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A numerical simulation model of a natural ventilation greenhouse is helpful for improving the production and quality of greenhouse crops in tropical areas. Field experiments show that the mean coefficient of variation of indoor light intensity in four seasons was lower than 10.0%. The highest indoor temperature reached 39.3 °C during summer, while the average indoor temperature ranged from 24 °C to 26 °C in the other three seasons. The average relative humidity in the greenhouse ranged from 76% to 87% annually, which was higher and more stable than that in the external environment. A three-dimensional steady-state numerical model of the greenhouse was established based on computational fluid dynamics. Under natural ventilation conditions, the maximum error between the simulated value and the measured value of the temperature in each measuring point was 5.90%. And the average relative error between the simulated and measured values was 3.0% in the range of 0.7−1.5 m of crop cultivation height. Finally, a numerical simulation of adding side windows and expanding the vents was carried out. The results show that these methods can homogenize the airflow distribution in the greenhouse and improve the utilization efficiency of natural ventilation without more mechanical system operations. [ABSTRACT FROM AUTHOR]

The growth of Cu2O crystal planes was be controlled by adding surfactant to the NaCl solution in this manuscript. The structure and composition of the synthesized Cu2O particles were characterized by X‑ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM), and specific surface area test method (BET). The photocatalytic activities were evaluated by degrading methyl orange (MO) solution under magnetic stirring. The results shown that the synthesized Cu2O particle was spherical self-assembly structure when the surfactant was CTAB, and behaved higher degradation performance. Under dark conditions, the adsorption efficiency of 100 mg L–1 MO solution reached 67.08% in the first 1 min by 0.33 g L–1 CTAB-Cu2O, and after 15 min, the adsorption degradation efficiency of MO had reached 99.17%. The maximum adsorption capacity of CTAB-Cu2O was 297.28 mg g–1. The adsorption kinetics obeyed pseudo-second-order kinetics and followed the Freundlich isotherm. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: As the third generation new battery, the power conversion efficiency (PCE) of metal halide perovskite solar cells (PSCs) has increased from 3.8% in 2009 to 25.8% currently certified, which fully shows that they have great research value and development prospect. As one of the main components of high‐efficiency PSCs, hole transport materials (HTMs) play an important role in extracting and transporting holes and inhibiting charge recombination. However, commonly used HTMs require doping, and the hygroscopicity and corrosiveness of the dopants will destroy the stability of PSCs and hinder their commercialization. Therefore, it is of great significance to develop dopant‐free HTMs. In this review, the dopant‐free HTMs in recent six years are reviewed and summarized systematically, including organic small molecules, polymers and cross‐linkable materials. We focus on the design of the molecular cores and discuss their structure–property correlation, conductivity, and photovoltaic performance. Finally, how to design an ideal HTM is summarized. We hope that this review can provide reference for the development of low‐cost and dopant‐free HTMs to prepare efficient and stable PSCs. [ABSTRACT FROM AUTHOR]