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Analytical algorithm for longitudinal deformation profile of a deep tunnel

Journal of Rock Mechanics and Geotechnical Engineering 2021年第4期13卷 845-854页

作者： Qian Fang gan Wang Fucai yu Jianming Du Key Laboratory of Urban Underground Engineering of Ministry of Education Beijing Jiaotong UniversityBeijing100044China Beijing Academy of Safety Science and Technology Beijing101101China

To investigate the longitudinal deformation profile(LDP)of a deep tunnel in non-hydrostatic condition,an analytical model is proposed in our *** this model,the problem is considered as a superposition of two partial models,and the displacement field of the second partial model is the same as that of the concerned ***,the problem can be solved by a model with simple boundary *** obtain the solutions for the stress and displacement fields of an infinite body caused by arbitrary surface tractions on the boundary of the coming tunnel(zone inside the tunnel before excavation)by integrating the extended Kelvin solution over the *** obtained stress solution is used to solve the specific surface tractions,which can satisfy the boundary conditions of the second partial model,on the boundary of the coming tunnel in an infinite ***,the specific surface tractions are substituted into the obtained displacement solution to solve the displacement on the wall and face of the ***,the LDP can also be *** proposed solution is verified by both numerical simulation and the LDP functions recommended by other *** major advantage of our analytical model is that it can consider the effects of the axial and horizontal lateral pressure *** is revealed that the horizontal lateral pressure coefficient majorly affects the LDP behind the tunnel face,while the axial lateral pressure coefficient dominates the LDP ahead of the tunnel ***,the deformation characteristics of the LDPs ahead of the face and the unexcavated core are *** axial displacements of the excavation face can be used to predict the crown displacements ahead of the face.

关键词： Deep tunnel Elastic solution Longitudinal deformation profile(LDP) Tunnel face Displacement

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Investigation of Stable C and Cl Isotope Effects of Trichloroethene and Tetrachloroethylene during Evaporation at Different Temperatures

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Journal of Earth Science 2014年第4期25卷 735-740页

作者： Tingting yu Yiqun gan Aiguo Zhou Kai yu yunde Liu School of Environmental Studies China University of Geosciences State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences

There are variations of reported isotope enrichment factors of chlorinated organic contaminants in evaporation processes. Trichloroethene （TCE） and tetrachloroethylene （PCE） were chosen to study carbon and chlorine isotope effects during evaporation at different temperatures. Equilibrium vapor-liquid carbon and chlorine isotope effects experiments were also conducted. In the equilibrium liquid-vapor system, the 13C was enriched but 37Cl was depleted in the vapor phase, being consistent with previous results. For evaporation average carbon isotope enrichment factor εc were ＋0.28‰± 0.01‰ for TCE and ＋0.56‰±0.09‰ for PCE at temperature from 20 to 26 ℃. Meanwhile, average chlorine isotope enrichment factor εCl were -1.33‰±0.21‰ for TCE and -1.00‰±0.00‰ for PCE. The results indicate that during evaporation the equilibrium isotope effect attenuates the magnitude of carbon isotope fractionation whereas enhances the chlorine isotope effect. Isotope fractionation during evaporation is determined by both equilibrium and kinetic factors. Chlorine isotope fractionation is influenced by the evaporation rate which is linked to temperature. When using stable isotope to inves- tigate the behavior of chlorinated organic contaminants in groundwater with slow biodegradation rate, the isotope fractionation resulted from evaporation should be taken into consideration. Furthermore, the environment conditions such as temperature are also factors to be considered.

关键词： chlorine isotope carbon isotope evaporation isotope fractionation chlorinated organic contaminant groundwater.

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High-performance,stable CoNi LDH@Ni foam composite membrane with innovative peroxymonosulfate activation for 2,4-dichlorophenol destruction

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Journal of Environmental Sciences 2024年第7期141卷 235-248页

作者： yu Liu Weibao Liu Xinrui gan Jiangwei Shang Xiuwen Cheng College of Chemistry and Environmental Science Xinjiang Laboratory of Phase Transitions and Microstructures of Condensed Matter PhysicsYili Normal UniversityYining 835000China Key Laboratory for Environmental Pollution Prediction and Control Gansu ProvinceCollege of Earth and Environmental SciencesLanzhou UniversityLanzhou 730000China

In this study,the cobalt-nickel layered double hydroxides(CoNi LDH)were synthesized with a variety of Co/Ni mass ratio,as *** comparison,Co1Ni3LDH presented the best peroxymonosulfate(PMS)activation efficiency for 2,4-dichlorophenol ***,CoNi LDH@Nickel foam(CoNi LDH@NF)composite membrane was constructed for enhancing the stability of catalytic ***,CoNi LDH@NF-PMS system exerted high degradation efficiency of 99.22%within 90 min for 2,4-DCP when[PMS]_(0)=0.4 g/L,Co^(1)Ni^(3)LDH@NF=2 cm×2 cm(0.2 g/L),reaction temperature=298 *** the surface morphology and structure of the catalyst,it was demonstrated that the CoNi LDH@NF composite membrane possessed abundant cavity structure,good specific surface area and sufficient active ***,·OH,SO_(4)·^(-)and^(1)O_(2)played the primary role in the CoNi LDH@NF-PMS system for 2,4-DCP decomposition,which revealed the PMS activation mechanism in CoNi LDH@NF-PMS ***,this study eliminated the stability and adaptability of CoNi LDH@NF composite membrane,proposing a new theoretical basis of PMS heterogeneous catalysts selection.

关键词： CoNi LDH@NF composite membrane Peroxymonosulfate 2,4-dichlorophenol Reactive radicals

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Leveraging Structured Information from a Passage to Generate Questions

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Tsinghua Science and Technology 2023年第3期28卷 464-474页

作者： Jian Xu yu Sun Jianhou gan Mingtao Zhou Di Wu Key Laboratory of Educational Informatization for Nationalities Yunnan Normal UniversityKunming 650500China School of Information Science and Technology Yunnan Normal UniversityKunming 650500China yunnan Key Laboratory of Smart Education Yunnan Normal UniversityKunming 650500China School of Information Engineering Qujing Normal UniversityQujing 655011China

Question Generation(QG)is the task of utilizing Artificial Intelligence(AI)technology to generate questions that can be answered by a span of text within a given *** research on QG in the educational field struggles with two challenges:the mainstream QG models based on seq-to-seq fail to utilize the structured information from the passage;the other is the lack of specialized educational QG *** address the challenges,a specialized QG dataset,reading comprehension dataset from examinations for QG(named RACE4QG),is reconstructed by applying a new answer tagging approach and a data-filtering strategy to the RACE ***,an end-to-end QG model,which can exploit the intra-and inter-sentence information to generate better questions,is *** our model,the encoder utilizes a Gated Recurrent Units(GRU)network,which takes the concatenation of word embedding,answer tagging,and Graph Attention neTworks(GAT)embedding as *** hidden states of the GRU are operated with a gated self-attention to obtain the final passage-answer representation,which will be fed to the *** show that our model outperforms baselines on automatic metrics and human ***,the model improves the baseline by 0.44,1.32,and 1.34 on BLEU-4,ROUGE-L,and METEOR metrics,respectively,indicating the effectivity and reliability of our *** gap with human expectations also reflects the research potential.

关键词： automatic Question Generation(QG) RACE4QG dataset Answer-Oriented GAT(AO-GAT) attention mechanism structured information

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Colloidal AgCl induced-growth of thorny gold nanoparticles and their SERS activity

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Chinese Chemical Letters 2019年第6期30卷 1266-1268页

作者： Shuai Zeng hong yuan Lin gan Jin Huang Key Laboratory of Pesticide and Chemical Biology of Ministry of Education College of Chemistry Central China Normal University Wuhan 430079 China Chongqing Key Laboratory of Soft-Matter Material Chemistry and Function Manufacturing School of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China

In this paper,we exploited a unique procedure for obtaining thorny gold nanoparticles(Au NPs)with controllable length of thorns without using seeds and surfacta nts.A larger number of Ag+ions was added into the reaction system containing with HAuCI4 and NH2 OH·HCl,so as to forming colloidal *** could induce the growth of thorny Au *** morphology of Au NPs changed from short-thorns,longthorns to no-thorns,as the amount of AgNO3 *** obtained Au NPs exhibited shapedetermined surface-enhanced Raman spectroscopy(SERS)activity toward rhodamine 6 G(R6 G);indicating their potential for use in SERS-based detections and analysis.

关键词： Thorny nanoparticles Gold Colloidal AgCl SERS Controllable growth

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Evaluation of regional water resources carrying capacity based on binary index method and reduction index method

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Water Science and Engineering 2019年第4期12卷 263-273页

作者： hong-yuan Fang Sheng-wei gan Chen-ying Xue College of Hydraulic Science and Engineering Yangzhou UniversityYangzhou 225009China Taihu Lake Basin Hydrological and Water Resources Monitoring Center Wuxi 214024China

Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereafter referred to as the Technical Outline),this paper elaborates on the collection and sorting of the basic data of water resources conditions,water resources development and utilization status,social and economic development in basins,analysis and examination of integrity,consistency,normativeness,and rationality of the basic data,and the necessity of WRCC *** paper also describes the technique of evaluating the WRCC in prefecture-level cities and city-level administrative divisions in the District of the Taihu Lake Basin,which is composed of the Taihu Lake Basin and the Southeastern River *** evaluation process combines the binary index evaluation method and reduction index evaluation *** former,recommended by the Technical Outline,uses the total water use and the amount of exploited groundwater as evaluation indices,showing stronger operability,while the latter is developed by simplifying and optimizing the comprehensive index system with greater systematicness and *** mutual validation and adjustment of the results of the above-mentioned two evaluation methods indicate that the WRCC of the District of the Taihu Lake Basin is overloaded in general because some prefecture-level cities and city-level administrative divisions in the Taihu Lake Basin and the Southeastern River Basin are in a severely overloaded *** order to explain this conclusion,this paper analyzes the causes of WRCC overloading from the aspects of basin water environment,water resources development and utilization,water resources regulation and control ability,water resources utilization efficiency,and water resources management.

关键词： Water resources carrying capacity(WRCC) Evaluation Binary index method Reduction index method Prefecture-level cities and city-level administrative divisions

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A new species of the genus Amolops(Anura:Ranidae)from yunnan,China

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Zoological Research 2020年第2期41卷 188-193页

作者： yu-Lu gan Guo-Hua yu Zheng-Jun Wu Key Laboratory of Ecology of Rare and Endangered Species and Environmental Protection(Guangxi Normal University) Ministry of EducationGuilinGuangxi 541004China Guangxi Key Laboratory of Rare and Endangered Animal Ecology College of Life ScienceGuangxi Normal UniversityGuilinGuangxi 541004China

DEAR EDITOR,A new species of the genus Amolops,Amolops tuanjieensis ***.,is described from yunnan,*** new species can be distinguished by the following characters:dorsolateral folds present;dorsal and ventral surfaces smooth;top of head and dorsum brown-red with irregular gray and dark spots;flank green;side of head black,from tip of snout,diffusing posteriorly to axilla,continuing as black streak below edge of dorsolateral fold;SVL 39.5-40.4 mm in males,56.8-60.7 mm in females;tympanum distinct;supratympanic fold indistinct;vomerine teeth in two oblique rows between choanae,closer to each other than choanae;vocal sacs present;nuptial pads present;outer metatarsal tubercle absent,supernumerary tubercles absent;all fingertips expanded into discs;limbs dorsally brown with dark brown bars and irregular dark brown blotches.

关键词： black closer brown

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Enhanced electrochemical oxidation of phenol by introducing ferric ions and UV radiation

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Journal of Environmental Sciences 2008年第11期20卷 1386-1391页

作者： MAO, Xuhui WEI, Lin hong, Song ZHU, Hua LIN, An gan, Fuxing School of Resource and Environmental Science Environmental Engineering Department Wuhan University Wuhan 430079 China

The mineralization of phenol in aerated electrochemical oxidation has been *** results show that a cathodic Fenton process can occur when the Ti-0.3Mo-0.8Ni alloy material is used as cathode in solution containing ferric or ferrous ions; moreover,the reinforcement of cathodic Fenton process on the total organic carbon (TOC) removal rate of phenol is quite *** the metallic ions investigated,the ferric ion is the best catalyst for the electrochemical mineralization of phenol at initial...

关键词： mineralization phenol electrochemical oxidation cathodic Fenton process UV radiation

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Free control of far-field scattering angle of transmission terahertz wave using multilayer split-ring resonators'metasurfaces

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Frontiers of physics 2020年第6期15卷 125-132页

作者： Ying Tian Xufeng Jing Haiyong gan Chenxia Li Zhi hong Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China National Institute of Metrology Beijing 102200China

To enhance transmission eficiency of Pancharatnam Berry(PB)phase metasurfaces,multilayer split-ring resonators were proposed to develop encoding *** per the generalized Snell's law,the deflection angle of the PB phase encoding metasurfaces depends on the metasurface period's ***,it is impossible to design an infinitesimal metasurface unit;consequently,the continuous transmission scattering angle cannot be *** digital signal processing,this study introduces the Fourier convolution principle on encoding metasurface sequences to freely control the trausmitted scattering *** addition and subtraction operations between two diferent encoding sequences were then performed to achieve the continuous variation of the scattering ***,we established that the Fourier convolution principle can be applied to the checkerboard coded metasur-faces.

关键词： metamaterial metasurface scattering Fourier convolution

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Mechanism of Bragg Diffraction-Assisted Light Extraction in gan-based Light-Emitting Diodes Based on a Self-Consistent Model

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Communications in Theoretical Physics 2009年第9期52卷 545-548页

作者： LIU Wen-De gan Zi-Zhao National Institute of Metrology Beijing 100013 China School of Physics and State Key Laboratory for Artificial Microstructures and Mesoscopic Physics Peking University Beijing 100871 China

By introducing the distribution of the light energy density in gan-based light-emitting diode (LED),theLED model based on the incoherent regime and the light extraction efficiency are *** energy density asa function of the angle of incidence is calculated to demonstrate the mechanism of the light *** deviationbetween the tendencies of the transmissivity of the output layer and the extraction efficiency is also demonstrated.

关键词： light-emitting diodes extraction efficiency Bragg diffraction photonic crystals

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