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Balakina A. A. Mumyatova V. A. Pliss E. M. Terent’ev A. A. Sen’ V. D. 《Russian Chemical Bulletin》2018,67(11):2135-2140
Russian Chemical Bulletin - The cytotoxicity and antioxidant properties of water-soluble (at physiological pH) chitosan- (poly)nitroxides (CPNs) containing pyrroline-based nitroxide and having... 相似文献
925.
Gregory K. Smith Sen Lin Wenzhen Lai Abhaya Datye Daiqian Xie Hua Guo 《Surface science》2011,605(7-8):750-759
Recent experiments suggested that PdZn alloy on ZnO support is a very active and selective catalyst for methanol steam reforming (MSR). To gain insight into MSR mechanism on this catalyst, plane-wave density functional theory calculations were carried out on the initial steps of MSR on both PdZn and ZnO surfaces. Our calculations indicate that the dissociation of both methanol and water is highly activated on flat surfaces of PdZn such as (111) and (100), while the dissociation barriers can be lowered significantly by surface defects, represented here by the (221), (110), and (321) faces of PdZn. The corresponding processes on the polar Zn-terminated ZnO(0001) surfaces are found to have low or null barriers. Implications of these results for both MSR and low temperature mechanisms are discussed. 相似文献
926.
Xiao‐Qing Zhao Yi‐Yan Wang Dong‐Xu Bao Fen‐Hang Zhang Wei Wu Fu‐Sen Xu Qiu‐Hong Zhang Yun‐Chun Li 《应用有机金属化学》2019,33(11)
Six novel decanuclear clusters with formula of {[Fe8Ln2(O)4(OH)4(EtO)2(dhbp)4(dhbpH)2(piv)6]·4EtOH} (Ln = Y ( 1 ), Gd ( 2 ), Tb ( 3 ), Dy ( 4 ), Ho ( 5 ), Er ( 6 ), dhbpH2 = 6,6′‐dihydroxyl‐2,2′‐bipyridine, Hpiv = pivalic acid, EtOH = ethanol) have been synthesized and characterized. Single‐crystal and powder X‐ray diffraction analyses reveal that complexes 1 – 6 are isostructural and show a sandwich‐like FeIII8LnIII2 structure, in which the [Ln2] unit is sandwiched by two planar [Fe4] units. Magnetic properties of complexes 1 – 6 have been investigated and display dominant antiferromagnetic interactions, thereinto, complexes 4 and 6 display weak ferromagnetic behaviors associated with LnIII ions, while others are antiferromagnetic‐like features. Furthermore, complex 4 (FeIII8DyIII2) shows temperature/frequency‐dependent ac signals with an energy barrier of 4.1 K, indicating that complex 4 should be a single‐molecule magnet (SMM) 相似文献
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Effect of configuration symmetry on synchronization in a Van der Pol ring with nonlocal interactions
Nonlinear Dynamics - This paper discusses the influence of configuration symmetry on synchronization of coupled Van der Pol oscillators in a ring, where the inherent symmetry in an even number ring... 相似文献
930.
Understanding the Origins of Nucleophilic Hydride Reactivity of a Sodium Hydride–Iodide Composite 下载免费PDF全文
Zonghan Hong Derek Yiren Ong Dr. Subas Kumar Muduli Dr. Pei Chui Too Guo Hao Chan Dr. Ya Lin Tnay Prof. Shunsuke Chiba Dr. Yusuke Nishiyama Prof. Hajime Hirao Prof. Han Sen Soo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):7108-7114
Sodium hydride (NaH) has been commonly used as a Brønsted base in chemical syntheses, while it has rarely been employed to add hydride (H?) to unsaturated electrophiles. We previously developed a procedure to activate NaH through the addition of a soluble iodide source and found that the new NaH–NaI composite can effect even stereoselective nucleophilic hydride reductions of nitriles, imines, and carbonyl compounds. In this work, we report that mixing NaH with NaI or LiI in tetrahydrofuran (THF) as a solvent provides a new inorganic composite, which consists of NaI interspersed with activated NaH, as revealed by powder X‐ray diffraction, and both solid‐state NMR and X‐ray photoelectron spectroscopies. DFT calculations imply that this remarkably simple inorganic composite, which is comprised of NaH and NaI, gains nucleophilic hydridic character similar to covalent hydrides, resulting in unprecedented and unique hydride donor chemical reactivity. 相似文献