Ethylene acts as an important hormone to trigger the ripening and senescence of fruits and vegetables (F&V). Thus, it is essential to eliminate trace ethylene and prevent F&V losses effectively. There are several technologies currently applying to control the ethylene concentration in the storage and transportation environment, including adsorption, gene modification, oxidation, etc. These protocols will be compared, and special attention will be paid to the low-temperature catalytic oxidation that has already been applied to practical production in this review. The active sites, supports, and reaction and deactivation mechanism of the catalysts for the low-temperature ethylene oxidation will be discussed and evaluated systematically to provide new insights for the development of effective catalysts, along with the suggestion of some perspectives for future research on this important catalytic system for F&V preservation.

Trace ethylene in storage environment induces softening and ripening of fruits, causing short storage life and food wastes. Adsorption is regarded as a promising technology for the removal of trace...

The effect of oxygen vacancy on the optical properties of porous zirconia (ZrO2) was discussed based on the preparation and optical characterization of this material. The configuration coordinate diagram for a discussion of the optical performances of the ZrO2 system was carefully amended. The samples used in the experiments were prepared by the hydrothermal method. The product possesses a porous structure constructed by amorphous zirconia particles and the specific surface area of the product was 151.9 m 2 •g-1. Deconvolution was used to analyze the photoluminescence (PL) spectra and the results are different in some aspects compared with previous reports. The main PL bands of the as-prepared product were located in the violet to blue region while those of the samples after treatment by H3PO4 red-shifted to the blue-green region. Neither the porous structure nor the existence of phosphor reagents in ZrO2 induced any new PL peaks. The oxygen vacancies in the samples formed a new energy level that trapped electrons to form a color center and then luminescent emissions were induced.

Orderedhexagonalmesoporoussilica(HMS)andAl鄄containinghexagonalsilica(AlSBA)arepre鄄 pareddirectlyfromsepioliteusingleachingandsequenttemplatesynthesis.Thestructure,surfaceacidity, and specificsurfaceareaofmesoporousmaterialsareinvestigatedbymeansofSAXRD,TPD,andBETadsorption methods.MesoporousmaterialswithfeaturesofHMSarepreparedafterthesepioliteistreatedby 5 mol•L-1 HClacidsolutionandthenkeptinNaOHsolutionat120 益 for72h.Theorderedorganizationofmaterials improveswiththeformationoftheAlSBAframeworkwhenmodified鄄sepioliteistreatedwithNaAlO 2 solution. SpecificsurfaceareasofHMSandAlSBAare508 m 2 •g-1 and946 m 2 •g-1 , andtheporesizes are3.4nmand 3.9nm, respectively.NH 3 鄄TPDresultsshowthattwoacidcentersappearonAlSBAandHMSsurfaces,andthe acidityandacidstrengthofacidcentersinAlSBAarestrongerthanthatofcorrespondingacidiccentersinthe HMSmesoporousmaterials.

Single atom catalysts (SACs) have been growing as an emerging “hot” topic in environmental remediation. Their performance can be rationally optimized via modulating spatial coordination configuration and porous structure of SACs, which is still challenging. Herein, a novel Si, N co-coordinated cobalt SACs (p-CoSi1N3@D) with 3D freestanding architecture was tailored via employing natural mineral (diatomite) as Si source and porous template. Theoretical calculations and experimental analysis reveal that Si substitution dramatically decreases electronegativity of CoN4 moieties and thus accelerates interaction and electron transfer between peroxymonosulfate and Co single atom center. Moreover, p-CoSi1N3@D inherits hierarchically porous architecture of diatomite, providing more accessible cobalt sites and open diffusion channels for peroxymonosulfate and contaminants in water treatment applications. Thanks to optimal coordination structure and porous architecture, p-CoSi1N3@D can serve as highly active catalyst toward peroxymonosulfate activation, with a turn-over frequency of 299.8 min− 1 for bisphenol A degradation, surpassing those of catalysts with transition metal SACs or oxides in disclosed literature. This work provides a novel vision for development of SACs towards wastewater reclamation.