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The purpose of this paper is to investigate the effects of coupling agents on the structure and properties of the nanocomposite films and clarify their mechanism. Polyimide (PI)/Al₂O₃ nanocomposite films were prepared using different coupling agents.

Poly(amic acid) (PAA) was firstly synthesised from appropriate pyromellitic diannanocomposite and oxydianiline in N‐dimethylacetamide. Calculated amount of nano‐Al₂O₃ particles modified by different coupling agents (KH550, KH560, KH570 and AE3012) were added to PAA solution by an ultrasonic‐mechanical method and PI/nano‐Al₂O₃ film was fabricated by heat curing. The microstructure, thermal stability, mechanical properties and electric breakdown strength of the films were characterised.

The addition of coupling agents could greatly improve the dispersion homogeneity of Al₂O₃ nano‐particles in PI matrix. Results of corresponding characterisations indicated that both the thermal stability and mechanical properties of PI/Al₂O₃ nanocomposite film with KH550 were greater/better than others, while AE3012 could improve the electric breakdown strength.

In the present discussion, the effects of different coupling agents, KH550, KH560, KH570 and AE3012, were investigated. Results of this research work would be beneficial to an in‐depth understanding on the relationship between microstructure and properties of PI composites, and further promote the development of the high‐performance PI insulating materials.

The four coupling agents, KH550, KH560, KH570 and AE3012, were firstly used to disperse the nano‐Al₂O₃ particles in PI matrix. The effects of coupling agents on microstructure and properties of composites were discussed by the authors in detail.

The purpose of this paper is to study the influence of different carbon chain lengths in coupling agents on the water resistance and compatibility of modified long afterglow phosphors and attempt to obtain their modification model and mechanism.

Three saturated-fatty-acid (caprylic, lauric, stearic acid)-based Al-Zr CAs (coupling agent) was synthesised and applied to modify the long afterglow phosphors SrMgAl₄O₈:Eu₂₊,Dy₃₊.

Results show that the coated amount on phosphors decreased from 13.41 to 6.53 per cent with the increased carbon chain length of fatty acid, and the better water resistant and suitability with organic resin can be obtained by lauric-based Al-Zr CA.

Considering that the decomposition process of modified phosphor was related with the decomposition performance of corresponding coupling agents and original phosphor, a method was first proposed to calculate the coated amount on phosphors by thermogravimetric analyser parameters.

Over the past ten years, there has been continuing development of coupling agent technology and the utilisation of these materials in treating reinforcing fibres in composite manufacture. This paper reviews these developments and examines both the chemistry and the methods used in analysing the surfaces and interfaces of glass reinforced laminates, with special emphasis on how these areas affect the performance of printed circuit boards.

Zircoaluminate metallo organics constitute a unique family of surface modification agents which are cost effective in irreversibly modifying all inorganic fillers/pigments, carbon black, and many organic pigments. Direct in situ addition to coating resin or solvent (at 0.5–1.5 phf) will result in pronounced viscosity reduction (50.95%), reduced settling and particulate agglomeration, and improved colour strength and opacity. Zircoaluminates also improve salt spray resistance, enhance adhesion to metal substrates and eliminate telegraphing.

To prepare a new type of composite for selective laser sintering 3D printing, the surface of Al₂O₃ nanoparticles was modified by the coupling agent (3-methacryloxypropyl)-trimethoxy silane (KH570) before coated with thermoplastic epoxy resin (TER).

Laser diffraction confirmed that the size distribution of prepared powder materials in this study ranged between 20 to 80 µm. Thermogravimetric analysis (TGA) showed that the loading of organic matter was below 5 per cent. Fourier transform infrared spectroscopy indicated that the silane coupling agent molecule bound strongly with the alumina. X-ray diffraction confirmed the prepared powder materials to be α-alumina. Through the angle of repose (AOR) test, the AOR = 18.435º was obtained, suggesting the high flowability of prepared powder materials. Scanning electron microscopy (SEM) observation demonstrated that the shape of the prepared powder materials was sphere-like grains.

Molding properties of prepared powder materials were studied on the basis of particle size distribution, particle size, sphericity, crystal structure and the reaction mode of the TER. This prepared powder materials can be well applied to the production of epoxy resin-coated Al₂O₃ composite parts with high precision and good mechanical performance.

This composite can be well applied to the production of epoxy resin-coated Al₂O₃ composite parts with high precision and good mechanical performance.

A recommendation system for an extended process of information retrieval in distributed information systems is proposed. This system is both a model of dynamic cognitive categorization processes and powerful real application useful for knowledge management. It utilizes an extension of fuzzy sets named evidence sets as the mathematical mechanisms to implement the categorization processes. It is a development of some aspects of Pask’s conversation theory. It is also an instance of the notion of linguistic‐based selected self‐organization here described, and as such it instantiates an open‐ended semiosis between distributed information systems and the communities of users they interact with. This means that the knowledge stored in distributed information resources adapts to the evolving semantic expectations of their users as these select the information they desire in conversation with the information resources. This way, this recommendation system establishes a mechanism for user‐driven knowledge self‐organization.

To present an account of cognition integrating second‐order cybernetics (SOC) together with enactive perception and dynamic systems theory.

The paper presents a brief critique of classical models of cognition then outlines how integration of SOC, enactive perception and dynamic systems theory can overcome some weaknesses of the classical paradigm.

Presents the critique of evolutionary robotics showing how the issues of teleology and autonomy are left unresolved by this paradigm although their solution fits within the proposed framework.

The paper highlights the importance of genuine autonomy in the development of artificial cognitive systems. It sets out a framework within which the robotic research of cognitive systems could succeed.

There are no immediate practical implications but see research implications.

It joins the discussion on the fundamental nature of cognitive systems and emphasise the importance of autonomy and embodiment.

The purpose of this paper is to argue that active citizenship and organisational transparency are necessary to increase stakeholders' influence in policy processes. Active citizenship is necessary to involve stakeholders in policy processes and organisational transparency is necessary to improve communications between them and policy makers.

First, this paper explains a conceptual framework to understand communications in social systems. Second, it illustrates its application with reference to concrete policies in England.

It is found that for active citizenship it is necessary not only to increase stakeholders' competencies but also make effective those organisational structures relevant to the policy issues of concern. However, and this is a key reason to increase people's competencies, these structures are the outcome of self‐organising processes shaped by those who are better organised, with more resources and in positions of power.

Beyond informed and well‐grounded dialogues, communications between citizens and policy makers happen through organisation structures that activate some resources at the expense of others and involve some stakeholders at the expense of others. Unless these structures make possible balanced communications between them, citizens will find it difficult to influence policy makers.

The paper sees the policy for active citizenship and community empowerment in England under the lens of a cybernetic framework.

Stereolithography is a well-established technique for producing complex part for rapid prototyping purpose by using UV or laser as a source for curing process. This technique has been implemented in a lot of industrial sectors. However, the parts fabricated by this technique exhibit low mechanical and thermal properties hindering a fast-growing application. The purpose of this paper is to propose a new method of digital light rapid prototyping (DLRP) system and investigate the effect of the addition of bamboo fiber with surface modification on improvement of mechanical properties of urethane diacrylate/bamboo composite.

Test specimens were fabricated using aliphatic urethane diacrylate photopolymer as matrix material and bamboo fiber as reinforce material. Adhesion between matrix and reinforce materials is a big issue in compositing, especially when handling bamboo as hydrophilic material and urethane diacrylate as hydrophobic material. To overcome this problem, two surface modifications of bamboo fiber, alkali treatment and silane treatment, were implemented.

As a result, bamboo fiber can increase mechanical properties of urethane diacrylate photopolymer fabricated by rapid prototyping system.

In this paper, the authors investigate the effect of the addition of bamboo powder with surface modification on mechanical properties. Test specimens were fabricated using aliphatic urethane diacrylate photopolymer as matrix material and bamboo powder as reinforce material.

The purpose of this paper is to study the dynamical group consensus of heterogeneous multi-agent systems with fixed topologies.

The tool used in this paper to model the topologies of multi-agent systems is algebraic graph theory. The matrix theory and stability theory are applied to research the group consensus of heterogeneous multi-agent systems with fixed topologies. The Laplace transform and Routh criterion are utilized to analyze the convergence properties of heterogeneous multi-agent systems.

It is discovered that the dynamical group consensus for heterogeneous multi-agent systems with first-order and second-order agents can be achieved under the reasonable hypothesizes. The group consensus condition is only relied on the nonzero eigenvalues of the graph Laplacian matrix.

The novelty of this paper is to investigate the dynamical group consensus of heterogeneous multi-agent systems with first-order and second-order agents and fixed topologies and obtain a sufficient group consensus condition.