high-purity thallium preparations
For the enrichment of trace elements in solutions of high-purity thallium samples, thallium is precipitated in form of TlI. In this process the noble metals Ag, Hg, Pd, Au, Pt and also Bi, Cu, Pb and Cd will be co-precipitated, whereas many other elements (Mg, Zn, Al, Ga, In, Fe, Co, Ni, Mn, Sn, La, Ce, Th, U) will remain completely in solution. The adsorption of the four elements Bi, Cu, Pb, Cd, which are important for the purity control of thallium compounds, can be prevented, if they are complexed with EDTA to form complex anions. The precipitating reagent is NaI. For the spectrochemical determination of Pb, Cd, Bi, Ni, Co, and In, the trace elements are extracted as DDTC complexes with chloroform. After the addition of a mixture of Li2CO3, carbon, and the reference elements Sn and Pd, the sample is analysed, using the d.c. arc. Cu and Fe are determined spectrophotometrically.


Wir danken dem Fonds der chemischen Industrie für die finanzielle Unterstützung dieser Arbeit.  相似文献   

6.
Donaldson EM 《Talanta》1976,23(6):411-416
The chloroform extraction of 32 elements (Fe, Co, Ni, Zn, Cd, Ge, Sn, Pb, V, As, Sb, Bi, Cu, Ag, Au, Mn, Re, Ga, In, Tl, Ce, Se, Te, Cr, Mo, U, Pt, Pd, Rh, Ir, Ru and Os) from O.1-10M hydrochloric acid media in the presence of potassium ethyl xanthate has been studied. The oxidation states in which some elements react, and potential analytical separations, are discussed. Pd(II), As(III) and Se(IV) are completely extracted as ethyl xanthate complexes, Te(IV) is almost completely extracted, and Au(III) is largely extracted over the range of acid concentration investigated. Mn(II), Zn, Rh(III), Ir(IV), Ru(III), Os(IV), Cr(III), Cr(VI), Ce(III) and Ce(IV) are not extracted. Ge is partly extracted from 6-10M media as the chloro-complex. Depending on the acid concentration, the remaining elements are all partially extracted as xanthate complexes.  相似文献   

7.
Bis(3-cyano-pentane-2,4-dionato) (CNacac) metal complex, [M(CNacac)(2)], which acts as both a metal-ion-like and a ligand-like building unit, forms supramolecular structures by self-assembly. Co-grinding of the metal acetates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) with CNacacH formed a CNacac complex in all cases: mononuclear complex was formed in the cases of Mn(II), Cu(II) and Zn(II), whereas polymeric ones were formed in the cases of Fe(II), Co(II) and Ni(II). Subsequent annealing converted the mononuclear complexes of Mn(II), Cu(II) and Zn(II) to their corresponding polymers as a result of dehydration of the mononuclear complexes. The resultant Mn(II), Fe(II), Co(II), Ni(II) and Zn(II) polymeric complexes had a common 3 D structure with high thermal stability. In the case of Cu(II), a 1 D polymer was obtained. The Mn(II), Cu(II) and Zn(II) polymeric complexes returned to their original mononuclear complexes on exposure to water vapour but they reverted to the polymeric complexes by re-annealing. Co-grinding of metal chlorides with CNacacH and annealing of the mononuclear CNacac complexes prepared from solution reactions were also examined for comparison. [Mn(CNacac)(2)(H(2)O)(2)], [M(CNacac)(2)(H(2)O)] (M=Cu(II) and Zn(II)) and [M(CNacac)(2)](infinity) (M=Mn(II), Fe(II) and Zn(II)) are new compounds, which clearly indicated the power of the combined mechanochemical/annealing method for the synthesis of varied metal coordination complexes.  相似文献   

8.
A method has been developed for the group concentration of microamounts of metals (Fe, Co, Ni, Mn, Cu, Zn, Cd, Hg, Pb, Bi, Sb, Mo, W, V, Cr, Ga, In, Sn, Ag, Au, Pd, Pt) in the form of their 8-mercaptoquinolinates co-precipitated on bis(8-quinolyl) disulphide as collector, the latter being an oxidation product of 8-mercaptoquinoline. The collector is formed during the co-precipitation process, which is the reason for its high co-precipitating power. The elements thus concentrated are determined by atomic-absorption spectrometry after dissolution of the precipitate in dilute nitric acid.  相似文献   

9.
Conditions for the preparation of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) 3-methyladipates were investigated and their qualitative composition and magnetic moments were determined. The IR spectra and powder diffraction patterns of the complexes prepared of the general formula M(C7H10O4nH2O (n=0-11) were recorded and their thermal decomposition in air were studied. During heating the hydrated complexes are dehydrated in one (Co, Ni) or two steps (Mn, Zn) losing all crystallization water molecules (Co, Ni) or some water molecules (Mn, Zn) and then anhydrous (Co, Ni, Cu) or hydrated complexes (Mn, Zn) decompose directly to oxides (Mn, Co, Zn) or with intermediate formation the mixture of M+MO (Ni, Cu). The carboxylate groups are bidentate (Mn, Co, Ni, Cu) or monodentate (Zn). The complexes exist as polymers. The magnetic moments for the paramagnetic complexes of Mn(II), Co(II), Ni(II) and Cu(II) attain values 5.48, 4.49, 2.84 and 1.45 B.M., respectively. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

10.
The complexes formed by the simplest amino acid, glycine, with different bare and hydrated metal ions (Mn(2+), Fe(2+), Co(2+), Ni(2+), Cu(2+), Zn(2+)) were studied in the gas phase and in solvent in order to give better insight into the field of the metal ion-biological ligand interactions. The effects of the size and charge of each cation on the organization of the surrounding water molecules were analyzed. Results in the gas phase showed that the zwitterion of glycine is the form present in the most stable complexes of all ions and that it usually gives rise to an eta(2)O,O coordination type. After the addition of solvation sphere, a resulting octahedral arrangement was found around Ni(2+), Co(2+), and Fe(2+), ions in their high-spin states, whereas the bipyramidal-trigonal (Mn(2+) and Zn(2+)) or square-pyramidal (Cu(2+)) geometries were observed for the other metal species, according to glycine behaves as bi- or monodentate ligand. Despite the fact that the zwitterionic structure is in the ground conformation in solution, its complexes in water are less stable than those obtained from the canonical form. Binding energy values decrease in the order Cu(2+) > Ni(2+) > Zn(2+) approximately Co(2+) > Fe(2+) > Mn(2+) and Cu(2+) > Ni(2+) > Mn(2+) approximately Zn(2+) > Fe(2+) > Co(2+) for M(2+)-Gly and Gly-M(2+) (H(2)O)(n) complexes, respectively. The nature of the metal ion-ligand bonds was examined by using natural bond order and charge decomposition analyses.  相似文献   

11.
Zusammenfassung Es werden zwei Verfahren zur Spurenanalyse von Reinstaluminium beschrieben, bei welchen die zu bestimmenden Spuren durch Fällung mit Spurenfängern von Aluminium getrennt werden. Beim Verfahren I werden mit Thioacetamid in natronalkalischer Lösung Cd, Co, Cu, Fe, Mn, Ni, Pb und Zn als Sulfide Ca, Cr, Mg und Ti als Hydroxyde gefällt. Als Spurenfänger wird Thallium zugesetzt. Verfahren II bedient sich der Fällung von Cd, Co, Cu, Fe, Ga, Mo, Ni, Sb, Sn, V und Zn (sowie Cr, Mn, Pb, Ti teilweise) mit Ammoniumpyrrolidindithiocarbaminat und Thionalid in essigsaurer Lösung, ebenfalls mit Thallium als Spurenfänger. Die Spurenkonzentrate werden mit Bezugselementen versehen, auf Kohle-bzw. Graphitelektroden aufgetrocknet und im Feussner-Funken spektralanalytisch untersucht. Bei einer Ausgangsmenge von 1 g Reinstaluminium können die genannten Elemente ihrer spektralanalytischen Empfindlichkeit entsprechend in Konzentrationen von 0,01–0,00001% bestimmt werden.  相似文献   

12.
The hydrogen chemical ionization (H2 CI) mass spectra of a range of metal(II) (Ni, Cu, Co, Pt), metal (III) (Al, Mn, Ga, Fe (bearing a single axial ligand)) and metal(IV) (Si, Ge, Sn (bearing two axial ligands) and V (as V?O2+)) porphyrins have been determined, The spectra are highly dependent on the coordinated metal, rather than the axial ligand(s) (where present). Ni(II), Cu(II), Mn(II or III), Ga(III), Ge(IV), Fe(III) and Sn(IV) porphyrins fragment via hydrogenation and demetallation, followed by cleavage of the resulting porphyrinogens at the meso(bridge) positions to give mono- and di-pyrrolic fragments. Tripyrrolic fragments are also observed in the case of Ni(II), Cu(II) and Sn(IV). Fragmentations of this type are similar to those observed for free-base porphyrins. In the case of Pt(II), Co(II), Al(III), Si(IV) and V(IV) (as vanadyl), the dipyrrolic fragment ions are either very weak or completely absent; hence their H2CI spectra contain limited structural information. This variable CI behaviour may be related to the relative stabilities of the metalloporphyrins together with the multiple stable valency states exhibited by several metals.  相似文献   

13.
The extraction of the following metals from aqueous solutions containing excess bromide with methyl ethyl ketone (MEK), and methyl isobutyl ketone MIBK has been investigated:—Cu(I), Cu(II), Zn(II), Ni(II), Co(II), Fe(II), Fe(III), Al(III), Mn(II), Sn(II) and Sn(IV). The use of MEK was found to be strictly limited by its solubility in acidic aqueous solutions. Determinations of the formulae of the extracted compounds were attempted in two cases but were found to be not wholly satisfactory and were discontinued. An interesting reaction between the cupric bromide complex and the solvents was noticed. Separations of Fe(IIl) from Mn(II), Fe(III) from Al(III), Fe(III) from Co(Il) and Fe(III) from Ni(II) could be achieved under suitable conditions.  相似文献   

14.
《Analytical letters》2012,45(5):413-422
Abstract

The stepwise metal-ligand stability constants of tetracycline and oxytetraoycline chelates with Mg(II), Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II), Cu(II), Zn(II), Zr(II) and Sn(II) have been determined using the Bjerrum-Calvin titration technique as employed by Irving and Rossotti. Protonation constant of the ligand and stability constants of the respective metal complexes have been determined at constant temperature (25°C) and ionic strength (0.1 M KCl). The general order of overall stability constant values have been found to be: Zr(IV) > Fe(III) > Co(II) > Zn(II) > Mg(II) > Mn(II) > Ni(II) > Sn(II) > Tn(II) > Cr(II). The rign values of the atability constanta are attricutel to the Ligands, which are stronger as an acid and weaser as a oase.  相似文献   

15.
Donaldson EM  Mark E 《Talanta》1982,29(8):663-669
The chloroform extraction of 30 elements (Fe, Co, Ni, Zn, Cd, Ge, Sn, V, As, Sb, Bi, Cu, Ag, Au, Mn, Re, Ga, In, Tl, Se, Te, Cr, Mo, U, Pt, Pd, Rh, Ir, Ru and Ce) from 0.1-8M sulphuric acid in the presence of potassium ethyl xanthate has been studied. Pd(II), Bi, As(III), Sb(III), Se(IV) and Te(IV) are completely extracted and Au(III) is largely extracted over the range of acid concentration investigated. Fe(II), Tl(I), Rh(III) and Cr(VI) are only slightly extracted and Se(VI), Te(VI), Ru(III), Cr(III), Mn(II), Zn, Ce(IV), Ir(IV) and Ge(IV) are not extracted at all. Depending on the acid concentration, the remaining elements are all partly extracted. Results are compared with those obtained in an earlier study of the extraction of xanthate complexes from hydrochloric acid media. The processes involved in the formation of some xanthate complexes and potential analytical separations are discussed.  相似文献   

16.
Thiodibenzoylmethane is a suitable reagent for the extraction and photometric determination of traces of cadmium. There is no interference from 10000-fold amounts of alkaline and alkaline earth metals, B, Al, Ga, In, Mn, Fe, Cr, and from 1000-fold amounts of As, Sb, Sn, Pb, Bi, Cu, Co, Ni, Pd; Ag, Hg, Tl and Zn are tolerated up to a 100-fold excess. The proposed method is compared with various other possibilities for cadmium determinations.  相似文献   

17.
In an effort to better understand the antiproliferative effects of the tridentate hydrazone chelators di-2-pyridyl ketone isonicotinoyl hydrazone (HPKIH) and di-2-pyridyl ketone benzoyl hydrazone (HPKBH), we report the coordination chemistry of these ligands with the divalent metal ions, Mn, Co, Ni, Cu, and Zn. These complexes are compared with their Fe(II) analogues which were reported previously. The crystal structures of Co(PKIH)(2), Ni(PKIH)(2), Cu(PKIH)(2), Mn(PKBH)(2), Ni(PKBH)(2), Cu(PKBH)(2), and Zn(PKBH)(2) are reported where similar bis-tridenate coordination modes of the ligands are defined. In pure DMF, all complexes except the Zn(II) compounds exhibit metal-centered M(III/II) (Mn, Fe, Co, Ni) or M(II/I) (Cu) redox processes. All complexes show ligand-centered reductions at low potential. Electrochemistry in a mixed water/DMF solvent only elicited metal-centered responses from the Co and Fe complexes. Remarkably, all complexes show antiproliferative activity against the SK-N-MC neuroepithelioma cell line similar to (HPKIH) or significantly greater than that of the (HPKBH) ligand which suggests a mechanism that does not only involve the redox activity of these complexes. In fact, we suggest that the complexes act as lipophilic transport shuttles that allow entrance to the cell and enable the delivery of both the ligand and metal which act in concert to inhibit proliferation.  相似文献   

18.
Résumé On décrit la détermination de traces dans le germanium, le silicium et le sélénium. En appliquant des techniques gamma spectrométriques, précédées ou non de séparations chimiques il est possible de doser les éléments suivants dans (1) germanium: As, Cu, Au, Ga, Zn, Hg, Cr, Sn, Sb, Co, In, Ni, Ir, Se, Sc, Ag, Ta, Hf et U; (2) silicium: P, Au, Sb, Ga, Fe, K, Cr, Mo, Sn, As, Co, In, Zn, Cu, W, Ta, Na, Eu, Sm, La, Sc et T1; (3) sélénium: Cl, Br, I, P, S, Te, Na, K, Cr, Fe, Co, Cu, Zn, Ga, Sc, Ag, Cd, La, W, Au et Tl. Les concentrations et ou limites de détections varient de quelques parties par million à 10−3 parties par milliard.  相似文献   

19.
A compartment ligand 2,6-bis[5′-chloro-3′-phenyl-1H-indole-2′-carboxamidyliminomethyl]-4-methylphenol was prepared and homobinuclear phenol-bridged Cu(II), Ni(II), Co(II), Zn(II), Cd(II), Hg(II), Fe(III), and Mn(II) complexes have been prepared by the template method using the precursors 2,6-diformyl-4-methylphenol, 5-chloro-3-phenylindole-2-carbohydrazide and metal chlorides in 1 : 2 : 2 ratio, respectively. The complexes were characterized by elemental analyses, conductivity measurements, magnetic susceptibility data, IR, NMR, FAB mass and ESR spectra, TGA, and powder XRD data. Cu(II), Co(II), Zn(II), Cd(II) and Hg(II) complexes exhibit square pyramidal geometry whereas Ni(II), Mn(II), and Fe(III) complexes are octahedral. Low magnetic moment values for Cu(II), Ni(II), Co(II), Fe(III), and Mn(II) complexes show antiferromagnetic spin-exchange interaction between two metal centers in binuclear complexes. The ligand and its complexes were tested for antibacterial activity against Escherichia coli and Staphyloccocus aureus, and antifungal activity against Aspergillus niger and Candida albicans.  相似文献   

20.
The use of inductively coupled plasma mass spectrometry (ICP-MS) for the determination of trace elements in Al2O3 powders is reported. Special interest is given to a preconcentration of the trace elements by on-line coupling of chromatography to ICP-MS. This is based on the complexation of Co, Cu, Cr, Fe, Ga, Mn, Ni, V and Zn with hexamethylene-dithiocarbamate (HMDC), their preconcentration on a C18 RP column by reversed phase liquid chromatography and their elution with CH3OH-H2O mixtures. A direct coupling of the HPLC system to the ICP-MS has been realized by high pressure pneumatic nebulization using desolvation. With the Chromatographie method developed, removal of the AI by at least 99% was achieved. For the trace elements V, Fe, Ni, Co, Cu and Ga, high and reproducible recoveries (ranging from 96–99%) were reached. The method developed has been shown to considerably enhance the power of detection as compared with direct procedures, namely down to 0.02–0.16 ( for V and Fe, respectively. The possibilities of the method are shown by the determinations of V, Mn, Fe, Ni, Co, Cu, Zn and Ga at the μg/g level in A12O3 powders. The accuracy of the method at the 0.06 to 9.0 level for Co and Fe, respectively, is demonstrated by a comparison with results of independent methods from the literature.  相似文献   

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