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Development of a Poly(vinyl chloride)-based Nitrate Ion-selective Electrode

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Chemical Research in Chinese Universities 2012年第6期28卷 957-962页

作者： he meng-meng YANG Hui-zhong Key Laboratory of Advanced Control in Light Industry Process Ministry of Education Jiangnan University Wuxi 214122 P. R. China

The authors developed a nitrate ion-selective electrode（ISE） based on poly（vinyl chloride）（PVC） membrane with methyltrioctylammonium nitrate as a carrier and 1-decanol as a *** performance of the nitrate-sensitive membranes was optimized by tuning the composition of *** electrode exhibits a linear response with a Nernstian slope of（52±1.0） mV per decade for the nitrate ion concentration ranging from 5.8×10-5 mol/L to 1.0 mol/*** electrode can be used to detect a low concentration of nitrate ions down to 3×10-5 mol/L in a pH range of 2.1―11.5 without any *** advantage of the electrode includes simple preparation,short response time and good *** detection performance of the novel electrode on nitrate ions has been tested for water samples.

关键词： Poly(vinyl chloride)(PVC) Methyltrioctylammonium nitrate Nitrate-selective electrode Potentiometric sensor

Traversable braneworld wormholes supported by astrophysical observations

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Frontiers of physics 2018年第1期13卷 109-118页

作者： Deng Wang Xin-he meng Theoretical Physics Division Chern Institute of Mathematics Nankai University Tianjin 300071 China Department of Physics Nankai University Tianjin 300071 China

In this study, we investigate the characteristics and properties of a traversable wormhole constrained by the current astrophysical observations in the framework of modified theories of gravity （MOG）. As a concrete case, we study traversable wormhole space-time configurations in the Dvali-Gabadadze- Porrati （DGP） braneworld scenario, which are supported by the effects of the gravity leakage of extra dimensions. We find that the wormhole space-time structure will open in terms of the 2o confidence level when we utilize the joint constraints supernovae （SNe） Ia ＋ observational Hubble parameter data （OHD）＋ Planck ＋ gravitational wave （GW） and z 〈 0.2874. Furthermore, we obtain several model-independent conclusions, such as （i） the exotic matter threading the wormholes can be divided into four classes during the evolutionary processes of the universe based on various energy conditions; （ii） we can offer a strict restriction to the local wormhole space-time structure by using the current astrophysical observations; and （iii） we can clearly identify a physical gravitational resource for the wormholes supported by astrophysical observations, namely the dark energy components of the universe or equivalent space-time curvature effects from MOG. Moreover, we find that the strong energy condition is always violated at low redshifts.

关键词： braneworld model traversable wormholes astrophysical observations

Matter Loops Corrected Modified Gravity in Palatini Formulation

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Communications in Theoretical Physics 2008年第7期50卷 275-278页

作者： meng Xin-he WANG Peng Department of Physics Nankai University Tianjin 300071 China Department of Physics and SLAC Stanford University California USA BK21 Division of Advanced Research and Education in Physics Department of Physics Hanyang University Seoul 133 791 Korea

Recently,corrections to the standard Einstein Hilbert action were proposed to explain the current cosmicacceleration in stead of introducing dark *** the Palatini formulation of those modified gravity models,thereis an important observation due to Arkani Hamed:matter loops will give rise to a correction to the modified gravityaction proportional to the Ricci scalar of the *** the presence of such a term,we show that the current formsof modified gravity models in Palatini formulation,specifically,the 1/R gravity and in R gravity,will have *** we study the possible instabilities due to the presence of phantom *** show that the strong instability inthe metric formulation of 1/R gravity indicated by Dolgov and Kawasaki will not appear and the decay timescales forthe phantom fields may be long enough for the theories to make sense as effective field *** the other hand,if wechange the sign of the modification terms to eliminate the phantoms,some other inconsistencies will arise for the variousversions of the modified gravity ***,we comment on the universal property of the Palatini formulation ofthe matter loops corrected modified gravity models and its implications.

关键词： modified gravity accelerated cosmic expansion loop correction and dark energy

Restoring cosmological concordance with axion-like early dark energy and dark matter characterized by a constant equation of state?

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Communications in Theoretical Physics 2024年第7期76卷 74-82页

作者： Yan-Hong Yao Xin-he meng School of Physics and Astronomy Sun Yatsen University 2 Daxue RoadTangjiaZhuhaiChina School of Physics Nankai University 94 Weijin RoadNankaiTianjinChina

The Hubble tension persists as a challenge in *** early dark energy(EDE)models,initially considered the most promising for alleviating the Hubble tension,fall short of addressing the issue without exacerbating other tensions,such as the S_(8)*** that a negative dark matter(DM)equation of state(EoS)parameter is conducive to reduce the value of the σ_(8)parameter,we extend the axion-like EDE model in this paper by replacing the cold dark matter(CDM)with DM characterized by a constant EoS w_(dm)(referred to as WDM hereafter).We then impose constraints on this axion-like EDE extension model,along with three other models:the axion-like EDE model,ΛWDM,and Λ*** constraints are derived from a comprehensive analysis incorporating data from the Planck 2018 cosmic microwave background,baryon acoustic oscillations,and the Pantheon compilation,as well as a prior on H_(0)(i.e.H_(0)=73.04±1.04,based on the latest local measurement by Riess et al)and a Gaussianized prior on S_(8)(i.e.S_(8)=0.766±0.017,determined through the joint analysis of KID1000+BOSS+2dLenS).We find that although the new model maintains the ability to alleviate the Hubble tension to~1.4σ,it still exacerbates the S_(8)tension to a level similar to that of the axion-like EDE model.

关键词： Hubble tension early dark energy noncold dark matter S8 tension

Modified regular black holes with time delay and 1-loop quantum correction

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Chinese Physics C 2022年第2期46卷 185-194页

作者： Yi Ling meng-he Wu Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China School of Physics University of Chinese Academy of SciencesBeijing 100049China School of Mathematics Physics and StatisticsShanghai University of Engineering ScienceShanghai 201620China Center of Application and Research of Computational Physics ShanghaiUniversity of Engineering ScienceShanghai 201620China

We develop the regular black hole solutions by incorporating the 1-loop quantum correction to the Newton potential and a time delay between an observer at the regular center and one at infinity. We define the maximal time delay between the center and the infinity by scanning the mass of black holes such that the sub-Planckian feature of the Kretschmann scalar curvature is preserved during the process of evaporation. We also compare the distinct behavior of the Kretschmann curvature for black holes with asymptotically Minkowski cores and those with asymptotically de-Sitter cores, including Bardeen and Hayward black holes. We expect that such regular black holes may provide more information about the construction of effective metrics for Planck stars.

关键词： modified regular black holes Kretschmann scalar curvature asymptotically Minkowski core

Instability of AdS black holes with lattices

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Chinese Physics C 2021年第2期45卷 548-554页

Anti-de Sitter(AdS)black holes with lattices are essential for optical conductivity studies in the holographic *** investigate the instability of these black holes that can result in the holographic description of charge density *** the presence of homogeneous axion fields,we show that the instability of AdS-Reissner-Nordström(AdS-RN)black holes is always ***,in the presence of Q-lattices,we find that the unstable region becomes the smallest in the vicinity of the critical region for the metal/insulator phase *** novel phenomenon is reminiscent of the behavior of the holographic entanglement entropy during quantum phase transitions.

关键词： gauge/gravity duality holographic gravity AdS black hole

A review on liquid sloshing hydrodynamics

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Journal of Hydrodynamics 2021年第6期33卷 1089-1104页

作者： Jin-hai Zheng Mi-An Xue Peng Dou Yu-meng he Key Laboratory of Coastal Disaster and Protection of Ministry of Education Hohai UniversityNanjing 210024China College of Harbour Coastal and Offshore EngineeringHohai UniversityNanjing 210024China

Liquid sloshing in tanks is a very complex nonlinear free surface fluid flow problem,which must be considered in most of the marine engineering problems such as naval architecture,offshore engineering and so *** liquid sloshing in large containers can damage the tank structure due to the direct liquid impacting *** also affects the capsizing process of the liquid cargo *** works on mitigating sloshing by using all kinds of the baffles were thus followed with *** layers with thinner thickness were shown to reduce the sloshing load of water in *** sloshing characteristics in tanks with different sizes were different,therefore,scaling effect of sloshing should also be *** in a tank can also be used as tuned liquid dampers(TLDs)to dampen wind,wave and flow-induced motions of floating or fixed marine *** paper present an overview on recent advances of liquid sloshing hydrodynamics including sloshing mitigation by using anti-sloshing baffle,layered fluids sloshing,scaling effect of sloshing and TLDs.

关键词： Sloshing mitigation layered fluids sloshing scaling effect of sloshing tuned liquid damper

Friedmann Cosmology with a Generalized Equation of State and Bulk Viscosity

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Communications in Theoretical Physics 2007年第2期47卷 379-384页

作者： meng Xin-he REN Jie HU Ming-Guang Department of Physics Nankai University Tianjin 300071 China

The universe content is considered as a non-perfect fluid with bulk viscosity and is described by a more general equation of state （endowed some deviation from the conventionally assumed cosmic perfect fluid model）. We assume the bulk viscosityis a linear combination of two terms： one is constant, and the other is proportional to the scalar expansion 0 = 3a/a. The equation of state is described as p = （γ - 1）p ＋ po, where po is a parameter. In this framework we demonstrate that this model can be used to explain the dark energy dominated universe, and different proper choices of the parameters may lead to three kinds of fates of the cosmological evolution： no future singularity, big rip, or Type-Ⅲ singularity as presented in IS. Nojiri, S.D. Odintsov, and S. Tsujikawa, Phys. Rev. D 71 （2005） 063004].

关键词： Friedmann cosmology equation of state bulk viscosity dark energy

Friedmann Cosmology with Bulk Viscosity:A Concrete Model for Dark Energy

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Communications in Theoretical Physics 2009年第8期52卷 377-382页

作者： meng Xin-he D0U Xu Department of Physics Nankai University Tianjin 300071 China Kavli Institute for Theoretical Physics China at the Chinese Academy of Sciences （KITPC-CAS） Beijing 100190 China

The universe content is considered as a non-perfect fluid with bulk viscosity and can be described by a general equation of state （endowed some deviation from the conventionally assumed cosmic perfect fluid model）. An explicitly bulk viscosity dark energy model is proposed to confront consistently with the current observational data sets by statistical analysis and is shown consistent with （not deviated away much from） the concordant A Cold Dark Matter （CDM） model by comparing the decelerating parameter. Also we compare our relatively simple viscosity dark energy model with a more complicated one by contrast with the concordant ACDM model and find our model improves for the viscosity dark energy model building. Finally we discuss the perspectives of dark energy probes for the coming years with observations.

关键词： dark energy cosmology bulk viscosity unification of dark matter and dark energy