The high-temperature magnetic perfo rmance and micro structure of Sm_(1-x)Gd_(x)(Co_(bal)Fe_(0.09)Cu_(0.09)Zr_(0.025))_(7.2)(x=0.3,0.5) magnets were *** the isothermal aging time decreasing from 11 to 3 h,the temperat...
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The high-temperature magnetic perfo rmance and micro structure of Sm_(1-x)Gd_(x)(Co_(bal)Fe_(0.09)Cu_(0.09)Zr_(0.025))_(7.2)(x=0.3,0.5) magnets were *** the isothermal aging time decreasing from 11 to 3 h,the temperature coefficient of intrinsic coercivity in the temperature range of 25-500℃,β_(25-500℃),was optimized from -0,167%/℃ to-0.112%/℃ for x=0.3 *** noticeable enhancement(~33%) of temperature stability is correlated with the increased content of 1:5H cell boundary phase and its relatively high Curie temperature as ***,for the x=0.5 magnet,it is found that the presence of Sm_(5)Co_(19) phases and wider nanotwin variants hinder the formation of 1:5H cell boundary *** insufficient 1:5H is not beneficial to the proper redistribution of Cu in cell boundary,making the x=0.5 magnet difficult to achieve higher temperature ***,the approach of adjusting the isothermal aging process can offer guidance for attaining superior magnetic performance in the temperature range from 25 to 500℃ for Gd-substituted Sm_(2)Co_(17)-type magnets.
During resistance spot welding of zinc-coated advanced high-strength steels (AHSS), cracks which are promoted by liquid metal embrittlement (LME) may occur. According to previous researches, welding current, welding t...
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Sacrificial metallic coatings are an effective strategy for mitigating corrosion in steel operating in industrial environments. This review article focuses on examining the protection mechanism of zinc-aluminum-magnes...
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Sacrificial metallic coatings are an effective strategy for mitigating corrosion in steel operating in industrial environments. This review article focuses on examining the protection mechanism of zinc-aluminum-magnesium(Zn-Al-Mg) coatings on steel substrates. Specifically, it investigates the effects of various elements and their corrosion products on the corrosion resistance of Zn-Al-Mg coatings. Furthermore, this review summarizes the formation mechanisms of various specialized corrosion modes that occur following the corrosion of Zn-Al-Mg coatings, based on previous experimental findings. It also includes suggestions for further research areas that could contribute to the development of highly corrosion-resistant and long-lasting coatings. These suggestions are based on published laboratory and field test results available in literature.
A mathematical model of the decarburization reaction zone was established for the Ruhrstahl–Heraeus (RH) forced oxygen blowing decarburization process by Matlab R2022b software. For the problem of inaccurate predicti...
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A mathematical model of the decarburization reaction zone was established for the Ruhrstahl–Heraeus (RH) forced oxygen blowing decarburization process by Matlab R2022b software. For the problem of inaccurate prediction due to the large variation range of oxygen absorption rate under different process conditions, we statistically analyzed the main factors affecting the oxygen absorption rate. The backpropagation neural network was used to train and predict the oxygen absorption rate and was used to calculate the RH decarburization reaction zone model. We designed and developed a mathematical modeling software with processcontrol of decarburization in RH degasser, which can realize the change of operating process parameters in the dynamic prediction process. The optimized mathematical model has more than 95% of the furnaces whose absolute error in calculation of carbon content is within ± 5 × 10^(−6), more than 90% of the heats whose relative error in calculation of oxygen content is within ± 15%, and the average absolute error of calculation of oxygen content is 26.4 × 10^(−6). Finally, we studied the influence of oxygen blowing timing, oxygen blowing volume and initial oxygen content on the forced decarburization process.
The dendrite growth behavior of high-strength steel during slab continuous casting with a traveling-wave magnetic field was studied in this paper. The morphology of the solidification structure and composition distrib...
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The dendrite growth behavior of high-strength steel during slab continuous casting with a traveling-wave magnetic field was studied in this paper. The morphology of the solidification structure and composition distribution were analyzed. Results showed that the columnar crystals could deflect and break when the traveling-wave magnetic field had low current intensity. With the increase in current intensity, the secondary dendrite arm spacing and solute permeability decreased, and the columnar crystal transformed into an equiaxed crystal. The electromagnetic force caused by the traveling-wave magnetic field changed the temperature gradient and velocity magnitude and promoted the breaking and fusing of dendrites. Dendrite compactness and composition uniformity were arranged in descending order as follows:columnar-toequiaxed transition (high current intensity), columnar crystal zone (low current intensity), columnar-to-equiaxed transition (low current intensity), and equiaxed crystal zone (high current intensity). Verified numerical simulation results combined with the boundary layer theory of solidification front and dendrite breaking–fusing model revealed the dendrite deflection mechanism and growth process. When thermal stress is not considered, and no narrow segment can be found in the dendrite, the velocity magnitude on the solidification front of liquid steel can reach up to 0.041 m/s before the dendrites break.
In this work,boron(B)was used to promote Fe^(3+)/peracetic acid(Fe^(3+)/PAA)for the degradation of sulfamethazine(SMT).An SMT degradation efficiency of 9.1%was observed in the Fe^(3+)/PAA system over 60 min,which was ...
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In this work,boron(B)was used to promote Fe^(3+)/peracetic acid(Fe^(3+)/PAA)for the degradation of sulfamethazine(SMT).An SMT degradation efficiency of 9.1%was observed in the Fe^(3+)/PAA system over 60 min,which was significantly increased to 99.3%in the B/Fe^(3+)/PAA system over 10 *** B/Fe^(3+)/PAA process also exhibited superior resistance to natural substances,excellent adaptability to different harmful substances,and good removal of antibiotics in natural fresh water *** mechanism of action of boron for Fe^(3+)reduction was determined using scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),Fourier transform infrared(FT-IR)spectroscopy,density functional theory(DFT)calculations,and electrochemical *** dominant role of^(·)OH was confirmed using quenching experiments,electron spin resonance(EPR)spectroscopy,and quantitative *** radicals(R-O^(·))and Fe(IV)also significantly contribute to the removal of *** calculations on the reaction between Fe^(2+)and the PAA were conducted to further determine the contribution from ^(·)OH,R-O^(·),and Fe(IV)from the perspective of thermodynamics and the reaction *** boron dosages,Fe^(3+)dosages,and initial pH values were also investigated in the B/Fe^(3+)/PAA system to study their effect of SMT removal and the production of the reactive ***(IV)production determined the k_(R-O·+Fe(IV))value suggesting that Fe(IV)may play a more important role than R-O^(·).A comparison of the results with other processes has also proved that the procedure described in this study(B/Fe^(3+)/PAA)is an effective method for the degradation of antibiotics.
The vacuum thermal evaporation technique was used to simultaneously deposit zinc coatings onto interstitial free steel plates and single-crystal silicon wafers in a high vacuum *** effect of substrate temperature on t...
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The vacuum thermal evaporation technique was used to simultaneously deposit zinc coatings onto interstitial free steel plates and single-crystal silicon wafers in a high vacuum *** effect of substrate temperature on the mor-phology and crystal orientation of zinc coatings was *** the substrate temperature was 25 and 50℃,the zinc crystallites were plate-like and grew under a particular angle to the substrate *** the substrate was heated to 100℃,the zinc crystallites were regular hexagonal and arranged almost parallel to the substrate *** addition,observation of pure zinc coatings with different thicknesses showed that the growth of zinc coating was mainly in the Volmer-Weber *** the process parameters were appropriate,the zinc coating was composed of closely arranged columnar crystallites,and the crystallites grew preferentially along[0001]direction.
With the development of customization and flexibility of manufacturing industry,intelligent manufacturing process gradually presents multimodal characteristics,which are reflected in the strong coupling,nonlinear,mult...
With the development of customization and flexibility of manufacturing industry,intelligent manufacturing process gradually presents multimodal characteristics,which are reflected in the strong coupling,nonlinear,multi working conditions and other characteristics of the *** this paper,a multi-modal process monitoring method based on dynamic expansion is *** view of the dynamic characteristics of process data,the process data is dynamically expanded through the amplification matrix,and then the multi-modal process data is modal divided through the improved K-means *** divided multi-modal process data is monitored using Variational Autoencoder,and relevant statistics and control limits are ***,the multi-modal process monitoring is constructed by introducing the method of random forest for modal *** validity of the algorithm is verified by real data of steel rolling process.
Traditional tumor models do not tend to accurately simulate tumor growth in vitro or enable personalized treatment and are particularly unable to discover more beneficial targeted *** address this,this study describes...
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Traditional tumor models do not tend to accurately simulate tumor growth in vitro or enable personalized treatment and are particularly unable to discover more beneficial targeted *** address this,this study describes the use of threedimensional(3D)bioprinting technology to construct a 3D model with human hepatocarcinoma SMMC-7721 cells(3DP-7721)by combining gelatin methacrylate(GelMA)and poly(ethylene oxide)(PEO)as two immiscible aqueous phases to form a bioink and innovatively applying fluorescent carbon quantum dots for long-term tracking of *** GelMA(10%,mass fraction)and PEO(1.6%,mass fraction)hydrogel with 3:1 volume ratio offered distinct pore-forming characteristics,satisfactorymechanical properties,and biocompatibility for the creation of the 3DP-7721 *** analysis and quantitative real-time fluorescence polymerase chain reaction(PCR)were used to evaluate the biological properties of the *** with the two-dimensional culture cell model(2D-7721)and the 3D mixed culture cell model(3DM-7721),3DP-7721 significantly improved the proliferation of cells and expression of tumor-related proteins and ***,we evaluated the differences between the three culture models and the effectiveness of antitumor drugs in the three models and discovered that the efficacy of antitumor drugs varied because of significant differences in resistance proteins and genes between the three *** addition,the comparison of tumor formation in the three models found that the cells cultured by the 3DP-7721 model had strong tumorigenicity in nude *** evaluation of the levels of biochemical indicators related to the formation of solid tumors showed that the 3DP-7721 model group exhibited pathological characteristics of malignant tumors,the generated solid tumors were similar to actual tumors,and the deterioration was *** research therefore acts as a foundation for the application of 3DP-7721 models in drug devel
Based on software radio technique, a novel improved design structure of digital Costas loop for spread spectrum communication is put forward in the paper. Main practical works includes: (1) For carrier recovery in the...
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Based on software radio technique, a novel improved design structure of digital Costas loop for spread spectrum communication is put forward in the paper. Main practical works includes: (1) For carrier recovery in the traditional Costas central, it improves a way applicable to the spread spectrum communication and gives a detailed mathematical deduction; (2) As for traditional QPSK modern methods, it joins the encoding, interleaving, de-interlacing, decoding, balanced module in the QPSK modulation and demodulation process in spread spectrum communications to reduce the system Bit error rate (BER); (3) a PN code magna-scope demodulator and two low power filers are added in order to get sensitive weighing signal. Simulation contrast results show that the improvement is feasible.
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