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The need to improve formability and weight reduction in the automotive industry has greatly contributed to the development of transformation-induced plasticity (TRIP) steel. The stress–strain curve...

Traditional energy sources such as fossil fuels can cause environmental pollution on the one hand, and on the other hand, there will be a shortage of diminishing stocks. Recently, a variety of new energy sources have been proposed by scientists, such as nuclear energy, hydrogen energy, wind energy, water energy, and solar energy. There are already many technologies for converting and storing energy generated from new energy systems, such as various storage batteries. One of the keys to the commercialization of these new energy sources is to explore new materials. Researchers have performed a lot of research on new energy material preparation, mechanical properties, radiation resistance, energy storage, etc. However, new energy metal materials are still unable to combine radiation resistance, good mechanical properties, excellent energy storage, and other characteristics. There is still a lack of breakthrough materials with better performance or more stable structure. Recently, researchers have discovered that high-entropy alloys have become one of the most promising new energy metal materials. Because it not only has high energy storage and high strength, but also has high stability and high radiation resistance, and is easy to form a simple phase, the prediction of phases in high-entropy energy alloys is very critical, and the generation of designed phases in high-entropy energy alloys is a very important step. In this study, three machine learning algorithms were used to predict the generated phase classification in high-entropy alloys, namely, support-vector machine (SVM) model, decision tree (DT) model, and random forest (RF) model. The models are optimized by grid search methods and cross-validated, and performance was evaluated with the aim of significantly improving the accuracy of generative phase prediction, and the results show that the random forest algorithm has the best prediction ability, reaching 0.93 prediction accuracy. The ROC (receiver operating characteristic) curve of the model shows that the random forest algorithm has the best classification of solid-solution (SS) phases, where the classification probabilities AUC (area under the curve) area for amorphous phase (AM), intermetallic phase (IM), and solid-solution phase (SS), respectively, are 0.95, 0.96, and 1, respectively, , which can predict the generated phases of high-entropy energy alloys well.

Transformation Induced Plasticity (TRIP) steels with silicon&ndash, manganese (Si&ndash, Mn) as the main element have attracted a lot of attention and great interest from steel companies due to their low price, high strength, and high plasticity. Retained austenite is of primary importance as the source of high strength and high plasticity in Si&ndash, Mn TRIP steels. In this work, the cold rolled sheets of Si&ndash, Mn low carbon steel were treated with TRIP and Dual Phase (DP) treatment respectively. Then, the microstructure and composition of the Si&ndash, Mn low carbon steel were observed and tested. The static tensile test of TRIP steel and DP steel was carried out by a CMT5305 electronic universal testing machine. The self-built true stress&ndash, strain curve model of TRIP steel was verified. The simulation results were in good agreement with the experimental results. In addition, the phase transformation energy of retained austenite and the work borne by austenite in the sample during static stretching were calculated. The work done by austenite was 14.5 J, which was negligible compared with the total work of 217.8 J. The phase transformation energy absorption of retained austenite in the sample was 9.12 J. The role of retained austenite in TRIP steel is the absorption of excess energy at the key place where the fracture will occur, thereby increasing the elongation, so that the ferrite and bainite in the TRIP steel can absorb energy for a longer time and withstand more energy.

Tensile deformation behavior of Si–Mn TRIP (TRansformation Induced Plasticity) steel with vanadium and without vanadium and the DP (Dual Phase) steel of the same composition were studied in a large range of strain rate (0.001–2000 s −1 ) by routine material testing machine, rotation disk bar–bar tensile impact apparatus and high-speed material testing machine of servo-hydraulic type. In situ measurement of the transformation of retained austenite was performed by means of X-ray stress apparatus in order to have detailed knowledge about the transformation of retained austenite at quasi-static tensile. Microstructure of steels before and after tensile were observed by means of optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). It is shown that there is no yield plateau observed on the stress–strain curve at quasi-static condition for TRIP steel containing vanadium because the vanadium carbide suppress the formation of Cottrell atmosphere in matrix. Retained austenite of Si–Mn TRIP steel containing vanadium transforms to martensite at loading stress of 502 MPa (its yielding strength is 486 MPa), while the transformation of retained austenite in matrix of Si–Mn TRIP steel without vanadium happens when its yielding process is finished at quasi-static tensile. It is confirmed that phase transformation of retained austenite in TRIP steel is strain induced phase transformation. It is noted that tensile elongation of TRIP steel at dynamic tensile is always lower than that at quasi-static tensile. That is because gradually strain induced phase transformation of retained austenite in TRIP steel is suppressed by deformation localization at dynamic tensile.

Thermodynamics of martensite transformation in low alloy TRIP steel was evaluated. It follows from the calculation that ɛ phase might be formed at above room temperature in the low Mn steel. Tested steel was therefore prepared according to the estimation result. High volume fraction of retained austenite (above 20%) containing 1.37%C was obtained in the steel after continuous annealing treatment. Tensile test showed that the ultimate strength of the steel was 1248 MPa, elongation rate 25%, the product of strength and elongation rate 31200 MPa%, reaching the grade of the third generation automobile steel. XRD detection indicated that after tensile test there existed α′ martensite while TEM revealed that ɛ martensite also existed in the steel. Strengthening-toughening of the steel was thus raised due to the effect of transformation induced plasticity of two kinds of martensite. In addition, the phase stability of carbonitrates containing V was estimated and the complex micro-alloying effect was applied to the steel to control the size of austenite (about 1 μm) and enhance the stability of austenite.

Diffusion couples, Fe-6.8 wt% AI-1.0 wt% Si/Fe and Fe-6.3 wt% AI-0.9 wt% Si/Fe were constructed and separately annealed at 1050°C for 3 h and at 1000°C for 64 h. The concentration profiles of Fe, Al and Si atoms in these couples were measured by electron probe micro-analysis (EPMA), while the diffusion behavior was also simulated by coupling thermodynamic and kinetic properties of Fe-AI-Si system. The simulation results were in good agreement with the measured concentration profiles showing the validity of dynamic parameters of Fe-AI-Si system. Calculation was made for Fe-7 wt% Al-1 wt% Si/Fe diffusion couples at 1000°C with different diffusion time. Silicon uphill was found under the influence of aluminum.

Summary Introduction Severe acute respiratory syndrome (SARS) caused large outbreaks of atypical pneumonia in 2003, with the largest localized outbreak occurring in Beijing, China. Lymphopenia was prominent amongst the laboratory abnormalities reported in acute SARS. Methods The effect of SARS on peripheral blood lymphocytes and their subsets was examined in 271 SARS coronavirus-infected individuals. Results There was a significant decrease in the CD45+, CD3+, CD4+, CD8+, CD19+ and CD16+/56+ cell counts over the five weeks of the SARS illness although CD4+/CD8+ ratios did not change significantly. The lymphopenia was prolonged, reaching a nadir during days 7–9 in the second week of illness before returning towards normal after five weeks, with the lowest mean CD4+ cell count of 317 cells×10 6 /L at day 7, and CD8+ cell count of 239 cells×10 6 /L at day 8. Patients with more severe clinical illness, or patients who died, had significantly more profound CD4+ and CD8+ lymphopenia. Discussion Lymphopenia is a prominent part of SARS-CoV infection and lymphocyte counts may be useful in predicting the severity and clinical outcomes. Possible reasons for the SARS-associated lymphopenia may be direct infection of lymphocytes by SARS-CoV, lymphocyte sequestration in the lung or cytokine-mediated lymphocyte trafficking. There may also be immune-mediated lymphocyte destruction, bone marrow or thymus suppression, or apoptosis.

The evaluation index of the control of the disease cost is an important part of the Medical quality and safety index. The purpose of this study is to Establishment of the Evaluation index System and Evaluation Criterion of the Cost Control. This dissertation has analyzed the formulation method and procedures of the appraisal indicators of the cost control of the disease through the research and analysis of the cost control standard of the pure cesarean operation. We should improve medical quality and safety, decrease health care costs, high efficiency and low consumption in the development path.

From perspective of the stock ownership control rate of foreign investment, an enterprise is relatively controlled if the stock ownership controlling rate exceeds 20 %, it is absolutely controlled if the stock ownership control rate exceeds 50 %. The controlling rate of FDI over Chinese enterprises of equipment manufacturing and high-tech industry is higher than overall industrial controlling rate. As a result, Chinese industry may lose independent innovation and self-development capacity. The Countermeasures to maintain Chinese industrial security are the government should create a suitable survival and development environment for the strategic industries.

With strong public and social recognize, insurance business involves all walks of life and thousands of families, and it bears certain social responsibilities and obligations. Insurance industry’s major business is to operate risk. Its security is of great significance for the stable operation of the entire financial industry. This work design a scientific evaluation index system to analyze and evaluate the security of the Chinese insurance industry by External environment (Macroeconomic environment, Industry controlling power, Industry developing power) and Internal environment (Market size, Profitability, Liquidity of assets) is an important practical significance.

Background Amyotrophic Lateral Sclerosis (ALS) is a progressive, adult onset, fatal neurodegenerative disease of motor neurons. There is emerging evidence that alterations in RNA metabolism may be critical in the pathogenesis of ALS. MicroRNAs (miRNAs) are small non-coding RNAs that are key determinants of mRNA stability. Considering that miRNAs are increasingly being recognized as having a role in a variety of neurodegenerative diseases, we decided to characterize the miRNA expression profile in spinal cord (SC) tissue in sporadic ALS (sALS) and controls. Furthermore, we performed functional analysis to identify a group of dysregulated miRNAs that could be responsible for the selective suppression of low molecular weight neurofilament (NFL) mRNA observed in ALS. Results Using TaqMan arrays we analyzed 664 miRNAs and found that a large number of miRNAs are differentially expressed in ventral lumbar SC in sALS compared to controls. We observed that the majority of dysregulated miRNAs are down-regulated in sALS SC tissues. Ingenuity Pathway Analysis (IPA) showed that dysregulated miRNAs are linked with nervous system function and cell death. We used two prediction algorithms to develop a panel of miRNAs that have recognition elements within the human NFL mRNA 3′UTR, and then we performed functional analysis for these miRNAs. Our results demonstrate that three miRNAs that are dysregulated in sALS (miR-146a*, miR-524-5p and miR-582-3p) are capable of interacting with NFL mRNA 3′UTR in a manner that is consistent with the suppressed steady state mRNA levels observed in spinal motor neurons in ALS. Conclusions The miRNA expression profile is broadly altered in the SC in sALS. Amongst these is a group of dysregulated miRNAs directly regulate the NFL mRNA 3′UTR, suggesting a role in the selective suppression of NFL mRNA in the ALS spinal motor neuron neurofilamentous aggregate formation.

The sensitivities and specificities of an immunofluorescence assay and an enzyme immunoassay for detection of antibodies specific for severe acute respiratory syndrome coronavirus (SARS-CoV) were compared for 148 laboratory-confirmed SARS cases. The appearance and persistence of SARS-CoV-specific antibodies were assessed, with immunoglobulin G detected in 59% of samples collected within 14 days and persisting for 60 to 95 days after the onset of illness.

Background Severe acute respiratory syndrome (SARS) caused a large outbreak of pneumonia in Beijing, China, in 2003. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to detect and quantify SARS-CoV in 934 sera and self-collected throat washes and fecal samples from 271 patients with laboratory-confirmed SARS managed at a single institution. Results SARS-CoV detection rates in sera were highest in the first 9 days of illness, whereas detection was highest in throat washes 5–14 days after onset of symptoms. The highest SARS-CoV RT-PCR rates (70.4–86.3%) and viral loads (log10 4.5–6.1) were seen in fecal samples collected 2–4 weeks after the onset of clinical illness. Fecal samples were frequently SARS-CoV RT-PCR positive beyond 40 days, and occasional sera still had SARS-CoV detected after 3 weeks of illness. Conclusion In the context of an extensive outbreak with major pressure on hospital resources, patient self-collected samples are an alternative to nasopharyngeal aspirates for laboratory confirmation of SARS-CoV infection.

To study etiology of clinically diagnosed non A-E hepatitis.HBV, TTV, human parvovirus B19, SENV DNA were detected by nested polymerase chain reactions (nPCR), while HGV, HCV RNA were tested by reverse transcription nested polymerase chain reactions (RT-nPCR).Of 60 patients with clinically diagnosed non A-E hepatitis, 30 (50.0%) were HBV DNA positive alone, 10 (16.7%) HBV and TTV DNA positive, 6 (10.0%) HBV and B19 DNA positive; 1 (1.7%) HBV, SENV DNA and HCV RNA positive, 1 (1.7%) HCV RNA positive alone, 1 (1.7%) HCV RNA and B19 DNA positive, 2 (3.3%) B19 DNA positive alone, 1 (1.7%) TTV DNA positive alone, and the remaining 8 (13.3%) negative for all viruses. All the 60 patients were HGV RNA negative. There were no differences in serum biochemical markers of hepatitis B patients with or without TTV or B19 virus infection.HBV is a major etiologic agent for the clinically diagnosed non A-E hepatitis. HGV, TTV, B19 and SEBV may not be associated with nonA-E hepatitis.