159 research outputs found
Synthesis of thioesters through copper-catalyzed coupling of aldehydeswith thiols in water
Copper-catalyzed CâS bond formation between aldehydes and thiols in the presence of TBHP as an oxidant is described. Functional groups including chloro, trifluoromethyl, bromo, iodo, nitrile, ester and thiophene are all tolerated by the reaction conditions employed. This reaction is performed in water without the use of a surfactant. Both aryl and alkyl aldehydes couple suitably with aryl- and alkyl thiols, affording the corresponding thioesters in moderate to good yields
An eye tracking study of the application of gestalt theory in photography
Photography is an art form where integration of the human visual perception and psychological experiences result in aesthetic pleasure. This research utilizes eye tracking to explore the impact of the properties of Gestalt in photography on people's visual cognitive process in order to understand the psychological processes and patterns of photography appreciation. This study found that images with Gestalt qualities can significantly affect fixation, sightline distribution, and subjective evaluation of aesthetics and complexity. Closure composition images seem to make cognition simpler, resulting in the least number of fixation and saccades, longer fixation duration, and more concentrated sightline indicating stronger feeling of beauty, while images which portray similarity results in the greatest fixation and saccades, longest saccade duration, and greater scattering of sightline, indicating feelings of complexity and unsightliness. The results of this research are closely related to the theories of art and design, and have reference value for photography theory and application
A General Procedure for the Regioselective Synthesis of Aryl Thioethers and Aryl Selenides Through CâH Activation of Arenes
A general procedure for the synthesis of aryl thioethers and aryl selenides in one-pot through sequential iridium-catalyzed CâH borylation and copper-promoted CâS and CâSe bond formation is described. Functional groups including chloro, nitro, fluoro, trifluoromethyl, and nitrogen-containing heterocycles were all tolerated under the reaction conditions. Importantly, not only aryl thiols and selenides but also their alkyl analogs were suitable coupling partners, and the products were obtained in good yields with high meta regioselectivity
Manganese-Catalyzed Cross-Coupling of Thiols with Aryl Iodides
Here we report the manganesecatalyzedcoupling reaction of thiols witharyl iodides, giving the aryl thioethers ingood to excellent yields; the system showsgood functional group tolerance and enablesthe sterically demanding aryl iodides tocouple with thiols
Attractive or Faithful? Popularity-Reinforced Learning for Inspired Headline Generation
With the rapid proliferation of online media sources and published news,
headlines have become increasingly important for attracting readers to news
articles, since users may be overwhelmed with the massive information. In this
paper, we generate inspired headlines that preserve the nature of news articles
and catch the eye of the reader simultaneously. The task of inspired headline
generation can be viewed as a specific form of Headline Generation (HG) task,
with the emphasis on creating an attractive headline from a given news article.
To generate inspired headlines, we propose a novel framework called
POpularity-Reinforced Learning for inspired Headline Generation (PORL-HG).
PORL-HG exploits the extractive-abstractive architecture with 1) Popular Topic
Attention (PTA) for guiding the extractor to select the attractive sentence
from the article and 2) a popularity predictor for guiding the abstractor to
rewrite the attractive sentence. Moreover, since the sentence selection of the
extractor is not differentiable, techniques of reinforcement learning (RL) are
utilized to bridge the gap with rewards obtained from a popularity score
predictor. Through quantitative and qualitative experiments, we show that the
proposed PORL-HG significantly outperforms the state-of-the-art headline
generation models in terms of attractiveness evaluated by both human (71.03%)
and the predictor (at least 27.60%), while the faithfulness of PORL-HG is also
comparable to the state-of-the-art generation model.Comment: AAAI 202
Sensitivity Reach on the Heavy Neutral Leptons and -Neutrino Mixing at the HL-LHC
The model of heavy neutral leptons (HNLs) is one of the well-motivated models
beyond the standard model (BSM) from both theoretical and phenomenological
point of views. It is an indispensable ingredient to explain the puzzle of tiny
neutrino masses and the origin of the matter-antimatter asymmetry in our
Universe, based on the models in which the simplest Type-I seesaw mechanism can
be embedded. The HNL with a mass up to the electroweak scale is an attractive
scenario which can be readily tested in present or near-future experiments
including the LHC. In this work, we study the decay rates of HNLs and find the
sensitive parameter space of the mixing angles between the active neutrinos and
HNLs. Since the mixing between and HNL is not well established
in literature compared with those of and for the HNL of
mass in the electroweak scale, we focus on the channel to search for HNLs at the LHC 14
TeV. The targeted signature consists of three prompt charged leptons, which
include at least two tau leptons. After the signal-background analysis, we
further set sensitivity bounds on the mixing with at
High-Luminosity LHC (HL-LHC). We predict the testable bounds from HL-LHC can be
stronger than the previous LEP constraints and Electroweak Precision Data
(EWPD), especially for 50 GeV can reach down to .Comment: Published versio
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