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In this work, we introduce the VR[superscript 2]E[superscript 2]C system for Virtual Reality Remote Education for Experimental Chemistry. It aims to increase scientific literacy about remote education of theoretical and experimental chemistry among the public and high school students. It provides a laboratory option for students with disabilities who are keen on chemistry experiments but have limited mobility. VR[superscript 2]E[superscript 2]C provides three modes to accomplish the training: users can choose to control the intelligent robot to finish the experimental operations by instruction or choose to watch the experiments automatically conducted by VR[superscript 2]E[superscript 2]C. The experimental results can be delivered to users in real time or later. This system provides remote education for safe and high fault-tolerant experimental topics, demonstrating how the latest VR and robotics technology could benefit traditional chemical education.

Objective: To find the most suitable cooling rate to meet people's requirements for apple storage quality at low temperature. Methods: The changes of apple tissue and cell structure were observed by low-temperature cold table equipment, and the changes of freezing temperature before and after cooling were compared and analyzed. Meanwhile, the changing trends of area, roundness, circumference, diameter, deformation, volume and internal pressure were compared and analyzed. Results: With the increase of cooling rate, the freezing temperature and freezing time of apple cells decreased gradually. The morphological parameters of apple cells changed with the increase of cooling rate, and the change trend was the same. Conclusion: The optimum cooling rate of apple cells was 10 ℃/min.

Objective: Aims at the brittleness regulation of fruit and vegetable slices during hot air drying process. Methods: This article takes fresh potatoes and bananas as the research materials, adopts mechanical and acoustic measuring devices to collect mechanical and acoustic signals generated by the fruit and vegetable slice samples at the mechanical compression mode, which were collected at different drying times during the hot air drying process of 80 ℃, to comprehensively evaluate the fragility of the fruit and vegetable slices. Results: The acoustic emission （AE） signal of the potato slice appeared the drying time of 45 min, and its AE energy increased gradually with the increase of drying time. The stress increased rapidly and then remained stable; The best drying end time of potato was 180 min. At this time, the AE energy and force were 255.38 mV·ms and 20.25 N respectively. The AE signal of the banana slices appeared from the early stage of drying, and its energy increased rapidly with the progress of drying, decreased after 150 min of drying, and remained stable after 200 min. The stress appeared after drying for 60 min, increased rapidly until the peak at 240 min, and remained stable. The optimum drying end time of banana slices was 240 min, and the energy and force were 122.58 mV·ms and 18.01 N, respectively. Conclusion: The mechanical-acoustic detecting method can be used to monitor the crispness variation of the fruit and vegetable slices being dried and to optimize the hot air drying process.

The widespread use of tetracycline (TC) poses potential hazards to ecosystems and human health. In this study, ZIF-67 was successfully synthesized using a room-temperature static synthesis method and applied to the efficient removal of TC from water. It was shown that the maximum adsorption of TC by ZIF-67 could reach 1583.128 mg·g−1 at pH = 5.0, an initial TC concentration of 450 mg·g−1, an adsorption time of 720 min, and a temperature of 308K.The pseudo-second-order kinetic model and Langmuir’s isothermal adsorption model could describe the adsorption process better, which proved that the adsorption of ZIF-67 on TC was mainly monolayer adsorption dominated by chemisorption. Mechanistic studies showed that the adsorption process of ZIF-67 on TC was mainly through electrostatic interactions, pore adsorption, π–π interactions, and framework coordination of ZIF-67 surface cations with TC.