On the yellow coloration of faded photographic prints

1864 ◽  
Vol 27 (185) ◽  
pp. 546-547
Author(s):  
M. Carey Lea
Keyword(s):  
Yellow Coloration

Nanocomposite synthesis by thermolysis of [Ag(hfac)(COD)] in amorphous polystyrene

2012 ◽  
Vol 19 (2) ◽  
pp. 195-197 ◽  
Author(s):  
Gianfranco Carotenuto ◽  
Mariano Palomba ◽  
Luigi Nicolais
Keyword(s):  
Polymer Matrix ◽  
Nanocomposite Films ◽  
Numerical Density ◽  
Silver Particles ◽  
X Ray ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Yellow Coloration ◽  
Color Filters ◽  
Silver Atoms

AbstractLightfast color filters (intensively and brightly colored) can be easily produced by dying optical plastics with the surface plasmon resonance (SPR) of metal nanoparticles such as silver and gold. Here, color filters based on silver nanoparticles embedded in amorphous polystyrene have been prepared by dissolving and thermally decomposing (1,5-cyclooctadiene)(hexafluoro-acetylacetonate)silver(I) in amorphous polystyrene. The metal precursor quickly decomposes (10 s, at 180°C), leading to silver atoms that clusterize and produce a non-aggregated dispersion of silver particles in the polymer matrix. The intensity of the yellow coloration due to the SPR of nanoscopic silver can be widely tuned simply by varying the cluster numerical density in the polymer matrix that depends on the silver precursor concentration. The obtained nanocomposite films have been characterized by X-ray power diffraction, transmission electron microscopy, and UV-Vis spectroscopy.

Tunable Red-Yellow Coloration of β-FeOOH Pigments by Coating and Controlling Morphology

2017 ◽  
Vol 17 (5) ◽  
pp. 3424-3429
Author(s):  
JiYeon Yun ◽  
Ri Yu ◽  
Sungjin Park ◽  
Jae-Hwan Pee ◽  
YooJin Kim
Keyword(s):  
Yellow Coloration

scholarly journals The origin of 2.78 eV emission and yellow coloration in bulk AlN substrates

2009 ◽  
Vol 95 (26) ◽  
pp. 262104 ◽  
Author(s):  
A. Sedhain ◽  
L. Du ◽  
J. H. Edgar ◽  
J. Y. Lin ◽  
H. X. Jiang
Keyword(s):  
Yellow Coloration

scholarly journals III. A contribution to the study of the yellow colouring matter of the urine

1894 ◽  
Vol 55 (331-335) ◽  
pp. 394-407 ◽  
Keyword(s):  
Absorption Spectra ◽  
Spectroscopic Properties ◽  
Yellow Pigment ◽  
Chemical Methods ◽  
Distinctive Character ◽  
Yellow Coloration ◽  
Normal Urine ◽  
The Individual

The uncertainty which still surrounds the origin of a phenomenon so familiar as the yellow coloration of the urine bears eloquent testimony to the difficulties which beset the investigation, by ordinary chemical methods, of such substances as the urinary pigments, and to the importance of the part which the spectroscope has played in the acquisition of such knowledge of them as we possess. Indeed, our acquaintance with the individual pigments is proportional to the distinctive character of their absorption spectra, rather than to the time which has elapsed since they first attracted attention; and in not a few modern works doubt is thrown upon the very existence of a distinct yellow pigment, having negative spectroscopic properties, but to which normal urine owes its characteristic tint, the chief part in the coloration of the excretion being assigned to urobilin.

scholarly journals Variations of Chlorophyll Content at Abies alba and Nepeta pannonica Species According to Phenophase and Harvesting Area

2019 ◽  
Vol 52 (1) ◽  
pp. 74-78
Author(s):  
S. Buhăianu ◽  
Doina Carmen Jităreanu
Keyword(s):  
Chlorophyll Content ◽  
Chlorophyll A ◽  
Photosynthetic Pigments ◽  
Photosynthetic Activity ◽  
Abies Alba ◽  
Chlorophyll B ◽  
Green Color ◽  
Yellow Coloration ◽  
Chlorophyll A And B ◽  
Chlorophyll A Content

Abstract Chlorophylls from plants are photosynthetic pigments. Their quantity offers valuable informations about photosynthetic activity, growing and developing of plants. Photosynthetic pigments decrease quantitatively during senescence process or in stress conditions. The present study has been realized in laboratory conditions with material harvested from spontaneous flora. The purpose of this research was the investigation of variations of chlorophyll content from samples of biological material collected from Nepeta pannonica L. and Abies alba Mill. plants, from Câmpulung Moldovenesc and Cacica areas, Suceava county, Romania. The targeted phenophases were growth and flowering. There were realized acetonic extracts from samples for spectrophotometric determinations. Obtained data were processed to estabilish chlorophyll a and b content. There were observed that at Abies alba species, from both locations, the chlorophyll a content grew during flowering phenophase, while the chlorophyll b content had little variations. At Nepeta pannonica species, the chlorophyll a and b content decreased visibly during the flowering, due to stress. Leaves of plants from this species presented a intense green color in the growing phenophase, while during flowering phenophase they had a purple or yellow coloration. Obtained results revealed a different dynamics of chlorophyll content at studied species.

Involvement of Cyclic Adenosine Monophosphate in the Regulation of Pupal Color Adaptation of the Butterfly, Inachis io

1997 ◽  
Vol 52 (3-4) ◽  
pp. 255-258 ◽  
Author(s):  
Gerhard Starnecker
Keyword(s):  
Cyclic Adenosine Monophosphate ◽  
Adenosine Monophosphate ◽  
Intracellular Camp ◽  
Dependent Manner ◽  
Color Adaptation ◽  
Yellow Color ◽  
Pde Inhibitors ◽  
Inachis Io ◽  
Yellow Coloration ◽  
Entire Central Nervous System

AbstractIn the butterfly Inachis io, a pupal melanization reducing factor (PMRF) which is located throughout the entire central nervous system controls the intensity of pigmentation of pupal cuticle depending on the background color of the pupation site. PMRF does not only reduce melanization but, in addition, enhances lutein incorporation in a dose-dependent manner to form pupae with yellow color on bright backgrounds.The present paper reports on the effects on pupal pigmentation caused by cyclic nucleo­ tides and phosphodiesterase (PDE) inhibitors which prevent degradation of cyclic nucleo­ tides. The injection of cAMP did not alter pupal coloration whereas its membrane-permeable analog dibutyryl-cAMP mimicked dose-dependently PMRF activity. Thus, pupae of reduced melanization and, in addition, enhanced yellow coloration were formed. This indicates that an increased intracellular cAMP level is capable of mediating PMRF effect. Also, the injection of the PDE inhibitor isobutylmethylxanthine (IBMX) caused dose-dependently pupae of reduced melanization and enhanced lutein incorporation.Theophylline (another PDE inhibitor) was only slightly effective (23% inhibition of melanization) at the highest dose compared to IBMX. The injection of cGMP and its analog dibutyryl-cGMP exhibited no melanization reducing effect.Extracts of abdominal ganglia (AG) which contained PMRF activity caused significantly brighter pupae when injected in combination with IBMX. However, this stimulation by IBMX became no longer effective at higher AG doses. Therefore, the present results are suggestive of an involvement of cAMP as a second messenger in the action of PMRF on pupal color adaptation.

A note on canary coloration of wool in Ghokla sheep as influenced by restricted frequency of access to water

1978 ◽  
Vol 90 (3) ◽  
pp. 641-642
Author(s):  
M. Singh ◽  
T. More
Keyword(s):  
Water Intake ◽  
Physiological Stress ◽  
Nutritional Deficiency ◽  
Adaptive Mechanism ◽  
Access To Water ◽  
Yellow Coloration ◽  
Cutaneous Evaporation ◽  
Body Heat ◽  
Indian Sheep

Yellowing of wool as a function of physiological stress caused by nutritional deficiency in the feed of sheep (Das, 1965) though not confirmed by subsequent studies (Singh et al. 1977) evoked interest in the role of physiological stress in causing canary staining of wool. Restricted water intake as is generally the case with sheep in arid or even semiarid regions during summer, imposes considerable physiological stress. Furthermore, canary coloration is thought to be a sequel to an adaptive mechanism to hot and humid conditions in Indian sheep which have a greater reliance on cutaneous evaporation for dissipating body heat (Acharaya & Singh, 1976). It was, therefore, decided to study the influence, if any, of restricting access to water on the canary coloration of wool (non-scourable yellow coloration of the autumn clip) in the stain-susceptible Chokla sheep

scholarly journals Characidium xanthopterum (Ostariophysi: Characiformes: Crenuchidae): a new species from the Central Brazilian Plateau

2008 ◽  
Vol 6 (2) ◽  
pp. 169-174 ◽  
Author(s):  
Luiz G. G. Silveira ◽  
Francisco Langeani ◽  
Weferson J. da Graça ◽  
Carla S. Pavanelli ◽  
Paulo A. Buckup
Keyword(s):  
New Species ◽  
Color Pattern ◽  
The Body ◽  
Ontogenetic Change ◽  
Yellow Coloration ◽  
Deep Yellow ◽  
First Time ◽  
A New Species

Characidium xanthopterum is described from tributaries of the upper rio Paraná and upper rio Tocantins basins, in the Central Brazilian Plateau, Goiás State, Brazil. The new species is diagnosed among congeners by the absence of dark bars on the sides of the body in adult specimens, and by the deep yellow coloration in all fins. Ontogenetic change of color pattern is recorded for the first time for Characidium species. Specimens smaller than 32 mm SL possess dark bars on body. These bars disappear with growth between 32 and 35 mm SL, and are always absent in individuals larger than 35 mm SL.

Mécanisme d'apparition de la coloration jaunâtre dans les poudres de sulfate stanneux

1977 ◽  
Vol 55 (19) ◽  
pp. 3425-3428
Author(s):  
G. Verville
Keyword(s):  
Charge Transfer ◽  
Spectrophotometric Study ◽  
Charge Transfer Complexes ◽  
Yellow Coloration ◽  
Hydrolysis Of

A spectrophotometric study of stannous sulphate powders has enabled the mechanism of the yellow coloration of these powders to be defined. It is shown that the yellow coloration results from the formation of charge transfer complexes of the type 1Sn(II)–4Sn(IV) in a film of adsorbed and acidified water which surrounds some stannous sulphate particles. The charge transfer complexes are formed by the adsorption of Sn2+•xH2O or SnHSO4+ ions onto the surface of colloidal Sn(OH)4•xH2O that is formed by the oxidation and hydrolysis of the stannous sulphate.

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