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In order to improve the characteristics of uneven melting in the melting process of the horizontal latent heat energy storage system, the triplex-tube latent heat energy storage unit is taken as the research object, and the flip mechanism is applied to its melting process. Numerical simulation is used for the research, and the numerical model is verified by experimental data. The results show that under different dimensionless times, the melting performance of the unit can be significantly improved by a single flip. When the dimensionless time is 0.4576, it is found that the total melting time of the unit is reduced by 16.17 %, the average heat absorption rate is increased by 14.7 %, but the total heat energy absorption is reduced by 3.85 %. The results show that the addition of a flip can effectively shorten the melting time and increase the heat absorption rate, but it has a negative effect on the total heat absorption in one melting cycle. Moreover, through the comparison of dynamic flow rate, dynamic temperature response, and temperature interval, it is shown that the addition of flip effectively reduces the negative influence of the hard-to-melt zone on the melting performance of the unit during the melting process. The flip mechanism reduces the proportion of high-temperature phase change material in the melting process and makes the melting process more uniform.

In this work, solubilities were measured for R-1233zd(E) in PVE 68 oil between (283.15 and 343.15) K using an isochoric saturation method. The nonrandom two liquid (NRTL) model was applied to represent the solubility behavior of the R-1233zd(E)/PVE 68 oil mixture. According to the experimental data, we studied the differences in enthalpies between pure R-1233zd(E) and the R-1233zd(E)/PVE 68 oil mixture as well as the oil effect on the evaporator performance with different superheating and oil circulating mass fractions (Cg). In the pressure–enthalpy–vapor quality diagram, isotherm curves of pure R-1233zd(E) and the R-1233zd(E)/oil mixture have a separation point called the critical vapor quality that is mainly connected to solubility and Cg. Moreover, the enthalpy change rate (Rh) and nonevaporation quality (NEQ) are also associated with the solubility and Cg, especially at low superheating. A lower solubility and Cgwill result in higher Rhand lower NEQ, which are favorable to the refrigeration cycle.

Alfalfa (Medicago sativaL.) is a nutritious forage crop with wide ecological adaptability. The molecular breeding of alfalfa is restricted by its heterozygous tetraploid genome and the difficult genetic manipulation process. Under time and resource constraints, we applied a more convenient approach. We investigated two MtGA3oxgenes, MtGA3ox1and MtGA3ox2, of Medicago truncatula, a diploid legume model species, finding that MtGA3ox1 plays a major role in GA-regulated plant architecture. Mutation of neither gene affected nitrogenase activity. These results suggest that MtGA3ox1 can be used in semidwarf and prostrate alfalfa breeding. Based on the M. truncatula MtGA3ox1sequence, MsGA3ox1was cloned from alfalfa, and two knockout targets were designed. An efficient CRISPR/Cas9-based genome editing protocol was used to generate msga3ox1mutants in alfalfa. We obtained three lines that carried mutations in all four alleles in the T0 generation. Fifteen clonal plants were vegetatively propagated from each transgenic line using shoot cuttings. The plant height and internode length of msga3ox1null mutants were significantly decreased. The number of total lateral branches, leaf/stem ratio and crude protein content of aerial plant parts of msga3ox1mutants were significantly increased. Thus, we obtained semi-dwarf and prostrate alfalfa by gene editing.

Latent heat thermal storage (LHTS) system is a crucial technology for achieving carbon neutrality and alleviating energy stress. Although metal foam can ameliorate the thermal storage rate of the LHTS system, the impact of the inlet velocity and temperature of heat transfer fluid (HTF) on the phase transition of phase change material (PCM) needs to be properly designed to achieve optimal performance. A novel multi-channel LHTS tank with metal foam is designed. A three-dimensional numerical model is established to describe the transient melting process in the LHTS tank. Besides, a new LSTM-BP neural network is developed, in which the HTF inlet velocity, temperature and time are employed as input data. Simulated results are consistent with the previous measurement data, verifying the correctness of the numerical methods. Results suggest that the whole melting time of the PCM is diminishing with increasing HTF velocity (or temperature). The machine learning prediction results show minor differences with the simulation results. The developed machine learning model provides new adaptive approaches for thermal storage design and operation. [ABSTRACT FROM AUTHOR]