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Carbon nanomaterials are widely used in the treatment of water pollutants because of their structural characteristics such as large specific surface area， complex pore structure， and rich surface functional groups. This paper summarized the carbon sources and preparation methods of nanocarbon materials， analyzed the principles and influencing factors of nanostructure regulation of carbon materials， reviewed the research progress in nanocarbon adsorption of toxic pollutants in water， and put forward the bottlenecks that need to be broken through for the future industrial application of nanocarbon materials. Hydrothermal， pyrolysis and chemical vapor deposition are the common methods for the preparation of nanocarbon， and traditional carbon sources， such as sugars， petrochemicals， and biomass， can be used to obtain nanostructured carbon through the modulation of parameters such as preparation temperature and activator. Carbon nanotubes， carbon nanospheres， and nanoporous carbon have been developed for better contact with pollutants， thus exhibiting significant adsorption advantages for toxic pollutants such as phenols， benzenes， dyes， antibiotics， and heavy metal ions. In order to realize the wide application of nanocarbon adsorbent materials， further research is required to be carried out in the future on the development of green and efficient preparation process of nanocarbon， the exploration of the formation and evolution law of carbon structures， the design of macroscopic use scheme of nanocarbon， and the development of nanocarbon based composite materials.

Photocatalytic technology, as one of the most promising environmental remediation tools, has a wide range of applications in the field of removing antibiotic-based pollutants from wastewater. Therefore, to obtain efficient green and inexpensive photocatalysts, a p–n type Bi2MoO6/CuS composite photocatalyst modified by lignin carbon quantum dots (CQDs) was successfully prepared by solvothermal in situ co-precipitation in this study. It was used to achieve efficient photocatalytic degradation of tetracyclic hydrochloride antibiotics (TCH). The composites were systematically characterized by XRD, FTIR, XPS, SEM, TEM, EIS, nitrogen adsorption–desorption test, and UV–Vis DRS regarding crystal structure, microscopic morphology, and photoelectric properties. The results showed that the prepared samples had good crystallinity and high purity. The photocatalytic degradation experiments further demonstrated that the Bi2MoO6/CuS composites modified by CQDs exhibited excellent photocatalytic activity compared to Bi2MoO6 and CuS monomers wherein CQDs@Bi2MoO6/CuS 2 was the most effective, with a TCH removal of 96.98% and a degradation rate constant (K) of 0.04405 min−1 after 60 min of light exposure. The TCH removal could be maintained at 78.25% after four cycles. The ESR and LC–MS experiments demonstrated that h+ and ·O2− were the main active substances for photocatalytic degradation of TCH. This work provides an efficient catalyst for TCH removal and offers new ideas for applying p–n heterojunction composites in photocatalysis. [ABSTRACT FROM AUTHOR]

Zinc (Zn) can improve resistance of rice plants to abiotic stress and promote the recovery of rice tillers by influencing auxin (IAA) synthesis, Zn absorption is closely related to nitrogen (N) concentrations; however, the mechanisms by which Zn regulates rice tiller recovery at low temperatures under different N levels are rarely studied. In this study, a solution culture experiment was conducted at two temperatures, three different Zn concentrations, and two N concentrations. Low temperature during the vegetative stage damaged the rice antioxidant system, suppressed nutrient uptake, and decreased the number of tillers. Increasing Zn application improved the resistance of rice plants to low‐temperature stress under normal N levels, enhanced nutrient absorption, improved tiller bud cytokinin (CTK) concentrations, and the CTK/IAA ratio, which accelerated tiller recovery relative to plants receiving standard Zn treatment. Shoot Zn concentrations were positively correlated with tiller numbers at normal N levels. High N attenuated the positive effect of Zn on rice tillering at low temperatures due to higher shoot Zn and IAA accumulation, and lower tiller buds CTK/IAA ratios. However, appropriate Zn application under high N levels was conducive to breaking tiller dormancy and promoting tillering growth spurts when recovering to normal temperature, which was related to the synergistic regulation of hormone balance and nutrient absorption by N and Zn. In conclusion, Zn could enhance rice low‐temperature stress resilience and facilitate tiller recovery via balancing the hormones in tiller buds. However, higher environmental N limited the stimulation of Zn on rice tillering under low temperature. [ABSTRACT FROM AUTHOR]

To find efficient adsorption material for the treatment of malodorous gas in sewage plants, in this study, pure silicon Mobil composition of matter-41 (MCM-41) with cobblestone morphology, a member of the family of mesoporous molecular sieve, was used. Herein, copper-modified MCM- 41 (Cu-MCM-41) was prepared by hydrothermal method for H2S adsorption. The experimental results showed that when the water-to-silicon ratio (nH2O:nTEOS) was 493:1, stirring time was 15 min, and modification amount of copper reached 30%; the H2S adsorption time on Cu-MCM-41 was close to 90 min and the theoretical sulfur capacity could reach 34 mg g–1, which is much higher than the adsorption performance of pure nano-copper oxide. After copper modification, the specific surface area of the sample decreased, and countless small nano CuO particles could be observed in the cobblestone particles. Moreover, these particles were found to be evenly dispersed on the surface and pores of MCM-41, which facilitated the adsorption reaction with H2S, and improved the utilization rate of the active component nano CuO. The adsorbed H2S mainly existed in the form of CuS, Cu2S, and CuSO4 on the surface of the material, and redox reaction occurred during the adsorption process. This research provides an effective approach for the preparation of new material for the treatment of sulfur-containing malodorous gas. [ABSTRACT FROM AUTHOR]

The sludge from a sewage treatment plant was used as the raw material, the plant ash was used as the activator, urea was used as the modifier and the sludge was used to prepare the sludge carbon material. Orthogonal tests were designed to determine the best preparation conditions for the samples. The structure and deodorization products of sludge carbon were analyzed by SEM, FT-IR, XPS, specific surface area and pore structure analyses. The results showed that the sludge carbon T550U1.5t60SAC had the best deodorization performance when the pyrolysis temperature was 550 °C, the stucco/drug ratio was 1 : 1.5, and the pyrolysis time was 60 min under N2 atmosphere. The penetration time for hydrogen sulfide and methyl mercaptan reached 200 min and 100 min, respectively. Structural analysis showed that the T550U1.5t60SAC carbon material had a rough surface and wide pore diameter distribution. It not only had oxygen-containing functional groups on the surface, but the concentration of the nitrogen-containing functional groups on the surface also increased with the addition of urea, and the surface alkalinity of the material increased. These factors provided channels and activity points for the adsorption of H2S and CH3SH. The surface area and pore size distribution of the adsorbed T550U1.5t60SAC sludge changed significantly, particularly after the micropores disappeared. This indicated that the deodorization reaction mainly occurred in the micropores, and deodorized products such as elemental sulfur and sulfate appeared. The analysis suggested that the ˙OH radical on the surface of sludge carbon was the main species for the oxidation of H2S and CH3SH. [ABSTRACT FROM AUTHOR]

In a series of field studies, differing rainfall patterns within the first month after N fertilizer application to a coarse-textured soil significantly affected yields and N-use efficiency of irrigated corn (Zea mays L.), and responses varied with N source. A laboratory study was conducted to evaluate effects of N source with precipitation following N application to a coarse-textured soil. Nitrogen sources included urea-ammonium nitrate solution (UAN), UAN with additives of either nitrapyrin (2-chloro-6-[trichloromethyl] pyridine) as a nitrification inhibitor or maleic-itaconic acid copolymer as a urease and nitrification inhibitor, or polymer-coated dry urea (PCU). These products were applied to soil in chambers from which ammonia (NH3) volatilization and nitrate (NO3-) leaching were measured over 31 d following fertilization. Precipitation events simulated rainfall frequencies and amounts that occurred in field studies in dry and wet conditions. Ammonia volatilization was lower in wet than dry conditions. Total NH, loss for the dry precipitation regime ranged from 11 to 18% of applied N fertilizer for all treatments except PCU (<1%). In contrast, all treatments in wet conditions had low NH3 loss (<1% of applied N). However, substantial NO3- leaching occurred with wet conditions, comprising 48 to 66% of applied N for most treatments. Leaching loss was the greatest for UAN, followed by UAN with additives. For either dry or wet environments, losses of N from PCU to either NH3, volatilization or NCK3- leaching were negligible. [ABSTRACT FROM AUTHOR]

The present study deals with the synthesis of zeolite-loaded FeOOH@ZnO by hydrothermal method and investigates the effects of coexisting SO 3 2- and PO 4 3- ions in the aqueous solution on the adsorption performance for S 2- . The results showed that the HNO 3 -modified zeolite loaded with FeOOH@ZnO (FeOOH@ZnO/HZ) resulted in a maximum S 2- removal rate of ≈98%. The adsorbent's performance on removing S 2- was significantly enhanced, compared with NaOH and ZnCl 2 -modified zeolites loaded with FeOOH@ZnO, and the adsorption was proved to be a heat-absorbing process. When SO 3 2- and PO 4 3- coexisted with S 2- , SO 3 2- and PO 4 3- had a significant influence on the adsorption properties of FeOOH@ZnO/HZ. When three ions of S 2- , SO 3 2- and PO 4 3- were present simultaneously, the adsorption performance of FeOOH@ZnO/HZ on S 2- was further, and the removal rate dropped to about 80%. Moreover, FeOOH@ZnO/HZ also adsorbed PO 4 3- and SO 3 2- in the system containing multiple ions, but the adsorption rates of PO 4 3- and SO 3 2- were much lower than S 2- . This indicated that the adsorption of S 2- in the presence of FeOOH@ZnO/HZ dominates under competitive conditions.