Transient thermocapillary convection flows near a suddenly heated vertical wire are widely present in nature and industrial systems. The current study investigates the dynamical evolution and heat transfer for these transient flows near a suddenly heated vertical wire, employing scaling analysis and axisymmetric numerical simulation methodologies. Scaling analysis indicates that there exist four possible scenarios of the dynamical evolution and heat transfer for these transient flows, dependent on the wire curvature, Marangoni number and Prandtl number. In a typical scenario of the dynamical evolution and heat transfer, heat is first conducted into the fluid after sudden heating, resulting in an annular vertical thermal boundary layer around the wire. The radial temperature gradient may generate a thermocapillary force on the liquid surface, dragging the liquid away from the wire. The pressure gradient also drives a vertical flow along the wire. Further, the current study analyses and derives the scaling laws of the velocity, thickness and Nusselt number for the surface and vertical flows in different scenarios. Additionally, a number of two-dimensional axisymmetric numerical simulations are performed. The flow structure around the suddenly heated vertical wire is characterised under different regimes and the validation for the proposed scaling laws in comparison with numerical results is presented.

We study the temperature–velocity (TV) relation for laminar adiabatic and diabatic hypersonic boundary layers. By applying an asymptotic expansion to the compressible boundary-layer temperature equation, we derive a first-order equation for the TV relation, where the zeroth-order solution is found to be the classical Crocco–Busemann quadratic relation. The ensuing relation predicts accurately the temperature profile by using the velocity for hypersonic boundary layers with Chapman, power and Sutherland viscosity laws, arbitrary heat capacity ratios, variable Prandtl numbers close to unity and Mach number of up to 10. The Mach-number- and wall-temperature-independent quantities in our relation are also investigated. The present relation has the potential to function as a temperature wall model for laminar hypersonic boundary layers, especially for cold-wall cases.

Magnetite-enriched mining tailings are a cost-effective and abundant catalytic material with inherent magnetic recyclability. Yet their practical application in catalysis is often constrained by their limited surface area and sluggish reaction kinetics. To address these issues, we developed a facile one-step co-precipitation method to synthesize a magnetic nano-Fe3O4 (MNP) catalyst that exhibits enhanced surface reactivity for efficient activation of H2O2 towards tetracycline (TC) degradation. The system achieved complete (100%) removal of TC at an initial concentration of 20 mg L–1 within 90 min and demonstrated robust catalytic performance across weakly acidic to neutral pH conditions. Mechanistic investigations confirmed that ⋅OH is the primary reactive oxygen species involved, with ⋅O2⁻ and 1O2 providing supplementary contributions to the degradation. Remarkably, the intrinsic magnetic properties ensured efficient MNP catalyst recovery. This work provides a sustainable and scalable wastewater treatment strategy, leveraging mining tailings as a cost-effective resource to treat wastewater while also providing economic and environmental benefits.

Grasp detection is a significant research direction in the field of robotics. Traditional analysis methods typically require prior knowledge of the object parameters, limiting grasp detection to structured environments and resulting in suboptimal performance. In recent years, the generative convolutional neural network (GCNN) has gained increasing attention, but they suffer from issues such as insufficient feature extraction capabilities and redundant noise. Therefore, we proposed an improved method for the GCNN, aimed at enabling fast and accurate grasp detection. First, a two-dimensional (2D) Gaussian kernel was introduced to re-encode grasp quality to address the issue of false positives in grasp rectangular metrics, emphasizing high-quality grasp poses near the central point. Additionally, to address the insufficient feature extraction capabilities of the shallow network, a receptive field module was added at the neck to enhance the network’s ability to extract distinctive features. Furthermore, the rich feature information in the decoding phase often contains redundant noise. To address this, we introduced a global-local feature fusion module to suppress noise and enhance features, enabling the model to focus more on target information. Finally, relevant evaluation experiments were conducted on public grasping datasets, including Cornell, Jacquard, and GraspNet-1 Billion, as well as in real-world robotic grasping scenarios. All results showed that the proposed method performs excellently in both prediction accuracy and inference speed and is practically feasible for robotic grasping.

Drawing on semi-structured interviews with 36 policymakers, experts and scholars, this paper employs a principal-agent framework to analyse China’s carbon market governance. The findings reveal that institutional misalignment between central and local priorities undermines market efficacy. While mechanisms like the Target Responsibility System (TRS) and environmental inspections aim to enforce compliance, fragmented incentives and passive central supervision exacerbate policy incoherence. Owing to competing mandates, local governments prioritize short-term GDP growth over the development of the carbon market, thereby relegating emissions trading to a peripheral status. State-owned enterprises (SOEs) dominate market participation, fulfilling compliance through political alignment but distorting price signals and marginalizing private actors. China’s hybrid governance model, which combines top-down controls with decentralized experimentation, generates systemic contradictions where weak enforcement, ritualistic compliance and data opacity persist as the dominance of SOEs colludes with local developmentalism to weaken carbon pricing. Overall, carbon market governance mechanisms have paradoxically incentivized regulated entities to prioritize developmental goals over improving carbon market infrastructure.

With the eastward expansion of the Western Zhou c. 1050 BC, the Jiaodong Peninsula on the north-east coast of modern-day China became part of a large polity. Excavations at Qianzhongzitou, located on this peninsula, are revealing how political control over local populations took place. Here, the authors focus on a sequence of Zhou-period, non-residential platforms, the construction of which signifies new forms of ritual spaces. These types of spaces, also found elsewhere in the region, arguably aided in the state assimilation of local deities, illustrating the critical role that ritual played in political unification of early Chinese states and dynasties.