a b s t r a c tA micrometer-sized, nanostructured, flower-like Co 3 O 4 -CeO 2 composite oxide was synthesized by an ethylene-glycol-mediated process. The composite oxide was an assembly of polycrystalline nanoparticles, with a typical mesoporous structure. The composite's catalytic activity in 1,2,4-trichlorobenzene degradation was evaluated using a pulsed-flow microreactor-gas chromatography system, and compared with that of quartz sand, commercial CeO 2 , commercial Co 3 O 4 , and a Co 3 O 4 /CeO 2 equimass mixture. The composite oxide was a promising catalyst for 1,2,4-trichlorobenzene degradation. This is attributed to the structural features of the composite oxide with a high specific surface area and a high total pore volume, and the synergistic effect between the two composite phases. The easy creation of high-mobility active oxygen on CeO 2 and the easy cleavage of Co O bonds at the interface of the two components promote reactivity of Co 3 O 4 in 1,2,4-trichlorobenzene degradation. Pulsed catalytic theory suggests a first-order reaction between the composite oxide and 1,2,4-trichlorobenzene, with an apparent activation energy of about 27 kJ/mol, and degradation on the Co 3 O 4 -CeO 2 composite oxide would occur easily.

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Relative to the catalyst-free reaction system, the concentration and total toxic equivalent values of 2,3,7,8-PCDFs decreased by 24.1-99.7% and 86-98.4%, respectively, in the NiFe 2 O 4 catalyst system, while initial increases by 744.5% and 426.3%, respectively, followed by reduction up to 81.6% and 90.7%, respectively, were observed in the Fe 2 O 3 catalyst system. Current findings indicate that NiFe 2 O 4 hindered PCDF formation, which was attributed to its chemical structural stability and high activity towards degradation of biphenyl-like constituents in PCBs.

Water storage capacity of forest ecosystems related to water regulation services (WSCFE) refers to the redistribution, reuse, and recycling of precipitation through three vertical layers: canopy (Aydin et al., 2018), litter (Zagyvai-Kiss et al., 2019), and soil (Olarieta et al., 2017). Water regulation, which is related to the hydrological cycle, water flow maintenance, and flood protection, is one of the important ecosystem services (Ouyang et al., 2016). Specifically, the water regulation function includes maintaining humidity in the canopy layer, avoiding direct erosion of soil by precipitation in the litter layer, and regulating flood, runoff and water storage in the soil layer. For example, the North American forest-covered regions (Duan et al., 2016;Hallema et al., 2018) and South American rainforests (Jones et al., 2017) generate and recycle over 50% of water consumed to maintain ecosystem function and integrity, and part of this water is used for evapotranspiration. Although several studies have considered water flux based on water balance (Milly, 1994;Willmott et al., 1985), the spatial pattern of WSCFE and the factors controlling WSCFE have not been fully investigated at the global scale.Due to the high monetary and labor costs required for long-term observations as well as the absence of open observed data (Rodell et al., 2018), WSCFE is difficult to assess using field measurements on a global scale. Some ecosystem service models such as the Integrated Valuation of Ecosystem Services and Trade-offs and Artificial Intelligence for Ecosystem Services models can be used to simulate WSCFE globally; however, the simulation results have not typically been validated on a large scale with observation data. The Gravity Recovery and Climate Experiment (GRACE) mission tracked groundwater depletion, reservoir changes, surface water, and

h i g h l i g h t s• 1% mol Ca species enhanced the activity of Fe 2 O 3 in the degradation of DecaCB.• Dominant Nona-MonoCB isomers were determined during hydrodechlorination reaction.• Thermodynamic and/or steric effects drive conversion.• Steric effect prevented the hydrodechlorination at ortho-positions. a r t i c l e i n f o b s t r a c tDegradation reaction of decachlorobiphenyl (PCB-209) was investigated over the synthesized Ca speciesdoped Fe 2 O 3 at 300°C. The 1%Ca-Fe 2 O 3 exhibited the highest activity among the four catalysts prepared with the pseudo-first order reaction at k obs = 0.103 min −1 . PCB-207, PCB-197, PCB-176, PCB-184, PCB-150, PCB-136, PCB-148, PCB-104, PCB-96, PCB-54, PCB-19, PCB-4 and PCB-1 were identified as the dominant isomers in their respective nonachlorobiphenyl (NonaCB) to monochlorobiphenyl (MonoCB) homologue groups. Analysis of the hydrodechlorination products indicated that dechlorination was much more favored on meta-and para-than on ortho-positions. The formation of significantly predominant NonaCB and octachlorobiphenyl (OctaCB) isomers was attributed to lower energy principles and to the 90°dihe-dral angles of two aromatic rings which prevented the hydrodechlorination at ortho-positions. When the number of chlorine atoms is not more than 7, the steric effect supports the formation of predominant PCB isomers having chlorines at four ortho-positions. During the dechlorination of tetrachlorobiphenyl (TetraCB) formed to generate monochlorobiphenyl (MonoCB) isomers, the chlorine atoms fully substituted at the ortho-positions have to be successively removed, with the first two dechlorinations preferentially occurring at the two different benzene rings. This is dissimilar to that of octachloronaphthalene in which the hydrodechlorination reaction happened preferentially at ortho-position due to the existence of steric effects. The opposite roles of the steric effect in ortho-position between PCB-209 and PCN-75 might be due to the difference of the π -conjugated plane caused by the dihedral angle of 90°and 0°of the two aromatic rings.

BACKGROUND Soy hull, a by‐product of crop processing, is rich in pectin‐like polysaccharides that have potential for thickening, gelling and emulsifying applications. The effect of ammonium oxalate (SHPA) and sodium citrate (SHPS) on the conformation, physicochemical properties and emulsifying ability of soy hull polysaccharide (SHP) were investigated. RESULTS The composition analysis showed that SHPS had more polysaccharide, protein, and higher molecular weight than SHPA. Images of atomic force microscopy (AFM) and scanning electron microscopy (SEM) showed that SHPS molecules appeared spherical bodies with smooth and firm surfaces, while SHPA molecules appeared chain‐like bodies with rough and wrinkled surface. At the oil–water interface, SHPS adsorbed faster and formed a more elastic interfacial layer than SHPA. The characterization of the prepared emulsions showed that the SHPS emulsion was a smaller particle size and more stable system within 30 days than SHPA emulsion, especially at the SHPS concentration of 9 mg mL−1. Images of cryo‐scanning electron microscopy (cryo‐SEM) also demonstrated SHPS formed clearer network structure on the surface of the oil droplets, compared to SHPA. CONCLUSION Overall, ammonium oxalate and sodium citrate significantly influenced the composition and properties of the SHP. SHPS exhibited a better emulsifying ability than SHPA, which was mainly due to the higher protein content of SHPS and the sodium ion (Na+) residue of sodium citrate. This study is useful for the extraction and application of SHP and other plant‐based polysaccharides. © 2023 Society of Chemical Industry.