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In order to investigate the microstructure uniformity and plasticity of hot-rolled 0Cr21A16 alloy sheet and im prove its high temperature and cold working characteristics， heat treatment tests and microstructure properties analysis were carried out at different temperatures. The microstructure and mechanical properties of 0Cr21Al6 alloy sheet before and after heat treatment were studied by optical microscopy， X-ray diffraction （XRD）， Gleeble high temperature thermal tensile test， scanning electron microscopy （SEM） and nanoindentation. The results show that the microstructure unifor mity of 0Cr21Al6 alloy sheet can be improved by heat treatment， and the average grain size is about 42 μm after holding at 960 ℃ for 6 min 40 s， and the overall grain size is relatively uniform and fine compared with at 940、980、1 000、1 020 ℃ heat treatment， the hardness and plasticity are the best combination， and the fracture toughness KIC is the best after 960 ℃ heat treatment. With the best comprehensive performance， it can effectively avoid the brittle fracture of materials in the production process. In addition， Gleeble test shows that the heat treatment temperature over 1 000 ℃ is no longer suitable for hot processing.

The competition for cyber security is ultimately the competition of talents. Countries around the world have placed cyber security talents at the national strategic level. As a new interdisciplinary subject, the intension and extension of cyber security discipline is still evolving and developing. So far, it lacks a talent training mode and evaluation mechanism suitable for the characteristics of cyber security talents. Based on years of teaching research, with reference to the existing advanced training models and evaluation mechanisms in foreign countries, combined with the actual situation in China, an innovative training mode of “cybersecurity doctor” suitable for the characteristics of cybersecurity disciplines is proposed. It covers the whole life cycle of undergraduate training. With problem orientation, students are trained to find security problems and solve them in cyberspace. Universities, industry and research institutions are closely interacting. Furthermore, it improves students' knowledge, skills and practical application ability, develops interest and ability to explore the latest advanced and core technologies, improves the quality of our teachers and education, and also helps enterprises select outstanding talents, enhance their research and development capabilities and market competitiveness. In the end, the two sides will achieve synergy and innovation, complement each other, and achieve a comprehensive win-win situation, and promote the cultivation of cyber security talents and the development of disciplines.

BackgroundBoron carbide (B4C) aluminum matrix composite has a wide application prospect in the field of nuclear power plant spent fuel storage shielding neutron due to the large neutron absorption cross section of B isotope 10B in B4C.PurposeThis study aims to investigate the response mechanism of current effect on the internal microstructure and mechanical properties of neutron absorbing materials.MethodsThe 30wt.% B4C/6061Al neutron absorbing material was prepared by multi-pass rolling after vacuum hot pressing. Electropulsing treatment (EPT) was applied to the heat treatment of prepared materials, and the skin effect and joule effect of current were made use of eliminating the defects and residual stresses at the particle/matrix interface. Finally, energy disperse spectroscopy (EDS), electron backscatter diffractometer (EBSD) and scanning electron microscope (SEM) were employed to observe the microstructure morphology and particle / matrix interface of the samples under different process parameters.ResultsThe results show that the EPT can promote the degree of recrystallization of the matrix alloy, healing heterogeneous particle/matrix interface of micro defects, improve the bonding strength of interface, inhibit grain growth of the matrix alloy, and reduce the interfacial residual stress. With the extension of time of applying pulse current, the tensile strength and elongation of the composite material showed a trend of increase, up to 245.2 MPa and 9.02%, the load transfer effect of B4C particles is enhanced, and the non-thermal effect of current play a leading role.ConclusionsEPT can improve the mechanical properties of B4C aluminum base neutron absorbing material.

With the development of seismic isolation technology, the service environment of the isolated bridge is becoming increasingly complicated, and the effect of ambient temperature on the seismic performance of isolated bridge should be considered urgently. To reduce the maximum response and residual deformation of the bridge under the action of an earthquake, combining the advantages of the lead rubber bearing (LRB) and shape memory alloy (SMA), a self-resetting SMA-LRB bearing was formed. In view of the temperature sensitivity of rubber and SMA materials, based on a 4-span SMA-LRB seismic isolation continuous girder bridge, the nonlinear dynamic time history analysis of isolated continuous girder bridges under different ambient temperatures was performed to obtain the dynamic response of the key parts of the structure, while the mechanical properties of SMA-LRB bearings at different ambient temperatures were considered. The results showed that the addition of SMA to LRB increased the horizontal rigidity and effectively controls the displacement response of the bearing. At the same time, the self-reset characteristic of SMA made the residual displacement control effective. As the ambient temperature decreases, the peak displacement and residual displacement of the LRB and SMA-LRB bearings would decrease, but the displacement control ability and self-reset ability of the SMA-LRB bearing would decrease compared with normal temperature. The stiffness of the bearing increased with the decrease of the ambient temperature, which caused an increment in the displacement of the top of the pier and the shear force at the bottom of the pier, and the shear force at the bottom of the lower pier was more sensitive to temperature changes. The qualitative evaluation of the influence of ambient temperature on the seismic performance of SMA-LRB isolated bridge can provide reference for the analysis and design of such bridges. [ABSTRACT FROM AUTHOR]

To help railway express freight transportation adapt to the requirement of logistics better, this paper investigated the hub-and spoke service network design problem for express freight train running between railway logistic terminals. By considering customer leading-time and train-type requirements and railway line capacity constraints, it formulated the problem as a mixed integer linear programming model to minimize the total costs including fixed costs, variable costs and penalty cost. it designed a genetic algorithm according to the characteristics of the model and the scale of the problem. At last, it collected a realistic example to conduct case study. Computational results show that the proposed model and algorithm can effectively describe and solve practical problem. This optimization ideas and methods of hub-and-spoke-based service network design have a certain referential significance to the organization of railway express freight transportation. [ABSTRACT FROM AUTHOR]

From 2005 to 2010, also known in China as the “Eleventh Five Year” period, Chinese historians published over 70 books and 100 plus articles on Latin American history. The article categorizes research accomplishments in the following areas: general history, specific historical topics, international relationships, political research, economic research, and social movement research. Latin American research in China is still weak; few universities include it in their curriculum. Only two universities offer doctoral degrees on the topic. The author hopes that Latin American history research will gain more momentum during the "Twelfth Five Year period." The article also provides a list of topics that should be further researched.

Background: Targeted therapy has become an indispensable therapy method in advanced non-small cell lung cancer (NSCLC) treatment. Epithelial growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) can significantly prolong the survival of patients harboring EGFR gene mutation. Icotinb is China's first EGFR-TKI with independent intellectual property rights. The aim of this study is to investigate the clinical characteristics about the beneficiary of advanced NSCLC patients with EGFR Common mutation who were treated with Icotinib. Retrospectively collect the data about beneficiary [progression-free survival (PFS)≥6 months] and analysis of the related risk factors for prognosis., Methods: From September 1, 2011 to September 30, 2015, 231 cases of advanced NSCLC beneficiary with EGFR common mutation were enrolled for treatment with icotinib in Zhejiang Cancer Hospital., Results: The one year benefit rate was 67.9% in the group treated with Icotinib as first line, and in the groupas second line or above was 53.6%, which is statisticallysignificant. The two years benefit rate was 18.7% and 9.3%, respectively. The median PFS of first line group and the second line or above was 16.7 and 12.4 months, respectively. The presence of brain metastasis (P=0.010), Prior chemotherapy (P=0.001), Eastern Cooperative Oncology Group (ECOG) score (P=0.001) were the main factors influencing the prognosis. The most common adverse were skin rashes (51 cases, 22.1%) and diarrhea (27 cases, 11.7%)., Conclusions: Icotinib offers long-term clinical benefit and good tolerance for advanced NSCLC harboring EGFR gene mutation. Its advantage groups in addition to the patients with brain metastases and better ECOG score, the curative effect of patients with the first-line treatment is superior to second or further line. 
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Objective: This study aims to evaluate the efficacy and safety of crizotinib for advanced ALK-positive non-small cell lung cancer (NSCLC) patients., Methods: Twenty-eight patients with advanced ALK-positive NSCLC were given orally crizotinib 250 mg b. i.d., and were followed up to evaluate the therapeutic efficacy and safety., Results: Among the 28 patients, the objective response rate (ORR) was 71.4% (20/28) and disease control rate (DCR) was 92.9% (26/28). Three patients achieved complete response. Seventeen patients had partial response. The most common drug-related adverse events were mild flickering vision and gastrointestinal reaction. Eleven patients experienced flickering vision. Nine patients had nausea and vomiting. Eight patients had diarrhea. They were all reversible and of grade I or II. Only one patient had grade III myelosuppression. Among the 28 patients, 16 cases were disease-free and 12 cases had progressive disease, with a progression-free survival of 8.2 months., Conclusions: Crizotinib is effective and tolerable in the treatment of advanced ALK-positive NSLCC. However, its long-term treatment efficacy requires to be further studied.