Study on the urban digital transformation gyroscope model

Purpose – Urban digital transformation has become a key strategy in global countries. This study aims to provide a comprehensive and dynamic exploration of the intrinsic traits associated with urban digital transformation, in order to yield detailed insights that can contribute to the formulation of well-informed decisions and strategies in the field of urban development initiatives. Design/methodology/approach – Through analysis of parallels between urban digital transformation and gyroscope motion in physics, the study developed the urban digital transformation gyroscope model (UDTGM), which comprises of seven core elements. With the balanced panel dataset from 268 cities at and above the prefecture level in China, we validate the dynamic mechanism of this model. Findings – The findings of this study underscore that the collaboration among infrastructure development, knowledge-driven forces and economic operations markedly bolsters the urban digital transformation gyroscope’s efficacy. Practical implications – This research introduces a groundbreaking framework for comprehending urban digital transformation, potentially facilitating its balanced and systemic practical implementation. Originality/value – This study pioneers the UDTGM theoretically and verifies the dynamic mechanism of this model with real data

Injectable and Self-Healing Chitosan Hydrogel Based on Imine Bonds: Design and Therapeutic Applications

Biological tissues can automatically repair themselves after damage. Examples include skin, muscle, soft tissue, etc. Inspired by these living tissues, numerous self-healing hydrogels have been developed recently. Chitosan-based self-healing hydrogels constructed via dynamic imine bonds have been widely studied due to their simple preparation, good biocompatibility, and automatic reparability under physiological conditions. In this mini-review, we highlighted chitosan-based self-healing hydrogels based on dynamic imine chemistry, and provided an overview of the preparation of these hydrogels and their bioapplications in cell therapy, tumor therapy, and wound healing

Injectable and Self-Healing Chitosan Hydrogel Based on Imine Bonds: Design and Therapeutic Applications

Biological tissues can automatically repair themselves after damage. Examples include skin, muscle, soft tissue, etc. Inspired by these living tissues, numerous self-healing hydrogels have been developed recently. Chitosan-based self-healing hydrogels constructed via dynamic imine bonds have been widely studied due to their simple preparation, good biocompatibility, and automatic reparability under physiological conditions. In this mini-review, we highlighted chitosan-based self-healing hydrogels based on dynamic imine chemistry, and provided an overview of the preparation of these hydrogels and their bioapplications in cell therapy, tumor therapy, and wound healing

Application of FBG Sensor to Safety Monitoring of Mine Shaft Lining Structure

The use of fiber Bragg grating (FBG) sensors is proposed to solve the technical problem of poor sensor stability in the long-term safety monitoring of shaft lining structures. The auxiliary shaft of the Zhuxianzhuang coal mine was considered as the engineering background, and a test system implementing FBG sensors was established to monitor the long-term safety of the shaft lining structure. Indoor simulation testing revealed that the coefficient of determination (r2) between the test curves of the FBG sensor and the resistance strain gauge is greater than 0.99 in both the transverse and vertical strains. Therefore, the FBG sensor and resistance strain gauge test values are similar, and the error is small. The early warning value was obtained by calculation, according to the specific engineering geological conditions and shaft lining structure. The monitoring data obtained for the shaft lining at three test levels over more than three years reveal that the measured vertical strain value is less than the warning value, indicating that the shaft lining structure is currently in a safe state. The analysis of the monitoring data reveals that the vertical strain increment caused by the vertical additional force is approximately 0.0752 με/d. As the mine drainage progresses, the increasing vertical additional force acting on the shaft lining will compromise the safety of the shaft lining structure. Therefore, the monitoring must be enhanced to facilitate decision-making for safe shaft operation

Durable liquid-crystalline vitrimer actuators.

Vitrimer-based liquid-crystalline elastomers (LCEs) exhibit great advantages over the traditional LCEs due to their inherent processability to realize monodomain alignment and construction of LCE actuators with complex 3D structures in a robust way. Though exciting progress has been made, how to achieve a proper balance between processability and actuation durability/stability remains a big challenge. Here, we report a strategy to mitigate the conflict between processability and actuation stability by reducing the catalyst content in an epoxy/acid LCE vitrimer system. With a relatively low catalyst content (0.25 mol% to carboxyl group), monodomain LCEs with large actuation strain (∼95%) and excellent actuation stability (the actuation strain is completely maintained after 100 heating-cooling cycles and more than 90% of the initial strain is retained even after 500 cycles) could be easily prepared. Moreover, the monodomain LCEs can still be readily realigned or directly reconfigured into complex reversible 3D actuators

A durable monolithic polymer foam for efficient solar steam generation.

Efficient and cost-effective solar steam generation requires self-floating evaporators which can convert light into heat, prevent unnecessary heat loss and greatly accelerate evaporation without solar concentrators. Currently, the most efficient evaporators (efficiency of ∼80% under 1 sun) are invariably built from inorganic materials, which are difficult to mold into monolithic sheets. Here, we present a new polymer which can be easily solution processed into a self-floating monolithic foam. The single-component foam can be used as an evaporator with an efficiency at 1 sun comparable to that of the best graphene-based evaporators. Even at 0.5 sun, the efficiency can reach 80%. Moreover, the foam is mechanically strong, thermally stable to 300 °C and chemically resistant to organic solvents

Correction: A durable monolithic polymer foam for efficient solar steam generation.

[This corrects the article DOI: 10.1039/C7SC02967E.]

A durable monolithic polymer foam for efficient solar steam generation.

Efficient and cost-effective solar steam generation requires self-floating evaporators which can convert light into heat, prevent unnecessary heat loss and greatly accelerate evaporation without solar concentrators. Currently, the most efficient evaporators (efficiency of ∼80% under 1 sun) are invariably built from inorganic materials, which are difficult to mold into monolithic sheets. Here, we present a new polymer which can be easily solution processed into a self-floating monolithic foam. The single-component foam can be used as an evaporator with an efficiency at 1 sun comparable to that of the best graphene-based evaporators. Even at 0.5 sun, the efficiency can reach 80%. Moreover, the foam is mechanically strong, thermally stable to 300 °C and chemically resistant to organic solvents

Durable liquid-crystalline vitrimer actuators.

Vitrimer-based liquid-crystalline elastomers (LCEs) exhibit great advantages over the traditional LCEs due to their inherent processability to realize monodomain alignment and construction of LCE actuators with complex 3D structures in a robust way. Though exciting progress has been made, how to achieve a proper balance between processability and actuation durability/stability remains a big challenge. Here, we report a strategy to mitigate the conflict between processability and actuation stability by reducing the catalyst content in an epoxy/acid LCE vitrimer system. With a relatively low catalyst content (0.25 mol% to carboxyl group), monodomain LCEs with large actuation strain (∼95%) and excellent actuation stability (the actuation strain is completely maintained after 100 heating-cooling cycles and more than 90% of the initial strain is retained even after 500 cycles) could be easily prepared. Moreover, the monodomain LCEs can still be readily realigned or directly reconfigured into complex reversible 3D actuators

Correction: A durable monolithic polymer foam for efficient solar steam generation.

[This corrects the article DOI: 10.1039/C7SC02967E.]