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721.
722.
Shweta D. Dabhi Swati Gahlot Sheefa Mirza Medha Pandya Rakesh Rawal Vaibhav Kulshrestha Prafulla K. Jha 《Macromolecular Symposia》2024,413(1):2300086
Graphene and graphene oxide (GO) have garnered significant attention due to their exceptional properties. GO, enriched with various functional groups such as epoxy, hydroxyl, and carboxylic groups, has exhibited remarkable potential in biomedical applications. The combination of GO with metals has proven to be a promising platform for cellular imaging, with this study focusing on the preparation of diverse hybrids of GO with metal oxides (GO/MO) and their potential as anticancer agents. In this research, GO is functionalized with MOs like TiO2, Fe3O4, and Cu2O using specific chemical methods and investigated for the anticancer activity for the application as cancer therapeutic agent. The resulting GO/MO hybrids exhibits favorable thermal and mechanical properties. Moreover, their cytotoxicity against human lung cancer cells is assessed in vitro, revealing the promising anticancer activity of GO/MO hybrids. Notably, the GO/Cu2O hybrid demonstrates particularly high cytotoxicity in human lung cancer cells. 相似文献
723.
In this paper, simple relations are proposed for the calculation of Debye temperature θD and melting point Tmof II‐VI and III‐V zincblende semiconductors. Six relations are proposed to calculate the value of θD. Out of these six relations, two are based on plasmon energy data and the others on molecular weight, melting point, ionicity and energy gap. Three simple relations are proposed to calculate the value of Tm. They are based on plasmon energy, molecular weight and ionicity of the semiconductors. The average percentage deviation of all nine equations was calculated. In all cases, except one, it was estimated between 3.34 to 17.42 % for θD and between 2.37 to 10.45 % for Tm. However, in earlier correlations, it was reported between 10.59 to 33.38% for θD and 6.96 to 14.95% for Tm. The lower percentage deviation shows a significant improvement over the empirical relations proposed by earlier workers. The calculated values of θD and Tm from all equations are in good agreement with the available experimental values and the values reported by different workers. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
724.
Sajid Saikia Animesh Ghosh Angshuman Nag 《Angewandte Chemie (International ed. in English)》2023,62(33):e202307689
A phosphor emitting both white light and broad near-infrared (NIR) radiation can simultaneously provide visual inspection and early signs of rotting of food products. The broad NIR emission is absorbed by the vibrational overtones of water molecules present in food items, providing the non-invasive image contrast to assess the food freshness. Here we design a phosphor, namely, Cr3+-Bi3+-codoped Cs2Ag0.6Na0.4InCl6, that simultaneously emit warm white light and broad NIR (1000 nm) radiation with quantum yield 27 %. This dual emitter is designed by combining the features of s2-electron (Bi3+) and d3-electron (Cr3+) doping in a weak crystal field of the halide perovskite host. excitation of Bi3+, using a commercial 370 nm ultraviolet light-emitting-diodes (UV-LED), yields both the emissions. A fraction of the excited Bi3+ dopants emit the warm white light, and the other fraction transfers its energy non-radiatively to Cr3+. Then the Cr3+ de-excites emitting broad NIR emission. Temperature dependent (6.4–300 K) photoluminescence in combination with Tanabe-Sugano diagram show that the Cr3+ experiences a weak crystal field ( =2.2), yielding the NIR emission. As a proof of concept, we fabricated a panel containing 122 phosphor-converted LEDs, demonstrating its capability to inspect food products. 相似文献
725.
The hitherto unreported compounds of general structure 3,3′-(alkanediyl)bis-(2,2,2-triaryl-1-oxa-2-stiba-3-azabenzo[d]cyclohex-5-ene) have been synthesized in 48-56% yields by the cyclization of the tetrasodium salt of N,N′-bis(2-hydroxybenzyl)-1,2-diaminoethane(II) or of N,N′-bis(2-hydroxybenzyl)-1,3-diaminopropane(II*) with R3SbBr2 (R = phenyl, p-tolyl, or mesityl). The tetrasodium salts were prepared by the reactions of the corresponding amines with sodium hydride. The amines (II and II*), in turn, were obtained by the sodium borohydride reduction of N,N′-bis(salicylidene)-1,2-diaminoethane and N,N′-bis-(salicylidene)-1,3,-diaminopropane, respectively. The heterocyclic compounds are air stable and moisture insensitive. These compounds have been characterized by elemental analyses, molecular weight determinations, and by IR, far IR, 1H, and 13C NMR spectral studies. © 1996 John Wiley & Sons, Inc. 相似文献