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This paper analyzes the cultural tourism resources of Hainan Province from both qualitative and quantitative perspectives. There are two types of cultural tourism resources: landscape cultural tourism resources and social humanities tourism resources. Based on the input-output theory and input elements such as labor and capital in the production function, combined with the principles of scientific, systematic, and availability of index selection, an evaluation index system for the utilization efficiency of cultural tourism resources in Hainan Province is constructed. The entropy value method is used to determine the weights of Hainan Province's cultural tourism resources, and the comprehensive scores of Hainan Province's cultural tourism cities and counties are calculated and taken as the endowment value of tourism resources. With the advantage of the DEA method, the cultural tourism resources of Hainan Province are further measured using the DEA method with the Malmquist index model. The input indicators for Hainan Province's cultural tourism resources are infrastructure input (23.54%), cultural resources (21.05%), labor input (19.88%), capital input (19.84%), and information technology support (15.69%). In terms of the overall mean value of the IT efficiency measurement for the tourism industry in Sanya, the IT efficiency of all cities and counties fluctuates between 0.85 and 1, with insignificant differences. During the measurement period, the maximum value appeared in 2017 and 2022, indicating that the information technology conditions and management level of Sanya's tourism industry are in an optimal state in general during this period. [ABSTRACT FROM AUTHOR]

Enhancing the flame retardancy with minimal impact on the mechanical and thermal performances of polymers remains a challenge. This study synthesized a phosphorus/nitrogen‐containing silane compound (D) using polyformaldehyde, KH‐550, and 9,10‐dihydro‐9‐oxa‐10‐phosphaphenanthrene‐10‐oxide (DOPO) as raw materials through the Kabachnik‐Fields reaction. After that, D was grafted onto the surface of graphene after hydrothermal treatment to obtain a nano hybrid flame retardant (D‐GR). And D‐GR/EP composites exhibited good flame resistance (LOI = 30.1% and UL‐94 reaches the V‐1 rating) even if the load on D‐GR was 1 wt%. Indeed, the total heat release, the peak heat release rate (PHRR), and the total smoke release of 1% D‐GR/EP dropped by 13.54%, 28.62%, and 44.32%, respectively, in comparison to pure EP. The mechanical performance of 1% D‐GR/EP was effectively maintained, as indicated by the results of impact, tensile and flexural tests. A systematic evaluation indicated that the accession of D‐GR effectively inhibited smoke and heat releases that are ascribed to the synergistic effect of phosphorus/nitrogen‐containing silane compound and graphene. In this study, a facile method was provided for the synthesis of halogen‐free flame‐retardant epoxy composites with superior performances. The combustion products of the as‐prepared composites complied with green and environmental protection standards. [ABSTRACT FROM AUTHOR]

A quadratic finite volume (FV) method for steady‐state Riesz space‐fractional diffusion equations (sFDEs) with variable diffusivity coefficient is developed using piecewise quadratic basis functions, and a resulting linear algebra system with two‐by‐two block‐type Toeplitz‐like coefficient matrix is formulated. It is proved that the method requires a minimum memory of order O(N), where N is the number of spatial partitions. Moreover, as two of the produced Toeplitz‐like submatrices are not square, a new fast nonsquare Toeplitz‐like matrix‐vector product is specially designed, which requires an almost linear computational complexity of order O(Nlog2N). Then, a fast version of biconjugate gradient stabilized (BiCGSTAB) solution algorithm, named FBiCGSTAB, is proposed for the FV scheme. The FV method combined with Crank‐Nicolson (CN) time discretization is applied to solve time‐dependent sFDEs, and an efficient CN‐FV scheme is developed and analyzed. Finally, numerical results are presented to show the utility of the fast FV and fast CN‐FV methods. [ABSTRACT FROM AUTHOR]

In structures with special geometry lattices, variations in stacking sequences are ubiquitous, yielding many novel structures and functionalities. Despite a wealth of intriguing properties and wide-ranging applications, there remains a considerable gap in understanding the correlation between special geometry lattices and functionalities in borides. Here, we design and synthesize a new superconducting boride Nb 2 IrB 2 , with a body-centered orthorhombic structure, consisting of alternating two-dimensional [Nb-Ir-Nb] triple-triangular-lattice-layers and B fragment layers. Advanced aberration-corrected scanning transmission electron microscopy observations show variable stacking configurations between [Nb-Ir-Nb] triple-triangular-lattice layers that can be tuned through synthesis conditions. Density functional theory calculations reveal that the coherent low-energy boundary interface plane of {101} between [11̅1] and [010] domains is responsible for the variable stacking behaviors. Energetically favorable structures are thereby reasonably proposed, based on nanoscale imperfect structure units. These findings provide valuable insights for designing and exploring new structures and functionalities within boride systems involving special geometry lattices.

This study aimed to analyze the effect of carbon fiber nanotube tracheotomy (CFNT) under swallowing training (ST) combined with bronchofiberoscope alveolar lavage (BAL), so as to provide theoretical guidance for the clinical treatment of pulmonary infection. 40 patients with pulmonary infection were selected as the research objects, and the effects of ST combined with BAL were analyzed after CFNT. The patients were randomly divided into four groups: a control group (group A) and three observation groups (groups B, C, and D), with 10 cases in each group. Patients in group A received conventional treatment, patients in group B received conventional treatment + ST, patients in group C received conventional treatment + BAL, and patients in group D received conventional treatment + ST + BAL. The effect of ST + BAL was analyzed after CFNT. The results showed that compared with the group A, the number of lung infections and infection rates in groups C and D was reduced (P < 0.05); the use time and per capita cost of antibiotics in group A were much higher than those in the groups C and D (P < 0.05); and in group B and D, the number of successful extubation of tracheal catheters and the success rate were greatly increased (P < 0.05) and the average time of intubation was dramatically shortened (P < 0.05). The scores of the water swallow test (WST) in groups B and D were much lower than the score of group A (P < 0.05), and the scores for swallowing ability and swallowing dysfunction scores were much different from those of the group A (P < 0.05). In summary, after a CFNT, the lung infection and swallowing function of patients were effectively improved after ST + BAL.