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Journal of Iron and Steel Research International 2015年第6期22卷 527-533页

作者： Shuai YANG Yun PENG xiao-mu zhang Zhi-ling TIAN China Railway Materials Technologies Company Limited State Key Laboratory of Advanced Steel Processes and Products Central Iron and Steel Research Institute

The influence of aging temperature on phase transformation and mechanical properties of weld metal of maraging steel （grade C300） was studied. Microstructure was analyzed by means of optical microscopy, transmission e leetron microscopy, scanning electron microscopy and energy dispersive spectrum analysis. Gibbs free energy of Nia Ti and Fez Mo at different temperature was calculated by Thermal-calc software. The microstructure of weld metal in as- welded state is martensite. The yield strength of weld metal after 430 ℃ aging process may increase to 1561 MPa from 890 MPa in as-welded state, which is ascribed to the formation of spinodal constitute and GP zones. After 480 ℃ aging process, there are great deal of NiaTi precipitates in the martensite matrix and 10% reverted austenite phase in the cellular grain boundary, and the yield strength increases to 1 801 MPa. After aging process at 580 ℃ , there are many Fe2 Mo precipitates in the martensite matrix and 30%o reverted austenite phase in the cellular grain boundary, and the yield strength is 1329 MPa, which ls the lowest among the three cases. The phase transformation may also influence the toughness. It is found that precipitates make the toughness decrease and reverted austenite increases it. The mechanism of phase transformation on strength and toughness is discussed.

关键词： maraging steell weld metal aging temperature precipitate reverted austenitel mechanical property

Microstructure and Mechanical Properties of GMAW Weld Metal of 890MPa Class Steel

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Journal of Iron and Steel Research International 2014年第5期21卷 539-544页

作者： Yun PENG Xing-na PENG xiao-mu zhang Zhi-ling TIAN Tao WANG State Key Laboratory of Advanced Steel Processes and Products Central Iron and Steel Research Institute Beijing Institute of Structure and Environment Engineering

The relationship between microstructure and mechanical properties of gas metal arc weld metal with strength over 890 MPa is discussed. The microstructure of the weld metals is characterized with OM, SEM, TEM and EBSD. The microstructure of the weld metals is mainly composed of martensite and bainite. Experimental results show that the microstructure with predominant fine lath bainite possesses good toughness of 77 .l, while its yield strength is less than 800 MPa. The microstructure of coarse lath martensite and bainite has the lowest toughness of 43 J and its yield strength is 820 MPa. The mixed microstructure with fine martensite, bainite and retained austenite films bears good combination of toughness and yield strength （62 J and 880 MPa, respectively）. It is concluded that fine effective grain size and ductile phase of austenite films are two main factors to achieve good mechanical properties.

关键词： high strength steel weld metal microstructure mechanical property

Relapse of acute lymphoblastic leukemia in the pancreas after allogeneic bone marrow transplantation

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Chinese Medical Journal 2010年第22期123卷 3364-3366页

作者： ZHAO xiao-mu zhang Zhong-tao LI Jian-she HAN Wei Department of General Surgery Beijing Friendship Hospital Capital Medical University Beijing 100050 China

The occurrence of metastatic lesions in the pancreas of patients with cancer, including hematological cancers,is uncommon （1.6%-37.5%） and of these, the majority of patients will have widespread disease.1-7 Isolated potentially resectable pancreatic metastases are rarely seen. Resection of metastatic tumors of the pancreas has been reported, but its role in improving survival rates or quality of life is not clear.7,8 However,

关键词： pancreas acute leukemia relapse allogeneic bone marrow transplantation

Insulin autoantibodies,D-dimer and microalbuminuria:A crosssectional,case-control study of type 2 diabetes

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World Journal of Diabetes 2025年第2期16卷 38-46页

作者： Lin-Shan zhang Peng Yu Fei Yao Zhi-Qiang Lu xiao-mu Li Hong Chen Department of Endocrinology Zhongshan HospitalFudan UniversityShanghai 200032China Department of Endocrinology Shanghai Geriatric Medical CenterShanghai 201104China Department of Endocrinology Fuzhou Hospital of Traditional Chinese MedicineFuzhou 350000Fujian ProvinceChina

BACKGROUND Type 2 diabetes mellitus(T2DM)often leads to vascular complications,such as *** role of insulin autoantibodies(IAA)and their interaction with D-dimer in this context remains *** To investigate the characteristics of IAA and its effect on albuminuria in T2DM *** We retrospectively analyzed clinical data from 115 T2DM patients with positive IAA induced by exogenous insulin,and 115 age-and sex-matched IAA-negative T2DM patients as *** scores were calculated using multivariate logistic *** variables were selected using the least absolute shrinkage and selection operator(LASSO)*** constructed a prediction model and analyzed the association between IAA and albuminuria based on demographic and laboratory *** The IAA-positive group had significantly higher D-dimer levels[0.30(0.19-0.55)mg/L vs 0.21(0.19-0.33)mg/L,P=0.008]and plasma insulin levels[39.1(12.0-102.7)μU/mL vs 9.8(5.5-17.6)μU/mL,P0.5 g/L)was 2.88(95%confidence interval:1.17-7.07)in the IAA-positive group(P interaction<0.05).CONCLUSION D-dimer elevation is an independent risk factor for abnormal albuminuria and interacts with IAA in the development of abnormal albuminuria in T2DM patients.

关键词： Insulin autoantibody Microalbuminuria D-dimer Type 2 diabetes

Gas-Solid Flow,Combustion Characteristics,and Gas Emissions in a 75 t/h CFB Boiler Based on the CPFD Method

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Journal of Thermal Science 2025年第1期34卷 323-336页

作者： HUANG Xiankun BAI zhang ZHU xiaoli WANG Shuoshuo mu Lin GONG Liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of TechnologyDalian 116024China

A 3D simulation using Computational Particle Fluid Dynamics(CPFD)methods was used to calculate coal combustion in a 75 t/h industrial-scale circulating fluidized bed(CFB)*** characteristics,gas-solid flow characteristics,and gaseous pollutant emissions of CFB boilers from combustion ignition to stable operation were systematically evaluated in this *** show that the temperature distribution is relatively uniform throughout the *** the combustion process unfolds within the boiler,the gas composition curve strikingly portrays the inverse correlation between CO_(2)and O_(2)*** the combustion reaction progresses,it becomes evident that the concentration of CO_(2)progressively increases,while the concentration of O_(2)concurrently *** inverse relationship underscores the fundamental combustion reaction,where carbon-based fuels react with oxygen to produce carbon dioxide and release ***,a comprehensive analysis has revealed that,from ignition to stable combustion,both nitric oxide(NO)and sulfur dioxide(SO_(2))emissions exhibit a declining *** reduction in pollutant generation is attributed to the improvement in combustion *** complete combustion leads to lower levels of unburned hydrocarbons,which are prone to NO ***,the sulfur content in the fuel is more efficiently oxidized to sulfur trioxide(SO_(3))or bound in sulfates,reducing SO_(2)*** steady state in the simulation,the SO_(2)mass flow rate varies significantly with the furnace height,gradually increasing from 0.07 kg·s^(-1)at 4 m at the bottom of the furnace to a peak of 0.078 kg·s^(-1)at 8 m in the center,and then decreasing to 0.06 kg·s^(-1)at 20m at the top of the furnace.

关键词： circulating fluidized bed particle flow combustion CPFD modeling

Antibiotic exposure alters the honeybee gut microbiota and may interfere with the honeybee behavioral caste transition

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INSECT SCIENCE 2025年第1期32卷 260-276页

作者： zhang, Zijing mu, xiaohuan Cao, Qina Zhai, Yifan Zheng, Li Liu, Yan Zheng, Hao zhang, Xue Hebei Normal Univ Coll Life Sci Hebei Collaborat Innovat Ctr Ecoenvironm Hebei Key Lab Anim Physiol Biochem & Mol Biol Shijiazhuang Peoples R China China Agr Univ Coll Food Sci & Nutr Engn Beijing Peoples R China Shandong Acad Agr Sci Inst Plant Protect Jinan Peoples R China Minist Agr & Rural Affairs Key Lab Nat Enemies Insects Jinan Peoples R China China Agr Univ Coll Plant Protect Dept Entomol Beijing Peoples R China

Behavioral division is essential for the sustainability and reproduction of honeybee populations. While accumulating evidence has documented that antibiotic exposure interferes with bee behavioral divisions, how the gut microbiome, host physiology, and genetic regulation are implicated in this process remains understudied. Here, by constructing single-cohort colonies, we validated that the gut microbiota varied in composition between age-matched nurse and forager bees. Perturbing the gut microbiota with a low dose of antibiotic retained the gut bacterial size, but the structure of the microbial community continuously diverged from the control group after antibiotic treatment. Fewer foragers were observed in the antibiotic groups in the field experiment. A combinatorial effect of decreased gut metabolic gene repertoires, reduced brain neurotransmitter titers, and downregulated brain immune genes could potentially be related to behavioral tasks transition delay. This work indicates that the disturbance to both the gut microbiome and host physiologies after antibiotic exposure may have implications on social behavior development, highlighting the need for further research focusing on antibiotic pollution threatening the honeybee population's health.

关键词： antibiotic resistance Apis mellifera behavioral development immune genes

Optimization of production well patterns for natural gas hydrate reservoir: Referring to the results from production tests and numerical simulations

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China Geology 2025年第1期8卷 39-57页

作者： Lang-feng mu Hao-tian Liu Chi zhang Yi zhang Hai-long Lu School of Earth and Space Sciences Peking UniversityBeijing 100871China Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing 100871China Chinese Academy of Geological Sciences China Geological SurveyMinistry of Natural Resources Beijing 100037China College of Engineering Peking UniversityBeijing 100871China National Engineering Research Center of Natural Gas Hydrate Exploration and Development Guangzhou 511458China China National Oil and Gas Exploration and Development LTD Corporation Petro-ChinaBeijing 100034China

Natural gas hydrate is a clean energy source with substantial resource *** contrast to conventional oil and gas,natural gas hydrate exists as a multi-phase system consisting of solids,liquids,and gases,which presents unique challenges and complicates the mechanisms of seepage and *** domestic and international natural gas hydrate production tests typically employ a single-well production *** this approach has seen some success,it continues to be hindered by low production rates and short production ***,there is an urgent need to explore a new well network to significantly increase the production of a single *** paper provides a comprehensive review of the latest advancements in natural gas hydrate research,including both laboratory studies and field *** further examines the gas production processes and development outcomes for single wells,dual wells,multi-branch wells,and multi-well systems under conditions of depressurization,thermal injection,and CO_(2) *** this basis,well types and well networks suitable for commercial exploitation of natural gas hydrate were explored,and the technical direction of natural gas hydrate development was *** study shows that fully exploiting the flexibility of complex structural wells and designing a well network compatible with the reservoir is the key to improving production from a single ***,multi-well joint exploitation is identified as an effective strategy for achieving large-scale,efficient development of natural gas hydrate.

关键词： Gas Hydrate Production Depressurization Heat Injection Replacement multi-Branch Well Well patterns Hydrate exploration engineering

Data-Driven Method for Predicting Remaining Useful Life of Bearings Based on multi-Layer Perception Neural Network and Bidirectional Long Short-Term Memory Network

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Structural Durability & Health Monitoring 2025年第2期19卷 365-383页

作者： Yongfeng Tai Xingyu Yan Xiangyi Geng Lin mu Mingshun Jiang Faye zhang CRRC Qingdao Sifang Co. Ltd.Qingdao266111China School of Control Science and Engineering Shandong UniversityJinan250061China Public(Innovation)Experimental Teaching Center Shangdong UniversityQingdao266237China Engineering Training Center Shangdong UniversityJinan250061China

The remaining useful life prediction of rolling bearing is vital in safety and reliability *** engineering scenarios,only a small amount of bearing performance degradation data can be obtained through accelerated life *** the absence of lifetime data,the hidden long-term correlation between performance degradation data is challenging to mine effectively,which is the main factor that restricts the prediction precision and engineering application of the residual life prediction *** address this problem,a novel method based on the multi-layer perception neural network and bidirectional long short-term memory network is ***,a nonlinear health indicator(HI)calculation method based on kernel principal component analysis(KPCA)and exponential weighted moving average(EWMA)is ***,using the raw vibration data and HI,a multi-layer perceptron(MLP)neural network is trained to further calculate the HI of the online bearing in real ***,The bidirectional long short-term memory model(BiLSTM)optimized by particle swarm optimization(PSO)is used to mine the time series features of HI and predict the remaining service *** verification experiments and comparative experiments are carried out on the XJTU-SY bearing open *** research results indicate that this method has an excellent ability to predict future HI and remaining life.

关键词： Remaining useful life prediction rolling bearing health indicator construction multilayer perceptron bidirectional long short-term memory network

内踝上逆行岛状筋膜皮瓣修复足踝部皮肤软组织缺损

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中南大学学报（医学版） 2007年第4期32卷 710-712页

作者：肖目张龙剑虹黄晓元中南大学湘雅医院烧伤整形科长沙410008

目的:探讨足踝部皮肤软组织缺损并骨外露或跟腱外露的修复方法。方法:应用内踝上逆行岛状筋膜皮瓣转移修复13例由车祸外伤、疤痕溃疡、肿瘤等所致的足踝部皮肤软组织缺损并骨外露或跟腱外露。修复皮肤软组织缺损最大面积6cm×14cm,跟骨... 详细信息

目的:探讨足踝部皮肤软组织缺损并骨外露或跟腱外露的修复方法。方法:应用内踝上逆行岛状筋膜皮瓣转移修复13例由车祸外伤、疤痕溃疡、肿瘤等所致的足踝部皮肤软组织缺损并骨外露或跟腱外露。修复皮肤软组织缺损最大面积6cm×14cm,跟骨外露最大面积5cm×10cm。结果:共切取内踝上逆行岛状筋膜皮瓣13块,其中1例岛状筋膜皮瓣术后坏死,行游离背阔肌肌皮瓣移植修复愈合,其余内踝上逆行岛状筋膜皮瓣及供瓣区所植皮片均完全成活,术后随访6月～4年,效果满意。结论:内踝上逆行岛状筋膜皮瓣移植是修复足踝部皮肤软组织缺损并骨外露或跟腱外露的理想方法之一。

关键词：逆行岛状筋膜皮瓣移植修复足踝部软组织缺损皮肤

Barrierless reactions of C2 Criegee intermediates with H_(2)SO_(4)and their implication to oligomers and new particle formation

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Journal of Environmental Sciences 2025年第3期149卷 574-584页

作者： Yang Cheng Chao Ding Tianlei zhang Rui Wang Ruxue mu Zeyao Li Rongrong Li Juan Shi Chongqin Zhu Institute of Theoretical and Computational Chemistry Shaanxi Key Laboratory of CatalysisSchool of Chemical&Environment ScienceShaanxi University of TechnologyHanzhongShaanxi 723001China College of Chemistry Key Laboratory of Theoretical&Computational Photochemistry of Ministry of EducationBeijing Normal UniversityBeijing 100190China

The formation of oligomeric hydrogen peroxide triggered by Criegee intermediate maybe contributes significantly to the formation and growth of secondary organic aerosol(SOA).However,to date,the reactivity of C2 Criegee intermediates(CH_(3)CHOO)in areas contaminated with acidic gas remains poorly ***,high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics(BOMD)simulations are used to explore the reaction of CH_(3)CHOO and H_(2)SO_(4)both in the gas phase and at the airwater *** the gas phase,the addition reaction of CH_(3)CHOO with H_(2)SO_(4)to generate CH_(3)HC(OOH)OSO_(3)H(HPES)is near-barrierless,regardless of the presence of water *** simulations showthat the reaction at the air-water interface is even faster than that in the gas *** calculations reveal that the HPES has a tendency to aggregate with sulfuric acids,ammonias,and water molecules to form stable clusters,meanwhile the oligomerization reaction of CH_(3)CHOO with HPES in the gas phase is both thermochemically and kinetically ***,it is noted that the interfacial HPES−ion can attract H_(2)SO_(4),NH_(3),(COOH)_(2)and HNO_(3)for particle formation from the gas phase to the water ***,the results of this work not only elucidate the high atmospheric reactivity of C2 Criegee intermediates in polluted regions,but also deepen our understanding of the formation process of atmospheric SOA induced by Criegee intermediates.

关键词： Criegee intermediates H_(2)SO_(4) Atmospheric behavior Air-water interface Chemical processes