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81.
Brbara L. Almeida Joanna M. Ramos Otvio Versiani Marta Sousa Claudio Alberto Tllez Soto Ana Lúcia Ramalho Mercê Antnio Slvio Mangrich Judith Felcman 《Polyhedron》2008,27(18):3662-3668
A new complex of Cu(II) of stoichiometry [Cu(PCr)(H2O)] was prepared from aqueous solution at pH 6. Its synthesis, characterization, thermogravimetric, vibrational spectroscopy, and electron paramagnetic resonance analyses were described and suggest that phosphocreatine (PCr) in solid state is acting as a tridentate ligand (the nitrogen atom of the guanidine group and the oxygen atoms of the phosphate group and the carboxylate group being the donor atoms). The fourth position is occupied by a water molecule. These results were confirmed through computational calculations (DFT/B3LYP:6-311G theoretical procedure). The tetra coordination of Cu(II) arranged in a quadratic planar geometry was found to be more stable in the DFT calculations. The calculated vibrational spectrum agrees well with the FT-IR experimental spectrum. 相似文献
82.
Yoshito Mitani Judith Velina Lara-Manzano Aaron Rodriguez-Lopez 《Accreditation and quality assurance》2008,13(7):421-426
According to the experience of the successful implementation of proficiency tests (PT) by using the certified reference value
as the assigned value, a new scheme of evaluation is presented by suggesting the use of the uncertainty associated with the
certified value. The technical performance of laboratories is evaluated by the parameter quadratic mean error (QME), which
is the square root of the sum of the square of the bias and that of the standard deviation of the laboratory. This parameter
is considered as the estimate of the measurement uncertainty of the laboratory and is compared to the uncertainty (U) associated with the certified value provided by an NMI. Considering that the calibration and measurement capability, known
as the CMC, is recognized among NMIs, the ratio QME/U enables us to compare the PT relative to the CMC of an NMI, and, consequently, to any other comparison results based on the
CMC of signatories of the mutual recognition arrangement (MRA) of the International Committee of Weights and Measure (CIPM).
Presented at BERM-11, October 2007, Tsukuba, Japan. 相似文献
83.
This paper is concerned with the coordination of inventory control in three-echelon serial and distribution systems under
decentralized control. All installations in these supply chains track echelon inventories. Under decentralized control the
installations will decide upon base stock levels that minimize their own inventory costs. In general these levels do not coincide
with the optimal base stock levels in the global optimum of the chain under centralized control. Hence, the total cost under
decentralized control is larger than under centralized control.
To remove this cost inefficiency, two simple coordination mechanisms are presented: one for serial systems and one for distribution
systems. Both mechanisms are initiated by the most downstream installation(s). The upstream installation increases its base
stock level while the downstream installation compensates the upstream one for the increase of costs and provides it with
a part of its gain from coordination. It is shown that both coordination mechanisms result in the global optimum of the chain
being the unique Nash equilibrium of the corresponding strategic game. Furthermore, all installations agree upon the use of
these mechanisms because they result in lower costs per installation. The practical implementation of these mechanisms is
discussed. 相似文献
84.
Judith R. Goodstein 《Physics in Perspective (PIP)》2001,3(3):271-313
Along with Enrico Fermi, Franco Rasetti played a key role in the rebirth of Italian physics in the 1920s and 1930s. In this
interview he talks about his experiments at Caltech on the Raman effect in 1928–1929, mountain climbing, his passion for bugs,
fossils, and flowers, and doing physics in Florence, Rome, Berlin-Dahlem, and Quebec. Rasetti also reminisces about the Rome
school of mathematics and other scientists he has known and worked with in Europe and in North America, including Robert and
Glenn Millikan, Lise Meitner, and O. M. Corbino. 相似文献
85.
Judith Cudaj 《Tetrahedron letters》2010,51(23):3092-3094
We present a total synthesis of the fungal natural product graphislactone G, a chlorinated resorcylic lactone. The key step is a Suzuki coupling used for the construction of the central biaryl bond. Graphislactone G was prepared in 13 steps with 22% yield starting with orcinol and phloroglucinic acid, where the longest linear sequence consists of nine steps. 相似文献
86.
It is important to understand the molecular mechanisms underlying neuron death following stroke in order to develop effective neuroprotective strategies. Since studies on human stroke are extremely limited due to the difficulty in collecting post-mortem tissue at different time points after the onset of stroke, brain ischaemia research focuses on information derived from in-vitro models of neuronal death through ischaemic injury [1]. This review aims to provide an update on the different in-vitro stroke models with brain microvascular endothelial cells that are currently being used. These models provide a physiologically relevant tool to screen potential neuroprotective drugs in stroke and to study the molecular mechanisms involved in brain ischaemia. 相似文献
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