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1.
Europium (Eu+) ions were confined in a Paul trap and detected by non-destructive method. Storage time of Eu+ ions achieved in vacuum was improved by orders of magnitude employing buffer gas cooling. The experimentally detected signal was fitted to the ion response signal and the total number of ions trapped was estimated. It is found that the peak signal amplitude as well as the product of FWHM and the peak signal amplitude is proportional to the total number of trapped ions. The trapped ion secular frequency was swept at different rates and its effect on the absorption line profile was studied both experimentally and theoretically.  相似文献   
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The reactivity of the bidentate ligand 2,3-bis(diphenylphosphino)-N-phenylmaleimide (bppm) with the tetrahedrane cluster PhCCo3(CO)9 under thermolysis and ETC conditions has been studied and found to ultimately give Co3(CO)6221-C(Ph) ${\text{C}}{\text{ = }}{\text{ = }}{\text{C(PPh}}_{\text{2}} {\text{)C(O)NPhC}}$ (O)](μ2-PPh2) as the final product. The intermediate cluster compound PhCCo3(CO)7(bppm), which was observed by IR and 31P NMR spectroscopies, readily and rapidly transforms into the product cluster under the reactions conditions. The solid-state structure of Co3(CO)6221-C(Ph)fptt(O)](μ2-PPh$_{2})$ was unequivocally determined by X-ray crystallography. Co3(CO)62, η2, η1-C(Ph)Õ(O)](μ2-PPh2) crystallizes in the monoclinic space group P2(1)/n, a = 11.825(5) Å, b = 31.20(1) Å, c = 11.831(5) Å, β = 108.720(7)°, V = 4134(7) Å3, Z = 4, d calc = 1.567 Mg/m3; R = 0.0350, R w = 0.0817 for 4747 observed reflections with I > 2σ(I). The X-ray structure confirms the coupling of the benzylidyne ligand with the bppm ligand in Co3(CO)6221-C(Ph)Õ(O)](μ2-PPh2). The course of the thermolysis reaction is identical to those reactions carried out with the related diphosphine ligands bma and bpcd. The utility of electron-transfer catalysis (ETC) in the preparation of PhCCo3(CO)7(bppm) is discussed relative to the reduction potential of the bppm ligand and the tricobalt cluster PhCCo3(CO)9.  相似文献   
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After the publication of the work entitled "Dermatan sulfate in tunicate phylogeny: Order-specific sulfation pattern and the effect of [→4IdoA(2-Sulfate)β-1→3GalNAc(4-Sulfate)β-1→] motifs in dermatan sulfate on heparin cofactor II activity", by Kozlowski et al., BMC Biochemistry 2011, 12:29, we found that the legends to Figures 2 to 5 contain serious mistakes that compromise the comprehension of the work. This correction article contains the correct text of the legends to Figures 2 to 5.  相似文献   
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Russian Journal of General Chemistry - A novel series of bis-isoxazole incorporated benzothiazole derivatives has been designed and synthesized. Molecular structures of the compounds have been...  相似文献   
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The structure of an unexpected compound from the dehydration of an aldol addition product has been determined using 1-D and 2-D NMR techniques. This reaction is the last step in a new synthetic approach to the galanthan ring system. Complete 1H and 13C NMR assignments for two synthetic precursors are also reported.  相似文献   
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Structure and properties of potential nonlinear optical materials   总被引:2,自引:0,他引:2  
The synthesis, structure and properties of four ferrocene derivatives of 2-amino-1,2,3-triazole are reported. Solvatochromism is used as a screening process to assess the potential nonlinear optical behavior of these compounds. In general, this technique involves a number of assumptions, which may not be valid for organometallic complexes. Compound 3 crystallizes in space group P-1 with cell dimensions a = 5.771(2), b = 19.048(5), c = 19.343(5) Å and = 61.104(4), = 88.410(5), = 89.858(5)°; compound 5 crystallizes in space group P21/c with cell dimensions a = 12.545(2), b = 13.308(2), c = 20.513(4) Å and = 104.035(3)°; compound 9 crystallizes in space group P21/n with cell dimensions a = 12.599(4), b = 14.734(4), c = 13.619(5) Å, and = 107.63(2); compound 11 crystallizes in space group P-1 with cell dimensions a = 7.638(3), b = 9.619(4), c = 12.692(5) Å and = 77.588(7), = 78.416(7), = 71.357(7).  相似文献   
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A short H···H intramolecular interaction was reported previously for an anhydride of syn-sesquinorbornene. The synthesis and structure of a such an anhydride with an additional five-membered dithiole ring has been investigated. While hydrogen atom positions are not accurately located, the 1.62 Å separation indicates this molecule is a candidate for the shortest H···H interaction. Two cycloadducts of norbornadiene, which literature suggests might exhibit additional short interactions, are reported also; however, the isomers with minimal intramolecular interactions are the isolated products. C22H20O3S2, 3, crystallizes in P with a = 10.881(4), b = 13.712(8), C = 6.548(8) Å, = 101.32(6), = 107.49(5), = 90.49(4)°, D calc = 1.445 g cm–3, and Z = 2, C21H20O4Cl8, 5, in P21/n with a = 8.168(2), b = 13.488(4), c = 23.500(6) Å, = 94.72(2)°, D calc = 1.597 g cm–3, and Z = 4, C21H28O4, 6, in P> with a = 12.667(2), b = 12.792(2), c = 12.540(2) Å, = 113.51(1), = 98.18(1), = 74.39(1)°, D calc = 1.276 g cm–3, and Z = 4.  相似文献   
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Russian Journal of General Chemistry - A series of novel N-{2-fluoro-6-[(4,6-dimethoxy-1,3,5-triazin-2-yl)methyl]phenyl} carboxamide derivatives has been synthesized, and their molecular structures...  相似文献   
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