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971.
This work focuses on humidity sensor based Ni(OH)2 nanoparticles. The sonochemical method was employed to prepare nanoparticles and impedance analysis was used to characterize sensitivity, response, and recovery time of the prepared sensor. The Ni(OH)2 sensor was found to have high sensitivity and fast response/recovery time to humidity, and its impedance changed approximately two orders of magnitude from about 2.01 MΩ in dry air 20% RH (relative humidity) to 0.0258 MΩ in 90% RH air. Our results demonstrate the potential application of Ni(OH)2 nanoparticles for fabricating high performance humidity sensors. 相似文献
972.
《Journal of Coordination Chemistry》2012,65(11):1759-1764
A new mononuclear nickel(II) complex incorporating a Schiff-base ligand, [NiL2](DMF)4 (HL = 2′-(3,5-dibromo-2-hydroxybenzylidene)-3,5-dihydroxybenzoylhydrazide), has been synthesized and characterized by IR, UV-Vis, elemental analysis and X-ray crystal structure analysis. HL is an anionic tridentate ligand. The nickel atom is hexacoordinated with two oxygen atoms from keto group and two oxygen atoms from hydroxy group and two nitrogen atoms from amide, with the two nitrogen atoms occupying the axial positions forming a distorted octahedral coordination sphere. 相似文献
973.
M.S. BoonW.P. Serena Saw M. Mariatti 《Journal of magnetism and magnetic materials》2012,324(5):755-760
The fabrication of flexible epoxy thin film composites was investigated in this study. Neat epoxy with a resin-to-hardener ratio of 100:32 exhibits higher tensile properties and thermal stability than neat epoxy with a resin-to-hardener ratio of 100:45. In addition, the thermal stability of epoxy composites decreased as the NiZn ferrite content in the epoxy was increased. This result could be caused by the catalytic effect of ferrite. Vibration sample magnetometer results revealed the ferrimagnetic behavior of the ferrite-filled epoxy composites. The degree of saturation magnetization of the epoxy composites increased with the addition of NiZn ferrite nanoparticles. Dielectric tests were performed at room temperature and at frequencies ranging from 104 Hz to 106 Hz. These findings indicate that the dielectric constant and the dielectric loss are dependent on the filler concentration and test frequency. 相似文献
974.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(33):10081-10084
β,β‐Disubstituted vinyl sulfones were obtained with complete regio‐ and stereocontrol in a multicomponent reaction involving alkynes, organoboronic acids, and sulfonyl chlorides in the presence of a nickel catalyst. The reaction proceeds via sulfonyl radicals generated in situ under mild reaction conditions. 相似文献
975.
A NiCl2-catalyzed isocyanide insertion reaction of anilines bearing another nucleophile functional group utilizing TEMPO as oxidant in isopropyl ethanoate (IPA) or THF has been reported. This simple and general method could afford 2-aminobenzimidazole, 2-aminobenzothiazole, 2-aminobenzoxazole, as well as 2-aminobenzo[d][1,3]oxazine in moderate to excellent yields (up to 95% yield). 相似文献
976.
Felora Heshmatpour Saeed Rayati Mona Afghan Hajiabbas Bernhard Neumüller 《无机化学与普通化学杂志》2011,637(9):1224-1228
A tetrahedrally‐distorted square‐planar nickel(II) complex of tetradentate Schiff base ligand derived from 2‐hydroxypropiophenone and 2,2′‐dimethylpropandiamine [bis(2‐hydroxypropiophenone)2,2′‐dimethylpropylenediimine] ( H2L ) was prepared and used as catalyst for oxidation of styrene and α‐methyl styrene with tert‐butylhydroperoxide (TBHP). Oxidation of styrene with TBHP gave benzaldehyde and styrene oxide, but in the case of α‐methylstyrene a mixture of α‐methylstyrene oxide and acetophenone was obtained. The structure of nickel(II) complex ( NiL ) was determined by X‐ray crystallography. Crystal data for NiL at –173 °C: orthorhombic, space group P212121, a = 907.7(1), b = 1289.4(1), c = 1752.4(1) pm, Z = 4, R1 = 0.0454. 相似文献
977.
978.
Mădălina Mihalache Ovidiu Oprea Cornelia Guran Alina M. Holban 《Comptes Rendus Chimie》2018,21(1):32-40
The four divalent nickel complexes having α-ketoglutaric acid (H2A) and 1-(o-tolyl)biguanide (TB) ligands have been synthesized, characterized, and tested for antibacterial and antitumor activity.The proposed formulas for these complexes are [Ni(TB)(HA)(H2O)2]Cl (C1), [Ni(TB)(HA)(H2O)2]Br (C2), [Ni(TB)(HA)]NO3·H2O (C3), and [Ni(TB)(HA)]CH3COO (C4), where HA represents deprotonated H2A.For the four complexes and for the ligands used in the synthesis, the antibacterial activity against Staphylococcus aureus ATCC 25923 and Pseudomonas aeruginosa ATCC 27853 and antitumor activity in HeLa tumor cells were tested. A moderate cytotoxic effect of C3 and C4 complexes has been observed on the development and metabolic activity of HeLa cells, whereas C1 and C2 ligands have a very low effect on them.The synthesized complexes (obtained) inhibit adherence to the inert substrate of bacterial strains S. aureus and P. aeruginosa; therefore, they may be candidates for (potential) therapeutic applications. 相似文献
979.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(28):8328-8332
Enantioselective nickel‐catalyzed arylative cyclizations of substrates containing a Z ‐allylic phosphate tethered to an alkyne are described. These reactions give multisubstituted chiral aza‐ and carbocycles, and are initiated by the addition of an arylboronic acid to the alkyne, followed by cyclization of the resulting alkenylnickel species onto the allylic phosphate. The reversible E /Z isomerization of the alkenylnickel species is essential for the success of the reactions. 相似文献
980.
Jing Kong Wei Liu Fenglong Wang Xinzhen Wang Liqiang Luan Jiurong Liu Yuan Wang Zijun Zhang Masahiro Itoh Ken-ichi Machida 《Journal of solid state chemistry》2011,184(11):2994-3001
Monodispersed Ni flower-like architectures with size of 1–2 μm were synthesized through a facile solvent-thermal process in 1,2-propanediol solution in the presence of polyethylene glycol (PEG) and sodium alkali for electromagnetic absorption application. The Ni architectures are composed of nanoflakes, which assemble to form three dimensional flower-like structure, and the thickness of nanoflakes is about 10–40 nm. A possible formation mechanism for Ni flower-like architectures was proposed and it was confirmed by the control experiments. The Ni architectures exhibited a saturation magnetization (Ms) of 47.7 emu/g and a large coercivity (Hcj) of 332.3 Oe. The epoxy resin composites with 20 vol% Ni sample provided good electromagnetic wave absorption performance (reflection loss <−20 dB) in the range of 2.8–6.3 GHz over absorber thickness of 2.6–5.0 mm. 相似文献