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Nitration of O -methylisouronium sulfate under mixed acid conditions gives O -methyl- N -nitroisourea, a key intermediate of neonicotinoid insecticides with high application value. The reaction is a fast and highly exothermic process with a high mass transfer resistance, making its control difficult and risky. In this paper, a homogeneous continuous flow microreactor system was developed for the nitration of O -methylisouronium sulfate under high concentrations of mixed acids, with a homemade static mixer eliminating the mass transfer resistance. In addition, the kinetic modeling of this reaction was performed based on the theory of NO 2 + attack, with the activation energy and pre-exponential factor determined. Finally, based on the response surface generated by the kinetic model, the reaction was optimized with a conversion of 87.4% under a sulfuric acid mass fraction of 94%, initial reactant concentration of 0.5 mol/L, reaction temperature of 40 °C, molar ratio of reactants at 4.4:1, and a residence time of 12.36 minutes., (Copyright © 2024, Guo et al.)

Based on the analysis of the airborne bistatic synthetic aperture radar (SAR) imaging geometric mode, an extended nonlinear chirp scaling algorithm is employed to simulate and verify the imaging effect of the bistatic SARs. A gradient theory-based two-dimensional resolution bistatic SAR model is proposed, and the constraints of the multi-platform flight trajectory parameters meeting the imaging accuracy of the bistatic SAR are analyzed. Finally, through the bistatic SAR imaging simulation of cooperative flight trajectories under various situations, the spatial configuration constraint envelope between the flight vehicles to achieve the optimal resolution is revealed. The results of this paper will provide a theoretical reference for the SAR application in formation flight control.

With the rapid development of economy and society and the continuous optimization of industrial structure, the demand for high skilled talents is increasing. Education plays an irreplaceable role in China's economic growth. Therefore, it is of great significance to study the impact of talent supply of vocational education on economic growth from the perspective of human capital and comprehensively consider the spatial interaction of economic growth. Taking intelligent image recognition technology as the main research technology, this paper discusses the contribution of educational human capital to regional green economic growth. This paper expounds the content of intelligent image recognition technology, constructs an image recognition system based on neural network, and studies the relationship between human resource utilization efficiency and regional economy under intelligent image recognition technology based on the empirical analysis of intelligent image recognition technology. Finally, it makes an empirical study on the spatial effect in the image recognition system and expounds the relationship between feature space and economic growth. It verifies the relationship between educational human capital and green economic growth. The results show that the intelligent image recognition technology has a good effect in the research of spatial effect., Competing Interests: The author declares that there are no conflicts of interest regarding this work., (Copyright © 2021 Jiapeng Guo.)

Aldehyde dehydrogenase 2 (ALDH2) plays important role in ethanol metabolism, and also serves as an important shield from the damage occurring under oxidative stress. A special inactive variant was found carried by 35-45% of East Asians. The variant carriers have recently been found at the higher risk for the diseases related to the damage occurring under oxidative stress, such as cardiovascular and cerebrovascular diseases. As a result, ALDH2 activators may potentially serve as a new class of therapeutics. Herein, N-benzylanilines were found as novel allosteric activators of ALDH2 by computational virtual screening using ligand-based and structure-based screening parallel screening strategy. Then a structural optimization was performed and has led to the discovery of the compound C6. It has good activity in vitro and in vivo, which could reduce infarct size by ∼70% in ischemic stroke rat models. This study provided good lead compounds for the further development of ALDH2 activators., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Masson SAS. All rights reserved.)

The colchicine site inhibitors (CSIs) displayed both antimitotic and vascular disrupting activities, therefore are promising potential antitumor agents. In this study, a series 1-phenyl-4,5-dihydro-2H-benzo[e]indazoles were found as new CSIs of which the bioactive configuration was locked. Among them, compounds C1 and C2 displayed the best activity, with tubulin polymerization IC 50 of 3.4 and 1.5 μM, and growth IC50 of low nanomolar concentrations against human colon cancer cell lines. In addition, compound C1 showed excellent broad-spectrum antitumor activity in the NCI-60 Human Tumor Cell Lines Screen, encouraging further study of this antitumor compound., (Copyright © 2019 Elsevier Ltd. All rights reserved.)