During the political regime of the Bharatiya Janata Party (BJP), public knowledge in India has been tarnished with political colors. The BJP has used the color saffron, which is closely associated with the Indian National Flag, as a sociopolitical tool to signal patriotism, nationalism, indigenization, and decolonization. However, the government’s policies and messages focus on the self-profiting mechanisms of Hindutva ideology. According to the BJP, the notions of pre-colonial knowledge systems and patriotism are only related to the Hindu religion. Thus, public knowledge in India has been politicized through “saffronization”: the color saffron, rightwing political ideologies, and religious fundamentalism combine to create false beliefs about Indian history and culture, which then inspire and excuse hate and crime.

The adsorption and oxidation of 3,3′,5,5′-tetramethyl benzidine (TMB) on hectorite has been investigated using X-ray powder diffraction, ultraviolet-visible spectroscopy, electron spin resonance, and infrared spectroscopy. The molecule adsorbed by cation exchange at low adsorption levels and oxidized to the monomeric radical cation (yellow). At higher adsorption levels, intercalation of TMB occurred in amounts greater than the cation-exchange capacity of the hectorite, and the π-π charge-transfer complex (blue) became much more evident. The TMB monomers appeared to lie flat in the layer silicate interlayers, whereas the molecules in the charge-transfer complexes assumed a near-vertical orientation relative to the surface. The oxidation of adsorbed TMB was probably due to diffusion of O2 to the surface, because the structural Fe3+ content of the hectorite was too low to facilitate a significant quantity of direct Fe3+-TMB electron transfer.

Nine hematites and 22 goethites were synthesized by a variety of methods to obtain monomineralic samples having a range of Al substitutions and particle sizes. The second derivative of absorbance and Munsell color designations were calculated from visible reflectance spectra obtained from the dry powders. Unit-cell dimensions, Al substitution, infrared band positions, mean crystallite dimensions (MCD) from X-ray powder diffraction, and particle size from fiber-optic Doppler anemometry (FODA) were determined. Previously reported correlations between Al substitution, goethite unit-cell dimensions, and OH-stretching and -bending band positions were confirmed. For hematite, the position of the second derivative peak at ∼600 nm was negatively correlated with Al substitution (r = −.86). Munsell value and chroma were positively correlated with Al substitution (r =.94 for both), but hue was not related to Al substitution. Hue appeared to become redder, however, as particle size measured either by FODA or MCD increased. For goethite, the position of the second derivative minimum at ∼485 nm was negatively correlated with Al substitution (r = −.99). Munsell hue appeared to be related to both Al substitution and MCD perpendicular to (110), MCD110, with hues becoming redder with increasing Al substitution and yellower with increasing MCD110. Correlations between Munsell value and chroma and parameters such as Al substitution, particle size, and OH-stretching and -bending band positions were poor, but goethites synthesized by oxidation of Fe2+ solutions at room temperature had higher chromas than goethites synthesized hydrothermally from an Fe3+ system. Visually determined colors agreed well with calculated ones. Second-derivative spectra and color designations calculated from visible spectra appear to be potentially useful for quickly estimating other properties of goethite and hematite, such as Al substitution and particle size.

The crystallization kinetics of goethite were studied colorimetrically under highly alkaline conditions (pH 10.1–12.2) at temperatures from 40° to 85°C. Color changes during crystallization from fresh precipitates, plotted on a*-b* colorimetric diagrams, were used to discriminate between pure goethite and mixtures of goethite and hematite. Only the b* value increased as goethite crystallization proceeded, and even a minor increase in the a* value revealed the existence of hematite. The rate of goethite crystallization, estimated from the b* value, could be modeled by a pseudo-first-order rate law. This rate depended both on pH and on temperature. Apparent activation energies for the reactions of 56.1 kJ/mol at pH 11.7 and 48.2 kJ/mol at pH 12.2 were estimated from Arrhenius plots.

Synthetic hematites prepared in the presence of phosphate can incorporate phosphorus (P) in forms other than phosphate adsorbed by ligand-exchange on the crystal surface. To investigate the nature of such occluded P, which is also found in some natural specimens, we prepared 13 hematites by aging ferrihydrite precipitated from Fe(NO3)3-KH2PO4 solutions. The P/Fe atomic ratio of the resulting hematites ranged from 0 to 3% and all incorporated significant amounts of OH. As P content is raised, particle morphology changes from rhombohedral to spindle or ellipsoid-shaped. Despite the grainy appearance in transmission electron microscope images, X-ray diffraction data indicate that the particles are single crystals. Specific surface area ranged from 66 to 91 m2g−1, partly in micropores. The intensity of the absorption bands due to Fe3+ ligand field transition in the visible region, as measured by the second derivative of the Kubelka-Munk function, suggests that both OH and P contribute to an Fe deficiency in the structure. Such a deficiency is also apparent from the 104/113 peak intensity ratio in the X-ray diffraction patterns. The c unit-cell length increases with increasing P content. The infrared spectra exhibit four bands in the P-OH stretching region (viz., at 936, 971, 1005, and 1037 cm−1) which suggest that occluded PO4 possesses a low symmetry. Congruent dissolution of P and Fe was observed on acid treatment of the hematites, the dissolution rate being negatively correlated with the P content. All observations are consistent with the occluded P in the hematites being structural. A model is proposed where P occupies tetrahedral sites in the hematite structure, thus resulting in an Fe deficiency and facilitating proton incorporation.

The adjective χλωρός appears in the Septuagint to translate Hebrew terms that not only denote color, but state as well. In fact, in biblical Hebrew color is not a quality, but rather a “state” of the entities it describes. It is logical to wonder, then, whether it also expresses this in the Septuagint or if it denotes only color. To answer this question, it is necessary to carry out an interdisciplinary study of color and color language. The methodology followed will first study the concept of color in the Hellenistic world and in the Septuagint, as well as the cultural context in which the Septuagint translators lived. Subsequently, an approximate account of the “encyclopedic knowledge” that those translators possessed will be given, followed, finally, by a semantic analysis of χλωρός in the Septuagint. After applying this methodology, it will be shown that in the Septuagint, as in the Hellenistic world in general, natural color expresses both color and state, with color being the visual reflection of that state.

Hematite (α-Fe2O3) possesses distinct spectral properties which facilitate its identification in mineral mixtures. This paper reports the relationships between the visible diffuse reflectance (DR) spectrum and the color and crystal properties of a group of 81 natural and synthetic hematites. The visible DR spectra for powdered hematite samples diluted to 4 wt.% with BaSO4 white standard were recorded and used to calculate the corresponding Munsell colors. The second derivative of the Kubelka-Munk function of the DR was used to estimate the position and intensity of the main absorption bands, which occurred at ∼435, ∼485 and ∼545 nm. The Munsell hue ranged from 9.5P to 5.3YR and was negatively correlated with the position of the ∼545 nm band, so it became yellower as the band shifted to shorter wavelengths (higher energies). The Munsell value, which ranged from 4.9 to 8.6, and chroma, which ranged from 1.4 to 8.3, were negatively and positively correlated, respectively, with the intensity of the ∼545 nm band, the position of which exhibited a weak negative correlation with the degree of Al substitution (x). The position and intensity of this band also exhibited a weak negative correlation with the specific surface area (SSA); both, however, were uncorrelated with domain shape as measured by the ratio between the X-ray mean coherence lengths (MCLs) in the [110] and [104] directions. The properties of the ∼435 and ∼485 nm bands were unrelated to x, SSA or MCL110/MCL104. The negative relationship between the position of the ∼545 nm band and x does not support the assignment of this band to the 2(6A1) → 2(4T1g(4G)) electron pair transition (EPT), which relates to the to Fe3+−Fe3+ magnetic coupling between face-sharing octahedra. The ∼485 nm band might reflect a ‘goethitic’ structural component in Fe-defective hematites as it appears at the same wavelength as the hypothetical EPT related to Fe3+−Fe3+ magnetic coupling between edge-sharing octahedra in goethite (α-FeOOH).

Aging causes impairment of contrast sensitivity and chromatic discrimination, leading to changes in the perceptual interactions between color and luminance information. We aimed to investigate the influence of chromatic noise on luminance contrast thresholds in young and older adults. Forty participants were divided equally into Young (29.6 ± 6.3-year-old) and Elderly Groups (57.8 ± 6.6-year-old). They performed a luminance contrast discrimination task in the presence of chromatic noise maskers using a mosaic stimulus in a mosaic background. Four chromatic noise masking protocols were applied (protan, deutan, tritan, and no-noise protocols). We found that luminance contrast thresholds were significantly elevated by the addition of chromatic noise in both age groups (P < 0.05). In the Elderly group, but not the younger group, thresholds obtained in the tritan protocol were lower than those obtained from protan and deutan protocols (P < 0.05). For all protocols, the luminance contrast thresholds of elderly participants were higher than in young people (P < 0.01). Tritan chromatic noise was less effective in inhibiting luminance discrimination in elderly participants.

Many studies have substantiated the perceptual symbol system, which assumes a routine generation of perceptual information during language comprehension, but little is known about the processing format in which the perceptual information of different dimensions is conveyed simultaneously during sentence comprehension. The current study provides the first experimental evidence of how multidimensional perceptual information (color and shape) was processed during online sentence comprehension in Mandarin. We designed three consecutive sentence–picture verification tasks that only differed in the delay of the display of pictures preceded by declarative sentences. The processing was analyzed in three stages based on time intervals (i.e., 0ms, +750ms, +1500ms). The response accuracy and response time data were reported. The initial stage (i.e., ISI=0ms) attested the match effect of color and shape, but the simulated representation of color and shape did not interact. In the intermediate stage (i.e., ISI=750ms), the routinely simulated color and shape interacted, but the match facilitation was found only in cases where one perceptual information was in mismatch while the other was not. In the final stage (i.e., ISI=1500ms), the match facilitation of one particular perceptual property was influenced by a mismatch with the other perceptual property. These results suggested that multiple perceptual information presented simultaneously was processed in an additive manner to a large extent before entering into the final stage, where the simulated perceptual information was integrated in a multiplicative manner. The results also suggested that color and shape were comparable to object recognition when conjointly conveyed. In relation to other evidence from behavioral and event-related potential studies on sentence reading in the discussion, we subscribed to the idea that the full semantic integration became available over time.