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Influence of Incomplete Soil Plugs on Bearing Capacities of Bucket Foundations in Clay
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作者 LI Hui-shan LIU Run +1 位作者 YANG Xu LIAN Ji-jian 《China Ocean Engineering》 SCIE EI CSCD 2024年第1期144-155,共12页
Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be eval... Due to the uneven seabed and heaving of soil during pumping,incomplete soil plugs may occur during the installation of bucket foundations,and the impacts on the bearing capacities of bucket foundations need to be evaluated.In this paper,the contact ratio(the ratio of the top diameter of the soil plug to the diameter of the bucket)and the soil plug ratio(the ratio of the soil heave height to the skirt height)are defined to describe the shape and size of the incomplete soil plug.Then,finite element models are established to investigate the bearing capacities of bucket foundations with incomplete soil plugs and the influences of the contact ratios,and the soil plug ratios on the bearing capacities are analyzed.The results show that the vertical bearing capacity of bucket foundations in homogeneous soil continuously improves with the increase of the contact ratio.However,in normally consolidated soil,the vertical bearing capacity barely changes when the contact ratio is smaller than 0.75,while the bearing capacity suddenly increases when the contact ratio increases to 1 due to the change of failure mode.The contact ratio hardly affects the horizontal bearing capacity of bucket foundations.Moreover,the moment bearing capacity improves with the increase of the contact ratio for small aspect ratios,but hardly varies with increasing contact ratio for aspect ratios larger than 0.5.Consequently,the reduction coefficient method is proposed based on this analysis to calculate the bearing capacities of bucket foundations considering the influence of incomplete soil plugs.The comparison results show that the proposed reduction coefficient method can be used to evaluate the influences of incomplete soil plug on the bearing capacities of bucket foundations. 展开更多
关键词 bucket foundation incomplete soil plug uniaxial bearing capacity contact ratio soil plug ratio
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Optimization on microstructure,mechanical properties and damping capacities of duplex structured Mg–8Li–4Zn–1Mn alloys 被引量:1
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作者 Tongtong Cao Yong Zhu +7 位作者 Yuyang Gao Yan Yang Gang Zhou Xiaofei Cui Chen Wen Bin Jiang Xiaodong Peng Fusheng Pan 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2023年第5期949-958,共10页
Optimizing the mechanical properties and damping capacity of the duplex-structured Mg–Li–Zn–Mn alloy by tailoring the microstructure via hot extrusion was investigated.The results show that the Mg–8Li–4Zn–1Mn al... Optimizing the mechanical properties and damping capacity of the duplex-structured Mg–Li–Zn–Mn alloy by tailoring the microstructure via hot extrusion was investigated.The results show that the Mg–8Li–4Zn–1Mn alloy is mainly composed ofα-Mg,β-Li,Mg–Li–Zn and Mn phases.The microstructure of the test alloy is refined owing to dynamic recrystallization(DRX)during hot extrusion.After hot extrusion,the crushed precipitates are uniformly distributed in the test alloy.The yield strength(YS),ultimate tensile strength(UTS),and elongation(EL)of as-extruded alloy reach 156 MPa,208 MPa,and 32.3%,respectively,which are much better than that of as-cast alloy.Furthermore,the as-extruded and as-cast alloys both exhibit superior damping capacities,with the damping capacity(Q^(-1))of 0.030 and 0.033 at the strain amplitude of 2×10^(-3),respectively.The mechanical properties of the test alloy can be significantly improved by hot extrusion,whereas the damping capacities have no noticeable change,which indicates that the duplex-structured Mg–Li alloys with appropriate mechanical properties and damping properties can be obtained by alloying and hot extrusion. 展开更多
关键词 magnesium–lithium alloys hot extrusion MICROSTRUCTURE mechanical properties damping capacity
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Perceived stress and coping capacities among frontline healthcare workers of AIIMS during COVID-19 pandemic:A cross-sectional study
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作者 Mudita Sharma Digpal Singh Chundawat +2 位作者 Rohit Richhariya Sunil Kumar Tailor Shatrughan Pareek 《Journal of Acute Disease》 2023年第2期67-72,共6页
Objective:To assess perceived stress and coping capacity of frontline health workers from AIIMS during COVID-19 pandemic.Methods:This cross-sectional study conducted from May to July 2021 enrolled 694 participants.An ... Objective:To assess perceived stress and coping capacity of frontline health workers from AIIMS during COVID-19 pandemic.Methods:This cross-sectional study conducted from May to July 2021 enrolled 694 participants.An online questionnaire based on Google Forms was developed to collect the data.Participants were assessed using the validated Perceived Stress Scale and the Coping Resources Inventory Scale.Results:The age of participants were 27(23-52)years old.The majority of respondents(73.5%)felt moderately stressed.Of the 694 participants,83.0%of the 576 participants had average stress management skills.Sex,marital status,and profession were significantly associated with perceived stress.In addition,marital status and profession were significantly associated with coping capacity.Conclusions:The majority of participants have moderate stress levels and average coping skills.Frontline healthcare workers have to maintain mental and physical health.Achieving this requires early screening and stress management for healthcare workers. 展开更多
关键词 COVID-19 PREVALENCE Perceived stress Coping capacity Frontline health workers Mental health
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The transformation of LPSO type in Mg-4Y-2Er-2Zn-0.6Zr and its response to the mechanical properties and damping capacities 被引量:13
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作者 Dan Wang Huajie Wu +6 位作者 Ruizhi Wu Yang Wang Jinghuai Zhang Sergey Betsofen Boris Krit Legan Hou Turahodjayev Nodir 《Journal of Magnesium and Alloys》 SCIE EI CAS 2020年第3期793-798,共6页
The transformation of LPSO type in Mg-4Y-2Er-2Zn-0.6Zr during heat treatment and its influence on damping and mechanical properties are reported in this work.Prior to heat treatment,the alloy consisted of a-Mg matrix ... The transformation of LPSO type in Mg-4Y-2Er-2Zn-0.6Zr during heat treatment and its influence on damping and mechanical properties are reported in this work.Prior to heat treatment,the alloy consisted of a-Mg matrix and lamellar 14H LPSO phases.After 510℃heat treatment,lamellae shortened,and their content decreased.Upon 8h heat treatment,block 18R LPSO phases formed at the grain boundaries while 14H LPSO lamellae disappeared.Presence of block 18R LPSO phases improved mechanical and damping properties of the alloy.The corresponding mechanisms of the influence of LPSO type and morphology on mechanical and damping capacities are discussed. 展开更多
关键词 Heat treatment LPSO phases Mechanical properties Damping capacities
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Mechanical properties and damping capacities of magnesium alloys processed by equal channel angular extrusion(ECAE) 被引量:4
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作者 吴昆 胡小石 郑明毅 《中国有色金属学会会刊:英文版》 CSCD 2005年第S2期276-279,共4页
Equal channel angular extrusion (ECAE) was applied to commercial pure magnesium and AZ91D alloy. Microstructures of these magnesium alloys before and after ECAE process were observed by optical microscopy (OM). The ul... Equal channel angular extrusion (ECAE) was applied to commercial pure magnesium and AZ91D alloy. Microstructures of these magnesium alloys before and after ECAE process were observed by optical microscopy (OM). The ultimate tensile strength of pure magnesium and AZ91D alloy processed by ECAE is about 130 and 260MPa, respectively, and it is much higher than that of the as cast alloys. The elongation of them is increased from about 2% to 8%. The strain amplitude dependence damping capacities of these magnesium alloys were investigated by dynamic mechanical analyzer (DMA). ECAE process largely decreases the damping capacities of pure magnesium from 0.033 to about 0.012 (ε=1×10 -4), but does not show obvious influence on that of AZ91D alloy, which is about 0.0015. 展开更多
关键词 pure magnesium AZ91D alloy equal channel ANGULAR extrusion DAMPING capacities MICROSTRUCTURES
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Therapeutic capacities of human and mouse skeletal muscle-derived stem cells for a long gap peripheral nerve injury 被引量:4
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作者 Tetsuro Tamaki 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第11期1811-1813,共3页
An overview of a long-gap peripheral nerve therapy:A longgap peripheral nerve transection injury is an irreparable injury to the living body,and mostly leads to permanent loss of related motor and sensory functions.In... An overview of a long-gap peripheral nerve therapy:A longgap peripheral nerve transection injury is an irreparable injury to the living body,and mostly leads to permanent loss of related motor and sensory functions.In such long gap injuries, 展开更多
关键词 Therapeutic capacities of human and mouse skeletal muscle-derived stem cells for a long gap peripheral nerve injury
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Low-temperature heat capacities of crystalline Ho(Gly)_(3)Cl_(3)·3H_(2)O from 78 to 348 K
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作者 张景楠 王辉 +3 位作者 谭志诚 刘北平 史全 童波 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第6期919-922,共4页
Heat capacities of the rare-earth complex with glycine [Ho(Gly)3Cl3·3H2O] were measured with a high-precision automatic adiabatic calorimeter over the temperature range from 78 to 348 K.In the experimental temper... Heat capacities of the rare-earth complex with glycine [Ho(Gly)3Cl3·3H2O] were measured with a high-precision automatic adiabatic calorimeter over the temperature range from 78 to 348 K.In the experimental temperature range,the heat capacities increased in a smooth and continuous manner and no phase transition or thermal anomaly occurred.Therefore,the sample was stable in the above temperature range.The values of experimental heat capacities were fitted to a polynomial equation with least square method and the thermodynamic functions,(HT-H298.15) and(ST-S298.15),were calculated. 展开更多
关键词 rare-earth complex Ho(Gly)3Cl3·3H2O low-temperature heat capacities thermodynamic functions
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Changes of Some Capacities and Failure Mode of Ni/MH Batteries During Cycling
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作者 尹鸽平 《High Technology Letters》 EI CAS 2001年第3期93-96,共4页
The changes of capacities of positive and negative electrodes, reserve capacities of charging and discharging, and the weight of batteries during cycling have been determined. The increase of the discharging reserve c... The changes of capacities of positive and negative electrodes, reserve capacities of charging and discharging, and the weight of batteries during cycling have been determined. The increase of the discharging reserve capacity due to the conjugated electrochemical reactions of the oxidation of hydrogen storage alloy is estimated. The results show that the failure mode of Ni/MH batteries developed is as follows: during the increase of cycles, the hydrogen storage alloy is oxidized continuously and the charging reserve capacity is decreased rapidly while the discharging reserve capacity is increased gradually, thus the internal pressure is increasing, first H 2 leaks out from the battery, then the mixture of H 2 and O 2. The leakage of gases and the total reaction of oxidation of the alloy consume H 2O, and the surface oxides on the alloy increase, so that the internal resistance of the battery increases. 展开更多
关键词 NI/MH BATTERY CYCLING CHANGES of RESERVE capacities Failure mode
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Impact of Vibration Models on Heat Capacities of HF Molecular System
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作者 Guo Yue Liu Ying Wu Bi Tao Liao 《Journal of Power and Energy Engineering》 2014年第9期1-7,共7页
Based on the analysis of completeness and finiteness of HF molecular vibrational levels, HF systemic vibrational heat capacity is studied with quantum statistical and full set of vibrational energy level determined AM... Based on the analysis of completeness and finiteness of HF molecular vibrational levels, HF systemic vibrational heat capacity is studied with quantum statistical and full set of vibrational energy level determined AM (algebraic method). The results show that correct vibrational description and vibrational energy level set of HF system are key factors in calculating heat capacity, HF heat capacity data determined by AM energy spectra {Eυ} are much superior to the ones of harmonic oscillator model, AM results are agreement with experiment data. 展开更多
关键词 IMPACT of VIBRATION MODELS on Heat capacities of HF MOLECULAR SYSTEM
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Antioxidant Capacities and Main Reducing Substance Contents in 110 Fruits and Vegetables Eaten in China 被引量:5
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作者 Changjin Liu Yanli Zhao +3 位作者 Xiaojing Li Jianying Jia Yanya Chen Zetian Hua 《Food and Nutrition Sciences》 2014年第4期293-307,共15页
The aim of this study was to screen strongly-antioxidant fruits and vegetables and supply practical diet guidance for the public. We used 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric-reducing antioxidant potential (FR... The aim of this study was to screen strongly-antioxidant fruits and vegetables and supply practical diet guidance for the public. We used 1,1-diphenyl-2-picrylhydrazyl (DPPH), ferric-reducing antioxidant potential (FRAP), 2,2’-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) and total reducing power (TRP) assays to investigate antioxidant activities in 110 fruits and vegetables. To analyze the correlation between antioxidant capacities and main reducing substance contents, total phenolic, flavonoid and vitamin C contents were assessed. The results showed great variation in antioxidant activity, and fifteen fruits and vegetables possessed the strongest antioxidant capacities: Toona sinensis, hawthorn, jujube, lotus root, persimmon, red plum, black plum, chilli pepper, star fruit, strawberry, blueberry, cherry, peach, pomegranate and great burdock. Total phenolic contents showed higher correlation with antioxidant capacity when using FRAP and TRP assays than when using the DPPH or ABTS assay. Phenolics and flavonoids, rather than vitamin C, contributed to antioxidant potential in most fruits and vegetables. 展开更多
关键词 ANTIOXIDANT Capacity FRUITS VEGETABLES PHENOLIC Flavonoid VITAMIN C
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Prediction and verification of heat capacities for pure ionic liquids 被引量:3
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作者 Zhengxing Dai Yifeng Chen +3 位作者 Chang Liu Xiaohua Lu Yanrong Liu Xiaoyan Ji 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第3期169-176,共8页
The heat capacity of ionic liquids is an important physical property,and experimental measuring is usually used as a common method to obtain them.Owing to the huge number of ionic liquids that can be potentially synth... The heat capacity of ionic liquids is an important physical property,and experimental measuring is usually used as a common method to obtain them.Owing to the huge number of ionic liquids that can be potentially synthesized,it is desirable to acquire theoretical predictions.In this work,the Conductor-like Screening Model for Real Solvents(COSMO-RS)was used to predict the heat capacity of pure ionic liquids,and an intensive literature survey was conducted for providing a database to verify the prediction of COSMO-RS.The survey shows that the heat capacity is available for 117 ionic liquids at temperatures ranging 77.66-520 K since 2004,and the 4025 data points in total with the values from 76.37 to 1484 J·mol^(-1)·K^(-1) have been reported.The prediction of heat capacity with COSMO-RS can only be conducted at two temperatures(298 and 323 K).The comparison with the experimental data proves the prediction reliability of COSMO-RS,and the average relative deviation(ARD)is 8.54%.Based on the predictions at two temperatures,a linear equation was obtained for each ionic liquid,and the heat capacities at other temperatures were then estimated via interpolation and extrapolation.The acquired heat capacities at other temperatures were then compared with the experimental data,and the ARD is only 9.50%.This evidences that the heat capacity of a pure ionic liquid follows a linear equation within the temperature range of study,and COSMO-RS can be used to predict the heat capacity of ionic liquids reliably. 展开更多
关键词 Ionic liquids Heat capacity COSMO-RS
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Analysis of Reliability for 3-State Device Network with Link-Capacities 被引量:2
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作者 Zhang Ying Liu Yanqiu(Department of Mathematics and Physics, Shenyang Polytechnic University,110023, P. R. China)Wang Dingwei(Department of Systems Engineering, Northeastern University,Shenyang 110023, P. R.China) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1999年第2期69-74,共6页
This paper presents a concept of the 3-state device system with link-capacity, whichcan, besides its normal operative state, assume two different failure states: an open-mode and ashorted-mode failure state. The 3-sta... This paper presents a concept of the 3-state device system with link-capacity, whichcan, besides its normal operative state, assume two different failure states: an open-mode and ashorted-mode failure state. The 3-state system reliability analysis often uses flow required andprobability of the device to compute the probability of the system with link-capacity. We use themethod of max-flow and min-cut theorem, give four theorems to reduce 3-state device network withlink-capacity reliability problems to 2-state problems. For practical, relevant network sizes (up to100 components), the algorithm is fast and efficient. 展开更多
关键词 RELIABILITY ANALYSIS 3-state system Structure FUNCTION Capacity.
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INFLUENCE OF CERIUM CONTENT ON DAMPING CAPACITIES OF AS-SPRAY DEPOSITED HIGH SILICON ALLOY ZA27 被引量:2
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作者 Liu, Yongchang Lu, Yili +1 位作者 Yang, Gencang Zhu, Zhengang 《中国有色金属学会会刊:英文版》 EI CSCD 1997年第1期112-116,共5页
INFLUENCEOFCERIUMCONTENTONDAMPINGCAPACITIESOFASSPRAYDEPOSITEDHIGHSILICONALLOYZA27①LiuYongchang,LuYili,YangG... INFLUENCEOFCERIUMCONTENTONDAMPINGCAPACITIESOFASSPRAYDEPOSITEDHIGHSILICONALLOYZA27①LiuYongchang,LuYili,YangGencang,ZhuZhengan... 展开更多
关键词 SPRAY DEPOSITION DAMPING capacity CERIUM modification
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Low-temperature heat capacities and standard molar enthalpy of formation of pyridine-2,6-dicarboxylic acid 被引量:2
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作者 杨伟伟 邸友莹 +1 位作者 孔玉霞 谭志诚 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期188-194,共7页
This paper reports that the low-temperature heat capacities of pyridine-2,6-dicarboxylic acid were measured by a precision automatic calorimeter over a temperature range from 78 K to 380 K.A polynomial equation of hea... This paper reports that the low-temperature heat capacities of pyridine-2,6-dicarboxylic acid were measured by a precision automatic calorimeter over a temperature range from 78 K to 380 K.A polynomial equation of heat capacities as a function of temperature was fitted by the least-squares method.Based on the fitted polynomial,the smoothed heat capacities and thermodynamic functions of the compound relative to the standard reference temperature 298.15 K were calculated and tabulated at intervals of 5 K.The constant-volume energy of combustion of the compound was determined by means of a precision rotating-bomb combustion calorimeter.The standard molar enthalpy of combustion of the compound was derived from the constant-volume energy of combustion.The standard molar enthalpy of formation of the compound was calculated from a combination of the datum of the standard molar enthalpy of combustion of the compound with other auxiliary thermodynamic quantities through a Hess thermochemical cycle. 展开更多
关键词 PYRIDINE-2 6-dicarboxylic acid adiabatic calorimetry low-temperature heat capacity standard molar enthalpy of formation
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INFLUENCE OF EXTRUSION ON DAMPING CAPACITIES OF AS-SPRAY DEPOSITED HIGH SILICON ALLOY ZA27 MODIFIED BY CERIUM 被引量:1
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作者 YC. Liu G.C. Yang YL. Lu and Z.G. Zhu (State Key Lab. of Solidification Processing, Northwestern Polytechnic University, Xi’an 710072, China Laboratory of Internal Friction and Defects in Solids, Chinese Academy of Science, Hefei 230031, China ) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1997年第5期437-444,共8页
The effects of cerium modification and extrusion on the resultant damping behavior and mechanical properties of the as-sprayed high silicon alloy ZA27 were investigated in an thort to develop a new functional material... The effects of cerium modification and extrusion on the resultant damping behavior and mechanical properties of the as-sprayed high silicon alloy ZA27 were investigated in an thort to develop a new functional material possessing high damping capacity and good mechanical properties. The damping capacity, as well as the rslative dynamic modulus, was tneasured at frequencies of 1 and 4 Hertz over the 30 to 200℃runge. At below 80℃ the as-sprayed materials appear to be approximately Asquency independent. Above 80℃, the,naterials becotne temperature sensitive, exhibiting the highest damping for the lowest hequency. The extruded, as-sprayed high silicon alloy ZA27 modified by cerium has the highest damping capacity and elongation values among them. The micro8tructure of the as-sprayed high silicon alloy ZA27 modified by 0. 5 wt% cerium was made up of fine lamellar eutectoid, porositg, a light dot-like phase and a polygonal silicon-rich phase. Finally, the opemtive damping tnechanisms were discussed in light of the data obtained hem characterization of microstructure and damping capacity. The high damping capacity was attributed primarily to phase interface thermoelastic damping between the lamellar phases with various substrvctures,except for the grain refinement. 展开更多
关键词 SPRAY deposition DAMPING capacity CERIUM modification EXTRUSION
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Volatile components,total phenolic compounds,and antioxidant capacities of worm-infected Gomphidius rutilus 被引量:2
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作者 Libin Sun Wei He +6 位作者 Guang Xin Pengju Cai Yin Zhang Zhiyong Zhang Yunyun Wei Bingxin Sun Xiaowen Wen 《Food Science and Human Wellness》 SCIE 2018年第2期148-155,共8页
This study evaluated the effects of worm infection on the volatile components,total phenolic compounds,and antioxidant capacities of Gomphidius rutilus.G.rutilus without worms(GW),G.rutilus infected by a small amount ... This study evaluated the effects of worm infection on the volatile components,total phenolic compounds,and antioxidant capacities of Gomphidius rutilus.G.rutilus without worms(GW),G.rutilus infected by a small amount of worms(GS;infected area<50%),and G.rutilus infected by a large amount of worms(GL;infected area>50%)were investigated.The volatile components of G.rutilus were analyzed by simultaneous distillation–extraction(SDE)and headspace solid-phase microextraction(HS-SPME)using gas chromatography–mass spectrometry(GC–MS).A total of 17 and 19 types of volatile compounds were detected,including ketones,alcohols,benzene,alkenes,aldehydes,esters,acids,and alkanes.Alcohols comprised the most abundant compound in GL,GS,and GW.The relative content of 1-octen-3-ol was the highest in all mushrooms.The concentration of eight-carbon(C8)compounds relative to the total volatile compounds varied widely,ranging from 40%(GW)to 64.34%(GS)and 84.42%(GS)and to 91.59%(GL),respectively,among the three samples.The antioxidant capability and the total phenolic contents of G.rutilus were evaluated in this study.The highest total phenolic content(TPC)of 192.23 mg GAE/g was found in GL,which differed significantly(P<0.05)from the latter two samples,whereas the lowest value of 156.11 mg GAE/g was found in GW.ABTS radical cation scavenging activity,FRAP ferric reducing antioxidant capacity(FRAP)radical scavenging activity,and oxygen radical absorbance capacity(ORAC)were investigated to screen the antioxidant properties of extracts.The contents of total phenolic compounds and their antioxidant capacities in vitro showed significant correlations(P<0.01).Among the three types of samples,the phenolic compounds of GL exhibited the highest antioxidant capacity,showing the values of 0.089 mM TE/g for ABTS,0.949 mM Fe^2+E/g for FRAP,and 1.952 M TE/g for ORAC.However,regarding the total antioxidant capacity,GS exhibited the highest antioxidant capacity,showing the values of 0.002648 mM TE/g for ABTS,0.004437 mM Fe^2+E/g for FRAP,and 0.256μM TE/g for ORAC.In conclusion,HS-SPME was more suitable for the extraction of volatile aroma components from G.rutilus.GL had the most abundant aroma components.GL had the highest TPC and antioxidant capacity compared with those of GS and GW,whereas GS showed the opposite results.Interestingly,GS was found to have the highest total antioxidant capacity in vitro.Based on these measured indicators,worm infection had no negative effect on the quality of G.rutilus.Therefore,worm-infected G.rutilus can also be consumed by humans. 展开更多
关键词 Gomphidius rutilus Worm infection Volatile components Total phenolic Antioxidant capacity
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The use of the node-based smoothed finite element method to estimate static and seismic bearing capacities of shallow strip footings 被引量:1
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作者 H.C.Nguyen T.Vo-Minh 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第1期180-196,共17页
The node-based smoothed finite element method(NS-FEM)is shortly presented for calculations of the static and seismic bearing capacities of shallow strip footings.A series of computations has been performed to assess v... The node-based smoothed finite element method(NS-FEM)is shortly presented for calculations of the static and seismic bearing capacities of shallow strip footings.A series of computations has been performed to assess variations in seismic bearing capacity factors with both horizontal and vertical seismic accelerations.Numerical results obtained agree very well with those using the slip-line method,revealing that the magnitude of the seismic bearing capacity is highly dependent upon the combinations of various directions of both components of the seismic acceleration.An upward vertical seismic acceleration reduces the seismic bearing capacity compared to the downward vertical seismic acceleration in calculations.In addition,particular emphasis is placed on a separate estimation of the effects of soil and superstructure inertia on each seismic bearing capacity component.While the effect of inertia forces arising in the soil on the seismic bearing capacity is non-trivial,and the superstructure inertia is the major contributor to reductions in the seismic bearing capacity.Both tables and charts are given for practical application to the seismic design of the foundations. 展开更多
关键词 Limit analysis Node-based smoothed finite element method(NS-FEM) Second-order cone programming(SOCP) Seismic bearing capacity Strip footing
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Reduced irreversible capacities of graphene oxide-based anodes used for lithium ion batteries via alkali treatment
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作者 Danhua Jiao Zhengwei Xie +1 位作者 Qi Wan Meizhen Qu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2019年第10期73-81,共9页
The large irreversible capacities of graphene oxide-based anodes hinder commercial applications of GO materials although the high specific capacity of it has been universally accepted. In this paper, GO was treated un... The large irreversible capacities of graphene oxide-based anodes hinder commercial applications of GO materials although the high specific capacity of it has been universally accepted. In this paper, GO was treated under alkaline condition and the composite consisting of the modified GO and graphite was used as anode for lithium ion batteries (LIBs), resulting in an improved initial coulombic efficiency. Electrochemical tests also showed that the modified GO/graphite electrode possessed 86.0% of initial coulombic efficiency, which was 15% higher than that of pristine GO/graphite electrode. The species and the content of functional groups were investigated via XPS, FTIR characterizations in detail, which certified that the ring-opening reaction of epoxides under alkaline condition could greatly reduce the irreversible capacity of GO/graphite anode, in addition, the reversible capacity was guaranteed at the same time. This modified GO/graphite electrodes in the LIBs exhibit superior rate capability and long cycle life. The uniqueness of this electrode lied in its chemical stability, which benefits from the transition of epoxide group and unstable functional groups removal. 展开更多
关键词 IRREVERSIBLE capacity Graphene OXIDE EPOXIDE group RING-OPENING reaction
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Simple phenols in tropical woods determined by UHPLC-PDA and their antioxidant capacities: an experimental design for Randall extraction using environmentally friendly solvents
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作者 Marie Bartakova Eva Dvorackova +1 位作者 Lucie Chromcova Petr Hrdlicka 《Journal of Forestry Research》 SCIE CAS CSCD 2020年第3期819-826,共8页
A comprehensive experimental design was developed to determine suitable conditions(volume, percentage of solvent, extraction temperature) for the ethanol extraction of phenolic compounds from ten tropical woody plants... A comprehensive experimental design was developed to determine suitable conditions(volume, percentage of solvent, extraction temperature) for the ethanol extraction of phenolic compounds from ten tropical woody plants. Wenge, angelim vermelho, zebrano, merbau,tigerwood, angelim pedra, jatoba, angelim amargoso,massaranduba, and doussie woods were used in experiments. The effects of three independent variables and their interactions on the yields of cinnamic and benzoic acid derivates were analyzed using UHPLC-PDA. The most significant parameters were found to be solvent percentage,extraction volume, and extraction temperature. Optimal conditions for the extraction of phenolic compound contents were an 80℃ extraction temperature, a 30 mL extraction volume, and the use of pure water as the extraction solvent. The tested species of woods contained mainly cinnamic acid derivates. Water extracts after hydrolysis contained greater amounts of cinnamic acid derivates than those extracts from non-hydrolyzed material.The total phenolics content was highest in water extracts of tigerwood, wenge and merbau;however, the extract of merbau wood was a stronger radical scavenger in ABTS?áassays: 34.11 ± 0.02 mM Trolox equivalents per g of dry extract. The main compounds possessing antioxidant activity in the extracts of vermelho wood assessed by UHPLC analysis were hydroxycinnamic acids. 展开更多
关键词 PHENOLIC compounds TROPICAL WOODS Ultrahigh-performance liquid chromatography ANTIOXIDANT capacity
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HIGH-TEMPERATURE HEAT CAPACITIES OF THE PHASES IN Y-Ba-Cu-O SYSTEM
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作者 Zhang Hengzhong Fang Zheng +1 位作者 Zhang Pingmin Chen Xinmin(Department of Chemistry,Central South University of Technology,Changsha 410083) 《中国有色金属学会会刊:英文版》 EI CSCD 1995年第4期31-35,共5页
HIGH-TEMPERATUREHEATCAPACITIESOFTHEPHASESINY-Ba-Cu-OSYSTEMZhangHengzhong;FangZheng;ZhangPingmin;ChenXinmin(D... HIGH-TEMPERATUREHEATCAPACITIESOFTHEPHASESINY-Ba-Cu-OSYSTEMZhangHengzhong;FangZheng;ZhangPingmin;ChenXinmin(DepartmentofChemis... 展开更多
关键词 HEAT capacity high-temperature DSC TG SUPERCONDUCTOR Y-BA-CU-O SYSTEM
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