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551.
Fatma K. Canitez Mustafa S. Yavuz Ramazan Ozturk 《Journal of nanoparticle research》2011,13(12):7219-7228
In this study, the meso-tetra (p-hydroxyphenyl) porphyrin and meso-tetra (m-hydroxyphenyl) porphyrin were coated on to gold nanoparticles (AuNPs) via thioacetate anchors which easily dissociate to
form S–Au bonds. 4-tert-butyl phenyl thioacetate-AuNPs were prepared and used as a monodentate passivant to control the size of the tetradentate
porphyrin-AuNPs. The porphyrin-coated AuNPs were characterized by UV–Vis, TEM, XRD, and XPS analyses. The tetradentate porphyrin-AuNPs
size is within a range of 5–15 nm in diameter with exotic shapes. The plausible network formation for AuNP@p-TPP-SAc and the capping structure of the AuNP@m-TPP-SAc have been suggested. 相似文献
552.
Fatma?UlusalEmail authorView authors OrcID profile Ebru?Erünal Bilgehan?Güzel 《Journal of nanoparticle research》2018,20(8):219
A well-dispersed green Pd/SBA-15 catalyst with an average size of 13.7 nm and 492.6 m2/g BET surface area is prepared via supercritical fluid deposition method with a new bipyridyl precursor that enables reduction at mild conditions at 80 °C and 17.2 MPa. The catalytic performance of Pd/SBA-15 prepared using scCO2 with hydrogen reduction was assessed for Suzuki–Miyaura coupling reaction of bromobenzene and phenylboronic acid that was chosen as a model coupling reaction. The catalyst was tested in six different solutions and in three organic and inorganic bases during reactions. In general, the effect of bases is investigated when solvents are held constant and K2CO3 appears to have the best results in the activity studies used. For each of the 3 bases used, the highest catalytic activity was reached as the result of the solvent system being ethanol/water (1:1). The highest catalytic conversion was obtained in the ethanol-K2CO3 solvent-base pair. The catalyst synthesized in this study exhibited high activities and TON value was found as 160.8 at room temperature. 相似文献
553.
554.
Seda Keskin Eda Acikgoz Fatma Yilmaz Ertürk Murat Cetin Ragbetli Halil Ozkol 《Photochemistry and photobiology》2023,99(1):132-136
This study aims to evaluate the influences of ultraviolet radiation A and B ( UVA + B) exposure on the liver and heart organs of albino rats. Female Wistar Albino rats, whose hair of the dorsal skin was shaved, were exposed to a combined UVA + B radiation for 2 h/day, for 4 weeks in order to be compared with the control group. Histopathological findings in vital organs (liver and heart) were evaluated. Tissues were fixed in 10% buffered formalin (pH = 7.2) and embedded in paraffin. The histopathological findings were examined on the H&E stained sections with light microscopy. The results show that the liver and the heart were injured in the UVA + B group. Liver tissue in the UVA + B group showed minimal vacuolation, enlargement of hepatocytes and bile duct proliferation, and the heart tissue showed hibernomas; uniform large cells resembling brown fat with coarsely granular to multivacuolated cytoplasm that is eosinophilic or pale with a small central nucleus. The number of hibernoma cases was significantly higher in the UVA + B group compared with the control group (P = 0.021). The control group showed normal liver and heart histology with normal adipose tissue in the pericardium. As a result, UVA + B exposure has toxic effects, especially on the liver and the heart of Wistar albino rats. UV radiation may cause such adverse effects in humans. Therefore, protection against the harmful effects of UV radiation is of significant importance for skin and organs. 相似文献
555.
Hayam Osman Taha Atef M. El Mahdy Fatma El Sayed El Shemy Mohammed Mohammed Hassan 《International journal of quantum chemistry》2023,123(3):e27023
Hydrogen is regarded as one of the most potential sustainable energy sources in the future. Applications include transportation. Still, the event of materials for its storage is difficult notably as a fuel in vehicular transport. Nanocones are a promising hydrogen storage material. Silicon, germanium, and tin carbide nanocones have recently been proposed as promising hydrogen storage materials. In the present study, we have investigated the hydrogen storage capacity of and nanocones functionalized with Ni. The functionalized Ni atom are found to be adsorbed on and with an adsorption energy of −5.56, −6.70, and −4.25 eV. The functionalized , and bind up to seven, six and four molecules of hydrogen with the adsorption energy of (−0.34, −0.35, and −0.26 eV) and an average desorption temperature of around 434, 447, and 332 K (ideal for fuel cell applications). The SiC, GeC, and SnC nanocones systems exhibit a maximum gravimetric storage capacity of 12.51, 7.78, and 4.08 wt%. We suggested that Ni SiCNC and Ni GeCNC systems can act as potential H2 storage device materials because of their higher H2 uptake capacity as well as their stronger interaction with adsorbed hydrogen molecules than Ni SnCNC systems. The hydrogen storage reactions are characterized in terms of the charge transfer, the partial density of states, the frontier orbital band gaps, and isosurface plots. And electrophilicity are calculated for the functionalized and hydrogenated and nanocones. 相似文献