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After phosphate treatment, the surface of mechanical parts has color differences of film, roughness and no film, and the properties of phosphating film could not meet the process requirements. Through comparison and analysis of literature, it was found that the physical or chemical changes took place on the surface of parts while forming parts by various processing methods, which meant the surface structure, surface composition, surface stress and other states of the parts were changed; the differences of surface state had different effects on phosphating reaction rate. Therefore, different pretreatment methods should be adopted for various surface states during phosphate treatment of mechanical parts to improve the phosphating film formation condition. In this way, uniform phosphating film could be formed on the surface of parts.

As a consortium blockchain with the multi-center characteristics of public blockchain and the high-performance advantages of private blockchain,it has become the center of development of China.Combined with the characteristics of node trust in the consortium blockchain,non-byzantine fault tolerance consensus algorithm can provide better performance support for the consortium blockchain.By selecting Raft consensus algorithm as the research object,focusing on the leader election and log replication process in the Raft consensus algorithm,this paper proposes a non-byzantine fault tolerance consensus algorithm for consortium blockchain Kraft(Kademlia-Raft) consensus algorithm.It improves the process of Leader election and log replication in the Raft consensus algorithm by combining the two-layer Kademlia routing protocol.First,in view of the problem of voting efficiency caused by the number of Candidate nodes and the increase of Follower nodes in the Raft consensus algorithm,KRaft consensus algorithm uses K-bucket established by the two-layer Kademlia protocol to realize the stable election in the Candidate node set.Se-condly,in view of the low efficiency of the single-node log replication process of the Leader in the log replication process of Raft consensus algorithm and the load balance problem on the nodes,a parallel log replication scheme of multiple Candidate nodes is proposed to equalize the load on the Leader node,so as to improve the data throughput and the scalability of the algorithm at the same time.Finally,the local multi-node simulation experiment shows that the data throughput of KRaft consensus algorithm is increased by 34.5% compared with Raft consensus algorithm,the voting speed of Leader node is increased by 55.6%.

Ferrosilicon alloy is widely used as alloying agent and deoxidizer in the steelmaking process, which containing the metallic impurities of Al, Ca, and Ti would directly affect the cleanliness of the molten steel. Therefore, metallic impurities from the ferrosilicon alloy removed by the top blowing Ar-O2 gas was carried out. The morphology, composition, and area fraction of impurity phases of metallic impurities in the ferrosilicon alloy were compared before and after Ar-O2 gas blowing treatment by automatic scanning electron microscopy, and contents of metallic impurities were measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). The results show that a large amount of metallic impurity phases precipitate in the ferrosilicon alloy raw material, which mainly contain Al, Ca, and Ti impurities, and their contents are 1.11% (mass fraction, the same below), 0.31% and 0.11%, respectively. After blowing Ar-O2 gas for 5 minutes, contents of Al and Ca are dropped sharply to 0.66% and 0.13%, respectively. After blowing Ar-O2 gas from 45 minutes, the removal rate of impurity elements is slowed down and the refining reaction tends to reach equilibrium. After 120 minutes of blowing Ar-O2 gas, contents of Al, Ca and Ti are 0.42%, 0.014% and 0.094%, respectively; meanwhile the removal efficiency of Al, Ca and Ti are 62.16%, 95.48% and 14.54%, respectively. The refining method of blowing Ar-O2gas can effectively remove impurity elements of Al and Ca in the ferrosilicon alloy, while no significant change in Ti content is found.

Introduction: The objective of this study is to evaluate and compare the effectiveness of endovenous microwave ablation (EMA) and high ligation and strippingn (HLS) of the great saphenous vein (GSV) in the treatment of varicose veins. Methods: We included 182 patients in each EMA and HLS groups. Follow-up outcomes included AVVQ, VCSS, chronic venous insufficiency questionnaire-14 (CIVIQ14) score, clinical recurrence rate of varicose vein treatment, and patient satisfaction during the 1-year follow-up period. Results: At the 1-year follow-up, no significant difference was found in the clinical recurrence rate of varicose veins between the EMA and HLS groups (p =.75). The duration of the operation and the length of hospital stay for patients in the EMA group was shorter than that for the HLS group (p <.01). The Aberdeen Varicose Vein Questionnaire (AVVQ), Venous Clinical Severity Score (VCSS) score, and ecchymosis were lower for patients who underwent EMA surgery (p <.01). Conclusion: Our research results confirm that EMA improves patients' quality of life with lower limb varicose veins, with EMA showing higher patient satisfaction. [ABSTRACT FROM AUTHOR]

BACKGROUND The Bayan Obo mining area is the main producing area of rare earth elements. During mining and refining, rare earth elements enter plants through migration and enrichment. Study on the distribution characteristics and migration patterns of rare earth elements will provide data support for bioremediation following the closure of the Bayan Obo ore body pit. OBJECTIVES To study the distribution characteristics and migration patterns of rare earth elements in soil and plants. METHODS Seven soil sampling points were set up, and seven plant types including Honeysuckle, Artemisia desertorum, Astragalus Adsurgens Pall, Agriophyllum squarrosum (L.) Moq, Artemisia carvifolia, Populus simonii Carr and Salsola collina Pall were collected. The content of rare earth elements in soil and roots, stems, leaves (or flowers) and whole plants was determined by inductively coupled plasma-mass spectrometry. RESULTS With the increase of the distance between the sampling area and the main mining area, the rare earth element content in the soil samples decreased. The rare earth element content of Honeysuckle was the highest in the studied plants, whereas it was the lowest in Artemisia carvifolia. The rare earth element content in whole plant and various parts (root, stems, leaves or flowers) in different plants were analyzed by multiple linear regression analysis. The rare earth element content of leaves (or flowers) accounted for the largest proportion in whole bead plants. In addition, the content of rare earth elements in plants was basically unchanged in different seasons. The rare earth elements with higher content were 0.0035%-0.020%, 0.0012%-0.011%, 0.0010%-0.0094% and 0.00036%-0.0046% for Ce, La, Nd and Pr, respectively. CONCLUSIONS According to the gradual reduction pattern of rare earth elements in soil samples, the rare earth source of the soil around the mining area may be caused by the diffusion of ore during mining and refining. According to the rare earth enrichment ability of plants, Honeysuckle with strong enrichment ability of rare earth can be used for bioremediation of mines, after the mine is closed.