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21.
We carried out an experimental and numerical investigation of photoinduced voltage at normal incidence in the nondiffraction regime, which was not predicted to occur by the simple momentum conservation model. We prepared two samples: one having space inversion symmetry and the other without this feature. At normal incidence in the nondiffraction regime, we observed a finite signal only for the asymmetric structure. We found that surface plasmon polaritons (SPPs) are excited by the signal and are attributed to the origin of the voltage. We also evaluated the radiation force of light by using the Maxwell stress tensor and found that pressure of light and not shear force is mainly induced in the structure due to the asymmetric excitation of SPPs. 相似文献
22.
23.
N. Nakayama K. Kosuge S. Kachi T. Shinjo T. Takada 《Journal of solid state chemistry》1980,33(3):351-356
Magnetic susceptibilities of Ba2FeS3, Ba2CoS3, and Ba2MnS3 show rounded maxima at 130, 125, and 100 K, respectively, which are due to quasi-one-dimensional antiferromagnetic short-range ordering. Intrachain interactions, , are estimated to be ?20, ?15, and ?12 K, respectively. 57Fe Mössbauer spectra of Ba2FeS3 and 57Fe-doped Ba2CoS3 and Ba2MnS3 at 4.2 K show long-range antiferromagnetic ordering, due to the interchain interaction. The profile of Mössbauer spectra at 4.2 K is analyzed based on the coexistence of magnetic hyperfine and quadrupole interactions, and magnetic hyperfine fields at 4.2 K are estimated to be 36, 29, and 59 kOe, respectively. 相似文献
24.
25.
26.
The spin dynamics of 2-dimensional ferromagnetic monolayers of [MnSb/Sb] were studied by the
+SR method using pulsed sub-surface muons with a momentum of 18 – 25 MeV/c. A gradual growth of a static field along the
+ spin below 200 K and a divergent increase of the relaxation rate at around 25 K were observed in the 1 monolayer sample, related to the critical fluctuations in this magnetic superlattice. 相似文献
27.
Semiempirical values of the Slater parameters F
2(2p,2p) and G
1(2s, 2p) have been determined for the atoms and ions with the electron configurations 1s
22s
m2p
n from the experimental atomic energy levels. Particular attention has been paid to get the values of the parameters to be used for semiempirical calculations on molecular electronic structure. The calculation has also yielded E
av's, the average energies of configurations of these atoms. Evaluation of the semiempirical or effective value of F
0 from E of an appropriate electron-transfer reaction, based on the idea presented by Anno [15], is also referred to in the present paper. The semiempirical values of the Slater parameters as well as those of E's and E
av's show almost linear dependence upon atomic number Z through isoelectronic series. From the overall tendency of the correlation lines, it is pointed out that the assignment of atomic energy levels of Na5+ (1s
22p
4) must be wrong.
Zusammenfassung Semiempirische Werte der Slater-Parameter F 2(2p,2p) und G 1(2s, 2p) wurden für die Atome und Ionen mit der Elektronenkonfiguration 1s 22s m2p n aus den experimentellen atomaren Energietermen bestimmt. Insbesondere wurden die Parameter bestimmt, die für semiempirische Berechnungen der Elektronenstruktur von Molekülen benötigt werden. Die Berechnung ergibt weiterhin Werte von E av, der Durchschnittsenergie der Konfigurationen der genannten Atome. Die vorliegende Arbeit geht auch auf die Bestimmung des semiempirischen bzw. effektiven Wertes von F 0 aus E einer geeigneten Elektronenübertragungsreaktion ein, die auf die Arbeit von Anno [15] zurückgeht. Die semiempirischen Werte der Slater-Parameter sowie der E und E av zeigen annähernd lineare Abhängigkeit von der Atomnummer Z innerhalb isoelektronischer Reihen. Aus dem Gesamtverhalten der genannten Kurven wird geschlossen, da die Zuordnung der atomaren Energieterme von Na5+(1s 22p 4) falsch sein dürfte.
Résumé Détermination à partir des niveaux d'énergie atomiques expérimentaux des valeurs semi-empiriques des paramètres de Slater F 2(2p, 2p) et G 1(2s, 2p) pour les atomes et les ions ayant les configurations 1s 22s m2p n. On a fait particulièrement attention d'obtenir les valeurs des paramètres à utiliser pour des calculs moléculaires semi-empiriques. Le calcul a aussi fourni les énergies moyennes des configurations de ces atomes. On évoque aussi le calcul de la valeur semi-empirique ou effective de F 0 à partir du E d'une réaction appropriée de transfert électronique, selon une idée de Anno [15]. Les valeurs semiempiriques des paramètres de Slater, ainsi que celles des E et E moy, montrent une dépendance presque linéaire au nombre atomique Z à travers les séries isoélectroniques. A partir des tendances générales des lignes de corrélation, on remarque que l'attribution des niveaux d'énergie atomiques de Na5+(1s 22p 4) doit être fausse.相似文献
28.
57Fe and119Sn Mössbauer spectroscopy as well as X-ray diffractometry were used to study Ti?Ca?Ba?Cu?O high Tc superconductors (Tc=106K) in the 4 to 300 K temperature range. X-ray diffractograms showed the dominant phase of these supercondutors to be 2-1-2-2 type. Three main iron sites were found and associalted with Fe in Cu sites in the real crystal. The dopublet with IS=0.25 mm/s and QS=0.7 mm/s at RT was attributed to the regular Cu site. No magnetic splitting was observed either in Sn or in Fe spectra taken even at 4 and 5K. 相似文献
29.
Hyperfine Interactions - Mössbauer spectroscopy is a useful tool to study the magnetic properties of multilayers from microscopic viewpoints. Recent experimental results relating to the issues... 相似文献
30.
S. Nasu H. Kitagawa M. Yoshida Y. Oda K. Ueda T. Kohara T. Shinjo K. Asayama F. E. Fujita 《Hyperfine Interactions》1990,55(1-4):1355-1362
57Fe Mössbauer measurements have been performed for Fe-doped YBa2 (Cu1-x Fex)3O7-v (x=0.005–0.10) superconducting oxides. Fe atoms mainly substitute at Cul chain sites and the fraction of Fe at Cu2 plane sites is discussed thermodynamically. The spin direction of Fe at Cu2 was determined to be normal to thec-axis using an oxygen deficient specimen having a strong texture along thec-axis. A magnetically broadened spectrum at 4.2 K for Fe at Cul is compared with a simulated one which takes the distribution of hyperfine fields into account. 相似文献