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See detailObservations sous sentence Cepani n°1062
Caprasse, Olivier ULg

in Recueil des sentences arbitrales du Cepani (2005)

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See detailObservations sous sentence Cepani n°2137
Caprasse, Olivier ULg

in Recueil des sentences arbitrales du Cepani 1996-2001 (2008)

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See detailObservations spectrographiques de la comète "Ikeya-Seki" (1965f) effectuées à l'Observatoire de Haute-Provence
Dufay, Jean; Swings, Polydore ULg; Fehrenbach, Charles

in Publications de l'Observatoire de Haute-Provence (1965), 8(14), 3

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See detailObservations spectroscopiques de la comète Arend-Rolland (1956 h).
Fehrenbach, Charles; Haser, L.; Swings, Polydore ULg et al

in Annales d'astrophysique (1957), 20

Aux distances héliocentriques inférieures a 0,6 U. A., le spectre d'émission de la comète 1956h montre un doublet D anormalement intense. L'intensité du continuum est toujours élevée. On a obtenu une plus ... [more ▼]

Aux distances héliocentriques inférieures a 0,6 U. A., le spectre d'émission de la comète 1956h montre un doublet D anormalement intense. L'intensité du continuum est toujours élevée. On a obtenu une plus grande precision pour les longueurs d'onde des émissions jaunes-rouges ; celles-ci appartiennent toutes aux transitions (o, v2', o) → (o, o, o) de NH2 pour 5 ≤ v2' ≤ 10, les branches Q étant les mieux marquées. [less ▲]

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See detailObservations sur l'action détersive des solutions de savon
Spring, Walthère ULg

in Bulletin de la Société Chimique de Belgique (1910), XXIV

Spring, W. Bull. soc. belg. chim. (1910), 24, 17-54; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). cf. C. A., 3, 1,599, 1613. The theories of ... [more ▼]

Spring, W. Bull. soc. belg. chim. (1910), 24, 17-54; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). cf. C. A., 3, 1,599, 1613. The theories of soap solns. up to the present time, including one of his own previously outlined. Further work shows that Fe2O3, acts similarly to Cu in forming colloidal combinations, and in combining to produce an acid and a basic soap. Soap forms with Fe2O3 a more stable combination than Fe2O3 forms with various solids, particularly with cellulose. It is found that 3.10 mol. Fe2O3 are pptd. by 1 mol. soap when the hydrosol of FeO3H3 and soap 3 are used. Soap agglutinates the hydrosol of alumina as it does Fe. The rapidity in both cases depends upon the proportions of material mixed as well as on other factors not yet so well defined. Solns. of soap with H3SiO3, clay and cellulose behave as lampblack. The experiments show that the detergent action of soap solns. is due to the formation of a combination of adsorption with the material to be removed, the combination having lost to a great extent the adhesive power possessed by the materials before their combination. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'action détersive des solutions de savon : Deuxième communication : Les solutions de savon et les composés ferriques
Spring, Walthère ULg

in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1909), XXVIII

Spring, W. Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1910), 28, 424-43; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). see C ... [more ▼]

Spring, W. Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1910), 28, 424-43; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). see C. A., 3, 1599-1613; 4, 138. In this investigation finely divided hematite (Fe2O3) containing 4.6% H2O) was treated in a manner similar to the C described) in preceding communication. It was found that in pure H2O it remains in suspension for days, but in acid or alkaline solns. it settles in 0.5 hr. When subjected to action of electric current the tendency is to migrate toward the cathode; hence particles must be positively charged. When Fe2O2 is shaken with soap solns. of varying strength all except those with about 0.5% soap settle in 5 days or less. Those with 7-8% show a ferric color in the clear soln. The residue on evapn. of the clear 7% soln. shows 17.66% and 17.50% ash, after deducting 1.13% Fe2O3; from the same soln. not shaken with Fe2O3 18.31%. Dilute KOH solns. (less than 0.1%) do not cause settling, but as little as 0.0001% HCl does so. A soln. of soap in MeOH was shaken with Fe2O3. The residue on evapn. of the clear soln. showed 17.68% ash; from the original soln. 18.24%. This shows a decomp. of the soap into a basic and an acid portion, the latter combining with the Fe2O3. Suspension of Fe2O3 in H2O filters clear after 16 filtrations, through same paper in alc., after 4. This is due to adsorption, and not to blocking of the pores, for if H2O be poured on the paper through which alc. suspension filtered clear, it comes through more and more turbid as the alc. is washed out. If 2% soap soln. be used instead, it looks as if filter had been pierced. This indicates that Fe2O3 forms an adsorption-combination with soap more stable than with cellulose or other materials. When colloidal Fe(OH)3 solns. are shaken with soap solns. clarification is found to depend on the relative amts. of Fe(OH)3 and soap. It is most rapid when the proportion is between 2.16 and 3.47 mols. Fe2O3 to 1 of soap. By a titration method the ratio was found to be 3.10-3.25:1 when Fe(OH)3 was run into the soap; 1 when soap was run into Fe(OH)3. The ppts. in the 2 cases were almost the same in comp., and were entirely different from the Fe soap prepared by adding FeCl3 soln. to soap soln., in which the ratio is 3 mols. soap to 1 mol. Fecl3. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'action détersive des solutions de savon : Deuxième communication : Les solutions de savon et les composés ferriques
Spring, Walthère ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1909), (9-10), 949-966

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1909), 949-66; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Blood ... [more ▼]

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1909), 949-66; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Blood and colloidal hydrate of iron easily form with soap a combination of adsorption which is not sol. in H2O. This combination in presence of H2O does not have the power of adhering to glass, porcelain, cellulose, skin, etc. Hence such substances are cleaned by soap because the colloidal combination is not adsorbed by these solid substances. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'action détersive des solutions de savon : Première communication
Spring, Walthère ULg

in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1909), XXVIII

Spring, W. Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1909), 28, 120-35; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The ... [more ▼]

Spring, W. Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1909), 28, 120-35; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The action of soap is explained by the following facts: (1) Carbon hastens the decomp. of soap in water by causing the formation of an acid salt. This combination of C with the soap is not stoichiometric but a combination such as exists between colloidal substances. The combination of the C with the soap is formed because of the difference of the electrical polarity of its constituents from water. (2) C suspended in water forms a combination of absorption more or less stable with the solid substances, especially cellulose. This, the author says, is proved by the fact that a suspension of finely divided C in water will give up its C to filter paper when filtered, and if the paper is then inverted the C cannot be washed off by means of water. There exists a combination of colloidal C and paper. (3) A suspension of C in soap solution is characterized by its stability. When filtered all of the C passes through the filter paper. In his experiments the author employed a 2% soap solution and C from which all oily matter had been removed so that there was no chance for emulsions. It was found that there was an optimum % of concentration for which the C remained in suspension. In a 2% sol. the C deposited almost as rapidly as in pure water, but in solutions of less than 0.5% the deposition was slower. In a 1% sol. the C remained in suspension about 2 months. All of the soap solutions which had retained C in suspension nevertheless had a sediment. Acid and alkaline solutions of soap were tried with regard to their power of holding C in suspension. The acid solutions became clear rapidly while the alkaline held the C better than pure water does. MeOH and EtOH solutions of soap were also tried. The deposition of C from these took place more rapidly than in the case of water. Soap solutions which deposited C were examined to see whether any soap was dragged down with the C. It was found each time that the % of ash of the sol. which had been agitated with C and then filtered, was greater than the corresponding % of ash of the sol. not so treated, which was run as a comparison. The author concludes that the soap sol. was slightly decomposed by contact with the C into an acid portion which agglutinated with C and into a basic portion which remained in solution. The MeOH and EtOH sols. of soap when examined in the same manner as above showed less ash. This would mean that the solution underwent no change and that there was no agglutination with the C. This also explains why alc. solutions of soap give inferior detersive effects. The sediment of C deposited from soap solution is different in character from that deposited from pure water. It is oleaginous and viscous. A suspension of C in water was subjected to electrolysis. With a difference of potential of 8 volts cataphoresis is doubtful, but when the sol. is made slightly alkaline the C acts as if charged electropositive and is deposited around the cathode. A 0.2% soap solution when electrolyzed gave a white deposit around the anode after several hours. This, when separated from the solution and the ash determined and compared with that of the filtrate, indicates that the deposit at the anode is an acid soap while the soap left in the solution is basic. The author is carrying on experiments to show the action of silicic acid, iron oxide, Al2O3, etc., in soap solutions. Also in Arch. sci. phys. nat. g.acte.en., 27, 229. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'action détersive des solutions de savon : Première communication
Spring, Walthère ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1909), (1), 187-206

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1909), 187-206; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010 ... [more ▼]

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1909), 187-206; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Lampblack purified from fats and resins was tested for its rate of sedimentation in pure H2O, in 0.01-2% soap solns., in 0.01-2% soap solns. containing an equivalent of HCl or of KOH, and in MeOH or EtOH solns. of soap, the concentrations of soap being 1/50 and 1/60% in the MeOH and 0.02% in the EtOH. In H2O and in 2% soap soln. lampblack remained in suspension to the same extent; in 0.5% soap soln. in 6 days a small amount of lampblack remained in suspension; in I% soap soln. lampblack remained in suspension for more than 2 mos. In all cases some of the lampblack was deposited. The acid solns. in the different concentrations cleared quickly, while the alkaline solns. held the lampblack in suspension better than H2O. The alcohols acted as H2O, but to produce an effect of the same order, their mass ought to be 50-200 times as great as that of H2O. The soap soln. shaken with lampblack gave a heavier ash than the soap soln. alone. The soln. seemed to be divided into 2 parts, a more acid one which agglutinated with the lampblack and a more basic one which remained in the soln. Proof of this was found from the smaller ash remaining from the residue after treating in alc. The alc. solns. gave less of a detergent effect. The sediment of lampblack in the soap soln. differed from that in H2O by being viscous and oily while that in H2O was grainy and easily thrown into suspension in H2O. On filtration the lampblack from H2O suspensions blackened the paper completely while from soap soln. the particles not in contact with the paper were readily detached. Lampblack in pure H2O with a current of 8 volts did not conduct; in H2O rendered slightly alkaline the lampblack was deposited at the cathode; in a 2% soap soln. after some hrs. lampblack was deposited at the anode. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'action détersive des solutions de savon : Quatrième et dernière communication : Les solutions de savon et l'acide silicique, l'argile et la cellulose
Spring, Walthère ULg

in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1910), XXIX

Spring, W. Luttich. Rec. trav. chim. (1910), 29(1), 8; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). see also C. A., 4, 138, 969. Study of the ... [more ▼]

Spring, W. Luttich. Rec. trav. chim. (1910), 29(1), 8; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). see also C. A., 4, 138, 969. Study of the action of hydrated iron oxide, 7Fe2O3.3H2O on soap soln. of varying conc. led to the conclusions that the optimum suspension conc. of the soap soln. is 0.5%, that the soap splits into a basic and acid part, the basic combining with the Fe2O3 and the acid part remaining in soln., and that a soap soln. will remove Fe2O3 from its adsorption compds. with cellulose. Substituting an Fe hydrosol for the Fe2O3 it was found that pptn. occurred between limiting ratios of the soap to hydrosol, i. e., between 1 of soap to 2.16 of Fe2O3 and 1 of soap to 3.47 Fe2O3. The pptn. of Al2O3, with soap soln. shows a periodicity, the ratios of soap to Al2O3 in those solns. which become clear being approx. 8.33, 4.16, 2.06. If the wt. of Al2O3. exceeds that of the soap no pptn. occurs. A large excess of soap, 20 times the wt. of Al2O3, gives a suspension optimum, whereas 80 times the wt. of Al2O3 gives pptn. The speed of the reaction depends primarily on the ratio of the reacting substances. 7SiO2.3H2O combines with a basic constituent of soap, leaving an acid constituent of low ash in soln. The % of ash in the soap in soln. increases when more dil. soap solns. are used, due to soln. of SiO2. The adsorption compd. of basic soap with SiO2 dissociates on shaking with H2O. A pptn. optimum occurs at 1/8% soap soln., and a suspension optimum at 1/16 and 1/2%. A hydrated clay gave approx. the same results, pptg. about 60% of the soap from a 1/2% soln. The soap has a solvent action on the clay, a 1/8% soap soln. giving the highest ratio of suspended clay to soap. A suspension optimum for the settling of clay in soap soln. is found at 1/32% soap soln. Cellulose forms an adsorption compd. with the basic constituents of soap, the cleavage of the soap being noticeable only in concs. above 1%. The cleansing action of soap is due to the formation of an adsorption compd. with the material to be removed, which thus loses its adhesive properties. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'action détersive des solutions de savon : Quatrième et dernière communication : Les solutions de savon et l'acide silicique, l'argile et la cellulose
Spring, Walthère ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1909), (12), 1128-1139

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See detailObservations sur l'action détersive des solutions de savon : Troisième communication : Les solutions de savon et l'hydrosol aluminique
Spring, Walthère ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1909), (11), 1059-1065

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See detailObservations sur l'action détersive des solutions de savon : Troisième communication : Les solutions de savon et l'hydrosol aluminique
Spring, Walthère ULg

in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1910), XXIX

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See detailObservations sur l'adage: Periculum est emptoris
Gerkens, Jean-François ULg

in Cahiers du Centre de Recherches en Histoire du Droit et des Institutions (2002), (17), 117-133

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See detailObservations sur l'efficacité de la nouvelle passe à poissons sur l'Aisne à Bomal
Philippart, Jean-Claude ULg; Birtles, Cymon; Giroux, Florian et al

Article for general public (1996)

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See detailObservations sur l'enseignement supérieur
De Cuyper, Charles ULg

Speech (1870)

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See detailObservations sur l'hydrolyse du chlorure ferrique
Spring, Walthère ULg

in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique. 2eme serie (1897), XVI

Spring, W. Rec. trav. chim. Pays-Bas (1897), 16(2), 237-49; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The decomposition of the ferric ... [more ▼]

Spring, W. Rec. trav. chim. Pays-Bas (1897), 16(2), 237-49; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The decomposition of the ferric chloride by water already shown of H. Debray (Bulletin of the Chemical Society, Paris 12. 346), after which researcher a very much diluted neutral, nearly colorless iron perchloride solution dissociates with heating up under strong coloring into hydrochloric acid and colloidal ferric oxide. Beside the latter F. W. Krecke (Journal pr. Chemistry 3. 286) found an iron oxychloride compound. After F. Wiedemann (Journal pr. Chemistry, 9. 145) the magnetism of the ferric chloride solutions consists of the sum of the magnetism of the iron in the colloidal oxide and the magnetism of the iron is not changed chloride and therefore no basic salts will give, in which the iron possesses its own atomic magnetism. The studied solutions were middle concentration (30% to 0.06%), however not border lines. Antony and Giglio (Chem.-Newspaper 1895. 325; C. 95. II. 858) the decomposition of the ferric chloride found completed in hydrogen chloride and colloidal hydrate after 24 hours according to colorimetric method with dilutions up to 0.00083%. The latter happens under temporary formation of chlorohydrates, [FeCl2.OH and FeCl(OH)2], which depending upon applied water conditions with hydrogen chloride equilibrium systems form and also cause during the dilution of the irregularities arising in the color of the solution. These changes in the color the line conduction of the iron perchloride solutions follows after Goodwin (Journal of Physik. Chemistry, 21. 1; C. 96. II. 998) a sufficient dilution of the first ionization of the ferric chloride causes, on which the ions (Fe) unite with the ions (OH) first to the colorless, bivalent ions Fe(OH), which gives the colloidal brown ferric hydroxide then with further ions of OH. xFe(OH)... + 2x(OH) = xFe(OH)3. The decomposition of the ferric chloride will exist therefore not in a simple hydrolysis in hydrate and hydrogen chloride, but will be accompanied by ionization features. Solutions concentrated by the author implemented experiments with ferric chloride resulted in the following. Sublimated ferric chloride Fe2Cl6 separates in water without decomposition then only if the relationship of the solvent is extraordinarily small. With the increase of the latter place shift takes place in the ferric chloride, whereby the delivery is prepared of two of the six chlorine atoms. The salt regards now as a composition of Ferrochloride and chlorine Fe2Cl4.Cl2, which dissociates with increase of water completely into the groups of the Fe2Cl4 and Cl2, if these groups can accept the neutral electrical condition. Chlorine in the status nascent reacts then with the water under formation of hydrogen chloride and oxygen, which transfer the group of Fe2Cl4 immediately into the Oxychloride Fe2Cl4O, which accepts the certain following structure: 3Fe2Cl4O = Fe2O3.2Fe2Cl6 and forms with hydrochloric acid and the water an equilibrium system modifying with the temperature. With still further dilution of the solution arrives by the designated phases at the complete decay. In van't Hoff's opinion about the nature of the solutions proven that the expansion of a salt draws the same consequences by its solvent, like those by increase of the temperature. Reaction of the potassium ferricyanide. Potassium ferricyanide does not give a low-brown color with ferric salt solutions of middle concentration, a clear reaction with a very much concentrated solution of ferric chloride (230%), with a 126% solution against it immediately a precipitation of citizen of Berlin blue and development of chlorine, from which it must be closed that the ferric chloride splits in the solution into Ferrochloride and chlorine: Fe2Cl6 = Fe2Cl4 + Cl2. Similarly behave after author ferric bromide, ferric iodide and ferric nitrate, only takes place slower at the latter the formation precipitation of citizen of Berlin-blue, therefore the dissociation: Fe2(NO3)4 + N2O5 + O seems to take place with difficulty; more rapidly the latter is caused with addition by some barium carbonate. Despite this behavior one may not really regard a solution of ferric chloride consisting of Fe2Cl4 and Cl2, as soon as chlorine leaves the compound, with the Fe2Cl4 and Cl2 an electrical charge is caused, whereby the Ferrochloride as cation and chlorine function as anion. Between these ions results an electrostatic attraction, which opposes its complete separation. Chlorine reacted with the water under formation from HCl, what latter by an air flow can be removed, while the oxygen remains connected with the group of Fe2Cl4 : Fe2Cl6 + H2O = Fe2Cl4O + 2HCl. About the reaction of the iron with ferric chloride. A metal plate from iron does not react nearly with a saturated ferric chloride solution. The iron separates into less concentrated solutions, all faster, the more easily these solutions with potassium ferricyanide give citizen of Berlin-blue. It is not the formation of the Ferrochloride, a consequence of the dissolution of the iron, but is from the latter cause, as due to the dissociation (see above) formed hydrochloric acid dissolves the iron under development of hydrogen. If with these location of the ferric chloride, the FeCl2 cation and Cl2 anion and between these ions make an electrostatic attraction valid (see above), then must have a difference of potential be stated and an electric current to be able to collected, whose intensity will depend on the dissociation of the ferric chloride. On the other hand, one will cause the delivery of the ions with the current conclusion, brings and/or the dispersion of FeCl2 and Cl2 without difficulty to conditions - an opinion, which was confirmed by the experiment. A small platinum cap flat at the reason is fastened on by means of metal catch of the ends of a galvanometer, given into the same a confirmed FeCl3-solution (laminate 5-6 mm) and brought a small iron disk (2 cm diameters)on the surface of the liquid which is connected with the other end of the galvanometer. In instants of the contact, the needle turn out into violent oscillations and places with the division 54°. After 4 hours, 4 cg had more separated iron than in a simultaneous experiment which the flow was not closed. The latter went from the iron to platinum, so that this cathode and the iron were anode. With the use of more diluted solutions of FeCl3 increases the intensity of the flow up to a solution of 40%, on which it decreases with the further dilution regularly, thus it goes through a maximum. Also the ease give with solutions of ferric chloride citizen of Berlin-blue under delivery of chlorine, walks by a maximum. In the end it is noticed that the investigations of the author, also contribute to the answer of the question of the molecular formula of the ferric chloride, which after the density of the formula Fe2Cl6, according to the b.p.-method in alcohol or ether solution however comes the formula FeCl3. It is still determined whether the place mixture of chlorine in the ferric chloride has solution not also in alcoholic or ethers. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'hydrolyse du chlorure ferrique
Spring, Walthère ULg

in Bulletin de l'Académie Royale des Sciences, des Lettres et des Beaux-Arts de Belgique. Sciences. 3e série (1897), XXXIV(8), 255-268

Spring, W. Bull. Acad. roy. Belgique (1897), 34(3), 255-68; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The decomposition of the ferric ... [more ▼]

Spring, W. Bull. Acad. roy. Belgique (1897), 34(3), 255-68; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The decomposition of the ferric chloride by water already shown of H. Debray (Bulletin of the Chemical Society, Paris 12. 346), after which researcher a very much diluted neutral, nearly colorless iron perchloride solution dissociates with heating up under strong coloring into hydrochloric acid and colloidal ferric oxide. Beside the latter F. W. Krecke (Journal pr. Chemistry 3. 286) found an iron oxychloride compound. After F. Wiedemann (Journal pr. Chemistry, 9. 145) the magnetism of the ferric chloride solutions consists of the sum of the magnetism of the iron in the colloidal oxide and the magnetism of the iron is not changed chloride and therefore no basic salts will give, in which the iron possesses its own atomic magnetism. The studied solutions were middle concentration (30% to 0.06%), however not border lines. Antony and Giglio (Chem.-Newspaper 1895. 325; C. 95. II. 858) the decomposition of the ferric chloride found completed in hydrogen chloride and colloidal hydrate after 24 hours according to colorimetric method with dilutions up to 0.00083%. The latter happens under temporary formation of chlorohydrates, [FeCl2.OH and FeCl(OH)2], which depending upon applied water conditions with hydrogen chloride equilibrium systems form and also cause during the dilution of the irregularities arising in the color of the solution. These changes in the color the line conduction of the iron perchloride solutions follows after Goodwin (Journal of Physik. Chemistry, 21. 1; C. 96. II. 998) a sufficient dilution of the first ionization of the ferric chloride causes, on which the ions (Fe) unite with the ions (OH) first to the colorless, bivalent ions Fe(OH), which gives the colloidal brown ferric hydroxide then with further ions of OH. xFe(OH)... + 2x(OH) = xFe(OH)3. The decomposition of the ferric chloride will exist therefore not in a simple hydrolysis in hydrate and hydrogen chloride, but will be accompanied by ionization features. Solutions concentrated by the author implemented experiments with ferric chloride resulted in the following. Sublimated ferric chloride Fe2Cl6 separates in water without decomposition then only if the relationship of the solvent is extraordinarily small. With the increase of the latter place shift takes place in the ferric chloride, whereby the delivery is prepared of two of the six chlorine atoms. The salt regards now as a composition of Ferrochloride and chlorine Fe2Cl4.Cl2, which dissociates with increase of water completely into the groups of the Fe2Cl4 and Cl2, if these groups can accept the neutral electrical condition. Chlorine in the status nascent reacts then with the water under formation of hydrogen chloride and oxygen, which transfer the group of Fe2Cl4 immediately into the Oxychloride Fe2Cl4O, which accepts the certain following structure: 3Fe2Cl4O = Fe2O3.2Fe2Cl6 and forms with hydrochloric acid and the water an equilibrium system modifying with the temperature. With still further dilution of the solution arrives by the designated phases at the complete decay. In van't Hoff's opinion about the nature of the solutions proven that the expansion of a salt draws the same consequences by its solvent, like those by increase of the temperature. Reaction of the potassium ferricyanide. Potassium ferricyanide does not give a low-brown color with ferric salt solutions of middle concentration, a clear reaction with a very much concentrated solution of ferric chloride (230%), with a 126% solution against it immediately a precipitation of citizen of Berlin blue and development of chlorine, from which it must be closed that the ferric chloride splits in the solution into Ferrochloride and chlorine: Fe2Cl6 = Fe2Cl4 + Cl2. Similarly behave after author ferric bromide, ferric iodide and ferric nitrate, only takes place slower at the latter the formation precipitation of citizen of Berlin-blue, therefore the dissociation: Fe2(NO3)4 + N2O5 + O seems to take place with difficulty; more rapidly the latter is caused with addition by some barium carbonate. Despite this behavior one may not really regard a solution of ferric chloride consisting of Fe2Cl4 and Cl2, as soon as chlorine leaves the compound, with the Fe2Cl4 and Cl2 an electrical charge is caused, whereby the Ferrochloride as cation and chlorine function as anion. Between these ions results an electrostatic attraction, which opposes its complete separation. Chlorine reacted with the water under formation from HCl, what latter by an air flow can be removed, while the oxygen remains connected with the group of Fe2Cl4 : Fe2Cl6 + H2O = Fe2Cl4O + 2HCl. About the reaction of the iron with ferric chloride. A metal plate from iron does not react nearly with a saturated ferric chloride solution. The iron separates into less concentrated solutions, all faster, the more easily these solutions with potassium ferricyanide give citizen of Berlin-blue. It is not the formation of the Ferrochloride, a consequence of the dissolution of the iron, but is from the latter cause, as due to the dissociation (see above) formed hydrochloric acid dissolves the iron under development of hydrogen. If with these location of the ferric chloride, the FeCl2 cation and Cl2 anion and between these ions make an electrostatic attraction valid (see above), then must have a difference of potential be stated and an electric current to be able to collected, whose intensity will depend on the dissociation of the ferric chloride. On the other hand, one will cause the delivery of the ions with the current conclusion, brings and/or the dispersion of FeCl2 and Cl2 without difficulty to conditions - an opinion, which was confirmed by the experiment. A small platinum cap flat at the reason is fastened on by means of metal catch of the ends of a galvanometer, given into the same a confirmed FeCl3-solution (laminate 5-6 mm) and brought a small iron disk (2 cm diameters)on the surface of the liquid which is connected with the other end of the galvanometer. In instants of the contact, the needle turn out into violent oscillations and places with the division 54°. After 4 hours, 4 cg had more separated iron than in a simultaneous experiment which the flow was not closed. The latter went from the iron to platinum, so that this cathode and the iron were anode. With the use of more diluted solutions of FeCl3 increases the intensity of the flow up to a solution of 40%, on which it decreases with the further dilution regularly, thus it goes through a maximum. Also the ease give with solutions of ferric chloride citizen of Berlin-blue under delivery of chlorine, walks by a maximum. In the end it is noticed that the investigations of the author, also contribute to the answer of the question of the molecular formula of the ferric chloride, which after the density of the formula Fe2Cl6, according to the b.p.-method in alcohol or ether solution however comes the formula FeCl3. It is still determined whether the place mixture of chlorine in the ferric chloride has solution not also in alcoholic or ethers. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailObservations sur l'utilisation de traitements gonadotropes répétés chez la chèvre laitière
Baril, Gérard; Remy, Benoît ULg; Vallet, J. C. et al

in Annales de Zootechnie (1992), 41(3-4), 291-296

Observations on the repeated use of gonadotropin treatments in the dairy goat. Our studies have attempted to determine if the absence of oestrus observed in some goats after fluorogestone acetate-pregnant ... [more ▼]

Observations on the repeated use of gonadotropin treatments in the dairy goat. Our studies have attempted to determine if the absence of oestrus observed in some goats after fluorogestone acetate-pregnant mare serum gonadotropin (FGA-PMSG) treatments could be due to its repeated use. An experiment was carried out in a Saanen flock, in which she-goats were submitted to FGA-PMSG treatment each year. The first treatment of the year was performed on 169 shegoats between March and August 1989. Of the females diagnosed as non-pregnant following the first treatment, 38 were treated a second time during the same period. The proportion of females which went into oestrus after the first treatment was lower in 59 multiparous goats than in 64 nulliparous and in 46 primiparous goats (64.4 vs 100 and 97.8%; P < O.Oi). For the she-goats treated twice, the percentage of females which went into oestrus after the second treatment was lower than that observed after the first treatment (44.7 vs 71.0%; P < 0.05). The presence of anti-PMSG antibodies in plasma was investigated in blood samples taken before and after each treatment. Results are expressed as % of radioactive PMSG bound by 10 pl of blood plasma. Before the first treatment, the percentage of bound PMSG was higher in multiparous than in nulliparous and primiparous goats (17.5 t 23.1 vs -0.06 t 0.7 ; 1.2 ± 1.9 ; P < 0.01), and increased after treatment for all parities. In goats treated twice, the percentage of bound PMSG before the second treatment was higher than that observed before first treatment (22.8 t 23. vs 11.2 f 19.7; P < 0.05). For both treatments, females which did not come into oestrus showed a percentage of bound PMSG which was significantly higher than that of goats in which oestrus was observed (multiparous first treatment: 30.5 f 23.6 vs 1I 2. 9 20. 1 %; she-goats in second treatment: 33.9 ± 23.1 vs 9.2 ± 14.5T.). When the percentage of bound PMSG before treatment was low (< 5°l) in multiparous goats, the oestrus and kidding rates after the first treatment did not differ from those observed in nulliparous and primiparous goats. The decrease in the efficiency of the treatments was therefore not due to the age of animals. The repeated use of FGA-PMSG during the lifetime of goats or within the same year is followed by an increase in the levels of antibodies against PMSG. The presence of those antibodies may explain the decrease in the efficiency of these treatments in inducing and synchronizing oestrus. [less ▲]

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See detailObservations sur la cimentation des biohermes "de marbre rouge" du Frasnien de la Belgique
Boulvain, Frédéric ULg

in Annales de la Société Géologique de Belgique (1989), 112

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