4,114 research outputs found
4-Amino-1-(2-benzoyl-1-phenylÂethÂyl)-3-phenyl-1H-1,2,4-triazol-5(4H)-thione
In the title compound, C23H20N4OS, the two phenyl rings of the diphenylÂpropanone fragment form a dihedral angle of 86.8 (1)°, and the third phenyl ring attached to the triazole ring is twisted from the latter at 40.1 (1)°. In the crystal, molÂecules are paired into centrosymmetric dimers via pairs of interÂmolecular N—H⋯O and N—H⋯S hydrogen bonds
SearchMorph:Multi-scale Correlation Iterative Network for Deformable Registration
Deformable image registration can obtain dynamic information about images,
which is of great significance in medical image analysis. The unsupervised deep
learning registration method can quickly achieve high registration accuracy
without labels. However, these methods generally suffer from uncorrelated
features, poor ability to register large deformations and details, and
unnatural deformation fields. To address the issues above, we propose an
unsupervised multi-scale correlation iterative registration network
(SearchMorph). In the proposed network, we introduce a correlation layer to
strengthen the relevance between features and construct a correlation pyramid
to provide multi-scale relevance information for the network. We also design a
deformation field iterator, which improves the ability of the model to register
details and large deformations through the search module and GRU while ensuring
that the deformation field is realistic. We use single-temporal brain MR images
and multi-temporal echocardiographic sequences to evaluate the model's ability
to register large deformations and details. The experimental results
demonstrate that the method in this paper achieves the highest registration
accuracy and the lowest folding point ratio using a short elapsed time to
state-of-the-art
Additive manufacturing of monolithic microwave dielectric ceramic filters via digital light processing
Microwave dielectric ceramics are employed in filters as electromagnetic wave propagation media. Based on additive manufacturing (AM) techniques, microwave dielectric ceramic filters with complex and precise structures can be fabricated to satisfy filtering requirements. Digital light processing (DLP) is a promising AM technique that is capable of producing filters with high accuracy and efficiency. In this paper, monolithic filters made from Al2O3 and TiO2, with a molar ratio of 9:1 (0.9 Al2O3-0.1 TiO2), were fabricated by DLP. The difference in the dielectric properties between the as-sintered and post-annealed samples at different temperatures was studied. The experimental results showed that when sintered at 1550 °C for 2 h and post annealed at 1000 °C for 5 h, 0.9 Al2O3-0.1 TiO2 exhibited excellent dielectric properties: εr = 12.4, Q × f = 111,000 GHz, τf = +1.2 ppm/°C. After comparing the measured results with the simulated ones in the passband from 6.5 to 9 GHz, it was concluded that the insertion loss (IL) and return loss (RL) of the filter meet the design requirements
Investigating the driving forces of NOx generation from energy consumption in China
In China, nitrogen oxide (NOx) emissions have been declining in recent years, whereas NOx generation continues to increase. This has prompted a growing focus of policy design to inspect the driving mechanisms of NOx generation. In this study, a decomposition model of NOx generation in China from 1995 to 2014 was built using the Logarithmic Mean Divisia Index (LMDI) method. According to the decomposition results, technological effects (e.g., energy intensity and the sector generation factor) inhibited NOx generation in China, while gross domestic product (GDP) per capita was found to have the most positive effect on increasing NOx generation, accounting for 151.00% of the total change and showing an increasing trend in recent years. The sector structure of energy consumption always increased NOx generation, which contradicts the results of previous studies. All population effects considered in this study contributed to the growth in NOx generation. The population scale effect was increasingly impactful on the growth of NOx generation; the population spatial structure was active but less impactful. In general, technological impact cannot offset the increases caused by economic, structural, and population effects. Considering NOx reduction policy in China, more attention should be given to emission reduction policies, energy consumption, and socio-economic effects; together, these approaches will improve initiatives to reduce NOx
Stepped-height ridge waveguide MQW polarization mode converter monolithically integrated with sidewall grating DFB laser
We report the first demonstration of a 1555 nm stepped-height ridge waveguide
polarization mode converter monolithically integrated with a side wall grating
distributed-feedback (DFB) laser using the identical epitaxial layer scheme.
The device shows stable single longitudinal mode (SLM) operation with the
output light converted from TE to TM polarization with an efficiency of >94%
over a wide range of DFB injection currents (IDFB) from 140 mA to 190 mA. The
highest TM mode purity of 98.2% was obtained at IDFB=180 mA. A particular
advantage of this device is that only a single step of metalorganic vapor-phase
epitaxy and two steps of III-V material dry etching are required for the whole
integrated device fabrication, significantly reducing complexity and cost
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