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This paper aims to establish a photoacoustic detection system for SO₂ using UV-LED and testify its feasibility for sensitive measurement. The work in this paper can avoid potential crossover interference in infrared (IR) range and also balance the capability and cost of feasible excitation for photoacoustic detection system.

In this experimental work, a cantilever-enhanced–based photoacoustic SO₂ detection system using an ultraviolet (UV) LED light source with a light power of 4 mW as the excitation was established.

A feasible photoacoustic detection system for SO₂ using UV-LED was established. Experimental results demonstrate that the detection limit of the system can reach the level of 0.667 ppm, which can serve as a reference for the application of PAS in insulation fault diagnosis.

This work investigated the potential of using ultraviolet photoacoustic spectroscopy to detect trace SO₂, which provided an ideal replacement of infrared-laser-based detection system. In this paper, a photoacoustic detection system using LED with a low light power was established. Low light power requirement can expand the options of light sources accordingly. In this paper, the absorption characteristics of SO₂ in the presented detection system and ultraviolet range were studied. And the detection limit of the presented system was given. Both of which can provide reference to SO₂ detection in ambient SF₆.

This paper aims to study the tribological properties of high strength glass fabric/phenolic laminate composites reinforced by carbon fiber (CF) with and without graphene oxide (GO) modified.

In this study, the tribological performance tests of the composites were conducted on a block-on-ring tester (MRH-03). The applied load, linear velocity and duration of time are 200 N, 0.5 m/s and 120 min, respectively. The friction coefficient and specific wear rate were shown.

The optimal content of GO on CFs is 0.2 per cent mass fraction. The optimal content of GO addition means the strongest interfacial adhesion between the CF and the matrix.

The main originality of this paper is to reveal the effect of surface GO on CF on the tribological properties of fabric-reinforced composites.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2019-0273/

A conveyor device is studied with the aim to reduce the friction between the inner surface of the beam and the chain. The lower is the friction between the chain and the beam, the lower is the surface wear. The magnetic repulsion force among permanent magnets (PMs) placed on the beam and on the chain is utilized to reduce friction. The paper aims to discuss these issues.

The considered magnetic suspension is realized with PMs in repulsive configuration; it is designed by solving a constrained optimization problem, with reference to the geometry of the 90° horizontal bend FlexLink WL322 conveyor. Flux density field and its gradient are evaluated using volume integral equation method, allowing to calculate the forces acting on the chain and the stiffness of the magnetic suspension.

The magnetic suspension prototype was manufactured and tested. The experimental and calculated values of the forces acting on the chain compares well. A stable horizontal equilibrium of the chain was obtained during both static and dynamical tests.

The quasi-static model used neglects the dynamical interactions among the elements of the chain, the PMs and loads weight during motions and the eddy current losses in the aluminium beam. However the dynamical tests on the prototype show that the chain motion is regular up to the nominal velocity all along the conveyor with the exception of the trailing edge of the 90° curve.

The tests on the prototype show the possibility of a removal or at least a reduction of the friction force between the chain and the inner side of the beam by means of a passive magnetic suspension. As a consequence a reduction of noise and vibrations and an increase of the mean-time-to-failure is expected.

Prototype testing shows that the unavoidable vertical instability of the magnetic forces has no practical consequence since, reducing the allowed vertical gap, the chain is stabilized by the gravitational force.

The purpose of this paper is to investigate the influence of four components of social capital on farmers’ participative behaviour in collective actions for constructing and operating small-scale groundwater irrigation systems on the Guanzhong Plain, Shaanxi Province, China.

The four components (social networks, social trust, social reciprocity and social participation) were derived by employing exploratory factor analysis. Logistic model was used to estimate the influence of these components on farmers’ participative behaviour. Information was obtained from a field survey covering six counties in 2011 of Shaanxi Province, China.

The findings indicate that considering different components of social capital allows for a better understanding of farmers’ participative behaviour. The authors find that higher levels of social trust and social participation lead to a higher propensity for collective action, while social reciprocity reduces the probability of participation. Other socio-economic factors and farming characteristics such as education levels, cultivated area, cropping patterns and grain subsidies also have a significant impact.

The findings suggest creating favourable conditions for communication and information exchanges between households, which enhance their trust of each other, and encourage farmers to participate in collective affairs. Moreover, supportive rules are necessary for the future development of collective action. The results of this study also have implications for national irrigation plans for small-scale irrigation facilities in other developing countries.

A consideration of the different components of social capital allows for a more precise understanding of farmers’ participative behaviour.

The purpose of the paper is to make a high speed motor based on the characteristics of high strength silicon steel. With the higher requirements for torque density and power density of the driving system of electric vehicles (EV), conventional magnetic materials have been difficult to meet the demands in the future. In this paper, a new type of high-strength non-grain-oriented (NGO)material is tested.

Through analyzing the characteristic of high strength silicon steel, it is applied to the rotor part of a high-speed motor. A topological optimization is applied to achieve higher power density and higher efficiency of the motor.

The feasibility of the scheme was analyzed by the finite element method, and a prototype was also fabricated to verify the analysis.

In this paper, the characteristics of new soft magnetic materials as a breakthrough to manufacture a new generation of high-performance electrical machine (EM) are discussed. Consequently, the presented work greatly facilitates further explorations and guides the innovative application of soft magnetic materials and the iterative optimization of motor structure.

This paper aims to explore various tensions related to the diffusion and reception of the New Qing History (NQH) in China, and more specifically, it aims at underlying a recurrent tension within the core of this debate, between a Global and a Nationalist historical narrative.

The author’s focus is to analyze various texts published in China between 2006 and 2018.

The author argues that the intensity of the current debate is partly related on the one hand, to the fact that NQH undermines various aspects of China’s Nationalist teleology and territorial claims and, on the other hand, to the basic difficulty of accepting the coexistence of various historical representations that are risking to weaken contemporary’s justifications of its rising schemes.

The text presents an original reading of some important issues raised by the NQH debate.