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In the following sub-sections, studies of solar-heliospheric effects on cosmic rays, investigating a possible link between cosmic ray flux and Earth’s climate, and detection of MeV-range γ-rays from thunderstorms with the data from LHAASO will be discussed; geophysical research with environmental neutrons will be introduced, and some Monte Carlo simulation results about effects of thunderstorm electric fields on LHAASO observations of cosmic rays will be given.

The mechanical property of steel reinforced PP ECC columns under reverse cyclic load is investigated and results are presented in this paper. The influence of reinforcement ratio, curing age and volume fraction of PP fiber on load bearing capacity, energy dissipation and stiffness degradation is investigated. The results highlighted the positive contribution of PP ECC to enhance strength and energy dissipation capacity which is important to evaluate the performance of structures subjected to reverse cyclic loads. According to the experimental study on mechanical behavior of steel reinforced PP ECC columns under reverse cyclic loading, the formula of model parameters related to reinforcement ratio are proposed，it is founded that the restoring force model established is of a certain degree of adaptability.

A large high altitude air shower observatory (LHAASO) located at Daocheng in Sichuan province, China, with an altitude up to 4410 m above the sea level, takes the function of hybrid technology to detect cosmic rays. It is composed of three sub-arrays: a 1.3 km2 ground-based particle detector array (KM2A) for γ-ray astronomy and cosmic ray physics, a 78000 m2 water Cherenkov detector array (WCDA) for γ-ray astronomy, and 18 wide field-of-view air Cherenkov/fluorescence telescopes array (WFCTA) for cosmic ray physics. As the major array of LHAASO, KM2A is composed of 5195 electromagnetic particle detectors (EDs, each with 1 m2) and 1188 muon detectors (MDs, each with 36 m2). In the ground-based experiments, there are two common independent data acquisition systems, corresponding to the shower and scaler operation modes. Up to now, the KM2A array operates only in shower mode with the primary energy threshold of about 10 TeV. In the scaler mode, it is not necessary for too many detectors to be hit at the same time. The energy threshold of the experiment can be greatly lowered. In order to learn more about the scaler mode in LHAASO-KM2A, we adopt the CORSIKA 7.5700 to study the cascade processes of extensive air showers in the atmosphere, and employ the G4KM2A (based on Geant4) to simulate the detector responses. The KM2A-ED array is divided into dozens of clusters. For one cluster (composed of 64 EDs), the event rates of showers having a number of fired EDs ≥ 1, 2, 3, 4 (in a time coincidence of 100 ns) are recorded. The average rates of the four multiplicities are ~88 kHz, ~1400 Hz, ~220 Hz, and ~110 Hz, respectively. The particle multiplicities m ≥ 3 are almost completely due to cosmic ray secondary particles. The corresponding primary energies and effective areas are also given in this paper. According to our simulations, the energy threshold of the scaler mode can be lowered to 100 GeV, and the effective areas reach up to ~100 m2. The simulation results in this work are helpful in the online triggering with the scaler mode, and provide information for the subsequent data analysis in LHAASO-KM2A.

Considering the baryon octet in the framework of relativistic mean field (RMF) theory, and the entropy per baryon is selected to be 1 or 2, we investigate the entropy effect on the protostar properties of the massive neutron star PSR J0348+0432. One set of coupling constants GL85 in the RMF are selected to reproduce the mass of PSR J0348+0432 at zero temperature, and then the parameter set is extended to calculate the properties of the massive protoneutron star with the entropy per baryon S = 1 or S = 2. It is found that more hyperons will occur in the protoneutron star than that in the zero-temperature neutron star, the temperature in the protoneutron star increases with the increase of density from surface to interior, and the occurrence of hyperons will reduce the interior temperature. Meanwhile, the entropy causes the increase of the mass of massive protoneutron star, and this effect exceeds that of hyperons to decrease the mass of massive neutron star. The entropy also brings on the increase of the radius of protoneutron star. In other words, the cooling of protoneutron star is a contraction process of stellar object.

Magnetar is a kind of pulsar powered by magnetic field energy. Part of the X-ray luminosities of magnetars in quiescence have a thermal origin and can be fitted by a blackbody spectrum with temperature kT ～ 0.2－0.6 keV, much higher than the typical values for rotation-powered pulsars. The observation and theoretical study of magnetar are one of hot topics in the field of pulsar research. The activity and emission characteristics of magnetar can be attributed to internal superhigh magnetic field. According to the work of WGW19 and combining with the equation of state, we first calculate the electric conductivity of the crust under a strong magnetic field, and then calculate the toroidal magnetic field decay rate and magnetic energy decay rate by using an eigenvalue equation of toroidal magnetic field decay and considering the effect of general relativity. We reinvestigate the LX-Lrot relationship of 22 magnetars with persistent soft X-ray luminosities and obtain two new fitting formulas on LX-Lrot. We find that for the magnetars with LX < Lrot, the soft X-ray radiations may originate from their rotational energy loss rate, or from magneto-sphere flow and particle wind heating. For the magnetars with LX > Lrot, the Ohmic decay of crustal toroidal magnetic fields can provide their observed isotropic soft X-ray radiation and maintain higher thermal temperature.As for the initial dipole magnetic fields of magnetars, we mainly refer to the rersearch by Viganò et al. (Viganò D, Rea N, Pons J A, Perna R, Aguilera D N, Miralles J A 2013 Mon. Not. R. Astron. Soc. 434 123), because they first proposed the up-dated neutron star magneto-thermal evolution model, which can successfully explain the X-ray radiation and cooling mechanism of young pulsars including magnetars and high-magnetic field pulsars. Objectively speaking, as to the decay of toroidal magnetic fields, there are some differences between our theoretical calculations of magnetic energy release rates and the actual situation of magnetic field decay in magnetars, this is because the estimate of initial dipolar magnetic field, true age and the thickness of inner crust of a magnetar are somewhat uncertain. In addition, due to the interstellar-medium’s absorptions to soft X-ray and the uncertainties of distance estimations, the observed soft X-ray luminosities of magnetars have certain deviations. With the continuous improvement of observation, equipment and methods, as well as the in-depth development of theoretical research, our model will be further improved, and the theoretical results are better accordant with the high-energy observation of magnetars.We also discuss other possible anisotropy origins of soft X-ray fluxes of magnetars, such as the formation of magnetic spots and thermoplastic flow wave heating in the polar cap. Although anisotropic heating mechanisms are different from Ohmic decay, all of them require that there exist strong toroidal magnetic fields inside a magnetar. However, the anisotropic heating mechanisms require higher toroidal multipole fields inside a magnetar (such as magnetic octupole field) and are related to complex Hall drift: these may be our research subjects in the future.

By using the solar magnetic field data of Wilcox Observatory from 1975 to 2010, the short-time periodicities of solar mean magnetic fields during solar maximum and minimum years are analyzed. The results reveal that the solar magnetic fields mainly exhibit the approximate periods of 9 d, 13 d, and 27 d. During maximal solar activity the period about 27 d is most conspicuous, while during minimal solar activity the most evident period is approximately 13.5 d (except the solar minimum in the years 1984-1986). These results imply that solar active regions exhibit evidently different distributions in the periods of maxima and minima of solar activity.

Moment-deformation curves of square steel tube filled with steel reinforced concrete subjected to bending load were simulated by the ABAQUS software. Calculated and experimental curves agreed well with each other. Through studying further the calculated member, the behavior of materials subjected to moment is given. Finally, flexural capacity formula of square steel tube filled with cross steel reinforced concrete is proposed.

Integrated structural and materials design (ISMD) represents a new design approach that combines materials and structural engineering for the purpose of more effectively achieving targeted structur...

The influences of σ* and Φ mesons, temperature and coupling constants of nucleons on the moment of inertia of the proto neutron star (PNS) are examined in the framework of relativistic mean field theory for the baryon octet {n, p, Λ, Σ−, Σ0, Σ+, Ξ−, Ξ0} system. It is found that, compared with that without considering σ* and Φ mesons, the moment of inertia decreases. It is also found that the higher the temperature, the larger the incompressibility and symmetry energy coefficient, and the larger the moment of inertia of a PNS. The influence of temperature and coupling constants of the nucleons on the moment of inertia of a PNS is larger than that of the σ* and Φ mesons.

Self-healing of ECC (Engineered Cementitious Composites) subjected to cyclic wetting and drying regimes is investigated in this paper. ECC structures subjected to outdoor environmental conditions such as wind and rain runoff can be simulated by accelerated test method of wetting and drying cycles. Uniaxial tensile tests of ECC M45 and ECC 2.8FA specimen are conducted respectively. It is found that crack width of ECC 2.8FA is around 10 μm with increased amount of fly ash, while the crack width of ECC M45 is around 100 μm. New insights about the microstructure and chemical composition analysis of ECC specimens initially cracked to 2% strain and then self-healed under wet-dry cycles are presented.

In this paper , white ECC design framework – scale linking which represents a holistic approach in composite design accounting for the interaction between the fiber, matrix, and interface are proposed. New white ECC showing pseudo strain hardening behavior with over 1.3% of strain capacity under tension are produced. Uniaxial tensile tests and single fiber pullout test of PVA white ECC are conducted to quantify the interfacial bond properties of white ECC. It is shown that lower frictional bond in white ECC may be attributed to the absence of fly ash in white ECC mix design. The mechanical performance of white ECC can be further enhanced by improving fiber bridging capacity.

A new kind of quantum optical state, photon-added and -subtracted displaced Fock states, is introduced by applying the inverse of bosonic creation and annihilation operators to displaced Fock states. The quantum statistical properties of these states are investigated by numerical methods. Numerical results indicate that these states reveal some interesting non-classical properties, such as anti-bunching effects, sub-Poisson distributions and negativities of their Wigner functions.

The fidelity of the generated Schrodinger Cat state (SCS) of a single trapped ion in the Lamb–Dicke approximation is discussed. The results show that the fidelity significantly decreases with the values of Lamb–Dicke parameter η and coherent state amplitude α increasing. For η = 0.20 and α = 3, the typical values of experimental parameters, the fidelity is rather low (30%). A scheme for generating the SCS is proposed without making the Lamb–Dike approximation in laser–ion interaction, and the fidelity of the generated SCS is about 99% for the typical values of experimental Lamb–Dicke parameters.

The report of Lambros and Rosakis [(1995) J Mech Phys Solids 43(2): 169–188] has focused attention on steady-state transonic interfacial crack growth accounting for the phenomenon of crack face contact in elastic/rigid bimaterial but could not handle issues relating to energy transmission across the interface. The present paper attempts to provide a complete explicit expression of the asymptotic fields induced by transonically propagating interfacial crack in elastic/elastic bimaterial for in-plane case. The energy distribution on the contact area, crack tip and two singular characteristic lines is analysed thoroughly and compared with the dynamic separated J-integrals. The length of the contact zone is also discussed briefly by establishing energy fracture criterion that satisfies contact condition. The two-dimensional in-plane asymptotic deformation field surrounding the contact area of a crack propagating transonically along an elastic/elastic bimaterial interface is observed and discussed thoroughly.

The influence of trapped neutrinos on the proto-neutron star is studied in the framework of relativistic mean-field theory. The results show that trapped neutrinos increase proton fraction and make the equation of state of neutron star matter softer when neglecting hyperonic freedom, while suppress the appearance of hyperons and make the equation of state stiffer when including hyperons in the protoneutron star. The maximum mass, compared with cold neutron star which is in beta equilibrium, decreases by 0.06M⊙ for non-strange protoneutron star while increases by 0.21M⊙ for protoneutron star with hyperons when the relative number of trapped neutrino is 0.4.

First, the near-tip stress and electric displacement fields are analytically solved for a dynamically propagating interfacial crack in a piezoelectric bimaterial. Second, from the rate formulation of the energy balance in a piezoelectric material, the path independent dynamic J integral is derived, which has the physical significance of the energy release rate. Using the present near-tip analytical solutions, the relationships between the dynamic J integral and the stress and electric displacement intensity factors are also obtained. It is shown that the path independent dynamic J integral contains the static J integral and the dynamic J integral for elastic materials, and static J integral for piezoelectric materials as special cases. Third, for an interfacial crack in a piezoelectric bimaterial, the path independent separated dynamic J integrals are derived, which have the physical significance of energy flow rates into the propagating interfacial crack tip from the individual material sides or, equivalently, the separated dynamic energy release rates. Fourth, to accurately evaluate mixed-mode stress and electric displacement intensity factors, the component separation method of the dynamic J integral is developed. Finally, the finite element analyses of a static stationary interfacial crack in a piezoelectric bimaterial subject to mechanical, electrical and combined loading are carried out to demonstrate the applicability of the generalized (dynamic) J integral and the separated J integral, and the component separation method.

The elastic stress field for an ellipsoidal inhomogeneous inclusion in one of two perfectly bonded semi-infinite solids subjected to external stress is investigated by the modified equivalent inclusion method. Using the general solution for the inhomogeneous inclusion in bimaterial expressed in terms of Garlerkin stress vectors, the potential functions to solve the problem are obtained. Numerical examples are given to show the traction force distributions on the boundary of the ellipsoidal inhomogeneous inclusion that have different inclined angles with the interface using a computer program developed by the authors. This research is meaningful for fracture of inclusions.

In the framework of the extended relativistic mean-field theory with hyperons, the properties of neutron star matter have been investigated. It is, found that at a density of four to five times that of nuclear matter saturation density po, a neutron star will become a hyperon star. This transition is strongly influenced by the coupling constants of hyperons to mesons and a different parameter set. For a given parameter set, a minimum transition baryon density exists when the hyperon coupling ratios satisfy x(H sigma) = x(H omega) = x(H rho) = 0.65 or x(H sigma) = x(H omega) = 0.62,x(H rho) = 0.7.

The equations of state of the neutron star matter are calculated in the relativistic mean-field approximation with different hyperon coupling constants. The properties of neutron stars are studied by solving the Oppenheimer-Volkoff equation. It manifests the properties of neutron stars - change explicitly as different hyperon coupling constants are concerned.

Engineered Cementitious Composites (ECCs) are novel cement-based ultraductile materials which is crack resistant and undergoes strain hardening when loaded in tension. In particular, the material is piezoresistive with changes in electrical resistance correlated with mechanical strain. The unique electrical properties of ECC render them a smart material capable of measuring strain and the evolution of structural damage. In this study, the conductivity of the material prior to loading was quantified. The piezoresistive property of ECC structural specimens are exploited to directly measure levels of cracking pattern and tensile strain. Changes in ECC electrical resistance are measured using a four-probe direct-current (DC) resistance test as specimens are monotonically loaded in tension. The change in piezoresistivity correlates the cracking and strain in the ECC matrix and results in a nonlinear change in the material conductivity.

Using a new set of nucleon coupling constants CZ11 the properties of a proto neutron star are examined within the framework of the relativistic mean-field theory for the baryon octet system. It is found that the relative number density of Λ, Ξ−, and Ξ0 for CZ11 are all smaller than those for GL97 and for both CZ11 and GL97, Σ−, Σ0, and Σ+ do not appear. It is also found that the pressure and the maximum mass for CZ11 are all smaller than those for GL97. The maximum mass for CZ11 decreases by approximately 9 percent compared with that for GL97.

By applying the bosonic creation operator to squeezed vacuum states, this paper introduces a new kind of quantum states: photon-added squeezed vacuum states. It also presents an experimental approach to prepare these states, and investigates their quantum statistical properties by the numerical method. The results indicate that these states reveal some interesting non-classical properties, such as anti-bunching effects, squeezing effects and negativities of the relevant Wigner functions.