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1.
Nano Lett ; 20(5): 3232-3239, 2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32338518

RESUMO

Signatures of Majorana zero modes (MZMs) have been observed in semiconductor nanowires (NWs) with a strong spin-orbital interaction (SOI) with proximity-induced superconductivity. Realizing topological superconductivity and MZMs in this platform requires eliminating spin degeneracy by applying a magnetic field. However, the field can adversely impact the induced superconductivity and places geometric restrictions on the device. These challenges could be circumvented by integrating magnetic elements with the NWs. Here, we report the first experimental investigation of spin transport across InSb NWs with ferromagnetic (FM) contacts. We observe signatures of spin polarization and spin-dependent transport in the quasi-one-dimensional ballistic regime. Moreover, we show that electrostatic gating tunes the observed magnetic signal and reveals a regime where the device acts as a spin filter. These results open an avenue toward developing MZM devices with spin degeneracy lifted locally without external fields. They could also enable spin-based devices that leverage spin-orbital states in quantum wires.

2.
Zhongguo Zhong Yao Za Zhi ; 40(6): 1219-22, 2015 Mar.
Artigo em Zh | MEDLINE | ID: mdl-26226774

RESUMO

The informatization of traditional Chinese medicine resources is the basis of modern medicine. With a spatial attribute traditional Chinese medicine resources could be carried out for in-depth spatial analysis, data mining and traditional Chinese medicine resources regional industrial layout. In this paper, we took the data of Glycyrrhiza uralensis in the third national Chinese medicine resources survey as the experimental data, described the principles and structure of traditional Chinese medicine resources spatial information database. We also described the establishment of analysis model with the help of this spatial database.


Assuntos
Bases de Dados Factuais , Plantas Medicinais/química , Mineração de Dados , Medicina Tradicional Chinesa
3.
Environ Sci Pollut Res Int ; 31(3): 4412-4424, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38102437

RESUMO

Exploring the relationship between poverty alleviation and carbon emissions can provide theoretical foundations for inclusive low-carbon development. This study empirically explores the impact of poverty alleviation on carbon emissions and its underlying mechanisms using panel data from Chinese provinces from 2007 to 2020. (1) The benchmark regression results indicate that poverty alleviation increases carbon emissions, and this result is robust. (2) Mechanism analysis reveals that promoting the transformation from the primary industry to the secondary industry and fostering consumption growth are important paths for poverty alleviation that promote carbon emissions. (3) Heterogeneity regression results show that effect of poverty alleviation on carbon emissions is more pronounced in impoverished provinces and resource-rich provinces. This study reveals the conflict between poverty alleviation and carbon emissions reduction in China, and reminds the government of the need to implement low-carbon poverty alleviation policies as well as guide people to low-carbon consumption.


Assuntos
Carbono , Pobreza , Humanos , Carbono/análise , China , Políticas , Benchmarking , Dióxido de Carbono/análise , Desenvolvimento Econômico
4.
Environ Sci Pollut Res Int ; 31(6): 8453-8466, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38175511

RESUMO

The Beijing-Tianjin-Hebei region is not only an important economic center in China, but also one of the major regions contributing to China's carbon emissions. Revealing the spatial distribution between carbon emissions and economic growth is essential for the formulation of low-carbon development policies. Following the principle from macro to micro, this paper investigates the spatial evolution trend and distribution characteristics between carbon emissions and economic growth in the Beijing-Tianjin-Hebei region from 2005 to 2020 by applying imbalance index model, the rank-scale rule, and decoupling index model. The results show that the imbalance index of carbon emissions decreased between 0.0601 and 0.0533 in a fluctuating way, indicating that the imbalance of spatial distribution of carbon emissions decreases. The imbalance index of economic growth increased between 0.0738 and 0.0851, indicating that economic growth has become more disequilibrated, and the spatial evolution of carbon emissions is not coordinated with economic growth. The Zipf dimension of carbon emissions declined from 1.1806 in 2005 to 0.9594 in 2020, and carbon emissions declined in big cities and increased in cities of the middle order. The Zipf dimension of economic growth increased from 1.1384 in 2005 to 1.2388 in 2020, and the economic growth monopoly in big cities increased. The decoupling coefficient of carbon emissions to economic growth declined, and the driving effect of economic growth on carbon emissions diminished. It is recommended that the Beijing-Tianjin-Hebei region should coordinate the allocation of factors and coordinate industrial adjustment. Hebei should accelerate industrial upgrading and establish a diversified industrial system.


Assuntos
Carbono , Desenvolvimento Econômico , Pequim , Carbono/análise , Cidades , China
5.
Environ Sci Pollut Res Int ; 31(21): 31373-31394, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38630406

RESUMO

The in-depth implementation of the "Broadband China Strategy" is of great significance in promoting the synergistic governance of urban carbon reduction and pollution reduction. In this paper, based on the "Broadband China" pilot program implemented in China in 2014 as a quasi-natural experiment, the coupled synergy model is used to measure the carbon and pollution reduction synergy index based on the balanced panel data of 277 prefectural-level cities and above in China from 2006 to 2020, and the staggered and synthetic DID methods are applied to investigate the impact of the Broadband China strategy on carbon and pollution reduction synergy and its mechanism. strategy on carbon and pollution reduction synergy and its mechanism. The conclusions of the study show that (1) the Broadband China strategy significantly improves the synergistic governance of carbon reduction and pollution reduction. (2) The mechanism results show that Broadband China mainly realizes carbon and pollution synergistic governance by promoting source control and process innovation but does not have an effective mediating role in end-of-pipe treatment. (3) The results of heterogeneity analysis show that Broadband China weakens the traditional geographic advantage, narrows the carbon pollution synergistic governance gap at the national and regional levels, and significantly improves the regional carbon reduction and pollution reduction governance level. This paper examines the micro-mechanism of the Broadband China strategy on carbon pollution synergistic governance from the whole process of production activities, which provides a new perspective for the study of carbon pollution synergistic governance, and provides an empirical basis for carbon pollution synergistic governance in China.


Assuntos
Carbono , China , Cidades , Poluição do Ar/prevenção & controle
6.
Environ Sci Pollut Res Int ; 30(43): 96726-96745, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37580478

RESUMO

In view of the problems of insufficient exploitation of carbon emission reduction potential and low-carbon emission reduction efficiency caused by the spatial mismatch of economy, society, and ecological environment, this study used the ArcGIS10.8 intuitive expression tool, the barycenter model, and the spatial mismatch index to systematically investigate the spatial-temporal pattern and its spatial mismatch characteristics of new energy consumption, industrial structure upgrading, and carbon carrying capacity in 30 provinces in China from 2009 to 2019. The findings of this study included mainly the following aspects. (1) The new energy consumption level showed the significant differences in spatial aggregation. The industrial structure upgrading level decreased from the southeast to the northwest. The carbon carrying state showed the gradual geographical evolution characteristics of the empty load, suitable basic load, suitable load, and overload from the southeast to the northwest. (2) The barycenter of new energy consumption shifted from the south to the north; the barycenter of industrial structure upgrading presented a phased migration trajectory of first to the northwest, then to the south, and then to the southwest; the barycenter of carbon carrying capacity oscillated from the southwest to the northeast. (3) Provinces with the positive mismatch of new energy consumption, industrial structure upgrading, and carbon carrying capacity were widely distributed, but provinces with the negative mismatch were sporadically distributed. The spatial mismatch degree of the three elements tended to expand on the whole, but the direction and magnitude of change were different. The high mismatch areas showed a trend of agglomeration in eastern coastal economic circles such as the Bohai Rim, the Yangtze River Delta, and the Pearl River Delta. Moreover, the high mismatch areas showed a trend of westward spread. (4) The contribution of province to the overall spatial mismatch decreased from the eastern to the western. This study would provide a reference for the related research on carbon peaking, carbon neutrality, and the coordinated high-quality development between economy-society and ecological environment.


Assuntos
Carbono , Conservação dos Recursos Naturais , Carbono/análise , Indústrias , Desenvolvimento Econômico , China , Cidades
7.
Environ Sci Pollut Res Int ; 30(45): 101280-101295, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37646925

RESUMO

This study used three batches of "broadband China" strategies (BCS) implemented from 2014 to 2016 as quasi-natural experiments (QE) to distinguish the level of urban digital infrastructure construction (DIC). Using 231 prefecture-level cities in China from 2011 to 2019 as research samples, a progressive differences-in-differences (DID) model was used to empirically test the relationship characteristics between DIC and urban carbon emission (CE) total and intensity. The results show that (1) DIC has a significant negative correlation with total carbon emissions (TCE) and carbon emission intensity (CI), which is conducive to the "dual control" of urban CE, which is still valid after the five robustness tests. (2) The mechanism test shows that the DIC is conducive to improving the level of formal environmental regulation (FER) and informal environmental regulation (IER) and strengthening the synergy between formal and informal environmental regulation (ER), so as to achieve "dual control" of carbon emissions, of which the synergy is the most significant, followed by FER. (3) In heterogeneity research findings, only the third batch of pilot projects can achieve "dual control" of CE, which has the advantage of latecomers. The "dual control" effect of carbon emissions in DIC is more significant in cities with higher levels of marketization and eastern cities. Therefore, DIC plays the role of "icing on the cake," not "providing charcoal in the snow."


Assuntos
Carbono , Carvão Vegetal , China , Cidades , Alimentos , Desenvolvimento Econômico , Dióxido de Carbono
8.
Environ Sci Pollut Res Int ; 29(14): 21023-21033, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34748180

RESUMO

The distribution of soil pollutants is receiving increasing attention. The accurate determination of the soil pollution distribution in an area is becoming more important. To date, many soil quality surveys have already been carried out in China, and the use of these surveys to reflect soil pollution is worth examining. This article provides an example of the application of combined two-phase data to assess soil contamination in a region. Based on data acquired during two soil sampling phases in 2005 and 2015, we chose a typical watershed in southeast China as the study area. We analysed the data using spatial interpolation analysis, compared the results, and extracted points to perform point combination based on site conditions. Ultimately, these analyses allowed us to develop a new method involving the use of multi-period data to evaluate the soil quality on a regional scale. In the ten years from 2005 to 2015, apparent changes in soil pollution occurred. We found that the area with no change in soil pollution accounts for 46.98% of the total basin and the area demonstrating a soil pollution increase accounts for 47.25% of the total basin, while the area exhibiting a soil pollution reduction only accounts for 5.78% of the whole area. The average accuracy of the combined points increased to 89% from 76 and 81%. The analysis of the land-use types and spatial locations during the two periods revealed no direct relationship between the soil contamination changes and the changes in the total number of land-use types, but a correlation was observed with the intensity of human activities at the spatial locations. This paper proposes a new method for the spatial assessment of soil pollution based using multiple periods of existing data on the above analysis.


Assuntos
Poluentes do Solo , Solo , China , Monitoramento Ambiental , Poluição Ambiental/análise , Humanos , Poluentes do Solo/análise , Análise Espacial
9.
Artigo em Inglês | MEDLINE | ID: mdl-35682259

RESUMO

With the accelerated development of urbanization in China, rural permanent population has declined, while rural electricity consumption has increased, resulting in a significant waste of electricity resources. Based on the provincial panel data of China from 2007 to 2020, this paper comprehensively used the decoupling model and the coordination degree model to analyze the temporal change characteristics, spatial distribution characteristics, and the degree of deviation of rural permanent population and rural electricity consumption. Firstly, according to the decoupling model, the type of decoupling between rural electricity consumption and rural permanent population was strong negative decoupling. At the provincial level, Beijing and Tibet belonged to expanding negative decoupling. Tianjin and Liaoning belonged to recession link. The other 27 provinces, including Hebei, Shanxi, and Shandong, belonged to strong negative decoupling. Secondly, according to the coordination degree model, the coordination type of the national rural permanent population and rural electricity consumption was uncoordinated. The areas that can be coordinated include 20 provinces, including Shanghai, Inner Mongolia, Jilin, Jiangsu, Anhui, Fujian, and Jiangxi. The basic coordination areas included Beijing and Tibet. Finally, according to the comprehensive measurement model, the provinces with strong negative decoupling included Shanxi, Zhejiang, and Chongqing. Sichuan, Hebei, Shandong, and Shaanxi belonged to moderately strong negative decoupling groups.


Assuntos
População Rural , Urbanização , China/epidemiologia , Demografia , Eletricidade , Humanos
10.
Front Public Health ; 10: 985576, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36091539

RESUMO

The Chinese Plan has provided an important model for the global fight against COVID-19 since its outbreak. The present study describes the structural characteristics of China's COVID-19 patent cooperation network at the province, city, and applicant levels by using social network analysis based on data from the Incopat global patent database since 2020, which helps to clarify the current technology accumulation in this field in China, and provide patent information support for the scientific efforts to fight against COVID-19. The findings are as follows: First, the inter-regional cooperation level in China's COVID-19 patent cooperation network shows a decreasing trend from eastern to central to western regions. At the inter-applicant cooperation level, kinship-based cooperation is the strongest, business-based cooperation has the widest scope, while proximity-based cooperation exists throughout these two main models of cooperation. Second, coastal provinces and cities occupy a core position in the network, and play an important role in utilizing structural holes and bridging. Patent applicants with high centrality are mostly firms. Research institutes and universities mainly play the role of bridges. Third and lastly, there is no large number of cliques at the province and city levels. However, there is a tendency for cliques to develop at the applicant level. Hence, actions are needed to prevent the development of information barriers.


Assuntos
COVID-19 , COVID-19/epidemiologia , China/epidemiologia , Cidades , Humanos , Rede Social
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