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【Objective】 The variation in evapotranspiration is an important parameter in irrigation design. In this paper, we propose and verify a modified single crop coefficient method to calculate the evapotranspiration of greenhouse lettuce. 【Method】 The experiment was conducted in autumn from 2021 to 2022 in a greenhouse grown with lettuce. The crop coefficient was calculated using the formula recommended by FAO-56, with the calculated crop coefficient for initial growth stage being modified based on ET0 and irrigation frequency, while for other growing stages it was modified based on meteorological factors and plant height. The modified single crop coefficient was then used to calculate the evapotranspiration of the lettuce, with the calculated results being validated against measured data from weighing lysimeters. 【Result】 The mean reference crop evapotranspiration (ET0) of the lettuce varied between 1.18 to 2.44 mm/d, but showed a decreasing trend from 2021 to 2022. The modified crop coefficient and measured crop coefficient both peaked at the initial stage, with their associated two-year average being 0.74±0.13 and 0.76±0.13, respectively. As the crop grew, both crop coefficients asymptotically decreased to 0.5~0.6 in the middle and later growing stages. The modified crop coefficient was closer to the measured crop coefficient than that calculated from the formula recommended by the FAO-56, with the relative error between them ranging from -6.7% to 5.4%. The mean estimated and the measured evapotranspiration of the lettuce in autumn were 1.310 mm/d and 1.283 mm/d, respectively. The determination coefficient, the mean absolute error, root mean square error and the index of the agreement between the measured and estimated evapotranspiration were 0.975, 0.176 mm/d, 0.222 mm/d and 0.955, respectively. 【Conclusion】 The modified single crop coefficient is more accurate than that calculated from the formula recommended by the FAO-56 for estimating the evapotranspiration of greenhouse lettuce.

【Objective】 Surface water evaporation (Ep) in greenhouse is often used as a reference in irrigation management. The purpose of this paper is to present a model to estimate it. 【Method】 The model was derived based on meteorological data and pan-evaporation measured from March to July in 2020 and 2022. The relationship between Ep and meteorological data was analyzed using the principal component method, from which a multiple linear regression model was developed to estimate Ep. 【Result】 Ep increased as time elapsed, with its average increasing from the range of 1.84~1.94 mm in March to the range of 3.77~5.15 mm in June in both 2020 and 2022. Ep was influenced by radiation and relative humidity the most. Photosynthetically active radiation had the highest correlation with Ep, with their correlation coefficient being 0.852 (P

99Tc has a long half-life, high fission yield, and good environmental mobility, posing a significant threat to the environment and human health. Therefore, removing technetium from radioactive wastewater is a very important and urgent task. For laboratory safety reasons, ReO4− is often used as a non-isotopic substitute for 99TcO4−. From this point of view, the study of the separation behavior of Re in the aqueous phase can provide a reference value for the removal of 99Tc. Here, a new type of extraction chromatography resin was prepared by impregnating the functionalized ionic liquid into the macroporous resin, whose imidazolium cations modified by amide functional groups which can effectively capture ReO4−/TcO4− from simulated radioactive wastewater. The results show the resin has good adsorption performance and fast adsorption kinetics (the adsorption equilibrium is about 20 min). The adsorption mechanism was investigated using Fourier transform infrared (FT-IR) spectra and X-ray photoelectron spectroscopy (XPS). It shows that the adsorption process is an anion exchange between Cl− in the resin and ReO4− in the solution. [ABSTRACT FROM AUTHOR]

In the 3D ferroelectric memory fabrication process, the outer Titanium nitride metal electrode and silicon doped hafnium-based ferroelectric layer will produce void defects at the interfaces, causing increased leakage and compromising device performance. These void defects are caused by the volume contraction during the phase transition process, which leads to tension at the outer interface of the 3D ferroelectric capacitor structure. Due to the unavoidable structural stress, it is necessary to optimize the interface bonding energy. First principles simulation revealed insufficient binding energy between titanium nitride and silicon doped hafnium oxide ferroelectric materials, while introducing an amorphous alumina interface layer can effectively improve the binding ability. Experimental verification has confirmed that using an amorphous alumina interface layer as an adhesive layer can successfully solve the interface void defects, thereby improving the ferroelectric properties in three-dimensional structures. [ABSTRACT FROM AUTHOR]

The aim of this study was to explore the feasibility of quantitatively evaluating a sapphire's color by analyzing gemstone images. The color characteristics of gemstones through photography and color extraction were accurately captured, and the key color parameters for different color regions of gemstones were extracted. Then, the color of sapphires was simulated by statistical method and function simulation method. The results indicate that the brightness value of the bright area was the highest and the chroma value of the "fire" area was the highest. The chroma (C) of the sapphires was linearly positively correlated with the absolute value of its b value, and the brightness (L) showed a quadratic correlation with its chromaticity parameters (b or C). The function simulation method with an average of b as the main independent variable had a larger standard deviation, which proves that this method has a stronger ability to distinguish the differences in a sapphire's color. This method can be extended to the color evaluation of other colored gemstones, and it can be used to form a gemstone color evaluation system. [ABSTRACT FROM AUTHOR]