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The growth of two-dimensional van der Waals magnetic materials presents attractive opportunities for exploring new physical phenomena and valuable applications. Among these materials, Fe3GeTe2 (FGT) exhibits a variety of remarkable properties and has garnered significant attention. Herein, we have for the first time created a nanomesh structure—a honeycomb-like array of hexagonal nanopores—with the zigzag pore-edge atomic structure on thin FGT flakes with and without oxidation of the pore edges. It is revealed that the magnitude of ferromagnetism (FM) significantly increases in both samples compared with bulk flakes without nanomeshes. Critical temperature annealing results in the formation of zigzag pore edges and interpore zigzag-edge nanoribbons. We unveil that the non-oxide (O) termination of the Fe dangling bonds on these zigzag edges enhances FM behavior, while O-termination suppresses this FM by introducing antiferromagnetic behavior through edge O–Fe coupling. FGT nanomeshes hold promise for the creation of strong FM and their effective application in magnetic and spintronic systems. [ABSTRACT FROM AUTHOR]

This paper reports on the design, implementation and assessment of a new approach course structure based on the combination of three cooperative methodologies. The main goal is to reduce the percentage of non-passed students focusing the learning process on students by offering different alternatives and motivational activities based on working in small groups on a robotic project and changing the course assessment. The microprocessor course is a subject in the undergraduate program of telecommunication engineering at the University of the Balearic Islands (UIB) in Spain. Its traditional teaching methodology was based on Lecture sessions, Problem sessions and Practical activities in the lab (L/P/P). This methodology was changed to comply with the Bologna requirements, where new skills must be addressed and learned during the educational process. Self-Directed Learning activities (SDLA) for lecture sessions and Project based learning (PjBL) for Laboratory sessions were implemented in combination with a final competition activity between groups (CnBL). This paper describes the design, implementation and results; showing the benefits of these new teaching methods, improving student's motivation including a robotic buggy project and allowing new learning strategies based on a practical point of view and adaptability to students' previous skills. (Contains 4 tables and 5 figures.)

Abstract: Leaf (brown) and stripe (yellow) rusts, caused by Puccinia triticina and Puccinia striiformis, respectively, are fungal diseases of wheat (Triticum aestivum) that cause significant yield losses annually in many [...]

The magnetoresistance (MR) in Fe/Cr magnetic multilayers (MML) has been measured under high pressure up to 2.5 GPa. It is found that the spin-dependent scattering plays an important role in the pressure dependence of MR ratio. In the present work, for [[Fe(20 [Angstrom])/Cr(10 [Angstrom])].sub.20] MML with antiferromagnetic (AF) state, the pressure coefficient of saturation field [H.sub.s] is (1/[H.sub.s])([partial derivative][H.sub.s]/P[partial derivative]) = 3.3 x [10.sup.-2] [GPa.sup.-1] between 0.1 and 2.5 GPa. We found that the (1/|J|)([partial derivative]|J|/[partial derivative]P) for AF-Fe/Cr MML with polycrystalline structure is opposite in sign to that with epitaxial one. For [Fe(20 [[Angstrom])/Cr(22 [Angstrom])].sub.20] MML with ferromagnetic (F) state, anisotropic magnetoresistance (AMR) decreases with increasing pressure. It is suggested that the anisotropy constant decreases with weakening spin-orbit interaction at high pressure. At high field, the AMR is easily suppressed by applying pressure while the giant magnetoresistance around [H.sub.s] increases slightly with increasing pressure for polycrystalline Fe/Cr MML. Index Terms--Giant magnetoresistance, multilayers, pressure effects, superlattices, thin films.

A new study uses electron microscopy and spectroscopy techniques to investigate the chemical and structural characteristics of FexMn1-x alloys in FexMn1-x/Ir superlattices.

Eleocharis atropurpurea is an annual weed and distributed widely in pantropical and subtropical regions. Yet, there have been no studies on the allelopathy of E. atropurpurea. Therefore, we investigated the allelopathic potential of E. atropurpurea to identify allelopathic substances from it. The aqueous methanolic extracts of E. atropurpurea showed an inhibitory effect on the seedling growth of lettuce, rapeseed, barnyard grass and foxtail fescue. Inhibition was species- and concentration-dependent. Two substances, syringaldehyde and acetosyringone, were isolated by using chromatography and using spectroscopy their structures were determined. Syringaldehyde and acetosyringone inhibited the shoot and root growth of cress and barnyard grass at concentrations greater than 3.0 mM except shoot growth of barnyard grass by acetosyringone. Concentration and seedling growth of cress and barnyard grass displayed a negative correlation. The I50 values of syringaldehyde and acetosyringone for the shoot and root growth of cress were 1.67 and 1.61 mM, and 1.49, and 1.29 mM, respectively, whereas for the shoot and root growth of barnyard grass the values were 4.09 and 2.41 mM, and 4.54 and 1.92 mM, respectively. Therefore, it is suggested that these compounds may contribute to the inhibitory effects of E. atropurpurea. [ABSTRACT FROM AUTHOR]

We report on room temperature, polarization-resolved Raman scattering measurements on layered crystals of the series MoSxSe(2-x) (0⩽x⩽2) grown by chemical vapor transport technique. The results reveal two distinct sets of features related to the E12g and A1g modes of pure members of series. As composition x changes, the in-plane E12gmode shows two-mode behavior, whereas the out-of-plane A1g mode presents more complex evolution. The MoSe2-like branch reveals the splitting associated with the altering arrangement of S and Se atoms around Mo and the resulting changes in the dipole moment of the molecule. The X-ray diffraction measurements confirm that the samples are single-phase materials of 2H-type structure over the entire range of the sulfide composition x, while the scanning transmission electron microscopy imaging reveals a random arrangement of the S and Se atoms. Modified random-element-isodisplacement model is adopted to predict the behavior of the individual modes in the alloys. The model successfully confirms the two-mode behavior exhibited by the MoSxSe(2-x) series. [ABSTRACT FROM AUTHOR]