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The tomato variety 'Micro Tom' is used as an experimental material in a fully artificial light-type plant factory. An LED light with adjustable illumination modes was used as the light source and a pure white LED light was used as the control. Different illumination mode, such as pure red light, pure blue light, mixed red and blue light, and alternating red and blue light were used as supplementary light. The influence of different red and blue supplemental lighting modes on the growth, development, and fluorescence characteristics of greenhouse tomatoes was explored. The results showed that: (1) in all treatments, the growth indicators and fruit weight of the tomato plants increased to a certain extent. The dynamic change of chlorophyll fluorescence was significantly affected by supplementary light. Pure red light supplementation had the greatest effect on the increase in plant height, stem thickness, leaf area, and yield of the tomato plants. Alternating red and blue light supplementation at intervals of 1h or 6h significantly promoted the increase in chlorophyll content and the improvement of PSII photosynthetic performance. (2) During the vegetative growth stage of tomatoes, under pure red light supplementation, the relative growth rate and absolute growth rate of plant height increased by 106.8% and 60% respectively compared to the control. The relative growth rate and absolute growth rate of stem thickness increased by 50% and 80% respectively. 44 days after sowing, the leaf area of the tomato plants under pure red light supplementation increased by 92.1% compared to the control.(3) During the reproductive growth period of tomatoes, compared with the control, 83 days after sowing, the number of fruits set under pure red light supplementation increased by 73.6%. The horizontal and vertical diameters and volume of tomato fruit increased by 34.4%, 35.3%, and 129.6% respectively.(4) Compared with the control, 44 days after sowing, the chlorophyll content in tomato leaves under alternating red and blue light supplementation at intervals of 1h or 6h increased by 30.3% and 31.8% respectively. 83 days after sowing, the performance index (PIABS) of tomato plants after alternating red and blue light supplementation at intervals of 1h or 6h increased by 100% and 30% respectively compared to the control. The electron transfer efficiency (ETo/CS) of PSII after alternating red and blue light supplementation at intervals of 1h or 6h increased by 16% and 23% respectively compared to the control. In summary, pure red light supplementation can effectively promote the growth and development of facility tomatoes. Alternating red and blue light supplementation at intervals of 1h or 6h significantly affects the fluorescence characteristics of tomatoes. In the future, the most suitable supplementary lighting mode can be chosen based on different production objectives. [ABSTRACT FROM AUTHOR]

A Zn-MOF modified by silver nanoparticles (Ag@1) was synthesized by deposition reduction method. Ag@1 can serve as multi-response fluorescence sensor to detect pesticides, Trp and EDA, showing excellent sensitivity and selectivity. In particular, Ag@1 showed "turn-off" fluorescence sensing for FLU and EDA, and "turn-on" fluorescence sensing for EMB and Trp. It is also effective in detecting pesticides in simulated water and amino acids in fresh fetal bovine serum. In addition, due to its good photocatalytic activity, it can effectively degrade MB. [Display omitted] • Ag@1 was synthesized by deposition of silver nanoparticles on Zn-MOF surface. • Ag@1 showed "turn-off" fluorescence sensing for FLU and EDA. • Ag@1 showed "turn-on" fluorescence sensing for EMB and Trp. • It can effectively detect pesticides in water samples and Trp in fetal bovine serum. • Ag@1 can be used as a photocatalyst to effectively degrade the MB in water. The abuse of pesticides, antibiotics, organic solvents, etc., not only deteriorates the ecological environment, but even affects the normal development of organisms, posing a serious threat to global public health. Efficient and sensitive detection of pesticides, antibiotics, organic solvents and so on are very important, but also a challenge to scientists. By depositing Ag nanoparticles on the surface of Zn-MOF (1 : {[Zn 2 (bta)(bpy)(H 2 O) 2 ]·2H 2 O} n), a new type of composite material (Ag@ 1) was successfully synthesized and analyzed by TEM, EDS, XPS, XRD, IR and other characterization methods. Ag@ 1 can serve as multi-response fluorescence sensor to detect pesticides (fluazinam (FLU) and emamectin benzoate (EMB)), Tryptophan (Trp) and Ethylenediamine (EDA). In particular, Ag@1 showed "turn-off" fluorescence sensing for FLU and EDA, and "turn-on" fluorescence sensing for EMB and Trp. It is worth mentioning that we further explored its analysis of FLU and Trp in real water samples and fetal bovine serum. The recoveries are satisfactory, 97.95 % − 102.39 % and 96.69 % − 101.85 %, respectively. In addition, the photocatalytic performance of Ag@ 1 was found to be excellent, the degradation rate of methylene blue (MB) reached 86 %, and its degradation mechanism was discussed. [ABSTRACT FROM AUTHOR]

Two europium-postdoped metal organic frameworks (MOFs) Eu3+@1 and Eu3+@2 [ 1 :{[Zn 2 (bta)(bpy)(H 2 O) 2 ]·2H 2 O} n , 2 :{[Ni(bta)(bpy)(H 2 O) 2 ][Ni(bpy)·(H 2 O) 4 ]·4H 2 O} n (H 4 bta = 1, 2, 3, 5-benzenetetracarboxylic acid, bpy = 4, 4′-dipyridine)] were prepared by hydrothermal synthesis and post-synthesis modification. MOFs 1 – 2 are all three-dimensional network structure connected by (bta)4- and bpy ligands. Eu3+@ 1 and Eu3+@ 2 in aqueous solution can achieve the quantitative detection of 2, 4, 6-trinitrobenzene (TNP), tetracycline (TC) and pesticides with high sensitivity and selectivity. In particular, when the volume of TNP increases to 50 μL, the luminescence quenching rate of Eu3+@ 2 can reach 99.7% and the LOD for TNP can reach 78 nM. Interestingly, Eu3+@1 has a good response to PTH (Pyrimethanil), while Eu3+@ 2 has a good selectivity to FLU (Fluazinam), and both can be used for rapid in-situ imaging detection of simulated pesticide residues on fresh vegetables. Under UV lamp, Eu3+@ 1 showed a significant fluorescence quenching effect on PTH in beans, while the fluorescence quenching effect of Eu3+@ 2 on FLU on cabbage was obvious. Surprisingly, two kinds of composite materials can be used as anti-counterfeiting ink functional material with strong anti-counterfeiting ability and long term stability. Two kinds of fluorescence sensors (Eu3+@ 1 and Eu3+@ 2) were synthesized by post-synthetic modification method. The sensor not only has high sensitivity, selectivity, stability and anti-interference ability to TNP, TC, PTH/FLU, but also can effectively detect pesticides on vegetables. It is particularly meaningful that they can be used as anti-counterfeiting ink. [Display omitted] • Two Eu-postdoped MOFs Eu3+@ 1 and Eu3+@ 2 were obtained by post-synthesis. • Eu3+@ 1 and Eu3+@ 2 sensors can achieve the quantitative detection of TNP, TC and pesticides with high sensitivity and selectivity. • Eu3+@ 1 has a good response to PTH, while Eu3+@ 2 has a good selectivity to FLU. • Eu3+@ 1 and Eu3+@ 2 have significant fluorescence quenching effect on PTH in bean and FLU in cabbage, respectively. • They can be used as anti-counterfeiting ink with strong anti-counterfeiting ability and long term stability. [ABSTRACT FROM AUTHOR]

• Two new types of Zn-MOF { [Zn(CIA2−)(4,4′-BB)]·0·75H 2 O} n and Co-MOF [Co(CIA2−)(4,4′-BB)·H 2 O] n were synthesized by solvothermal method. • Zn-MOF sensor can achieve the quantitative detection of His, TC, NB and PTH with high sensitivity and selectivity. • Co-MOF can be used as a photocatalyst to photo-catalyze the basic fuchsin and methylene blue dyes. In this paper, two metal-organic frameworks { [Zn(CIA)(4,4′-BB)]·0·75H 2 O} n (1) and [Co(CIA)(4,4′-BB)·H 2 O] n (2) were synthesized by using ligands 5-methoxyisophthalic acid (5-H 2 CIA) and 4,4′-bis((1 H -imidazol-1-yl)methyl)-1,1′-biphenyl (4,4′-BB) under solvothermal conditions. The structures were characterized by TG, IR, PXRD, BET, single-crystal X-ray diffraction and elemental analysis. The results show that 1 and 2 form a three-dimensional structure, where 1 and 2 have good thermal stability. Further study reveals that 1 shows good fluorescence properties and can be used as a fluorescence sensor to detect histidine (His), nitrobenzene (NB), tetracycline (TC) and pyrimethanil (PTH) in water. (LOD: His 0.23 μM, TC 0.17 μM, PTH 0.08 μM, NB 0.03 μM). However, 2 shows better photocatalytic activity and can be used to degrade dyes in water, such as BF (basic fuchsin) and MB (methylene blue). Under visible light irradiation, the degradation rate of BF is 95.5 % and that of MB is 76.1 %. Finally, the mechanism of detection of 1 as a fluorescence probe and the mechanism of photocatalytic degradation of 2 are discussed. Zn-MOF (1) fluorescence sensor was synthesized by hydrothermal method using carboxylic acid and imidazole. The 1 as a fluorescent probe has high sensitivity, selectivity, anti-interference and circulation ability for His-TC PTH and NB. Co-MOF (2) was synthesized by the same method. It is found that 2 can be used as photocatalyst for degradation of BF and MB dyes under visible light. Finally, the detection mechanism of 1 and the degradation mechanism of 2 were discussed. [Display omitted] [ABSTRACT FROM AUTHOR]