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71.
The investigations performed in this work have demonstrated that an easy-axis frustrated non-Heisenberg magnet can contain homogeneous phases with the vector (ferromagnetic) and tensor (nematic) orderings, as well as a spatially inhomogeneous phase of the magnetic spiral type. Depending on the relationships between the material parameters, either a ferromagnetic spiral or a spiral of the quadrupole–ferromagnetic type with different periods of the spiral structures can be formed in the system. The phase diagram of the system has been constructed. 相似文献
72.
The aim of this study is the evaluation by mechanical testing of the durability of rigid PVC. The prediction of mechanical durability is made by following the change in the brittle temperature TB at a constant speed by an indentation test after artificial and natural weathering. TB is presented as a possible durability index for thin, extruded rigid PVC profiles. 相似文献
73.
A study by convergent beam electron diffraction has been performed in order to clarify the symmetry of the phase III of Pb2CoWO6. Microdiffractions with higher-order Laue zone on monodomain areas have confirmed the cell proposed in our preceding study. In addition, an ‘axial’ glide plane (c) has been found normal to the b axis. In the conditions of observation, the convergent beam electron diffraction patterns lead to an apparent point group mmm. No breakdown of a mirror symmetry could be found. The discrepancy between this result and the existence of a spontaneous polarisation is discussed. 相似文献
74.
75.
Ph. Savignac E. Elia Aboujaoude N. Collignon M. P. Teulade 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):491-494
Abstract Phosphoryl and silyl chlorides phosphonoalkylation lead to the direct generation of phosphonyl-phosphonyl and phosphonyl-silyl carbanions the properties of which are discussed. 相似文献
76.
V. Ph. Zhuravlev 《Doklady Physics》2017,62(5):271-272
By the example of a brake pad, a typical error is illustrated, i.e., the fact that the initial conditions should be reconsidered upon finding that there is no solution of the static problem in a certain region of parameters (incorrect in the sense of Hadamard). For example, it turns out that the conditions of disk rotation in the positive direction cannot be implemented in the domain of parameters leading to a “paradox.” In this region, the “brake-pad” mechanism is transformed into the “wedge stopper” mechanism. 相似文献
77.
D. Kocheva G. Rainovski J. Jolie N. Pietralla A. Blazhev A. Astier R. Altenkirch S. Ansari Th. Braunroth M. L. Cortés A. Dewald F. Diel M. Djongolov C. Fransen K. Gladnishki A. Hennig V. Karayonchev J. M. Keatings E. Kluge J. Litzinger C. Müller-Gatermann P. Petkov M. Rudigier M. Scheck Ph. Scholz P. Spagnoletti M. Spieker C. Stahl R. Stegmann M. Stoyanova P. Thöle N. Warr V. Werner W. Witt D. Wölk K. O. Zell P. Van Isacker V. Yu. Ponomarev 《The European Physical Journal A - Hadrons and Nuclei》2017,53(9):175
78.
Ph. Vermeulen J. A. Fernández Pierna H. P. van Egmond J. Zegers P. Dardenne V. Baeten 《Analytical and bioanalytical chemistry》2013,405(24):7765-7772
In recent years, near-infrared (NIR) hyperspectral imaging has proved its suitability for quality and safety control in the cereal sector by allowing spectroscopic images to be collected at single-kernel level, which is of great interest to cereal control laboratories. Contaminants in cereals include, inter alia, impurities such as straw, grains from other crops, and insects, as well as undesirable substances such as ergot (sclerotium of Claviceps purpurea). For the cereal sector, the presence of ergot creates a high toxicity risk for animals and humans because of its alkaloid content. A study was undertaken, in which a complete procedure for detecting ergot bodies in cereals was developed, based on their NIR spectral characteristics. These were used to build relevant decision rules based on chemometric tools and on the morphological information obtained from the NIR images. The study sought to transfer this procedure from a pilot online NIR hyperspectral imaging system at laboratory level to a NIR hyperspectral imaging system at industrial level and to validate the latter. All the analyses performed showed that the results obtained using both NIR hyperspectral imaging cameras were quite stable and repeatable. In addition, a correlation higher than 0.94 was obtained between the predicted values obtained by NIR hyperspectral imaging and those supplied by the stereo-microscopic method which is the reference method. The validation of the transferred protocol on blind samples showed that the method could identify and quantify ergot contamination, demonstrating the transferability of the method. These results were obtained on samples with an ergot concentration of 0.02 % which is less than the EC limit for cereals (intervention grains) destined for humans fixed at 0.05 %. Online Abstract Figure
Pictures showing a the manual removal of ergot bodies and b the observation by the stereo-microscopic method (official method); c the metallic holder with the reference material, and d the NIR hyperspectral SisuCHEMA instrument 相似文献
79.
We describe here the synthesis of the enantiomerically pure phosphohomoserine lactone which will serve as an haptenic structure in catalytic antibody preparation. 相似文献
80.
Jahnke T Czasch A Schöffler M Schössler S Käsz M Titze J Kreidi K Grisenti RE Staudte A Jagutzki O Schmidt LP Weber T Schmidt-Böcking H Ueda K Dörner R 《Physical review letters》2007,99(15):153401
We investigate the interatomic Coulombic decay (ICD) of neon dimers following photoionization with simultaneous excitation of the ionized atom (shakeup) in a multiparticle coincidence experiment. We find that, depending on the parity of the excited state, which determines whether ICD takes place via virtual dipole photon emission or overlap of the wave functions, the decay happens at different internuclear distances, illustrating that nuclear dynamics heavily influence the electronic decay in the neon dimer. 相似文献