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International Journal of Dermatology and Venereology 2024年第2期7卷 119-120页

作者： yu-kun zhao Hui-Hui Wu Juan-Hua Liu Di-Qing Luo Department of Dermatology The East Division of The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong 510700China

Introduction:Acrodermatitis continua of Hallopeau(ACH)is an uncommon chronic cutaneous *** to date,its treatment is still difficult and frustrating although various topical and systemic agents alone or in different combinations have been tried with variable ***,we report two cases of ACH successfully treated with calcipotriol/betamethasone *** presentation:Two cases of ACH were characterized by thumb involvement alone and showed an excellent response to calcipotriol/betamethasone ointment(1 g:calcipotriol 50µg and betamethasone 0.5 mg).Discussion:Treatment of ACH is challenging for *** systemic therapies and topical drugs have been applied,however,no universally effective treatment regimen has yet been established for long-lasting *** of calcipotriol and betamethasone is more effective in treating psoriasis than the individual components alone,and the current 2 cases with ACH were reported to be treated successfully by the calcipotriol/betamethasone ***:Topical calcipotriol/betamethasone compound is an optional agent for the treatment of ACH with a novel effect.

关键词： pustular eruptions calcipotriol/betamethasone ointment treatment

Treatment of coke plant wastewater by SND fixed biofilm hybrid system

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Journal of Environmental Sciences 2007年第2期19卷 153-159页

作者： QI Rong YANG kun yu zhao-xiang Department of Chemistry Tongji University Shanghai 200092 China

In this article, coke plant wastewater was treated by a simultaneous nitrifying and denitrifying （SND） fixed biofilm hybrid system. The results showed that suitable parameters of the system were important for the performance of the bio-degradation system. The chemical oxygen demand （COD） removal efficiency in this system was satisfactory, higher than 94%, and ammonia nitrogen was higher than 95%. The effluent COD concentration could meet the discharge standard, except for very few situations. The results showed that a sufficient carbon source was important for making ammonia nitrogen concentration meet the discharge standard. Then the TiN removal efficiency in this system can be brought higher than 94%. Dissolved oxygen （DO） is very important to the performance of the SND bio-degradation system, and the suitable DO is about 3.5-4.0 mg/L at the forepart of reactor. In addition, the performance of the system was almost not affected by pH value. The results show that the system is feasible to treat coke plant wastewater.

关键词： coke plant wastewater SND fixed biofilm ammonia nitrogen COD carbon source

Effect of Deep Cryogenic Treatment on Formation of Reversed Austenite in Super Martensitic Stainless Steel

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Journal of Iron and Steel Research International 2015年第5期22卷 451-456页

作者： Shi-qi ZHENG Wen JIANG Xuan BAI Shao-hong LI kun-yu zhao Xin-kun ZHU Department of Materials Science and Engineering Kunming University of Science and Technology

The effect of deep cryogenic treatment on the formation of reversed austenite （RA） in super martensitic stainless steel was investigated. RA was found to form in steels without （A） and with （B） deep cryogenic treatment. The volume fraction of RA initially increased and then decreased with increasing tempering temperature over 550-- 750 ℃ for the two steels, which were quenched at 1050 ℃. In addition, for both with and without deep cryogenic treatment, the RA content reached a maximum value at 650 ℃ although the RA content in steel B was greater than that in steel A over the entire range of tempering temperatures. Furthermore, the hardness （HRC） of steel B was greater than that of steel A at tempering temperatures of 550--750 ℃. From these results, the basic mechanism for the formation of RA in steels A and B was determined to be Ni diffusion. However, there were more Ni enriched points, a lower degree of enrichment, and a shorter diffusion path in steel B. It needed to be noted that the shapes of the RA consisted of blocks and stripes in both steels. These shapes resulted because the RA redissolved and trans- formed to martensite along the martensitic lath boundaries when the tempering temperature was 650--750 ℃, and a portion of RA in the martensitie lath divided the originally wider martensitic laths into a number of thinner ones. In- terestingly, the RA redissolved more rapidly in steel B and consequently resulted in a stronger refining effect.

关键词： reversed austenite super martensitie stainless steel deep cryogenic treatment diffusion transformation

Passivation Behaviors of Super Martensitic Stainless Steel in Weak Acidic and Weak Alkaline NaCl Solutions

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Journal of Iron and Steel Research International 2015年第12期22卷 1156-1163页

作者： Jian KANG Jun LI kun-yu zhao Xuan BAI Qi-long YONG Jie SU Institute of Materials Science and Engineering Kunming University of Science and Technology Institute of Structural Materials Central Iron and Steel Research Institute

The passivation behaviors of super martensitic stainless steels （SMSS） were studied by polarization curves at passive potential of -0.1 V and in various NaC1 solutions, electrochemical impedance spectroscopy （EIS） and X- ray photoelectron spectroscopy （XPS） analysis. Electrochemical test results showed that, in alkaline solutions, pas- sivation region width was wider, passivation current was smaller, and polarization resistance was greater~ thus, the passive film of SMSS in alkaline solutions had better passivation behaviors than that in acidic solutions. The polariza- tion curve and EIS of samples SMSS1 and SMSS2 were also used to study which sample had better passivation be- haviors. All results demonstrated that passive film structure of SMSS1 sample was more stable, and capacity of pas- sive film was enhanced. The impact of alloying elements on the passive film （SMSS） passivation capability was also discussed by XPS depth profiling, and XPS depth profiling showed that the composition of the passive film was mainly composed of Fe-oxide and Cr-oxide. So the passive film structures were mixed layers of Fe-oxide and Cr-ox- ide. Fe oxidation product and Cr oxidation product would help to improve the protective property of passive film, which could promote the formation of a passive film structure more stably and densely.

关键词： super martensitic stainless steel pH value polarization curve electrochemical impedance spectroscopy XPS depth profiling

Effect of deep cryogenic treatment on martensitic lath refinement and nano-twins formation of low carbon bearing steel

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Journal of Iron and Steel Research International 2020年第1期27卷 105-113页

作者： Xin-yang Lü Zhi-wei Wu Xiao He Jun Li Shao-hong Li Mao-sheng Yang kun-yu zhao Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunanChina Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The effect of heat treatment and deep cryogenic treatment on microstructural evolution of low carbon martensitic bearing steel was *** experimental results showed that the lath martensite was obtained by quenching and a few twins as substructures formed in some martensitic *** rudiment of sub-interfaces of martensitic lath was formed in the highdensity dislocation regions after deep cryogenic treatment;meanwhile,the number of twins increased,especially in the highdensity dislocation *** phenomenon is due to the increase in internal stress caused by cryogenic *** tempering,the rudiment of sub-interface further evolved into the martensitic lath boundary,and thus the original martensitic laths were *** twins formed by cryogenic treatment did not disappear after *** addition,small quantities of annealing twins formed in tempering *** laths morphology and substructures in different stages of the heat and deep cryogenic treatment were observed by tninsmission electron microscopy.

关键词： Low carbon bearing steel-Deep cryogenic treatment Internal stress Sub-interface Nano-twin

Carbides precipitation and their evolution of Cr15Co10Mo5-alloyed heat-resistant bearing steel after tempering at different temperatures

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Journal of Iron and Steel Research International 2019年第10期26卷 1096-1105页

作者： Mao-guo Xiao Xin-yang Lü Dong-hui Li Shao-hong Li kun-yu zhao Mao-sheng Yang School of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Institute for Special Steels Central Iron and Steel Research InstituteBeijing 100081China

The carbides precipitation and their evolution at elevated tempering temperature in Crl5Col0Mo5-alloyed heat-resistant bearing steel were investigated by means of the transmission electron *** results show that there is no carbide precipitated from the martensitic matrix when the sample was tempered at 480℃.However,when the sample was tempered at 540℃,a large number of stable spherical M6C carbides precipitated in the test ***,there are three types of carbides precipitated from the matrix including M6C,M2C and M23C6 carbides when the tempering temperature reached 600℃.The mechanical properties also present a correlation with the evolution of carbides during tempering at different *** indicates that the strengthening mechanism of the steel is mainly attributed to the precipitation of carbides and their evolution,including the morphologies and types of carbides at different *** addition,the austenitic layers with a thickness of about 30 nm have been obtained between the martensite laths after tempering at 600℃.The austenitic layers will produce transformation-induced plasticity effects to improve the toughness of the steel.

关键词： High-temperature bearing steel Carbide evolution Phase diagram Diffusion coefficient Secondary hardening Austenitic layer

Effects of traditional heat treatment and a novel deep cryogenic treatment on microstructure and mechanical properties of low-carbon high-alloy martensitic bearing steel

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Journal of Iron and Steel Research International 2021年第3期28卷 370-382页

作者： Dong-hui Li Wen-chao He Xu Zhang Mao-guo Xiao Shao-hong Li kun-yu zhao Mao-sheng Yang School of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093YunnanChina Institute for Special Steels Central Iron and Steel Research InstituteBeijing100081China

The effects of traditional heat treatment(quenching and then tempering)and deep cryogenic treatment on the microstructure and mechanical properties of a low-carbon high-alloy martensitic bearing steel were studied by Rockwell hardness test,X-ray diffractometry,scanning electron microscopy and transmission electron *** results show that the deep cryogenic treatment promotes the transformation of the retained austenite to martensite during cooling,which leads to the hardness of the sample after deep cryogenic treatment higher than that at the quenched ***,the carbon content in the martensite matrix after different treatments was calculated and the results indicated that deep cryogenic treatment can promote the segregation of carbon atoms in martensite to *** segregated carbon atoms act as and grow into nuclei for the formation of fine carbide particles during subsequent *** this resulted in the fact that the hardness of the tempered experimental steel after deep cryogenic treatment is higher than that without deep cryogenic treatment.

关键词： Heat treatment High-alloy martensitic bearing steel Deep cryogenic treatment Carbide Retained austenite

A modified 3D mean strain energy density criterion for predicting shale mixed-mode Ⅰ/Ⅲ fracture toughness

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2411-2428页

作者： kun Zheng Chaolin Wang yu zhao Jing Bi Haifeng Liu College of Civil Engineering Guizhou UniversityGuiyang550025China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic *** edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi *** theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture *** distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is *** the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is *** results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar *** macroscopic fracture signatures are consistent with those of triaxial hydraulic *** average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than *** to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods.

关键词： Longmaxi shale Hydraulic fracturing Fracture mechanisms Fracture criteria Mixed-modeⅠ/Ⅲfracture toughness Edge-notched disk bending

Facile preparation and efficient MnxCoy porous nanosheets for the sustainable catalytic process of soot

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Green Energy & Environment 2024年第3期9卷 516-528页

作者： Miaomiao Hu kun Zhou Tingyi zhao Zheng Li Xianhai Zeng Di yu Xuehua yu Mingqin zhao Zhihui Shao Qixiang Xu Bing Cui Flavors and Fragrance Engineering&Technology Research Center of Henan Province College of Tobacco ScienceHenan Agricultural UniversityZhengzhou450002China School of Ecology and Environment Zhengzhou UniversityZhengzhou450001China College of Energy Xiamen UniversityXiamen361102China College of Chemistry and Chemical Engineering Shenyang Normal UniversityShenyang110034China

The pursuit of high-performance is worth considerable effort in catalysis for energy efficiency and environmental sustainability. To develop redox catalysts with superior performance for soot combustion, a series of Mn_(x)Co_(y) oxides were synthesized using MgO template *** method greatly improves the preparation and catalytic efficiency and is more in line with the current theme of green catalysts and sustainable development. The resulting Mn_(1)Co_(2.3) has a strong activation capability of gaseous oxygen due to a high concentration of Co^(3+) and Mn^(3+). The Mn doping enhanced the intrinsic activity by prompting oxygen vacancy formation and gaseous oxygen adsorption. The nanosheet morphology with abundant mesoporous significantly increased the solid–solid contact efficiency and improved the adsorption capability of gaseous reactants. The novel design of Mn_(1)Co_(2.3)oxide enhanced its catalytic performance through a synergistic effect of Mn doping and the porous nanosheet morphology, showing significant potential for the preparation of high-performance soot combustion catalysts.

关键词： Soot combustion Intrinsic activity Contact efficiency Mn doping DFT

Adaptive Consensus of Uncertain Multi-Agent Systems With Unified Prescribed Performance

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1310-1312页

作者： kun Li Kai zhao Yongduan Song The authors are with the School of Automation Chongqing UniversityChongqing 400044China

Dear Editor,An adaptive consensus control algorithm for uncertain multi-agent systems(MAS),capable of guaranteeing unified prescribed performance,is presented in this *** many existing prescribed performance related works,the developed control exhibits some ***,a distributed prescribed time observer is introduced so that not only each follower is able to estimate the leader’s signal within a predetermined time,but also the control design for each agent is independent with its neighbors.

关键词： agent prescribed Uncertain