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  1. Article ; Online: The political economy of endogenous dual-sector model

    Yongqin Wang / Xin Gao

    China Political Economy, Vol 5, Iss 2, Pp 165-

    public goods, labor markets and tax rates

    2022  Volume 183

    Abstract: Purpose – This paper studies the political economy of the endogenous urban–rural divide in two dimensions: labor market and provision of public goods. Design/methodology/approach – This paper gives a dual-sector model endogenously depending on the ... ...

    Abstract Purpose – This paper studies the political economy of the endogenous urban–rural divide in two dimensions: labor market and provision of public goods. Design/methodology/approach – This paper gives a dual-sector model endogenously depending on the consumption of public goods (club goods), the number of rural–urban migrants and the tax rate (transfer payments). Findings – According to the research findings in this paper, the constraints on the participation of rural residents portray the rural residents' bargaining power, and in the game between the urban elites and the rural residents, tax rates depend on the preferences of the urban elites and the constraints urban elites and the rural residents jointly face. Therefore, the urban elites have to set tax rates deviating from the most preferred ones. The model in this paper can explain a series of empirical findings and yield new theoretical findings for empirical testing. Originality/value – Significantly, the paper finds that the increase in agricultural productivity will lead to industrialization, accompanied by the disintegration of the dual-sector model. However, though the increase in industrial productivity can accelerate industrialization, it will further expand the urban–rural divide.
    Keywords Congestion effect ; Two-sector model ; Urban bias ; Political economy ; Social Sciences ; H ; Finance ; HG1-9999
    Subject code 336
    Language English
    Publishing date 2022-12-01T00:00:00Z
    Publisher Emerald Publishing
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article ; Online: Method of defining rock damage variable on the basis of wave impedance

    Weiyu Li / Shizheng Fang / Xin Gao / Yidan Han

    Energy Science & Engineering, Vol 11, Iss 10, Pp 3641-

    2023  Volume 3661

    Abstract: Abstract A method of determining rock damage variable from wave impedance, which is suitable for the study of dynamics, is presented. The determined variable provides a more reasonable quantitative description of the degree of rock damage. First, the ... ...

    Abstract Abstract A method of determining rock damage variable from wave impedance, which is suitable for the study of dynamics, is presented. The determined variable provides a more reasonable quantitative description of the degree of rock damage. First, the Taylor model of mesoscopic damage mechanics is used to derive the relationship between the velocity of longitudinal waves and the density of rock materials. Based on the measured data of rock samples with different lithology and the same lithology, the relationship between the longitudinal wave velocity and density of rock materials is studied. It is demonstrated that using the wave impedance to define the rock damage variable has advantages over using the P‐wave velocity. Second, the relationship between the wave impedance and degree of damage to the rock material is studied using an electron microscope and ultrasonic testing technology, and the microstructure of rock samples with a wave impedance gradient and time–frequency‐domain characteristics of the ultrasonic signals are compared and analyzed. It is found that it is feasible to determine the damage degree of the rock from the wave impedance. Finally, a method of defining rock damage variable with the wave impedance is further proposed and its rationality verified. The research results show that there is a good positive correlation between the longitudinal wave velocity and density of rock materials, and there is a strong correlation between the degree of rock damage and its wave impedance. The damage variable defined by wave impedance can better reflect the damage state and damage evolution process of rock.
    Keywords damage variable ; meso damage ; rock mechanics ; ultrasonic longitudinal wave ; wave impedance ; Technology ; T ; Science ; Q
    Subject code 535
    Language English
    Publishing date 2023-10-01T00:00:00Z
    Publisher Wiley
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Characteristics of Dust Weather in the Tarim Basin from 1989 to 2021 and Its Impact on the Atmospheric Environment

    Yongchao Zhou / Xin Gao / Jiaqiang Lei

    Remote Sensing, Vol 15, Iss 1804, p

    2023  Volume 1804

    Abstract: Dust emission is a common catastrophic weather phenomenon in Northern China. This phenomenon not only causes environmental problems, such as air pollution, but also has an important impact on the global dust cycle and climate change. On the basis of the ... ...

    Abstract Dust emission is a common catastrophic weather phenomenon in Northern China. This phenomenon not only causes environmental problems, such as air pollution, but also has an important impact on the global dust cycle and climate change. On the basis of the dust weather observation data of 44 surface meteorological stations in the Tarim Basin from 1989 to 2021, combined with the dust aerosol optical depth (DAOD), dust surface mass concentration (DUSMASS) and wind speed data, this paper analyses the spatial and temporal dust weather characteristics in the Tarim Basin over the past 33 years. Results show that the frequency of dust weather in the Tarim Basin has declined in the past 33 years. Dust weather mainly consisted of floating dust, followed by blowing dust and dust storm. This weather had a significant seasonal change, with more dust in spring and summer and less in autumn and winter. The dust weather was mainly distributed along the south edge of the Tarim Basin and the desert hinterland of Tazhong. The spatial distribution of the dust intensity (DI) index was basically consistent with the dust weather days. Moreover, the DAOD was obviously affected by dust weather and had a significant positive correlation with the number of dust weather days and the DI, suggesting the vertical concentration of dust particles to a certain extent. Wind is also one of the most important factors affecting the release of dust. The frequency of strong wind weather decreases from the northeast to the southwest, which corresponds to the distribution of the DUSMASS.
    Keywords dust weather ; dust intensity index ; dust aerosol optical depth ; dust surface mass concentration ; wind conditions ; Science ; Q
    Subject code 520 ; 333
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article ; Online: Antibacterial Activity and Antibacterial Mechanism of Lemon Verbena Essential Oil

    Xin Gao / Jinbao Liu / Bo Li / Jing Xie

    Molecules, Vol 28, Iss 3102, p

    2023  Volume 3102

    Abstract: The destructive effect and mode of action of lemon verbena essential oil on cells were investigated, taking the isolated Pseudosciaena D4 as the research object. The extracellular absorbance of the Pseudosciaena D4 increased at OD260 and OD280 after ... ...

    Abstract The destructive effect and mode of action of lemon verbena essential oil on cells were investigated, taking the isolated Pseudosciaena D4 as the research object. The extracellular absorbance of the Pseudosciaena D4 increased at OD260 and OD280 after being treated with lemon verbena essential oil, which destroyed the integrity of Pseudosciaena D4 cells, showing a significant effect on preventing biomembrane formation and destroying the formed biomembrane. With an increased concentration of lemon verbena essential oil, extracellular polysaccharide showed a significant decrease in content and a significant increase in inhibition rate, indicating that the secretion of extracellular polysaccharide by Pseudosciaena D4 cells could be inhibited by lemon verbena essential oil during the process of biomembrane formation. Cell introcession and shrinkage appeared after the treatment with essential oil, and a transparent cavity was formed by the out-flowed cell content. Lemon verbena essential oil destroyed the cell wall, resulting in an enhanced permeability of the cell membrane and leakage of the contents, thereby causing cell death.
    Keywords lemon verbena essential oil ; antibacterial activity ; antibacterial mechanism ; Pseudosciaena crocea ; Organic chemistry ; QD241-441
    Subject code 571
    Language English
    Publishing date 2023-03-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  5. Article ; Online: Experimental Investigation on the Influence of Wave Impedance on Dynamic Mechanical Response of Granites undergone High Temperature

    Weiyu Li / Shizheng Fang / Xin Gao

    ACS Omega, Vol 8, Iss 45, Pp 42398-

    2023  Volume 42408

    Keywords Chemistry ; QD1-999
    Language English
    Publishing date 2023-11-01T00:00:00Z
    Publisher American Chemical Society
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Article ; Online: Synergistic Ball Milling–Enzymatic Pretreatment of Brewer’s Spent Grains to Improve Volatile Fatty Acid Production through Thermophilic Anaerobic Fermentation

    Can Liu / Ahamed Ullah / Xin Gao / Jian Shi

    Processes, Vol 11, Iss 1648, p

    2023  Volume 1648

    Abstract: Brewer’s spent grain (BSG) as the major byproduct in the brewing industry is a promising feedstock to produce value-added products such as volatile fatty acids (VFAs). Synergistic ball mill–enzymatic hydrolysis (BM-EH) process is an environmentally ... ...

    Abstract Brewer’s spent grain (BSG) as the major byproduct in the brewing industry is a promising feedstock to produce value-added products such as volatile fatty acids (VFAs). Synergistic ball mill–enzymatic hydrolysis (BM-EH) process is an environmentally friendly pretreatment method for lignocellulosic materials before bioprocessing. This study investigated the potential of raw and BM-EH pretreated BSG feedstocks to produce VFAs through a direct thermophilic anaerobic fermentation process without introducing a methanogen inhibitor. The highest VFA concentration of over 30 g/L was achieved under the high-solid loading fermentation (HS) of raw BSG. The synergistic BM-EH pretreatment helps to increase the cellulose conversion to 70%. Under conventional low TS fermentation conditions, compared to the controlled sample, prolonged pretreatment of the BSG substrate resulted in increased VFA yields from 0.25 to 0.33 g/g VS , and butyric acid became dominant instead of acetic acid.
    Keywords brewer’s spent grain ; ball mill–enzymatic hydrolysis pretreatment ; thermophilic anaerobic fermentation ; volatile fatty acid profile ; Chemical technology ; TP1-1185 ; Chemistry ; QD1-999
    Language English
    Publishing date 2023-05-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: Multiscale Efficient Channel Attention for Fusion Lane Line Segmentation

    Kang Liu / Xin Gao

    Complexity, Vol

    2021  Volume 2021

    Abstract: The use of multimodal sensors for lane line segmentation has become a growing trend. To achieve robust multimodal fusion, we introduced a new multimodal fusion method and proved its effectiveness in an improved fusion network. Specifically, a multiscale ... ...

    Abstract The use of multimodal sensors for lane line segmentation has become a growing trend. To achieve robust multimodal fusion, we introduced a new multimodal fusion method and proved its effectiveness in an improved fusion network. Specifically, a multiscale fusion module is proposed to extract effective features from data of different modalities, and a channel attention module is used to adaptively calculate the contribution of the fused feature channels. We verified the effect of multimodal fusion on the KITTI benchmark dataset and A2D2 dataset and proved the effectiveness of the proposed method on the enhanced KITTI dataset. Our method achieves robust lane line segmentation, which is 4.53% higher than the direct fusion on the precision index, and obtains the highest F2 score of 79.72%. We believe that our method introduces an optimization idea of modal data structure level for multimodal fusion.
    Keywords Electronic computers. Computer science ; QA75.5-76.95
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher Hindawi-Wiley
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  8. Article ; Online: Reverse Logistics Network Construction of Waste Electronic Products

    Ning Zheng / Xin Gao

    E3S Web of Conferences, Vol 275, p

    2021  Volume 02050

    Abstract: The acceleration of the updating and iteration of electronic products leads to the increasing types and quantity of waste electronic products, which poses a great threat to environmental protection and social development. The problem of reverse logistics ...

    Abstract The acceleration of the updating and iteration of electronic products leads to the increasing types and quantity of waste electronic products, which poses a great threat to environmental protection and social development. The problem of reverse logistics of waste electronic products has gradually become the focus of social attention. This paper constructed the expected value model of the reverse logistics of waste electronic products based on the open loop supply chain, and made the implementation plan of the reverse logistics through the empirical analysis of the electronic and electrical appliances market in H city.
    Keywords Environmental sciences ; GE1-350
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher EDP Sciences
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article ; Online: Analysis of the effects of related fingerprints on molecular similarity using an eigenvalue entropy approach

    Hiroyuki Kuwahara / Xin Gao

    Journal of Cheminformatics, Vol 13, Iss 1, Pp 1-

    2021  Volume 12

    Abstract: Abstract Two-dimensional (2D) chemical fingerprints are widely used as binary features for the quantification of structural similarity of chemical compounds, which is an important step in similarity-based virtual screening (VS). Here, using an eigenvalue- ...

    Abstract Abstract Two-dimensional (2D) chemical fingerprints are widely used as binary features for the quantification of structural similarity of chemical compounds, which is an important step in similarity-based virtual screening (VS). Here, using an eigenvalue-based entropy approach, we identified 2D fingerprints with little to no contribution to shaping the eigenvalue distribution of the feature matrix as related ones and examined the degree to which these related 2D fingerprints influenced molecular similarity scores calculated with the Tanimoto coefficient. Our analysis identified many related fingerprints in publicly available fingerprint schemes and showed that their presence in the feature set could have substantial effects on the similarity scores and bias the outcome of molecular similarity analysis. Our results have implication in the optimal selection of 2D fingerprints for compound similarity analysis and the identification of potential hits for compounds with target biological activity in VS.
    Keywords Structure-activity relationship ; Similarity-based virtual screening ; 2D fingerprint ; Unsupervised feature selection ; Chemoinformatics ; Information technology ; T58.5-58.64 ; Chemistry ; QD1-999
    Subject code 540
    Language English
    Publishing date 2021-03-01T00:00:00Z
    Publisher BMC
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  10. Article ; Online: Evaluation of Viscosity Changes and Rheological Properties of Diutan Gum, Xanthan Gum, and Scleroglucan in Extreme Reservoirs

    Xin Gao / Lixin Huang / Jianlong Xiu / Lina Yi / Yongheng Zhao

    Polymers, Vol 15, Iss 21, p

    2023  Volume 4338

    Abstract: The chemically synthesized polymer polyacrylamide (HPAM) has achieved excellent oil displacement in conventional reservoirs, but its oil displacement is poor in extreme reservoir environments. To develop a biopolymer oil flooding agent suitable for ... ...

    Abstract The chemically synthesized polymer polyacrylamide (HPAM) has achieved excellent oil displacement in conventional reservoirs, but its oil displacement is poor in extreme reservoir environments. To develop a biopolymer oil flooding agent suitable for extreme reservoir conditions, the viscosity changes and rheological properties of three biopolymers, diutan gum, xanthan gum, and scleroglucan, were studied under extreme reservoir conditions (high salt, high temperature, strong acid, and alkali), and the effects of temperature, mineralization, pH, and other factors on their viscosities and long-term stability were analyzed and compared. The results show that the three biopolymers had the best viscosity-increasing ability at temperatures of 90 °C and below. The viscosity of the three biopolymers was 80.94 mPa·s, 11.57 mPa·s, and 59.83 mPa·s, respectively, when the concentration was 1500 mg/L and the salinity 220 g/L. At the shear rate of 250 s −1 , 100 °C~140 °C, scleroglucan had the best viscosification. At 140 °C, the solution viscosity was 19.74 mPa·s, and the retention rate could reach 118.27%. The results of the long-term stability study showed that the solution viscosity of scleroglucan with a mineralization level of 220 mg/L was 89.54% viscosity retention in 40 days, and the diutan gum could be stabilized for 10 days, with the viscosity maintained at 90 mPa·s. All three biopolymers were highly acid- and alkali-resistant, with viscosity variations of less than 15% in the pH3~10 range. Rheological tests showed that the unique double-helix structure of diutan gum and the rigid triple-helix structure of scleroglucan caused them to have better viscoelastic properties than xanthan gum. Therefore, these two biopolymers, diutan gum, and scleroglucan, have the potential for extreme reservoir oil displacement applications. It is recommended to use diutan gum for oil displacement in reservoirs up to 90 °C and scleroglucan for oil displacement in reservoirs between 100 °C and 140 °C.
    Keywords diutan gum ; xanthan gum ; scleroglucan ; rheological behavior ; extreme reservoir ; long-term stability ; Organic chemistry ; QD241-441
    Subject code 660
    Language English
    Publishing date 2023-11-01T00:00:00Z
    Publisher MDPI AG
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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