7,407 research outputs found
3-Ethyl-4-[(E)-2-methylbenzylideneamino]-1H-1,2,4-triazole-5(4H)-thione
Crystals of the title compound, C12H14N4S, were obtained from a condensation reaction of 4-amino-3-ethyl-1H-1,2,4-triazole-5(4H)-thione and 2-methylbenzaldehyde. In the molecular structure, there is a short N=C double bond [1.255 (2) Å], and the benzene and triazole rings are located on opposite sites of this double bond. The two rings are approximately parallel to each other, the dihedral angle being 1.75 (11)°. A partially overlapped arrangement is observed between the nearly parallel triazole and benzene rings of adjacent molecules; the perpendicular distance of the centroid of the triazole ring from the benzene ring is 3.482 Å, indicating the existence of π–π stacking in the crystal structure
(E)-2-Acetylpyrazine 4-nitrophenylhydrazone
In the title compound, C12H11N5O2, the molecule adopts an E configuration, with the benzene and pyrazine rings located on opposite sides of the N=C double bond. The face-to-face separations of 3.413 (14) and 3.430 (8) Å, respectively between parallel benzene rings and between pyrazine rings indicate the existence of π–π stacking between adjacent molecules. The crystal structure also contains N—H⋯N and C—H⋯O hydrogen bonding
2-Methylbenzaldehyde 2-methylbenzylidenehydrazone
The molecule of the title compound, C16H16N2, is centrosymmetric and the dihedral angle between the benzene ring and the dimethylhydrazine mean plane is 16.11 (15)°
Mask-guided modality difference reduction network for RGB-T semantic segmentation
By exploiting the complementary information of RGB modality and thermal modality, RGB-thermal (RGB-T) semantic segmentation is robust to adverse lighting conditions. When fusing features from RGB images and thermal images, the existing methods design different feature fusion strategies, but most of these methods overlook the modality differences caused by different imaging mechanisms. This may result in insufficient usage of complementary information. To address this issue, we propose a novel Mask-guided Modality Difference Reduction Network (MMDRNet), where the mask is utilized in the image reconstruction to ensure that the modality discrepancy within foreground regions is minimized. Doing so enables the generation of more discriminative representations for foreground pixels, thus facilitating the segmentation task. On top of this, we present a Dynamic Task Balance (DTB) method to balance the modality difference reduction task and semantic segmentation task dynamically. The experimental results on the MFNet dataset and the PST900 dataset demonstrate the superiority of the proposed mask-guided modality difference reduction strategy and the effectiveness of the DTB method
SN 2018gk Revisited: the Photosphere, the Central Engine, And the Putative Dust
In this paper, we perform a comprehensive study for the physical properties
of SN 2018gk which is a luminous type IIb supernova (SN). We find that the
early-time photospheric velocity vary from a larger value to a smaller value
before the photosphere reach a temperature floor. We generalize the photosphere
modulus and fit the multi-band light curves (LCs) of SN 2018gk. We find that
the Ni mass model require M of Ni which is
larger than the derived ejecta mass ( M). Alternatively, we
use the magnetar plus Ni and the fallback plus Ni models to fit
the LCs of SN 2018gk, finding that the two models can fit the LCs. We favor the
magnetar plus Ni since the parameters are rather reasonable ( M, M which is smaller than the upper
limit of the value of the Ni mass can by synthesized by the
neutrino-powered core collapse SNe G which is comparable
to those of luminous and superluminous SNe studied in the literature, and
ms which is comparable to those of luminous SNe), while the
validity of the fallback plus Ni model depends on the accretion
efficiency (). Therefore, we suggest that SN 2018gk might be a SN IIb
mainly powered by a central engine. Finally, we confirm the NIR excesses of the
spectral energy distributions (SEDs) of SN 2018gk at some epochs and constrain
the physical properties of the putative dust using the blackbody plus dust
emission model.Comment: 26 pages, 11 figures, 5 tables, Accepted for publication in Ap
(E)-N′-[1-(4-Aminophenyl)ethylidene]benzohydrazide
Crystals of the title compound, C15H15N3O, were obtained from a condensation reaction of benzohydrazide and 1-(4-aminophenyl)ethanone. The molecule assumes an E configuration with the aminophenyl and benzohydrazide units located on opposite sites of the C=N double bond. In the crystal structure, the benzene rings of the molecule are slightly twisted with respect to the central hydrazide, the dihedral angles being 18.22 (12) and 27.62 (12)°. The crystal structure contains intermolecular N—H⋯O and weak C—H⋯N hydrogen bonding
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