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Understanding the effect of H2O adsorption on reactant activation is of great importance in heterogeneous catalysis, which remains a grand challenge particularly in oxide catalyst systems with structural complexity. Herein, the effect of D2O adsorption on D2 activation over MgO nanocatalysts at different temperatures has been investigated by transmission Fourier transform infrared (FT-IR) and temperature-programmed desorption (TPD). Two sets of hydride and hydroxyl species produced from D2 dissociation at more active and less active Mg-O pairs can be observed by FT-IR, which all desorb via the product of D2 as confirmed by TPD experiments. We find that the physically adsorbed D2O overlayer does not affect the dissociation of D2 since D2 may pass through the molecular layer and access the surface-active sites. When D2O is partially dissociated on the MgO surface, D2 can only dissociate at the remaining active sites until that dissociated −ODw groups from D2O occupy all active sites. These findings provide a fundamental understanding of the effect of water adsorption on D2 activation on oxide catalysts. [ABSTRACT FROM AUTHOR]

Locusta migratoria is a serious agricultural pest in China. Beauveria bassiana is one of the most important pathogens of grasshoppers and locusts. The effects of ultraviolet light were evaluated on the B. bassiana strain BbZJ1. The results showed that 253.7 and 360 nm wavelength UV (Ultra Violet) did not affect the germination of B. bassiana after its recovery from UV treatments. Nevertheless, the virulence of B. bassiana BbZJ1 after its recovery from radiation of UV (253.7 nm) increased. The mortality rates were 85.00% for the BbZJ1 control, was 96.67% for BbZJ1 recovered from radiation of UV (253.7 nm) for 60 min. After treatment with 253.7 nm UV radiation for 60 min, the expression levels of stress-resistant genes BbAlg9 and Bbadh2 in BbZJ1 strain were 2.68 and 2.29 times higher than those in the control group, respectively. Meanwhile, the B. bassiana prepared in 5% groundnut oil showed highest tolerance levels to the ultraviolet radiation. The 5% groundnut oil was the most suitable potential UV-protectant for B. bassiana in terms of cost and availability. [ABSTRACT FROM AUTHOR]

Grapes (Vitis sp.) are susceptible to infection by grasshopper and fungus that lead to damaging productivity and economic losses. In this study, we infected the young and old leaf of grapevine by Acrida chinensis and Botrytis cinerea and combined the metabolomic and transcriptomic analysis to comprehend the infection-mediated molecular and metabolic responses. Results indicated that the metabolic reprogramming of lipid, proline, and carbohydrate metabolism is necessary for the biosynthesis of specialized metabolites, which are involved in grapevine defense response. Moreover, the resistance mechanisms of grapevine induced by grasshopper and Botrytis required the hormones crosstalk of abscisic acid (ABA), salicylic acid (SA), ethylene (ETH), brassinosteroid (BR), and jasmonic acid (JA). We also identified the different genes involved in resistance to pathogen and insect attack in transcriptional levels, which encoded pathogenesis-related proteins (PRs), disease resistance proteins (RPS), calcium-binding proteins (CMLs), WRKY transcription factor, abscisic acid-insensitive (ABI), brassinosteroid insensitive 1 (BAK1), ethylene-responsive transcription factor (ERF), leucine-rich repeat receptor-like protein kinases (LRRs), zinc finger protein (ZAT10), chitinase 5, and E3 ubiquitin-protein ligase PUB23 in infected leaves. Furthermore, we nominated various infection-related metabolic biomarkers, including glutathione, proline, aspartyl-L-proline, adenine, histidine, and arginine, that has major effects on the tolerance of leaf-damaging insects and pathogens. Taken together, our research results clarify that there are differences in the defense mechanisms of old leaves and young leaves that lead to different biological stress tolerance and provide deeper insights into grapevine regulatory network mediating defense response against infection caused by grasshopper and B. cinerea, and uncover the resistance mechanisms for functional genomic studies. [ABSTRACT FROM AUTHOR]

The wind environment is an important factor affecting the comfort of the outdoor environment in high-rise residential communities. The numerical simulation of ventilation situation in the outdoor environment could provide scientific bases for the design of various elements in a community, including space layout, roads, activity spaces, water system, and plants. Taking the Changqingteng community, Xinxiang as the object, this paper numerically simulates the wind environment in summer, winter, and the transition season on THSware VENT2018, and analyzes the wind speed amplification factors, wind speed vector diagrams, and wind speed cloud maps on the outdoor environment of the community. The results show that both wind speed and wind speed amplification factor fall into the comfortable ranges in most places of the community throughout the year. In summer, only a few windless activity spaces are uncomfortable on hot and humid days. In winter, multiple wind corridors appear in the north of the community. These corridors greatly suppress the comfort of residents, owing to their fast wind speed and large wind speed amplification factor. The following measures could be taken to optimize the outdoor environment of the community: adding leisure spaces around the water system to improve comfort in summer, and setting up wind barriers by planting dense evergreen plants between the buildings on the north side to improve comfort in winter. [ABSTRACT FROM AUTHOR]

Purpose: After the application of herbicides, their migration and transformation in the environment are closely related to their adsorption characteristics in the soil. The adsorption of herbicides in soil is also important when evaluating their environmental behaviors or risks. Pyraclonil is a contact herbicide widely used to control weeds in paddy fields, especially in Japan. This study investigated the adsorption and desorption behaviors of pyraclonil in eight typical agricultural soils across China. Materials and methods: Surface soil samples (0–15 cm) were collected in farmland across China, including Hebei luvisols, Heilongjiang phaeozems, Sichuan gleysols, Zhejiang anthrosols, Jiangxi ferralsols, Shandong alisols, Hubei lixisols, and Hainan plinthosols. Adsorption-desorption experiments were conducted at 25 °C ± 1 °C using a batch equilibration method. Pyraclonil residue was analyzed using high-performance liquid chromatography-mass spectrometry. Results and discussion: The adsorption and desorption isotherms of pyraclonil in the eight soils are fitted well by mathematical models. The isothermal adsorption-desorption curves of pyraclonil agree with the simulation results of the Freundlich model. The adsorption of pyraclonil is mainly physical, and all adsorption isotherms are of type L. The adsorption constants range from 3.2 to 28.6 mg1−1/n L1/n kg−1. The desorption curves of pyraclonil in all soils show positive hysteresis, as the hysteresis coefficients are in the range of 0.01–0.26. The adsorption and desorption constants increase with increasing soil organic matter content and cation exchange capacity, but they are not related to soil pH and clay content. Conclusions: Pyraclonil exhibits low adsorption in different agricultural soils, and the adsorption process is irreversible. Pyraclonil has moderate or high mobility in different agricultural soils (except phaeozems with high organic matter content) across China, and pyraclonil could be transported from soil to groundwater after its application. Therefore, pyraclonil poses some risks to surface water and groundwater. [ABSTRACT FROM AUTHOR]

Tetraniliprole (TTP) is a new bisimide-based insecticide. Three typical surface soil samples were collected in farmland across China, including Jiangxi red soil (RS), Shandong yellow brown soil (YBS), and Heilongjiang black soil (BS). Adsorption, desorption and leaching experiments were conducted by using equilibrium oscillation and soil column leaching methods at 25°C ± 1°C. The isothermal adsorption and desorption curves of TTP in the above three soils were in accordance with the Freundlich model. The adsorption/desorption constants (Kads−f/Kdes−f) were 41.96–64.48 and 3.62–43.65, respectively. There is a certain hysteresis in the desorption curve, and the hysteresis coefficient (H) was between 0.14 and 0.89. Besides, the leaching properties of TTP in three soils were different. The leaching of TTP in RS and YBS was easy, while difficult for BS. It is concluded that the different adsorption–desorption ability and leaching ability of TTP in the above three soils was attributed to the distinct contents of organic matter (OM) and cation exchange capacity (CEC) in soil. [ABSTRACT FROM AUTHOR]