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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 1105-1117页

作者： Akshay Ramesh bura B Kondraivendhan Department of Civil Engineering Sardar Vallabhbhai National Institute of TechnologySuratGujaratIndia 395007

The efiect of an innovative accelerated carbonation curing technique was evaluated on concrete containing natural zeolite powder and fine aggregate as partial replacement to alleviate the CO_(2) emission up to a certain extent from the concrete production industry and improve sequestration of CO_(2) into the concrete matrix in a stable *** accelerated carbonation curing was accomplished by subjecting the concrete specimens to 0.5 and 0.75 M concentrations of sodium bicarbonate(NaHCO_(3)) solutions up to a curing age of 180 days after the initial 28 days of normal water *** for carbonation depth,pH value,compressive strength,calcium carbonate(CaCO_(3))content,X-ray difiraction,and thermogravimetric(TGA)analyses and Fourier transform infrared spectroscopy(FtiR)were performed to measure the extent of *** obtained results showed an increment in average compressive strength for the zeolite concrete(ZLC)mixes exposed to accelerated carbonation *** ZLC mixes exposed to increasing NaHCO_(3) solution concentration and exposure period exhibited greater carbonation depth and decreased pH at each depth interval indicating higher CO_(2) sequestration within the concrete *** results obtained from the microstructural analysis(XRD,TGA,and FtiR)and CaCO_(3) content measurements confirm that the higher amount of CaCO_(3) formation provides a clear indication of the carbonation enhancement and CO_(2) sequestration within the concrete matrix and in turn contributing to the global warming reduction.

关键词： CO_(2)sequestration accelerated carbonation natural zeolite calcium carbonate

Continuous leaderless synchronization control of multiple spacecraft on SO(3)

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Astrodynamics 2021年第3期5卷 279-291页

作者： ti Chen State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 211106China

This paper presents a solution to the leaderless consensus of multiple spacecraft on SO(3)under a connected undirected *** algorithm is proposed to generate an undirected tree graph from a connected undirected communication topology.A distributed observer is designed to estimate the desired attitude and angular velocity for each spacecraft under the generated tree *** adaptive controller with a general connected undirected graph is developed to complete the synchronization *** with zero and nonzero final angular velocities are *** proofs and numerical simulations are presented to demonstrate the effectiveness of the proposed controllers.

关键词： leaderless synchronization distributed observer SO(3) adaptive controller

Property Changes of Gamma-Ray Bursts

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Chinese Physics Letters 1996年第8期13卷 637-640页

作者： LI ti-pei Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039

From analysing the third burst and transient source experiment gamma-ray burst catalog,systematic variations of average observational characteristics ofγ-ray bursts(GRBs)with a time scale of months to years are revealed,which raise a difficulty to existing models and indicate an origin of GRBs,at least partly,within the heliosphere.A possible GRB producing process is discussed.

关键词： difficulty transient origin

Conjugated Polymers as Hole Transporting Materials for Solar Cells

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Chinese Journal of Polymer Science 2020年第5期38卷 449-458,I0005页

作者： Dan ti Kun Gao Zhi-Pan Zhang Liang-ti Qu Beijing Key Laboratory of Photoelectronic/Electrophotonic Conversion Materials Key Laboratory of Cluster ScienceMinistry of EducationSchool of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

In principle,conjugated polymers can work as electron donors and thus as low-cost p-type organic semiconductors to transport holes in photovoltaic *** the booming interests in high-efficiency and low-cost solar cells to tackle global climate change and energy shortage,hole transporting materials(HTMs)based on conjugated polymers have received increasing attention in the past *** this perspective,recent advances in HTMs for a range of photovoltaic devices including dye-sensitized solar cells(DSSCs),perovskite solar cells(PSCs),and silicon(Si)/organic heterojunction solar cells(HSCs)are summarized and perspectives on their future development are also presented.

关键词： Conjugated polymers Hole transporting materials Dye-sensitized solar cells Perovskite solar cells Silicon/organic heterojunction solar cells

Effect of Wave Nonlinearity on the Instantaneous Seabed Liquefaction

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China Ocean Engineering 2024年第1期38卷 93-103页

作者： WANG Zhao-jun SUI ti-ti ZHANG Chi PAN Jun-ning Key Laboratory of Port Waterway and Sedimentation Engineering of the Ministry of TransportNanjing Hydraulic Research InstituteNanjing 210024China Key Laboratory of Coastal Disaster and Protection(Hohai University) Ministry of EducationNanjing 210098China The National Key Laboratory of Water Disaster Prevention Nanjing 210098China

The nonlinear variation of wave is commonly seen in nearshore area,and the resulting seabed response and liquefaction are of high concern to coastal *** this study,an analytical formula considering the nonlinear wave skewness and asymmetry is adopted to provide wave pressure on the seabed *** liquefaction depth attenuation coefficient and width growth coefficient are defined to quantitatively characterize the nonlinear effect of wave on seabed *** on the 2D full dynamic model of wave-induced seabed response,a detailed parametric study is carried out in order to evaluate the influence of the nonlinear variation of wave loadings on seabed ***,new empirical prediction formulas are proposed to fast predict the maximum liquefaction under nonlinear *** indicate that(1)Due to the influence of wave nonlinearity,the vertical transmission of negative pore water pressure in the seabed is hindered,and therefore,the amplitude decreases significantly.(2)In general,with the increase of wave nonlinearity,the liquefaction depth of seabed decreases *** under asymmetric and skewed wave loading,the attenuation of maximum seabed liquefaction depth is the most significant among all the nonlinear wave ***,highly skewed wave can cause the liquefaction depth of seabed greater than that under linear wave.(3)The asymmetry of wave pressure leads to the increase of liquefaction width,whereas the influence of skewedness is not significant.(4)Compared with the nonlinear waveform,seabed liquefaction is more sensitive to the variation of nonlinear degree of wave loading.

关键词： nonlinear wave seabed response seabed liquefaction numerical simulation liquefaction prediction

Polarization in Gamma-Ray Bursts Produced by Pinch Discharge

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Chinese Journal of Astronomy and Astrophysics 2005年第1期5卷 57-64页

作者： MeiWu LiChen ti-PeiLi KeyLab.ofParticleAstrophys. Inst.ofHighEnergyPhys.ChineseAcademyofSciencesBeijing100039 DepartmentofAstronomy BeijingNormalUniversityBeijing100875 KeyLab.ofParticleAstrophys. Inst.ofHighEnergyPhys.ChineseAcademyofSciencesBeijing100039／／CenterforAstrophysicsTsinghuaUniversityBeijing100084

Large-voltage, high-temperature plasma columns produced by pinch discharge can generate γ-ray flashes with energy spectra and spectral evolution consistent with what are observed in γ-ray bursts (GRBs), and the inverse Compton scattering (ICS) during the discharge process can produce high linear polarization. Our calculation indicates that the observed polarization depends on the angle between the line-of-sight to the GRB and the direction of the pinch discharge, but only weakly depends on observed γ-ray energy.

关键词： gamma-ray bursts radiation mechanism non-thermal polarization

Numerical test of scale relations for modelling coastal sandbar migration and inspiration to physical model design

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Journal of Hydrodynamics 2022年第4期34卷 700-711页

作者： Yuan Li Chi Zhang Shan-hang Chi Yun-han Yang Jian Shi ti-ti Sui State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210024China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210024China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China

Physical model experiments on sandbar migration are widely conducted in the wave flume to reveal its hydro-sediment dynamic *** an appropriate scale relation is an important part of designing a laboratory ***,evaluating the scale effect is complicated since it is impractical to design wave flume experiments based on strict geometry scales derived from the prototype beach or other laboratory ***,a process-based numerical model is used to test the Dean and Shields similitudes by comparing sandbar migration and sediment transport in different undistorted model scales using natural *** numerical model provides excellent predictions for both offshore sandbar migration on a real-world beach and onshore sandbar migration in the wave *** with previous studies,sandbar offshore migration and suspended sediment transport are similar when the Dean similitude is *** onshore migration and bedload transport can be well reproduced only if the Shields similitude is *** previous laboratory experiments of sandbar migration generally used the Dean similitude,it is found that the Shields similitude is effective and indispensable for modelling sandbar onshore migration,which will be underestimated if the Dean similitude is only *** scale relation cannot be used simultaneously for modelling both onshore and offshore sandbar migration in physical models.

关键词： Coastal sandbar migration sediment transport scale relations numerical modelling

SUSTAINABLE LAND USE PLANNING BASED ON ECOLOGICAL HEALTH——Case Study of Beiwenquan Town, Chongqing, China

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Chinese Geographical Science 2005年第2期15卷 137-144页

作者： SHAOJing-an WEIChao-fu XIEDe-ti CollegeofResourceandEnvironment SouthwestAgriculturalUniversityChongqing400716P.R.China／／ChongqingKeyLaboratoryofDigitalAgricultureChongqing400716P.R.China

This paper, taking Beiwenquan Town of Beibei, Chongqing as an example, assessed the impacts of land use on ecological health by comprehensive index method, and discussed methodological system of sustainable land use planning based on ecological health. Results indicated that: 1) From 1992 to 2002, land use changes focused on 12 patterns with the total conversion area of 92.11%, which were related to cultivated land, residential and industrial-mining area, and orchard land. Urbanization and economic reconstruction were the leading driving forces. 2) There was obvious difference of the areas of ecotypes driven by land use change in wide valley and mild slope between 1992 and 2002, while there were little or no difference in steep slope and very steep slope. 3) Both of the conditions of ecological health in 1992 and 2002 were sound, and the ecotypes focused on the types of health and sub-health. But, health ecosystem in 1992, with an area of 764.64ha, accounting for 38.51% of the total evaluation area, was better than that in 2002, with an area of 636.10ha, accounting for 34.19% of the total evaluation area. 4) The ecotypes involved into different ranges have already degenerated, due to humankind’s disturbance, while the conditions of ecological health in the same ranges in 1992, regardless of stability and reconstruction, were better than that in 2002. 5) The planning scenario based on ecological health was accorded with the practice condition of Beiwenquan Town: 388.29ha of cultivated land could meet the Beiwenquan demand of food and byproduct; 1045.26ha of forest land area, the Beiwenquan demand of ecological health; and 1004.73ha of the residential and industrial-mining area, the Beiwenquan building demand. 6) Sustainable land use planning based on ecological health had higher useful value, because it not only stood to ecological theory, but also satisfied the developmental demand of society and economy.

关键词： ecological health land use ecological evaluation land supply and demand sustainable land use planning

Autoregressive Spectral Estimation for Quasi-Periodic Oscillations

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Chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 495-507页

作者： Li Chen ti-Pei Li Department of Astronomy Beijing Normal University Beijing 100875 Center for Astrophysics Tsinghua University Beijing 100084 Key Lab. of Particle Astrophysics Inst. of High Energy Physics Chinese Academy ofSciences Beijing 100039

Modern methods of spectral estimation based on parametric time-series models are useful tools in power spectral analysis. We apply the autoregressive （AR） model to study quasi-periodic oscillations （QPOs）. An empirical formula to estimate the expectation and standard deviation of the noise AR power densities is derived, which can be used to estimate the statistical significance of an apparent QPO peak in an AR spectrum. An iterative adding-noise algorithm in AR spectral analysis is proposed and applied to studying QPOs in the X-ray binary Cir X-1.

关键词： methods: data analysis - stars: individual (Circinus X-1) - X-rays:stars

Gamma-Ray Bursts from Discharges in Plasmas

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Chinese Physics Letters 1997年第7期14卷 557-560页

作者： LI ti-pei WU Mei Institute of High Energy Physics Chinese Academy of SciencesBeijing 100039

We show that large-voltage and high-temperature pinch plasma columns can generate hard x-ray andγ-ray flashes with energy spectra and spectral evolution characteristics consistent with those observed inγ-ray bursts.

关键词： columns spectra spectral