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Development zones constitute a special type of place‐based policy that has been implemented worldwide. As an essential economic development engine, Chinese National Economic and Technological Development Zones (NETDZs) are perceived as a successful example. However, few studies have looked into the channel effects at work in development zones concerning industrialization and urbanization, despite the crucial nature of such effects with regard to sustainable development of development zones. Following a brief description of NETDZs and their theoretical mechanisms with urban economic performance, industrialization, and urbanization, this study used a simultaneous equation model to generate empirical evidence of the impact of the establishment of NETDZs on urban economic performance and its channel effects through industrialization and urbanization. The results confirm that NETDZs exerts a positive and significant impact on urban economic performance, and NETDZs also show indirect influence in urban growth through urbanization. Although significant and positive intermediation of industrialization remains invalid, foreign direct investment and investment in fixed assets are still crucial in Chinese industrialization. Both industrialization and urbanization play an important role in Chinese urban economic development. Meanwhile, compared with eastern regions more influenced by urbanization, industrialization still acts as a major impetus in inland China. [ABSTRACT FROM AUTHOR]

To achieve carbon peak targets, realize carbon neutrality vision, and tackle global climate change, China must improve the carbon emission performance at the city level. Based on the carbon emission performance of 191 prefecture-level cities in China from 1997 to 2017, this paper analyses the evolution characteristics of urban carbon emission performance from three aspects: the overall spatial and temporal evolution, the differences according to both region and city size, and the differences among clusters categorized by carbon emission performance at the city level. This paper also reveals the impact of the social and economic transition on China's carbon emission performance. The results show that: (1) The overall level of carbon emission performance of Chinese cities is low, and there is a downward trend during the study period. The differences in carbon emission performance among cities are convergent, but there is a wide gap between high and low values. (2) The carbon emission performance of cities in eastern coastal areas is higher than that in non-coastal areas cities. Large urban agglomerations and economically developed regions, such as provincial capitals, are the agglomeration areas of high urban carbon emission performance values. (3) The carbon emission performance level of cities with similar sizes will converge. At the same time, such changes will enhance the differences among carbon emission performances at the city level within the same region. (4) Cities that belong to high urban carbon emission performance clusters are mainly distributed in the eastern region. Such cities are classified into large cities, supercities, and megacities. Compared with low urban carbon emission performance clusters, cities in high urban carbon emission performance clusters show a higher proportion in the medium-high level and high level of carbon emission performance. Moreover, cities in high urban carbon emission performance clusters are more likely to improve theirurban carbon emission performance. (5) The economic agglomeration effect, industrial structure adjustment and carbon intensity reduction have a significant impact on improving urban carbon emission performance. Population agglomeration has an incremental effect, and the anticipated benefits of environmental regulation have yet to be fully realized. The impacts of different clusters and different regions are variable. Finally, this paper advances policy enlightenment according to its research findings. [ABSTRACT FROM AUTHOR]

Restaurant recommendation is one of the most recommendation problems because the result of recommendation varies in different environments. Many methods have been proposed to recommend restaurants in a mobile environment by considering user preference, restaurant attributes, and location. However, there are few restaurant recommender systems according to the internet of vehicles environment. This paper presents a recommender system based on the prediction of traffic conditions in the internet of vehicles environment. This recommender system uses a phased selection method to recommend restaurants. The first stage is to screen restaurants that are on the user's driving route; the second stage is to recommend restaurants from the user attributes, restaurant attributes (with traffic conditions), and vehicle context, using a deep learning model. The experimental evaluation shows that the proposed recommender system is both efficient and effective. [ABSTRACT FROM AUTHOR]

[Display omitted] • STPP/CA can improve the parameter k of mixed-grained quartz. • STPP/CA can improve the selection function S 1 and the breakage function of single-grained quartz. • The surface properties and grindability of quartz are improved by STPP/CA. • The variation of kinetic parameters is consistent with the variation of quartz surface properties. The kinetic parameters of a grinding process can be used to study the variations in particle size reductions and grinding efficiencies. Appropriate grinding aids usually change the surfaces of a material and the properties of the pulp, thus improving the grinding efficiency. In this paper, pure quartz samples with mixed particle sizes and single particle sizes were selected as the raw materials. The effects of different sodium tripolyphosphate (STPP) and citric acid (CA) dosages on the dynamic parameters k , selection function S 1 and breakage function B for quartz grinding were studied. The results showed that the STPP and CA enhanced the grinding process of the quartz. In other words, the parameter k , the selection function S 1 and the breakage function B were all increased to varying degrees. The results of SEM, BET and contact angle measurements showed that the surfaces of the quartz particles became rounder, the specific surface area and average pore size increased, and the surface hydrophilicity increased. As a result, the grindability of the quartz increased, and the grinding kinetic parameters changed. Finally, the results showed that the improvements in the quartz grindability were consistent with the influence of grinding aids on the kinetic parameter k , selection function S 1 and breakage function B i,1. [ABSTRACT FROM AUTHOR]

Graph Neural Networks (GNNs) have received considerable attention in recent years due to their unique ability to model both topologies and semantics in the graphs. In this paper, we explore the use of GNNs in learning low-dimensional node representations in Heterogeneous Information Networks (HINs), which retain rich semantic information across multiple types of nodes and relations. Existing methods for HINs generally focus on modeling heterogeneity at either the node level or the relation level, but not both. As a result, these methods often fall short of optimal performance. To address this issue, we propose a novel Semantic- and Relation-aware Heterogeneous Graph neural Network, dubbed SR-HGN, which jointly incorporates rich semantics preserved on nodes and relations. Our approach involves projecting the HINs into a low-dimensional vector space through two steps: node-level aggregation and type-level aggregation. The node-level aggregation employs an attention mechanism to create relation vectors by aggregating messages from neighborhoods connected via the same type of relation. The type-level aggregation leverages relation vectors to aggregate node representations. In particular, we introduce semantic-aware attention and relation-aware attention in the type-level aggregation to model the contributions of relation vectors, in order to simultaneously gain knowledge from node semantics and relational information. Unlike other approaches that rely on pre-defined meta-paths, our model can be readily applied to most real-world applications without requiring any domain knowledge. To validate the effectiveness of our proposed approach, we conducted extensive experiments on three public datasets. Experimental results demonstrate that the SR-HGN significantly outperforms state-of-the-art baselines on node classification and node clustering tasks. [ABSTRACT FROM AUTHOR]

We investigated the factors influencing the progression of the pandemic from a global perspective by using the Geodetector and Correlation methods and explored the pandemic response policies and effects in different countries. The results yielded three notable findings. First, empirical results show the COVID-19 pandemic is influenced by various factors, including demographic and economic parameters, international travelers, urbanization ratio, urban population, etc. Among them, the correlation between urban population and confirmed cases is strongest. Cities become the key factor affecting the COVID-19 pandemic, with high urbanization levels and population mobility increases the risk of large-scale outbreaks. Second, among control measures, School-closures, International-travel-restrictions, and Public-gathering-restriction have the best control effect on the epidemic. In addition, the combination of different types of control measures is more effective in controlling the outbreak, especially for Public-gathering-restrictions ∩ School-closures, International-travel-restrictions ∩ Workplace-closures, Public-transport-restrictions ∩ International-travel-restrictions. Third, implementing appropriate control measures in the first month of an outbreak played a critical role in future pandemic trends. Since there are few local cases in this period and the control measures have an obvious effect. • Analysis the evolution and control of COVID-19 pandemic from global perspective. • The pandemic has been most severe in countries with high urbanization proportion, large urban populations. • The pandemic evolution is influenced by population, economic, urban, mobility characteristics and policy control factors. • School-closures, International-travel-restrictions, and Public-gathering-restriction have the best control effect. • The combination of different types of control measures is more effective in controlling the outbreak. • Corresponding control measures in the first month of the outbreak plays an important role in future trends of the pandemic. [ABSTRACT FROM AUTHOR]

In this paper, different dosages of TIPA, TEA and their combined grinding aid were added to the process of quartz grinding and their influence on the grinding efficiency and flotation recovery in DDA system was investigated. From the grinding and flotation experiments, It can be known that the effect of the combined grinding aid was better than that of a single reagent, which can not only significantly improve the grinding efficiency of quartz, but also increase the recovery of quartz from flotation. Based on the results of FT-IR spectroscopy, XPS analysis, quantum chemistry and solution chemistry calculations, it can be seen that the hydroxyl groups in the TIPA/TEA combined grinding aid formed hydrogen bonds with O on the (101) surface of quartz, while collector DDA was mainly electrostatically adsorbed on the surface of quartz with negative potential, and the introduction of combined grinding aid improved the adsorption of DDA, the grinding aid and collector played a synergistic role instead of competitive adsorption. The detection of contact angle and surface tension showed that the combined grinding aid can improve the hydrophobicity of quartz, reduce the surface tension and CMC value of DDA, and enhance the dispersibility of quartz, therefore, it can increase the recovery of quartz from flotation. [Display omitted] • TIPA/TEA can significantly improve grinding efficiency of quartz. • TIPA/TEA combined grinding aid can increase the recovery of quartz in DDA system. • Grinding aid and collector played a synergistic role instead of competitive adsorption. • TIPA/TEA can promote the adsorption of DDA. [ABSTRACT FROM AUTHOR]

With the widespread concern of oily wastewater discharge and environmental protection, the efficient electrospun nanofiber membrane has fascinated strenuous attention owes to its uniform pore distribution and adjustable wettability. However, the common modification methods of nanofiber membranes, such as surface coating and grafting, have complicated procedures and low grafting rate, which limits their wide application in practical applications. Hence, a polyvinylidene fluoride (PVDF), polyvinylpyrrolidone (PVP) and inorganic titanium dioxide (TiO 2) nanoparticles blend nanofiber membrane was prepared by convenient one-step electrostatic spinning. The existence of PVDF provides certain strength and chemical resistance property, and the PVP benefits the loading of TiO 2 NPs and improves the hydrophilicity as well as mechanical strength of the membrane. The introduction of these three components makes the porous nanofiber membrane have a hierarchical rough structure, and appear hydrophilic in the air and oleophobic under water. The obtained membrane thus shows excellent separation efficiency (98.4%) for different emulsions, desirable antifouling property with a high flux recovery rate (FRR 95.68%) and a low total fouling ratio (15.18%) after several cycles. This strategy will be a facile and promising method of preparing reusable and functional separation membranes. [Display omitted] • The PVDF membrane was prepared by one-step electrostatic spinning. • The membrane was modified by adding water-soluble polymer PVP and TiO 2. • The membrane showed durable anti-fouling and oil-water separation properties. [ABSTRACT FROM AUTHOR]

The self-wrinkling coating with surface microphase morphology and hierarchical cross-linked structure for impact resistance and mechanical enhancement. [Display omitted] Protective materials are essential for personal, electronic, and military defenses owing to their efficient impact-resistant and energy-absorbing properties. Inspired by the bottom-up fabrication process and energy dissipation mechanism of natural organisms with hierarchical structures, we demonstrated a self-wrinkled photo-curing coating as a new protective material for enhancing the anti-impact property of the substrates. Owing to the self-assembly of polydimethylsiloxane (PDMS) containing polymeric photoinitiator on the surface, the liquid coating formulation was photo-cured by one-step UV irradiation with simultaneous generation of self-wrinkled surface morphology and a gradient cross-linked architecture. The maximum impact resistance height (h max) of the glass substrate coated with plain coating increased from 120 to 180 cm when coated with wrinkled gradient coating. Furthermore, the Young's modulus, fracture stress, and toughness of the wrinkled gradient coating film improved from 39.6 MPa, 2.4 MPa, and 74.1 MJ/cm3 to 235.0 MPa (∼5× increase), 18.5 MPa (∼6.6× increase), and 845.0 MJ/cm3 (∼10.8× increase) compared to the pure coating film as reference. The theoretical simulation and experimental results proved that the surface self-wrinkled morphology and intrinsic hierarchical architecture contribute to the energy dissipation and impact resistance of the cured coating. The photo-curing process, a bottom-up strategy, is conducted in a non-contact mode compared with nano-printing and lithography, enabling bulk materials to be engineered. [ABSTRACT FROM AUTHOR]

• Studies partial discharge induced thermal decomposition of composite insulator epoxy. • Analyzes 200–1000 °C pyrolysis products of anhydride-cured bisphenol A epoxy resin. • Crosslinking points cleave below 360 °C; epoxy main chains break above 380 °C. • Formed gases, swelling-induced liquids and acids can impact insulator components. • Proposes product formation mechanisms and mitigating strategies to their effects. Epoxy/anhydride thermoset matrix within composite insulator core rods may thermally decompose by temperature rise caused by partial discharge. The thermal decomposition characteristics of the epoxy/anhydride thermoset was analyzed using pyrolysis-gas chromatography-mass spectrometry (PY–GC–MS) from 200 to 1000 °C, including the mechanisms of crosslinked network scission and the formation of gaseous or liquid products with potential secondary effects on surrounding materials. Below 360 °C, scission at crosslinking points predominates by ceiling temperature behavior, forming anhydrides. Above 380 °C, scission of main chains leads to the production of corresponding fragments. Beyond 600 °C, decomposition of anhydrides and fragments from main chains leads to the formation of lower molecular weight substances. During the pyrolysis process, organic acids are formed from 240 °C to 1000 °C. Above 600 °C, gases with high vapor pressures and liquids that can induce swelling are produced. These byproducts can have secondary effects on surrounding materials, including the failure of interfacial adhesion, swelling of silicone rubber sheaths, and a reduction in the mechanical strength of glass fibers. Consequently, these effects may accelerate the decay-like deterioration of core rods, characterized by a surface morphology reminiscent of rotting wood. These findings will inform the optimization of materials for enhanced electrical equipment performance and facilitate the evaluation of potential environmental impacts posed by the thermal decomposition of epoxy/anhydride thermosets in future applications. [ABSTRACT FROM AUTHOR]

The grinding process urgently needs to address the technical challenges of high energy consumption and low efficiency. In this paper, in order to improve the efficiency of magnesite grinding process, sodium tripolyphosphate (STPP) was selected as a grinding aid. Grinding tests showed that STPP significantly improved the mass fraction of − 0.074 mm in grinding products by 6.8% points. The mechanism of STPP on grinding process was analyzed by Fourier transform infrared spectrum (FT-IR) measurement, contact angle detection, zeta potential test, specific surface area and scanning electron microscopy (SEM) tests. The FT-IR and contact angle measurement results indicated that STPP had chemical and physical adsorption on magnesite surface, which improved its hydrophilicity, and promote water wetting action furtherly. So it can improve the grindability of magnesite. It can be seen by zeta potential detection that STPP increased the absolute value of magnesite to increase the electrostatic repulsion energy between particles (U E). And then, the dispersion of particles was improved. In addition, specific surface area and SEM tests indicated that STPP can increase the specific surface area of grinding products, and extend the defects and cracks of magnesite surface. [Display omitted] • Sodium tripolyphosphate can improve the grinding efficiency of magnesite. • Sodium tripolyphosphate had chemical and physical adsorption on the surface of magnesite. • Sodium tripolyphosphate improved the grindability and dispersion of magnesite in the grinding process. [ABSTRACT FROM AUTHOR]