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Journal of Materials Science & Technology 2014年第12期30卷 1181-1192页

作者： Zhiming Zhang Jianqiu Wang En-Hou Han Wei Ke Key Laboratory of Nuclear Materials and safety assessment Liaoning Key Laboratory for Safety and Assessment Technique of Nuclear Materials Institute of Metal Research Chinese Academy of Sciences

Oxidation of Alloy 690 TT samples either manually ground to 400 and 1500 grit, mechanically polished, or electropolished was performed in a solution of 1500 10 6B and 2.3 10 6Li with 2.5 10 6dissolved H2, at 325℃ and 15.6 MPa for 60 days. The oxide films grown on samples with different surface states were analyzed using various techniques. Results show that a triple-layered structure was formed after immersion： an outermost layer with large scattered oxide particles rich in Fe and Ni, an intermediate layer with small compact oxide particles rich in Cr and Fe for the ground surfaces and loose needle-like oxides rich in Ni for the polished surfaces, and an inner layer with continuous Cr-rich oxides. The surface state was found to affect not only the surface morphology, but also the corrosion rate. Grinding accelerated the growth of protective oxide films such that the ground samples showed a lower oxidation rate than the polished *** of ground Alloy 690 TT showed superior resistance to intergranular attack（IGA）.

关键词： Alloy 690TT Oxidation Surface states High pressure and high temperature

Oxidation and Electrochemical Behavior of MonolayerGraphene-Coated Copper in Simulated Primary Water

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 89-93页

作者： Hong-Liang Ming Si-Yan Wang Zhi-Ming Zhang Jian-Qiu Wang En-Hou Han Wei Ke Key Laboratory of Nuclear Materials and safety assessment Liaoning Key Laboratory for Safety and Assessment Technique of Nuclear MaterialsInstitute of Metal ResearchChinese Academy of Sciences

In high-temperature and high-pressure water, traditional anticorrosion approaches are not suitable to be used to protect structural materials from oxidation and corrosion. In this study, monolayer graphene was explored as a barrier to protect the materials from degradation. The oxidation and corrosion rate of the monolayer-graphene-coated copper is much lower than that of the bare copper, suggesting that the monolayer graphene can effectively protect the copper from oxidation and corrosion in the simulated primary water of pressurized water reactors.

关键词： Monolayer graphene Oxidation behavior Electrochemical behavior Simulated primarywater

Transferred Monolayer Graphene as a Potential Anti-Oxidation Barrier for Alloy 690TT in Simulated Primary Water

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Journal of Materials Science & Technology 2015年第12期31卷 1171-1174页

作者： Hongliang Ming Siyan Wang Zhiming Zhang Jianqiu Wang En-Hou Han Wei Ke Key Laboratory of Nuclear Materials and safety assessment Liaoning Key Laboratory for Safety and Assessment Technique of Nuclear MaterialsInstitute of Metal ResearchChinese Academy of Sciences

To explore the usage of monolayer graphene as an anti-oxidation barrier in simulated primary water of pressurized water reactors（PWRs）,we transferred the monolayer graphene synthesized by low pressure chemical vapor deposition（LPCVD） on Cu foil to Alloy 690 *** a 500 h immersion,strong oxidation resistance was obtained from the graphene coated Alloy 690 TT sample,indicating that the transferred monolayer graphene can act as an effective barrier to protect the substrate from oxidation in simulated primary water of PWRs.

关键词： Graphene Oxidation 690TT Simulated primary water

Vertical load capacities of roof truss cross members

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International Journal of Mining Science and Technology 2016年第3期26卷 517-520页

作者： Gearhart David F. Mohamed Khaled Morsy office of Mine safety & Health research National Institute for Occupational Safety & Health

Trusses used for roof support in coal mines are constructed of two grouted bolts installed at opposing forty-five degree angles into the roof and a cross member that ties the angled bolts together. The load on the cross member is vertical, which is transverse to the longitudinal axis, and therefore the cross member is loaded in the weakest direction. Laboratory tests were conducted to determine the vertical load capacity and deflection of three different types of cross members. Single-point load tests, with the load applied in the center of the specimen and double-point load tests, with a span of 2.4 m, were conducted. For the single-point load configuration, the yield of the 25 mm solid bar cross member was nominally 98 kN of vertical load, achieved at 42 cm of deflection. For cable cross members, yield was not achieved even after 45 cm of deflection. Peak vertical loads were about 89 kN for 17 mm cables and67 kN for the 15 mm cables. For the double-point load configurations, the 25 mm solid bar cross members yielded at 150 kN of vertical load and 25 cm of deflection. At 25 cm of deflection individual cable strands started breaking at 133 and 111 kN of vertical load for the 17 and 15 mm cable cross members respectively.

关键词： Roof truss Coal mining Ground control Load capacity Roof support

Pitting corrosion of a Rare Earth Mg alloy GW93

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Journal of Materials Science & Technology 2017年第9期33卷 954-960页

作者： Yingwei Song Dayong Shan En-Hou Han Key Laboratory of Nuclear Materials and safety assessment Institute of Metal ResearchChinese Academy of Sciences

Pitting corrosion of magnesium(Mg) alloys is greatly associated with their microstructure, especially second phases. The second phases in traditional Mg alloys such as AZ91 are electrochemically nobler than Mg matrix, while the second phases in Rare earth(RE) Mg alloy GW93 are more active than Mg matrix. As a result, the pitting corrosion mechanism of Mg alloy GW93 is different from the traditional ones. This paper aims to clarify the pitting corrosion mechanism of Mg alloy GW93 through the studies of Volta potential by Scanning Kelvin Probe Force Microscopy(SKPFM), corrosion morphology by Scanning Electron Microscope(SEM), and corrosion resistance by electrochemical tests. Results reveal that the pitting corrosion of GW93 includes three stages, first, dissolution of the second phases, followed by corrosion of Mg matrix adjacent to the dissolved second phases, and finally, propagation of corrosion pits along the depth direction of the dissolved second phases. Anodic second phases and enrichment of Clin the thick corrosion product films dominate the propagation of pitting corrosion.

关键词： Mg alloys Pitting corrosion Second phases Oxide films

Analysis of the design and performance characteristics of pumpable roof supports

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International Journal of Mining Science and Technology 2017年第1期27卷 91-99页

作者： Batchler Timothy NIOSH Office of Mine Safety and Health ResearchPittsburghPA 15236USA

Pumpable roof supports are currently being used to provide a safe working environment for longwall mining. Because different pumpable supports are visually similar and installed fundamentally in the same manner as other supports, there is a tendency to believe they all perform the same way. However, there are several design parameters that can affect their performance, including the cementitious material properties and the bag construction practices that influence the degree of confinement provided. A full understanding of the impact of these design parameters is necessary to optimize the support application and to provide a foundation for making further improvements in the support performance. This paper evaluates the impact of various support design parameters by examining full-scale performance tests conducted using the National Institute for Occupational safety and Health(NIOSH) Mine Roof Simulator(MRS) as part of manufacturers' developmental and quality control testing. These tests were analyzed to identify correlations between the support design parameters and the resulting performance. Based on more than 160 tests over 7 years, quantifiable patterns were examined to assess the correlation between the support dimensions, cementitious material type, wire pitch, and single-wall vs. dualwalled bag designs to the support capacity, stiffness, load shedding events, and yield characteristics.

关键词： Pumpable Roofsuppo Performance characteristics Secondary support

Influence of Conductivity on Corrosion Behavior of 304 Stainless Steel in High Temperature Aqueous Environment

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Journal of Materials Science & Technology 2016年第4期32卷 333-340页

作者： Jiazhen Wang Jianqiu Wang En-Hou Han Key Laboratory of Nuclear Materials and safety assessment Institute of Metal Research Chinese Academy of Sciences

The influence of conductivity on corrosion behavior of 304 stainless steel （SS） in high temperature water was investigated by using in-situ potentiodynamic polarization curves, electrochemical impedance spectra （EIS） at 300 ℃, and ex-situ scanning electron microscopy （SEM）, X-ray diffraction （XRD）, and X-ray pho- toelectron spectroscopy （XPS）. The structures of oxide films formed on 304 SS change with different conductivities at 300 ℃. With the increase in conductivity, the passive current density increases while the resistances of oxide films decrease. But the resistances do not decrease lineally with the increase in conductivity. A modified double-layer model for oxide structure was proposed to explain the influence mechanism of conductivity on the oxide films on 304 SS in high temperature water. Improving the 10B enrichment level can reduce the conductivity of primary water and increase the corrosion resistance of 304 SS.

关键词： Stainless steelPolarizationElectrochemical impedance spectraHigh temperature corrosion

Characteristics of Oxidation and Oxygen Penetration of Alloy 690 in 600°C Aerated Supercritical Water

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Journal of Materials Science & Technology 2018年第3期34卷 561-569页

作者： Xiangyu Zhong Xinqiang Wu En-Hou Han CAS Key Laboratory of Nuclear Materials and safety assessment Liaoning Key Laboratory for Safety and Assessment Technique of Nuclear MaterialsInstitute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The oxide films formed on Alloy 690 exposed to 600 ℃ supercritical water were characterized using mass measurement, X-ray diffraction. Raman spectroscopy, scanning electron microscopy equipped with energy dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. It was found that the mass gain of the alloy in supercritical water decreased with increasing exposure time. The oxide films have a double-layer structure, with an inner layer rich in Cr and outer layer rich in Ni and Fe after short time and long time exposure. The penetration of the oxide along the grain boundaries was observed, and the penetration depth increased with increasing exposure time. The grain boundaries and voids are the short-path of oxygen diffusion into the metal.

关键词： Ni-based alloy XPS Supercritical water High temperature corrosion High temperature oxidation Oxide film

Influence of Ethanolamine on Corrosion of Alloy 690 in Simulated Secondary Water

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Journal of Materials Science & Technology 2015年第10期31卷 1039-1046页

作者： Jiazhen Wang Jianqiu Wang Key Laboratory of Nuclear Materials and safety assessment Institute of Metal ResearchChinese Academy of Sciences

Effect of ethanolamine （ETA） on Alloy 690 in simulated pressurized water reactor （PWR） secondary cooling water was studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polarization, atomic force microscopy （AFM）, Fourier transform infrared spectroscopy-attenuated total reflectance （FTIR-ATR）, X-ray photoelectron spectrometer （XPS） and time of flight secondary ion mass spectrometry （ToF-SIMS）. The results show that moderate addition of ETA can enhance the corrosion resistance of Alloy 690 in high-temperature pressurized water and the optimum additive value is 2 mg/L. The addition of ETA contributes to the formation of oxide rather than hydroxide in the film on the surface of Alloy 690. The corrosion resistance of Alloy 690 at 320 ℃ with the addition of ETA is better than that at 280 ℃.

关键词： Ethanolamine (ETA)Alloy 690High-temperature electrochemistry Oxide film

Who will carry out the tests that would be necessary for proper safety evaluation of food emulsifiers?

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Food Science and Human Wellness 2019年第2期8卷 126-135页

作者： Katalin FCsáki∗ Éva Sebestyén National Food Chain safety office Directorate for Food Safety Risk AssessmentPO BOX 407H-1537 BudapestHungary

Surfactant food emulsifiers are among the most extensively used food *** all authorized food additives,emulsifiers have been evaluated by risk assessors,who consider them as ***,there are growing concerns among scientists about their possible harmful effects on intestinal barriers and *** is also suggested that emulsifier consumption might be one of the main causes of the rising incidence of a number of diseases,such as allergic diseases,celiac disease,type I diabetes and Crohn’s ***,it has recently been suggested that emulsifier consumption might contribute to the development of metabolic syndrome and can promote colitis-associated colorectal cancer *** paper provides an overview of the current scientific knowledge on possible effects of surfactant emulsifiers on intestinal barriers and also of regulatory risk assessment *** main objective is to reveal the reasons for the discrepancies between the opinions of risk assessors and the scientific *** would like to draw the attention of the academic world to the need of specific in vivo and/or clinical studies for each emulsifier in order to help risk assessors make adequate evaluations and rule out with certainty that authorized food emulsifiers pose a safety concern to consumers’health.

关键词： Food emulsifiers Surfactants Intestinal barriers Crohn’s diseases Microbiota Risk assessment EFSA