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91.
92.
Kiyoshi Hasebe Satoshi Hikima Hitoshi Yoshida 《Fresenius' Journal of Analytical Chemistry》1990,336(7):586-588
Summary An electrochemical method for the determination of l-lactic acid using the specific reaction of lactate oxidase, has been studied and applied to lactic acid beverage and yoghurt. The technique is reasonably rapid and simple to perform. The calibration curve is linear in the concentration range from 1.0 to 20 mol/l, the reproducibility (R.S.D.) at 10 mol/l l-lactic acid is 1.34% (n=6) and the detection limit is 0.29 mol/l (k=2). The method can possibly be used for monitoring l-lactate or l-lactic acid in food industries and clinical laboratories. 相似文献
93.
The electronic absorption spectra of four monosubstituted naphthalenes, α-, β-naphthols, and α-, β-naphthylamines have been investigated by means of configuration analysis with particular attention to the dependence of spectra on the position of substitution and on the electron-donating power of the substituent. The results of molecular orbital calculations based on the Pariser-Parr-Pople method are analyzed in terms of locally excited states and intramolecular charge-transfer configurations. The characteristic changes in location and polarization of the Lb, La, and Bb bands caused by substitution at the α- or β-position are adequately explained by the analysis. Two strong absorption bands of α-substituted naphthalenes, which appear in place of the Bb band of naphthalene, are shown to result from a mixing of the and states. The amino group exerts a great influence on the electronic structure of the parent molecule, so that the Bb band cannot be identified in the spectrum of β-naphthylamine. 相似文献
94.
Satoshi Ikeda 《International Journal of Theoretical Physics》1974,11(3):205-212
In this paper, a non-local field (i.e. the (x, ψ)-field) is constructed by regarding the spinor (ψ) as the internal freedom attached to each point (x). Since this field is likened to a unified field between the (x)- and (ψ)-fields, the metric is given bydσψ=gλ dx λψ. Concerning this, some conformally equivalent relations are considered. Next, Weyl's gauge field is introduced into the concept of connection in order to consider the gauge invariance. Finally, some essential features underlying our non-local field are grasped by formulating some fundamental equations of the spin curvature tensors. 相似文献
95.
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97.
The effect of molecular vibrations on electronic transport is investigated with the smallest fullerene C20 bridge, utilizing the Keldysh nonequilibrium Green's function techniques combined with the tight-binding molecular-dynamics method. Large discontinuous steps appear in the differential conductance when the applied bias voltage matches particular vibrational energies. The magnitude of the step is found to vary considerably with the vibrational mode and to depend on the local electronic states besides the strength of electron-vibration coupling. On the basis of this finding, a novel way to control the molecular motion by adjusting the gate voltage is proposed. 相似文献
98.
Phosphoenolpyruvate (PEP) is a phosphorylated glycolytic intermediate that can penetrate the RBC membrane and be metabolized to 2,3-DPG and ATP. In this study, we evaluated the effects of PEP treatment on canine red blood cells (RBCs) cryopreserved with 12.5% (w/v) HES. RBCs were incubated for 30, 60, and 90 min at 37 degrees C with PEP solution containing 60 mM mannitol, 30 mM sodium chloride, 25 mM glucose, 1 mM adenine and 50 mM PEP (340 m osm/kg), pH 6.0 and then cryopreserved in liquid nitrogen with 12.5% (w/v) HES for 2 weeks. 2,3-DPG and saline stabilities of the PEP treated groups were increased and osmotic fragility indices were significantly decreased compared to the untreated control group. There were no differences in 2,3-DPG levels within the PEP treated groups with different PEP incubation times. These results suggest that PEP treatment may be beneficial for the cryopreservation of canine RBCs with HES. 相似文献
99.
By using a sodium atomic vapor we have observed a honeycomb-type multiple-diffraction pattern that was due to a grating induced optically by three noncollinear bichromatic excitation beams. In particular, when the two incident frequencies satisfy the two-photon resonance condition and the atomic density is high, the diffraction is enhanced by electromagnetically induced transparency, and strong Stokes and anti-Stokes components are generated in well-defined directions. 相似文献
100.
Subwavelength optical imaging through a metallic nanorod array 总被引:1,自引:0,他引:1
We propose a subwavelength imaging system without a lens or a mirror but with an array of metallic nanorods. The near-field components of dipole sources were plasmonically transferred through the rod array to reproduce the source distribution in the other side. We calculated the field distribution at the different planes of imaging process using the finite-difference time-domain algorithm and found that the spatial resolution was 40 nm given by the rod size and spacing. A typical configuration is a hexagonal arrangement of silver rods of 50 nm height and 20 nm diameter. We also show that the image formation highly depends on the coherence and the polarization of the source distribution and the source-array distance. 相似文献