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The steel industry is considered an important basic sector of the national economy, and its high energy consumption and carbon emissions make it a major contributor to climate change, especially in China. The majority of crude steel in China is produced via the energy- and carbon-intensive blast furnace–basic oxygen furnace (BF–BOF) route, which greatly relies on coking coal. In recent years, China’s steel sector has made significant progress in energy conservation and emission reduction, driven by decarbonization policies and regulations. However, due to the huge output of crude steel, the steel sector still produces 15% of the total national CO2 emissions. The direct reduced iron (DRI) plus scrap–electric arc furnace (EAF) process is currently considered a good alternative to the conventional route as a means of reducing CO2 emissions and the steel industry’s reliance on iron ore and coking coal, since the gas-based DRI plus scrap–EAF route is expected to be more promising than the coal-based one. Unfortunately, almost no DRI is produced in China, seriously restricting the development of the EAF route. Here, we highlight the challenges and pathways of the future development of DRI, with a focus on China. In the short term, replacing natural gas with coke oven gas (COG) and byproduct gas from the integrated refining and chemical sector is a more economically feasible and cleaner way to develop a gas-based route in China. As the energy revolution proceeds, using fossil fuels in combination with carbon capture, utilization, and storage (CCUS) and hydrogen will be a good alternative due to the relatively low cost. In the long term, DRI is expected to be produced using 100% hydrogen from renewable energy. Both the development of deep processing technologies and the invention of a novel binder are required to prepare high-quality pellets for direct reduction (DR), and further research on the one-step gas-based process is necessary.

BackgroundMelanoma, a malignant tumor of the skin, presents challenges in its treatment process involving modalities such as surgery, chemotherapy, and targeted therapy. However, there is a need for an ideal model to assess prognosis and drug sensitivity. Programmed cell death (PCD) modes play a crucial role in tumor progression and has the potential to serve as prognostic and drug sensitivity indicators for melanoma.MethodsWe analyzed 13 PCD modes including apoptosis, necroptosis, ferroptosis, pyroptosis, netotic cell death, entotic cell death, lysosome-dependent cell death, parthanatos, autophagy-dependent cell death, oxeiptosis, disulfidptosis, and alkaliptosis. These modes were used to construct a model that incorporated genes related to these 13 PCD modes to establish a cell death index (CDI) to conduct prognosis analysis. Transcriptomic, genomic, and clinical data were collected from cohorts including TCGA-SKCM, GSE19234, and GSE65904 to validate this model.ResultsA CDI consisting of ten gene signatures was established using machine learning algorithms and divided into two groups based on CDI values. The high CDI group exhibited relatively lower numbers of immune-infiltrating cells and showed resistance to commonly used drugs such as docetaxel and axitinib. Our validation results demonstrated good discrimination in PCA analysis between CDI groups, and melanoma patients with higher CDI values had worse postoperative prognoses (all p < 0.01).ConclusionThe CDI model, incorporating multiple PCD modes, accurately predicts the clinical prognosis and drug sensitivity of melanoma patients.

Abstract Objective To compare the computed tomography (CT) images of patients with locally advanced gastric cancer (GC) before and after neoadjuvant chemotherapy (NAC) in order to identify CT features that could predict pathological response to NAC. Methods We included patients with locally advanced GC who underwent gastrectomy after NAC from September 2016 to September 2021. We retrieved and collected the patients’ clinicopathological characteristics and CT images before and after NAC. We analyzed CT features that could differentiate responders from non-responders and established a logistic regression equation based on these features. Results We included 97 patients (69 [71.1%] men; median [range] age, 60 [26–75] years) in this study, including 66 (68.0%) responders and 31 (32.0%) non-responders. No clinicopathological variable prior to treatment was significantly associated with pathological response. Out of 16 features, three features (ratio of tumor thickness reduction, ratio of reduction of primary tumor attenuation in arterial phase, and ratio of reduction of largest lymph node attenuation in venous phase) on logistic regression analysis were used to establish a regression equation that demonstrated good discrimination performance in predicting pathological response (area under receiver operating characteristic curve 0.955; 95% CI, 0.911–0.998). Conclusion Logistic regression equation based on three CT features can help predict the pathological response of patients with locally advanced GC to NAC.

Abstract The fault of the tie line between the photovoltaic (PV) station and the grid is a serious fault for the PV station. It will cause the PV station to operate into an unintentional island. The uncontrolled Island voltage and frequency will inevitably lead to the disconnection of the inverter in the station. This situation will bring great losses to PV operators and impact to the power grid. In order to deal with the tie line fault, this paper analyzes the operation characteristics of PV stations in case of tie line fault firstly. Then a tie line fault ride‐through method based on cooperative strategy of small capacity energy storage (ES), relay protection and PV inverters is proposed. The islanding switching control strategies of PV and ES are designed respectively. The cooperative strategy of protection, PV controller and ES controller is formulated as well. The real‐time digital simulator (RTDS) closed‐loop test platform including line protection device, ES controller and PV controller is built to verify the effectiveness of the proposed method.

Abstract Background The prognosis of patients with gastric cancer (GC) with gastric outlet obstruction (GOO) after gastrectomy is highly variable. In this study, we aimed to develop a nomogram to predict the prognosis of these patients. Patients and Methods Data from 218 GC patients with GOO who underwent gastrectomy at Sun Yat-sen University Cancer Center were retrospectively collected as a training cohort. The data of 59 patients with the same diagnosis who underwent gastrectomy at the First Affiliated Hospital of Guangxi Medical University were collected as an external verification cohort. A nomogram for the overall survival (OS) was developed using the Cox regression model in the training cohort, which was validated in a verification cohort. Results Multivariate analysis showed that the surgical procedure (P

The high-pure magnetite concentrate (HPMC) was studied for a substitution of iron scale to produce the magnetic powder of strontium hexaferrite via the conventional ceramic process in this work. The magnetic powder obtained under the optimum conditions had a magneto plumbite structure, which was confirmed by X-ray diffraction (XRD). Scanning electron microscope (SEM) depicted that ferrite grains were hexagon shaped and evenly distributed with an average particle size of about 1 μm. Furthermore, a comparison of magnetic powders separately produced with HPMC and iron scale was made by detecting the magnetic properties of their sintered magnets using a permanent magnetic measuring system. The results demonstrated that the HPMC magnetic powder had a superiority over iron scale magnetic powder, and it had fully achieved the level of Y30-1 product in China. In the final part, the economic feasibility of using HPMC for magnetic powder production was verified by the cost–benefit analysis.

BackgroundIn recent five years, reports regarding albumin-to-globulin ratio (AGR) and the survival of gastric cancer (GC) have emerged rapidly, yet their association remains controversial. This meta-analysis was aimed to provide an insight into the prognostic significance of pretreatment AGR in GC.MethodsPubMed, Embase, Cochrane library, Web of Science, WanFang, China National Knowledge Infrastructure (CNKI) and VIP databases were searched for relevant studies, from inception to September 30, 2020. Individual hazard ratios (HRs) with their 95% confidence intervals (CIs) were combined by Stata 12.0 software to evaluate the association between pretreatment AGR and overall survival (OS) and disease-free survival/progression-free survival (DFS/PFS).ResultsA total of 8,305 patients with GC from 12 studies were included for further analysis. Pooled analyses indicated that low AGR was closely associated with worse OS (HR = 1.531, 95% CI: 1.300–1.803, P < 0.001) and worse DFS/PFS (HR = 2.008, 95% CI: 1.162–3.470, P = 0.012) in GC patients. Moreover, subgroup analyses demonstrated that the association between low AGR and worse OS remained constant despite variations in country, tumor stage, cut-off value, cut-off selection and treatment method.ConclusionAGR could act as an efficient prognostic indicator for GC, and that low pretreatment AGR predicts poor prognosis in GC.

With the integration of distributed renewable energy to the distribution network and the development of multiterminal flexible DC transmission technology, multiterminal flexible DC distribution network has broad application prospects. At the same time, with the rapid development of new energy vehicles, the echelon utilization of power battery has become a research hotspot. By analyzing the characteristics of flexible DC distribution network and echelon utilization battery, the structure and control strategy of modular multilevel converter (MMC), DC solid-state transformer, photovoltaic power generation, wind power generation, and echelon utilization battery energy storage system are established, respectively, in this paper. To achieve a DC network connection of various types of power supply and load, this paper proposes a starting method of multiterminal flexible DC distribution network and a cooperative control strategy of the wind-solar-storage system. A six-terminal ring-shape DC distribution network model is built in real-time digital simulation (RTDS) platform. The simulation results show that the modeling methods and control strategies of each component in the real-time simulation model meet the operation requirements of the multiterminal flexible DC distribution network, which provides a reference for the construction and research of the flexible DC distribution network.

In remote areas, large power stations are often installed to supply local loads due to the difficulties of power transmission. However, with the development of renewable energies and poverty alleviation programs, many renewable energy stations have been installed in such areas. This large amount of surplus and fluctuating energy causes a poor voltage quality, and this problem is difficult to solve with traditional methods. Adding transmission lines can be a feasible solution, but the related research is limited. To provide a guideline for this solution, a network optimization algorithm is proposed in this paper. In the process, a sub-grid that is far from the national grid with an imbalanced power supply and demand is connected to the national grid directly to improve the power quality. First, the linear performance index power mileage is defined to facilitate the calculation and help denote the voltage quality. Then, an iterative algorithm is formed to perform the network optimization and automatically choose the number of clusters. A case study of an actual power grid in Chongqing, China, and an IEEE 123-bus case are used to verify our algorithm. The results show there is a great improvement in the voltage profile.

Battery energy storage systems (BESS) have wide applicability for frequency regulation services in power systems, owing to their fast response and flexibility. In this paper, a distributed method for frequency regulation based on the BESS is proposed, where the method includes two layers. The upper layer is a communication network composed of agents, which is used to transmit and process information, whilst the bottom layer comprises the power system with the BESS, which provides a frequency regulation service for the system. Furthermore, a set of fully distributed control laws for the BESS are derived from the proposed distributed method, where economic power dispatch and frequency recovery are simultaneously achieved. Finally, simulations were conducted to evaluate the effectiveness of the proposed method. The results show that the system frequency regulation and economic power dispatch are achieved after considering the limits of the battery state of charge and communication delays.

Transition metal selenides and sulfides have attracted much attention as supercapacitor electrode materials, and reasonable construction and modification strategies can effectively improve their actual energy storage capacity. Herein, a CuCoSe@NiS/NF electrode material was optimized from the two dimensions of the material structure and microstructure using a self-supported bimetallic CuCo-MOF template and surface modification. The in situ growth not only secures the structural integrity of the electrode material but also eliminates the unwanted internal resistance, thereby enhancing the material's conductivity. The distribution of different spaces of the nanosheets greatly increased the specific surface area of the material, which endowed it with sufficient electrochemical active sites, thus obtaining the desired electrochemical performance. The strong electronic interactions between the CuCoSe nanosheets and NiS sheet layers significantly increased the charge transport rate. Consequently, the specific capacitance of the prepared CuCoSe@NiS/NF material reached a satisfactory specific capacitance of 2937.6 F g−1 at 1 A g−1. The assembled asymmetric supercapacitor (ASC) delivers a high energy density of 41.8 W h kg−1 at 800 W kg−1. This work provides insights for the rational construction of sulfur and selenium coexisting composite electrode materials and the optimisation of the electrode structures. [ABSTRACT FROM AUTHOR]

When the energy storage battery (ESB) is introduced into the DC microgrid, the DC microgrid can perform demand side management well. To achieve flexible charge and discharge controls of the ESB, the grid-connected device of the ESB needs to have a bidirectional power transmission control function with constant power. Based on this, this Letter first designs circuit topology of bidirectional boost converter for high-power transmission between the ESB and the DC microgrid. Secondly, the control system based on the staggered timing trigger mechanism is developed, and the working process of the converter in the forward and reverse transmission of power is analysed. Finally, the bidirectional boost converter and its control system are verified by real-time digital simulator platform. Simulation results show that the proposed converter and its control system can realise stable high-power bidirectional transmission between the ESB and the DC microgrid, and achieve accurate tracking of the power reference value. [ABSTRACT FROM AUTHOR]