The Application of Jet Grouting in Shanghai Foundation Pit Projects

Jet grouting in Shanghai can date back to late 1970s but was seldom applied in constructive projects. It was not until the construction of Metro in Shanghai in 1980s that jet grouting became widely accepted. Now it has been successfully applied in the constructions of two subway lines and basic constructions of some buildings nearby. A lot of experience has been accumulated through practice in terms of suitable conditions and situations. First, it can reduce deformation caused by excavation. When the system of braced framing in a certain geological condition cannot meet the demand of deforming control and bracing path cannot be increased, the method of enhancing resistance of passive zone of enclosing structure should be taken into consideration. Soil body strengthening of passive zone is usually a reasonable method. When problems of piping or artesian water occur, jet grouting of stabilizing foundation pit bottom can be used if method of groundwater lowering is not suitable due to environmental circumstances. Jet grouting is also employed in cut-off wall of foundation pit and entrance in shield working well

Moser–Trudinger type inequalities for the Hessian equation

AbstractThe k-Hessian equation for k⩾2 is a class of fully nonlinear partial differential equation of divergence form. A Sobolev type inequality for the k-Hessian equation was proved by the second author in 1994. In this paper, we prove the Moser–Trudinger type inequality for the k-Hessian equation

Therapeutic benefit of aripiprazole-olanzapine combination in the treatment of senile Alzheimer’s disease complicated by mental disorders

Purpose: To determine the clinical efficacy of aripiprazole-olanzapine combination treatment in elderly Alzheimer’s disease complicated with mental disorders. Methods: Ninety-two elderly patients with Alzheimer’s disease and mental disorders who were admitted to Binzhou People's Hospital, were enrolled in the study. They were randomized into control and study groups. Control group was treated with olanzapine, while the study group was treated with aripiprazole as an adjuvant therapy in addition to olanzapine. The clinical efficacy, scores on different scales (MMSE, ADAS-cog, CDR, ADL, NPI and CMAI), and incidence of adverse reactions were determined. Results: The overall degree of response was significantly higher in the study group than in the control group (p < 0.05). There were no significant differences in MMSE, ADAS-cog, CDR, ADL, NPI and CMAI scores between the two groups before treatment (p > 0.05). The MMSE score of the study group was significantly higher than that of the control group, and the scores in the other scales in the study group were significantly lower after treatment (p < 0.05). The study group had significantly lower incidence of adverse reactions than control group (p < 0.05). Conclusion: Aripiprazole-olanzapine combination has significant therapeutic benefit in the treatment of elderly Alzheimer’s disease patients complicated with mental disorders. It promotes recovery of neurological function, as well as produces a lower incidence of adverse reactions. Keywords: Aripiprazole, Olanzapine, Alzheimer’s disease, Mental disorder

Exact theory of the finite-temperature spectral function of Fermi polarons with multiple particle-hole excitations: Diagrammatic theory versus Chevy ansatz

By using both diagrammatic theory and Chevy ansatz approach, we derive an exact set of equations, which determines the spectral function of Fermi polarons with multiple particle-hole excitations at nonzero temperature. In the diagrammatic theory, we find out the complete series of Feynman diagrams for the multi-particle vertex functions, when the unregularized contact interaction strength becomes infinitesimal, a typical situation occurring in two- or three- dimensional free space. The latter Chevy ansatz approach is more widely applicable, allowing a nonzero interaction strength. We clarify the equivalence of the two approaches for an infinitesimal interaction strength and show that the variational coefficients in the Chevy ansatz are precisely the on-shell multi-particle vertex functions divided by an excitation energy. Truncated to a particular order of particle-hole excitations, our exact set of equations can be used to numerically calculate the finite-temperature polaron spectral function, once the numerical singularities in the equations are appropriately treated. As a concrete example, we calculate the finite-temperature spectral function of Fermi polarons in one-dimensional lattices, taking into account all the two-particle-hole excitations. We show that the inclusion of two-particle-hole excitations quantitatively improve the predictions on the polaron spectral function. Our results provide a useful way to solve the challenge problem of accurately predicting the finite-temperature spectral function of Fermi polarons in three-dimensional free space. In addition, our clarification of the complete set of Feynman diagrams for the multi-particle polaron vertex functions may inspire the development of more accurate diagrammatic theories of population-imbalanced strongly interacting Fermi gases, beyond the conventional many-body $T$-matrix approximation.Comment: 25 pages, 15 figures; for a brief summary of this work, see arXiv:2402.1180

Super Fermi polaron and Nagaoka ferromagnetism in a two-dimesnional square lattice

We consider the Fermi polaron problem of an impurity hopping around a two-dimensional square lattice and interacting with a sea of fermions at given filling factor. When the interaction is attractive, we find standard Fermi polaron quasiparticles, categorized as attractive polarons and repulsive polarons. When the interaction becomes repulsive, interestingly, we observe an unconventional highly-excited polaron quasiparticle, sharply peaked at the corner of the first Brillouin zone with momentum \mathbf{k}=(\pm\pi,\pm\pi). This super Fermi polaron branch arises from the dressing of the impurity's motion with holes, instead of particles of fermions. We show that super Fermi polarons become increasingly well-defined with increasing impurity-fermion repulsions and might be considered as a precursor of Nagaoka ferromagnetism, which would appear at sufficiently large repulsions and at large filling factors. We also investigate the temperature-dependence of super Fermi polarons and find that they are thermally robust against the significant increase in temperature.Comment: 11 pages, 10 figure

Microscopic many-body theory of two-dimensional coherent spectroscopy of exciton-polarons in one-dimensional materials

We have developed a microscopic many-body theory of two-dimensional coherent spectroscopy (2DCS) for a model of polarons in one-dimensional (1D) materials. Our theory accounts for contributions from all three processes: excited-state emission (ESE), ground-state bleaching (GSB), and excited-state absorption (ESA). While the ESE and GSB contributions can be accurately described using a Chevy's ansatz with one particle-hole excitation, the ESA process requires information about the many-body eigenstates involving two impurities. To calculate these double polaron states, we have extended the Chevy's ansatz with one particle-hole excitation. The validity of this ansatz was verified by comparing our results with an exact calculation using Bethe's ansatz. Our numerical results reveal that in the weak interaction limit, the ESA contribution cancels out the total ESE and GSB contributions, resulting in less significant spectral features. However, for strong interactions, the features of the ESA contribution and the combined ESE and GSB contributions remain observable in the 2DCS spectra. These features provide valuable information about the interactions between polarons. Additionally, we have investigated the mixing time dynamics, which characterize the quantum coherences of the polaron resonances. Overall, our theory provides a comprehensive framework for understanding and interpreting the 2DCS spectra of polarons in 1D materials, shedding light on their interactions and coherent dynamics