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Abnormality diagnosis of cracks in the concrete based on double crack tip opening displacement criterion

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Science China(Technological Sciences) 2013年第8期56卷 1915-1928页

作者： li zhanchao GU ChongShi WU ZhongRu College of Water Resources and Architectural Engineering Northwest A&F University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Water Conservancy and Hydropower Engineering Hohai University

The distinct characteristic of subcritical propagation requires at least two control parameters to completely express expansion of cracks in the *** basic definition of crack tip opening displacement(CTOD)is corrected based on the monitored variable of crack mouth opening displacement(CMOD).The improved CTOD criterion,called the double CTODd criterion,for the abnormality diagnosis of cracks in the concrete is constructed based on the fictitious crack model and linear asymptotic superposition assumptions of the *** double CTODd criterion is verified using two specimens of three-point bending notched *** verification results are reasonable and *** establishment of the double CTODd criterion lays a solid theoretical foundation for the abnormality diagnosis of cracks in concrete structures(such as concrete dams)based on CMOD.

关键词： concrete cracks abnormality diagnosis double CTODd criterion

High tension cyclic hydrocarbons synthesized from biomass-derived platform molecules for aviation fuels in two steps

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Green Energy & Environment 2023年第1期8卷 331-337页

作者： zhanchao li Yizhuo Wang Qing li liqing Xu Hong Wang Frontier Institute of Science and Technology Xi'an Jiaotong UniversityXi'an710054China State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an710054China

Synthesizing ring structure aviation fuels from biomass-derived platform molecules is challenging,especially for bridged ring structure aviation fuels which are typically achieved from fossil-derived ***,we report the synthesis of a series of ring structure biofuels in two steps by a combination of a solvent-free Michael-cyclization reaction and a hydrodeoxygenation(HDO)reaction from lignocellulosederived 5,5-dimethyl-1,*** biofuels are obtained with high overall yields up to 90%,which exhibit high densities of 0.81 g cm^(-3)-0.88 g cm^(-3)and high volumetric neat heat of combustion(VNHOC)values of 36.0 MJ L^(-1)-38.6 MJ L^(-1).More importantly,bridged-ring structure hydrocarbons can also be achieved in two steps by a combination of a Robinson annulation reaction and an HDO reaction to afford the final products at high overall yields up to 90%.The bridged-ring structure products have comparable high densities and high VNHOC values to the best artificial fuel JP-10(0.94 g cm^(-3)and 39.6 MJ L^(-1)).The results demonstrate a promising way for the synthesis of high-density aviation fuels with different fuel properties at high yields.

关键词： Biofuels 5,5-Dimethyl-1,3-cyclohexanedione Solvent-free Michael-cyclization Robinson annulation Green reaction

On-line diagnosis method of crack behavior abnormality in concrete dams based on fluctuation of sequential parameter estimates

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Science China(Technological Sciences) 2015年第3期58卷 415-424页

作者： li zhanchao GU ChongShi WANG ZhengZhong WU ZhongRu College of Water Resources and Architectural Engineering Northwest A&F University State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Water Conservancy and Hydropower Engineering Hohai University

Research on on-line diagnosis method of crack behavior abnormality in concrete dams can provide support for timely grasping abnormality state of the crack itself and achieving real-time monitoring of the dam *** that samples of crack effects in concrete dams increase actually over monitoring time,a superiority criterion for the on-line diagnosis is determined so as to detect the abnormality moments timely and *** integrating the safety monitoring statistical model of crack effect variable with change point theory,a fluctuation method of regression coefficients is established for the on-line *** addition,each abnormality moment is detected by the cumulative sum of regression model *** indicate that abnormality of crack behavior in concrete dams can be characterized by structural instability of crack monitoring *** causes of crack behavior abnormality can be analyzed by the established method,which will play an important role in dam safety ***,taking the crack in a concrete gravity-arch dam as an example,the scientific rationality and validity of the established on-line diagnosis method are confirmed.

关键词： concrete dams crack behavior abnormality on-line diagnosis fluctuation of regression coefficients

Commentary of research situation and innovation frontier in hydro-structure engineering science

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Science China(Technological Sciences) 2011年第4期54卷 767-780页

作者： WU ZhongRu PENG Yan li zhanchao li Bo YU Hong ZHENG ShouRen State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai UniversityNanjing 210098China Changjiang Water Resource Commission Wuhan 430071China

In order to utilize water and hydropower resources in China,multitudes of water projects are established or to be constructed as an integral part of the national economy's *** these circumstances,there are two outstanding problems:1) a mass of existing dams are in danger and 2) in the southwest water-conservancy construction plan,dozens of existing or planned dams are high dams or even super high dams with heights between 200 and 300 *** accordance with demands of "the National Program for Medium-and Long-Term Scientific and Technological Development" on the innovation frontier in hydro-structure engineering science,various key problems in science and technology such like stress analysis,ultimate bearing capacity,nonlinearity *** high dams,super high dams and sick dams have been *** paper makes a commentary on the advances and results of the researches,then analyzes the advantages and disadvantages of current theoretics and methodologies,and finally presents corresponding research directions and the frontier of innovation.

关键词： hydro-structure engineering science research situation innovation frontier stress analysis ultimate bearing capacity nonlinearity commentary

Supplemental Feeding of Laying Hens with Wood Vinegar to Decrease the Ratio of n-6 to n-3 Fatty Acids in Eggs

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Chemical Research in Chinese Universities 2019年第6期35卷 983-989页

作者： ZHAO Nan XIN Hua li zhanchao WANG Ziming ZHANG Lening Department of Thoracic Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130031P.R.China College of Chemistry Jilin UniversityChangchun 130012P.R.China

A balanced ratio of fatty acids n-6 to n-3 in chicken eggs is important for health and to help prevent and manage obesity and other ***,fish oil or flax seed has been utilized as feed additives to decrease the ratio of n-6 to n-3(n-6:n-3)fatty acids in *** hull of spina date seed(HSDS)is a common agricultural waste product in China,from which wood vinegar(HSDSWV)may be *** study evaluated HSDSWV as a sup-plement in hen feeds to improve the quality of eggs and decrease the ratio of fatty acids n-6:*** was obtained via carbonization,and *** concentrations(nil to 0.5%)of HSDSWV were prepared and fed to 6 hen groups,respectively,for 50 *** fatty acids of the hen’s egg yolks were analyzed by gas chromatography/electron ionization-mass spectrometry(GC/EI-MS)in the selected ion monitoring(SIM)*** 0.2%HSDSWV resulted in the best egg yolk quality,with a lower percentage of linoleic acid(C18:2n6)and higher percentages of cis-5,8,11,14,17-eicosapentaenoic acid(C20:5n3)and cis-4,7,10,13,16,19-docosahexaenoic acid(C22:6n3),and thus a lower n-6:n-3 ratio compared with the other HSDSWV *** addition,the eggs contained higher levels of yolk fat and egg yolk than the controls *** conclusion,to modify the fatty acid composition of hens’eggs and obtain a balanced ratio of n-6:n-3,0.2%HSDSWV may be considered suitable as a dietary supplement in hens’feed.

关键词： Gas chromatography/electron ionization-mass spectrometry(GC/EI-MS) Hull of spina date seed Wood vinegar n-3 fatty acid n-6 fatty acid

Characterization of Five Kinds of Wood Vinegar Obtained from Agricultural and Forestry Wastes and Identification of Major Antioxidants in Wood Vinegar

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Chemical Research in Chinese Universities 2019年第1期35卷 12-20页

作者： li zhanchao ZHANG Zhiquan WU lijie ZHANG Hanqi WANG Ziming College of Chemistry Jilin UniversityChangchun 130012P.R.China College of Chinese Materia Media Tianjin University of Traditional Chinese Medicine Tianjin 300193P.R.China

Wood vinegar(WV)has a powerful antioxidant activity,but it is unclear which components are responsible for the antioxidant *** the present study,the double-column retention index qualitative method was used for the identification of the major components in five kinds of W7 And the major antioxidants of wood vinegar were accurately identified with the aid of Pearson product-moment correlation coefficients and authentic standard samples. Our results demonstrate that phenolic compounds are mainly responsible for the powerful antioxidant activity. 2,6-Dimethoxyphenol is the most powerful antioxidant in WV.2-Methoxyphenol and 3-methyl-1,2-cyclopentanedioue also have an important influence on the antioxidant activity of *** results suggest that the contents of 2-methoxyphenol,2,6-dimethoxyphenol and 3-methyl-1,2-cyclopentanedione should act as the criteria for evaluating the antioxidant activity of *** work will provide useful information for WV's application in the fields of food and medicine as antioxidants.

关键词： Antioxidant activity 2,6-Dimethoxyphenol 3-Methyl-1,2-cyclopentanedione 2-Methoxyphenol Retention index Wood vinegar

Preparation and Characterization of Two Wood Vinegars Obtained from Hull of Spina Date Seed and Shell of Peanut

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Chemical Research in Chinese Universities 2017年第3期33卷 348-353页

作者： li zhanchao ZHANG Zhiquan WU lijie WANG Jichang liU Zhenheng ZHANG Zhongwei ZHANG Hanqi WANG Ziming College of Chemistry Jilin University Changchun 130012 P. R. China JidongKeda Biomass Energy Technology Co. Ltd. of Songyuan City Songyuan 138000 P. R. China Bureau of Animal Husbandry Songyuan 138000 P. R. China

Two new kinds of wood vinegars（WVs） from the hull of spina date seed（HSDS） and the shell of peanut（PS） were prepared. 32 Major components in the two kinds of WVs were identified and determined by gas chro- matograph-mass spectrometery. The total phenolic content was determined and the antioxidant activity of the WV was measured. The total phenolic contents of PSWV and HSDSWV were 75.9 and 98.1 rag/L, respectively, when they were expressed as catechol equivalents. In 1,1-diphenyl-2-picrylhydrazyl assay, free radical scavenging activity of HSDSWV was also superior than that of PSWV. In addition, the antioxidant activities of the two kind of WVs exhibited a good positive correlation with total phenolic content, and the linear correlation coefficients ranged from 0.9594 to 0.9970. The two kind of WVs could be used in the fields of food and medicine due to their powerful antioxidant activities.

关键词： Hull of spina date seed Shell of peanut Wood vinegar Total phenolic content Antioxidant activity Free radical scavenging activity

P-Type Chemical Doping-Induced High Bipolar Electrical Conductivities in a Thermoelectric Donor–Acceptor Copolymer

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CCS Chemistry 2021年第10期3卷 2482-2493页

作者： Jing Wang Yizhuo Wang Qing li zhanchao li Kuncai li Hong Wang Frontier Institute of Science and Technology Xi’an Jiaotong UniversityXi’an 710054 State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an 710054

Typically,conducting polymers transfer either electrons or *** is rare to see high bipolar(p-and n-type)electrical conductivities within a single bulk doped organic polymer without the assistant of gate ***,we report that FeCl3-doped solutionprocessable D–A copolymer poly(2,5-bis(2-octyldo decyl)-3,6-di(thiophen-2-yl)diketopyrrolo[3,4-c]pyrrole-1,4-dione-alt-thieno[3,2-b]thiophen)(DPPTTT)could exhibit a high p-type electrical conductivity of 130.6 S/cm and a good n-type electrical conductivity of 14.2 S/cm by engineering the doping level.

关键词： polarity switching donor-acceptor copoly mer thermoelectric organic diode p-ty pe doping

Comprehensive evaluation methods for dam service status

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Science China(Technological Sciences) 2012年第11期55卷 2300-2312页

作者： WU ZhongRu XU Bo GU ChongShi li zhanchao State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Hohai UniversityNanjing 210098China

More than 87000 dams have been built in China,and about one third of them are risky projects.A number of high and ultra-high dams are being constructed in China's western *** current dam construction practice tends to focus on socio-economic benefits and neglect the environment and ***,periodic examinations are intended to ensure the structural safety of *** paper proposes a general evaluation principle for dam *** principle stipulates that dam projects should have maximum socio-economic benefits and minimum negative effects on the environment and *** satisfy the general principle of mutual harmony,socio-economic benefits,dam safety,environment,and ecology are analyzed,and the evaluation methods for dam service status are ***,a fusion algorithm of interlayer assessment is proposed on the basis of evidence theory and the fuzzy comprehensive analysis ***,a comprehensive evaluation model is *** analysis shows that the proposed theories and methods can fulfill scientific assessment of the service status of dams.

关键词： dam service status assessment principles evaluation methods comprehensive evaluation model

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