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• This study presents a new approach for the application of shallow geothermal energy. • Difference in temperatures of heat pipe systems with different diameter of vertical part is insignificant. • The heat resistance of the heat pipes only accounted for approximately 1% of the total thermal resistance. • The maximum heat transfer power of the heat pipe is 202 W. Owing to the depletion of global fossil energy and the increasing environmental awareness of environmental protection, the use of shallow geothermal energy has been receiving widespread attention. In this study, two sets of groundwater-based heat pipe (GBHP) systems were fabricated to explore the application of heat pipes in shallow geothermal energy and tested through lawn heating experiments during the winter. Results of the experiment showed that the vertical diameter of the heat pipe did not have any significant effect on its heat transfer performance, and the maximum difference in temperature between the horizontal section of the east and west heat pipes during the observation period was 1.6 °C. Furthermore, the heat pipe exhibited good isothermicity with a constant operation, with the average temperature difference between the condensation and evaporation sections were 2.1 °C. The heat pipe also exhibited good thermal conductivity, the thermal resistance accounting for only 1% of the total thermal resistance in the heat transfer process. The maximum heat transfer power of a single heat pipe was found to be 202 W. This study presents a new approach for the application of shallow geothermal energy. [ABSTRACT FROM AUTHOR]

Summary: Fruits and vegetables (F&V) provide people with a variety of essential vitamins, antioxidants and dietary fibre, thus constituting integral components of human diet. With the surge of interest in F&V, their consumption ratio has kept increasing in recent years. Unfortunately, microorganisms and pesticide residues on the surfaces of F&V may be hazardous to humans. As an emerging technology, electrolysed water (EW) shows great application potential in reducing these hazards. EW treatment not only effectively removes microorganisms from F&V but also degrades pesticide residues on their surfaces. In addition, EW treatment affects the physiological metabolism of harvested F&V, which is conducive to maintain their sensory quality and nutritional value. This article reviews the principles of EW preparation, advantages and disadvantages, and the application of EW in F&V in the last decade, including disinfection of irrigation water, removal of pesticide residues, disinfection after harvest its effects on physicochemical parameters and enzyme activity of F&V, etc. Moreover, the combination of EW and other technology, including ozone, short‐time heat treatment, ultraviolet irradiation and ultrasound, to further improve the quality control effects of F&V is discussed. [ABSTRACT FROM AUTHOR]

In this work, to evaluate the role of acidic electrolyzed water (AEW) combined with vacuum precooling (VP) treatment in fresh goji preservation, the physicochemical properties and anti‐oxidation indexes of goji berries were compared between the AEW+VP‐treated and control (VP treatment) groups during storage at 4, 7, and 10°C. The results showed that AEW+VP could effectively inhibit the decrease in L* and a* values, reduce the respiratory rate, delay the loss of vitamin C content, and maintain higher total soluble solid (TSS) content. Compared to the control, AEW+VP‐treated goji maintained higher catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) activity. Therefore, AEW+VP treatment could effectively improve the storage quality and extend the shelf life of fresh goji berries. Practical applications: Acidic electrolyzed water, a clean and environmentally friendly preservation technology, combined with vacuum precooling extended the shelf life of fresh goji berries while delaying the aging of goji berries at different storage temperatures. In this sense, AEW+VP had certain stability in enhancing the storage quality and extending the shelf life of goji berries, which can be regarded as an effective strategy for promoting the preservation of agricultural products. [ABSTRACT FROM AUTHOR]

Near infrared hyperspectral imaging (NIR‐HSI) with a spectral range of 900 to 1700 nm was for the first time used to predict the changes of sugar content in Lingwu jujube during storage. Monte Carlo method was adopted to detect outliers, and multiple scattering correction (MSC), standard normal variate transformation (SNV), and Baseline were used to optimize modeling. Competitive adaptive reweighted sampling (CARS), interval variable iterative space shrinkage approach (iVISSA), and interval random frog (IRF) were used to select optimal wavelengths. In addition, partial least square regression (PLSR) and support vector machine (SVM) modeling based on optimal wavelengths were compared. The results showed that 30, 30, and 24 wavelengths were selected by CARS; 106, 87, and 112 feature wavelengths were selected by iVISSA; and 96, 71, and 83 optimal wavelengths were selected by IRF for sucrose, fructose, and glucose, respectively. The CARS–PLSR models provided the best results for fructose and glucose, and iVISSA–SVM model was better for sucrose. The results indicated that NIR–HSI model may be used as a rapid and nondestructive method for the determination of sugar content in jujubes. [ABSTRACT FROM AUTHOR]

To investigate the changes in colour and chlorophyll levels in vacuum-precooled green beans during storage, kinetic models and shelf life prediction models of these quality indices were established by reaction kinetics and the Arrhenius equation. Linear regression analysis was used to study the changes in colour and chlorophyll levels during 12 d of storage at 0 °C, 5 °C, 10 °C and 25 °C, and the relationship between chlorophyll level and total colour difference (ΔE) was also determined. The results showed that the colour and chlorophyll levels retained in vacuum-precooled green beans were better than those in the control group during storage. A linear regression analysis revealed that the change rate constants of colour parameters (L*, a*, b* and ΔE) and chlorophyll levels followed the Arrhenius law dependence on temperature. Colour and chlorophyll levels were successfully described by zero-order and first-order reactions, respectively. In addition, the shelf life based on ΔE and chlorophyll level changes of 10% was similar to that at a cut-off score of 6 by sensory evaluation. It was suggested that the kinetics model could accurately predict the shelf life and changes of colour and chlorophyll levels in vacuum-precooled green beans during storage. • Vacuum precooling resulted in higher retention colour of green beans during storage. • Kinetics modelling was used to map green beans color changes during storage. • The applicability of the Arrhenius law during storage was investigated. • Chlorophyll was a predictor of colour quality index during storage. [ABSTRACT FROM AUTHOR]