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81.
Y. Lassailly C. Vettier F. Holtzberg A. Benoit J. Flouquet 《Solid State Communications》1984,52(8):717-719
Neutron diffraction experiments were performed on the divalent thulium compound TmTe. Magnetic structure determination leads to a type II antiferromagnet below the Néel temperature TN = .43 K. No crystal field excitations were observed. 相似文献
82.
A. Dondos und H. Benoit 《Colloid and polymer science》1978,256(2):188
Ohne Zusammenfassung 相似文献
83.
A. Dondos und H. Benoit 《Colloid and polymer science》1978,256(7):725
Ohne Zusammenfassung 相似文献
84.
85.
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
86.
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
87.
Fielicke A von Helden G Meijer G Simard B Rayner DM 《The journal of physical chemistry. B》2005,109(50):23935-23940
We report the vibrational spectra of the carbonyl complexes of anionic gold clusters in the range of the CO stretching frequency as measured in the gas phase using IR multiple photon dissociation spectroscopy. The investigated complexes contain between 3 and 14 Au atoms and up to 7 CO ligands. Special attention is given to the complexes that exhibit saturation CO coverage as well as to the monocarbonyl species. In conjunction with data from the corresponding cationic complexes we quantify how the CO stretching frequency varies with the charge state of the gold cluster. Our results provide a size- and charge-dependent basis to interpret values of the CO stretching frequency measured for CO on deposited gold clusters in terms of the charge states of the clusters. 相似文献
88.
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
89.
All the elastic stiffness constants of thiourea have been measured at room temperature. The value of C66(0.7 × 1010dynes/cm2) is very low. The C11 and C33 constants exhibit discontinuities at 169 and 202 K. The longitudinal acoustic phonons propagating in the c direction are very strongly damped in the vicinity of 202 K. 相似文献
90.
Maxit B Giermanska J Ly I Bendejacq D Mondain-Monval O Ponsinet V 《Langmuir : the ACS journal of surfaces and colloids》2011,27(5):1990-1995
We report on the structures exhibited by two different diblock poly(styrene)-b-poly(acrylic acid) (PS-b-PAA) copolymers in water, a selective solvent. Using a combination of X-ray scattering and freeze fracture-transmission electron microscopy (FF-TEM), we show that these structures can be widely swollen while retaining their initial morphology and a high degree of long-range order. The analysis of the FF-TEM pictures also evidences the presence of water crystallites of regular size and shape within the confined water domains. We relate the growth of these crystallites to the high local ionic strength of the water swelling the PAA brushes. Moreover, the confinement of the crystallites growth shows that the swollen phases have a very robust structure, potentially useful for confining colloidal particles. 相似文献