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Article ; Online: Multiscale Analysis of the Highly Stretchable Carbon−Based Polymer Strain Sensor

Junpu Wang / Zhu Wang / Yanjiang Zuo / Wenzhi Wang

Polymers, Vol 15, Iss 1780, p

2023 Volume 1780

Abstract: In this paper, a multiscale analysis method was proposed to simulate carbon nanoparticles (CNPs)−filled polymers which can be strain sensors applied in wearable electronic devices, flexible skin, and health monitoring fields. On the basis of the ... ...

Abstract	In this paper, a multiscale analysis method was proposed to simulate carbon nanoparticles (CNPs)−filled polymers which can be strain sensors applied in wearable electronic devices, flexible skin, and health monitoring fields. On the basis of the microstructure characteristics of the composite, a microscale representative volume element model of the CNPs−filled polymer was established using the improved nearest−neighbor algorithm. By finite element analysis, the variation of the junction widths of adjacent aggregates can be extracted from the simulation results. Then, according to the conductive mechanism of CNP−filled polymers, the composite was simplified as a circuit network composed of vast random resistors which were determined by the junction widths between adjacent aggregates. Hence, by taking junction widths as the link, the resistance variation of the CNPs−filled polymer with the strain can be obtained. To verify the proposed method, the electromechanical responses of silicone elastomer filled with different CNPs under different filling amounts were investigated numerically and experimentally, respectively, and the results were in good agreement. Therefore, the multiscale analysis method can not only reveal the strain−sensing mechanism of the composite from the microscale, but also effectively predict the electromechanical behavior of the CNPs−filled polymer with different material parameters.
Keywords	keyword flexible strain sensor ; carbon nanoparticle−filled polymer ; representative volume element ; multiscale analysis ; Organic chemistry ; QD241-441
Subject code	540
Language	English
Publishing date	2023-04-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Synthesis and Properties of Polyamide 6 Random Copolymers Containing an Aromatic Imide Structure

Yingwei Zhang / Chunhua Wang / Yong Yi / Wenzhi Wang / Jun Yang

Polymers, Vol 15, Iss 2812, p

2023 Volume 2812

Abstract: In order to adjust the properties of polyamide 6 (PA6) and expand its application, a new strategy of introducing an aromatic imide structure into the PA6 chain through the random copolymerization method is reported. The diimide diacid monomer was first ... ...

Abstract	In order to adjust the properties of polyamide 6 (PA6) and expand its application, a new strategy of introducing an aromatic imide structure into the PA6 chain through the random copolymerization method is reported. The diimide diacid monomer was first synthesized by the dehydration and cyclization of pyromellitic dianhydride and 6-aminocaproic acid before it reacted with 1,6-hexamethylene diamine to form poly(amide imide) (PAI) salt, and finally synthesized PA6/PAI random copolymers containing an aromatic imide structure by the random copolymerization of ε-caprolactam and PAI salt. The introduction of an aromatic imide structural unit into the PA6 chain could have a great influence on its properties. As the content of PAI increases, the crystallinity ( X c ) and melting temperature ( T m ) of the PA6/PAI random copolymer gradually decrease, but its glass transition temperature ( T g ) increases obviously. When the PAI content is 20 wt%, the copolymer PA6/PAI-20 has the best comprehensive performance and not only has high thermal stabilities but also excellent mechanical properties (high strength, high modulus, and good toughness) and dielectric properties (low dielectric constant and dielectric loss). Moreover, these properties are significantly superior to those of PA6. Such high-performance PA6 random copolymers can provide great promise for the wider applications of PA6 materials.
Keywords	polyamide 6 ; poly(amide imide) ; random copolymerization ; Organic chemistry ; QD241-441
Subject code	540
Language	English
Publishing date	2023-06-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The impact of local government debt on urban environmental pollution and its mechanism

Zhenyu Qi / Siying Yang / Dawei Feng / Wenzhi Wang

PLoS ONE, Vol 17, Iss 3, p e

Evidence from China.

2022 Volume 0263796

Abstract: As an important financial means for governments to improve the quality of economic development, government debt greatly affects the quality of local environmental governance. Based on a theoretical mechanism analysis that uses the pollutant emissions ... ...

Abstract	As an important financial means for governments to improve the quality of economic development, government debt greatly affects the quality of local environmental governance. Based on a theoretical mechanism analysis that uses the pollutant emissions panel data and new caliber urban investment bond data of 273 cities in China, this paper empirically tests the impact of local government debt on urban emission reduction and the mechanism that drives this impact. We find that local government debt significantly promotes urban emissions reduction, and as urban pollution becomes more aggravated, this promoting effect has a dynamic path, first strengthening and then weakening. The role of local government debt in promoting urban emission reduction is characterized by both temporal and spatial heterogeneity. A mechanistic analysis shows that local government debt can promote urban emission reduction by promoting urban environmental innovation, with green invention patents demonstrating a stronger intermediary role than green utility model patents.
Keywords	Medicine ; R ; Science ; Q
Subject code	339
Language	English
Publishing date	2022-01-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: The impact of local government debt on urban environmental pollution and its mechanism

Zhenyu Qi / Siying Yang / Dawei Feng / Wenzhi Wang

PLoS ONE, Vol 17, Iss

Evidence from China

2022 Volume 3

Abstract	As an important financial means for governments to improve the quality of economic development, government debt greatly affects the quality of local environmental governance. Based on a theoretical mechanism analysis that uses the pollutant emissions panel data and new caliber urban investment bond data of 273 cities in China, this paper empirically tests the impact of local government debt on urban emission reduction and the mechanism that drives this impact. We find that local government debt significantly promotes urban emissions reduction, and as urban pollution becomes more aggravated, this promoting effect has a dynamic path, first strengthening and then weakening. The role of local government debt in promoting urban emission reduction is characterized by both temporal and spatial heterogeneity. A mechanistic analysis shows that local government debt can promote urban emission reduction by promoting urban environmental innovation, with green invention patents demonstrating a stronger intermediary role than green utility model patents.
Keywords	Medicine ; R ; Science ; Q
Subject code	339
Language	English
Publishing date	2022-01-01T00:00:00Z
Publisher	Public Library of Science (PLoS)
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: A Recognition Model Incorporating Geometric Relationships of Ship Components

Shengqin Ma / Wenzhi Wang / Zongxu Pan / Yuxin Hu / Guangyao Zhou / Qiantong Wang

Remote Sensing, Vol 16, Iss 1, p

2023 Volume 130

Abstract: Ship recognition with optical remote sensing images is currently widely used in fishery management, ship traffic surveillance, and maritime warfare. However, it currently faces two major challenges: recognizing rotated targets and achieving fine-grained ... ...

Abstract	Ship recognition with optical remote sensing images is currently widely used in fishery management, ship traffic surveillance, and maritime warfare. However, it currently faces two major challenges: recognizing rotated targets and achieving fine-grained recognition. To address these challenges, this paper presents a new model called Related-YOLO. This model utilizes the mechanisms of relational attention to stress positional relationships between the components of a ship, extracting key features more accurately. Furthermore, it introduces a hierarchical clustering algorithm to implement adaptive anchor boxes. To tackle the issue of detecting multiple targets at different scales, a small target detection head is added. Additionally, the model employs deformable convolution to extract the features of targets with diverse shapes. To evaluate the performance of the proposed model, a new dataset named FGWC-18 is established, specifically designed for fine-grained warship recognition. Experimental results demonstrate the excellent performance of the model on this dataset and two other public datasets, namely FGSC-23 and FGSCR-42. In summary, our model offers a new route to solve the challenging issues of detecting rotating targets and fine-grained recognition with remote sensing images, which provides a reliable foundation for the application of remote sensing images in a wide range of fields.
Keywords	optical remote sensing ; rotated ship recognition ; fine-grained ship dataset ; Science ; Q
Subject code	006
Language	English
Publishing date	2023-12-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Declining tree growth rates despite increasing water-use efficiency under elevated CO2 reveals a possible global overestimation of CO2 fertilization effect

Benjamin Laffitte / Barnabas C. Seyler / Wenzhi Wang / Pengbo Li / Jie Du / Ya Tang

Heliyon, Vol 8, Iss 10, Pp e11219- (2022)

2022

Abstract: Though rising atmospheric CO2 concentrations (Ca) harm the environment and society, they may also raise photosynthetic rates and enhance intrinsic water-use efficiency (iWUE). Numerous short-term studies have investigated tree growth under elevated CO2 ( ... ...

Abstract	Though rising atmospheric CO2 concentrations (Ca) harm the environment and society, they may also raise photosynthetic rates and enhance intrinsic water-use efficiency (iWUE). Numerous short-term studies have investigated tree growth under elevated CO2 (eCO2) conditions, but no long-duration study has investigated eCO2 impacts on tree growth and iWUE under natural conditions. Utilizing a new dendrochronological experimental design in a heavily-touristed nature preserve in Southwest China (Jiuzhaigou National Nature Reserve), we compared tree growth (e.g., basal area increment) and iWUE in two biophysically and environmentally similar valleys with contrasting anthropogenic activities. Trees in the control valley with ambient CO2 benefited from increasing Ca, possibly due to the CO2 fertilization effect and optimal environmental conditions. However, trees in the treatment valley with intensive tourism experienced comparatively higher localized eCO2 and growth rate declines. While iWUE increased (1959–2017) in the control (25.3%) and treatment sites (47.8%), declining tree growth rates in the treatment site was likely because comparatively extreme CO2 exposure levels encouraged stomatal closures. As the first long-term study investigating eCO2 impacts on tree growth and iWUE under natural conditions, we demonstrate that increased forest iWUE is unlikely to overcome negative drought stress and rising temperature impacts. Thus, forest potential for mitigating eCO2 and global climate change is likely overestimated, particularly under dry temperate conditions.
Keywords	Basal area increment ; CO2 fertilization effect ; Dendrochronology ; Elevated CO2 ; Intrinsic water-use efficiency ; Jiuzhaigou national nature reserve ; Science (General) ; Q1-390 ; Social sciences (General) ; H1-99
Subject code	580
Language	English
Publishing date	2022-10-01T00:00:00Z
Publisher	Elsevier
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Centrosomal Protein CEP135 Regulates the Migration and Angiogenesis of Endothelial Cells in a Microtubule-Dependent Manner

Kun Wang / Xin Wang / Fayun Zhao / Qiang Zhao / Shenke Kong / Peiyao Ma / Gang Wu / Wenzhi Wang / Xuejun Zhang

Frontiers in Bioscience-Landmark, Vol 28, Iss 11, p

2023 Volume 303

Abstract: Background: Angiogenesis is the formation of blood vessels by sprouting from mature blood vessels and is regulated by multiple factors; however, the role of centrosome and centrosomal proteins (CEP) in angiogenesis needs further study. centrosomal ... ...

Abstract	Background: Angiogenesis is the formation of blood vessels by sprouting from mature blood vessels and is regulated by multiple factors; however, the role of centrosome and centrosomal proteins (CEP) in angiogenesis needs further study. centrosomal protein 135 (CEP135) is an important centrosome-associated protein that can affect a variety of cellular processes, such as the cell cycle, but its effect on angiogenesis is still unknown. Methods: Tube formation and in vivo angiogenesis assays were performed to confirm the effects of CEP135 on endothelial cell (EC) angiogenesis in vitro and in mice. Cell counting kit-8 (CCK-8), 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry (FCM) and immunoblot assays were performed to confirm the effects of CEP135 on the proliferation and cell cycle of endothelial cells. Wound healing, transwell, and fluorescence staining were performed to confirm its effects on EC cell migration, polarization, and spindle orientation, and a tubulin turbidity assay was performed to confirm its effects on microtubule stabilization. Results: We conducted a series of experiments to explore the potential role of CEP135 in angiogenesis. CEP135 siRNA obviously inhibits angiogenesis in vivo compared with the control. CEP135 could mediate cell proliferation and the cell cycle by mediating spindle orientation. Moreover, we showed that CEP135 is involved in the regulation of angiogenesis by affecting the migration of endothelial cells using wound closure and transwell assays. We further demonstrated that CEP135 promotes endothelial polarization and microtubule stability, thus affecting cell migration. Conclusions: CEP135 was involved in the polarization of centrosomes, which is important for the migration of human umbilical vein ECs (HUVECs). These findings indicated that CEP135 may promote the polarization of HUVECs and accelerate migration, which in turn promotes angiogenesis.
Keywords	angiogenesis ; cep135 ; migration ; polarization ; endothelial cells ; Biochemistry ; QD415-436 ; Biology (General) ; QH301-705.5
Subject code	610
Language	English
Publishing date	2023-11-01T00:00:00Z
Publisher	IMR Press
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Experimentation of the Bilinear Elastic Behavior of Plain-Woven GFRP Composite with Embedded SMA Wires

Zhiwei Sun / Yingjie Xu / Wenzhi Wang

Polymers, Vol 11, Iss 3, p

2019 Volume 405

Abstract: In this paper, a plain-woven glass-fabric-reinforced polymer (GFRP) composite with embedded shape memory alloy (SMA) wires is investigated by means of experiments. The vacuum-assisted resin injection (VARI) method is utilized to fabricate the composite ... ...

Abstract	In this paper, a plain-woven glass-fabric-reinforced polymer (GFRP) composite with embedded shape memory alloy (SMA) wires is investigated by means of experiments. The vacuum-assisted resin injection (VARI) method is utilized to fabricate the composite specimens. Quasi-static uniaxial tensile tests are then carried out to evaluate the influence of SMA reinforcement on the stress–strain behavior of the composite. Only the elastic behavior of the composite is considered in the present study. The tensile strain in all the experiments is kept below 2.5% to avoid debonding of the SMA-resin interface, which would lead to failure of the composite. Stress–strain curves are obtained and shown to present a bilinear behavior due to phase transformation taking place in the SMA wires beyond a certain stress threshold.
Keywords	shape memory alloy ; GFRP composite ; plain-woven composite ; experiment ; elastic behavior ; Organic chemistry ; QD241-441
Subject code	669
Language	English
Publishing date	2019-03-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: High-Precision and Four-Dimensional Tracking System with Dual Receivers of Pipeline Inspection Gauge

Yue Long / Songling Huang / Lisha Peng / Wenzhi Wang / Shen Wang / Wei Zhao

Applied Sciences, Vol 11, Iss 3366, p

2021 Volume 3366

Abstract: Pipeline inspection gauges (PIGs) are widely used for nondestructive testing of oil and natural gas pipelines, while above ground markers (AGMs) can locate and track the PIG through a variety of methods, including magnetic flux leakage signals, acoustic ... ...

Abstract	Pipeline inspection gauges (PIGs) are widely used for nondestructive testing of oil and natural gas pipelines, while above ground markers (AGMs) can locate and track the PIG through a variety of methods, including magnetic flux leakage signals, acoustic signals, and extremely low-frequency (ELF) magnetic signals. Traditional AGMs have the disadvantages of low positioning accuracy and only one-dimensional tracking capability. In this paper, a newly-designed PIG tracking system based on the ELF magnetic field is proposed by assembling dual receivers. Moreover, this paper develops a magnetic field sign-integration algorithm to achieve high-precision and four-dimensional (4-D) tracking of PIG. The simulation and experiment results demonstrate that the tracking system has the capability of 4-D tracking. In comparison with the previously published work, the designed tracking system improves the positioning accuracy and orientation tracking accuracy by more than 50%. The dual receivers tracking system also has the characteristic of high-robustness. Even in the state of lateral offset or tilt, it can still achieve accurate tracking of PIG. The realization of PIG’s high-precision 4-D tracking can improve the accuracy of defect location. Moreover, it can also provide the latest pipeline network layout and facilitate pipeline maintenance and pipeline surveying applications.
Keywords	above ground marker ; dual tracking receivers ; extremely low frequency ; four-dimensional tracking ; magnetic field sign-integration algorithm ; pipeline inspection gauge ; Technology ; T ; Engineering (General). Civil engineering (General) ; TA1-2040 ; Biology (General) ; QH301-705.5 ; Physics ; QC1-999 ; Chemistry ; QD1-999
Subject code	600
Language	English
Publishing date	2021-04-01T00:00:00Z
Publisher	MDPI AG
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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Article ; Online: Multi-Factor Evaluation of Deep Karst Dolomite Reservoir Based on Paleogeomorphological Reconstruction, a Case Study From the 4th Member of the Dengying Formation in the Central Sichuan Basin, China

Zikun Zhou / Xingzhi Wang / Xiyan Yang / Long Wen / Wenzhi Wang / Deming Zeng / Mingyang Wei / Shengyang Xie / Fei Huo

Frontiers in Earth Science, Vol

2022 Volume 10

Abstract: The evaluation of reservoirs is of great importance in exploration practices, and reservoir distribution is dependent on multiple geological factors. The carbonate platform of the fourth member (Z2dn4) of the Dengying Formation (Z2dn) in the Gaoshiti- ... ...

Abstract	The evaluation of reservoirs is of great importance in exploration practices, and reservoir distribution is dependent on multiple geological factors. The carbonate platform of the fourth member (Z2dn4) of the Dengying Formation (Z2dn) in the Gaoshiti-Moxi area (GMA) was uplifted above sea level during episode II of the Tongwan movement and underwent prolonged karstification by meteoric freshwater in the terminal Sinian, leading to a strong heterogeneity in reservoirs. Paleogeomorphology reflects hydraulic gradients that can affect the intensities of surface karstification and may be approximated by terrain slope gradients. Karst products (especially solution vugs and caverns) exist prevailingly in the Z2dn4; their development mirrors the extents of internal dissolution. Based on paleogeomorphological reconstruction using the elevation method, the slope angles of single boreholes were calculated through the digital elevation model (DEM). In accordance with single-borewell Fullbore Formation MicroImager (FMI) logging data, four electrofacies (host rock, vug, fracture, and cave) were identified in boreholes possessing FMI data. The identified electrofacies were matched with corresponding conventional logging curves to obtain the training data. A model generalized for other boreholes without FMI data was established with the random forest algorithm and the thicknesses of the four electrofacies in each borehole were determined to characterize the extent of karstification. Slope gradients and electrofacies thicknesses, together with multiple physical parameters of reservoirs in boreholes, were utilized for factor analysis. Four factors were obtained and fused into one comprehensive score based on their ratios of variance proportions. The favorability of reservoirs was described by the comprehensive scores of each borehole. These analyses showed that the most advantageous reservoirs are distributed in the vicinity of the platform margin in the west of the GMA, where they enjoy several benefits. Deposition of porous ...
Keywords	reservoir evaluation ; paleogeomorphological reconstruction ; random forest algorithm ; factor analysis ; Deng member ; Gaoshiti-Moxi area ; Science ; Q
Subject code	550
Language	English
Publishing date	2022-06-01T00:00:00Z
Publisher	Frontiers Media S.A.
Document type	Article ; Online
Database	BASE - Bielefeld Academic Search Engine (life sciences selection)

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