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1.
Heliyon ; 10(12): e33188, 2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39005913

RESUMO

Promoting the green development of agriculture is of great significance to realize agricultural and rural modernization in China. Based on the existing research, this paper innovatively explores the dynamic and spatial effects of agricultural green development in the eight newly zoned regions of China's economy. Based on the panel data of 30 provinces in China from 2013 to 2022, this paper selects 20 indicators to measure the level of agricultural green development from five dimensions such as ecological protection, resource conservation, environment-friendly, green supply and economic growth by entropy weight method and uses non-parametric estimation method to analyze the dynamic evolution trend of agricultural green development in the whole country and its eight economic regions. Then, a spatial econometric model is constructed to further explore the influence mechanism and spatial spillover effect of each influencing factor on agricultural green development. The findings demonstrate that the level of agricultural green development in 30 provinces of China continuously improved during the study period, but the dynamic evolution trend characteristics in the whole country and its eight economic regions are not the same. Specifically, the development differences between the whole country, the northeast region, the eastern coast, the southern coast and the northwest region increased, while that between the northern coast, the Yellow River basin and the middle reaches of the Yangtze River first increased and then decreased, and that in the southwestern region gradually narrowed. There is a significant spatial spillover effect on agricultural green development and its influencing factors. Moreover, there is heterogeneity in the influence characteristics and spatial spillover effects of various influencing factors on agricultural green development among the eight economic regions. Therefore, it is proposed that eight economic regions in China should formulate differentiated development strategies, focus on educational and technological innovation etc., and further promote agricultural green development.

2.
J Med Virol ; 96(7): e29800, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39014958

RESUMO

Globally, the rollout of COVID-19 vaccine had been faced with a significant barrier in the form of vaccine hesitancy. This study adopts a multi-stage perspective to explore the prevalence and determinants of COVID-19 vaccine hesitancy, focusing on their dynamic evolutionary features. Guided by the integrated framework of the 3Cs model (complacency, confidence, and convenience) and the EAH model (environmental, agent, and host), this study conducted three repeated national cross-sectional surveys. These surveys carried out from July 2021 to February 2023 across mainland China, targeted individuals aged 18 and older. They were strategically timed to coincide with three critical vaccination phases: universal coverage (stage 1), partial coverage (stage 2), and key population coverage (stage 3). From 2021 to 2023, the surveys examined sample sizes of 29 925, 6659, and 5407, respectively. The COVID-19 vaccine hesitation rates increased from 8.39% in 2021 to 29.72% in 2023. Urban residency, chronic condition, and low trust in vaccine developer contributed to significant COVID-19 vaccine hesitancy across the pandemic. Negative correlations between the intensity of vaccination policies and vaccine hesitancy, and positive correlations between vaccine hesitancy and long COVID, were confirmed. This study provides insights for designing future effective vaccination programs for emerging vaccine-preventable infectious X diseases.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Hesitação Vacinal , Humanos , Estudos Transversais , Vacinas contra COVID-19/administração & dosagem , COVID-19/prevenção & controle , COVID-19/epidemiologia , China/epidemiologia , Pessoa de Meia-Idade , Adulto , Masculino , Feminino , Hesitação Vacinal/estatística & dados numéricos , Hesitação Vacinal/psicologia , Idoso , Adulto Jovem , Adolescente , SARS-CoV-2/imunologia , Vacinação/psicologia , Vacinação/estatística & dados numéricos , Inquéritos e Questionários , População do Leste Asiático
3.
Sci Rep ; 14(1): 16367, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014132

RESUMO

As China strives to balance rapid urbanization with environmental conservation, increasing attention is being paid to the pursuit of green production efficiency (GPE) in the real estate industry. The undesirable super-SBM model was used to calculate the GPE of China's real estate industry from 2001 to 2020. Additionally, GPE spatial distribution characteristics in China's real estate industry were analyzed using the standard deviation ellipse (SDE), Moran's index, Theil index, random kernel density estimation (RKDA), and spatial Markov chain (SMC) methods. The GPE exhibited a U-shaped trend, with 2008 as the inflection point, first decreasing and then increasing. It reached a maximum value of 0.747 in 2020. The Theil index increased from 0.043 to 0.121 nationwide, indicating the overall characteristics of low-level slow growth, and imbalance. Discrepancies in input-output scales, the southward shift of economic centers, and population movements contribute significantly to the disparities between the east and west, north and south, and regions divided by the Hu Huanyong Line (Hu Line). The GPE exhibited club convergence characteristics; however, polarization phenomena exist in local areas. Spatial spillover effects were also observed in GPE. Finally, we provide recommendations for promoting green development in the real estate industry, including green building technology, fiscal subsidy investment, and population migration management.

4.
Heliyon ; 10(8): e29880, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38699725

RESUMO

It is crucial to scientifically assess China's rural revitalization and grasp its evolution laws. This paper constructs an indicator system to measure the level of rural revitalization in China from 2011 to 2021 using the entropy weight method. Then, we explore the spatial and temporal divergence and dynamic evolutionary characteristics of rural revitalization using the Dagum Gini coefficient and Kernel density. We found that the level of rural revitalization in China is low but fluctuating and increasing. Regionally, eastern China scores higher than central, western and northeastern China. In terms of dimensions, ecological livability scores are higher than prosperous industry, effective governance, affluent living and civilized countryside in that order. The regional differences in the level of rural revitalization are mainly reflected between regions, especially between eastern and western China, but the gap between regions is narrowing year by year. And the results of the Kernel density show that the level of rural revitalization in China shows a slow and balanced growth, but the eastern China shows a polarization growth. These findings can provide a comprehensive and objective outline of the advantages and shortcomings of rural revitalization development in China, and provide a policy reference for the comprehensive and stable promotion of rural revitalization construction.

5.
Sci Rep ; 14(1): 11322, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760393

RESUMO

Based on the theory of empty hole effect of cutting blasting, the Hopkinson effect and Saint-Venant principle are integrated to establish a two-dimensional calculation model of dynamic stress evolution of the holes wall, and then the dynamic fracture mechanism and damage distribution mode of the rock mass in the cutting area under the action of longitudinal waves are predicted. The results of the calculation and numerical simulation are verified by experiments, and the results show that: The time-varying stress function of the circular cavity wall conforms to the periodic dynamic evolution of the trigonometric function, and the theoretical calculation is consistent with the simulation results. Through the calculation of the round holes cut model and the square empty hole cut model, the change of the shape of the holes in the cut area changes the failure form of the surrounding rock mass. The circular empty hole wall is affected by the stress wave to produce "interval ring" destruction, and the effect of the reflected stretch wave is inhibited. The large range of rock mass in the square empty hole wall produces tensile and shear failure, and the rock mass collapses inward under the influence of the second stage stress. Among them, the empty space utilization rate of the square empty hole model is about 8.5 times that of the circular holes model. Vibration monitoring in the center of the cutting area shows that the vibration effect of the circular empty hole is larger than that of the square empty hole, and the proportion of rock breaking energy is lower.

6.
Adv Mater ; 36(26): e2401110, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38549546

RESUMO

Manipulating the structural and kinetic dissociation processes of water at the catalyst-electrolyte interface is vital for alkaline hydrogen evolution reactions (HER) at industrial current density. This is seldom actualized due to the intricacies of the electrochemical reaction interface. Herein, this work introduces a rapid, nonequilibrium cooling technique for synthesizing ternary Turing catalysts with short-range ordered structures (denoted as FeNiRu/C). These advanced structures empower the FeNiRu/C to exhibit excellent HER performance in 1 m KOH with an ultralow overpotential of 6.5 and 166.2 mV at 10 and 1000 mA cm-2, respectively, and a specific activity 7.3 times higher than that of Pt/C. Comprehensive mechanistic analyses reveal that abundant atomic species form asymmetric atomic electric fields on the catalyst surface inducing a directed evolution and the dissociation process of interfacial H2O molecules. In addition, the locally topologized structure effectively mitigates the high hydrogen coverage of the active site induced by the high current density. The establishment of the relationship between free water population and HER activity provides a new paradigm for the design of industrially relevant high performance alkaline HER catalysts.

7.
Sci Total Environ ; 926: 171901, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38521270

RESUMO

Drought displays dynamic and uncertain spatiotemporal characteristics, thus it is typically not confined to fixed temporal-spatial boundaries. Existing drought clustering methods often involve spatially clustering drought points or grids into patches, subsequently connected over time to form three-dimensional structures. Despite this process being able to extract three-dimensional drought clusters, it is likely to overlook mild or relatively small, isolated drought patches. To overcome this limitation, this paper presented an effective method (named STD-CLUSTER) for identifying drought clusters with complete three-dimensional structures. The method initially employed run theory to extract drought events as "lines" and subsequently clustered these events using the Density-Based Spatial Clustering of Applications with Noise (DBSCAN) algorithm. A case study on the 2006 flash drought in the Yangtze River Basin demonstrated that STD-CLUSTER successfully clustered drought events and ensured the integrity of drought clusters by considering small, isolated, or disconnected patches. Additionally, an in-depth analysis using STD-CLUSTER examined seasonal drought events in China from 1991 to 2022, identifying a total of 35 drought clusters. These clusters began and ended with small-area patches, exhibiting features of expansion, contraction, spread, merging, and splitting over time. Furthermore, seasonal changes significantly influenced the evolution of drought clusters, with affected area and severity increasing in spring and summer and decreasing in autumn and winter. The applicability of the proposed method extends beyond various geographical regions and time scales, providing effective support for comprehensively investigating the spatiotemporal evolution of drought.

8.
Natl Sci Rev ; 11(4): nwae042, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38487497

RESUMO

Tracking the dynamic surface evolution of metal halide perovskite is crucial for understanding the corresponding fundamental principles of photoelectric properties and intrinsic instability. However, due to the volatility elements and soft lattice nature of perovskites, several important dynamic behaviors remain unclear. Here, an ultra-high vacuum (UHV) interconnection system integrated by surface-sensitive probing techniques has been developed to investigate the freshly cleaved surface of CH3NH3PbBr3  in situ under given energy stimulation. On this basis, the detailed three-step chemical decomposition pathway of perovskites has been clarified. Meanwhile, the evolution of crystal structure from cubic phase to tetragonal phase on the perovskite surface has been revealed under energy stimulation. Accompanied by chemical composition and crystal structure evolution, electronic structure changes including energy level position, hole effective mass, and Rashba splitting have also been accurately determined. These findings provide a clear perspective on the physical origin of optoelectronic properties and the decomposition mechanism of perovskites.

9.
Environ Sci Pollut Res Int ; 31(11): 16342-16358, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38316743

RESUMO

Green finance has great potential for supporting environmental improvement, combating climate change, and the economical and efficient use of resources. In this study, based on the panel data of 30 provinces in China from 2010 to 2020, we used the weighted TOPSIS model to measure the green finance development level (GFDL) in China and its three major regions. The Dagum's Gini coefficient, kernel density estimation, Markov chain, and the convergence model are used to analyze the regional differences, dynamic evolution, and spatial-temporal convergence of GFDL in China. The results show that, in general, the GFDL shows an upward trend, but the GFDL in various regions is unbalanced, which is characterized by the spatial distribution of "high in the southeast and low in the northwest" and "high in the coast and low in the inland". The overall difference of GFDL is showing an expanding trend, which is mainly caused by inter-regional difference. The absolute differences of GFDL between the overall country, the eastern region, and the western region are on a widening trend, while that in the central region is on a narrowing trend. In addition, the GFDLs between the overall country, the eastern region, and the western region have no significant σ convergence, while there is an obvious σ convergence trend in the central region. Further, the GFDLs in China and its three major regions have obvious absolute ß convergence trends and conditional ß convergence trends.


Assuntos
Mudança Climática , Desenvolvimento Econômico , China , Cadeias de Markov , Análise Espacial
10.
Int J Biol Macromol ; 262(Pt 2): 130077, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38346625

RESUMO

The SARS-CoV-2 main protease Mpro, essential for viral replication is an important drug target. It plays a critical role in processing viral polyproteins necessary for viral replication assembly. One of the predominant SARS-CoV-2 Mpro mutations of Omicron variant is Pro132His. Structurally, this mutation site is located ∼22 Å away from the catalytic site. The solved crystal structure of this mutant in complex with inhibitors as well as its reported catalytic efficiency did not show any difference with respect to the wild type. Thus, the mutation was concluded to be non-allosteric. Based on microsecond long MD simulation of the Pro132His mutant and wild type, we show that Pro132His mutation affects the conformational equilibrium with more population of conformational substates having open catalytic site, modulated by the dynamics of the catalytic site entry loop, implying the allosteric nature of this mutation. The structural analysis indicates that rearrangement of hydrogen bonds between His132 and adjacent residues enhances the dynamics of the linker, which in turn is augmented by the inherent dynamic flexibility of the catalytic pocket entry site due to the presence of charged residues. The altered dynamics leading to loss of secondary structures corroborate well with the reported compromised thermal stability.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , Domínio Catalítico , Simulação de Dinâmica Molecular , Inibidores de Proteases/química , Simulação de Acoplamento Molecular
11.
Heliyon ; 10(1): e23797, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38192782

RESUMO

Comprehensive quantitative assessment of China's urban industrial water use efficiency is effectively promote the green industrial development important steps in order to realize the overall development of high quality. Between 2009 and 2021, 290 in China based on ground level above the panel data of the city, this paper conducts research based on two principles of efficiency improvement and four models of efficiency analysis. The results show that: First, from the perspective of spatial differences, the integrated water use efficiency of urban industry in China presents a slow and uneven upward trend of "low in the east and high in the west, high in the middle and low in the north and south". Second, from the perspective of driving factors, population density and government public investment on the whole inhibit the development of this efficiency, while GDP development and technological innovation promote it. Third, from the perspective of dynamic evolution prediction, the phenomenon of "beggar-thy-neighbor" and "neighborly kindness" coexist. Therefore, the government should implement industrial water-saving measures according to local conditions, the society should improve the supervision of the behavior of wasting industrial water, and the enterprises should speed up the integration process of industrial primary and repeat water efficiency, so as to promote the comprehensive green transformation of the economy and society.

12.
BMC Health Serv Res ; 24(1): 23, 2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178099

RESUMO

OBJECTIVE: The outbreak of the COVID-19 pandemic has drawn attention from all sectors of society to the level of public health services. This study aims to investigate the level of public health service supply in the four major regions of Guangdong Province, providing a basis for optimizing health resource allocation. METHODS: This article uses the entropy method and panel data of 21 prefecture-level cities in Guangdong Province from 2005 to 2021 to construct the evaluation index system of public health service supply and calculate its supply index. On this basis, the standard deviation ellipse method, kernel density estimation, and Markov chain are used to analyze the spatiotemporal evolution trend of the public health service supply level in Guangdong Province. The Dagum Gini coefficient and panel regression model are further used to analyze the relative differences and the key influencing factors of difference formation. Finally, the threshold effect model is used to explore the action mechanism of the key factors. RESULTS: Overall, the level of public health service supply in Guangdong Province is on an upward trend. Among them, polarization and gradient effects are observed in the Pearl River Delta and Eastern Guangdong regions; the balance of public health service supply in Western Guangdong and Northern Mountainous areas has improved. During the observation period, the level of public health services in Guangdong Province shifted towards a higher level with a smaller probability of leapfrogging transition, and regions with a high level of supply demonstrated a positive spillover effect. The overall difference, intra-regional difference and inter-regional difference in the level of public health service supply in Guangdong Province during the observation period showed different evolutionary trends, and spatial differences still exist. These differences are more significantly positively affected by factors such as the level of regional economic development, the degree of fiscal decentralization, and the urbanization rate. Under different economic development threshold values, the degree of fiscal decentralization and urbanization rate both have a double threshold effect on the role of public health service supply level. CONCLUSION: The overall level of public health service supply in Guangdong Province has improved, but spatial differences still exist. Key factors influencing these differences include the level of regional economic development, the degree of fiscal decentralization, and the urbanization rate, all of which exhibit threshold effects. It is suggested that, in view of the actual situation of each region, efforts should be made to build and maintain their own advantages, enhance the spatial linkage of public health service supply, and consider the threshold effects of key factors in order to optimize the allocation of health resources.


Assuntos
Pandemias , Urbanização , Humanos , China/epidemiologia , Cidades , Serviços de Saúde
13.
J Environ Manage ; 351: 119953, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38181681

RESUMO

An in-depth analysis of the urban flood disaster level in response to different rainfall characteristics and Low Impact Development (LID) measures is of significant importance for addressing unfavorable management conditions and implementing effective flood control measures. This study proposes a dynamic urban flood simulation framework based on the Storm Water Management Model (SWMM) and Geographic Information System (GIS) spatial analysis, incorporating an active inundation seed search algorithm. The framework is calibrated and validated using nine historical urban flood events. Subsequently, the impact of rainfall patterns on urban inundation under LID measures is analyzed based on the dynamic urban flood simulation framework. The results show that the urban flood simulation framework exhibits good applicability, with Nash-Sutcliffe Efficiency (NSE) values of 0.825 and 0.763 during the calibration and validation periods, respectively. The extent of inundation shows little variation for rainfall events with a return period greater than 20 years, and the location of flooding is minimally affected by rainfall patterns. LID measures have a decreasing effect on urban inundation control as the return period of rainfall increases, and there are variations in hydrological responses to different rainfall patterns under the same return period. For single-peak rainfall events with the same return period, the control rates of inundation volume, flow, and infiltration decrease as the rainfall peak coefficient increases, indicating a weakening effect of LID measures on flood control with increasing rainfall peak coefficient. Under the same return period conditions, LID measures exhibit the best runoff control effect for uniform rainfall, while their effectiveness is lower for double-peak rainfall events and single-peak rainfall events with an r = 0.75 coefficient. The findings of this study provide a theoretical basis for urban flood warning and management of Low Impact Development measures.


Assuntos
Desastres , Inundações , Modelos Teóricos , Urbanização , Chuva , Cidades
14.
Molecules ; 29(2)2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38257388

RESUMO

A new approach is presented in this paper for the dynamic modeling of the chemical and isotopic evolution of C1-3 during the hydrocarbon generation process. Based on systematic data obtained from published papers for the pyrolysis of various hydrocarbon sources (type I kerogen/source rock, type II kerogen/source rock, type III kerogen/source rock, crude oil, and asphalt, etc.), the empirical evolution framework of the chemical and isotopic composition of C1-3 during the hydrocarbon generation process was built. Although the empirical framework was built only by fitting a large amount of pyrolysis data, the chemical and isotopic composition of C1-3 derived from the pyrolysis experiments all follow evolution laws, convincing us that it is applicable to the thermal evolution process of various hydrocarbon sources. Based on the simplified formula of the isotopic composition of mixed natural gas at different maturities (δ13Cmixed), δ13Cmixed = X×niA×δ13CiA+Y×niB×δ13CiBX×niA+Y×niB, it can be derived that the cumulative isotopic composition of alkane generated in a certain maturity interval can be expressed by the integral of the product of the instantaneous isotopic composition and instantaneous yield at a certain maturity point, and then divided by the cumulative yield of alkane generated in the corresponding maturity interval. Thus, the cumulative isotopic composition (A(X)), cumulative yield (B(X)), instantaneous isotope (C(X)), and instantaneous yield (D(x)) in the dynamic model, comply with the following formula during the maturity interval of (X0~X). A(X) = ∫X0XCX×DXdxB(X), where A(X) and B(X) can be obtained by the fitting of pyrolysis data, and D(x) can also be obtained from the derivation of B(X). The dynamic model was applied on the pyrolysis data of Pingliang Shale to illustrate the quantitative evolution of the cumulative yield, instantaneous yield, cumulative isotope, and instantaneous isotope of C1-3 with increasing maturity. The dynamic model can quantify the yield of methane, ethane, and propane, as well as δ13C1, δ13C2, and δ13C3, respectively, during the hydrocarbon generation process. This model is of great significance for evaluating the natural gas resources of hydrocarbon source rock of different maturities and for identifying the origin and evolutionary process of hydrocarbons by chemical and isotopic data. Moreover, this model provides an approach to study the dynamic evolution of the isotope series of C1-3 (including reversed isotopic series), which is promising for revealing the mechanism responsible for isotopic reversal when combined with post-generation studies.

15.
Angew Chem Int Ed Engl ; 63(6): e202318246, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38102742

RESUMO

Addressing the limitations arising from the consistent catalytic behavior observed for various intermediates during the electrochemical carbon dioxide reduction reaction (CO2 RR) poses a significant challenge in the optimization of catalytic activity. In this study, we aimed to address this challenge by constructing an asymmetric coordination Fe single atom catalyst (SCA) with a dynamically evolved structure. Our catalyst, consisting of a Fe atom coordinated with one S atom and three N atoms (Fe-S1 N3 ), exhibited exceptional selectivity (CO Faradaic efficiency of 99.02 %) and demonstrated a high intrinsic activity (TOF of 7804.34 h-1 ), and remarkable stability. Using operando XAFS spectra and Density Functional Theory (DFT) calculations, we elucidated the self-relaxation of geometric distortion and dynamic evolution of bond lengths within the catalyst. These structure changes enabled independent regulation of the *COOH and *CO intermediate adsorption energies, effectively breaking the linear scale relationship and enhancing the intrinsic activity of CO2 RR. This study provides valuable insights into the dynamic evolution of SACs and paves the way for targeted catalyst designs aimed to disrupt the linear scaling relationships.

16.
Environ Sci Pollut Res Int ; 30(54): 116186-116201, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37910353

RESUMO

Carbon emissions from animal agriculture are a major source of global greenhouse gases. This paper measures the spatial and temporal characteristics and evolution patterns of carbon emissions from livestock farming in China and 31 provinces from 2001 to 2020 based on IPCC coefficients. The paper also uses Moran's I index, kernel density estimation, and spatial Markov chains for the analysis. The results show that the total carbon emissions from China's livestock sector show a fluctuating downward trend. And livestock carbon emissions are concentrated in areas with better resource endowments, with grassland and grain-producing areas dominating China's livestock carbon emissions. The spatial analysis shows that the spatial correlation of the national livestock carbon emissions is increasing, showing prominent local aggregation characteristics, mainly in the form of high-high and low-low aggregation. The transfer of carbon emissions from China's livestock industry shows strong spatial and temporal dependence, and the transfer of regional carbon emissions is limited by the original type and stock of carbon emissions, showing growth inertia and path dependence. The findings of this paper can provide suggestions for planning and modifying policies to reduce carbon emissions in China's livestock industry.


Assuntos
Carbono , Gases de Efeito Estufa , Animais , Carbono/análise , Criação de Animais Domésticos , Análise Espacial , China , Gado , Dióxido de Carbono/análise , Desenvolvimento Econômico
17.
Environ Sci Pollut Res Int ; 30(58): 121993-122010, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37957497

RESUMO

Taking three major urban agglomerations in China as examples, this paper uses the Dagum Gini coefficient and its decomposition method, a Kernel density estimation method, and Markov chain and spatial Markov chain to study the regional differences, dynamic evolution characteristics, and spatial spillover effects of carbon emission intensity (CEI) of urban agglomerations, and accordingly, it proposes differentiated emission reduction and carbon reduction policies. The following results were obtained: (1) The overall CEI of the three major urban agglomerations and each individual urban agglomeration were found to have declined significantly over time, with an overall spatial pattern of "high in the north and low in the south," with inter-group differences being the main source of the overall differences. (2) The imbalance in CEI between cities was more obvious within the Beijing-Tianjin-Hebei (BTH) urban agglomeration, while the synergistic emission reduction effect of the Yangtze River Delta (YRD) and Pearl River Delta (PRD) urban agglomerations increased over the study period. (3) The probability of a city maintaining a stable level of CEI was much higher than the probability of a state shift, and there was a spatial spillover effect of carbon emissions between neighboring cities. This study can provide theoretical support for the global response to greenhouse gas emissions, promoting green development and carbon reduction in various countries and urban agglomerations and providing a quantitative basis for the formulation of relevant policies.


Assuntos
Carbono , Rios , Carbono/análise , Pequim , Cidades , China , Análise Espacial , Desenvolvimento Econômico
18.
Heliyon ; 9(11): e21438, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027848

RESUMO

To promote the coordinated development of high quality postgraduate education and economy is the realization of all-round construction of the socialist modernization of China power.Based on the panel data of 30 provinces in China from 2009 to 2021, this paper constructs the index of graduate education and high-quality economic development respectively, and analyzes it by coupling coordination model, kernel density estimation and spatial Markov chain model.The results show that: first, the postgraduate education and the high economic quality of most provinces in China are matched, but there is a significant difference between the eastern and western regions in their collaborative development; Second, the level of synergistic development between graduate education and high economic quality is low, and the central and northeastern regions are seriously divided, but the differences in synergistic effects between different regions are narrowing.Third, according to the results of trend prediction, there is the coexistence of "beggar-thy-neighbor" and "good-neighborliness", and it is difficult to achieve leapfrog coordinated development.Therefore, it is proposed to pay attention to the high-quality economic development to provide a rich material basis for graduate education, the change of graduate education structure should adapt to the needs of high-quality economic development, and implement different reform measures in different regions to promote the comprehensive construction of a modern socialist country.

19.
Front Public Health ; 11: 1222424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37869205

RESUMO

Objective: This study aims to analyze the spatial distribution and dynamic evolution of older adult service supply in Zhejiang Province from 2010 to 2019. Additionally, this research seeks to propose an optimized resource allocation strategy for older adult care services, promoting regional fairness and coordinated development. Methods: To evaluate the older adult service supply capacity, this research first constructed an evaluation index system based on the Chinese modernization development pattern. Then, an empirical analysis was carried out using a combination of the entropy-TOPSIS method, kernel density estimation, Markov chain analysis, Dagum Gini coefficient, and panel regression model. Results: The results show an overall upward trend in the supply and service capacity of older adult care in the whole province. However, the spatial distribution of older adult service supply capacity in Zhejiang Province still exhibits a gradient effect, even in the most recent year of 2019. Furthermore, the supply capacity of older adult services shifted to a higher level in the whole province, and regions with high supply capacity had a positive spillover effect on adjacent regions. The overall difference in the older adult service supply capacity of the province showed a decreasing trend. The level of economic development, urbanization rate, transportation capacity, the level of opening up, and the proportion of employees in the tertiary industry had a significant impact on the supply capacity and spatial difference of older adult services. Conclusion: From the findings, this study puts forth countermeasures and suggestions to optimize the spatial distribution of older adult care services. This includes giving full play to the regional spatial linkage effect, promoting new-type urbanization construction, upgrading the transportation network, and expanding the opening up of the industrial structure. By implementing these measures, a more equitable and coordinated older adult services system can be developed in Zhejiang Province.


Assuntos
Povo Asiático , Serviços de Saúde para Idosos , Alocação de Recursos , Idoso , Humanos , China , Desenvolvimento Econômico , Indústrias , Cadeias de Markov , Serviços de Saúde para Idosos/provisão & distribuição , Análise Espacial
20.
Adv Sci (Weinh) ; 10(32): e2301490, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37672878

RESUMO

Recently, all-solid-state sodium batteries (Na-ASSBs) have received increased interest owing to their high safety and potential of high energy density. The potential of Na-ASSBs based on sodium superionic conductor (NASICON)-structured Na3 V2 (PO4 )3 (Na3 VP) cathodes have been proven by their high capacity and a long cycling stability closely related to the microstructural evolution. However, the detailed kinetics of the electrochemical processes in the cathodes is still unclear. In this work, the sodiation/desodiation process of Na3 VP is first investigated using in situ high-resolution transmission electron microscopy (HRTEM). The intermediate Na2 V2 (PO4 )3 (Na2 VP) phase with the P21 /c space group, which would be inhibited by constant electron beam irradiation, is observed at the atomic scale. With the calculated volume change and the electrode-electrolyte interface after cycling, it can be concluded that the  Na2 VP phase reduces the lattice mismatch between Na3 VP and NaV2 (PO4 )3 (NaVP), preventing structural collapse. Based on the density functional theory calculation (DFT), the Na+ ion migrates more rapidly in the Na2 VP structure, which facilitates the desodiation and sodiation processes. The formation of  Na2 VP phase lowers the formation energy of NaVP. This study demonstrates the dynamic evolution of the Na3 VP structure, paving the way for an in-depth understanding of electrode materials for energy-storage applications.

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