Ammonia serves as a pivotal feedstock in industrial sectors, particularly as the core raw material for nitrogen fertilizer production. Concurrently, it has garnered increasing attention as a prospective energy carrier. The conventional Haber-Bosch process for ammonia synthesis exhibits significant drawbacks, including heavy reliance on fossil fuels, coupled with high energy consumption and substantial carbon emissions. Promoting the development of green ammonia synthesis technologies driven by renewable energy under mild conditions holds profound significance for sustainable industrial development. Chemical looping ammonia synthesis (CLAS), as an emerging pathway, decouples the ammonia synthesis reaction to effectively mitigate competitive adsorption between N2 and H2, while enabling atmospheric pressure operation. The H2-based CLAS circumvents the energy-intensive reduction step, with its inherent distributed and modular characteristics making it particularly suitable for integration with renewable energy systems. These attributes have positioned CLAS as a highly promising research direction in the current landscape. This review summarizes recent theoretical and experimental advances in nitrogen carriers (NCs) for CLAS, with a particular focus on the screening of NCs in H2-CLAS processes. The review particularly highlights developments in modification strategies for NCs and the integration of external field-assisted CLAS processes.

Chemical looping ammonia synthesis (CLAS), an emerging green ammonia production technology, demonstrates significant potential in distributed ammonia synthesis. While early transition metal-based nitrogen carriers show promise in CLAS, their practical deployment has been hindered by inherent limitations in lattice nitrogen conversion and unsatisfactory NH3 selectivity. Herein, we design a highly efficient Ni-Mo2N composite nitrogen carrier synthesized via a one-step pyrolysis strategy. The optimized 25 % Ni-Mo2N (molar ratio) system reaches an excellent lattice nitrogen conversion rate of 76 %. Ni-Mo2N had an outstanding initial ammonia production rate of 9,050 mu mol center dot g- 1 center dot h- 1, whereas Mo2N had an initial ammonia production rate of 3040 mu mol center dot g- 1 center dot h- 1. Crucially, the incorporation of Ni effectively suppresses the formation of Mo2C during the pyrolysis process, ensuring the structural stability of the catalyst over 10 consecutive cycles and demonstrating 4.5-fold improvement compared to pristine Mo2N. Theoretical calculations systematically unravel the CLAS reaction pathways occurring on Ni-Mo2N surfaces and also reveal the synergistic interaction between Ni clusters and Mo2N. This work establishes a foundational framework for developing next-generation high-efficiency CLAS systems.

The development of ammonia synthesis technologies that operate under milder conditions than those of the Haber-Bosch process continues to be a central goal for sustainable chemical production. Chemical looping ammonia synthesis technology utilizes nitrogen carriers to decouple the ammonia synthesis process into two or more cyclic steps, enabling ammonia production under ambient pressure. In this work, we investigated Pd-modified Mo2N as a high-performance NC and demonstrate its ability to mediate cyclic ammonia generation via a two-step hydrogenation-nitrogen fixation mechanism at ambient pressure. At 500 degrees C, the Pd/Mo2N catalyst achieved an initial ammonia synthesis rate of 10,829 mu mol & sdot;g-1 & sdot;h-1, representing a 3.5-fold enhancement over the unmodified Mo2N. Material characterization indicated that Pd incorporation weakens the Mo-N bond strength and facilitated the release of lattice nitrogen. Under cyclic operation at 650 degrees C, the Pd/Mo2N NC maintained a stable ammonia production rate averaging 327 mu mol & sdot;g-1 & sdot;h-1. DFT calculations further confirmed that Pd reduces the formation energy of nitrogen vacancies, thereby promoting the regeneration of active sites and enhancing the cyclic nitrogen fixation capacity of the carrier.

The dynamic behavior and particle shape effects in the liquid spray zone were investigated through temperature standard deviation, liquid–solid contact efficiency, and electrical conductivity signals. Results indicate that temperature standard deviation increases with proximity to the nozzle. Elevated atomization gas velocity (UL) reduces droplet diameter and improves their dispersion, which leads to a more uniform temperature distribution and a resulting decrease in standard deviation. The temperature standard deviation is decreased and then increased with the increasing of fluidized gas velocity (Uf). Non-spherical particles had a higher temperature standard deviation than spherical particles. This resulted from particle agglomeration, where lower sphericity led to stronger fluctuations. The liquid–solid contact efficiency is enhanced with the increasing of spouted gas velocity (Us), UL, and Uf all. As the liquid spouted rate (QL) increased, the liquid–solid contact efficiency, determined by particle capture of droplets, first rose and then declined. Non-spherical particles exhibit higher liquid–solid contact efficiency than that of spherical particles due to longer residence times, and larger contact areas with droplets. Droplet fluctuations are intense near the nozzle, resulting in high electrical conductivity signal intensity. Increased Us enhances airflow effects, causing frequent voltage signal fluctuations. Flake-like particles accumulate more droplets due to agglomeration, enabling droplets to reach higher bed positions. These studies provide promising research directions for the development of adsorbent pelletization in CO2 capture.

Addressing such limitations of traditional photocatalysts as poor visible light absorption, substantial electronhole recombination, and inefficient reactive oxygen species (ROS) generation is crucial. In this paper, oxygen vacancies (OVs) rich Bi2MoO6(BMO)/ZnSe S-scheme heterojunction was successfully prepared using a simple and mild solvothermal method. The introduction of OVs effectively shortened the band gap and increased the visible light absorption range. The mechanism of inducing OVs into BMO by adapting the concentration of surfactants was uncovered using both experimental and DFT simulation results. OVs-BMO/ZnSe exhibited an enhanced charge transfer capacity because OVs facilitated the formation of a rapid electron transfer pathway at the heterojunction interface. The synergistic effect of OVs and S-scheme heterojunction could effectively inhibit the recombination of photogenerated carriers. Its degradation efficiency and turnover frequency per wattage of light (TOF/P) reached 92.1 % and 854.98 x 10(-10)(mol.g(-1).J(-1)), respectively, during the low power LED white light-driven photocatalytic degradation of 50mg/L TC. The high value of TOF/P demonstrated its practical application potential in comparison with some other reported photocatalysts. Liquid Chromatography-Mass Spectrometry (LC-MS) characterization and ECOSAR simulation results indicated that OVs promoted the generation of ROS, in which center dot O-2, O-1(2) and h(+) significantly reduced the toxicity of intermediate products.

Chemical looping ammonia synthesis (CLAS) is a method for sustainable ammonia production under low temperatures and atmospheric pressure. The key to CLAS lies in the development of an efficient nitrogen carrier (NC). In this study, a composite NC with excellent ammonia synthesis performance and high cycling stability was investigated for CLAS using Na-modified Mo2N supported on SiO2. The results show that the Na/Mo2N/SiO2 NC achieves an impressive maximum ammonia synthesis rate of 4345 mu mol g- 1 h- 1. The enhanced performance of the Na/Mo2N/SiO2 NC is attributed to the role of Na in accelerating the release rate of lattice nitrogen, whereas SiO2 improves NH3 selectivity. After 9 cycles under ambient pressure, the ammonia synthesis rate of the Na/ Mo2N/SiO2 NC remained stable at approximately 854 mu mol g- 1 h- 1 because Na and SiO2 facilitate the regeneration of Mo2N. Furthermore, SiO2 minimises the loss of the active component Na, thereby enhancing cycling stability. This study provides valuable insights into future research on NCs.

Spinel-structured catalysts, with flexible frameworks and adjustable compositions, enhance catalytic performance by creating active sites. During CO2 hydrogenation, these catalysts promote CO2 bond cleavage and activation. This paper investigates the performance of the spinel-type catalyst Na/CaFe2O4, achieving a 39.29 % selectivity for light olefins and a conversion rate of 49.72 %. Data analysis showed that adding Ca increased the concentration of strong basic sites and oxygen vacancies in the catalysts, enhancing CO2 conversion. Additionally, Na and Ca facilitated the dissociative adsorption of C-O bonds and subsequent C-C coupling, improving the catalytic efficiency of CO2 hydrogenation. The catalyst demonstrated exceptional stability over 72 h, suggesting its promising industrial applicability.

This study aims to improve the slow-release performance of a film material for a controlled-release fertilizer (CRF) while enhancing its biodegradability. A water-based biodegradable polymer material doped with biochar (BC) was prepared from modified polyvinyl alcohol (PVA) with polyvinylpyrrolidone (PVP) and chitosan (CTS), hereinafter referred to as PVA/PVP–CTSaBCb. An environmentally friendly novel controlled-release phosphate fertilizer (CRPF) was developed using PVA/PVP-CTS8%BC7% as the film. The effect of the PVA/PVP-CTS8%BC7% coating on the service life of the CRPF was investigated. The film was characterized via stress–strain testing, SEM, FTIR, XRD, and TGA analyses. The addition of the CTS modifier increased the stress of PVA/PVP-CTS8% by 7.6% compared with that of PVA/PVP owing to the decrease in the crystallinity of PVP/PVP-CTS8%. The hydrophilic –OH groups were reduced due to the mixing of CTS and PVA/PVP. Meanwhile, the water resistance of the PVA/PVP-CTS8%BC7% was improved. And the controlled-release service life of the CRPF was prolonged. Moreover, the addition of BC increased the crystallinity of the PVA/PVP-CTS8% by 10%, reduced the fracture elongation of the material, and further improved the biodegradability of the PVA/PVP-CTS8%BC7%. When the amount of BC added was 7%, the phosphorus release rate of the CRPF was 30% on the 28th day. Moreover, the degradation rate of the PVA/PVP-CTS8%BC7% polymer film was 35% after 120 days. This study provides basic data for applying water-based degradable polymer materials in CRFs.

The effects of large granular slow-controlled release fertiliser prepared by a double coating of sulfur and sodium alginate on peanut growth, nitrogen fertiliser utilisation, and soil microbial community were investigated through peanut pot experiments, with a view to providing a theoretical and practical basis for the development of large granular slow-controlled release fertiliser. The results showed that the homemade large granular fertiliser could promote the root development of peanuts, and the root volume increased by 45.10% compared with the uncoated fertiliser at the fruiting stage. At the same time, the soil NH4+-N and NO3--N content were reduced at the seedling stage and increased at the fruiting stage to achieve the fertiliser's slow and controlled release effect. A significant contribution to the net photosynthetic rate was made for growth development and yield in the middle and late stages. Pod dry weight was significantly higher at the blooming stage than uncoated fertiliser, 4.8% higher at the fruiting stage, and 22.9% higher in nitrogen use efficiency (NUE). In terms of microbial bacterial communities, the large granular slow-release fertiliser promoted the diversity of the treated bacterial communities to some extent, with little difference in the relative abundance of soil bacterial communities. These results showed that a one-time application of homemade large granular slow-release fertiliser positively affected peanuts in terms of yield increase, promotion of nitrogen uptake and improved nitrogen utilisation under nitrogen application with urea equivalent, but the overall effect on soil microbial community was small.

Biochar plays an important role in agricultural production as it can improve soil fertility, promote nutrient adsorption and enhance plant growth. However, the distribution of biochar in the soil significantly impacts its application effect. In order to investigate the impact of non-uniform biochar distribution on soil nutrient uptake, root shape, peanut development, and the makeup of soil microbial communities, we carried out greenhouse peanut pot studies. This experiment followed a completely randomised design with four treatments, each with three replications. The four treatments were as follows: no biochar application (B0); concentrated biochar application near seeds (B1); relatively concentrated surface application of biochar (B2), and uniformly dispersed application of biochar (B3). The findings demonstrated that, compared to the no-biochar scenario, the aboveground and root nitrogen uptake was significantly (P < 0.05) improved by the B2 treatment, increasing by 42.79% and 51.39%, respectively, compared to the control group. Additionally, it reduced the concentrations of NO3--N and NH4+-N in the soil. The B2 treatment also significantly (P < 0.05) increased the net photosynthetic rate and aboveground dry matter weight, increasing by 196.85% and 53.96%, respectively, compared to the B0 treatment. The B1 and B3 treatments also demonstrated a higher promoting effect. The growth of the root system and the quantity of root nodules were promoted by the addition of biochar. The number of root nodules in the B2 treatment was 72.22% higher than that in the control group. In terms of microbial and bacterial communities, the addition of biochar increased the number of nitrogen-fixing bacteria to a certain extent, while the relative abundance of soil bacterial communities showed no significant differences. In general, the non-uniform distribution of biochar in the soil significantly affected peanuts' vegetative growth and developmental effects. The relatively concentrated surface application of biochar treatments contributes to improving plant nutrient uptake and root system development. This provides a more effective application method for agricultural personnel to apply biochar fertiliser in the future.

Effect of co-doping of Ca and K in Ca 2− x K x Fe 2 O 5 catalysts on CO 2 hydrogenation performance.

Different catalytic effects were achieved by adjusting different Mn contents in CuO/MnCeO x catalysts.

The chemical looping oxidative dehydrogenation of propane to propylene (CL-ODHP) replaces molecular oxygen with lattice oxygen (Olatt) in oxygen carriers. This method boosts propylene selectivity by avoiding the deep oxidation of propane. Herein, a series of 10V-XCe/Al oxygen carriers with different Ce contents were prepared to realize different VOx-CeOy interactions. The effect of the Ce content in 10V-XCe/Al oxygen carriers on the CL-ODHP reaction was studied and the optimal Ce content was determined. CeO2 prevents the outward diffusion and evolution of Olatt in VOx carriers to the adsorbed electrophilic oxygen species (Oelec), effectively inhibiting the loss of Olatt, improving the selectivity of propylene, and extending the lifetime and activity of the oxygen carriers. After characterizing and analyzing the oxygen carriers, it was found that 10V-3Ce/Al has the highest specific surface area, highest oxygen capacity, and lowest reducibility. The 10V-3Ce/Al also delivers the highest oxidative dehydrogenation performance. At 550 °C, the average propylene and COx selectivity values of 10V-3Ce/Al were 81.87% and 7.28%, respectively (vs. 62.79% and 25.64% respectively, for 10V/Al). It is demonstrated that 10V-3Ce/Al exhibits good cycle stability with no significant decrease in catalytic performance after 15 cycles. In situ diffuse-reflectance infrared Fourier-transform spectroscopy indicates that CL-ODHP on 10V-3Ce/Al undergoes the Mars-van Krevelen mechanism. The migration and evolution of Olatt in oxygen carriers is controlled by reasonably modifying the metal oxide interactions to improve propylene yield. This work will thus guide the subsequent development of novel and efficient CL-ODHP oxygen carriers.

The activity of CO2 methanolization depends on the realization of metal-oxide interactions with different strengths. The CuO/La0.25CeOx catalyst (La content: 25%) demonstrated superior catalytic activity under the reaction conditions of 260 degrees C, with a methanol space-time yield (STY) of 0.281 g(CH3OH)center dot g(cat)(-1)h(-1) and a methanol selectivity of 83.3%. This study elucidates the correlation of the metal-support interactions in CuO/LaCeOx catalysts and the promotion of catalytic activity, which mainly shows that the introduction of La leads to enhanced conversion of Ce4+ into Ce3+ in the catalyst, facilitates oxygen vacancy generation, and activates the formate reaction pathway of CO2 hydrogenation. Thus, this study has considerable significance for the progress of efficient and new catalysts for CO2 methanolization.

Controlling the metal-support interaction is vital for constructing a highly efficient catalytic system. In this work, different Cu–CeOx interactions are realized by preparing a series of CuO/MnCeOx catalysts with varying contents of Mn. The effect of Mn content on the performance of CuO/MnCeOx catalysts for CO2 hydrogenation to CH3OH is analyzed, and the optimum Mn content is determined. The catalyst with 20% Mn content (CuO/Mn0.2CeOx) exhibits the best catalytic performance with a methanol space–time yield of 0.25 gCH3OH·gcat−1h−1 at 260°C. According to X-ray diffractometry, temperature-programmed H2 reduction, temperature-programmed desorption of adsorbed CO2, X-ray photoelectron spectroscopy, and Raman spectroscopy evidence, CuO/Mn0.2CeOx displays the highest catalytic activity because it has the highest content of Cu0 and oxygen vacancies, and medium-to-strong basic sites, which are generated by the strongest metal-support interactions between CuO and MnCeOx solid solution. Insitu diffuse reflectance infrared Fourier-transform spectroscopy evidence indicates that CO2 hydrogenation to methanol over CuO/MnCeOx catalysts proceeds via the formate mechanism. The results in this work are of high significance for controlling the surface basic sites and the oxygen vacancies by rationally altering the metal-support interaction to develop new highly efficient CO2 hydrogenation catalysts.

在农业生态系统中,提高作物对磷的吸收和利用效率是促进作物生长和节约养分资源的关键.为探究不同耕作措施下花生磷吸收效率及土壤盈余磷分布,在胶东半岛的莱西望城、招远夏甸和招远齐山三个试验点开展免耕、浅耕、深耕和深松四种土壤耕作措施下花生生产试验.结果表明,与免耕相比,深耕和浅耕提高了花生产量、磷吸收和磷利用效率.相同磷肥用量下,随着单产每增加 1000 kg/hm2,磷吸收量、磷肥回收率、磷肥偏生产力、磷肥耕作效率分别提高 4.30 kg/kg、0.09 kg/kg、20.40 kg/kg和 0.20 kg/kg,花生产量的提高和磷的吸收呈显著正相关.不同团聚体大小有效磷含量与土壤微生物组成有关,在大于 2000 μm团聚体中有效磷含量随丛枝菌根真菌和腐生真菌的增加而增加,在 53～250 μm团聚体中细菌所占比例与团聚体有效磷含量呈显著正相关,在 250～2000 μm团聚体中放线菌微生物种群占比与有效磷含量呈极显著正相关.上述研究表明,深耕和浅耕是改善花生田植株生长和磷吸收的较优耕作方式.

Peanuts (Arachis hypogaea L.) is an important oil and nitrogen (N) fixing crop. Urease inhibitors (UIs) and nitrification inhibitors (Nis) can mitigate the release of N and reduce the harmful effects of excessive N concentrations. However, the effect of these inhibitors on the soil nutrient-microbial activity-plant growth system is unknown in peanut. The purpose of this study was to investigate the effects and mechanism of N-(n-butyl) thiophosphoric triamide (NBPT), 3,4-dimethylpyrazole phosphate (DMPP) and sulfur-coated urea (SCU) on peanut. The results showed that comparing with urea alone, adding NBPT + DMPP inhibited the urea hydrolysis better and decreased the concentration of NH4+-N + NO3--N by 20.8% in soil. Therefore, it increased the net photosynthetic rate, promoted the development of roots even the absorption of N by peanut, with N use efficiency (NUE) up to 20.8%. The effect of NBPT + DMPP on microorganism was better than that of NBPT alone, which considerably impacted the structure and abundances of aonia oxidizing bacteria (AOB) but not ammonia-oxidizing archaea (AOA). Specifically, g_Nitrosospira and g_Nitrosomonas decreased by 46.9% and 2.2% respectively, and g(c) Betaproteobacteria increased. Furthermore, when combined with SCU on this basis, the overall effect was clearer.

The catalysts were prepared by supporting cobalt ferrite (CoxFe3−xO4) on the surfaces of sphere mesoporous silica (MCM−41) nanoparticles. The electro-assisted catalytic oxidation of MgSO3 displayed an improved oxidation rate under moderate temperatures. Electric field and CoFe2O4/MCM−41 exhibited a beneficial synergistic effect because the associated MgSO3 oxidation rate is 3.38 times the oxidation rate when only the electric field was present, and 1.83 times the oxidation rate when only the catalyst was present. The cyclic voltammetry results proved that the catalysts reduced the oxidation potential of SO32− in the presence of an electric field, and increased the electron transfer rate in the oxidation. Both the X-ray photoelectron spectroscopy (XPS) characterization and free radical scavenging experiment results indicated that Co2+ served as the initiator in the generation of superoxide ions (O2−·), which was the primary active free radical responsible for the oxidation of SO32−. The electron spin resonance (ESR) spectra showed that the electric field and high current density expedited the production of O2−·. The XPS results convincingly demonstrated that the electric field effectively alleviated the catalyst deterioration, and, as a result, significantly improved the catalyst's recyclability. Lastly, the synergistic mechanism between the electric field and the catalyst in the catalytic oxidation of MgSO3 was explored.

Mixtures of shell-biochar and calcium silicate slag were firstly impregnated with pentaethylenehexamine, and then were mixed with wet flue gas desulfurization gypsum (FGDG) particles to prepare the adsorbents. The results showed that the crystalline water in FGDG slags changed the CO2 adsorption mechanisms of the amine groups, and the FGDG modified adsorbents exhibited a comparable cyclic recyclability and the adsorption capacity only decreased by 3.61% up to 12 adsorption/desorption cycles.