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Based on clarifying the structural difference between jade fibre and general polyester fibre, this paper aims to study the dyeing properties and dyeing adsorption mechanism of jade fibre with disperse dye and cationic dye.

The chemical structure and microstructure of jade fibre were briefly explained comparing with ordinary polyester fibre. The dyeing rate curve and dyeing adsorption isotherm of disperse dyes and cationic dyes on jade fibre were, respectively, studied. The dyeing uptake, dyeing absorption mechanism, and the main dyeing process parameters were proposed.

Jade fibre can be dyed with cationic dye and disperse dye. The suitable exhaust dyeing process is 110°C and 40 minutes for disperse dye, 100°C and 60 minutes for cationic dye. The dyeing uptake on jade fibre with both disperse dyes or cationic dyes is much higher than that on general polyester fibre and acrylic fibre, and the dyeing adsorption mechanism belongs to the combination of Langmuir and Nernst adsorption for disperse dyes and Langmuir adsorption for cationic dyes. Comparing with ordinary polyester fibre, jade fibre has the advantage of low temperature dyeing and reduced effluent, as is significant to energy-saving and emission reduction.

Jade fibre is a new type of modified polyester fibre with the function of health protection and energy conservation. There are little technical data in the literature at present about the dyeing property of jade fibre.

The purpose of this paper is to synthesise a novel wet-rubbing fastness improver with diphenylmethane diisocyanate (MDI), polyethylene glycol (PEG), dimethylol propionic acid (DMPA), diethylenetriamine and epichlorohydrin.

The synthetic reaction was carried out through three steps: pre-polymerising, chain-extending and chemically modifying. The influence of monomers dosage and ratio, temperature and time on reaction system and wet-rubbing fastness of reactive dye is studied. The target product was characterised by transform infrared spectroscopy analysis.

The optimum synthetic process condition of the improver is as follows: reaction temperature 100°C; pre-polymering time 2.5 hours with R value [n(NCO): n(OH)] 1.35 and DMPA 7 per cent (on percentage of total moles of MDI and PEG); chain-extending time 30 minutes with diethylenetriamine 1.5 per cent (on percentage of total moles of MDI and PEG); modifying time 2 hours with diethylenetriamine : epichlorohydrin = 1:2 (mole ratio).

The synthetic product is a three-functions-in-one (filming, salt-forming and cross-linking) wet-rubbing fastness improver which can obviously improve the wet-rubbing fastness of reactive dyes from Grade 2-3 to Grade 4.

The wet-rubbing fastness improver is novel and could find numerous applications in dyeing and finishing.

This paper aims to synthesise a novel crosslinker (crosslinker triethylthiosulphate (TETS)) which contains three Bunte groups in its molecule. The crosslinker is able to react with the hydroxyl groups in cellulosic fibres and the amino group in protein fibres so that it may find applications in many fields.

Crosslinker TETS was synthesised under constant reflux. Capillary electrophoresis analysis and Raman analysis were used to follow the synthetic reaction and characterise the product. The crosslinking between TETS and cellulose could be confirmed by infrared analysis and elemental analysis.

Crosslinker TETS 2,2′,2″‐nitrilo‐TETS was synthesised with a yield of 71.3 per cent. The synthetic reaction follows the mechanism of first, aziridine‐forming and then cyclo‐opening by nucleophiles. A new low‐cost purifying method using ethanol at different temperatures with good yield was proposed.

Practical applications of crosslinker TETS could be studied further.

Crosslinker TETS may find its use in durable‐press finish of cotton fabric, cellulosic fibre modifying to improve dyeing properties and increase fixation of reactive dyes, wet strength improvement of Kraft paper, anti‐fibrillating finish of Lyocell fibre, etc.

A novel polyfunctional crosslinker which belongs to a new Bunte salt was created. The structure, the synthetic reaction, the separation method and the crosslinking reaction of crosslinker TETS have not been reported before.

The purpose of this paper was to study the dyeing properties of polysulphonamide (PSA)/aramid 1313 (MPIA) blended yarn by selecting suitable dyes and carriers required in the dyeing process.

Dyeing the blended yarn with cationic dyes, acid dyes, disperse dyes, reactive dyes and pigment, and comparing the shades, K/S values and fastness of the blended yarns.

The PSA/MPIA blended fibre is suitable for dyeing with the cationic dye at high temperature and pressure in the presence of carrier acetophenone, and good homochromatism is seen on the two fibres when using same type of dye.

PSA fibre is a thermo-resistant and flame-retardant product made in China in recent years. Blended with aramid 1313 fibre, it may acquire good spinnability. But there is little technical report about properties of the blended yarn in the literature at present. This paper reports the dyeing property of such fibres for the first time.

This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

Smart cities show a “booming” trend both in the academia and the industry in recent years. Scholars across the world have been investigating how new technologies are applied to develop new services to the inhabitants and cities all over the world also address the “smart cities” challenges by promoting policymaking and governance. This paper aims to conduct in-depth research on smart cities by combining the study of governance policy study and information technology study.

This paper empirically mapped the trends of smart city development, outstanding scholars and hot topics about smart cities by analyzing important references using CiteSpace. The authors visualized references and topics to analyze smart city research, based on empirical data from Web of Science. Furthermore, two most important research branches – topics from smart city governance research and those from information systems (IS) research were studied, respectively.

First, the authors mapped the development of research and divided the development into three different stages. Second, the authors explored important, influential and instructive publications and publications’ attributes including authors, institutions, journals and topics. Third, the authors found there are different characteristics between the IS group and the governance group in publication situations, influential institutions, journals and authors, although the research points of the two branches are overlapping and fragmented. Finally, the authors proposed important topics, which include “internet of things (IoT)”, “big data”, “smart city systems” and “smart city management” and the authors predicted that “IoT” and “smart city challenge” would be future trends in recent years.

This study is an innovative research of its category because it visualized the development of smart city research, analyzed both governance and technology branches of smart city research synthetically using CiteSpace and forecasted future trends of smart city research by topics analysis and visualization of evolution.