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1.
Summary The quantitative determination of trace elements in human blood serum by Total Reflection X-Ray Fluorescence Analysis (TXRF) is influenced by absorption- and reflection-effects caused by the organic (proteins) and inorganic (P, S, Na, K, Ca, Cl) matrices. To minimize these effects we have developed a sample preparation technique based on the decomposition of the organic matrix and followed by the separation of the trace elements from the organic matrix by ion-exchange. The described method enables the simultaneous determination of K (1584 g), Ca (666 g), Fe (22 g), Cu (9.6 g), Zn (8.8 g), Se (0.97 g), Sn (1.3 g), Pb (0.12 g) and Rb (1.6 g) (obtained values in parentheses).
Herrn Prof. Dr. G. Tölg zum 60. Geburtstag gewidmet 相似文献
Herrn Prof. Dr. G. Tölg zum 60. Geburtstag gewidmet 相似文献
2.
Zusammenfassung Ein schnelles und einfaches Mikroverfahren zum Nachweis einiger Heteroatome organischer Verbindungen wurde entwickelt. Nach Aufschluß mit metallischem Kalium werden die entstehenden Ionen mit der Ringofenmethode getrennt und mit empfindlichen Reaktionen nachgewiesen. Nachweisgrenze: 0,5 bis 1g Stickstoff, 1 bis 2g Schwefel, 2 bis 3g Jod, 4 bis 5g Brom, 5 bis 10g Chlor in 0,5 bis 1 mg Einwaage.
Summary A rapid and simple micromethod was developed for the detection of several hetero-elements in organic compounds. After breaking down the sample with metallic potassium, the resulting ions are separated by the ring oven method and detected by means of sensitive reagents. Detection limits: 0.5 to 1g nitrogen, 1 to 2g sulfur, 2 to 3g iodine, 4 to 5g bromine, 5 to 10g chlorine in samples weighing 0.5 to 1 mg.
Résumé On a découvert un procédé à l'échelle micro, simple et rapide, pour rechercher certains hétéroéléments dans les composés organiques. Après mise en solution par le potassium métallique, on sépare les ions formés suivant la méthode du four annulaire et l'on effectue la recherche au moyen de réactions sensibles. Limite de dilution: 0,5 à 1g d'azote, 1 àg de soufre, 2 àg d'iode, 5 à 10g de chlore sur 0,5 à 1 mg de prise d'essai.相似文献
3.
Toshihide Saito Kunishige Higashi Kazuyoshi Hagiwara 《Fresenius' Journal of Analytical Chemistry》1982,313(1):21-23
Summary For the trace determination of sodium alkylbenzenesulphonate (ABS) by HPLC the following conditions were employed: Shimadzu ZORBAX SIL Column (5 m, 4.6 mm i.d. x 150 mm) as stationary phase, 0.2% ammoniaethanol (v/v) as mobile phase, UV detector at 225 nm, injection volume 12 l. The chromatograms of ABS were simple and sharp (detection limit of ABS 0.02 g in 12 l of ethanol). The calibration curves of ABS were linear in a concentration range of 0.03 0.3 g in 12 l of ethanol. In the case of linear sodium dodecylbenzenesulphonate positive errors of 1 4% were caused by non-ionic surfactants or laurylsulphate (6 times excess), 10 50% positive errors were caused by 2 6 times excess of household detergents.Standard water samples containing ABS were treated with a weak base anion-exchange resin, the adsorbed ABS were eluted, and then determined either by HPLC or by the methylene blue spectrophotometric method. Recoveries of ABS in water were about 92 107% by HPLC.
Bestimmung von Spuren Natriumalkylbenzolsulfonat mit Hilfe der HPLC. Anwendung auf Wasser
Zusammenfassung Für die Spurenbestimmung von Natriumalkylbenzolsulfonat (ABS) durch HPLC werden die folgenden Bedingungen empfohlen:Shimadzu ZORBAX SIL (5 m, 4,6 mm x 150 mm) als stationäre Phase, 0,2% Ammoniak/Ethanol als mobile Phase, UV-Detektor bei 225 nm, Injektionsvolumen 12 l. Die erhaltenen Chromatogramme sind einfach und scharf (Nachweisgrenze 0,02 g in 12 ml Ethanol). Die Eichkurven sind im Konzentrationsbereich von 0,03–0,3 g in 12 l Ethanol linear. Im Falle des linearen Natriumdodecylbenzolsulfonats werden bei Anwesenheit von nicht-ionischen oberflächenaktiven Substanzen oder von Laurylsulfat in 6fachem Überschuß positiver Fehler von 1–4% erhalten; bei 2–6fachem Überschuß von Haushaltswaschmitteln ergeben sich positive Fehler von 10–50%.Standard-Wasserproben werden zunächst einer Behandlung mit einem Anionenaustauscher unterzogen, die adsorbierten ABS eluiert und durch HPLC oder nach der Methylenblaumethode analysiert. Wiederfindungsraten liegen bei 92–107%.相似文献
4.
Jürgen Reiß 《Fresenius' Journal of Analytical Chemistry》1978,293(2):138-140
Summary Spots of citrinin, ochratoxin A, aflatoxin M1 and penicillic acid on thin-layer chromatograms can be semi-quantitatively estimated by using a grey scale, commonly used in photo laboratories. The detection limits are 0.01 g for citrinin, 0.006 g for ochratoxin A, 0.002 g for aflatoxin M1 and 0.01 g for penicillic acid. Standard curves for these mycotoxins are given.
Halbquantitative Bestimmung der Mycotoxine Citrinin, Ochratoxin A, Aflatoxin M1 und Penicillinsäure auf Dünnschicht-Chromatogrammen mit Hilfe eines Graukeils
Zusammenfassung Mit Hilfe eines in Photolabors gebräuchlichen Graukeils können dünnschicht-chromatographische Flecke der obengenannten Mycotoxine halbquantitativ bestimmt werden. Die Nachweisgrenzen betragen 0,01 g für Citrinin, 0,006 g für Ochratoxin A, 0,002 g für Aflatoxin M1 und 0,01 g für Penicillinsäure. Eichkurven werden angegeben.相似文献
5.
L. Nitschke R. Müller G. Metzner L. Huber 《Fresenius' Journal of Analytical Chemistry》1992,342(9):711-713
Summary A simple and fast determination of trace amounts of commercially used cationic surfactants is described. After extraction from water cationic surfactants are separated by HPLC and detected by conductometry. The detection limit is 3 g/l for distearyldimethylammonium chloride, 16 g/l for ditallowimidazolinium methosulphate, and 6 g/l for dodecylpyridinium chloride. 相似文献
6.
U. M. Kasar A. R. Joshi S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1984,81(1):109-115
Fluoride and sulphate complexing of Np(VI) has been studied by controlled-potential coulometry at a constant ionic strength. The values of
1
*
and
2
*
for fluoride complexes were found to be 9.4 and 8.9, respectively, at an ionic strength =0.5. At an ionic strength =1.0,
1
*
and
2
*
obtained were 6.6 and 10.5, respectively. Sulphate complexing of Np(VI) was studied only at an ionic strength =0.5. The value of
1
*
obtained was 5.6. 相似文献
7.
Diphenylphosphine oxidatively adds to the ReRe bonds of Re2
X
4(-dppm)2 (X=Cl or Br; dppm=Ph2PCH2PPh2) and Re2Cl4(-dpam)2 (dpam=Ph2AsCH2AsPh2) to afford the dirhenium(III) complexes Re2(-X)(-PPh2)HX
3(-LL)2. The dppm complexes have also been prepared from the reactions of Re2(-O2CCH3)X
4(-dppm)2 with Ph2PH, and a similar strategy has been used to prepare Re2(-Cl)(-PPh2)HCl3(-dmpm)2 (dmpm=Me2PCH2PMe2) from Re2(-O2CCH3)Cl4(dmpm)2. Phenylphosphine likewise reacts with Re2
X
4(-dppm)2 to give Re2(-X)(-PHPh)HX
3(-dppm)2. An X-ray crystal structure determination on Re2(-Cl)(-PPh2)HCl3(-dppm)2 confirms its edge-shared bioctahedral structure. This complex crystallizes in the space group
(No. 148) witha=21.699(3) Å, =84.50(4)°,V=10084(5) Å3, andZ=6. The structure was refined toR=0.049 (R
w
0.069) for 5770 data withI>3.0(I). The Re-Re distance is 2.5918(7) Å. Oxidation of the bromide complex Re2(-Br)(-PPh2)HBr3(-dppm)2 with NOPF6 produces the unusual dirhenium(III, II) cation [Re2(-H)(-Br)[P(O)Ph2]Br2(NO)(-dppm)2]+ which has been structurally characterized as its perrhenate salt, [Re2(-H)(-Br)[P(O)Ph2]Br2(NO)(-dppm)2]ReO4 · 2CH2Cl2. This complex crystallizes in the space group
(No. 2) witha=14.187(7) Å,b=16.419(5) Å,c=16.729(5) Å, =98.76(2)°, =110.11(3)°, =104.66(3)°,V=3414(6) Å3,Z=2. The structure was refined toR=0.040 (R
w
=0.051) for 5736 data withI>3.0(I). The presence of a phosphorus-bound [P(O)Ph2]– ligand, a linear nitrosyl and a bridging hydrido ligand has been confirmed. The Re-Re distance is 2.6273(8) Å. 相似文献
8.
V. P. Guinn L. Nakazawa Dahlgren J. C. Leslie 《Journal of Radioanalytical and Nuclear Chemistry》1984,84(1):103-108
The instrumental neutron activation analysis (INAA) Advance Prediction Computer Program (APCP) is described, as well as its areas of usefulness. Particular attention is devoted to its ability to predict g and ppm INAA lower limits of detection (LOD's) of any particular elements of interest in any sample matrix type of even very approximately known average or typical elemental composition. In general, INAA g LOD's are found to be 10 to 100 times higher than the corresponding interference-free values, and INAA ppm LOD's are found to be 100 to even 100 000 times higher than the corresponding interference-free values calculated for a one-gram sample. 相似文献
9.
H. Berge und H. Mennenga 《Fresenius' Journal of Analytical Chemistry》1965,213(5):346-349
Zusammenfassung N,N'-Bis-(o-ammobenzyliden)-äthylendiamin (ABAD) bildet mit Ni2+ und Co3+ stabile Chelate, wobei schon durch Luftsauerstoff eine Oxydation von CoIIzu CoIII-ABAD erfolgt. Ni-ABAD kann quantitativ mit Benzol extrahiert und spektrophotometrisch bei 486 nm bestimmt werden. CoIII-ABAD wird in der wäßrigen Schicht bei 430 nm bestimmt. Die Grenzkonzentrationen betragen 0,5 g Ni/ml und 0,6 g Co/ml in Konzentrationsverhältnissen von 1001 bis 1100. Die Methode ist ebenfalls zur quantitativen Bestimmung von Co neben Cu geeignet.
Summary N,N'-Bis-(o-aminobenzylidene)-ethylenediamine (ABAD) quantitatively reacts with Ni2+ and Co3+ to form stable chelates. CoII-ABAD is easily oxidised by air to CoIII-ABAD. Ni-ABAD can be extracted with benzene and determined spectrophotometrically at 486 nm, CoIII-ABAD is determined in the water-layer at 430 nm. The limit of detection is 0.5 g Ni/ml and 0.6 g Co/ml by the ratio from 1001 to 1100. The method is also suitable for separation and determination of Co in the presence of Cu.相似文献
10.
H. F. R. Reijnders P. Quevauviller D. Van Renterghem B. Griepink H. van der Jagt 《Fresenius' Journal of Analytical Chemistry》1994,348(7):439-444
Analyses of rainwater are routinely performed by a number of organisations to monitor the contribution from rainwater to the component occurrences in the environment and the acidification of the environment. To control the quality of such determinations, the Community Bureau of Reference (BCR) has organised a certification campaign to produce two simulated rainwater reference materials (CRM 408, low mineral content and CRM 409, high mineral content). The materials were carefully prepared (addition of pro analysis and supra pure reagents with the mentioned elements to silica-free deionised water) and its homogeneity and long-term stability were verified. The materials were certified for their contents of ammonium (106 mol/kg) (CRM 409), calcium (7.68 and 15.5 mol/kg), chloride (67.3 and 113 mol/kg), hydronium (16.6 and 48.0 mol/kg), magnesium (6.14 and 12.3 mol/kg), nitrate (20.1 and 78.1 mol/kg), potassium (4.25 mol/kg) (CRM 409), sodium (42.0 and 82.9 mol/kg) and sulphate (10.5 and 53.2 mol/kg). Indicative values (not certified) are given for ammonium and potassium in CRM 408. This paper presents the certification work performed, as well as the analytical work for the certification of the contents of relevant species. 相似文献
11.
V. A. Maksakov V. P. Kirin V. A. Ershova S. V. Tkachev P. P. Semyannikov 《Russian Chemical Bulletin》1993,42(11):1898-1901
The reactions of cysteine ethyl ester with a series of triosmium clusters have been studied. Enantiomeric (-H)Os3{-SCH2CH(CO2Et)NH2}(CO)10 and diastereomeric (-H)Os3{-2-SCH2CH(CO2Et)NH2}(CO)9 forms of the optically active cluster complexes have been obtained. Diastereomeric clusters have been separated by TLC on Silufol plates. The treatment of the enantiomeric complex (-H)Os3{-SCH2CH(CO2Et)NH2}(CO)10 with the trimethylamine oxide yields the diastereomeric pair (-H)Os3{-2-SCH2CH(CO2Et)NH2}(CO)9. The structures of the complexes obtained have been established on the basis of IR,1H NMR and mass spectrometry as well as X-ray analysis data.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1981–1984, November, 1993. 相似文献
12.
Chemical oscillatory behavior in the uncatalyzed bromate oxidation of hydroquinone and nitrophenols is reported. The reaction is strongly inhibited by stirring. Effect of one-electron redox couples (EZ catalysts) on the system is described.
. . - ( EZ) .相似文献
13.
Uranium shows relatively conservative behaviour in seawater because of the formation of stable carbonato complexes, whereas particulate uranium, involved in suspended particles with the particle size of more than 0.45 m, is a minor constituent. It was found that particulate uranium, with a range from 0.24 to 39 Bq·1–1, varies spatially and temporally. Its highest concentration occurs in the tropical region of the western North Pacific during the winter of 1983, corresponding to the 1983 El Nifio event. A leaching experiment revealed that major species of particulate uranium are labile organic complexes. Mass balance considerations suggest that particulate uranium in open ocean waters correlates with the presence of particulate organic matter (POM). A high peak of particulate uranium in 1983 may indicate that POM, i.e., primary productivity, increased in the western tropical Pacific during the El Niño event. 相似文献
14.
Furusawa N 《Analytical and bioanalytical chemistry》2004,378(8):2004-2007
A method for the determination of aldrin, dieldrin, DDT, DDE, and DDD contamination in animal fats (beef tallow, lard, and chicken fat) without using toxic reagents is developed, that uses high-performance liquid chromatography after the sample has been prepared by matrix solid-phase dispersion (MSPD) with acidic alumina oxide. A reversed-phase C1-silica column with a mobile phase of 50% (v/v) ethanol solution (in water) and a photo-diode array detector were used for the determination. Average recoveries of the target compounds (0.2–5.0 g g–1) ranged from 84–98%, with coefficients of variation of <5%. The limits of quantitation were 0.16 g g–1 for AD, 0.10 g g–1 for DD, 0.06 g g–1 for DDT, 0.07 g g–1 for DDE, and 0.05 g g–1 for DDD. No toxic reagents were used at all. 相似文献
15.
The effect of various inorganic polymers on the catalytic activity and selectivity of platinum in the hydrogenation of 4-chloronitrobenzene and dinitrotoluene has been studied. Platinized iron-containing polycyanogens are less active but more selective catalysts for the hydrogenation of 4-chloronitrobenzene than Pt/C or Pt/BaSO4.
4- . , , , 4-, Pt/C Pt/BaSO4.相似文献
16.
F. Y. Iskander 《Journal of Radioanalytical and Nuclear Chemistry》1995,201(5):401-408
Instrumental neutron activation analysis was used to measure the concentrations of 24 elements in four honey brands commercially available in Austin, Texas (USA). The measured elements (and concentration) were: As, (<30 ng/g); Ba, (<2 g/g); Br, (0.24–0.49 g/g); Ce, (<20 ng/g); Co, (9–180 ng/g); Cr, (37–64 ng/g); Cs, (<3–45 ng/g); Fe, (<4–15.9 g/g); Hf, (<3 ng/g); Hg, (1 ng/g); K, (91–230 g/g); La, (<4 ng/g); Na, (20.3–25.3 g/g); Ni, (0.39–0.77 g/g); Rb, (68–340 ng/g); Sb, (13–61 ng/g); Sc, (<0.3–200 ng/g); Se, (<20 ng/g); Sm, (<9 ng/g); Sr, (<2 ng/g); Th, (<4 ng/g); U, (<30 ng/g); Zn, (3.36–4.61 g/g); and Zr, (<0.5–0.84 g/g). The results obtained were compared to the concentration of the same elements in honey produced or commercially available in Turkey, Mexico, El-Salvador, China, Czechoslovakia and Yugoslavia. 相似文献
17.
A. Grünert und K. H. Bäßler 《Fresenius' Journal of Analytical Chemistry》1973,267(5):342-346
Zusammenfassung Für die im Plasma an Albumin gebundenen sog. freien Fettsäuren (FFS) wird ein neues gas-chromatographisches Analysenverfahren vorgestellt. Das Probenvolumen beträgt 50 l Serum oder Plasma. Die Extraktion erfolgt in 1,1 ml CHCl3/CH3OH (21, v/v) mit n-Heptadecansäure als innerem Standard (0,05 Val C170/ml). Nach Eindampfen am Rotationsverdampfer werden die FFS im verschlossenen Reaktionskölbchen mit 20 l CH3J/Essigsäureäthylester (11, v/v) über festem K2CO3 bei 90°C 1 h verestert. Die Varianz des Verfahrens errechnet sich bei 15 Parallelbestimmungen zu 4,85%.Vortrag anläßlich der Tagung Spurenanalyse, 2. bis 5. April 1973 in Erlangen. 相似文献
18.
Summary Solochrome Black 6 BN in an acetate buffered medium containing methanol reacts with U(IV) to give a blue complex which permits photometric determination with 5g U/ml to 100g U/ml.In the presence of zinc acetate, uranyl ion also may be spectrophotometrically determined by means of the same dye. From 2g U/ml to 40g U/ml may be determined with a relative error of less than ± 0.05.
Zusammenfassung Es werden zwei Methoden zur spektrophotometrischen Bestimmung von Uran mittels Solochromschwarz 6 BN beschrieben. Dieser Farbstoff bildet mit U(IV) in acetatgepuffertem, methanolhältigem Medium einen blaugefärbten Komplex, der die Bestimmung von 5 bis 100g U/ml erlaubt.Mit demselben Farbstoff lassen sich auch 2 bis 40g U/ml in Lösungen von Uranylchlorid bestimmen.
Résumé Le noir solochrome 6 BN en milieu tampon acétique contenant du méthanol réagit avec U-IV en donnant un complexe bleu qui permet le dosage photométrique de 5 g U/ml à 100 g U/ml.En présence d'acétate de zinc, on peut aussi doser l'ion uranyle par spectrophotométrie avec le même colorant. On peut doser de 2 g U/ml à 40 g U/ml avec une erreur relative inférieure à ± 0,05.相似文献
19.
The interaction of propylene with gallium oxide has been studied by the MINDO-3 method using a cluster model. It is shown that the energy barrier against allyl C–H bond dissociation is mainly determined by the Coulomb repulsion between the molecule and the central metal ion. Interaction of the dissociating hydrogen with the oxygen of the fragment ensures the stabilization of the system.
MINDO-3 і . , C–H , , . і .相似文献
20.
J. Simon 《Journal of Thermal Analysis and Calorimetry》1972,4(1):205-214
The determination of water content by means of the Derivatograph is treated in the paper. The determination of water in analytical precipitates, various pharmaceutical products, biological substances, the products of food industry is treated on the basis of some practical examples. The applicability of the Derivatograph for determining the adsorption capacity of industrial adsorbents, the hydration conditions of cement, the system Ca3A-CaSO4 · H2O and the rehydrability of clay minerals is demonstrated. The aluminium oxide barrier layers were investigated on the basis of the water content of the aluminium hydroxide. For the characterization of the different strengths by which water is bound in strontium chloride hydrates the apparent activation energies are also presented.
Zusammenfassung Die Bestimmung von Wasser mit Hilfe des Derivatographen wurde besprochen. Es wurden die verschiedenen Anwendungsmöglichkeiten der Methode, wie die Bestimmung des Wassers in analytischen Niederschlägen, Arzeneimitteln, Lebensmittel, biologischen Substanzen an Beispielen besprochen. Die Anwendbarkeit des Derivatographen zur Bestimmung der Adsorptionskapazität von industriellen Adsorbenten, der Hydrationsverhältnisse von Zement, des Systems Ca3A-CaSO4 · H2O und der Rehydration von Tonmineralien wurde erörtert. Aluminiumoxydgrenzschichten konnten auf Grund des Wassergehalts des Aluminiumhydroxyds geprüft werden. Zur Charakterisierung der verschiedenen wasserbindenden Kräfte werden die Werte der scheinbaren Aktivierungsenergien der Alkalierdchlorid-hydrate vorgelegt.
Résumé L'article traite de la détermination de la teneur en eau à l'aide du Derivatograph. La méthode est exposée en se servant d'exemples pratiques comme les précipités analytiques, divers produits pharmaceutiques, alimentaires, des substances biologiques. On montre que le Derivatograph peut être utilisé pour déterminer la capacité d'adsorption des adsorbants industriels, pour examiner l'hydration du ciment, du' système Ca3A-CaSO4 · H2O et la rehydration des minéraux argileux. Examination des couches interfaces d'oxyde d'aluminium sur Ja base de la teneur en eau du hydroxide d'aluminium. L'énergie d'activation apparente a été déterminée et utilisée pour caractériser les différentes forces de liaison de l'eau dans les chlorures alcalino-terreux hydratés.
, .相似文献