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The insect population in grain stores can be kept under control by maintaining a high concentration of N2 gas throughout the grain bed. The development of controlled atmosphere storage technology for insect control requires an accurate prediction of the distribution of introduced gases in bulk grain. In this paper, based on the convective-diffusion model, the horizontal flow of N2, which was introduced into the paddy bulk in a large warehouse by means of the horizontal ventilation system, are modeled as fluid flow in a porous medium. The experimental data for N2 transfer and flow through ducts and bulk paddy were used to validate the model. The equations were solved using the finite difference method, and the predictions from the proposed model were in good agreement with the experimental results. The concentration distribution and flow uniformity of nitrogen in stored paddy were also analyzed during the nitrogen-filling procedure for CA storage. It was shown that it is feasible and practical to introduce nitrogen into stored bulk grain in a large warehouse by means of the horizontal ventilation system.

The stored-product pests are economically important that can be spread through grain trade. Most storedproduct pests, including eggs, nymphs, and adults, are very small and difficult to identify morphologically. Also the classification and identification of them have always been hindered by the overwhelming number of species, widely distribution. Here, we collected 43 stored-product pests from 46 geographical locations in China and other countries. The mtDNA COI gene sequences were sequenced. Software MEGA 5 was used to analyze the sequence comploition and genetic distances. Three molecular phylogenetic trees of Platypodidae were recomstructed using PAUP4.0 according to distance/ the neighbour-joining (NJ) and maximum parsimony (MP). The molecular results were compared with the morphological taxonomy. The interspecific genetic distance of the stored-product pests was significantly higher than the intraspecific genetic distance according to the barcoding gap analysis. This work provides a practical approach for the precise and rapid diagnosis of storedproduct pests.

The APETALA2/ethylene-responsive factor (AP2/ERF) transcription factor family is one of the largest transcription factor families in plants. Its subfamily members activate or repress the expression of related genes by specifically binding to cis-acting elements such as the GCC box and DRE/CRT in the promoter regions of downstream interacting genes, and participate in the regulation of biological processes such as growth and development, maturation and senescence, and stress response in fruits and vegetables. In recent years, an increasing number of studies have shown that AP2/ERF can also regulate the quality and resistance of fruits and vegetables by regulating target genes and inducing various phytohormone responses such as ethylene, jasmonic acid and salicylic acid, or by acting as a response factor in response to phytohormone signals. This article provides an overview of the structural characteristics of AP2/ERF transcription factors and their classification and distribution in fruits and vegetables and reviews the latest research progress in the regulatory effect of AP2/ERF on stress resistance in fruits and vegetables through interaction with the major hormone signals. It is our hope that this review will provide a theoretical basis for enhancing stress resistance in fruits and vegetables from the perspective of hormonal regulation of AP2/ERF transcription factors.

Layered transition-metal oxides have attracted intensive interest for cathode materials of sodium-ion batteries. However, they are hindered by the limited capacity and inferior phase transition due to the gliding of transition-metal layers upon Na+ extraction and insertion in the cathode materials. Here, we report that the large-sized K+ is riveted in the prismatic Na+ sites of P2-Na0.612K0.056MnO2 to enable more thermodynamically favorable Na+ vacancies. The Mn-O bonds are reinforced to reduce phase transition during charge and discharge. 0.901 Na+ per formula are reversibly extracted and inserted, in which only the two-phase transition of P2 ↔ P'2 occurs at low voltages. It exhibits the highest specific capacity of 240.5 mAh g-1 and energy density of 654 Wh kg-1 based on the redox of Mn3+/Mn4+, and a capacity retention of 98.2% after 100 cycles. This investigation will shed lights on the tuneable chemical environments of transition-metal oxides for advanced cathode materials and promote the development of sodium-ion batteries.

The practical applications of aqueous Zn/I2 batteries (AZIBs) operating within a wide temperature range are severely hindered by the uncontrolled shutting of polyiodide ions (I3−/ I5−) and rampant side reactions. In this study, a wide temperature tolerant polyanionic hydrogel (borax‐bacteria cellulose / p(AMPS‐AM)) with ion selective permeability is designed for inhibiting shutting effect and side reactions under extreme temperatures range from −50 to 50 °C. The zincophilic R−SO3− significantly enhances the transport of Zn2+ cations and promotes uniform growth of Zn metal along the (002) plane. Moreover, the abundant hydrophilic groups in hydrogels effectively suppress both the hydrogen evolution reaction and the formation of by‐products by reducing the water reactivity. Furthermore, theoretical calculations, visualization experiment and in situ Raman spectroscopy confirm that R−SO3− group effectively hinders the shuttle process of I3−/I5− anions through electrostatic repulsion. Consequently, this gel electrolyte facilitates the ultra‐stable Zn/I2 full cell at a low current density of 2 C over a wide temperature range of 100 °C. A Zn/I2 pouch cell with a low negative/positive capacity ratio of 3.3 exhibits a stable performance over 350 cycles with an impressive high‐areal capacity of 2.03 mA h cm−2, thereby establishing a solid foundation for its practical applications. [ABSTRACT FROM AUTHOR]