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流态固化土水泥剂量EDTA滴定法检测影响因素分析

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大连理工大学学报 2025年第1期65卷 79-88页

作者：罗義錬罗强蒋良潍张良胡秋辉覃李兵西南交通大学土木工程学院四川成都610031 四川省名扬建设工程管理有限公司四川成都610017

水泥剂量是控制流态固化土强度的关键指标,工程中多采用EDTA滴定法进行检测,但流态固化土制备过程中含水量与水泥水化时间偏差会导致检测数据失真.研究了EDTA二钠标准溶液消耗量随水泥剂量、含水量和水化时间三因素的变化规律;基于回归... 详细信息

水泥剂量是控制流态固化土强度的关键指标,工程中多采用EDTA滴定法进行检测,但流态固化土制备过程中含水量与水泥水化时间偏差会导致检测数据失真.研究了EDTA二钠标准溶液消耗量随水泥剂量、含水量和水化时间三因素的变化规律;基于回归正交试验,开展了多因素及交互影响的主次关系分析与显著性评价,建立了考虑三因素综合影响的EDTA二钠标准溶液消耗量回归方程.试验表明,EDTA二钠标准溶液消耗量与水泥剂量近似呈线性正相关,随含水量增大或水化时间延长近似线性降低;影响因素主次顺序为水泥剂量、含水量、水化时间,交互作用不显著;因素水平在回归正交试验组范围内,回归方程计算值误差低于2.40%;含水量或水化时间分别偏差2.9%、86min,将造成水泥剂量检测值增减约0.5%.研究成果可为完善流态固化土水泥剂量检测技术提供参考.

关键词：流态固化土水泥剂量 EDTA滴定法回归正交试验因素主次关系

New Quantum MDS Code from Constacyclic Codes

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Chinese Annals of Mathematics,Series B 2016年第6期37卷 891-898页

作者： Liqin hu qin YUE Xiaomeng Zhu School of Communication Engineering Hangzhou Dianzi University Hangzhou 310018 China Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016China

In recent years, there have been intensive activities in the area of constructing quantum maximum distance separable(MDS for short) codes from constacyclic MDS codes through the Hermitian construction. In this paper, a new class of quantum MDS code is constructed, which extends the result of [Theorems 3.14–3.15, Kai, X., Zhu, S., and Li,P., IEEE Trans. on Inf. Theory, 60(4), 2014, 2080–2086], in the sense that our quantum MDS code has bigger minimum distance.

关键词： Cyclotomic coset Quantum MDS code Constacyclic code BCH bound

An improved morphological weighted dynamic similarity measurement algorithm for time series data

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International Journal of Intelligent Computing and Cybernetics 2018年第4期11卷 486-495页

作者： ke Yi Zhou Shaolin hu School of Automation and Information Engineering Xi’an University of TechnologyXi’anChina School of Automation Foshan UniversityFoshanChina

Purpose–The similarity measurement of time series is an important research in time series detection,which is a basic work of time series clustering,anomaly discovery,prediction and many other data mining *** purpose of this paper is to design a new similarity measurement algorithm to improve the performance of the original similarity measurement *** subsequence morphological information is taken into account by the proposed algorithm,and time series is represented by a pattern,so the similarity measurement algorithm is more ***/methodology/approach–Following some previous researches on similarity measurement,an improved method is *** new method combines morphological representation and dynamic time warping(DTW)technique to measure the similarities of time *** the segmentation of time series data into segments,three parameter values of median,point number and slope are introduced into the improved distance measurement *** effectiveness of the morphological weighted DTW algorithm(MW-DTW)is demonstrated by the example of momentum wheel data of an aircraft attitude control ***–The improved method is insensitive to the distortion and expansion of time axis and can be used to detect the morphological changes of time series *** results confirm that this method proposed in this paper has a high accuracy of similarity *** implications–This improved method has been used to solve the problem of similarity measurement in time series,which is widely emerged in different fields of science and engineering,such as the field of control,measurement,monitoring,process signal processing and economic ***/value–In the similarity measurement of time series,the distance between sequences is often used as the only detection *** results of similarity measurement should not be affected by the longitudinal or transverse stretching and translation changes of the sequence,s

关键词： Dynamic time warping Morphological representation Similarity measurement Time series data

Covalent organic frameworks functionalized carbon fiber paper for the capture and detection of hydroxyl radical in the atmosphere

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Chinese Chemical Letters 2020年第9期31卷 2495-2498页

作者： Zhiling huang qin Xu Xiaoya hu School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225002China Guangling College Yangzhou UniversityYangzhou 225002China

Developing a fast,sensitive and convenient method for the detection of hydroxyl radicals(·OH) in the atmosphere could help us know the precursor levels of atmospheric species and control air *** this work,the carbon fiber paper(CFP) functionalizing with a kind of covalent organic frameworks(COFs),formed from 1,3,5-triformylphloroglucinol(Tp) and benzidine(BD)(COF(TpBD)),was firstly used a new platform for ·OH trapping and *** COF(TpBD) modified CFP was acted as a filter to impregnate salicylic acid(SA) and a detector to detect 2,5-dihydroxybenzoic acid(2,5-DHBA) which was produced from the reaction between the impregnated SA and ’OH in the *** method provided a linearity for 2,5-DHBA from 5.0×10^-14 mol/L 1.0×10^-9 mol/L with a detection limit of 6.9×10^-15 mol/L,which is corresponding to the amount of ·OH from 3.0×10^7 to 6.0×10^11 molecules/cm3 with the detection limit of 4.1×10^6 molecules/*** COF(TpBD)-CFP platform has been successfully applied for the detection of ·OH concentration under different conditions of Yangzhou when the sampling time was shortened to 30 *** work has provided a new method for atmospheric·OH detection with excellent sensitivity,simplicity,and high speed.

关键词： Covalent organic frameworks Hydroxyl radical Electrochemical Detection

Numerical analysis and experimental investigation of wind turbine blades with innovative features:Structural response and characteristics

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Science China(Technological Sciences) 2015年第1期58卷 1-8页

作者： CHEN Xiao qin ZhiWen YANG ke ZHAO XiaoLu XU JianZhong National Laboratory of Wind Turbine Blade Research & Development Center Institute of Engineering ThermophysicsChinese Academy of Sciences

Innovative features of wind turbine blades with flatback at inboard region,thick airfoils at inboard as well as mid-span region and transversely stepped thickness in spar caps have been proposed by Institute of Engineering Thermophysics,Chinese Academy of Sciences(IET-Wind)in order to improve both aerodynamic and structural efficiency of rotor *** verify the proposed design concepts,this study first presented numerical analysis using finite element method to clarify the effect of flatback on local buckling strength of the inboard *** models with various loading cases,inboard configurations,and core materials were comparatively ***,a prototype blade incorporated with innovative features was manufactured and tested under static bending loads to investigate its structural response and *** was found that rotor blades with flatback exhibited favorable local buckling strength at the inboard region compared with those with conventional sharp trailing edge when low-density PVC foam was *** prototype blade showed linear behavior under extreme loads in spar caps,aft panels,shear web and flatback near the maximum chord which is usually susceptible to buckling in the blades according to traditional *** inboard region of the blade showed exceptional load-carrying capacity as it survived420%extreme loads in the *** this study,potential structural advantages by applying proposed structural features to large composite blades of multi-megawatt wind turbines were addressed.

关键词： wind energy rotor blade flatback local buckling extreme loads

Fracture mechanism of inclusions in thick plate center under tensile loading

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Journal of Iron and Steel Research International 2024年第5期31卷 1196-1209页

作者： Lei hu Li-qin Zhang Feng hu Guo-hong Zhang Kuan Zheng Collaborative Innovation Center for Advanced Steels Wuhan University of Science and TechnologyWuhan430081HubeiChina Department of Applied Physics Wuhan University of Science and TechnologyWuhan430081HubeiChina Analysis and Testing Center Wuhan University of Science and TechnologyWuhan430081HubeiChina

Segregation of solute atoms in the center of thick plates of the tempered steel can cause an inhomogeneous structural transformation and generate micron-sized inclusions,which leads to lamellar tearing of thick plate and decreases the plasticity and *** formation and fragmentation mechanisms of micron-sized inclusions,like MnS and(Nb,Ti)C,in the center of thick plates were investigated by using thermodynamic calculations,finite element simulations,and electron backscatter diffraction characterization *** results show that micron-sized inclusions nucleate and grow in the liquid phase,and under tensile loading,they exhibit three fragmentation *** local stress during the fragmentation of inclusions is lower than the critical fracture stress of adjacent grains,and phase boundaries can effectively impede crack propagation into the *** existence of a low proportion of high-angle grain boundaries(58.1%)and high kernel average misorientation value(0.534°)in the segregation band promotes inclusions fragmentation and crack *** difference in crack initiation and propagation direction caused by the morphology of inclusions and physical properties,as well as different matrix arrest abilities,is the main reasons for the diversity of inclusion fragmentation.

关键词： Thick plate Inclusion Finite element simulation Critical fracture stress Fracture mechanism

Phylogenetic analysis of Pectinidae (Bivalvia) based on the ribosomal DNA internal transcribed spacer region

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Acta Oceanologica Sinica 2007年第6期26卷 83-90页

作者： huANG Xiaoting BI ke hu Jingjie hu Xiaoli BAO Zhenmin Laboratory of Molecular Genetics and Breeding of Mollusk College of Marine Life Science Ocean University of China Qingdao 266003 China

The ribosomal DNA internal transcribed spacer （ITS） region is a useful genomic region for understanding evolutionary and genetic relationships. In the current study, the molecular phylogenetic analysis of Pectinidae （ Mollusca： Bivalvia） was performed using the nucleotide sequences of the nuclear ITS region in nine species of this family. The sequences were obtained from the scallop species Argopecten irradians, Mizuhopecten yessoensis, Amusium pleuronectes and Mimachlamys nobilis, and compared with the published sequences of Aequipecten opercularis, Chlamys farreri, C. distorta, M. varia, Pecten maximus, and an outgroup species Perna viridis. The molecular phylogenetic tree was constructed by the neighbor-joining and maximum parsimony methods. Phylogenetic analysis based on ITS1, ITS2, or their combination always yielded trees of similar topology. The results support the morphological classifications of bivalve and are nearly consistent with classification of two subfamilies （Chlamydinae and Pectininae） formulated by Waller. However, A. irradians, together with A. opercularis made up of genera Amusium, evidences that they may belong to the subfamily Pectinidae. The data are incompatible with the conclusion of Waller who placed them in Chlamydinae by morphological characteristics. These results provide new insights into the evolutionary relationships among scallop species and contribute to the improvement of existing classification systems.

关键词： bivalve Pectinidae ribosomal DNA ITS phylogeny

Engineering in amino acid-functionalized double-layer heteropolymolybdates:from structural control to catalytic activity

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Rare Metals 2023年第10期42卷 3345-3353页

作者： Lu-Lu Liu Yan-hu Wang Xin-Yu Xiao ke-Wei Tong Yue Zhao Chao-qin Chen Jing Du Peng Yang College of Chemistry and Chemical Engineering Advanced Catalytic Engineering Research Center of the Ministry of EducationHunan UniversityChangsha410082China Testing and Analysis Center Hebei Normal UniversityShijiazhuang050024China

A reexamination of the structural constraints on the amino acid-functionalized heteropolymolybdates has afforded four polyanions,namely the double-layer [(SeO_(3))_(2)Mo_(12)O_(36)(CH_(3)COO)_(3)]^(7-)(1),[(SeO_(3))_(1.3)(HPO_(3))_(0.7)Mo_(12)O_(36)(NH_(3)CH_(2)COO)_(3)]^(4-)(2),[(SeO_(3))_(1.4)(HPO_(3))_(0.6)Mo_(12)O_(36)(LNH_(3)C_(2)H_(3)OHCOO)_(3)]^(4-)(3),and the mono-layer [(SeO_(3))-Mo_6O_(18)(L-NH_(3)C_(2)H_(3)OHCOO)_(3)]^(2-)(4),which were crystallized as the hydrated ammonium salts.

关键词： structural layer double

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World Journal of Emergency Medicine 2022年第6期13卷 425-432页

作者： Hai hu Ni Yao Xiao-qin Lai Emergency Management Office of West China Hospital Sichuan UniversityChengdu 610041China China International Emergency Medical Team Chengdu 610041China Sichuan University’s Emergency Medical Rescue Base Chengdu 610041China Department of Critical Care Medicine West China HospitalSichuan UniversityChengdu 610041China Day Surgery Center West China HospitalSichuan UniversityChengdu 610041China West China School of Nursing Sichuan UniversityChengdu 610041China

BACKGROUND:There is limited evidence for emergency physicians and emergency trauma surgeons regarding the determinants of early and rapid assessment of older adult in-hospital mortality due to *** study explored factors related to the early and rapid assessment of the mortality among older adult earthquake trauma patients(OAETPs)and created a screening ***:Data on 7,308 OAETPs from the West China Earthquake Patients Database were analyzed *** 35 variables that can be obtained rapidly on arrival at the hospital were *** absolute shrinkage and selection operator(LASSO)regression analysis was ***,the nomogram for assessing the mortality of OAETPs was ***:We identified 10 independent mortality-related factors that contributed to the in-hospital mortality of *** 10 factors included age(odds ratio[OR]=1.061,95%confidence interval[CI]:1.031-1.090),dementia(OR=5.146,95%CI:1.169-17.856),coronary heart disease(CHD;OR=23.441,95%CI:4.799-83.927),malignant tumor(OR=8.497,95%CI:3.583-17.967),deep vein thrombosis(DVT;OR=7.110,95%CI:1.369-27.168),chronic kidney disease(CKD;OR=11.783,95%CI:5.419-24.407),pulse rate(PR;OR=1.036,95%CI:1.022-1.048),mean artery pressure(MAP;OR=0.960,95%CI:0.945-0.975),Glasgow Coma Scale(GCS;OR=0.864,95%CI:0.760-0.972),and Triage Revised Trauma Score(T-RTS,OR=0.485,95%CI:0.351-0.696).CONCLUSION:The 10 mortality-related factors could be quickly obtained on hospital arrival and should be the focal point of future earthquake response strategies regarding hospitalized older adults with trauma.A nomogram was constructed based on the factors for screening OAETPs with a higher risk of in-hospital mortality.

关键词： Trauma Mortality Earthquakes Elderly patients