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81.
Two new coordination polymers of PbII complexes with bridging 4,4′‐[(1E)‐ethane‐1,2‐diyl]bis[pyridine] (ebp), thiocyanato, and acetato ligands, [Pb(μ‐SCN)2(μ‐ebp)1.5]n ( 1 ) and {[Pb(μ‐OAc)(μ‐ebp)](ClO4)}n ( 2 ), were synthesized and characterized by elemental analysis, FT‐IR, 1H‐ and 13C‐NMR, thermal analysis, and single‐crystal X‐ray diffraction. In 1 , the Pb2+ ions are doubly bridged by both the ebp and the SCN− ligands into a two‐dimensional polymeric network. The seven‐coordinate geometry around the Pb2+ ion in 1 is a distorted monocapped trigonal prism, in which the Pb2+ ions have a less‐common holodirected geometry. In 2 , the Pb2+ ions are bridged by AcO− ligands forming linear chains, which are also further bridged by the neutral ebp ligands into a two‐dimensional polymeric framework. The Pb2+ ions have a five‐coordinate geometry with two N‐atoms from two ebp ligands and three O‐atoms of AcO−. Although ClO acts as a counter‐ion, it also makes weak interactions with the Pb2+ center. The arrangement of the ligands in 2 exhibits hemidirected geometry, and the coordination gap around the Pb2+ ion is possibly occupied by a configurationally active lone pair of electrons. 相似文献
82.
Summary Mono, bis and tris complexes of rhodium(III) with phenyl-2-picolylketone-2-pyridyl hydrazone (PPKPyH) have been characterized. In every case, the imino-proton of PPKPyH shows marked acidity associated with the coordination to rhodium(III). Electronic spectra show that all complexes are octahedral. The B-values suggest a strong covalency in the metal-ligand -bond and the Dq-values indicate a medium-strong ligand field. The magnetic susceptibility indicates that PPKPyH forms low-spin complexes with rhodium(III).1H n.m.r. spectra show that the tris(ligand) complexes arecis isomers. I.r. spectra show that the ligand is neutral or monobasic tridentate or bidentate. Far i.r. studies show that [Rh(PPKPyH)X3] · 2 H2O (X = Cl, Br or I) aremer isomers. The effect of pH variation on the rection products is also discussed. 相似文献
83.
A sensitive cathodic stripping voltammetric method is developed for determination of lead(II), with adsorptive collection of complexes with Pyrogallol red (PGR) on to a hanging mercury drop electrode. After accumulation of the complex at −0.80 V vs. Ag/AgCl reference electrode, the potential is scanned in a negative direction from −0.20 to −0.50 V with differential pulse method. Then the reduction peak current for the lead(II)-PGR complex is measured at −0.39 V. The influence of reagent and instrumental variables was completely studied by factorial design analysis. The optimum analytical conditions for the determination of lead(II) were established. Under optimum conditions, lead(II) determined in the range of 0.1-30.0 ng ml−1 with a limit of detection of 0.06 ng ml−1. The method is successfully applied to determination of lead(II) in water sample. 相似文献
84.
Mir Ali Farajzadeh Mortaza Ebrahimi Ali Ranji Elham Feyz Vali Bejani Amir Abbas Matin 《Mikrochimica acta》2006,153(1-2):73-78
High performance liquid chromatography (HPLC) and gas chromatography (GC) are introduced for analysis of polymer lubricants
(stearamide, oleamide and erucamide). In the HPLC method, a reverse phase octadecylsilane (ODS) column along with acetonitrile/methanol
(60:40) as a mobile phase were used. Detection of analytes was performed by a UV detector at 202 nm. The analysis time was
less than 8 min. In the GC method, polar capillary column and flame ionization detector (FID) were used for separations and
detection, respectively. The analysis time by GC was longer than HPLC and was about 30 min. Limits of detection, linear range
and repeatability of both methods are similar, but determination of oleamide in real samples by HPLC method is difficult due
to complexity of the initial part of HPLC chromatogram in polyethylene samples. That problem is not observed in the GC method.
Detection limits in both methods for all analytes are lower than 0.003% which are much lower than the amount of lubricants
in commercial polymers (0.05–0.2%). 相似文献
85.
Acta Mathematica Sinica, English Series - In this research article, we shall give some reverse Arithmetic-Geometric mean inequalities for unital positive linear maps on Hilbert space operators... 相似文献
86.
Summary
Bis(cyclopentadienyl)titanium(IV) diisothiocyanate [(Cp)2-Ti(NCS)2] reacts with MCl2 (M = Cu, Pd or Pt), [CuCl(PPh3)3], [RuCl2(PPh3)3] and [RuCl2(DMSO)4] (DMSO = dimethylsulphoxide) giving solid compounds of stochiometry [(Cp)2Ti(-NCS)2MCl2] (M = Cu, Pd or Pt), [(Cp)2Ti(-NCS)2CuCl(PPh3)], [(Cp)2Ti(-NCS)2-RuCl(PPh3)2]Cl and [(Cp)2Ti(-NCS)2RuCl2(DMSO)2]. These products have been characterized by physicochemical and spectroscopic methods. 相似文献
87.
88.
89.
Joshua M. Little Jiayue Sun Ali Kamali Amy Chen Asher C. Leff Yang Li Leah K. Borden Thilini U. Dissanayake Deborah Essumang Benita O. Oseleononmen Dongxia Liu Taylor J. Woehl Po-Yen Chen 《Advanced functional materials》2023,33(30):2215222
Assembling 2D-material (2DM) nanosheets into micro- and macro-architectures with augmented functionalities requires effective strategies to overcome nanosheet restacking. Conventional assembly approaches involve external binders and/or functionalization, which inevitably sacrifice 2DM's nanoscale properties. Noble metal ions (NMI) are promising ionic crosslinkers, which can simultaneously assemble 2DM nanosheets and induce synergistic properties. Herein, a collection of NMI–2DM complexes are screened and categorized into two sub-groups. Based on the zeta potentials, two assembly approaches are developed to obtain 1) NMI-crosslinked 2DM hydrogels/aerogels for heterostructured catalysts and 2) NMI–2DM inks for templated synthesis. First, tetraammineplatinum(II) nitrate (TPtN) serves as an efficient ionic crosslinker to agglomerate various 2DM dispersions. By utilizing micro-textured assembly platforms, various TPtN–2DM hydrogels are fabricated in a scalable fashion. Afterward, these hydrogels are lyophilized and thermally reduced to synthesize Pt-decorated 2DM aerogels (Pt@2DM). The Pt@2DM heterostructures demonstrate high, substrate-dependent catalytic activities and promote different reaction pathways in the hydrogenation of 3-nitrostyrene. Second, PtCl4 can be incorporated into 2DM dispersions at high NMI molarities to prepare a series of PtCl4–2DM inks with high colloidal stability. By adopting the PtCl4–graphene oxide ink, various Pt micro-structures with replicated topographies are synthesized with accurate control of grain sizes and porosities. 相似文献
90.
El-Moursy Ali A. Sibai Fadi N. Rehman Jahanzeb Gouda Omar M. Gaber Abdelrahman T. Khedr Ahmed M. 《Wireless Personal Communications》2022,124(2):1525-1555
Wireless Personal Communications - The development of Smart Home Controllers has seen rapid growth in recent years, especially for smart devices, that can utilize the Internet of Things (IoT).... 相似文献