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Warehouse is an important part of the supply chain. However, the frequent failure of warehouse equipment greatly restricts scheduling efficiency. To achieve efficient operation and reduce the frequency of sudden failures, a new strategy for warehouse center maintenance based on the prediction of total amount of stock in & out operations is proposed. The feasibility of this strategy has been proved by using the historical data of operation and maintenance for three auto parts warehouse centers in South China, North China and East China. The orthogonal experimental method, which can select the preferred combination of hyperparameters quickly, is used to implement hyperparameter estimation for the predictive models. Based on the performance of different predictive models on the warehouse operation datasets, we determined the best model to predict the future total amount of warehouse stock in & out operations. The results show that compared with other models, the bidirectional long-short-term memory (Bi-LSTM) model obtains the highest accuracy on the test set, which is used for subsequent prediction. According to the prediction results, there is no need to arrange an overhaul plan for the North China and East China warehouse centers in the short term. However, the South China warehouse center may have frequent equipment failures in two months. It is necessary to formulate corresponding maintenance plans in advance.

A series of layered Mg-Al spinel supported Ce-Fe-Zr-O oxygen carriers were prepared for co-production of syngas and pure hydrogen via chemical looping steam reforming (CLSR). The presence of magnesium-aluminum layered double oxides (MgAl-LDO) significantly increases the specific surface area of the mixed oxides, reduces the particle size of CeO2-based solid solution and promotes the dispersion of free Fe2O3. When reacting with methane, MgAl-LDO supported oxygen carrier shows much lower temperature for methane oxidation than the pure Ce-Fe-Zr-O sample, indicating enhanced low-temperature reactivity. Among different Ce-Fe-Zr-O(x)/MgAl-LDO samples, the Ce-Fe-Zr-O(40 wt%)/MgAl-LDO sample shows the best performance for the selective oxidation of methane to syngas and the H2production by water splitting. After a long period of high temperature redox experiment, the Ce-Fe-Zr-O(40 wt%)/MgAl-LDO oxygen carrier still shows high activity for syngas generation. The comparison on the morphology of the fresh and cycled oxygen carriers indicates that the Mg-Al spinel support still forms a stable skeleton structure with high dispersion of active components on the surface after the long-term cycling, which contributes to excellent redox stability of the Ce-Fe-Zr-O(40 wt%)/MgAl-LDO oxygen carrier.

We propose a plasma chemical looping CO2splitting (PCLCS) approach that enables highly efficient CO2conversion into O2-free CO at mild temperatures. PCLCS achieves an impressive 84% CO2conversion and a 1.3 mmol g–1CO yield, with no O2detected. Crucially, this strategy significantly lowers the temperature required for conventional chemical looping processes from 650 to 1000 °C to only 320 °C, demonstrating a robust synergy between plasma and the Ce0.7Zr0.3O2oxygen carrier (OC). Systematic experiments and density functional theory (DFT) calculations unveil the pivotal role of plasma in activating and partially decomposing CO2, yielding a mixture of CO, O2/O, and electronically/vibrationally excited CO2*. Notably, these excited CO2* species then efficiently decompose over the oxygen vacancies of the OCs, with a substantially reduced activation barrier (0.86 eV) compared to ground-state CO2(1.63 eV), contributing to the synergy. This work offers a promising and energy-efficient pathway for producing O2-free CO from inert CO2through the tailored interplay of plasma and OCs.

The hepatic venous pressure gradient (HVPG) is the gold standard for cirrhotic portal hypertension (PHT), but it is invasive and specialized. Alternative non-invasive techniques are needed to assess the hepatic venous pressure gradient (HVPG). Here, we develop an auto-machine-learning CT radiomics HVPG quantitative model (aHVPG), and then we validate the model in internal and external test datasets by the area under the receiver operating characteristic curves (AUCs) for HVPG stages (≥10, ≥12, ≥16, and ≥20 mm Hg) and compare the model with imaging- and serum-based tools. The final aHVPG model achieves AUCs over 0.80 and outperforms other non-invasive tools for assessing HVPG. The model shows performance improvement in identifying the severity of PHT, which may help non-invasive HVPG primary prophylaxis when transjugular HVPG measurements are not available.

Coke oven gas (COG) is one of the most important by-products in steel industry, and the conversion of COG to value-added products has attracted much attention from both economic and environmental views. In this work, we use the chemical looping reforming technology to produce pure H2from COG. A series of La1-xSrxFeO3(x = 0, 0.2, 0.3, 0.4, 0.5, 0.6) perovskite oxides were prepared as oxygen carriers for this purpose. The reduction behaviors of La1-xSrxFeO3perovskite by different reducing gases (H2, CO, CH4and the mixed gases) are investigated to discuss the competition effect of different components in COG for reacting with the oxygen carriers. The results show that reduction temperatures of H2and CO are much lower than that of CH4, and high temperatures (>800 °C) are requested for selective oxidation of methane to syngas. The co-existence of CO and H2shows weak effect on the equilibrium of methane conversion at high temperatures, but the oxidation of methane to syngas can inhibit the consumption of CO and H2. The doping of suitable amounts of Sr in LaFeO3perovskite (e.g., La0.5Sr0.5FeO3) significantly promotes the activity for selective oxidation of methane to syngas and inhibits the formation of carbon deposition, obtaining both high methane conversion in the COG oxidation step and high hydrogen yield in the water splitting step. The La0.5Sr0.5FeO3shows the highest methane conversion (67.82%), hydrogen yield (3.34 mmol·g−1) and hydrogen purity (99.85%). The hydrogen yield in water splitting step is treble as high as the hydrogen consumption in reduction step. These results reveal that chemical looping reforming of COG to produce pure H2is feasible, and an O2-assistant chemical looping reforming process can further improves the redox stability of oxygen carrier.