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A new synthesis of Mo2(CO)8(-PPh2)2 and W2(CO)8(-PPh2)2 by the reaction of molybdenum and tungsten hexacarbonyls with a tetraazamacrocyclic ligand containing —CH2PPh2 side chains, comprising cleavage of the phosphorus-methylene bond has been performed. The complexes have been investigated by magnetic and spectroscopic measurements and by single-crystal structure analyses. The structural characterization of a new polymorph of Mo2(CO)8(-PPh2)2 has been described.  相似文献   
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The synthesis, as well as chemical and structural characterization, of 1-(p-toluenesulfonyl)cytosine (1) and its dinuclear complexes of the composition Pd2(1-TosC?N3,N4)4 (3) and Pd2(1-TosC?N3,N4)2DMSO2Cl2 (4) by means of ESI-MS, IR, 1H NMR and X-ray single crystal analysis are described. Ligand 1 exists in the preferred aminooxo tautomeric form, while both dinuclear complexes reveal the presence of the iminooxo form of the ligand, where 1-TosC? stands for the anion of the cytosine derivative of 1, bridging two palladium atoms. Complex 3 has a paddlewheel structure with two square-planar coordination spheres, consisting of four N atoms each, mutually parallel and perpendicular to the interpalladium vector. Complex 4 is characterized by two mutually parallel square-planar coordination spheres consisting of two nitrogens, sulfur from the solvent molecule and a chloride. A feasible chemical route for the formation of 3 and 4 via the kinetically favoured mononuclear complex Pd(1-TosC–N3)2Cl2 (2) is proposed, based on the IR, 1H NMR, mass spectrometry, elemental analysis and X-ray structure analysis data.  相似文献   
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We establish the connection between the standard intertwining operators for a square integrable representation and its Aubert involution. In the cases of special orthogonal groups and symplectic groups, we define the R-group for a nontempered unitary representation, under the assumption that the Aubert involution of the representation is square-integrable.  相似文献   
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A 1,3-dihexadecyl-1H-benzo[d]imidazol-3-ium-tetraphenylborate (DHBI-TPB) ion-pair implemented in DHBI-TPB surfactant sensor was used for the potentiometric quantification of anionic surfactants in detergents and commercial household care products. The DHBI-TPB ion-pair was characterized by FTIR spectroscopy and computational analysis which revealed a crucial contribution of the C–H∙∙∙π contacts for the optimal complex formation. The DHBI-TPB sensor potentiometric response showed excellent analytical properties and Nernstian slope for SDS (60.1 mV/decade) with LOD 3.2 × 10−7 M; and DBS (58.4 mV/decade) with LOD 6.1 × 10−7 M was obtained. The sensor possesses exceptional resistance to different organic and inorganic interferences in broad pH (2–10) range. DMIC used as a titrant demonstrated superior analytical performances for potentiometric titrations of SDS, compared to other tested cationic surfactants (DMIC > CTAB > CPC > Hyamine 1622). The combination of DHBI-TPB sensor and DMIC was successfully employed to perform titrations of the highly soluble alkane sulfonate homologues. Nonionic surfactants (increased concentration and number of EO groups) had a negative impact on anionic surfactant titration curves and a signal change. The DHBI-TPB sensor was effectively employed for the determination of technical grade anionic surfactants presenting the recoveries from 99.5 to 101.3%. The sensor was applied on twelve powered samples as well as liquid-gel and handwashing home care detergents containing anionic surfactants. The obtained results showed good agreement compared to the outcomes measured by ISE surfactant sensor and a two-phase titration method. The developed DHBI-TPB surfactant sensor could be used for quality control in industry and has great potential in environmental monitoring.  相似文献   
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Less is more: an open-framework zirconium phosphate with unusual 7-ring channels was synthesized ionothermally from a deep-eutectic solvent. This small-pore material displays a CO(2)/CH(4) adsorption ratio (17.3 at 1 bar) that is significantly higher than that of typical 8-ring materials, making it highly attractive for CO(2)/CH(4) separations.  相似文献   
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In the crystal structure of the title compound, [Zn(C18H14NO2)2]·C2H6O, the Zn atom displays a highly distorted octa­hedral coordination involving the O and N atoms of two mol­ecules of the Schiff base 1‐[N‐(2‐methoxy­phenyl)imino­methyl]naphthalen‐2(1H)‐one, which acts as an O,N,O′‐tridentate ligand. The ethanol mol­ecule is bound to the methoxy group of one ligand mol­ecule via a hydrogen bond.  相似文献   
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The title compound, C8H8N3S+·Cl·2H2O, has been synthesized and characterized both spectroscopically and structurally. The structure consists of 1,3‐benzothia­zole‐6‐carboxamidinium cations, chloride anions and water mol­ecules, all interconnected by hydrogen bonds into a three‐dimensional network. The 1,3‐benzo­thia­zole moiety is inclined to the 6‐­amidine group by 36.71 (9)°.  相似文献   
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