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101.
On the superconductor YBa2Cu3O7–x between 150 and 300°C, allyl alcohol is isomerized to propionaldehyde (70%) and hydrogenated to 1-propanol (30%) in hydrogen. 相似文献
102.
103.
Balázs Molnár Gyula Simig Tibor Bakó András Dancsó Balázs Volk 《Tetrahedron letters》2012,53(23):2922-2924
A new and efficient synthesis of 5,6-diaminophthalide and a novel thiadiazolophthalide has been accomplished. Both molecules are useful starting compounds for the construction of more complex heterocyclic systems and for the preparation of bioisosteres of methylenedioxyphenyl derivatives. 相似文献
104.
T. Marek Cs. Szeles G. Molnár J. Borossay A. Vértes K. G. Lynn 《Journal of Radioanalytical and Nuclear Chemistry》2000,245(2):329-335
We studied the long-term (190 hours) behaviour of [Zn(propyltetrazole)6](BF4)2 single crystal under high-vacuum (HV) conditions (10–8 torr) with a depth-sensitive technique of positron annihilation spectroscopy (PAS). The obtained data indicate the slow formation of a new near-surface structure which is formed by the decomposition of the [Zn(propyltetrazole)6]2+ ions. The assumption of such a decomposition process was confirmed by additional mass spectroscopic measurements. 相似文献
105.
Peter K. Anastasovski T. E. Bearden C. Ciubotariu W. T. Coffey L. B. Crowell G. J. Evans M. W. Evans R. Flower S. Jeffers A Labounsky B. Lehnert M. Mészáros P. R. Molnár S. Roy J.-P. Vigier 《Foundations of Physics Letters》1999,12(6):579-584
The Michelson interferogram from perfectly reflecting mirrors does not exist in the U(1) gauge theory of electrodynamics, which is therefore seriously flawed. The adoption of an O(3) internal gauge field symmetry allows these flaws to be remedied self-consistently and leads to several developments in electrodynamics, enriching the subject considerably. 相似文献
106.
107.
The binary system LiNbO3-Fe2O3 has been studied by Mössbauer spectroscopy in the concentration range up to 24 mol% Fe2O3. For Fe2O3 concentrations up to 6 mol% iron is incorporated into the matrix of LiNbO3 as Fe2+ and Fe3+, whereby the Fe2+ content decreases with increasing Fe2O3 concentration. Samples containing 9 and 11 mol% Fe2O3 showed only the Fe3+ valence state. There were no indications of any considerable formation of superparamagnetic Fe2O3 clusters up to 11 mol% Fe2O3. This is in agreement with the X-ray and DTA investigations of Takei and Katsumata (1982) who found that a solid solution exists between 0 and 11 mol% Fe2O3. Above 11 mol% the appearance of magnetically split sextets in the Mössbauer spectra indicated the formation of a second α-Fe2O3 phase. The isomer shift, which reflects the electron density at the Fe nucleus, measured as a function of the Fe2O3 concentration showed two steps, one at 6 mol% Fe2O3 (the turning point of the CH axis parameter (Takei et al. 1982) and one at 11 mol% Fe2O3 (phase boundary). These steps were tentatively related to abrupt changes in the spontaneous polarization. 相似文献
108.
Aledealat K Mihajlović G Chen K Field M Sullivan GJ Xiong P Chase PB von Molnár S 《Journal of magnetism and magnetic materials》2010,322(24):L69-L72
We report integration of an InAs quantum well micro-Hall magnetic sensor with microfluidics and real-time detection of moving superparamagnetic beads. Beads moving within and around the Hall cross area result in positive and negative Hall voltage signals, respectively. Relative magnitudes and polarities of the signals measured for a random distribution of immobilized beads over the sensor are in good agreement with calculated values and explain consistently the shape of the dynamic signal. 相似文献
109.
110.
Félix G Abdul-Kader K Mahfoud T Gural'skiy IA Nicolazzi W Salmon L Molnár G Bousseksou A 《Journal of the American Chemical Society》2011,133(39):15342-15345
Nano-objects and thin films displaying molecular spin-crossover phenomena have recently attracted much attention. However, the investigation of spin crossover at reduced sizes is still a big challenge. Here we demonstrate that surface plasmon polariton waves propagating along the interface between a metal and a dielectric layer can be used to detect the spin-state changes in the latter with high sensitivity, even at the nanometer scale. 相似文献