3,423 research outputs found
Anisotropic Topological Hall Effect with Real and Momentum Space Berry Curvature in the Antiskrymion Hosting Heusler Compound MnPtSn
The topological Hall effect (THE) is one of the key signatures of
topologically non-trivial magnetic spin textures, wherein electrons feel an
additional transverse voltage to the applied current. The magnitude of THE is
often small compared to the anomalous Hall effect. Here, we find a large THE of
0.9 cm that is of the same order of the anomalous Hall effect in the
single crystalline antiskyrmion hosting Heusler compound MnPtSn, a
non-centrosymmetric tetragonal compound. The THE is highly anisotropic and
survives in the whole temperature range where the spin structure is noncoplanar
(<170 K). The THE is zero above the spin reorientation transition temperature
of 170 K, where the magnetization will have a collinear and ferromagnetic
alignment. The large value of the THE entails a significant contribution from
the momentum space Berry curvature along with real space Berry curvature, which
has never been observed earlier
Steel Industry-Wastes as New Materials for Road Construction
A large number of steel plants have been set up in India and they are producing several million tonnes of iron and steel. However, the production of iron and steel is always associated with the generation of waste materials like air cooled slag, steel slag, granulated slag and flyash etc. These materials are posing serious problems of disposal and causing environmental pollution. Road Construction is one such sector where these materials can be utilised in bulk. CRRI started a few projects sponsored by Steel Authority of India Limited (SAIL), and all these materials were tested on a big scale in CRRI laboratory. Based on the success of laboratory results, various combinations were tried in the field and finally a road was constructed. This road has been monitored regularly for surface unevenness and pavement structural strength. This paper gives the results of extensive laboratory investigations and performance of the road
N-(3-Chloro-4-fluorophenyl)-2-(naphthalen-1-yl)acetamide
In the title compound, C18H13ClFNO, the dihedral angle between the mean planes of the chloro- and fluoro-substituted benzene ring and the naphthalene ring system is 60.5 (8)°. In the crystal, molecules are linked by N—H⋯O hydrogen bonds, forming a zigzag chain along [101]
(2E)-1-(2,6-Dichloro-3-fluorophenyl)-3-(4-methoxyphenyl)prop-2-en-1-one
There are two independent molecules in the asymmetric unit of the title compound, C16H11Cl2FO2. The F atom equally populates both meta positions of the 6-dichloro-3-fluorophenyl ring in each molecule, resulting in 0.5 occupancy for both the F and H atoms in these positions. The dihedral angle between the mean planes of the benzene rings are 77.5 (2) and 89.8 (8)°in the two molecules. In the crystal, weak C—H⋯F and C—H⋯O interactions involving the half-occupied H and F atoms are observed. Weak π–π stacking interactions [centroid—centroid distance = 3.150 (2) Å] also contribute to the crystal stability
Plantlets from mesophyll protoplasts of Solanum xanthocarpum
Young leaves of Solanum xanthocarpum from axenic shoot cultures released viable protoplasts when treated with appropriate enzymes. The protoplasts on culture in modified Murashige and Skoog (1962) medium supplemented with 2,4-dichlorophenoxy-acetic acid (0.5 mg/l), naphtha leneacetic acid (1 mg/l), kinetin (1 mg/l) and organic nutrients of KM (Kao and Michayluk 1975) regenerated to form callus tissue as a result of repeated divisions. Protoplast-derived calli differentiated into shoots on MS medium enriched with kinetin (0.5 mg/l) and rooting could be initiated by transferring the shoot-buds to basal medium
Strain in Silica-Supported Ga(III) Sites : Neither Too Much nor Too Little for Propane Dehydrogenation Catalytic Activity
Altres ajuts: Acord transformatiu CRUE-CSICWell-defined Ga(III) sites on SiO are highly active, selective, and stable catalysts in the propane dehydrogenation (PDH) reaction. In this contribution, we evaluate the catalytic activity toward PDH of tricoordinated and tetracoordinated Ga(III) sites on SiO by means of first-principles calculations using realistic amorphous periodic SiO models. We evaluated the three reaction steps in PDH, namely, the C-H activation of propane to form propyl, the β-hydride (β-H) transfer to form propene and a gallium hydride, and the H-H coupling to release H, regenerating the initial Ga-O bond and closing the catalytic cycle. Our work shows how Brønsted-Evans-Polanyi relationships are followed to a certain extent for these three reaction steps on Ga(III) sites on SiO and highlights the role of the strain of the reactive Ga-O pairs on such sites of realistic amorphous SiO models. It also shows how transition-state scaling holds very well for the β-H transfer step. While highly strained sites are very reactive sites for the initial C-H activation, they are more difficult to regenerate. The corresponding less strained sites are not reactive enough, pointing to the need for the right balance in strain to be an effective site for PDH. Overall, our work provides an understanding of the intrinsic activity of acidic Ga single sites toward the PDH reaction and paves the way toward the design and prediction of better single-site catalysts on SiO for the PDH reaction. We performed computational calculations of Ga(III) single sites on realistic amorphous models of SiO to evaluate their catalytic activity toward the propane dehydrogenation reaction. Our results show that a balance in strain is key, in which neither too stiff nor too loose Ga−O bonding is needed to obtain the highest catalytic activity
- …