Toughening mechanisms of a high-strength acicular ferrite steel heavy plate

An ultra-low carbon acicular ferrite steel heavy plate was obtained with an advanced thermo-mechanical control process-relaxed precipitation controlled transformation （TMCP-RPC） at Xiangtan Steel, Valin Group. The heavy plate has a tensile strength of approximately 600 MPa with a lower yield ratio. The impact toughness of the heavy plate achieves 280 J at ？40°C. The fine-grained mixed microstructures of the heavy plate mainly consist of acicular ferrite, granular bainite, and polygonal ferrite. The high strength and excellent toughness of the heavy plate are attributed to the formation of acicular ferrite microstructure. The prevention of blocks of martensite/retained austenite （M/A） and the higher cleanness are also responsible for the superior toughness.

中文版特发性肺纤维化患者生活质量量表在间质性肺疾病患者中的信效度研究

目的评价中文版特发性肺纤维化患者生活质量量表(Chinese version of a tool to assess quality of life in idiopathic pulmonary fibrosis,cATAQ-IPF)在间质性肺疾病(interstitial lung diseases,LD)患者中的信效度。方法使用量表引进方法形成中文版ATAQ-IPF(cATAQ-IPF)。量表的内容效度通过6名专家评价获得。共92例ILD患者完成cATAQ-IPF,圣乔治呼吸问卷(St.George's respiratory questionnaire,SGRQ)和英国医学研究委员会呼吸困难量表的基线评估。15例符合纳人排除标准的受试者在2周后完成了cATAQ-IPF的重测信度检验。收集的数据用于评价cATAQ-IPF的组内相关系数、Cronbach's a内部一致性信度、内容效度、皮尔森相关系数,校标关联效度和已知族群效度。结果cATAQ-IPF具有良好的重测信度,组内相关系数为0.95。量表有良好的组内一致性信度,除治疗维度Cronbach'sa为0.60外,其余维度Cronbach'sa为0.96。量表水平的内容效度指数(S-CVI)为0.80,条目水平的内容效度指数(I-CVI)为0.78~1.00,内容效度较好。cATAQ-IPF得分与SGRQ总分显著相关(r=0.71,P<0.01),校标关联效度理想。ILD患者cATAQ-IPF得分为(250.74±47.39)分,,IPF患者cATAQ-IPF得分为(287.90±22.56)分。根据cATAQ-IPF评估,IPF患者健康相关生活质量受到更多损害(t=4.94,P<0.01)。结论cATAQ-IPF可用于评价中国ILD患者,是具有良好信效度的评估工具。

Effects of self-management education on quality of life of patients with chronic obstructive pulmonary disease

Purpose:To explore the effects of self-management education on the quality of life of patients living with chronic obstructive pulmonary disease(COPD).Methods:Eighty-four stable or discharged COPD subjects were recruited from April 2011 to January 2012 following treatment at Beijing Hospital or Peking Union Medical College Hospital.Subjects were divided into an intervention group who underwent selfmanagement education or a control group who received usual care without additional education(n=42 each).The St George’s Respiratory Questionnaire(SGRQ)was used to measure quality of life at three and six months.Results:SGRQ impact domain scores revealed significant differences between the groups(t=2.167,p<0.05)at threemonths.SGRQsymptom,impact,activity domain and total scores revealed significant differences between groups(t=3.482 to2.530,p<0.05)at six months.Conclusion:A nurse-led,simple,structured self-management education program provided an effective method for the management of patients with COPD.

Hydrogen Embrittlement of Advanced High-Strength Steel for Automobile Application:A Review

The hydrogen embrittlement(HE)fracture of advanced high-strength steels used in lightweight automobiles has received increasing public attention.The source,transmission,and movement of hydrogen,characterization parameters,and test methods of HE,as well as the characteristics and path of HE fractures,are introduced.The mechanisms and modes of crack propagation of HE and hydrogen-induced delayed fracture are reviewed.The recent progress surrounding micro and macro typical fracture characteristics and the influencing factors of HE are discussed.Finally,methods for improving HE resistance can be summarized as follows:(1)reducing crystalline grain and inclusion sizes(oxides,sulfides,and titanium nitride),(2)controlling nano-precipitates(niobium carbide,titanium carbide,and composite precipitation),and(3)increasing residual austenite content under the reasonable tension strength of steel.

Molybdenum alloying in high-performance flat-rolled steel grades

Considerable progress in developing flat-rolled steel grades has been made by the Chinese steel industry over the recent two decades.The increasing demand for high-performance products to be used in infrastructural projects as well as in production of consumer and capital goods has been driving this development until today.The installation of state-of-the-art steel making and rolling facilities has provided the possibility of processing the most advanced steel grades.The production of high-performance steel grades relies on specific alloying elements of which molybdenum is one of the most powerful.China is nearly self-sufficient in molybdenum supplies.This paper highlights the potential and advantages of molybdenum alloying over the entire range of flat-rolled steel products.Specific aspects of steel property improvement with respect to particular applications are indicated.

Resonant tunneling in disordered borophene nanoribbons with line defects

Recently,borophene has attracted extensive interest as the wonder material,showing that line defects(LDs)occur widely at the interface between V_(1/5)and V_(1/6)boron sheets.Here,we study theoretically the electron transport through two-terminal disordered borophene nanoribbons(BNRs)with random distribution of LDs.Our results indicate that LDs strongly affect the electron transport properties of BNRs.Both V_(1/5)and V_(1/6)BNRs exhibit metallic behavior without any LD,in agreement with experiments.While in the presence of LDs,the overall electron transport ability is dramatically decreased,but some resonant peaks of conductance quantum are found in the transmission spectrum of any disordered BNR with arbitrary arrangement of LDs.These disordered BNRs exhibit metal-insulator transition with tunable transmission gap in the insulating regime.Furthermore,two evolution phenomena of resonant peaks are revealed for disordered BNRs with different widths.These results may help for understanding structure-property relationships and designing LD-based nanodevices.