In the context of rural revitalization strategy, sports and culture industry, with its wide coverage and strong inclusiveness, has become an important grip to boost rural revitalization. The ...development of sports tourism industry needs to rely on innovation drive. China’s sports tourism industry has stepped into the stage of high-quality development from traditional rough development. Under the strategy of rural revitalization, the issue of the significant impact of innovation on sports tourism development is addressed. This paper uses case studies and other methods to analyze the policy background of rural revitalization and sports industry development in conjunction with the promotion and application of big data today, and elaborates the value implication and role mechanism of sports industry to promote rural revitalization. At the same time, it explores the mechanism of the integration development of rural sports culture and sports tourism from four different perspectives: factor-driven, goal-oriented, resource-oriented and sports segment-guided. Finally, the “technology-fund-talent-synergy” innovation mechanism is constructed, and through the analysis of the difficulties faced by the development path of integration of rural sports culture and sports tourism, several suggestions are put forward to realize the development path of integration of rural sports and tourism. It proposes a driving path of technological innovation, capital innovation, talent innovation and collaborative innovation, and provides theoretical support for the high-quality development of sports tourism industry.
This study investigates the effects of steel fiber and silica fume on the mechanical and fracture properties of ultra-high performance geopolymer concrete (UHPGC). Four volume fractions of steel ...fiber (0%, 1%, 2% and 3%) and four contents of silica fume by the mass of total binders (5%, 10%, 20% and 30%) were used. The mechanical and fracture properties evaluated include the compressive, splitting tensile and ultimate flexural strengths, modulus of elasticity, flexural behavior, fracture energy and stress intensity factor. In addition, the correlations among the compressive and splitting tensile strengths, and compressive strength and elastic modulus were studied. The results indicated the increase of steel fiber dosage resulted in the decrease of the workability, but the continuous improvement of mechanical and fracture performance of UHPGC. The empirical equations for predicting elastic modulus of conventional ultra-high performance concrete overestimated the elastic modulus of UHPGC, however some prediction formulas for the splitting tensile strength of PC-based concretes could be applied for UHPGC. Silica fume had a complicated influence on workability and hardened properties of UHPGC, which is strongly dependent on its amount. The inclusion of 10% silica fume induced the increase of the flowability, but the sharp degradation of the mechanical performance, while the specimens with 20% and 30% silica fume possessed the superior mechanical characteristic to that with 5% silica fume. The steel fiber dosage could be decreased without sacrificing the mechanical and fracture performance of UHPGC, via the increase of silica fume content.
This study reports the development of ultra-high performance geopolymer concrete (UHPGC) and overcoming the brittleness feature of geopolymer matrix by using different steel fibers. Four straight ...steel fibers with different aspect ratios and two different deformed steel fibers were investigated. Flowability, compressive strength and flexural behavior including strengths and deflection, and energy absorption capacity of UHPGC, were systematically evaluated. A deformation ratio of steel fiber was introduced to quantitatively correlate the steel fiber shape and the mechanical performance. The flowability of fresh UHPGC mixtures decreased when the fiber content and length increased, as expected, and was inconspicuously influenced by fiber shape. The increase in fiber content and the decrease of fiber diameter contributed to the improvement of the mechanical strengths of UHPGC. The flexural behaviors of UHPGC improved as the fiber volume and length increased, while the compressive and first crack strengths were affected by both curing conditions and fiber dosages as well. Different from Portland cement-based composites, the corrugated fibers with a higher deformation ratio added in UHPGC, had an inferior strengthening and toughening efficiency, while for straight fibers, those longer and smaller in diameter were more preferred. Finally, based on the previous research, a new one with adjustment and simplification was proposed for that of newly-developed UHPGC, and the fitted results had higher correlation coefficients (r2).
The mechanical properties of the constituent minerals in shale rock are fundamental to a better knowledge of multi-scale shale behaviors. It benefits the engineering applications and predictive ...physics modeling of the shale formation. In this work, nanoindentation testing combined with scanning electron microscopy - energy dispersive spectroscopy (SEM-EDS) were used to obtain the in situ mechanical properties of individual mineral phases in four shale samples. Engraved cross-marks were employed to locate the indented areas on a micron scale for subsequent SEM-EDS measurements and analysis. The elastic moduli and hardness of the quartz, iron-type minerals, muscovite, clinochlore, organic matter, and the mineral assortments in the matrix were analyzed and relevant deformative behaviors were compared. Results show that the identified mineral groups exhibit a diverse set of mechanical properties at the nanoscale. The iron-type minerals have the highest elastic modulus (104.7 GPa), then followed by quartz, muscovite, clinochlore, and organic matter. Quartz shows the highest hardness (10.2 GPa). The identified minerals demonstrated different elasto-plastic characteristics to the indentation loads. Quartz exhibits the lowest plastic behavior, while phyllosilicates exhibited large plastic behavior owing to the layered structure. Organic matter showed both elastic-dominant and plastic-dominant behaviors, which may be related to the chemical compositional differences and various thermal maturity of kerogen in the shale samples. The mechanical properties of three mineral assortments in shale matrices vary significantly due to the wide variety of the mineral compositions. Radial cracks were observed on the boundary of brittle minerals and relatively weak minerals, while shear cracks were observed on strength-weak minerals such as layered silicates and organic matters. The mechanism of the induced cracks was discussed. This study obtains a basic understanding of shale behavior on nano-scale and provides reliable basic data for multi-scale modeling of shale reservoirs without the need for large-scale mechanical tests.
It is highly desired but still remains challenging to design and develop a Co‐based nanoparticle‐encapsulated conductive nanoarray at room temperature for high‐performance water oxidation ...electrocatalysis. Here, it is reported that room‐temperature anodization of a Co(TCNQ)2 (TCNQ = tetracyanoquinodimethane) nanowire array on copper foam at alkaline pH leads to in situ electrochemcial oxidation of TCNQ− into water‐insoluable TCNQ nanoarray embedding Co(OH)2 nanoparticles. Such Co(OH)2‐TCNQ/CF shows superior catalytic activity for water oxidation and demands only a low overpotential of 276 mV to drive a geometrical current density of 25 mA cm−2 in 1.0 m KOH. Notably, it also demonstrates strong long‐term electrochemical durability with its activity being retrained for at least 25 h, a high turnover frequency of 0.97 s−1 at an overpotential of 450 mV and 100% Faradic efficiency. This study provides an exciting new method for the rational design and development of a conductive TCNQ‐based nanoarray as an interesting 3D material for advanced electrochemical applications.
A Co(OH)2 nanoparticle‐encapsulating conductive tetracyanoquinodimethane (TCNQ) nanowire array on copper foam is prepared using an in situ electrochemical oxidation method to form a water‐insoluable conductive TCNQ nanoarray. This array effectively entraps Co(OH)2 nanoparticles at alkaline pH. Such Co(OH)2‐TCNQ/CF requires an overpotential as low as 276 mV to drive a geometrical current density of 25 mA cm−2 in 1.0 M KOH, with strong long‐term electrochemical durability.
The variations of mechanical properties of coals in nano-to-micro scale play vital roles in defining the coal deformative and failure behaviors with a wide range of engineering applications, ...including coal stimulation for gas recovery and/or CO2 sequestration in coal seams. Based on the assumption that the heterogeneity in the mechanical properties of coals is combinedly determined by the mineralogical/carbon compositions and microstructures, three coals were experimentally measured through combing nanoindentation test, X-ray diffraction (XRD) analysis and field emission scanning electron microscopy - energy dispersive spectroscopy (FESEM-EDS) imaging. Two sub-bituminous coals from Illinois basin and one bituminous coal from Pittsburgh No.8 seam from Pennsylvania were collected and prepared. The moduli, hardness, and energy dissipations were all analyzed for three coals. The mean Young's moduli and hardness of two sub-bituminous and bituminous coals are ~4.13 GPa, ~4.79 GPa, and ~ 5.56 GPa respectively and the mean hardness of which are ~0.38 GPa, ~0.49 GPa and ~ 0.58 GPa respectively. The results confirmed that the nanoscale mechanical properties are compositional and microstructural dependent. It was also observed that the heterogeneity of sub-bituminous coals is more apparent than the bituminous coal. Also, the bituminous coal is more harder and brittle than sub-bituminous coal, which can better withhold the mechanical response, but the deformations are relatively permanent due to brittle failure. The energy dissipation data showed that the irreversible work decreases with the increase in hardness, which confirmed that the plastic deformation is much more easily to be inducted. The mechanism-based phenomenon pop-in event on the load-displacement curve was also analyzed by linking with the characteristics of the morphology and composition beneath a pointed indenter or cracks formation due to the localized indent.
Abstract
Effecting the synergistic function of single metal atom sites and their supports is of great importance to achieve high-performance catalysts. Herein, we successfully fabricate ...polyoxometalates (POMs)-stabilized atomically dispersed platinum sites by employing three-dimensional metal-organic frameworks (MOFs) as the finite spatial skeleton to govern the accessible quantity, spatial dispersion, and mobility of metal precursors around each POM unit. The isolated single platinum atoms (Pt
1
) are steadily anchored in the square-planar sites on the surface of monodispersed Keggin-type phosphomolybdic acid (PMo) in the cavities of various MOFs, including MIL-101, HKUST-1, and ZIF-67. In contrast, either the absence of POMs or MOFs yielded only platinum nanoparticles. Pt
1
-PMo@MIL-101 are seven times more active than the corresponding nanoparticles in the diboration of phenylacetylene, which can be attributed to the synergistic effect of the preconcentration of organic reaction substrates by porous MOFs skeleton and the decreased desorption energy of products on isolated Pt atom sites.
The pursuit of equity is one of the basic principles behind the strengthening of health care reform. China's new rural cooperative medical insurance (NRCMI) and urban residents' basic medical ...insurance (URBMI) are both "equalized" in terms of fundraising and reimbursement. This paper studies the benefits equity under this "equalized" system.
The data analysed in this paper are from the China Family Panel Studies (CFPS) from 2014 to 2016, implemented by the Institute of Social Science Survey at Peking University. A two-part model and a binary choice model are used in the empirical test.
The empirical test revealed that high-income people benefit more from basic medical insurance than low-income people. Mechanism analysis demonstrated that high-income people have higher medical insurance applicability and can utilize better health care. Since low-income people are unhealthier, inequity in benefits exacerbates health inequity. We also found that the benefits equity of URBMI is better than that of NRCMI.
The government needs to pay more attention to the issue of medical insurance inequity. We should consider allowing different income groups to pay different premiums according to their medical expenses or applying different reimbursement policies for different income groups.
Vascular dementia (VD) is a common neurodegenerative disease, and the cognitive dysfunction is a major manifestation of VD. Lots of evidences showed that beta-amyloid (Aβ) deposition and ...neuroinflammation act as vital elements in the progress of VD. The previous studies showed that osthole (OST) can improve the cognitive function of VD and Alzheimer’s disease (AD). However, the effect of OST on Aβ in VD brain is still unclear. Chronic cerebral hypoperfusion (CCH) of rats were used to investigate the effect of OST on Aβ through nod-like receptor protein 3 (NLRP3) inflammasome in this study. Morris Water Maze and Y-maze were used to test the spatial learning, memory and working abilities. Hematoxylin–eosin (H&E) and Nissl staining were used to observe the morphology and number of hippocampal neurons. Immunofluorescence staining was used to observe the number of microglia activated. Western blot was used to detect the expression of proteins. The study results showed that OST obviously enhanced the spatial learning, memory and working abilities induced by modified bilateral common carotid artery occlusion (BCCAO) in rats, improved the pathological damage of hippocampal neurons induced by BCCAO in rats, inhibited the activation of microglia induced by BCCAO in rats. Furthermore, this study also discovered that OST reduced Aβ deposition in VD hippocampus via inhibition the NLRP3 inflammasome. Together, these results suggest that OST reduces Aβ deposition via inhibition NLRP3 inflammasome in microglial in VD.
Systemic chronic hypoxia is a feature of many diseases and may influence the communication between bone marrow (BM) and gut microbiota. Here we analyse patients with cyanotic congenital heart disease ...(CCHD) who are experiencing chronic hypoxia and characterize the association between bone marrow mesenchymal stem cells (BMSCs) and gut microbiome under systemic hypoxia. We observe premature senescence of BMSCs and abnormal D-galactose accumulation in patients with CCHD. The hypoxia that these patients experience results in an altered diversity of gut microbial communities, with a remarkable decrease in the number of Lactobacilli and a noticeable reduction in the amount of enzyme-degraded D-galactose. Replenishing chronic hypoxic rats with Lactobacillus reduced the accumulation of D-galactose and restored the deficient BMSCs. Together, our findings show that chronic hypoxia predisposes BMSCs to premature senescence, which may be due to gut dysbiosis and thus induced D-galactose accumulation.
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