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The psychological crises of university students are an important factor affecting the security and stability of colleges and universities. Against the background of school governance, the definition and characteristics of college students' psychological crisis events should be correctly understood and the legal risks clearly classified to help prevent crisis incidents. Legal risks have important practical significance. The author starts with the definition of college students' psychological crisis events and divides the characteristics into two parts: cause diversity and result sensitivity. The legal risks associated with the process are clearly divided into civil, administrative and procedural legal risks, which are specifically manifested in the duty of care in the prevention and response stages of the safety responsibility of colleges and universities. In the process, is there any infringement of privacy violations, and when an incident occurs, does the university take timely and positive measures and pay attention to protecting citizens' legitimate rights and interests during the emergency response process? Are statutory after-care obligations such as diversion and guidance covered in the aftermath phase? Are students provided with reasonable and legitimate complaint channels?

In the article, we are concerned with the three-dimensional anisotropic Boussinesq equations with the velocity dissipation in x2{x}_{2} and x3{x}_{3} directions and the thermal diffusion in only x3{x}_{3} direction. When the spatial domain is the whole space R3{{\mathbb{R}}}^{3}, the global well-posedness and stability problem for the partially dissipated Boussinesq system remain the extremely challenging open problems. Attention here focuses on the periodic domain Ω=R×T2\Omega ={\mathbb{R}}\times {{\mathbb{T}}}^{2}. We aim at establishing the stability for the problem of perturbations near hydrostatic equilibrium and the large-time behavior of the perturbed solution. We first obtain the global existence of some symmetric fluids in H2(Ω){H}^{2}\left(\Omega ) for small initial data. Then the exponential decay rates for the oscillations u˜\widetilde{u} and θ\theta in H1(Ω){H}^{1}\left(\Omega ) and the homogeneous Sobolev space Hv2˙(Ω)\dot{{H}_{v}^{2}}\left(\Omega ) are also shown. The proof is based on a key observation that we can decompose the velocity uu into the average u¯\overline{u} on T2{{\mathbb{T}}}^{2} and the corresponding oscillation u˜\widetilde{u}. This enables us to establish the strong Poincaré-type inequalities on u˜\widetilde{u}, u3,θ{u}_{3},\theta and some anisotropic inequalities, which ensure the establishment of the closed priori estimates. In addition, we also prove the oscillations in one direction u˜(2),u˜(3){\widetilde{u}}^{\left(2)},{\widetilde{u}}^{\left(3)} in H1(Ω){H}^{1}\left(\Omega ) decay to zero exponentially.

This paper aims to find a desirable new thickener for producing lithium grease. To this end, a lithium grease was prepared using self-made 9,10-dihydroxystearic acid (DHSA) as the thickener. Then, the properties of the DHSALi-based grease were compared with the traditional lithium grease prepared from 12-hydroxystearic acid (HSA). Additionally, the differences between the two greases were discussed considering molecular structure and grease-oil gel dispersion. The results show that the DHSALi-based grease outperformed the traditional grease in terms of shear stability, consistency, dropping point, colloidal stability, wear resistance and antifriction property, despite its poor shear stability. The research proves that DHSALi is a desirable raw material of grease thickener.