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See detailSur la couleur du glycol éthylénique et de la glycérine
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in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1908), XXVII

Spring, W. Liege. Rec. trav. chim. (1908), 27, 110-6; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). From the study of the color of long columns ... [more ▼]

Spring, W. Liege. Rec. trav. chim. (1908), 27, 110-6; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). From the study of the color of long columns of water, ethyl alcohol, glycol, and glycerol, the author concludes that organic liquids containing OH groups have a blue color, the intensity of the color bearing some relation, if it is not directly proportional, to the number of these groups. Incidentally, he finds that the addition of water is necessary to remove by means of animal charcoal all dark colored impurities from the liquids with which he worked. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailNote complémentaire sur l'origine des nuances vertes des eaux de la nature
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in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1908), (3), 262-272

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1908), (No. 3), 262-72; 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 (1908), (No. 3), 262-72; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author proved by observing long tubes of dilute suspensions of silica and mastic in water that brown tints may thus easily arise, but he obtained green tints only from colloidal suspensions of alumina and silica. The diffraction of light in such suspensions and not the nature of the suspended particles is therefore the cause, under certain circumstances at any rate, of the green tint of natural waters. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la couleur du glycol éthylénique et de la glycérine
Spring, Walthère ULg

in Archives des Sciences Physiques et Naturelles (1908), 25

Spring, W. Archives des Sciences Physiques et Naturelles (1908), 25, 5-14; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Glycol and Glycerol, if ... [more ▼]

Spring, W. Archives des Sciences Physiques et Naturelles (1908), 25, 5-14; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Glycol and Glycerol, if diluted slightly with water, lost their brown tint on filtration through animal charcoal and showed a blue color when observed through a long tube. The color was deeper than that of water or ethyl alcohol, indicating that the depth of color bears a relation to the number of hydroxyl groups present. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la couleur du glycol éthylénique et de la glycérine
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in Bulletin de la Société Chimique de Belgique (1908), XXII(1), 10-17

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See detailSur les modifications subies par quelques phosphates acides à la suite d'une compression ou d'une déformation mécanique
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in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1907), XXVI

Spring, W. Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1907), 26, 188-202; 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 (1907), 26, 188-202; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author subjected several acid phosphates to high pressures in a specially constructed cylinder with the following results: Ca(H2PO4)2H2O loses first its water of crystallization and finally a portion of the phosphoric acid, these two constituents being forced out of the compression cylinder. In general those constituents which were capable of liquefying under the pressure were found to be eliminated most readily. The acid phosphates of calcium, sodium and probably lithium form molecular compounds with their respective sulphates, that of calcium being insoluble in water and probably constituting one of the causes of reversion. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la densité et l'état allotropique de certaines variétés de soufre : Remarque sur la détermination de la densité des corps en poudre fine
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in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique. 2e série (1907), XXVI

Spring, W. Recueil des Travaux chimiques des Pays-Bas et de la Belgique (1908), 26, 357-72;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 (1908), 26, 357-72;SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author prepared "milk of sulphur" by treating KnS with dil. HCl, and also by passing H2S into FeCl3 solution. The S from the K2Sn was completely sol. in CS2 and had a density of 2.0555, which is approximately the same as that of rhombic S. That from H2S was soluble CS2 to the extent of 96.8% only, and the density of the soluble portion was 2.0658, while that of the insoluble was 1.8686. The greater part of the sulphur from the K2Sn was therefore identical with that from H2S. This conclusion was confirmed by measuring their specific heats Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la couleur du glycol éthylénique et de la glycérine
Spring, Walthère ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1907), (12), 1031-1040

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See detailSur les modifications subies par quelques phosphates acides à la suite d'une compression ou d'une déformation mécanique
Spring, Walthère ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1907), (3), 193-211

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1907), 193-211; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The ... [more ▼]

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1907), 193-211; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author shows by expts. that: (1) Mech. deformation of primary phosphates involves their partial decompn. This commences with elimination of water of hydration and terminates with liberation of a certain amt. of phosphoric acid. The reversion of certain phosphates is facilitated by deformation. The decompn. appears to be more profound when the compds. resulting from it are liqs., i.e., in a form susceptible of elimination under pressure. The success or failure of the reaction is, then, directly connected with the mech. rather than the chem. conditions affecting the matter. (2) The primary phosphates of Ca and Na, probably also that of Li, form mol. combinations with the resp. sulfates. With calcium compds. this combination appears insol. in water and its formation can contribute to the reversion of the acid phosphates. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur les modifications subies par quelques phosphates acides à la suite d'une compression ou d'une déformation mécanique
Spring, Walthère ULg

in Archives des Sciences Physiques et Naturelles (1907), 23

Spring, W. Archives des Sciences Physiques et Naturelles (1907), 23, 229-45; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author subjected ... [more ▼]

Spring, W. Archives des Sciences Physiques et Naturelles (1907), 23, 229-45; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author subjected several acid phosphates to high pressures in a specially constructed cylinder with the following results: Ca(H2PO4)2H2O loses first its water of crystallization and finally a portion of the phosphoric acid, these two constituents being forced out of the compression cylinder. In general those constituents which were capable of liquefying under the pressure were found to be eliminated most readily. The acid phosphates of calcium, sodium and probably lithium form molecular compounds with their respective sulphates, that of calcium being insoluble in water and probably constituting one of the causes of reversion. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la densité et l'état allotropique de certaines variétés de soufre : Remarque sur la détermination de la densité des corps en poudre fine
Spring, Walthère ULg

in Bulletin de la société chimique de Belgique (1907), XXI(7), 243-257

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See detailSur la densité et l'état allotropique de certaines variétés de soufre : Remarque sur la détermination de la densité des corps en poudre fine
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in Journal de Chimie Physique (1907), V

Spring, W. Journal de Chimie Physique et de Physico-Chimie Biologique (1907), 5, 410-26 ; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The ... [more ▼]

Spring, W. Journal de Chimie Physique et de Physico-Chimie Biologique (1907), 5, 410-26 ; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The author prepared "milk of sulphur" by treating KnS with dil. HCl, and also by passing H2S into FeCl3 solution. The S from the K2Sn was completely sol. in CS2 and had a density of 2.0555, which is approximately the same as that of rhombic S. That from H2S was soluble CS2 to the extent of 96.8% only, and the density of the soluble portion was 2.0658, while that of the insoluble was 1.8686. The greater part of the sulphur from the K2Sn was therefore identical with that from H2S. This conclusion was confirmed by measuring their specific heats Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur les modifications subies par quelques phosphates acides à la suite d'une compression ou d'une déformation mécanique
Spring, Walthère ULg

in Bulletin de la Société Chimique de Belgique (1907), XXI(3), 91-103

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See detailSur la densité et l'état allotropique de certaines variétés de soufre : Remarque sur la détermination de la densité des corps en poudre fine
Spring, Walthère ULg

in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1907), (6), 684-708

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See detailSur l'origine des nuances vertes des eaux de la nature et sur l'incompatibilité des composés calciques, ferriques et humiques en leur milieu
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in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1906), XXV

Spring, W. Recueil des Travaux Chimiques des Pays-Bas (1906), 25, 32-39; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). After Baron V. AUFSESS ... [more ▼]

Spring, W. Recueil des Travaux Chimiques des Pays-Bas (1906), 25, 32-39; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). After Baron V. AUFSESS (Die Farbe der Seen. Inaug.-Diss. Muenchen 1903) the refraction of the light does not have influence on the change of the blue color water, mainly also because one can obtain green water by dissolving lime compounds/connections, yellow or brown water by solve ones of humus substances in pure water. The going by experiments of the authors, which are down partly in detail described, led however to the subsequent results: the lime compounds/connections natural water do not have inherent color and are not a cause of the much-observed green coloring in with examination appearing even clear lime water; the green, after elimination of the dyes residual coloring contained in the water is the result of the refraction of the light through invisible portion cups, which the water still includes, and whose presence can be done by an intensive light beam. The lime compounds/connections affect strongly fell in the water contained the ferric compounds/connections and with these on the humus substances, which the latter natural color water strongly change. Lime salts protect therefore the blue color water. In case of the not-blue, lime-containing, natural water an equilibrium between the cleaning effect of their lime compounds/connections results and steady influxes of the humus and ferric compounds/connections, which let disappear its brown coloring lower for itself the blue color water. The blue, more or less greenish color of the purest water give information over the point, where the equilibrium between the antagonists is fixed. Purely blue water (6 m coating thickness) becomes green by dissolving lime from Icelandic double spar; when introducing CO2 a clear, somewhat less green solution of acid calcium carbonate forms; also gypsum colors such water green. During the passage of radiation of electrical light these solutions appear, particularly the CaH2(CO3)2-containing, optically clouds, it carefully to dry was evaporated, the residue contained partially organic substance, partially SiO2 or silicates (from the glass of the container), which were contained in the solution therefore in the colloidal condition. After filtering the other Ca-containing solutions by animal charcoal these showed the same blue color as pure water. When regarding by a pipe of 6 m length appears pure water with 1/1 000 000 part ferric hydroxide brown, with 1/2 000 000 green, with 1/5 000 000 unmodified blue. With humus substances the blue color is already changed by more than 1/40 000 000 part. Ferric salts color brownish; they are particularly reduced by humus substances, in the light, sometimes partially to ferrous compounds/connections, whose color is not possible, and which with the humus substances insoluble, failing compounds to be received. To a liter of clear solution with 1/3 000 000 if part colloidal Fe(OH) 3 (to dissolve of FeCl3 in H2O) is added a same volume acid calcium carbonate or CaSO4-Solution, then a flocculation, tags begins is because of the container soil a brown, ocher-colored dirt, the water is perfectly clear, appears green and leaves a residue of CaCO3 or CaSO4 without trace iron after few instants; the sediment contains 85-90% Fe(OH)3, CaCO3 or CaSO4. Also with insoluble CaCO3 begins the flocculation of the ferric compounds/connections immediately; similarly soluble salts work; with sodium chloride (sea water) a trace remains iron in solution. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur un hydrate de soufre
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in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1906), XXV

Spring, W. Recueil des Travaux Chimiques des Pays-Bas (1906), 25, 253-9 ; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The sulphur which is ... [more ▼]

Spring, W. Recueil des Travaux Chimiques des Pays-Bas (1906), 25, 253-9 ; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). The sulphur which is formed together with polythionic acids when hydrogen sulphide and sulphur dioxide react in aqueous solution is a mixture of soluble sulphur and a definite hydrate, S8,H2O, and not a new allotropic form of sulphur, "sulphur δ", as described by Debus (Chem. News, 1888, 57, 87). In order to separate the hydrate from the soluble sulphur, the mixed precipitate in washed by dialysis until it is neutral to litmus, and dried in a vacuum at the ordinary temperature until the weight is constant; the yellow mass thus obtained is powdered, sifted through silk, again dried in a vacuum, and finally extracted with carbon disulphide, which dissolves 51.6 per cent. of the total mass. The residual sulphur hydrate, S8,H2O, when compressed into cylinders, has a sp. gr. 1.9385 at 19°/4°, loses its water at 80°, and has a slight vapour pressure at the ordinary temperature, the powdered substance losing 2.41 per cent. and the compressed substance 1.33 per cent. when kept over sulphuric acid for 205 days. The partially dried powder contains 3.1 per cent. and the compressed substance 5.8 per cent. of sulphur soluble in carbon disulphide. If, however, the hydrate consisted of octahedral sulphur combined with water, the amount of soluble sulphur in the partially dried powder would be 35.186 per cent.; it is probable, therefore, that the hydrate is derived from an amorphous unstable variety of sulphur which is transformed slowly under ordinary conditions, and more rapidly under pressure, into soluble sulphur. Reprinted with the permission of the American Chemical Society. Copyright © 2010 American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur un hydrate de soufre
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in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1906), (7), 452-459

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1906), 1906, 452-59; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). If ... [more ▼]

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1906), 1906, 452-59; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). If one lets sulfurous acid in water and hydrogen sulfide work on the other, then Polythionic acid form and sulfur, what latter after DEBUS (Chem. News 57. 87) a new allotropic modification with the ability to form with water a colloidal solution is to be (sulfur δ). The alleged Pentathionic acid shows up with intensive illumination not as an homogeneous body, but as a colloidal solution, and the sulfur δ of DEBUS not a allotropic modification, but a hydrate is S8•H2O. One receives it, if one removes and up to the constant weight in the vacuum dries the acid from with above reaction the formed S by months-long dialyze with daily fresh water, as a yellowish, partially translucent mass from conchoidal break; there is 51.6% sulfur when washing with CS2. The part unsolvable in CS2 dismisses from about 80° at water, with the melting point of the S the formula S8•H2O appropriate quantity (S8 = molecular size of the firm S!). The density of hydrate pressed in cylinder form amounts to with 19°, related to water of 4°, 1.9385; meadow after 93.6/2.07 6.4/1 = 51.6; = 100/51.6 = 1.9380 on octahedral S, if were residual insoluble S not after removal water in CS2. Powdered hydrate loses 2.41% H2O, the pressed 1.33% with 7-monthly standing over H2SO4; it thus has a vapor pressure. A part of hydrate is destroyed; simultaneous increased its density. If the drained body with water remains in contact, then the density decreases again; it exists thus a condition of the S, which connects itself directly with water, and which delivers the water in the dry medium again. In the desiccator partially S give in powder form 3.1%, in the pressed condition 5.8% at CS2 in solution dehydrated. Pressure favors thus the transition of the matter to a condition of larger density. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur l'origine des nuances vertes des eaux de la nature et sur l'incompatibilité des composés calciques, ferriques et humiques en leur milieu
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in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1905), (7), 300-309

Spring, W. Bull. de l'Acad. royale de Belg. (1905), 1905, 300 to 310; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). After Baron V. AUFSESS (Die ... [more ▼]

Spring, W. Bull. de l'Acad. royale de Belg. (1905), 1905, 300 to 310; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). After Baron V. AUFSESS (Die Farbe der Seen. Inaug.-Diss. Muenchen 1903) the refraction of the light does not have influence on the change of the blue color water, mainly also because one can obtain green water by dissolving lime compounds/connections, yellow or brown water by solve ones of humus substances in pure water. The going by experiments of the authors, which are down partly in detail described, led however to the subsequent results: the lime compounds/connections natural water do not have inherent color and are not a cause of the much-observed green coloring in with examination appearing even clear lime water; the green, after elimination of the dyes residual coloring contained in the water is the result of the refraction of the light through invisible portion cups, which the water still includes, and whose presence can be done by an intensive light beam. The lime compounds/connections affect strongly fell in the water contained the ferric compounds/connections and with these on the humus substances, which the latter natural color water strongly change. Lime salts protect therefore the blue color water. In case of the not-blue, lime-containing, natural water an equilibrium between the cleaning effect of their lime compounds/connections results and steady influxes of the humus and ferric compounds/connections, which let disappear its brown coloring lower for itself the blue color water. The blue, more or less greenish color of the purest water give information over the point, where the equilibrium between the antagonists is fixed. Purely blue water (6 m coating thickness) becomes green by dissolving lime from Icelandic double spar; when introducing CO2 a clear, somewhat less green solution of acid calcium carbonate forms; also gypsum colors such water green. During the passage of radiation of electrical light these solutions appear, particularly the CaH2(CO3)2-containing, optically clouds, it carefully to dry was evaporated, the residue contained partially organic substance, partially SiO2 or silicates (from the glass of the container), which were contained in the solution therefore in the colloidal condition. After filtering the other Ca-containing solutions by animal charcoal these showed the same blue color as pure water. When regarding by a pipe of 6 m length appears pure water with 1/1 000 000 part ferric hydroxide brown, with 1/2 000 000 green, with 1/5 000 000 unmodified blue. With humus substances the blue color is already changed by more than 1/40 000 000 part. Ferric salts color brownish; they are particularly reduced by humus substances, in the light, sometimes partially to ferrous compounds/connections, whose color is not possible, and which with the humus substances insoluble, failing compounds to be received. To a liter of clear solution with 1/3 000 000 if part colloidal Fe(OH) 3 (to dissolve of FeCl3 in H2O) is added a same volume acid calcium carbonate or CaSO4-Solution, then a flocculation, tags begins is because of the container soil a brown, ocher-colored dirt, the water is perfectly clear, appears green and leaves a residue of CaCO3 or CaSO4 without trace iron after few instants; the sediment contains 85-90% Fe(OH)3, CaCO3 or CaSO4. Also with insoluble CaCO3 begins the flocculation of the ferric compounds/connections immediately; similarly soluble salts work; with sodium chloride (sea water) a trace remains iron in solution. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la limite de visibilité de la fluorescence et sur la limite supérieure du poids absolu des atomes
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in Recueil des Travaux Chimiques des Pays-Bas et de la Belgique (1905), XXIV

Spring, W. Recueil des Travaux Chimiques des Pays-Bas (1905), 24, 297-304; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Compare de Bruyn and ... [more ▼]

Spring, W. Recueil des Travaux Chimiques des Pays-Bas (1905), 24, 297-304; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). Compare de Bruyn and Wolff, Abstr., 1904, ii, 470. The fluorescence of a solution of fluorescein or of eosin in optically transparent water (Abstr., 1899, ii, 537) becomes invisible in daylight when the amount of the fluorescent substance present falls to 0.000,000,01 gram per c.c., and is just visible at the apex of a powerful beam of electric light when the concentration is 0.000,000,000,000,001 gram per c.c. It is found that the area of liquid illuminated by the apex of the cone of light must be at least 1 sq. mm. in order to render the fluorescence visible, and consequently, assuming that 1 cubic millimetre of the liquid contains at least one molecule of fluorescein (mol. wt. 408) for example, then the weight of an atom of hydrogen would be 2.5 × 10-21 grams. This value, which represents only the higher limit among possible values, is much smaller than those arrived at from other considerations by Clerk Maxwell, Kelvin, de Heen, Annaheim, and others. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved. [less ▲]

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See detailSur la limite de visibilité de la fluorescence et sur la limite supérieure du poids absolu des atomes d'hydrogène
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in Bulletin de la Classe des Sciences. Académie Royale de Belgique (1905), (5), 201-211

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1905), 201-11; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). A ... [more ▼]

Spring, W. Bulletin de la Classe des Sciences, Academie Royale de Belgique (1905), 201-11; SciFinder (Chemical Abstracts Service: Columbus, OH); https://scifinder.cas.org (accessed July 8, 2010). A solution of fluorescein in optically pure water was subjected to the action of a powerful beam of electric light, and the limit of dilution was observed at which a visible green fluorescence was produced. Assuming under these conditions that one cubic millimetre of the solution contained one molecule of fluorescein (C20H10O5K2 = 408), the value 2.5 × 10-21 grams is obtained for the superior limit of the weight of the atom of hydrogen, which is one-twenty-thousand-millionth part of the value 5 × 10-11 calculated by Annaheim (this Journal, 1877, i, 31), but is about seven thousand times as great as the value 3.45 × 10-25 calculated from the kinetic theory of gases. Reprinted with the permission of the American Chemical Society. Copyright © 2010. American Chemical Society (ACS). All Rights Reserved [less ▲]

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See detailLa lumière comme détective de la constitution des corps
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in Société chimique de Belgique (Ed.) Walthère Spring : Oeuvres complètes (1905)

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