Search Results (875)

Robotic grippers play a crucial role in pick-and-place tasks, as their performance directly affects the robot’s operational efficiency, stability, and safety. In industrial applications, such as coal gangue sorting, the target objects have irregular shapes and sharp surfaces, which pose challenges to the gripper’s grasping ability. To solve these problems, an adaptive under-actuated gripper based on rope control is designed. The gripper is simple to control and combines the excellent features of both rigid and flexible grippers. To analyze the characteristics of the gripper, both mathematical analysis and holding force experiments are conducted. The results show that the gripper can generate a greater holding force when grasping larger objects with a constant input air pressure. Furthermore, irregularly shaped testing objects, including coal lumps and ores, are selected to conduct grasping experiments. The gripper achieves a 100% grasping success rate with a load of up to four times the object’s weight suspended beneath it and shows the ability to reliably grasp irregularly shaped objects in high-speed pick-and-place tasks with a payload of four times the object’s weight. Meanwhile, the gripper has a passive anti-collision ability due to the special outer contour of the distal finger when subjected to unexpected, sudden force. Full article

Unconventional low-permeability reservoirs present significant production challenges due to the poor imbibition and displacement efficiency of conventional polymer fracturing fluids. The injection of nanoparticle (NP) compounds into polymer fracturing fluid base systems, such as linear gels or slickwater, has garnered significant research interest due to their superior performance. However, previous studies have primarily focused on evaluating the fluid’s properties, while its imbibition and oil displacement mechanisms within reservoirs remain unclear. Herein, the imbibition mechanism of nanoparticle composite polymer fracturing fluid was systematically investigated from macro and micro perspectives using low-field nuclear magnetic resonance (LF-NMR), atomic force microscopy (AFM), interfacial rheology, and other technical means. The results showed that the imbibition recovery using polymer fracturing fluid was 10.91% higher than that achieved with conventional slickwater. Small and medium pores were identified as the primary contributors to oil drainage. Nanoparticles can be adsorbed on the rock wall in the deep reservoir to realize wettability reversal from oil-wet to water-wet, reducing crude oil adhesion. Furthermore, a strong interaction between the adsorbed NPs and cleanup agents at the oil–water interface was observed, which reduces interfacial tension to 0.95 mN·m⁻¹, mitigates the Jamin effect, and enhances interfacial film deformability. NPs increase the interfacial dilatational modulus from 6.0 to 14.4 mN·m⁻¹, accelerating fluid exchange and oil stripping. This work provides a consolidated mechanistic framework linking NP-induced interfacial modifications to enhanced pore-scale drainage, offering a scientific basis for designing next-generation fracturing fluids. We conclude that NP-compound systems hold strong potential for low-permeability reservoir development, and future efforts must focus on optimizing NP parameters for specific reservoir conditions and overcoming scalability challenges for field deployment. Full article

As a key mechanism for guiding capital flows into green and low-carbon sectors, green finance plays a significant role in supporting China’s “dual carbon” strategy and driving the high-quality development of its energy system. This research investigates the mechanisms and effects through which green finance influences new-quality productivity in the energy sector. Based on Chinese provincial panel data spanning 2012–2022, we apply fixed-effects models, mediation effect tests, and a threshold regression model to empirically analyze the transmission channels, nonlinear features, and regional heterogeneities of this influence. The findings indicate the following: (1) Green finance significantly drives the development of new-quality productivity in the energy sector, and this conclusion holds robust after a series of robustness tests. (2) The primary transmission channels operate by promoting technological innovation and enhancing the level of foreign trade openness. (3) The impact presents nonlinear characteristics: the positive effect of green finance weakens when the level of technological innovation is excessively low or when foreign trade openness is overly high. (4) Significant heterogeneity is observed, with a more pronounced promotional effect in regions with weaker financial endowment, while the effect is relatively limited in regions with stronger financial endowment. Accordingly, this research proposes optimizing the green financial system and formulating differentiated regional policies to synergistically advance the development of new-quality productive forces in energy. Full article

Investigating how climatic and hydrological conditions in ecological resource-enriched zones of marginal seas respond to external forcing, particularly during past greenhouse climates, holds considerable significance for understanding current environmental and resource challenges driven by global warming. In marginal seas, climatic hydrological states, including salinity, redox conditions, and productivity, are key environmental parameters controlling organic matter production, preservation, and ultimately the formation of high-quality shale. Herein, high-resolution cyclostratigraphic and multi-proxy geochemical analyses were conducted on a continuous core from the upper part of Member 4 of the Eocene Shahejie Formation (Es4cu) in Well NY1, Dongying Sag, Bohai Bay Basin. Based on these data, a refined astronomical timescale was accordingly established for the studied interval. By integrating sedimentological observations with multiple proxy indicators, including elemental geochemistry (e.g., Sr/Ba and Ca/Al ratios), organic geochemistry, and mineralogical data, the evolution of climate and paleo-water mass conditions during the study period was reconstructed. Spectral analyses revealed prominent astronomical periodicities in paleosalinity, productivity, and redox proxies, indicating that sedimentation was modulated by cyclic changes in eccentricity, obliquity, and precession. It was hereby proposed that orbital forcing governed periodic shifts in basin hydrology by regulating the intensity and seasonality of the East Asian monsoon. Intervals of enhanced summer monsoon associated with high eccentricity and obliquity were typically accompanied by increased sediment supply and intensified chemical weathering. Increased precipitation and runoff raised the lake level while promoting stronger connectivity with the ocean. In contrast, during weak seasonal monsoon intervals linked to eccentricity minima, basin conditions shifted from humid to arid, characterized by reduced precipitation, lower lake level, decreased sediment supply, and a concomitant decline in proxies for water salinity. The present results demonstrated orbital forcing as a primary external driver of cyclical changes in conditions favorable for resource formation in the Eocene lacustrine strata of the Bohai Bay Basin. Overall, this study yields critical paleoclimate evidence and a mechanistic framework for predicting the spatial-temporal distribution of high-quality shale under comparable astronomical-climate boundary conditions. Full article

The emergence of artificial intelligence as a transformative force in the field of information technology has exerted a significant impact on the development of renewable energy. In-depth analysis of the impact of AI on renewable energy development is crucial for promoting energy transition and facilitating sustainable development. This research utilizes a dataset comprising 30 provincial panels spanning from 2010 to 2023. This study found that AI technology can promote renewable energy development, a conclusion that still holds after robustness and endogeneity tests. An examination of the mechanism reveals that AI technology facilitates the advancement of renewable energy through the enhancement of trade openness and the concentration of manufacturing activities. The analysis of the moderating effect indicates that environmental regulation and environmental protection expenditures positively moderated the relationship between AI technology and renewable energy development and climate policy uncertainty negatively moderated the relationship between AI technology and renewable energy development. Further analysis revealed that AI technology has the potential to substantially improve the development of local renewable energy resources while also facilitating the advancement of renewable energy in adjacent areas, exhibiting spatial spillover effects. This study verifies the positive effects of AI technology on renewable energy development and enriches existing research perspectives in the field of energy economics. Full article

A new type of transportation vehicle, the maglev car, is gaining attention in the automotive and maglev industries due to its potential to meet personalized urban mobility and future travel needs. To optimize the chassis layout of maglev cars, this paper proposes a compact powertrain integrating electrodynamic suspension with in-wheel motor technology, in which a permanent magnet electrodynamic in-wheel motor (PMEIM) enables integrated propulsion and levitation. First, the PMEIM external magnetic field distribution is characterized by analytical and finite element (FEM) approaches, revealing the magnetic field distortion of the contactless powertrain. Subsequently, the steady-state electromagnetic force is modeled and the operating states of the PMEIM powertrain are calculated and determined. Next, the PMEIM electromagnetic design is conducted, and its electromagnetic structure rationality is verified through magnetic circuit and parametric analysis. Finally, an equivalent prototype is constructed, and the non-contact electromagnetic forces of the PMEIM are measured in bench testing. Results indicate that the PMEIM powertrain performs propulsion and levitation functions, demonstrating 14.2 N propulsion force and 45.8 N levitation force under the rated condition, with a levitation–weight ratio of 2.52, which hold promise as a compact and flexible drivetrain solution for maglev cars. Full article

Compared to traditional marine productivity, marine new-quality productivity (MNQP) is composed of advanced productive forces driven by the deepening application of new technologies, is characterized by the rapid emergence of new industries, new business models, and new modes of operation, and is marked by a substantial increase in total factor productivity in the marine economy. It has, therefore, become a new engine and pathway for China’s development into a maritime power. The main research approaches and conclusions of this paper are as follows: ① Using a combined order relation analysis method–Entropy Weight Method (G1-EWM) weighting method that integrates subjective and objective factors, we measured the development level of China’s MNQP from 2006 to 2021 across two dimensions: “factor structure” and “quality and efficiency”. The findings indicate that China’s MNQP is developing robustly and still holds considerable potential for improvement. ② Utilizing Gaussian Kernel Density Estimation and Spatial Markov Chain analysis to examine the dynamic evolution of China’s MNQP, the study identifies breaking the low-end lock-in of MNQP as crucial for accelerating balanced development. Spatial imbalances in China’s MNQP may exist both at the national level and within the three major marine economic zones. ③ To further examine potential spatial imbalances, Dagum Gini decomposition was employed to assess regional disparities in China’s MNQP. The DER polarization index and EGR polarization index were used to analyze spatial polarization levels, revealing an intensifying spatial imbalance in China’s MNQP. ④ Finally, geographic detectors were employed to identify the factors influencing spatial imbalances in China’s MNQP. Results indicate that these imbalances result from the combined effects of multiple factors, with marine economic development emerging as the core determinant exerting a dominant influence. The core conclusions of this study provide theoretical support and practical evidence for advancing the enhancement of China’s MNQP, thereby contributing to the realization of the goal of building a maritime power. Full article

Agricultural materials frequently undergo fragmentation due to high-stress conditions during processing, storage, and transportation. Throughout these processes, the spatial arrangement and morphology of particles continuously evolve, rendering the breakage behaviour of particle groups particularly complex. Thus, an in-depth understanding of the fracture processes and breakage mechanisms within particle beds holds significant research value. This study systematically investigates the breakage behaviour of rice particle groups under confined compression through an integrated methodology combining experimental testing, X-ray CT imaging, and finite element modelling (FEM) based on the cohesive zone model (CZM). Results demonstrate that, at the granular assembly scale, external loads are transmitted through force chains and progressively attenuate. As compression proceeds, stress disseminates toward peripheral particle regions. At the individual particle level, particle breakage results from the intricate interaction between coordination number (CN) and localized contact stress, with tensile stress playing a predominant role in the fracture process. An increase in coordination number promotes a more uniform stress distribution and inhibits breakage, thereby exhibiting a “protective effect”. These findings provide valuable insights for the design and optimization of grain processing equipment, contributing to a deeper comprehension of particle breakage characteristics. Full article

This paper aims to provide an in-depth and detailed overview of the relationship between language and cognition in Pāli Buddhist texts. These reflections will touch on several fundamental themes, such as the role of signs in structuring cognitive processes and semiosis as a force linked to the proliferation of concepts and percepts, whose organization underlies the constitution of a shared and partly subjective “world”. The paper will engage with linguistics, semiotics, and biosemiotics in order to acquire a vocabulary capable of better understanding the Buddhist reflections on these issues, and, where possible, it will also offer a genealogical inquiry that explains why the theme of language takes on the pivotal role it holds in Pāli Buddhism. Full article

This study investigated the effects of chronic MC-LR exposure (0 μg/L [Control], 1 μg/L [M1], 3 μg/L [M3], 10 μg/L [M10], and 30 μg/L [M30]) on the muscle nutrient composition, meat quality, and muscle proteomic profile of Nile tilapia (Oreochromis niloticus). In the high-dose group (M30), MC-LR exposure compromised the muscle antioxidant status of Nile tilapia, resulting in reduced meat quality, as evidenced by decreased pH value and water-holding capacity, elevated lipid/protein oxidation, and altered texture parameters (shear force and fragmentation index). Proteomic analysis further revealed a downregulation of proteins associated with ribosomes, suggesting an impairment of muscle protein synthesis in the M30 group. Moreover, despite chronic exposure, only low levels of MC-LR accumulated in the muscle tissue, indicating a negligible health risk to consumers. Collectively, these findings offered valuable insights into the impact of environmental MC-LR contamination on fish muscle quality and nutritional value. Full article

Limb amputations are a growing global challenge. Electrically powered prosthetic hands are heavy, expensive, and battery dependent. Body-powered prostheses offer a simpler and lighter alternative; however, existing designs require high body forces to operate, exhibit poor aesthetics, and have limited dexterity. This study aims to present a design of a hydraulically actuated soft bending finger with a simple and scalable manufacturing process. This is then realised into a five-fingered body-powered prosthetic hand that is lightweight, comfortable, and representative of a human hand. The actuator was formed from two silicone materials of different stiffness (Stiff Smooth-Sil 950 and flexible Ecoflex 00-30) and reinforced with double-helix fibres to generate bending under internal hydraulic pressure. A shoulder-mounted hydraulic system has been designed to convert scapular elevation and protraction into actuator pressure. Finite element analysis and physical tests were performed to examine the bending and blocking force performance of the actuators. The physical actuators achieved bending angles up to 230 degrees at 60 kPa and blocking forces of 5.9 N at 100 kPa. The prosthetic system was able to grasp and hold a 320-g water bottle. The results demonstrate a soft actuator design that provides simple and scalable manufacturing and shows how these actuators can be incorporated into a body-powered prosthesis. This study provides a preliminary demonstration of the feasibility of human-powered prosthetics and necessitates continued research. This work makes progress towards an affordable and functional body-powered prosthetic hand that can improve the lives of transradial amputees. Full article

The center of pressure (CoP) is a key biomechanical indicator for assessing balance and fall risk; however, force plates, the gold standard for CoP measurement, are costly and impractical for widespread use. Low-cost alternatives such as inertial units or pressure sensors are limited by drift, sparse sensor coverage, and directional performance imbalances, with previous supervised learning approaches reporting ML-AP NRMSE differences of 3.2–4.7% using 1D time-series models on sparse sensor arrays. Therefore, we propose a tactile sensor-based CoP estimation system using deep learning models that can extract 2D spatial features from each pressure distribution image with CNN/ResNet encoders followed by a Bi-LSTM for temporal patterns. Using data from 23 healthy adults performing four balance protocols, we compared ResNet-Bi-LSTM and CNN-Bi-LSTM with baseline CNN-LSTM and Bi-LSTM models used in previous studies. Model performance was validated using leave-one-out cross-validation (LOOCV) and evaluated with RMSE, NRMSE, and R². The ResNet-Bi-LSTM with angular features achieved the best performance, with RMSE values of 18.63 ± 4.57 mm in the mediolateral (ML) direction and 17.65 ± 3.48 mm in the anteroposterior (AP) direction, while reducing the ML/AP NRMSE difference to 1.3% compared to 3.2–4.7% in previous studies. Under dynamic protocols, ResNet-Bi-LSTM maintained the lowest RMSE across models. These findings suggest that tactile sensor-based systems may provide a cost-effective alternative to force plates and hold potential for applications in gait analysis and real-time balance monitoring. Future work will validate clinical applicability in patient populations and explore real-time implementation. Full article

Background: Oxazolidinone derivatives are a novel class of synthetic antibacterial agents, characterized by a five-membered heterocyclic ring containing oxygen and nitrogen and a carbonyl functionality at position 2. This pharmacophore is responsible not only for antibacterial activity but also for a variety of other biological activities, including anticancer activity, anticoagulant activity, and several others. A series of novel oxazolidinone derivatives containing a hydroxamic acid moiety were synthesized in our laboratories and identified as potent inhibitors of the enzyme 5-lipoxygenase (5-LO), a key enzyme involved in the biosynthesis of leukotrienes (LTs). LTs are proinflammatory mediators implicated in allergic and inflammatory diseases. Currently, zileuton is the only FDA-approved 5-LO inhibitor, emphasizing the need to develop new agents for the treatment of such diseases. This project aims to develop validated stability-indicating analytical methods for the four most potent novel 5-(hydroxamic acid)methyl oxazolidinone derivatives (PH-211, PH-247, PH-249, and PH-251). Methods: The compounds were analyzed using Waters Acquity Ultra-High-Performance Liquid Chromatography (UHPLC-UV) with an ultraviolet detector to determine their stability in human plasma and under various forced degradation conditions, including acidic, basic, oxidative, and thermal conditions. Liquid chromatography–quadrupole time-of-flight mass spectrometry (LC-QToF-MS) was used to identify possible degradation products. Results: The compounds were found to be stable in human plasma and under thermal degradation conditions with high extraction recoveries (82–90%) but unstable in acidic, basic, and oxidative conditions. Conclusions: The findings show that the compounds are stable in biological conditions; they hold promise for the treatment of inflammatory and allergic diseases. Full article

As the digital economy increasingly integrates with the real economy, the goal of high-quality economic development in China has become increasingly clear. Promoting high-quality regional economic development through the integration of the digital and real economies holds significant practical importance for achieving Chinese modernization. This study selects panel data from 2013 to 2023 for 31 provinces, autonomous regions, and municipalities directly under the central government in China. It employs the entropy method to measure the development levels of both the digital and real economies in each province. It uses a coupling coordination degree model to gauge their level of integration. By constructing bidirectional fixed-effects models, mediating effect models, and spatial econometric models, this study explores the impact of Digital–real Integration (DRI) on regional High-Quality Development (HQD). The findings reveal that DRI promotes high-quality regional economic development, with a 1% increase in DRI leading to a 4.810% increase in high-quality regional economic development. Meanwhile, this effect exhibits significant regional disparities. During this process, industrial structure upgrading and scientific and technological innovation serve as mediating factors, with coefficients of 1.249 and 10.562, respectively, for every 1% increase in DRI. Moreover, DRI exhibits significant spatial spillover effects, benefiting neighboring regions. Based on these findings, the paper proposes targeted recommendations, including strengthening digital infrastructure to lay a solid foundation for integrated development, implementing an innovation-driven strategy to master core technologies, optimizing production factor allocation to amplify DRI’s driving force, breaking regional economic barriers, and adopting dynamic, differentiated development strategies tailored to local conditions. These measures aim to fully harness DRI’s potential in advancing high-quality regional economic growth, offering empirical insights for coordinated regional development. Full article

Green innovation holds significant importance for achieving sustainable development goals. Artificial intelligence has emerged as the primary force behind a new wave of technological and industrial transformation. Using data on Chinese A-share listed manufacturing firms from 2012 to 2023, this study examines the influence of AI policy on corporate green innovation. A chain mediation model is used to identify and test the specific pathway through which this influence operates. The results reveal three findings: First, AI policy has a significantly positive influence on corporate green innovation. Second, industrial agglomeration and knowledge diversity serve as chain mediators, playing the role of transmitting the effect of AI policy to corporate green innovation. Third, AI policy more effectively stimulates green innovation in specific contexts, particularly among SMEs, non-SOEs, high-tech industries, and competitive sectors. This study deepens our understanding of how AI policy can promote corporate green innovation, providing important insights for advancing the coordinated development of green and intelligent manufacturing. Full article