排序方式: 共有9条查询结果,搜索用时 31 毫秒
1
1.
Bode M Heide M von Bergmann K Ferriani P Heinze S Bihlmayer G Kubetzka A Pietzsch O Blügel S Wiesendanger R 《Nature》2007,447(7141):190-193
Chirality is a fascinating phenomenon that can manifest itself in subtle ways, for example in biochemistry (in the observed single-handedness of biomolecules) and in particle physics (in the charge-parity violation of electroweak interactions). In condensed matter, magnetic materials can also display single-handed, or homochiral, spin structures. This may be caused by the Dzyaloshinskii-Moriya interaction, which arises from spin-orbit scattering of electrons in an inversion-asymmetric crystal field. This effect is typically irrelevant in bulk metals as their crystals are inversion symmetric. However, low-dimensional systems lack structural inversion symmetry, so that homochiral spin structures may occur. Here we report the observation of magnetic order of a specific chirality in a single atomic layer of manganese on a tungsten (110) substrate. Spin-polarized scanning tunnelling microscopy reveals that adjacent spins are not perfectly antiferromagnetic but slightly canted, resulting in a spin spiral structure with a period of about 12 nm. We show by quantitative theory that this chiral order is caused by the Dzyaloshinskii-Moriya interaction and leads to a left-rotating spin cycloid. Our findings confirm the significance of this interaction for magnets in reduced dimensions. Chirality in nanoscale magnets may play a crucial role in spintronic devices, where the spin rather than the charge of an electron is used for data transmission and manipulation. For instance, a spin-polarized current flowing through chiral magnetic structures will exert a spin-torque on the magnetic structure, causing a variety of excitations or manipulations of the magnetization and giving rise to microwave emission, magnetization switching, or magnetic motors. 相似文献
2.
3.
J E Corrie B D Brandmeier R E Ferguson D R Trentham J Kendrick-Jones S C Hopkins U A van der Heide Y E Goldman C Sabido-David R E Dale S Criddle M Irving 《Nature》1999,400(6743):425-430
A new method is described for measuring motions of protein domains in their native environment on the physiological timescale. Pairs of cysteines are introduced into the domain at sites chosen from its static structure and are crosslinked by a bifunctional rhodamine. Domain orientation in a reconstituted macromolecular complex is determined by combining fluorescence polarization data from a small number of such labelled cysteine pairs. This approach bridges the gap between in vitro studies of protein structure and cellular studies of protein function and is used here to measure the tilt and twist of the myosin light-chain domain with respect to actin filaments in single muscle cells. The results reveal the structural basis for the lever-arm action of the light-chain domain of the myosin motor during force generation in muscle. 相似文献
4.
E. A. Heide 《Cellular and molecular life sciences : CMLS》1966,22(10):703-704
Summary Report on a method to produce, without refrigeration and solvents, a tobacco smoke condensate of the tobacco main-stream smoke of the particulate phase. Identification obtained by the electron fine beam diffraction of crystals in the sediment of the smoke condensate of cigarettes and cigars.
Wissenschaftlicher Gast am Institut für Elektronenmikroskopie des Fritz-Haber-Instituts der Max-Planck-Gesellschaft. 相似文献
Wissenschaftlicher Gast am Institut für Elektronenmikroskopie des Fritz-Haber-Instituts der Max-Planck-Gesellschaft. 相似文献
5.
6.
G. W. Oertel P. Knapstein K. Heide 《Cellular and molecular life sciences : CMLS》1969,25(11):1192-1193
Zusammenfassung Nach. i.v. Gabe von 7-3H-Dehydroepiandrosteron wurde menschliches Plasma einer präparativen Zonenelektrophorese unterworfen und in Albumine,
1-,
2-,- und-Globuline zerlegt. Aus den einzelnen Proteinfraktionen trennte man freie Steroide, Steroid-Sulfokonjugate und -Glukuronoside ab und untersuchte letztere Fraktionen auf ihren Gehalt an markierten C19-Steroiden. Es zeigte sich, dass die Steroid-Sulfokonjugate vornehmlich in der Proteinfraktion der Albumine, die Steroid-Glukuronoside dagegen bevorzugt in der Proteinfraktion der
1-Globuline auftraten. 相似文献
7.
Summary The thyroxine binding prealbumin was crystallized by ammonium sulphate, sodium sulphate, magnesium sulphate, sodium phosphate and potassium phosphate. The form of the orthorhombic crystals was dependent on pH.
Für Diskussionen über die Form der Kristalle sind wir Herrn Prof. Dr. E.Hellner und Herrn Dr. R.Allmann vom Mineralogischen Institut der Universität Marburg zu Dank verpflichtet. 相似文献
Für Diskussionen über die Form der Kristalle sind wir Herrn Prof. Dr. E.Hellner und Herrn Dr. R.Allmann vom Mineralogischen Institut der Universität Marburg zu Dank verpflichtet. 相似文献
8.
9.
The ABBA family of aromatic prenyltransferases: broadening natural product diversity 总被引:1,自引:0,他引:1
Tello M Kuzuyama T Heide L Noel JP Richard SB 《Cellular and molecular life sciences : CMLS》2008,65(10):1459-1463
1