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61.
Fereshteh Malek Mohammad Bagher Kazemi Balgeshir 《Mediterranean Journal of Mathematics》2013,10(2):1023-1033
In this paper we introduce the notion of slant submanifold of an almost contact metric 3-structure manifold. We give some examples and characterize these submanifolds. Moreover, Sasakian slant submanifolds of an almost contact 3-structure manifold are defined and studied. We also establish a sharp inequality including the squared mean curvature and Ricci curvature of a Sasakian slant submanifold. 相似文献
62.
Koji Kimura Koichi Hayashi Lada V. Yashina Naohisa Happo Takumi Nishioka Yuta Yamamoto Yoshihiro Ebisu Toru Ozaki Shinya Hosokawa Tomohiro Matsushita Hiroo Tajiri 《Surface and interface analysis : SIA》2019,51(1):51-55
We performed X-ray fluorescence holography measurements on an In-doped Bi2Se3 topological insulator and obtained an in-plane atomic image in the vicinity of In. We found that atomic images at the positions of the first nearest neighbors (NNs) are very weak whereas those at the positions of the second and the third NNs are relatively strong. On the basis of the fact that In is half of the atomic number of Bi, we attributed the origin of this feature to the clustering of the In atoms in the Bi plane. We calculated the intensity of the atomic images and confirmed that the formation of In cluster results in a decrease by 30% in the first NN atomic image intensity. However, the decrease in the magnitude is not enough to explain the experimental results, suggesting another contribution such as the lattice distortions. The effect of the lattice distortion on the atomic image intensity is discussed on the basis of the simulation including the positional fluctuation of In atoms. 相似文献
63.
Samanehsadat Sharifi Malek Taher Maghsoudlou Nourallah Hazeri Faramarz Rostami‐Charati 《中国化学会会志》2019,66(10):1347-1355
In this research, the green synthesis of chromen derivatives in good yields is described via three‐component reactions of 4‐hydroxycumarine, aldehydes or ketones, and methyl ketones in the presence of KF/clinoptilolite nanoparticles (KF/CP‐NPs) under solvent‐free conditions at 50°C in low time. The present methodology suggests some advantages such as low reaction time, easy and simple procedure, green method, inexpensive catalyst, high yield of product, and existence of different substrates for performing these reactions. In addition, it should be mentioned that antioxidant activity was studied for some prepared compounds, such as 4a–4d, by DPPH radical trapping and reducing potential tests of ferric ion and then comparing results with TBHQ and BHT as synthetic antioxidants. In this study, compounds 4c was shown to have moderate DPPH radical trapping, and compounds 4b and 4d displayed good reducing power of ferric ion. 相似文献
64.
Faroughi Niya Homayoun Hazeri Nourallah Fatahpour Maryam Maghsoodlou Malek Taher 《Research on Chemical Intermediates》2020,46(7):3651-3666
Research on Chemical Intermediates - A novel magnetically heterogeneous nanocatalyst has been successfully synthesized via the immobilization of piperazine on tris (hydroxymethyl)... 相似文献
65.
Positivity - This paper is devoted to the study of efficient elements for set-valued maps. We propose two new notions of relative weak $$\epsilon $$ -efficient element and strict relative weak... 相似文献
66.
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68.
AbstractIn recent years the electro-optic polymers emerged as an important branch of material science. This growth and interest is fundamentally motivated by practical application of these materials in second-order nonlinear optics and in waveguiding configuration. Indeed, these materials marry excellent optical quality of amorphous σ bonded polymers with enhanced first hyperpolarizability of imbedded organic nonlinear optical molecules. Although a big progress was achieved with them, concerning particularly the science, understanding and applications, some problems remain still incompletely solved, particularly the stability of induced polar order by the application of external electric field and the molecule aggregation. In this review paper we recall techniques of thin film fabrication, poling, characterization of NLO properties and discuss more precisely problems of molecule aggregation as well as the temporal decay of polar order. A novel 3D second-order NLO chromophores, namely the [2] paracyclophanes, which may help to limit the aggregation, are proposed. We show, in particular, that this molecule can be poled in doped PMMA thin films. Practical applications of electro-optic polymers are also reviewed and discussed. 相似文献
69.
Malek Taher Maghsoodlou Sayyed Mostafa Habibi Khorassani Lotfali Saghatforoush Farhad Maghfuri Ghasem Marandi Roya Kabiri 《Journal of heterocyclic chemistry》2008,45(1):289-293
High hindrance Hexa tert‐butoxy carbonyl dipyrrolophenanthroline and helical dihydropyrrolophen‐anthroline compounds were prepared from reactions between di tert‐butyl acetylenedicarboxylate and 1,10‐phenanthroline in polar solvents media. 相似文献
70.
Abdul Malek Yanrong Xue Xu Lu 《Angewandte Chemie (International ed. in English)》2023,62(40):e202309854
In the pursuit of long-term stability for oxygen evolution reaction (OER) in seawater, retaining the intrinsic catalytic activity is essential but has remained challenging. Herein, we developed a NixCryO electrocatalyst that manifested exceptional OER stability in alkaline condition while improving the activity over time by dynamic self-restructuring. In 1 M KOH, NixCryO required overpotentials of only 270 and 320 mV to achieve current densities of 100 and 500 mA cm−2, respectively, with excellent long-term stability exceeding 475 h at 100 mA cm−2 and 280 h at 500 mA cm−2. The combination of electrochemical measurements and in situ studies revealed that leaching and redistribution of Cr during the prolonged electrolysis resulted in increased electrochemically active surface area. This eventually enhanced the catalyst porosity and improved OER activity. NixCryO was further applied in real seawater from the Red Sea (without purification, 1 M KOH added), envisaging that the dynamically evolving porosity can offset the adverse active site-blocking effect posed by the seawater impurities. Remarkably, NixCryO exhibited stable operation for 2000, 275 and 100 h in seawater at 10, 100 and 500 mA cm−2, respectively. The proposed catalyst and the mechanistic insights represented a step towards realization of non-noble metal-based direct seawater splitting. 相似文献