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Here, we used the methanol-induced precipitation method to prepare and separate two size selected gold clusters protected by two enantiomers and racemic mixture of penicillamine ligand. The clusters materials were obtained by the reduction of HAuCl4∙3H2O salt with NaBH4 in the presence of L-penicillamine (L-pen), D-penicillamine (D-pen) and racemic mixture of penicillamine (rac-pen) as capping ligands. Two fractions were obtained with particles of about 1 nm and 2.6 nm, respectively. The average chemical formula was determined from thermogravimetric analysis (TGA). The optical properties of the samples were studied by three different methods: UV-vis spectroscopy, photoluminescence spectroscopy (PL) and circular dichroism (CD) spectroscopy. PL studies yielded the fluorescent properties of the samples. The main focus of this work, however, lies in the chirality of the particles. The CD spectra for gold clusters capped with one of the two enantiomers (D- or L-form) typical CD spectra were observed, no significant signals were detected for a racemic ligand mixture. Furthermore, gold clusters show quite large asymmetry factors (up to 1.3x10-3) in comparison to most other ligand protected clusters. These large factors and bands in the visible range of the spectrum suggest a strong chiral induction from the ligand to the metal core.

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The glass transition and non-isothermal crystallization behavior of Ge20Se70Sn10 glass prepared by the melt-quenching technique was investigated using differential scanning calorimetry (DSC) at continuous different heating rates. The structure and surface morphology of asprepared and annealed samples were characterized using X-ray diffraction (XRD) and scanning electron microscopy. The as-prepared samples showed the amorphous glassy nature, while the annealed ones are polycrystalline. Furthermore, XRD phase analysis allowed us to find the SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the annealed samples. According to the value of Avrami index (n), the crystallization process of studied composition has more than one crystal growth mechanism. In addition, the results of DSC showed that the investigated glass has only a single glass transition and double crystallization stages. Furthermore, the activation energy of transition as well as the crystallization has been determined based on different approximation methods. In addition, the experimental DSC data of the first and second crystallization peak were compared with that calculated with the Johnson–Mehl– Avrami and Sestak–Berggren SB(M, N) model. The results revealed that the SB(M, N) model is more suitable for describing the crystallization kinetics of studied glass.

The glass transition and non-isothermal crystallization behavior of Ge20Se70Sn10 glass prepared by the melt-quenching technique was investigated using differential scanning calorimetry (DSC) at continuous different heating rates. The structure and surface morphology of asprepared and annealed samples were characterized using X-ray diffraction (XRD) and scanning electron microscopy. The as-prepared samples showed the amorphous glassy nature, while the annealed ones are polycrystalline. Furthermore, XRD phase analysis allowed us to find the SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the annealed samples. According to the value of Avrami index (n), the crystallization process of studied composition has more than one crystal growth mechanism. In addition, the results of DSC showed that the investigated glass has only a single glass transition and double crystallization stages. Furthermore, the activation energy of transition as well as the crystallization has been determined based on different approximation methods. In addition, the experimental DSC data of the first and second crystallization peak were compared with that calculated with the Johnson–Mehl– Avrami and Sestak–Berggren SB(M, N) model. The results revealed that the SB(M, N) model is more suitable for describing the crystallization kinetics of studied glass.

The glass transition and non-isothermal crystallization behavior of Ge20Se70Sn10 glass prepared by the melt-quenching technique was investigated using differential scanning calorimetry (DSC) at continuous different heating rates. The structure and surface morphology of asprepared and annealed samples were characterized using X-ray diffraction (XRD) and scanning electron microscopy. The as-prepared samples showed the amorphous glassy nature, while the annealed ones are polycrystalline. Furthermore, XRD phase analysis allowed us to find the SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the annealed samples. According to the value of Avrami index (n), the crystallization process of studied composition has more than one crystal growth mechanism. In addition, the results of DSC showed that the investigated glass has only a single glass transition and double crystallization stages. Furthermore, the activation energy of transition as well as the crystallization has been determined based on different approximation methods. In addition, the experimental DSC data of the first and second crystallization peak were compared with that calculated with the Johnson–Mehl– Avrami and Sestak–Berggren SB(M, N) model. The results revealed that the SB(M, N) model is more suitable for describing the crystallization kinetics of studied glass.

The glass transition and non-isothermal crystallization behavior of Ge20Se70Sn10 glass prepared by the melt-quenching technique was investigated using differential scanning calorimetry (DSC) at continuous different heating rates. The structure and surface morphology of asprepared and annealed samples were characterized using X-ray diffraction (XRD) and scanning electron microscopy. The as-prepared samples showed the amorphous glassy nature, while the annealed ones are polycrystalline. Furthermore, XRD phase analysis allowed us to find the SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the annealed samples. According to the value of Avrami index (n), the crystallization process of studied composition has more than one crystal growth mechanism. In addition, the results of DSC showed that the investigated glass has only a single glass transition and double crystallization stages. Furthermore, the activation energy of transition as well as the crystallization has been determined based on different approximation methods. In addition, the experimental DSC data of the first and second crystallization peak were compared with that calculated with the Johnson–Mehl– Avrami and Sestak–Berggren SB(M, N) model. The results revealed that the SB(M, N) model is more suitable for describing the crystallization kinetics of studied glass.

The glass transition and non-isothermal crystallization behavior of Ge20Se70Sn10 glass prepared by the melt-quenching technique was investigated using differential scanning calorimetry (DSC) at continuous different heating rates. The structure and surface morphology of asprepared and annealed samples were characterized using X-ray diffraction (XRD) and scanning electron microscopy. The as-prepared samples showed the amorphous glassy nature, while the annealed ones are polycrystalline. Furthermore, XRD phase analysis allowed us to find the SnSe2, GeSe2, Ge4Se9 and Sn0.5 SeGe0.5 phases in the annealed samples. According to the value of Avrami index (n), the crystallization process of studied composition has more than one crystal growth mechanism. In addition, the results of DSC showed that the investigated glass has only a single glass transition and double crystallization stages. Furthermore, the activation energy of transition as well as the crystallization has been determined based on different approximation methods. In addition, the experimental DSC data of the first and second crystallization peak were compared with that calculated with the Johnson–Mehl– Avrami and Sestak–Berggren SB(M, N) model. The results revealed that the SB(M, N) model is more suitable for describing the crystallization kinetics of studied glass.

The aim of this study is to evaluate the effect of different concentrations of citral on glutathione (GSH), nitric oxide (NO), lipid peroxide (LPO) and vitamin C. Also, the protective effect of N. sativa was studied. Fertilized eggs of the chick Gallus domesticus were divided into control or experimental groups which received three different concentrations of citral (50, 100 and 200 μM), N. sativa extract (5 μl) or a combination of N. sativa extract with citral. Citral and N. sativa groups decreased GSH & vitamin C and NO, while increased LPO. Co-treatment with citral and N. sativa increased GSH & vitamin C and decreased LPO levels. Citral induced oxidative stress by inhibiting RA synthesis. The limited mitigative properties of N. sativa are attributed to either its antineoplastic properties, the high levels of oxidative stress provoked by citral and above its antioxidative capacity or the low administered dose.

The aim of this study is to evaluate the effect of different concentrations of citral on glutathione (GSH), nitric oxide (NO), lipid peroxide (LPO) and vitamin C. Also, the protective effect of N. sativa was studied. Fertilized eggs of the chick Gallus domesticus were divided into control or experimental groups which received three different concentrations of citral (50, 100 and 200 μM), N. sativa extract (5 μl) or a combination of N. sativa extract with citral. Citral and N. sativa groups decreased GSH & vitamin C and NO, while increased LPO. Co-treatment with citral and N. sativa increased GSH & vitamin C and decreased LPO levels. Citral induced oxidative stress by inhibiting RA synthesis. The limited mitigative properties of N. sativa are attributed to either its antineoplastic properties, the high levels of oxidative stress provoked by citral and above its antioxidative capacity or the low administered dose.