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91.
We show that two dimensional electrons-holes droplets can exist in superlattice having a structural defect such as a layer with an additional atomic plane. This is a new and cleaner way to produce and study a plasma in two dimensions. 相似文献
92.
A. Dondos und H. Benoit 《Colloid and polymer science》1978,256(2):188
Ohne Zusammenfassung 相似文献
93.
Nuclear orientation experiments on 137mCe impurities in Al2La show directly at almost 0 K that these alloys correspond to the magnetic conditions assumed by Müller-Hartmann and Zittartz. 相似文献
94.
F. Benoit 《Journal of mass spectrometry : JMS》1973,7(12):1407-1413
The heat of formation of the benzoyl cation generated from [C6H5COX]+˙ is found to depend on X, while the heat of formation of the phenyl ion produced therefrom is, with one exception, independent of X. The excess energy of the benzoyl cation can be accounted for by an electronic excited state of the ion in the mass spectra of benzoic acid, benzaldehyde, benzamide, methyl benzoate and possibly benzophenone; the benzoyl cation is not excited in the mass spectra of acetophenone and benzoyl chloride. 相似文献
95.
Trifluoromethylated nitrogen-containing molecules have been shown to have important biological effects and their synthesis is in the focus of the pharmaceutical industry. In the last few years, simple nitrogen derivatives of fluoral, i.e. imines, acetals and oxazolidines, have emerged as powerful building blocks to synthesize these target molecules and relevant precursors. This review summarizes the chemistry of these "N-derivatives of fluoral", with special highlight on the syntheses of peptidomimetic units (amino alcohols, amino acids...) and heterocycles (piperidines, beta-lactams...). 相似文献
96.
Crecelius AC Cornett DS Caprioli RM Williams B Dawant BM Bodenheimer B 《Journal of the American Society for Mass Spectrometry》2005,16(7):1093-1099
We have developed a method to visualize matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI IMS) data aligned with optically determinable tissue structures in three dimensions. Details of the methodology are exemplified using the 3-D reconstruction of myelin basic protein (MBP) in the corpus callosum of a mouse brain. In this procedure, optical images obtained from serial coronal sections are first aligned to each other to reconstruct a surface of the corpus callosum from segmented contours of the aligned images. The MALDI IMS data are then coregistered to the optical images and superimposed into the surface to create the final 3-D visualization. Correlating proteomic data with anatomical structures provides a more comprehensive understanding of healthy and pathological brain functions, and holds promise to be utilized in more complex anatomical arrangements. 相似文献
97.
A. Dondos und H. Benoit 《Colloid and polymer science》1978,256(7):725
Ohne Zusammenfassung 相似文献
98.
Below T2 = 202 K, in the incommensurate phase, a Debye relaxation appears for c33; it can be attributed to a linear coupling between an acoustical mode and a phason. The relaxation time is τ = τ0/(T0?T) with τ0 = 6.2 x 10?12 sec deg and T0 = 200.9 K. The same phenomenon appears more weakly for c11. The c66 elastic constant has a double discontinuity around T1 = 169 K; this shows that in the vicinity of T1 there are two transitions, separated by a temperature interval of 3°. 相似文献
99.
100.
Benoit Kloeckner 《Transformation Groups》2006,11(2):185-194
The group of direct isometries of the hyperbolic space
This isometric action admits many differentiable compactifications into an action on the closed n-dimensional ball. We prove
that all such compactifications are topologically conjugate but not necessarily differentiably conjugate. We give the classifications
of real analytic and smooth compactifications. 相似文献