Typical symptoms of pink root rot were observed in Chinese onions in Quang Nam and Nghe An provinces in Vietnam in 2007. The pathogen recognised as the cause of pink root rot in onions, Phoma ...terrestris , was isolated from diseased roots. This is the first report of pink root rot and P. terrestris in Vietnam.
Resistant cucurbit rootstocks provided an effective control measure for Fusarium wilt of watermelon caused by
Fusarium oxysporum
f. sp.
niveum
in Nghe An province, Vietnam. The hybrid cultivar, ...Bulrojangsaeng (
Lagenaria siceraria
) was the most suitable rootstock on all criteria but the seed is expensive. Therefore, the local Bau trang cultivar (
L. siceraria
) was adopted by farmers as the preferred rootstock on the basis of the low-cost seed. The grafting process is described and illustrated.
The Mn5Ge3 compound, thanks to its room-temperature ferromagnetism, metallic character and ability to epitaxially grow on germanium, has emerged as a potential candidate for spin injection into ...group-IV semiconductors. We investigate the effect of carbon doping in epitaxial Mn5Ge3 films and show that incorporation of carbon into interstitial sites of Mn5Ge3 can allow not only to enhance the magnetic properties but also increase the thermal stability of Mn5Ge3 up to a temperature as high as 850 °C. These results open perspectives to realize spintronic devices based on Mn5Ge3Cx/Ge heterostructures that are compatible with the Si-based complementary metal-oxide-semiconductor (CMOS) technology.
Typical symptoms of pink root rot were observed in Chinese onions in Quang Nam and Nghe An provinces in Vietnam in 2007. The pathogen recognised as the cause of pink root rot in onions,
Phoma ...terrestris
, was isolated from diseased roots. This is the first report of pink root rot and
P. terrestris
in Vietnam.
Three tetrapeptides incorporating a 14-membered (R i +1, S i +2) cycloisodityrosine at the i + 1 and i + 2 positions were designed and synthesized. Conformational analysis by 1H NMR and CD spectra as ...well as molecular modeling indicated that they all adopt a β-turn conformation. While the CD spectrum of compound 2 is characteristic of the typical type-II β-turn (maximum at ∼200 nm and a minimum at ∼220 nm), that of 1a (atropisomer of 2) is opposite in sign to the expected spectrum of the type-II β-turn.
We report on the Mn segregation and diffusion during the epitaxial overgrowth of Ge on Mn
5Ge
3/Ge(111) heterostructures. It is shown that the underneath Mn
5Ge
3 layers remain stabilized at the ...interface with the substrate while a small amount of Mn can leave the layers and floats at the Ge growth front. Mn can then act as a surfactant during Ge growth along the (111) orientation. The Mn segregation length and also the state of Mn atoms incorporated in the Ge layers are found to depend on the growth temperature. At a growth temperature of 250
°C, a segregation length of ~
10
nm is observed and Mn atoms incorporated in the Ge layers are uniformly distributed. At 450
°C, segregated Mn atoms can react with Ge to form Mn
5Ge
3 clusters inside the Ge overgrown layer. Such Mn
5Ge
3 clusters display random orientations and induce modification of the magnetic anisotropy of the whole film.
We report on the structural and magnetic properties of epitaxial Mn
5Ge
3 films grown by molecular beam epitaxy (MBE) on Ge(111) substrates with film thicknesses ranging from 5 to ~
185
nm. It is ...shown that
epitaxial Mn
5Ge
3 films with a thickness as large as 185
nm can be obtained despite a misfit of ~
3.7% between two materials. Measurements of the in-plane lattice parameter carried out by means of reflection high-energy electron diffraction (RHEED) revealed that Mn
5Ge
3 films were fully relieved of strain after deposition of the first monolayer. For film thicknesses smaller than 50
nm, the easy axis of magnetization is found to lie in the hexagonal basal (001) plan, parallel to the interface and the hard axis is perpendicular to the layers. When the film thickness increases above 50
nm, magnetization measurements with magnetic field applied in-plane of the samples reveal that the easy axis of magnetization progressively turns out of the hexagonal basal (001) plan of Mn
5Ge
3. Even for Mn
5Ge
3 films with a thickness larger than 185
nm, the easy axis of magnetization never becomes perpendicular to the sample surface as being expected for bulk Mn
5Ge
3 materials.
Spin-charge interconversion (SCI) phenomena have attracted a growing interest in the field of spintronics as means to detect spin currents or manipulate the magnetization of ferromagnets. The key ...ingredients to exploit these assets are a large conversion efficiency, the scalability down to the nanometer scale and the integrability with opto-electronic and spintronic devices. Here we show that, when an ultrathin Bi film is epitaxially grown on top of a Ge(111) substrate, quantum size effects arising in nanometric Bi islands drastically boost the SCI efficiency, even at room temperature. Using x-ray diffraction (XRD), scanning tunneling microscopy (STM) and spin- and angle-resolved photoemission (S-ARPES) we obtain a clear picture of the film morphology, crystallography and electronic structure. We then exploit the Rashba-Edelstein effect (REE) and inverse Rashba-Edelstein effect (IREE) to directly quantify the SCI efficiency using optical and electrical spin injection.
Molecular beam epitaxy technique has been used to deposit a single layer and a bilayer of MoSe 2 on sapphire. Extensive characterizations including in-situ and ex-situ measurements show that the ...layered MoSe 2 grows in a scalable manner on the substrate and reveals characteristics of a stoichiometric 2H-phase. The layered MoSe 2 exhibits polycrystalline features with domains separated by defects and boundaries. Temperature and magnetic field dependent resistivity measurements unveil a carrier hopping character described within two-dimensional variable range hopping mechanism. Moreover, a negative magnetoresistance was observed, stressing a fascinating feature of the charge transport under the application of a magnetic field in the layered MoSe 2 system. This negative magnetoresistance observed at millimeter-scale is similar to that observed recently at room temperature inWS2 flakes at a micrometer scale Zhang et al., Appl. Phys. Lett. 108, 153114 (2016). This scalability highlights the fact that the underlying physical mechanism is intrinsic to these two-dimensional materials and occurs at very short scale.
PDF
