Odd-Excited Binomial States of the Radiation Field and Some of Their Statistical Properties

In this paper a new state called odd-excited binomial state (OEBS) is introduced. It interpolates between the odd number state and the odd-excited coherent state. We discuss some statistical properties, such as the Glauber second-order correlation function and squeezing phenomenon (normal and amplitude-squared squeezing) for this state. The quasiprobability distribution functions (Husimi Q-function and Wigner W-function) are also examined.     

Ca(NO3)2•4H2O-catalysed Biginelli Reaction: One-pot Synthesis of 1,2,3,4-Tetrahydropyrimidin-2-ones/pyrimidine-2-thiones under Solvent-free Conditions

The synthesis of 1,2,3,4-dihydropyrimidinone/thione derivatives was achieved in good to excellent yields using calcium(II) nitrate as catalyst to promote the Biginelli three-component condensation reaction from a diversity of aromatic aldehydes, β-keto compounds and urea or thiourea. The reaction was carried out under solvent-free conditions.     

Study of the dehydration of Portland Cement by Mössbauer spectrometry

Egyptian Portland Cement in the form of one inch cube was hydrated at different times of hydration. Nine cubes of each period of hydration were heated for five minutes 200, 300, 400 up to 1000°C then were quenched in air. The compressive strength was measured for these samples and related to unheated ones. These cubes were ground and measured by Mössbauer spectrometry to correlate the effect of dehydration of cement pastes on the states of iron, with the decrease of compressive strength. It was observed that starting from 400°C the central doublet characteristic of the hydration process decreased as the dehydration temperature was increased. At 1000°C the dehydration process was complete, the central doublet disappeared and the compressive strength vanished. The hydration process was found to be reversible. The application of Mössbauer spectrometry to estimate the degree of fire in concrete building was demonstrated.     

Reactions of copper acetylides. Structure of (π-C5H5)Ru(PPh3)2 (CCPh)CuCl,and new syntheses of transition metal cluster compounds

In contrast to a related iron—copper compound, the complex (π-C₅H₅)Ru(PPh₃)₂(C₂Ph)CuCl is shown to be monomeric, and contains linear dicoordinate copper(I); the reactions of this and similar complexes with metal carbonyls are sources of new mixed-metal clusters, such as (π-C₅H₅)Fe₂ Ru(C₂Ph)(CO)₆ (PPh₃).     

Solid reactions in Rubidium Carbonate-Vanadium Pentoxide system

The reactions between rubidium carbonate and vanadium pentoxide were performed at different high temperatures. Four reaction products of the compositions: I. Rb₂O · V₂O₅; II. 2 Rb₂O · V₂O₅; III. 3 Rb₂O · V₂O₅; and IV. Rb₂O · 4 V₂O₅ were obtained. According to the determination of Rb and the X-ray powder photographs of the products the existence of rubidium metavanadate (RbVO₃) and rubidium pyrovanadate (Rb₄V₂O₇) was confirmed. On the other hand, the preparation of a pure rubidium orthovanadate (Rb₃VO₄) and rubidium tetravanadate (Rb₂O · 4 V₂O₅) was not successful. The diffraction pattern of Rb₂O · V₂O₅ obeys hexagonal indexing with lattice dimensions a = 7.347 and c = 13.608 Å.     

Subordination des résolvantes

Résumé Soit (V ₎₀ une résolvante définie sur un espace mesurable telle que le noyau initial est borné; on trouve une condition nécéssaire et suffisante pour qu'un noyau borné U possède une résolvante (U ₎₀ telle que U V pour tout 0. On donne plusieurs applications de ce résultat.     

Fluorescence monitoring of ultrasound degradation processes

Ultrasound-based water treatment is often applied for degradation of stable organic pollutants, such as polycyclic aromatic hydrocarbons and halogenated compounds. Monitoring the degradation process, during the application of ultrasound radiation, is of considerable economical interest. In this work, the possibility of performing on-line spectral analysis during sonication was examined and it was found that direct absorption or fluorescence readings are misleading. Optical monitoring is strongly affected by the absorption and scattering of light by cavitation micro-bubbles and ultrasound induced particulates. A model was developed to account for these effects and to allow for on-line fluorescence analysis. The model takes into account the absorption and scattering coefficients of the micro-bubbles and particulates, as well as their time dependent concentration. The model parameters are found from independent measurements where the pollutants are added to already sonicated pure water. Then, the model is tested for predicting the actual fluorescence behavior during the sonication process. It has been shown that the model allows for recovery of the true degradation data, as obtained by off-line HPLC measurements.     

The spectrophotometric and heterometric determination of some alkaloids as cobaltothiocyanates

Small amounts of papaverine (about 3 mg in 15 ml solution) can be determined heterometrically in the presence of thiocyanate by titration with cobaltous solution. A strong electrolyte (Na₂SO₄) must be added to obtain a clear endpoint. The titration can be carried out in the presence of large amounts (97%) of quinine and ephedrine. The titration takes 2–3 min and the error rarely exceeds 1%.Papaverine, quinine, and ephedrine can be determined individually by spectrophotometry as their cobaltothiocyanates, which are extracted in 30% cyclohexanone in carbon tetrachloride, and the optical density measured at 625 nm. The method is reproducible at milligram levels with a standard deviation of ±0.3% for papaverine and quinine and = 0.5% for ephedrine.     

Analysis of nitrate-perchlorate mixtures by difference spectrophotometry

Nitron and tetraphenylarsonium chloride react with a cobaltous salt in the presence of thiocyanate to form blue ion-association complexes, which can be extracted with organic solvents. This fact has been made the basis for the analysis of mixtures of nitrate and perchlorate by difference spectrophotometry. An aliquot of the sample solution is treated with a known excess of tetraphenylarsonium chloride to precipitate perchlorate only. After separating off the precipitate, the excess of reagent is determined in the supernatant liquid as tetraphenylarsonium cobaltothiocyanate and the perchlorate content can be found from a calibration curve. Another aliquot is treated with an excess of nitron to precipitate both anions; the excess of nitron is then determined as nitron

2. Analysis of Nitrate-Perchlorate Mixtures

     

10.

Indirect bromometric microdetermination of nitrate and perchlorate,using nitron as reagent     

Salah Shahine  Nazira Ismael 《Mikrochimica acta》1976,66(1-2):75-79

Summary An indirect bromometric method for the determination of nitrate or perchlorate is described. A known excess of standard nitron acetate solution is added to the sample solution to precipitate the anion to be determined; the excess of reagent is then determined in the supernatant liquid by bromatometric titration. The relative standard deviation of the method is 0.7% for nitrate and 0.5% for perchlorate. Sulphate, phosphate and fluoride do not interfere and chloride does not interfere up to a concentration of 0.1 M. Bromide, iodide, chromate, nitrite and chlorate interfere but can be eliminated.

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Zusammenfassung Ein indirektes bromatometrisches Verfahren zur Bestimmung von Nitrat oder Perchlorat wurde beschrieben. Ein gemessener Überschuß einer Nitronacetatlösung bekannter Konzentration wird zur Fällung des Anions der Probe zugesetzt und im Überstand bromatometrisch zurücktitriert. Die rel. Standardabweichung beträgt 0,7% für Nitrat und 0,5% für Perchlorat. Sulfat, Phosphat und Fluorid stören nicht; Chlorid stört nicht bis zu 0,1-m Konzentration. Bromid, Jodid, Chromat, Nitrit und Chlorat stören zwar, können aber eliminiert werden.

     

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Perchlorate			Nitrate
Taken (μg)	Found (μg)	Error (%)	Taken (μg)	Found (μg)	Error (%)
400	404	+ 1.00	248	250	+0.81
400	400	0.00	496	492	?0.81
400	400	0.00	992	992	0.00
800	796	?0.50	248	248	0.00
600	602	+0.33	248	245	?1.21
800	792	?1.25	496	498	+0.40

Indirect bromometric microdetermination of nitrate and perchlorate,using nitron as reagent

Summary An indirect bromometric method for the determination of nitrate or perchlorate is described. A known excess of standard nitron acetate solution is added to the sample solution to precipitate the anion to be determined; the excess of reagent is then determined in the supernatant liquid by bromatometric titration. The relative standard deviation of the method is 0.7% for nitrate and 0.5% for perchlorate. Sulphate, phosphate and fluoride do not interfere and chloride does not interfere up to a concentration of 0.1 M. Bromide, iodide, chromate, nitrite and chlorate interfere but can be eliminated.

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Zusammenfassung Ein indirektes bromatometrisches Verfahren zur Bestimmung von Nitrat oder Perchlorat wurde beschrieben. Ein gemessener Überschuß einer Nitronacetatlösung bekannter Konzentration wird zur Fällung des Anions der Probe zugesetzt und im Überstand bromatometrisch zurücktitriert. Die rel. Standardabweichung beträgt 0,7% für Nitrat und 0,5% für Perchlorat. Sulfat, Phosphat und Fluorid stören nicht; Chlorid stört nicht bis zu 0,1-m Konzentration. Bromid, Jodid, Chromat, Nitrit und Chlorat stören zwar, können aber eliminiert werden.