Results 91 to 100 of about 2,245 (216)
Advanced Energy Materials, Volume 16, Issue 31, 19 August 2026.This comprehensive review highlights surface acidity engineering as a versatile strategy to modulate surface charge and boost catalytic performance in functional oxides. It explores recent advances in practical implementation, structural reconstruction approaches, and mechanistic origins from diverse complementary viewpoints.
Gyu Rac Lee, Harry L. Tuller
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Discussiones Mathematicae Graph Theory, 1995 There are gained explicit formulas for chromatic polynomials of cacti, \(n\)-gon trees and unicyclic graphs with \(p\)-cycle, respectively.
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Chromatic partitions of a graph
Discrete Mathematics, 1989 The chromatic partition number \(\chi_ k(G)\) (k\(\geq 1)\) of a graph G is defined to be the minimum number of colours needed in a \(P_ k\)- colouring of G. The following are the main results: (1) For any graph G of order p, \[ \frac{p}{M_ k}\leq \chi_ k(G)\leq \{\frac{p-M_ k}{k}\}+1\quad and\quad -\frac{p}{\beta_ 0k}\leq \chi_ k(G)\leq \{\frac{p ...
E. Sampathkumar 0001 +1 more
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Barium, zinc and strontium yellows in late 19th–early 20th century oil paintings
Heritage Science, 2017 This work focuses on the study of the 19th century yellow chromate pigments based on barium (BaCrO4), zinc (4ZnCrO4·K2O·3H2O) and strontium (SrCrO4). These pigments, which are reported to shift in hue and darken, have been found in 19th century artworks.
Vanessa Otero +5 more
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Chromaticities of Lovibond Glasses
Journal of the Optical Society of America, 1947 This paper reports by means of a series of graphs the chromaticity coordinates of certain Lovibond unit glasses and of pairs of such glasses in combination with an illuminant of color temperature 2842°K (Illuminant A). The chromaticities were computed according to the 1931 I.C.I. standard observer and coordinate system.
G W, HAUPT, F L, DOUGLAS
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Effect of ph on corrosion inhibition of mild-steel by chromates
, 1993 The paper outlines the effect of pH on corrosion inhibition of mild steel by chromates using radioactive tracer technique. It shows that Cr-uptake is more in the acidic region, less in the neutral zone and the least in the alkaline region.
Bahadur, Aruna
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Chemical Engineering Transactions, 2015 Chromium is found in the environment mainly as hexavalent chromium, Cr(VI), and the trivalent form, Cr(III). Cr(VI) is carcinogenic and mutagenic to living organisms including humans whereas trivalent chromium is 1,000 times less toxic than Cr(VI).
L.A. Kaimbi, E.M.N. Chirwa
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Chemical Engineering Transactions, 2017 One of the most important factors in the redox state of chromium in solution is pH, which, according to its value, can lead to oxidation of Chromium (III) to Chromium (VI).
C. Concha Castro +5 more
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Discussiones Mathematicae Graph Theory, 2001 Let \(\tau(G)\) denote the number of vertices in a longest path of a graph \(G\). The \(n\)th detour number \(\chi_n(G)\) of a graph \(G\) is the minimum number of colours required to colour the vertices of \(G\) such that no path with more than \(n\) vertices is monocoloured. It is shown that the path partition conjecture, formulated by P. Mihók (see \
Frank Bullock, Marietjie Frick
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