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A series of K2Ca1-xP2O7:xEu3+ phosphors were prepared by a high-temperature solid-state reaction method. The crystal structure was analyzed by X-ray diffraction (XRD). Fluorescence spectra, decay curves, and color coordinates were investigated. Under excitation at 393 nm, the strongest emission peak was located at 590 nm, corresponding to the 5D0→7F1 transition of Eu3+, and the sub-strongest one was located at 612 nm which belongs to the 5D0→7F2 transition of Eu3+. XRD results show that the patterns doped with a small amount of Eu3+ were fitted well with the standard card of K2CaP2O7, while the pattern with the doping of high concentration Eu3+ (heavy-doping) indicated the co-existence of K2CaP2O7 and EuPO4 phase which leads to luminescent intensity of phosphors enhance remarkablely. The concentration quenching mechanism was explained through dipole-dipole interaction. Different doping amounts of Eu3+ and charge compensators will affect the symmetry of the host lattice, thereby affecting the emission intensity ratio of orange and red light. The color coordinates of K2Ca0.49P2O7:0.51Eu3+ and K2Ca0.33P2O7:0.67Eu3+, 0.1Na+ phosphor were near the red region, which was close to commercial red-emitting phosphors Y2O3:Eu3+ and standard red light, respectively. A series of K2CaP2O7 phosphors emitting orange-red light with different concentrations of Eu3+ doping and alkali metal ions co-doping were synthesized via a high-temperature solid-state method, and their structure and luminescent properties were characterized. A new strategy for adjusting the light color parameters of K2CaP2O7 phosphors has been constructed. [ABSTRACT FROM AUTHOR]

Lateral movement of soil organic carbon (SOC) induced by soil erosion and runoff changes spatial distributions of SOC, and further changes the land‐atmosphere CO2 exchange and terrestrial carbon budget. However, current ecosystem models do not or only poorly integrate the process of SOC lateral movement and cannot simulate the impacts of soil erosion on the carbon cycle. This study integrated SOC erosion and deposition processes into a process‐based ecosystem model (i.e., Integrated BIosphere Simulator (IBIS)), and separately simulated the lateral movements of dissolved organic carbon (DOC) and particulate organic carbon (POC). The model was evaluated in three river basins in Northeast China that are dominated by cropland, forest, and grassland. The results showed that the model reproduced well the production, erosion, and deposition of DOC and POC. The annual SOC lateral movement (1.34–7.22 g C m−2 yr−1) induced by erosion in the three tested basins was 0.27%–1.45% of the annual net primary production. The model developed in this study has great implications for simulating the lateral movements of SOC in terrestrial ecosystems, which can improve model performance in projecting the terrestrial carbon budget. Plain Language Summary: Lateral movement of soil organic carbon (SOC) with soil erosion and runoff is an important process in estimating land carbon budget. However, the current ecosystem models are not or poorly integrated this process, and cannot simulate the impacts of lateral movement of SOC on carbon cycle. This study integrates SOC erosion and deposition processes into a process‐based ecosystem model (Integrated BIosphere Simulator (IBIS)), and separately simulates the lateral movements of dissolved organic carbon (DOC) and particulate organic carbon (POC). The model was evaluated at three river basins in Northeast China dominated by cropland, forest and grassland, respectively. The results showed the model can reproduce well the production, erosion, deposition of DOC and POC. The model developed in this study has great implications for simulating the lateral movements of SOC in terrestrial ecosystem, which can improve model performance on projecting terrestrial carbon budget. Key Points: Current ecosystem models inadequately depict the lateral movement of SOC, causing uncertainties in terrestrial carbon cycle modelingWe integrated SOC erosion and deposition into a process‐based ecosystem model and evaluated it in three Chinese river basinsModel simulations well represented observed data for the production, erosion, and deposition of organic carbon [ABSTRACT FROM AUTHOR]