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Transcatheter aortic valve implantation in a patient with anomalous right coronary artery originating from the left aortic sinus with interarterial course

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老年心脏病学杂志:英文版 2023年第8期20卷 612-614页

作者： Lu-Chen WANG yan-xiang liu Xiao-Gang SUN Wei WANG Department of Cardiovascular Surgery Fuwai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Recently,the utilization of transcatheter aortic valve implantation(TAVI)has gained increasing prevalence due to its expanding range of applications in managing symptomatic severe aortic stenosis(AS).Coronary obstruction,a life-threatening complication,has been reported to occur during and after TAVI at an incidence rate of 0.5%-1%.^([1])In addition to shallow sinus of Valsalva(less than 30 mm),low coronary take-off(below 12 mm from annulus plane),and calcification of native valve leaflets over the coronary ostium,anomalous origins of coronary arteries and compression from expanded transcatheter heart valve have been shown to cause TAVI-associated coronary occlusion.

关键词： coronary aortic implantation

Thermal fatigue and wear of compacted graphite iron brake discs with various thermomechanical properties

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China Foundry 2024年第3期21卷 248-256页

作者： Gui-quan Wang Zhuo Xu Zhong-li liu xiang Chen yan-xiang Li School of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake *** this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigated,aiming to provide an experimental foundation for achieving a balance between their thermal and mechanical *** graphite iron brake discs with different tensile strengths,macrohardnesses,specific heat capacities and thermal diffusion coefficients were produced by changing the proportion and strength of *** peak temperature,pressure load and friction coefficient of compacted graphite iron brake discs were analyzed through inertia friction *** morphology of thermal cracks and 3D profiles of the worn surfaces were also *** is found that the thermal fatigue of compacted graphite iron discs is determined by their thermal properties.A compacted graphite iron with the highest specific heat capacity and thermal diffusion coefficient exhibits optimal thermal fatigue *** of the matrix at low temperatures significantly weakens the function of alloy strengthening in hindering the propagation of thermal *** the reduced hardness,increasing the ferrite proportion can mitigate wear loss resulting from low disc temperatures and the absence of abrasive wear.

关键词： compacted graphite iron brake disc thermomechanical properties thermal fatigue wear

Dripping and evolution behavior of primary slag bearing TiO2 through the coke packed bed in a blast-furnace hearth

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International Journal of Minerals,Metallurgy and Materials 2017年第2期24卷 130-138页

作者： yan-xiang liu Jian-liang Zhang Zhi-yu Wang Ke-xin Jiao Guo-hua Zhang Kuo-chih Chou State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China Baogang Zhanjiang Iron and Steel Co. Ltd. Zhanjiang 524000 China

To investigate the flow of primary slag bearing TiO2 in the cohesive zone of blast furnaces, experiments were carded out based on the laboratory-scale packed bed systems. It is concluded that the initial temperature of slag dripping increases with decreasing FeO content and increasing TiO2 content. The slag holdup decreases when the FeO content is in the range of 5wt%-10wt%, whereas it increases when the FeO content exceeds 10wt% . Meanwhile, the slag holdup decreases when the TiO2 content increases from 5wt% to 10wt% but increases when the TiO2 content exceeds 10wt%. Moreover, slag/coke interface analysis shows that the reaction between FeO and TiO2 occurs be- tween the slag and the coke. The slag/coke interface is divided into three layers： slag layer, iron-rich layer, and coke layer. TiO2 in the slag is reduced by carbon, and the generated Ti diffuses into iron.

关键词： blast furnace slag titanium dioxide packed beds dripping

The Influence of Acid on the RockMechanical Characteristics of Deep Shale in theWujiaping Formation

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Energy Engineering 2024年第1期121卷 27-42页

作者： Hao Zhang yan Zhang Wei liu Ximin Zhang xiang liu School of Petroleum Engineering Yangtze UniversityWuhan430100China Petroleum Engineering Technology Research Institute Jianghan Oilfield Branch of SinopecWuhan430035China Drilling Technology Research Institute Sinopec Shengli Oilfield Service CorporationDeyang618000China

The microscopic characteristics and mechanical properties of rocks change after the action of acid on deep shale,which affects the fracturing ***,we designed and conducted indoor experiments related to the changes in macro and microscopic characteristics after the interaction of acid with the shale of Wujiaping Formation,based on which the characteristic law of fracture volume modification after acid fracturing was studied using numerical *** results demonstrate that the pores and fractures are enlarged and the structure is significantly loosened after the acid *** a 15%concentration of hydrochloric acid can effectively dissolve ***,the degree of acid-etching reaction is highly variable because of the different carbonate content,which reveals the strong inhomogeneity of the shale system in the Wujiaping Group reservoir *** the acid interacted with the shale rock samples,the triaxial compressive strength,elastic modulus,and Poisson’s ratio of shale ***,the evaluation of the effect after acid fracturing simulated by fracturing software revealed that the smaller the value of elastic modulus in shale-based reservoirs,the more favorable the fracture volume *** discovery not only provides a theoretical basis for the expansion and extension patterns of acid-fracturing in carbonaceous shale formations but also offers research methods and theoretical insights for the fundamental exploration of other deep-seated oil and gas resources.

关键词： Shale acid fracturing macro characteristics microscopic characteristics mechanical properties

A Novel Design of a Pre-separation Panel Structure to Protect Against the Impact of an Explosion in an Aircraft Plenum Chamber

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Acta Mechanica Solida Sinica 2024年第1期37卷 166-180页

作者： Zongxing liu xiang yang Jun liu School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China COMAC Shanghai Aircraft Design and Research Institute Shanghai 201210China

To reduce the damage of the pressurizing panel structure of a fuselage caused by an explosion at the“least risk bomb location”in an aircraft structure,a new pre-separation panel structure was designed to resist blast ***,the dynamic strain response and morphology of impact damage of the new pre-separation panel were measured in an impact damage ***,the commercial software LS-DYNA was used to calculate the propagation of the blast shock wave,and the results were compared with empirical equations to verify the rationality of the numerical calculation ***,the fluid–structure coupling method was used to calculate the damage process of the pre-separation panel structure under the impact of an explosion wave and an impact *** calculated results were in good agreement with the test results,which showed the rationality of the calculation method and the *** residual strength of the damaged pre-separation panel was significantly higher than that of the original damaged *** results show that the new pre-separation panel structure is reasonable and has certain significance for guiding the design of plenum chambers with strong resistance to implosion for aircraft fuselages.

关键词： Pre-separation panel structure Explosive response Residual strength Aircraft plenum chamber Least risk bomb location

Photocatalytic Site-Selective Cascade Radical Addition of Biaryl Ynones for the Construction of Spiro-and Fused Carbon Rings

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Chinese Journal of Chemistry 2024年第14期42卷 1599-1605页

作者： Kairui liu Chunhang Zhao Liji Gu xiang Li Jiali yan Siqi Lao Weiwei Huan yan Zhang Key Laboratory of the Ministry of Education for Advanced Catalysis Materials and Drug Discovery&Innovation CenterCollege of Chemistry and Materials ScienceZhejiang Normal UniversityJinhuaZhejiang321004 China Zhejiang Provincial Key Laboratory of Chemical Utilization of Forestry Biomass College of Chemistry and Materials EngineeringZhejiang A&F UniversityHangzhouZhejiang311300 China

Functionalized free radical addition/cyclization reactions represent an efficient way for introducing new functionality or coupling fragments to *** are good regional selectivity radical acceptors in organic synthesis,and many of bio-relevant cyclic compounds could be easily obtained by direct radical cyclization ***,we report a photocatalytic cascade radical addition of biaryl ynones,for the divergent synthesis of privileged carbon ***,further transformation of the multi-functional group product into a variety of other derivatives demonstrates the synthetic value of this developed method.

关键词： Ynones Photocatalysis Cascade cyclization Alkoxycarbonyl radical Dearomatization Biaryls Regioselectivity Radical reactions

Review of dynamics and active control of large-scale space membrane antenna

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Astrodynamics 2024年第1期8卷 1-26页

作者： xiang liu Guoping Cai Department of Engineering Mechanics MOE Key Laboratory of HydrodynamicsChongqing Research InstituteShanghai Jiao Tong UniversityShanghai200240China

Large-scale space membrane antennas have significant potential in satellite communication,space-based early warning,and Earth *** of their large size and high flexibility,the dynamic analysis and control of membrane antenna are *** maintain the working performance of the antenna,the pointing and surface accuracies must be strictly ***,the accurate dynamic modeling and effective active control of large-scale space membrane antennas have great theoretical significance and practical value,and have attracted considerable interest in recent *** paper reviews the dynamics and active control of large-scale space membrane ***,the development and status of large-scale space membrane antennas are ***,the key problems in the dynamics and active control of large membrane antennas,including the dynamics of wrinkled membranes,large-amplitude nonlinear vibration,nonlinear model reduction,rigid-flexible-thermal coupling dynamic modeling,on-orbit modal parameter identification,active vibration control,and wave-based vibration control,are discussed in ***,the research outlook and future trends are presented.

关键词： large-scale space membrane antenna dynamicmodeling active control

Older liver grafts from donation after circulatory death are associated with impaired survival and higher incidence of biliary non-anastomotic structure

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Hepatobiliary & Pancreatic Diseases International 2023年第6期22卷 577-583页

作者： Tian Shen Shan-Hua Zheng Jun Chen Zhi-Sheng Zhou Meng-Fan yang xiang-yan liu Jun-Li Chen Shu-Sen Zheng Xiao Xu Department of Hepatobiliary and Pancreatic Surgery Shulan(Hangzhou)HospitalHangzhou 310022China Division of Hepatobiliary Pancreatic Surgery The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China Key Laboratory of Integrated Oncology and Intelligent Medicine of Zhejiang Province Department of Hepatobiliary and Pancreatic SurgeryAffiliated Hangzhou First People’s HospitalZhejiang University School of MedicineHangzhou 310006China China Liver Transplant Registry Hangzhou 310003China NHC Key Laboratory of Combined Multi-organ Transplantation Hangzhou 310003China Institute of Organ Transplantation Zhejiang UniversityHangzhou 310003China

Background:Grafts from older donors after circulatory death were associated with inferior outcome in liver transplants in the *** it has seemed to remain controversial in the last decade,as a result of modified clinical protocols,selected recipients,and advanced technology of organ perfusion and *** present study aimed to examine the impact of older donor age on complications and survival of liver transplant using grafts from donation after circulatory death(DCD).Methods:A total of 944 patients who received DCD liver transplantation from 2015 to 2020 were included and divided into two groups:using graft from older donor(aged≥65 years,n=87)and younger donor(age<65 years,n=857).Propensity score matching(PSM)was applied to eliminate selection ***:A progressively increased proportion of liver transplants with grafts from older donors was observed from 1.68%to 15.44%during the study *** well-balanced older donor(n=79)and younger donor(n=79)were 1:1 *** were significantly more episodes of biliary nonanastomotic stricture(NAS)in the older donor group than the younger donor group[15/79(19.0%)vs.6/79(7.6%);P=0.017].The difference did not reach statistical significance regarding early allograft dysfunction(EAD)and primary non-function(PNF).Older livers had a trend toward inferior 1-,2-,3-year graft and overall survival compared with younger livers,but these differences were not statistically significant(63.1%,57.6%,57.6%vs.76.9%,70.2%,67.7%,P=0.112;64.4%,58.6%,58.6%vs.76.9%,72.2%,72.2%,P=0.064).The only risk factor for poor survival was ABO incompatible transplant(P=0.008)in the older donor *** the subgroup of ABO incompatible cases,it demonstrated a significant difference in the rate of NAS between the older donor group and the younger donor group[6/8(75.0%)vs.3/14(21.4%);P=0.014].Conclusions:Transplants with grafts from older donors(aged≥65 years)after circulatory death are more frequently associated with inferior outcome com

关键词： Older donor Liver transplantation Survival Biliary stricture Donation after circulatory death

Two-state energy model and experimental study of coal adsorb methane

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Journal of Coal Science & Engineering(China) 2013年第4期19卷 488-492页

作者： Zeng-Chao FENG Dong ZHAO Zhi-xiang liu yan-Qi WANG Hong-Qiang GOU Mining Technology Institute Taiyuan University of Technology Taiyuan 030024 China

There are two states of methane existing in coal, free methane and adsorptive methane. The two states of methane exchanged with each other which need the energy exchange with outside. It is released heat when methane adsorption on coal, instead of absorbed heat. According to the gas molecules Boltzmann energy distribution, is obtained the equilibrium equations of the two states of methane in coal, as well as the heat of adsorption equation when exchanged into each other. At the same time, high temperature experiments of methane adsorption on coal have been certificated to the theoretical model. At last the experimental results presented that： the two-state energy model could be accurately described the distribution of the two states of methane in the coal; the adsorption heat is related to the initial equilibrium state of methane adsorption; the adsorption heats are different with different coal ranks.

关键词： two-state energy model adsorption heat chemical potential experimental study