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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 605-620页

作者： Xie qiang Wu Zhi-Hui dong Jie Zhong Shuai School of Civil Engineering Chongqing UniversityChongqing 400045China College of Civil Engineering Hebei University of ArchitectureZhangjiakou 075000China

This paper presents a comparative analysis of ground vibration in three directions generated by a heavy-duty railway with various track *** vibration characteristics in the plane area were investigated by using matrix test *** peak attenuation was faster within 25 m from the embankment,and the high-frequency vibration attenuates faster with increased *** the cutting section with multi-stage soil slope,decay rate of acceleration was relatively *** acceleration level of the plane region ranged to 82.2-89.1 dB by the single C80 *** the acceleration level caused by the C80 trains running parallel after meeting showed a distinct *** increment of the cutting section was much larger compared with the embankment section,with the increment ranging from 1.2-2.5 *** terms of the cutting section,y direction acceleration was dominant closer to the *** 10-30 m of the track,the y direction acceleration(perpendicular to the rail)decreased rapidly and became comparable to the X direction(parallel to the rail)and Z ***,the cutting case generated a higher level of vibration in all three directions compared to the embankment,but as the distance from track increased,the deviation between acceleration gradually decreased.

关键词： heavy-duty railway different track sections field measurement vibration response characteristics cutting slope

Analysis of a landfill cover without geomembrane using varied particle sizes of recycled concrete

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第5期15卷 1263-1273页

作者： Charles Wang Wai ng Cheuk Lam ng Junjun Ni Haowen Guo Qi Zhang qiang Xue Rui Chen Department of Civil and Environmental Engineering Hong Kong University of Science and TechnologyHong KongChina School of Transportation Southeast UniversityNanjingChina State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China Department of Civil and Environmental Engineering Shenzhen Graduate SchoolHarbin Institute of TechnologyShenzhenChina

Previous studies have demonstrated the effectiveness of a novel three-layer landfill cover system constructed with recycled concrete aggregates(RCAs)without geomembrane in both laboratory and ***,no systematic investigation has been carried out to optimize the combination of the particle sizes for fine-grained RCAs(FRC)and coarse-grained RCAs(CRC)that can be used for the three-layer landfill cover *** aim of this paper is to assist engineers in designing the three-layer landfill cover system under a rainfall of 100-year return period in humid climate conditions using an easily controlled soil parameter D10 of *** numerical study reveals that when D10 of FRC increases from 0.05 mm to 0.16 mm,its saturated permeability increases by 10 *** a result,a larger amount of rainwater infiltrates into the cover system,causing a higher lateral diversion in both the top FRC and middle CRC *** further changes in the lateral diversion are observed when the D10 value of FRC is larger than 0.16 *** the particle sizes of FRC and CRC layers are shown to have a minor influence on the percolation under the extreme rainfall *** implies that the selection of particle sizes for the FRC and CRC layers can be based on the availability of *** it is well known that the bottom layer of the cover system should be constructed with very fine-grained soils if possible,this study provides an upper limit to the particle size that can be used in the bottom layer(D10 not larger than 0.02 mm).With this limit,the three-layer system can still minimize the water percolation to meet the design criterion(30 mm/yr)even under a 100-year return period of rainfall in humid climates.

关键词： Capillary barrier Landfill cover Particle size Recycled concrete

Methods and mechanisms for uniformly refining deformed mixed and coarse grains inside a solution-treated Ni-based superalloy by two-stage heat treatment

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Journal of Materials Science & Technology 2021年第18期77卷 47-57页

作者： Guan-qiang Wang Ming-Song Chen Hong-Bin Li y.C.Lin Wei-dong Zeng yan-y.ng Ma School of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China Light Alloy Research Institute Central South UniversityChangsha 410083China State Key Laboratory of High Performance Complex Manufacturing Changsha 410083China College of Metallurgies and Energy North China University Science and TechnologyTangshan 063009China

The uniform refinement mechanisms and methods of deformed mixed and coarse grains inside a solution-treatment Ni-based superalloy during two-stage annealing treatment have been *** two-stage heat treatment experiments include an aging annealing treatment(AT)and a subsequent recrystallization annealing treatment(RT).The object of AT is to precipitate someδphases and consume part of storage energy to inhibit the grain growth during RT,while the RT is to refine mixed and coarse grains by *** can be found that the recrystallization grains will quickly grow up to a large size when the AT time is too low or the RT temperature is too high,while the deformed coarse grains cannot be eliminated when the AT time is too long or the RT temperature is too *** addition,the mixed microstructure composed of some abnormal coarse recrystallization grains(ACRGs)and a large number of fine grains can be observed in the annealed specimen when the AT time is 3 h and RT temperature is 980℃.The phenomenon attributes to the uneven distribution ofδphase resulted from the heterogeneous deformation energy when the AT time is too *** the regions with a large number ofδphases,the recrystallization nucleation rate is promoted and the growth of grains is limited,which results in fine ***,in the regions with fewδphases,the recrystallization grains around grain boundaries can easily grow up,and the new recrystallization nucleus is difficult to form inside grain,which leads to ***,in order to obtain uniform and fine annealed microstructure,it is a prerequisite to precipitate even-distributedδphase by choosing a suitable AT time,such as 12 ***,a relative high RT temperature is also needed to promote the recrystallization nucleation aroundδ*** optimal annealing parameters range for uniformly refining mixed crystal can be summarized as:900℃×12 h+990℃×(40-60 min)and 900℃×12 h+1000℃×(10-15 min).

关键词： Ni-based superalloy Aging annealing Recrystallization annealing Grain refinement Microstructural evolution Mixed grain microstructure

Efficacy and adverse effects of oral propranolol in infantile hemangioma:a meta-analysis of comparative studies

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World Journal of Pediatrics 2019年第6期15卷 546-558页

作者： Hao y.ng dong-Lai Hu qiang Shu Xiao-dong Guo Department of Pediatrics Surgery Jinhua Central HospitalNo.365 Renmindong RoadWucheng DistrictJinhua 321000China Children's Hospital Zhejiang University School of MedicineNo.3333 Binsheng RoadBinjiang DistrictHangzhou 310052China

Background A number of clinical trials evaluated the efficacy and adverse effects of oral propranolol in the treatment of infantile hemangioma(IH),but the treatment has not yet been *** meta-analysis aims to reevaluate the efficacy and adverse effects of oral propranolol in comparative studies and to provide a reliable basis for clinical administration in the therapy for *** Data were obtained from PubMed,Embase,Cochrane Library,Web of Science,China National Knowledge Infra-structure and Wanfang database,from inception to December 1st,*** pooled risk ratios(RR)with 95%confidence intervals(95%CI)were calculated and used to evaluate the effect *** meta-analysis was performed using the random-effects model due to heterogeneity between the *** Cochrane Collaboration 6 aspects of bias,methodological index for non-randomized studies and the Newcastle-Ottawa Scale were used to assess the risk for *** analysis,publication bias and subgroup analysis were *** Eighteen unique studies involving 2701 unique children were included in the *** response rate was reported in 18 trials,which compared oral propranolol with other *** heterogeneity was statistically significant(Py significant(RR=1.40,95%CI 1.13-1.75)while compared with the ***,no significant difference in the adverse events rate(RR=0.78,95%CI 0.45-1.34)and relapse rate(RR=1.45,95%CI 0.66-3.16)were ***,the subgroup analysis indicated that the RR was 1.64(95%CI 0.24-11.36)for low-dose propranolol(1 mg/kg/day),1.42(95%CI 1.12-1.80)for medium dose(2 mg/kg/day)and 1.46(95%CI 1.17-1.82)for high dose(3 mg/kg/day),but the high dose had higher adverse events rate than medium dose,with 3.60%and 86.22%,*** effectiveness of propranolol therapy among cases of treatment duration less than 6 months(RR=1.24,95%CI 1.05-1.47)was inferior to that of t

关键词： Hemangioma Meta-analysis Propranolol

Devitrification of Al-Ce Amorphous Ribbon Investigated Using In situ High Energy X-ray Diffraction

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Acta Metallurgica Sinica(English Letters) 2022年第1期35卷 157-162页

作者： y.ng-Xi Li Fan-qiang Meng Rui yuan Guo-qiang Huang dong-Bai Sun Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai519082China School of Materials Science and Engineering Sun Yat-Sen UniversityGuangzhou510275China

Metastable phases formed during vitrification or devitrification open an avenue to study the intrinsic structural hierarchy in amorphous *** phase transformation sequence of Al89Ce11 amorphous ribbon was investigated using diff erential scanning calorimetry,in situ high energy X-ray diffraction(HEXRD)and ex situ high-resolution scanning transmission electron *** results reveal the devitrification pathway following the reaction:amorphous→ε-Al_(60)Ce_(11)+fcc-Al→η-Al_(41)Ce_(5)+fcc-Al→Al_(11)Ce_(3)+*** has been found that bothε-Al_(60)Ce_(11)andη-Al_(41)Ce_(5)metastable phases have same Ce-centered 1-6-6-6-1 motif,suggesting that the structural motif can be *** of metastable phase with large unit cell is related to the short-range orders developed during *** heredity provides a new method to tailor the microstructure and properties of Al-based alloys based on genetic mechanism.

关键词： Synchrotron radiation Amorphous alloys Crystallization Phase transformation

Impurity formation mechanism of silicon carbide crystals smelted by Acheson process

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Journal of Iron and Steel Research International 2024年第6期31卷 1367-1375页

作者： dong Feng Hong-qiang Ru Xu-dong Luo Jie-gang you Ling Zhang School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Institute of Advanced CeramicsSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819LiaoningChina Liaoning Institute of Science and Technology Benxi 117004LiaoningChina

In order to further promote the application of SiC refractories in modern steel metallurgy,the occurrence forms and formation mechanism of impurities in SiC crystals smelted by Acheson process were *** techniques of inductively coupled plasma-atomic emission spectrometry,X-ray diffraction,and scanning electron microscopy were combined to examine the types and occurrence forms of impurities in smelted SiC *** results showed that the main impurities in the SiC are free Si,free C,oxides(CaO·Al_(2)O_(3)·2SiO_(2),3Al_(2)O_(3)·2SiO_(2),CaO·SiO_(2) and SiO_(2))and alloy phases(Fe_(x)Si_(y),Fe_(x)Si_(y)Ti_(z) and Fe_(x)Al_(y)Si_(z)).The formation process of impurities during the smelting of SiC can be described as follows:At high temperature,the SiO_(2) and Fe,Ti related oxide impurities present in the raw materials are reduced to Si,Fe,and Ti metal *** the reduction process,the free Si,Fe_(x)Si_(y) and Fe_(x)Si_(y)Ti_(z) are precipitated from the melt during *** Si primarily exists in aggregated form within the SiC crystal,while the alloy phase is predominantly found at the interface between SiC and free Si,with Fe_(x)Si_(y)Ti_(z) embedded within *** the end of the cooling process,other impurity oxides such as Al_(2)O_(3),CaO,and some unreduced SiO_(2) solidify to form calcium-aluminum-silicate glass phases,predominantly located between SiC *** remaining C from the reaction is mainly dispersed as free C within the SiC crystal and at the interface between SiC and free Si.

关键词： Impurity element Formation mechanism Smelted SiC crystal SiC refractory Occurrence form

SURFACE AND INTERFACIAL GRAVITy WAVES INDUCED By AN IMPULSIVE DISTURBANCE IN A TWO-LAyER INVISCID FLUID

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Journal of Hydrodynamics 2009年第1期21卷 26-33页

作者： LU dong-qiang CHEN Ting-ting Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

The transient gravity waves due to an impulsive source in a two-layer fluid system are investigated analytically. The fluid is assumed to be inviscid and incompressible. The density of each of the two layers is constant. Five different boundary conditions are considered. The depth of each of the two layers is infinite or finite. The upper fluid of finite depth is covered by a rigid lid or a free surface. Based on the assumption of small-amplitude waves, a linear system is established. The integral solutions for the free-surface and interfacial waves are obtained by means of the Fourier-Laplace transform. The corresponding asymptotic representations are derived for large time with a fixed distance-to-time ratio by the Stokes and Scorer methods of stationary phase. The analytical solutions show that there are two different modes, namely the free-surface and interracial wave modes. The wave profiles observed depend on the relation between the distance-to-time ratio and the maximal group velocities and on the limiting values of the second derivatives of the frequencies as well.

关键词： impulsive disturbances imerfacial waves free surface waves stationary-phase methods

Therapy and prognostic features of primary clear cell carcinoma of the liver

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World Journal of Gastroenterology 2010年第6期16卷 764-769页

作者： Ji, Sheng-Pu Li, qiang dong, Hui Tianjin Med Univ Canc Hosp Dept Hepatobiliary Surg Tianjin 300060 Peoples R China

AIM:To clarify the therapeutic strategies and prognosis factors of primary clear cell carcinoma of the liver(PCCCL) . METHODS:The clinical pathological data of 64 patients with PCCCL treated with hepatectomy in our hospital from January 2000 to January 2006 were analyzed *** patients were divided into two groups to make treatment analysis:curative resection only(n=40) ;and curative resection and postoperative chemotherapy with calcium folinate and tegafur(n= 24) .Meanwhile,the PCCCL patients were subdivided into two subgroups on the basis of the proportion of clear cells in the tumor for pathological *** were 36 cases in subgroup A for which the proportion of clear cells was more than 70%,and 28 cases in subgroup B for which the proportion was less or equal to 70%,comparing analysis of median survival time of the counterpart *** and multivariate analyses were performed to examine factors that affect-ed clinical prognosis,recurrence and metastasis. RESULTS:Median survival period of the curative surgery group was 38 mo,while the counterpart was 41 *** survival period for group A was 41 mo,while group B was 19 *** Kaplan-Meier method showed that capsule formation,preoperative liver function,hepatitis C virus infection,large vascular invasion and multiple tumor occurrences were related to disease-free *** regression analysis showed that the clear cell ratio,capsule formation,preoperative liver function and large vascular invasion were independent risk factors for overall survival. CONCLUSION:Postoperative chemotherapy has no obvious effect on survival of patients with PCCCL. Clear cell ratio,capsule formation,preoperative liver function,and vascular invasion were independent risk factors for prognosis.

关键词： Clear cell carcinoma Hepatectomy Prognosis Treatment Risk factor

Comparison of two bedside evaluation methods of dysphagia in patients with acute stroke

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Stroke & Vascular Neurology 2018年第4期3卷 237-244页

作者： Ting ye Shengyan Huang yi dong qiang dong Neurology Unit Huashan HospitalFudan UniversityShanghaiChina State Key Laboratory of Medical Neurobiology Fudan UniversityShanghaiShanghaiChina

Background Dysphagia is a common complication after *** swallowing test(WST)is a recognised but limited tool in providing details about dysphagia,including severity and how to adjust the diet based on the test *** We performed a prospective observational study of comparing WST and volume-viscosity swallow test(V-VST)in patients with acute stroke within 14 *** patients had WST and if failed would have a *** primary outcome was to compare the dysphagia levels assessed by these two test *** secondary outcome was to explore the predictive capability in patients who were at high risk of pneumonia by these two swallowing *** Consecutively 276 patients with stroke were enrolled in our study,and 197 had normal *** 79 patients who had both WST and V-VST,20 showed swallowing safety and effectiveness by *** chance of being on tube feeding was strongly related to the positive results of failed WST(py in patients with stroke for pneumonia even some of them were placed on tube feeding(p=0.001 in WST and png test for dysphagia in patients with acute stroke at the *** registration number ChiCTR1800016442.

关键词： patients details viscosity

A Note on the Single Genotype Resolution Problem

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Journal of Computer Science & Technology 2004年第2期19卷 254-256,F003页

作者： HaoLin Ze-FengZhang qiang-FengZhang dong-BoBu MingLi BioinformaticsLab InstituteofComputingTechnologyTheChineseAcademyofSciencesBeijing100080P.R.China UniversityofScienceandTechnologyofChina Hefei230026.P.R.China UniversityofWaterloo Canada

This note settles the complexity of the single genotype resolution problemshowing it is NP-complete. This solves an open problem raised by P. Bonizzoni, G.D. Vedova, ***, and J. Li. The same proof also gives an altern... 详细信息

关键词： haplotype inference single genotype resolution maximum resolution NP-completeness