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多力场耦合条件下T型圆管通道内流体热混合机理研究

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西安交通大学学报 2025年第1期59卷 78-92页

作者：李桉琦苏博林梅王秋旺西安交通大学能源与动力工程学院西安710049

针对海洋动力平台和船舶动力装置中T型圆管通道内冷热流体间的热混合机理尚不清楚的问题,利用大涡模拟方法,对不同支管布置方式高温高压工况下(运行压力为10 MPa,进口流体温差为275 K,摇摆雷诺数为41 500)的多力场耦合T型圆管通道内流... 详细信息

针对海洋动力平台和船舶动力装置中T型圆管通道内冷热流体间的热混合机理尚不清楚的问题,利用大涡模拟方法,对不同支管布置方式高温高压工况下(运行压力为10 MPa,进口流体温差为275 K,摇摆雷诺数为41 500)的多力场耦合T型圆管通道内流体热混合机理进行数值研究。利用提出的混合系数定量评价了不同布置方式下T型圆管通道内流体混合效果,利用均方根温度定量评价了不同布置方式下T型圆管通道管壁处温度脉动情况。结果表明:剪切层和尾迹区内涡结构与温度场存在时间和空间上的协同机制,且涡脱落频率和温度脉动频率基本相同,脱落频率为19.3 Hz;附加惯性力引起T型圆管通道内涡结构和温度场在时间和空间上周期性变化,加速了流体混合过程,削弱了浮升力和重力引起的热分层现象,同时增大了流体域内温度波动,长度约为10.2 D(D为主管内径);与对应的静止工况相比,支管竖直向上、水平和竖直向下布置时,摇摆条件下混合系数分别增大了10.8%、18.3%和27.8%;摇摆条件竖直向下布置时,管壁处温度均方根峰值最大为0.16,约为静止工况的2倍。因此,支管竖直向上布置时,热混合效果最好,热分层现象最弱,在实际应用中应被优先考虑。

关键词： T型圆管通道浮升力摇摆条件热混合机理大涡模拟

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黔北正安地区安场向斜奥陶系五峰组—志留系龙马溪组页岩气富集规律

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岩性油气藏 2025年第1期37卷 182-193页

作者：吴松冯冰于继良蓝宝锋李龙王胜沈家宁李刚权贵州乌江能源投资有限公司贵州页岩气勘探开发有限责任公司贵州能源集团有限公司贵州能源产业研究院有限公司

四川盆地外缘黔北地区具有良好的页岩气勘探开发前景。基于测井、录井及分析化验等资料，对黔北正安地区安场向斜奥陶系五峰组—志留系龙马溪组页岩气储层特征及富集规律进行了分析。研究结果表明：（1）黔北正安地区安场向斜奥陶系五... 详细信息

四川盆地外缘黔北地区具有良好的页岩气勘探开发前景。基于测井、录井及分析化验等资料，对黔北正安地区安场向斜奥陶系五峰组—志留系龙马溪组页岩气储层特征及富集规律进行了分析。研究结果表明：（1）黔北正安地区安场向斜奥陶系五峰组—志留系龙马溪组岩性主要为硅质页岩与硅质岩，孔隙类型主要为有机孔隙及粒间孔、粒内溶孔、晶间孔等无机孔隙与页理缝和构造缝及微裂缝等。岩石中总有机碳（TOC）为0.34%～6.65%，平均为3.69%，纵向上自下而上总体呈先增大后减小的趋势，平面上在向斜核部的TOC含量较高，呈环带状向四周降低。岩心含气的质量体积为1.6～6.2 m3/t，平均为3.9 m3/t，龙马溪组总含气量垂向上随着深度的增加而增加，平面上从向斜中部向南北两端逐渐降低，从向斜核部向两翼逐渐降低。矿物脆性指数总体较高，具有很好的可压裂性。（2）研究区五峰组—龙马溪组为“陆棚边缘、改造残留、向斜浅埋”的独特地质背景，其有利的沉积环境及古生产力为页岩气富集成藏奠定了基础，良好的保存条件避免了页岩储层中天然气的大量逸散，上覆的新滩组盖层与下伏的宝塔组底板形成了“上盖下堵”的封堵组合。（3）盆外残余向斜页岩气在向斜中心明显富集，核部是页岩气聚集的有利位置，两翼低角度逆断层遮挡处也是页岩气的有利富集部位，微裂缝的发育有利于页岩气的聚集与稳产，因此中浅层残余向斜的井位部署应重点考虑“宽、缓、深”的核心部位。

关键词：页岩气储层特征脆性指数上盖下堵断层遮挡核部富集奥陶系五峰组—志留系龙马溪组安场向斜黔北地区

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Activation of immune signals during organ transplantation

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Signal Transduction and Targeted Therapy 2023年第4期8卷 1545-1570页

作者： Qingwen li Peixiang lan Institute of Organ Transplantation Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Key Laboratory of Organ Transplantation Ministry of EducationNHC Key Laboratory of Organ TransplantationKey Laboratory of Organ TransplantationChinese Academy of Medical SciencesWuhanChina

The activation of host’s innate and adaptive immune systems can lead to acute and chronic graft rejection,which seriously impacts graft ***,it is particularly significant to clarify the immune signals,which are critical to the initiation and maintenance of rejection generated after *** initiation of response to graft is dependent on sensing of danger and stranger *** ischemia and reperfusion of grafts lead to cell stress or death,followed by releasing a variety of damage-associated molecular patterns(DAMPs),which are recognized by pattern recognition receptors(PRRs)of host immune cells to activate intracellular immune signals and induce sterile *** addition to DAMPs,the graft exposed to‘non-self’antigens(stranger molecules)are recognized by the host immune system,stimulating a more intense immune response and further aggravating the graft *** polymorphism of MHC genes between different individuals is the key for host or donor immune cells to identify heterologous‘non-self’components in allogeneic and xenogeneic organ *** recognition of‘nonself’antigen by immune cells mediates the activation of immune signals between donor and host,resulting in adaptive memory immunity and innate trained immunity to the graft,which poses a challenge to the long-term survival of the *** review focuses on innate and adaptive immune cells receptor recognition of damage-associated molecular patterns,alloantigens and xenoantigens,which is described as danger model and stranger *** this review,we also discuss the innate trained immunity in organ transplantation.

关键词： immunity damage graft

Stability of Nonlinear Feedback Shift Registers with Periodic Input

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Computers, Materials & Continua 2020年第2期62卷 833-847页

作者： bo Gao Xuan liu Xiaobo Wu Shudong li Zhongzhou lan Hui Lu boyan liu 无 School of Computer Information Management Inner Mongolia University of Finance and EconomicsHoh-hot010051China Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou510006China School of Electrical and Electronic Engineering University of ManchesterManchester M139PLUK

The stability of Non-linear Feedback Shift Registers(NFSRs)plays an important role in the cryptographic *** to the complexity of nonlinear systems and the lack of efficient algebraic tools,the theorems related to the stability of NFSRs are still not *** this paper,we view the NFSR with periodic inputs as a boolean control *** on the mathematical tool of semi-tensor product(STP),the boolean network can be mapped into an algebraic *** these basic theories,we analyze the state space of non-autonomous NFSRs,and discuss the stability of an NFSR with periodic inputs of limited length or unlimited *** simulation results are provided to prove the efficiency of the *** on these works,we can provide a method to analyze the stability of the NFSR with periodic input,including limited length and unlimited *** this,we can efficiently reduce the computational complexity,and its efficiency is demonstrated by applying the theorem in simulations dealing with the stability of a non-autonomous NFSR.

关键词： Non-linear Feedback Shift Register(NFSR) boolean Network(BN) Semi-Tensor Product(STP) transition matrix stability periodic input

Pathogen profile and drug resistance analysis of spontaneous peritonitis in cirrhotic patients

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World Journal of Gastroenterology 2015年第36期21卷 10409-10417页

作者： Yong-Tao li Cheng-bo Yu Jian-Rong Huang Zheng-Ji Qin lan-Juan li State Key Laboratory for Diagnosis and Treatment of Infectious Diseases Collaborative Innovation Center for Diagnosis and Treatment of Infectious DiseasesThe First Affiliated HospitalCollege of MedicineZhejiang University Medical Statistics Office of Public Health Department Nantong University

AIM: To investigate the microbiological characteristics and drug resistance in liver cirrhosis patients with spontaneous ***: We analyzed the data of patients with liver cirrhosis and abdominal infection at the First Affiliated Hospital of Zhejiang University between January 2011 and December 2013. Pathogens present in the ascites were identified,and their sensitivity to various antibiotics was determined. RESULTS: We isolated 306 pathogenic bacteria from 288 cases: In 178 cases,the infection was caused by gram-negative strains(58.2%); in 85 cases,grampositive strains(27.8%); in 9 cases,fungi(2.9%); and in 16 cases,more than one pathogen. The main pathogens were Escherichia coli(E. coli)(24.2%),Klebsiella pneumoniae(18.9%),Enterococcus spp.(11.1%),and Staphylococcus aureus(7.5%). Of the 306 isolated pathogens,99 caused nosocomial infections and 207 caused community-acquired andother infections. The E. coli and K. pneumoniae strains produced more extended-spectrum β-lactamases in cases of nosocomial infections than non-nosocomial infections(62.5% vs 38%,P lin/tazobactam was significantly more effective against non-nosocomial E. coli infections(4% vs 20.8%,P liver cirrhosis are gram-negative,and drug resistance is significantly higher in nosocomial infections than in non-nosocomial infections.

关键词： liver cirrhosis Spontaneous peritonitis Drug sensi

Microstructural evolution and stress state related to mechanical properties of electron beam melted Ti-6Al-4V alloy modified by laser shock peening

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Journal of Materials Science & Technology 2020年第15期47卷 153-161页

作者： liang lan Xinyuan Jin Shuang Gao bo He Yonghua Rong Research Center of High-temperature Alloy Precision Forming School of Material EngineeringShanghai University of Engineering ScienceShanghai 201620China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

This work characterizes microstructural evolutions of electron beam melted(EBM) Ti-6 Al-4 V alloy modified via laser shock peening(LSP).The depth stress distribution and tensile properties of EBM Ti-6 Al-4 V alloy were measured before and after *** results indicate that microstructure consists of β phase with 7.2%±0.4% vol.% and balance α lamellar in EBM sample,and the α lamella was refined into nano-equiaxed grains and submicro-equiaxed grains after *** dominant refinement mechanism is revealed during *** faults were found in the LSP-treated sample,and their corresponding planes were determined as(0001) basal plane,(1010) prismatic plane,and(1011) pyramidal plane obtained by high resolution transmission electron *** subgrains and high-angle grains formed during dynamic recrystallization were identified by selected area electron diffraction *** LSP treatment produces a significantly residual compressive stress approximately-380 MPa with the depth of compressive stress layer reaching 450 μ*** and elongation of the EBM sample were significantly increased after *** strength and ductility enhancements are attributed to compre s sive stress,grain refinement and grain gradient distribution of α phase.

关键词： Electron beam melting Ti-6Al-4V alloy Laser shock peening Microstructural evolution Stress state Mechanical properties

Preparation and characterization of HMX/NH_(2)-GO composite with enhanced thermal safety and desensitization

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Defence Technology（防务技术） 2022年第11期18卷 2074-2082页

作者： Yu-lan Song Qi Huang bo Jin Ru-fang Peng State Key Laboratory of Environment-friendly Energy Materials School of Materials Science and EngineeringSouthwest University of Science and TechnologyMianyang621010China

To improve the safety of HMX,HMX/NH_(2)-GO composite was prepared with aqueous ammonia functionalized graphene oxide(NH_(2)-GO).The composite was characterized by SEM,Zeta potential,XPS,Raman spectrum,XRD,HPLC,DSC and BAM sensitivity *** results indicated that the functionalization with aqueous ammonia can enhance the interaction between GO and HMX,and more efficiently desensitize the *** optimal impact sensitivity of the HMX/NH_(2)-GO composite can be not less than 40 J,which is also the most insensitivity compared to the previous reports prepared by coating desensitization with non-energetic desensitized ***,the potential reason for the different impact and friction sensitivity was also discussed,which may bring a novel perspective to achieve the desensitization of energetic material.

关键词： HMX GO Ammonia Surface coating technology

Influence of multiple laser shock peening treatments on the microstructure and mechanical properties of Ti-6Al-4V alloy fabricated by electron beam melting

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International Journal of Minerals,Metallurgy and Materials 2022年第9期29卷 1780-1787页

作者： liang lan Ruyi Xin Xinyuan Jin Shuang Gao bo He School of Material Engineering Shanghai University of Engineering ScienceShanghai 201620China Research Center of High-temperature Alloy Precision Forming Shanghai University of Engineering ScienceShanghai 201620China

Laser shock peening(LSP)is an attractive post-processing method to tailor surface microstructure and enhance mechanical performances of additive manufactured(AM)*** effects of multiple LSP treatments on the microstructure and mechanical properties of Ti-6Al-4V part produced by electron beam melting(EBM),as a mature AM process,were studied in this ***,surface topography,residual stress,and tensile performance of EBM-manufactured Ti-6Al-4V specimens were systematically analyzed subjected to different LSP *** distribution of porosities in EBM sample was assessed via X-ray computed *** results showed that EBM samples with two LSP treatments possessed a lower porosity value of 0.05%compared to the value of 0.08%for the untreated *** strength of EBM samples with two LSP treatments was remarkably raised by 12%as compared with the as-built *** grains ofαphase were refined in near-surface layer,and a dramatic increase in the depth and magnitude of compressive residual stress(CRS)was achieved in EBM sample with multiple LSP *** grain refinement ofαphase and CRS with larger depth were responsible for the strength enhancement of EBM samples with two LSP treatments.

关键词： additive manufacturing laser shock peening electron beam melting residual stress Ti-6Al-4V alloy mechanical properties

Two new pseudo-isomeric nickel(Ⅱ)metal-organic frameworks with efficient electrocatalytic activity toward methanol oxidation

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Rare Metals 2021年第2期40卷 489-498页

作者： Shan liu Xiao Wang Hong-Guang Yu Ya-Pan Wu bo li Ya-Qian lan Tao Wu Jian Zhang Dong-Sheng li College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang443002China

Searching for non-noble metal catalysts with high activities and low price is critical to the commercialization of methanol oxidation in the process of fuel ***,two new pseudo-isomeric Ni metal-organic frameworks(Ni-MOFs)(CTGU-17/CTGU-18)have been prepared with 1,4-naphthalenedi-carboxylate(H_(2)NDC),4,4’-dipyridyl amine(DPA)and Ni(ClO_(4))_(2)under hydrothermal *** phase contains one water molecule,but differs dramatically in its bonding to the framework,resulting in different topological networks with fourfold interpenetrating 4-connected dia net(CTGU-17)and(3,7)-connected net(CTGU-18)and diverse electrocatalytic performance for methanol oxidation reaction(MOR).Remarkably,by combining each MOF with the conductive additive,acetylene black(AB),a composite material,AB&CTGU-18(2:4)was confirmed to have an excellent performance for MOR with a high mass specific peak current of 442.3 mA·mg^(-1).The enhanced electrocatalytic activities and robustness might be attributed to the synergetic effect of acetylene black and the active metal centers of MOFs particles for methanol *** present work would provide a new insight for the rational design of MOFs-based composites with enhanced methanol oxidation reaction performance.

关键词： Nickel(Ⅱ) MOFs Composite materials Electrocatalysis Methanol oxidation