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Mechanization is the inevitable future of tea harvesting, but its impact on tea chemistry and quality remains uncertain. Our study examines untargeted metabolomic data from 185 oolong tea products (Tieguanyin) made from leaves harvested by hand or machine based on UPLC-QToF-MS analysis. The data revealed a minimum 50% loss for over half of the chemicals in the machine-harvested group, including catechins, theaflavin, gallic acid, chlorogenic acid, and kaempferol-3-gluocside. Integrating sensory evaluation, OPLS-DA identified the six most important metabolites as significant contributors to sensory decline caused by harvesting mechanization. Furthermore, our research validates the possibility of using DD-SIMCA modelling with untargeted metabolomic data for distinguishing handpicked from machine-harvested tea products. The model was able to achieve 93% accuracy. This study provides crucial insights into the chemical and sensory shifts during mechanization, along with tools to manage and monitor these changes. [ABSTRACT FROM AUTHOR]

Experimental investigations and density functional theory (DFT) calculations were carried out to study the comprehensive effect of different 3,5-heptanedioldibenzoate (HDDB) optical isomers as the internal electron donor on the catalytic performance of Ziegler−Natta catalysts. The experimental catalytic activity of HDDB has a positive correlation with the relative content of the mesomer incorporated during catalyst preparation, while the hydrogen response of HDDB displayed a negative correlation with the relative content of the mesomer. In order to apply the DFT calculation results to the macroscopic activity of the catalyst, the content of the active centers of the catalyst was analyzed. Assuming that the content of the active centers is proportional to the internal electron donor content of the catalyst, binary linear regression was carried out, which showed a good linear correlation between experimental activity data and internal electron donor content. Furthermore, the fitted activity of the single active centers aligned well with the calculated activation energies. These results revealed that the catalytic activity of polypropylene (PP) catalysts is dependent on both the active center content and the catalytic activity of an individual active center. Additionally, the lower hydrogen response of HDDB leads to a higher molecular weight of polypropylene obtained from the RS-containing catalyst compared to the SS-containing catalyst. Further study reveals that the hydrogen transfer reactions of 2,4-pentanediol dibenzoate (PDDB)/HDDB are influenced by the orientation of the methyl/ethyl groups in different isomers, which affect the activation energy differences between the hydrogen transfer reaction and the propylene insertion reaction, and finally influence the molecular weight of PP. [ABSTRACT FROM AUTHOR]

This study explored the overall visual elements of arcade buildings and streetscapes from the perspective of tourists and then evaluated their influence on the identity and emotion of places. The scope of the research was to take the arcade building in the port area of Shantou Small Park in Guangdong, China, and apply the eye-tracking experiment method and semantic difference method. This entailed collecting the eye-tracking data of 16 people, implementing 334 questionnaires for evaluation, verifying the correlation between the visual elements and place identity emotions, and then screening out the visual elements that affect place identity through correlation analysis and multiple linear regression analysis. The results show that plaque text morphological richness (p = 0.045 < 0.05, and the regression coefficient B = 0.146), the color brightness of plaque text (p = 0.031 < 0.01, and the regression coefficient B = 0.171), window morphological richness (p = 0.038 < 0.05, and the regression coefficient B = 0.106), window color brilliance (p = 0.047 < 0.01, and regression coefficient B = 0.094), and plant color brilliance (p = 0.029 < 0.05, and the regression coefficient B = 0.154) are five visual element evaluation factors that have a significant correlation with the identity and emotion of places. Although the fineness of architectural decoration is negatively correlated with place identity, it is not obviously significant. The research results provide reference for the visual control design of arcade buildings. [ABSTRACT FROM AUTHOR]

Confronting the age of artificial intelligence, exploring art through technology has become one of the directions of interdisciplinary development. Not only does artificial intelligence technology explore sustainability on a technical level; it can also take advantage of itself to focus on the visual perception of the living environment. People frequently interpret environmental features through their eyes, and the use of intuitive eye-tracking can provide effective data that can contribute to environmental sustainability in managing the environment and color planning to enhance the image of cities. This research investigates the visual responses of people viewing the historic city of Macau through an eye movement experiment to understand how the color characteristics of the physical environment are perceived. The research reveals that the buildings and plantings in the historic district of Macau are the most visible objects in the environment, while the smaller scale of St. Dominic's Square, the Company of Jesus Square, and St. Augustine's Square, which have a sense of spatial extension, have also become iconic environmental landscapes. This also draws visual attention and guides the direction of travel. The overall impressions of the Historic Centre of Macau, as expressed by the participants after the eye movement experiment, were mainly described as "multiculturalism", "architectural style", "traditional architecture", "color scheme", and "garden planting". The 60 colors representing the urban color of Macau are then organized around these deep feelings about the environment. Therefore, for future inspiration, the 60 colors can be applied through design practice to create color expressions that fit the local characteristics, and thereby enhance the overall visual image of the city. [ABSTRACT FROM AUTHOR]