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Globalization and informatization have exerted far-reaching impacts on the spatial connection and development of urban systems. This study, concerning the network of an urban system based on the space of flows, supplements the insufficiency on the micro-level in macro-urban network research. Taking Nanjing as an example, this study explores the characteristics of the network of the urban system from the perspective of people flow, refining the granularity of the analysis to the township- and street-level spatial units using mobile phone data. The findings are as follows: (1) There is a multicenter layered network pattern, with the main urban area being the core of the network, while Dongshan Street and Moling Street, as secondary centers, form a joint development pattern with the main urban area. (2) The spatial differentiation is significant. The spatial heterogeneity of "centralization in the central region, delayering in the north, and hierarchization in the south" is obvious. The net people inflow nodes are mainly concentrated in the main urban area and its surroundings, while the net outflow nodes are mostly located on the edge of the city. Moreover, the nodes to the south of Yangtze River are advantageous in urban resource control. (3) The phenomenon of "double shadow circle" appears in the ring of the main city and the ring of the municipal area. Moreover, the northern district experiences a serious outflow of population. (4) The effect of policy intervention is beginning to show. Improved levels of development of street and township units such as Jiangbei New District show the positive influence of national strategy on regional development. [ABSTRACT FROM AUTHOR]

In the knowledge economy era, innovation has become a key emphasis for urban competitions. This paper constructs a theoretical research framework that integrates the basic understandings, influencing factors and ensuing results of intercity innovative competition relations. On the basis of data from the general programs of the National Natural Science Foundation of China from 2005 to 2019, this paper constructs intercity innovative competition relations in China, analyses their spatial distribution and quantitative characteristics, and quantitatively investigates the impact of urban innovation capacity and multidimensional proximity (e.g., geographical proximity, institutional proximity and cognitive proximity) on intercity innovative competition relations through a negative binomial model. The study obtained the following findings: (1) In terms of the overall intercity innovative competition relations, the intensity of China's intercity innovative competition relations gradually increased from 2005 to 2019, with a spatial clustering towards cities with high administrative ranks (e.g., municipalities directly under the central government, sub-provincial cities and provincial capitals); Beijing is always at the centre of innovative competition relations, but its standing has slightly slipped in recent years. (2) From the perspective of disciplines, cities can become benchmarks in particular fields of innovative competitions by competing according to their disciplinary strengths; intercity innovative competition relations in China vary across various academic disciplines. (3) In terms of influencing factors, urban innovation capacity has significant positive effects on intercity innovative competition relations; geographical proximity, institutional proximity and cognitive proximity all have significant positive effects on innovative competition relations; and interactions occur between multidimensional proximities, including a complementary effect between geographical proximity and institutional proximity, a substitutive effect between cognitive proximity and geographical proximity, and a substitutive effect between cognitive proximity and institutional proximity. [ABSTRACT FROM AUTHOR]

Despite the increasing attention given to smart tourism in China, limited research has been conducted on this topic. The purpose of this research was to analyze the stakeholders, applications, experiences, and challenges of smart tourism in China. Public–private partnership played a dominant role in China's smart tourism construction. Smart technologies were applied in information platform construction, tourism statistics innovation, information offering, overcrowding management, environment and resource protection, experience co-creation and personalization, tourism traffic, and marketing. The experiences and challenges of China's smart tourism initiative, which can provide valuable implications for other destinations to improve smartness level, were also identified. [ABSTRACT FROM AUTHOR]

The electrical response of boron nitride nanocones (BNNCs) to 5-Fluorouracil (5FU) drug was investigated by first-principle density functional theory (DFT). The adsorption of 5FU causes a significant decrease in the BNNCs HOMO-LUMO gap (from 4.60 to 3.39 eV), thereby, the electrical conductivity has also increased. It indicates that the BNNCs could be an appropriate candidate for 5FU detection and may be used in the electronic sensors. Furthermore, the work function of BNNCs is influenced by the 5FU adsorption and the work function of BNNCs is reduce about 18.99%, it could also be a work function based sensor for the detection of 5FU. The BNNCs have also the advantage of short recovery time about 4.25 ms for desorption of 5FU. [ABSTRACT FROM AUTHOR]

The almost monodisperse three dimensional (3D) porous CeO2 hollow nanospheres with a diameter of about 200–500 nm and rough surface have been synthesized by a facile template-free hydrothermal route. It was found that each hollow spherical nanostructure is composed of numerous nubbly nano-particles with several decade nanometers in diameter as the building blocks, which are randomly assembled with lower density to form a 3D porous structure. Many characterization means have been employed to study the CeO2 hollow nanospheres, including X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, Raman, and ultraviolet–visible spectrum. The 3D CeO2 hollow nanospheres own a cubic fluorite structure and many Ce3+ ions and oxygen vacancies exist in their surface. The morphology structure of samples, size of building blocks, and the oxygen vacancies may be the reason for the red-shifted in band gap of the 3D CeO2 hollow nanospheres. [ABSTRACT FROM AUTHOR]

The large-scale beautiful shuttle-like nanostructures with numerous nanorods assembling at both ends have been purposefully fabricated via a facile and efficient hydrothermal route. Various techniques have been applied to investigate the CeO nanostructures, including XRD, SEM, XPS, Raman spectra, PL spectra. The XRD results demonstrate that all the samples own a cubic fluorite structure of CeO with no other crystalline impurity phase. The results show that the morphology of the as-synthesized nanostructures gradually changes from rough shuttle-like structure to smooth shuttle-like structure with the increase of the amount of NHHCO. It is found that there are many Ce ions and oxygen vacancies in surface of samples, which can account for their similar room temperature photoluminescence emission peaks. Their PL intensity is different from each other, which may be attributed to the effect of different morphology and size of the samples. [ABSTRACT FROM AUTHOR]