348 research outputs found
Development strategy of urban industrial diversification based on market potential and path dependence
Numerous studies conclude that urban industrial evolution depends on the technological relatedness-associated supply side. However, such industrial evolution may also be affected by market force-related demand side. To fill this gap, this research aims to examine whether market force, reflected by market potential and market segmentation, also has significant impacts on the diversification of regional industries, and whether such impacts differ among different regions of China. The data used export customs declaration data recorded by customs offices. We introduce the PROBIT binary variable model to explore the effects of technological relatedness, market motential, market segmentation on diversification of regional industry. The results show that the diversification of export industries was not only positively affected by technological relatedness, but also impacted by market potential and market segmentation positive and negative, respectively. Notably, the impact of technological relatedness on the innovation of export industry was weakened in areas with low market potential but strengthened in those with high market segmentation. Moreover, we found that the effect of technological relatedness was weakened in more developed cities, while the effects of market potential and market segmentation were relatively universal. Theoretically, this paper expands the framework of evolutionary economic geography. We understood the influential factors of industrial innovation from both the supply and demand side, instead of the solely supply side in most previous studies. Practically, this study points out a new development path for the industrial evolution of marginal areas
Screening and simulation of offshore CO2-EOR and storage:A case study for the HZ21-1 oilfield in the Pearl River Mouth Basin, Northern South China Sea
CO2-enhanced oil recovery (CO2-EOR) and storage is currently the most effective and economic technology for reducing CO2 emissions from burning fossil fuels in large scale. This paper is the first effort of proposing a modelling assessment of CO2-EOR and storage in the HZ2-1 oilfield in the Pearl River Mouth Basin in northern South China Sea offshore Guangdong Province. We attempt to couple the multi-parameter dimensionless quick screening model and reservoir compositional simulation for optimization of site screen and injection simulation. Through the quick screening, the reservoirs are ranked by FOR dimensionless recovery R-D, and by CO2 storage in pore volume SCO2. Our results indicate that SCO2 is highly pressure dependent and not directly related to R-D. Of these reservoirs, CO2-EOR and storage potential of the M10 was estimated through a compositional simulation as a case study based on a 3D geological model. Nine scenarios of CO2 injection operations have been simulated for 20 years with different well patterns and injection pressures. The simulation results represent an obvious improvement in oil production by CO2 flooding over No - CO2 production. The best operation for M10 is miscible CO2 flooding, which led to the higher recovery factors of 52%(similar to)58% and CO 2 stored masses of 8.1 x 10(6 similar to)10.8 x 10(6)t The optimum operation for CO2 injection should be set well pattern in region of injector I1 and high injection pressure for miscible flooding. In a whole, the HZ21-1 field can be used as a candidate geological site for GDCCUS project. We are fully aware of the limitation in the primary modelling including reservoir and fluid properties and production history matching, and regard this study as a general and hypothetic proposal
Hydrophilic PAN based carbon nanofibres with improved graphitic structure and enhanced mechanical performance using ethylenediamine functionalized graphene
Polyacrylonitrile (PAN) reinforced with nano-carbons such as graphene (Gr) and carbon nanotubes (CNTs) provides great opportunity for the development of low-cost and high-performance carbon materials. However, the poor dispersion and weak interaction between the carbon nanofillers and the surrounding PAN matrix prevent the final carbonized materials from reaching their full potential. Herein, we demonstrate a chemical approach using ethylenediamine (EDA) acting as a linker between graphene nanoplatelets and PAN for improved mechanical performance. The as-prepared CNFs exhibit a higher carbon yield and tensile modulus as well as improved graphitic structure compared to pristine PAN and PAN/Gr nanofibres. Furthermore, EDA can act as a N source for N-doping during the carbonization, enabling CNFs with hydrophilicity performance
La torre de doña Urraca en Covarrubias (Burgos)
La torre de doña Urraca en Covarrubias (Burgos
Single- and Multimagnon Dynamics in Antiferromagnetic -FeO Thin Films
Understanding the spin dynamics in antiferromagnetic (AFM) thin films is
fundamental for designing novel devices based on AFM magnon transport. Here, we
study the magnon dynamics in thin films of AFM -FeO by
combining resonant inelastic x-ray scattering, Anderson impurity model plus
dynamical mean-field theory, and Heisenberg spin model. Below 100 meV, we
observe the thickness-independent (down to 15 nm) acoustic single-magnon mode.
At higher energies (100-500 meV), an unexpected sequence of equally spaced,
optical modes is resolved and ascribed to , 2, 3, 4, and 5
magnetic excitations corresponding to multiple, noninteracting magnons. Our
study unveils the energy, character, and momentum-dependence of single and
multimagnons in -FeO thin films, with impact on AFM magnon
transport and its related phenomena. From a broader perspective, we generalize
the use of L-edge resonant inelastic x-ray scattering as a multispin-excitation
probe up to . Our analysis identifies the spin-orbital mixing
in the valence shell as the key element for accessing excitations beyond
, and up to, e.g., . At the same time, we
elucidate the novel origin of the spin excitations beyond the ,
emphasizing the key role played by the crystal lattice as a reservoir of
angular momentum that complements the quanta carried by the absorbed and
emitted photons.Comment: Accepted in Physical Review
A dynamic relationship between renewable energy consumption, non-renewable energy consumption, economic growth and CO2 emissions: Evidence from Asian emerging economies
This study aims to explore the relationship between renewable energy consumption, non-renewable energy consumption, carbon dioxide emissions and economic growth in China, India, Bangladesh, Japan, South Korea and Singapore using panel Augmented Mean Group (AMG) estimation techniques over the period 1975–2020. The results of the analysis show that renewable energy consumption, non-renewable energy consumption, employed labor force, and capital formation contribute significantly to long-run economic growth. The study also found that non-renewable energy consumption significantly increased long-term carbon emissions, while renewable energy consumption significantly reduced long-term carbon emissions. GDP and GDP3 have a significant positive impact on environmental degradation, while GDP2 has a significant negative impact on environmental degradation, thereby validating the N-type EKC hypothesis in selected emerging economies. The countrywise AMG strategy records no EKC in India and Bangladesh, an inverted U-shaped EKC in China and Singapore, and an N-shaped EKC in Japan and South Korea. Empirical evidence from the Dumitrescue-Hurlin (2012) panel causality test shows that there is a two-way causality between renewable energy consumption and economic growth, supporting the feedback hypothesis. Strategically, empirical evidence suggests that higher renewable energy is a viable strategy for addressing energy security and reducing carbon emissions to protect the environment and promote future economic growth in selected Asian countries
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