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High-strength aluminum alloys have been widely used in aviation， aerospace and other industries because of their high specific strength and good machining property. Corrosion is an important factor affecting the safety and stability of high-strength aluminum alloys in service. Based on the preparation process of high-strength aluminum alloys， this paper focuses on the effect of structural evolution caused by heat treatment on the corrosion property of high-strength aluminum alloys. The corresponding relationship between the microstructure and corrosion behavior of high-strength aluminum alloys is analyzed. Research directions for improving the corrosion property of high-strength aluminum alloys are proposed. The segregation of elements and phases in high-strength aluminum alloys can easily lead to electrochemical inhomogeneity of microstructure， causing corrosion of substrate. Therefore， based on the optimization of composition， the melt casting process， deformation process and heat treatment process of high-strength aluminum alloys should be regulated to prepare the microstructure with uniform distribution of elements and second phases， and uniform electrochemical property， which is crucial for improving the corrosion property of high-strength aluminum alloys. In addition， the corrosion sensitivity of alloys is affected by the width of the precipitate free zone and the distance and distribution of the grain boundary precipitation phases of alloy. Thoroughly studying and clarifying the effect of various structures such as precipitate free zone on the corrosion behavior of alloys is the prerequisite for the preparation of high-strength aluminum alloys with high corrosion property. To balance the mechanical property and corrosion property of high-strength aluminum alloys， heat treatment methods such as aging and thermomechanical treatment should be optimized， and new composite heat treatment methods should be developed. Meanwhile， the test methods and evaluation methods for the corrosion property of high-strength aluminum alloys are discussed. In order to more efficiently and accurately evaluate the corrosion property and service safety of high-strength aluminum alloys， further research work should be carried out in the combined use of traditional evaluation methods with modern data processing technologies such as digital twin， virtual simulation and machine learning.

Summary: Background: Since 1992, when recombinant hepatitis B vaccine was introduced in China, government health officials have used nationally representative serological surveys to monitor progress in prevention and control of hepatitis B. In 2020, we conducted the fourth seroepidemiological survey, which for the first time included medical evaluation of the clinical status of HBsAg positive subjects over the age of 15 and their medical management. We report survey results in comparison with the three previous surveys. Methods: Consistent with previous national surveys, the 2020 survey used a stratified, three-stage cluster random sampling method to select for evaluation 1-69-year-olds in 120 national disease surveillance points. Blood samples were tested for HBsAg, anti-HBV surface antigen (anti-HBs), and anti-HBV core antigen (anti-HBc) in the National Hepatitis Laboratory of the Institute for Viral Disease Control and Prevention of China CDC. HBsAg positive subjects aged ≥15-year were evaluated for evidence of liver disease, and through face-to-face questionnaire-based survey, we determined the healthcare management cascade of HBV-infected individuals. Findings: HBsAg prevalence in 1–69-year-olds was 5.86%; in children 1–4 years of age, seroprevalence was 0.30%; 75 million people were living with HBV nationwide. Among HBsAg-positive individuals 15 years and older, expert medical examination found that 78.03% were HBsAg carriers with no evidence of liver damage, 19.63% had chronic HBV with liver enzyme abnormalities, 0.84% had evidence of cirrhosis, and 0.15% had evidence of liver cancer. 59.78% of HBsAg + individuals were aware that they were positive before the survey, 30 million were unaware; 38.25% of those who knew they were positive (17 million) had medical indications for antiviral treatment, and 17.33% of these individuals (3 million) were being treated with antivirals. Interpretation: The decline in HBsAg prevalence in the general population, from 9.72% in 1992 to 5.86% in 2020, and in 1–4-year-olds from 9.67% in 1992 to 0.30% in 2020, shows progress that continues on track toward WHO targets for prevention of new infections. Implementation of acceptable strategies to identify infected individuals and offer long-term medical monitoring and management will be important to prevent complications from hepatitis B infection and for meeting WHO cascade-of-care targets. Funding: The study was funded by the Major Science and Technology Special Project of China’s 13th 5-Year Plan (grant no. 2017ZX10105015); Central finance-operation of public health emergency response mechanism of Chinese Center for Disease Control and Prevention (131031001000200001, 102393220020010000017).

10Cr13Co13Mo5Ni3W1VE (S280) martensitic ultra-high-strength stainless steel under aging at 200, 400, and 500 ℃ was used as the research object. Through XRD, TEM, EBSD and other test methods, combined with electrochemical test methods and X-ray photoelectron spectroscopy (XPS) tests, the microstructure evolution of S280 and the structural composition and corrosion resistance of the passivation film were analyzed. The relationship between the stability characteristics of the passivation film and the microstructure of the material was studied.The results show that S280 steel aged at 500 ℃ has fine and dispersed precipitates with rich Cr and Mo elements distributed in martensite laths. As the aging temperature increases, there is no obvious precipitation of retained austenite and reverse transformed austenite.At the potential (0.1-0.85 V) of forming a passivation film, the S280 passivation film is a p-type semiconductor in a pH=8.5 borate buffer solution, having a double-layer film structure.The outer layer is composed of loose and porous Fe/Cr hydroxide, and the inner layer is composed of dense Cr/Fe oxide whose composition is mainly Cr2O3.The electrochemical impedance test combined with Mott-Schottky analysis proves that S280 steel aged at 200 ℃ has the best corrosion resistance. Its corrosion resistance is affected by the grain boundary characteristics and the element segregation caused by the precipitated phase.

Wheat pests and diseases are one of the main factors affecting wheat yield. According to the characteristics of four common pests and diseases, an identification method based on improved convolution neural network is proposed. VGGNet16 is selected as the basic network model, but the problem of small dataset size is common in specific fields such as smart agriculture, which limits the research and application of artificial intelligence methods based on deep learning technology in the field. Data expansion and transfer learning technology are introduced to improve the training mode, and then attention mechanism is introduced for further improvement. The experimental results show that the transfer learning scheme of fine-tuning source model is better than that of freezing source model, and the VGGNet16 based on fine-tuning all layers has the best recognition effect, with an accuracy of 96.02%. The CBAM-VGGNet16 and NLCBAM-VGGNet16 models are designed and implemented. The experimental results show that the recognition accuracy of the test set of CBAM-VGGNet16 and NLCBAM-VGGNet16 is higher than that of VGGNet16. The recognition accuracy of CBAM-VGGNet16 and NLCBAM-VGGNet16 is 96.60 and 97.57%, respectively, achieving high precision recognition of common pests and diseases of winter wheat.

In the context of accelerated industrialization and urbanization, the importance of the green energy sector has become increasingly prominent. From the perspective of the role of the financial system, this article deeply explores the role mechanism and environmental constraint relationship of financial instruments in green energy development. The article constructs a measurement model of financial instruments on the efficiency of green energy development, introduces data spatial correlation into the econometric analysis framework, and establishes a spatial econometric model to analyze the impact of financial instruments on development efficiency. By testing the data from 2008 to 2020, the study shows that the level of global financial means support passes the significance level, and the magnitude of the mediating effect when the spatial Durbin model is simplified to an error model is about 13.5%. The study also found that enhancing green energy development can positively affect neighboring regions. This paper provides an effective methodological path for studying the role of financial instruments in green energy development, which is of great theoretical and practical significance for promoting the development of the green energy sector.

The structure of energy consumption and reducing the carbon footprint has become an important issue in the field of carbon and energy conservation. This paper adopts spatial econometric Analysis to construct a framework for analyzing the influencing factors of carbon emissions based on the STIRPAT model. It applies the K-means algorithm to effectively cluster and classify the energy consumption of different regions. Then, the article analyzed these clustering results in depth using the Kaya constant equation to calculate the carbon emissions of each area. The results of the carbon footprint analysis reveal that the Gini coefficient of carbon emissions in the eastern region peaked at 0.352 in 2014, while decreasing to a low of 0.284 in 2019. the western and central areas have the highest Gini coefficients of carbon emissions at 0.271 and 0.248, respectively. furthermore, from 2015 to 2022, the ecological pressure on the carbon footprint of the whole industry has always remained at 3.033 above, reaching a historical high of 3.433 in 2022.The application of this paper not only helps to solve the problems in the existing carbon footprint evaluation methods, but also provides a scientific basis for more effective management and reduction of carbon emission.

Insulin-like-growth factor-1 (IGF-1) is the ligand for insulin-like growth factor-1 receptor (IGF-1R), and the roles of IGF-1/IGF-1R in diabetic nephropathy (DN) are well-characterized previously. However, the biological functions of AG1024 (an IGF-1R inhibitor) in DN remain unknown. This study investigates the roles and related mechanisms of AG-1024 in DN. The experimental DN was established via intraperitoneal injection of streptozotocin, and STZ-induced diabetic rats were treated with AG1024 (20 mg/kg/day) for 8 weeks. The 24 h proteinuria, blood glucose level, serum creatinine, and blood urea nitrogen were measured for biochemical analyses. The increase in 24 h proteinuria, blood glucose level, serum creatinine, and blood urea of DN rats were conspicuously abated by AG1024. After biochemical analyses, the renal tissue specimens were collected, and as revealed by hematoxylin and eosin staining and Masson staining, AG-1024 mitigated typical renal damage and interstitial fibrosis in DN rats. Then, the anti-inflammatory effect of AG-1024 was assessed by western blotting and ELISA. Mechanistically, AG-1024 upregulated SOCS1 and SOCS3 expression and decreased phosphorylated JAK2, STAT1, and STAT3, as shown by western blotting. Collectively, AG-1024 (an IGF-1R inhibitor) ameliorates renal injury in experimental DN by attenuating renal inflammation and fibrosis via the SOCS/JAK2/STAT pathway.

At present, there are some problems in the construction of the intelligent mine, such as the non-uniform interface protocol and the formation of new 'information island'. They lead to the difficulty of data fusion and sharing in mines and the difficulty of realizing the high-quality development of intelligent mine. It is pointed out that the key problem of mine intelligent construction lies in the lack of standardized and unified data acquisition, transmission and sharing standards. According to the core specification, application specification, and operation and maintenance specification, the technology system of intelligent mine communication interface and protocol is designed. The communication interface and protocol model of intelligent mine is proposed. The perception layer, transmission layer and application layer of the model are defined. The model of intelligent mining equipment is constructed, and the communication interface is described formally. The intelligent mine data is divided into perception data, text data and audio-visual data. The message structures of the three kinds of data are defined. According to the current mining equipment, technology application and development direction, the intelligent mine data acquisition modes are divided into equipment direct acquisition, protocol conversion acquisition, and system transfer acquisition. The application scenarios of three data acquisition modes are pointed out. The acquisition and transmission process of perception data, text data, and audio-visual data are described. The technical specification of intelligent mine communication interface and protocol covers the whole process of mine data fusion communication. It provides unified interface mode and communication protocol specification for intelligent mine data acquisition, transmission, fusion and sharing. And it realizes interconnection and intercommunication among various systems of the mine.

ObjectiveTo explore the effect of home visit based on empowerment education on psychotic symptoms， self-management ability and well-being of schizophrenia patients in home rehabilitation.MethodsA total of 87 cases of schizophrenia patients who met the diagnostic criteria of International Classification of Diseases， tenth edition （ICD-10） and were recovering at home in Caiba town， Yibin city from January to July 2021 were selected by random sampling method as research subjects. They were divided into experimental group （n=43） and control group （n=44） according to the random number table method. The two groups received routine family visits， and the experimental group received family visits based on empowerment education. The intervention cycle of the two groups was 6 months. Before and after the intervention， the severity of psychotic symptoms， self-management ability and well-being of the patients in the two groups were assessed with the Brief Psychiatric Rating Scale （BPRS）， the Schizophrenia Self-Management Instrument Scale （SSMIS） and the Index of Well-Being Scale （IWB）.ResultsAfter intervention， the intra group comparison showed that the BPRS score in the experimental group was lower than that before the intervention （t=4.550， P

Objective To analyze the factors influencing intraoperative massive hemorrhage in infants with intracranial tumors and establish a bleeding risk scoring （BRS） model. Methods Clinical data of 278 infants who underwent elective intracranial tumor resection were retrospectively analyzed. According to the ratio of blood loss （BL） to estimated blood volume （EBV）, all infants were divided into the slight or moderate hemorrhage group （BL/EBV≤0.5） and massive hemorrhage group （BL/EBV > 0.5）. Relevant clinical data and hemorrhage were statistically analyzed. Univariate and multivariate logistic regression analyses were used to identify the independent risk factors for intraoperative massive hemorrhage and establish a BRS model. Forty-five infants undergoing intracranial tumor resection were recruited in this study. The receiver operating characteristic （ROC） curve was delineated to evaluate the performance of this model. Results One hundred and eighty-three infants were assigned into in the slight or moderate hemorrhage group and 95 in the massive hemorrhage group. Logistic regression analysis demonstrated that body weight ≥12 kg, tumor diameter ≥4.5 cm,and operation time ≥ 5 h were the independent risk factors for intraoperative massive hemorrhage （all P < 0.05）. The score of tumor diameter ≥4.5 cm was set as 5, and 2 for operation time≥5 h. The total score of infant was calculated as BRS. The area under the ROC curve （AUC） of BRS model in the retrospective population was 0.788. If the critical value for massive hemorrhage was determined as 5, the sensitivity was 66.8%, the specificity was 81.3%, and the accuracy was 71.0%, while in the prospective population, the ROC AUC was 0.909, the sensitivity, specificity and accuracy were 78.6%, 88.9% and 87.0%, respectively. Conclusions Preoperative tumor diameter≥4.5 cm and operation time≥5 h are the independent risk factors for intraoperative massive hemorrhage in infants undergoing intracranial tumor resection. The BRS model established based on these factors has high predictive ability for intraoperative massive hemorrhage in infants with intracranial tumors.

The micro-size flake silver powders were prepared through wet-chemical reduction method by using a micro-jet reactor. Herein ascorbic acid was used as a reducing agent, and sulfuric acid was used as a stabilizer. And the lauric acid was used as a dispersing agent to prevent particles’ agglomeration. The micro-jet reactor collides the two solutions together and uniformly mixes outside the reactor, to avoid the problem of clogging in the microchannel. The effects of dispersant addition and micro-jet flow rate on the morphology, particle size, and other parameters of silver powder is investigated in the present work. Interestingly, the addition of dispersant agent and stabilizer have a significant impact on the morphology and parameter of the silver particles. Under the conditions of micro-jet flow rate of 50 mL·min−1, sulfuric acid addition amount of 2%, and lauric acid addition amount of 0.8% by the weight of silver nitrate, a kind of flake silver powders with 4.40–4.70 μm can be prepared. The volume resistivity of the silver paste prepared from the obtained flake silver powders is in the range of 1.4–1.6 × 10−4 Ω·cm−1, which meets the application test requirements of conductive silver paste.

The composite nanocontainer of corrosion inhibitor (MSN-QB) was prepared by loading octahydroxyquinoline (8-HQ) and benzotriazole (BTA) on mesoporous silica nanoparticles(MSN) simultaneously using vacuum adsorption and layer-by-layer self-assembly technology, and added to the epoxy coating to obtain a new coating (MQB). SEM, TEM, FT-IR, Zeta-potential and TGA were used to study the structure changes of the nanocontainer before and after loading corrosion inhibitors and the stimulus response release behavior of the corrosion inhibitors, and electrochemical test and salt spray test were used to study the improvement of coating protection performance by layer-by-layer self-assembly technique. The results show that the loadings of 8-HQ and BTA in MSN-QB are 6.8%(mass fraction) and 7.1%, respectively. MSN-QB has pH response characteristics. The release of 8-HQ and BTA are both inhibited under neutral conditions, but can be released under alkaline (pH=10) and acidic (pH=4) conditions. The release rate under alkaline conditions is higher. MQB coating has the best corrosion resistance. After immersed in 3.5%NaCl solution 20 d, the MQB coating has the largest|Z|0.01 Hz value(2.0×109 Ω·cm2), more than twice that of MQ+MB coating.

The MoS2-doped graphite/copper self-lubricating composites (Gr-MoS2/Cu) were synthesized by a rapid microwave sintering procedure. In this paper, the thermal properties and friction behaviors of Gr-MoS2/Cu composites at room temperature to 200 °C were studied. The doping of molybdenum disulfide solid lubricant into graphite could promote the formation of friction film in the friction process, and optimize the friction and wear properties of graphite/copper composites. Meanwhile, the thermal and frictional properties of the composites at 200 °C are better than those at room temperature. In addition, the influence of the heat dissipation on the friction property of composites was analyzed and studied. The excellent heat dissipation property of the composites effectively mitigated the damage of the friction film and improved the friction property of the composites in the friction process.