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scaling and clogging treatment of aging tunnel drainage pipes in karst areas using eco-friendly acid agent

Journal of Rock Mechanics and Geotechnical Engineering 2023年第4期15卷 896-910页

作者： Zhipeng Xu Xuemei Wang Chunfang Zhang Dejian Zeng Changwu Liu College of Water Resource and Hydropower Sichuan UniversityChengdu610065China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu610065China College of Chemistry Sichuan UniversityChengdu610065China College of Chemistry and Environment Science Hebei UniversityBaoding071002China China Railway Eryuan Engineering Group Co.Ltd. Chengdu610031China

In karst areas,the drainage pipes of aging tunnels are prone to be clogged by precipitated carbonates,resulting in lining cracking and tunnel leaking.As a result,not only the driving safety will be deteriorated,but also the water pressure on the lining might also be elevated significantly.For the structural stability and service lifespan of old tunnels,it is of great importance to remove these precipitated carbonates in time.Traditional treatment methods are often destructive to some extent or not efficient enough.This study aims to experimentally develop an eco-friendly acid-based chemical cleaning method to remove carbonate precipitations efficiently.The proposed chemical cleaning agent is an aqueous solution with strong acidity,consisting of sulfamic acid,water,and additives.The factors affecting the cleaning efficiency include the acid solubility,temperature and flow rate of the cleaning agent,as well as additives.Elevating the solution temperature to 50C or a flow rate of no less than 0.2 m/s can improve cleaning efficiency.Although the salt effect cannot work,1 wt%of polymaleic acid as a surfactant could further promote the cleaning rate.The cleaning efficiency will increase with the flow rate in a power function.The relatively low flow rate that improves the cleaning rate considerably can avoid highpressure-induced mechanical damage to tunnel drainpipes.The waste could be easily treated to acceptable levels using commercial sewage treatment products and can also be recycled in agriculture.With the chemical cleaning,the water pressure at the arch springing of the lining will reduce with the increased radius of transverse drainpipes in a power function.The proposed acid-based cleaning method,which is highly efficient,non-or low-destructive to aging tunnels,sufficiently safe for humans,and friendly enough to the environment,will offer a promising alternative to remove the precipitated carbonates in tunnel drainpipes efficiently.

关键词： Clogging scaling Carbonate precipitation Acid treatment Water pressure on the lining Aging tunnel Karst

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scaling Laws of Heat Flux Width in the HL-2A Closed Divertor Tokamak

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Chinese Physics Letters 2022年第11期39卷 37-41页

作者：严龙文高金明苗祥淦黄治辉吴娜陈文锦吴婷王威策刘亮何小雪弋开阳何钰聂林石中兵钟武律 Southwestern Institute of Physics Chengdu 610225China

The scaling law of divertor heat flux width is one of the key topics of magnetic confinement fusion,which is almost inversely proportional to the poloidal magnetic field on some opened divertor tokamaks.This work focuses on the scaling laws of the closed divertor heat flux width in the HL-2 A tokamak under different discharge conditions,such as the Ohmic,L-and H-modes.The results indicate that there are basic similarities of the scaling laws of the heat flux width between the opened and closed divertors.However,a larger spreading width in the private flux region is found,which is relevant to a small expansion factor of the magnetic flux in the closed divertor.

关键词： tokamak magnetic scaling

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Pleiotropy Structures Plant Height and Seed Weight scaling in Barley despite Long History of Domestication and Breeding Selection

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Plant Phenomics 2023年第1期5卷 85-93页

作者： Tianhua He Tefera Tolera Angessa Chengdao Li Western Crop Genetics Alliance Agricultural SciencesCollege of ScienceHealthEngineering and EducationMurdoch UniversityMurdochWAAustralia Agriculture and Food Department of Primary Industries and Regional DevelopmentSouth PerthWAAustralia

Size scaling describes the relative growth rates of different body parts of an organism following a positive correlation.Domestication and crop breeding often target the scaling traits in the opposite directions.The genetic mechanism of the size scaling influencing the pattern of size scaling remains unexplored.Here,we revisited a diverse barley(Hordeum vulgare L.)panel with genome-wide single-nucleotide polymorphisms(SNPs)profile and the measurement of their plant height and seed weight to explore the possible genetic mechanisms that may lead to a correlation of the two traits and the influence of domestication and breeding selection on the size scaling.Plant height and seed weight are heritable and remain positively correlated in domesticated barley regardless of growth type and habit.Genomic structural equation modeling systematically evaluated the pleiotropic effect of individual SNP on the plant height and seed weight within a trait correlation network.We discovered seventeen novel SNPs(quantitative trait locus)conferring pleiotropic effect on plant height and seed weight,involving genes with function in diverse traits related to plant growth and development.Linkage disequilibrium decay analysis revealed that a considerable proportion of genetic markers associated with either plant height or seed weight are closely linked in the chromosome.We conclude that pleiotropy and genetic linkage likely form the genetic bases of plant height and seed weight scaling in barley.Our findings contribute to understanding the heritability and genetic basis of size scaling and open a new venue for seeking the underlying mechanism of allometric scaling in plants.

关键词： breeding scaling Plant

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Evolution of metabolic scaling among the tetrapod:effect of phylogeny,the geologic time of class formation,and uniformity of species within a class

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Integrative Zoology 2022年第5期17卷 904-917页

作者： Valery M.GAVRILOV Tatiana B.GOLUBEVA Andrey V.BUSHUEV Department of Vertebrate Zoology M.V.Lomonosov Moscow State UniversityMoscowRussia Zvenigorod Biological Station M.V.Lomonosov Moscow State UniversityMoscowRussia

The metabolic scaling in the animal has been discussed for over 90 years,but no consensus has been reached.Our analysis of 2126 species of vertebrates reveals a signiﬁcant allometric exponent heterogeneity.We show that classes of terrestrial vertebrates exhibit the evolution of metabolic scaling.Both the allometric coefﬁcient“a”and the allometric exponent“b”change naturally,but differently depending on the geological time of group forma-tion.The allometric coefﬁcient“a”shows the measure of the evolutionary development of systems that forms resting metabolism in animals.Endothermic classes,such as birds and mammals,have a metabolic rate that is in an order of magnitude higher than that in ectothermic classes,including amphibians and reptiles.In the terrestrial vertebrate phylogeny,weﬁnd that the metabolic scaling is characterized by 3 main allometric exponent values:b=3/4(mammals),b>3/4(ectotherms,such as amphibians and reptiles),and bscaling factor decreases depending on both the external design and the size(birds vs mammals)of the an-imal.The metabolic rate and uniformity of species within a class increase as the geological start date of for-mation of the class approaches the present time.The higher the mass-speciﬁc standard metabolic rate in the class,the slower metabolic rate grows with increasing body size in this class.Our results lay the groundwork for further exploration of the evolutionary and ecological aspects of the development of metabolic scaling in animals.

关键词： geological time metabolic rate scaling

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scaling behavior of different shapes of hysteresis loops and recoverable energy storage density in Na_(0.5)Bi_(0.5)TiO_(3), K_(0.5)Bi_(0.5)TiO_(3), and Na_(0.25)K_(0.25)Bi_(0.5)TiO_(3) ferroelectrics

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Journal of Materiomics 2022年第4期8卷 918-927页

作者： Krishnarjun Banerjee Saket Asthana Advanced Functional Materials Laboratory Department of PhysicsIndian Institute of Technology HyderabadKandiTelangana502284India

In this work,the dependency of the polarization(P)-electric field(E)loop area A of lead free ferro-electrics Na_(0.5)Bi_(0.5)TiO_(3)(NBT), K_(0.5)Bi_(0.5)TiO_(3)(KBT),and Na_(0.25)K_(0.25)Bi_(0.5)TiO_(3)(NKBT)on the amplitude(E0)of the electric field is studied.Based on the nature of the hysteresis loop with increasing E0,the lnA versus lnE0 graph is divided into three stages and the scaling exponents of each stage are estimated.In the third stage,NBT,KBT,and NKBT show different shapes of P-E loops(square,slanted and pinched,respectively).Although,almost similar slopes in the third stage are obtained from the lnA versus lnE0 graphs of KBT and NKBT,the formation of pinched P-E loop of NKBT is discussed based on the current-time curve under a complete cycle of the applied electric field.The shape of the P-E loop also affects the recoverable energy storage density(Wrec)of the material.Similar to the scaling of A,the variation of lnWrec with lnE0 of NBT,KBT and NKBT are examined.Interestingly,three stages are only noticed in the lnWrec-lnE0 curve of pinched P-E loop(NKBT),whereas lnWrec linearly increases with lnE0 for square and slanted P-E loop.Such type of behavior of Wrec of NKBT is explained based on the reversible domain switching mechanism of the pinched P-E loop.

关键词： scaling Recoverable energy storage density Lead free ferroelectric

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scaling symmetry meets topology

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Science Bulletin 2019年第5期64卷 289-290页

作者： Pengfei Zhang Hui Zhai Institute for Advanced Study Tsinghua University

In 1970,Vitaly Efimov found an interesting phenomenon in a quantum three-body problem,which is now known as the Efimov effect.Efimov found that when the two-body in teraction potential is short-ranged and is tuned to the vicinity of an s-wave resonance,an inhnite number of three-body bound states emerge and their eigenenergies En form a geometric sequence as En=-|Eo|exp(—2m/So).

关键词： scaling symmetry meets topology In 1970

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Consistent scaling Exponents at the Deconfined Quantum-Critical Point

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Chinese Physics Letters 2020年第5期37卷 93-97页

作者： Anders W.Sandvik 赵博文 Department of Physics Boston UniversityBostonMassachusetts 02215USA Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing 100190

We report a quantum Monte Carlo study of the phase transition between antiferromagnetic and valence-bond solid ground states in the square-lattice S=1/2 J-Q model.The critical correlation function of the Q terms gives a scaling dimension corresponding to the value v=0.455±0.002 of the correlation-length exponent.This value agrees with previous(less precise)results from conventional methods,e.g.,finite-size scaling of the nearcritical order parameters.We also study the Q-derivatives of the Binder cumulants of the order parameters for L2 lattices with L up to 448.The slope grows as L1/v with a value of v consistent with the scaling dimension of the Q term.There are no indications of runaway flow to a first-order phase transition.The mutually consistent estimates of v provide compelling support for a continuous deconfined quantum-critical point.

关键词： transition. confined scaling

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Stability of heterogeneous single-atom catalysts:a scaling law mapping thermodynamics to kinetics

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npj Computational Materials 2020年第1期6卷 460-466页

作者： Ya-Qiong Su Long Zhang Yifan Wang Jin-Xun Liu Valery Muravev Konstantinos Alexopoulos Ivo A.W.Filot Dionisios G.Vlachos Emiel J.M.Hensen Laboratory of Inorganic Materials and Catalysis Department of Chemical Engineering and ChemistryEindhoven University of TechnologyP.O.Box 5135600 MB EindhovenThe Netherlands Department of Chemical and Biomolecular Engineering The Delaware Energy InstituteUniversity of Delaware221 Academy St.NewarkDE 19716USA Department of Chemical Engineering University of MichiganAnn ArborMI 48109-2136USA

Heterogeneous single-atom catalysts(SACs)hold the promise of combining high catalytic performance with maximum utilization of often precious metals.We extend the current thermodynamic view of SAC stability in terms of the binding energy(E_(bind))of singlemetal atoms on a support to a kinetic(transport)one by considering the activation barrier for metal atom diffusion.A rapid computational screening approach allows predicting diffusion barriers for metal-support pairs based on Ebind of a metal atom to the support and the cohesive energy of the bulk metal(E_(c)).

关键词： kinetics thermodynamics scaling

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scaling of the Leading Response in Linear Quench Dynamics in the Quantum Ising Model

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Chinese Physics Letters 2012年第8期29卷 194-197页

作者：余咏芝王立刚顾世建林海青 Department of Physics and ITP The Chinese University of Hong KongHong Kong

We study the scaling behavior of the linear response in the quench dynamics in the one-dimensional transverse-field Ising model.It is found that the leading response of the system scales linearly with the system size.By considering the second derivative of the leading term of the response,we also found that it exhibits a non-trivial scaling behavior at the quantum critical point of the model.

关键词： model scaling Ising

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scaling study of the combustion performance of gas gas rocket injectors

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Chinese Physics B 2011年第6期20卷 293-304页

作者：汪小卫蔡国飙金平 School of Astronautics Beijing University of Aeronautics and Astronautics

To obtain the key subelements that may influence the scaling of gas-as injector combustor performance, the combustion performance subelements in a liquid propellant rocket engine combustor are initially analysed based on the results of a previous study on the scaling of a gas gas combustion fiowfield. Analysis indicates that inner wall friction loss and heat-flux loss are two key issues in gaining the scaling criterion of the combustion performance. The similarity conditions of the inner wall friction loss and heat-flux loss in a gas-gas combustion chamber are obtained by theoretical analyses. Then the theoretical scaling criterion was obtained for the combustion performance, but it proved to be impractical. The criterion conditions, the wall friction and the heat flux are further analysed in detail to obtain the specific engineering scaling criterion of the combustion performance. The results indicate that when the inner fiowfields in the combustors are similar, the combustor wall shear stress will have similar distributions qualitatively and will be directly proportional to pc0.8dt-0.2 quantitatively. In addition, the combustion peformance will remain unchanged. Furthermore, multi-element injector chambers with different geometric sizes and at different pressures are numerically simulated and the wall shear stress and combustion efficiencies are solved and compared with each other. A multi- element injector chamber is designed and hot-fire tested at several chamber pressures and the combustion performances are measured in a total of nine hot-fire tests. The numerical and experimental results verified the similarities among combustor wall shear stress and combustion performances at different chamber pressures and geometries, with the criterion applied.

关键词： scaling combustion performance subscale combustor wall friction gas-gas combustion

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