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Nomex fabric is irradiated by an Xe₂ ^* excimer UV lamp (172 nm). The influence of different irradiating times and atmospheres (nitrogen and air) on the properties of Nomex fabric has been studied. The results show that the wettability of Nomex fabrics greatly improves when irradiated for 2 minutes. The scanning electron microscope (SEM) photos denote that the surface of the irradiated Nomex fiber is etched and the degree of etching in nitrogen is more severe than that in air. The XPS measurement proves that the surface of the Nomex fibers, which is irradiated in nitrogen and in air, generates carboxyl and hydroxyl groups. The results also show that the adhesive strength of the Nomex/polyethylene composite is reinforced by the irradiation.

A novel technology for the interconnection of bare chips in power modules is presented which circumvents the drawbacks of multiple heavy‐wire bonding as well as of reflow soldering of many single copper clips inserted into solder preforms. A piece of structured copper‐clad polyimide foil, here called a foil‐clip, is used to provide all required connections, i.e., die‐to‐die and die‐to‐substrate. Hot‐bar soldering or glueing is used for the final joining after adjustment of the foil‐clip to its land areas. Depending on the complexity of the module only a few touch‐downs of the heated tool are required for full assembly. In contrast to the well‐known TAB technique, in foil‐clip technology a copper layer is the top layer (typical thickness: 60 µm). The polyimide (PI) foil (e.g., 25 µm) is used simultaneously as insulation and solder stop layer on the die side. The contact of the photo‐lithographically patterned copper layer with the pads on top of the die and the substrate is achieved by grooving holes into the PI layer which are then filled in a subsequent step with solder or screen‐printed conductive adhesive. Via‐hole formation is achieved by light‐induced ablation. In the first stage of process development a scanning line beam of a pulsed UV excimer laser is moved across the surface of a metal mask containing the pattern to be eroded in the polyimide layer. The present paper describes the optimisation of process parameters in terms of wavelength, pulse rate and fluence variation as well as speed of the substrate displacement during illumination. In future, the use of a novel UV excimer lamp is envisaged which enables large‐area exposure and selective photoetching by using contact metal masks. Furthermore, measurements of the current load capability of the copper interconnects produced by foil‐clips are presented. With an infrared imaging system, the hot‐spot temperature was determined for increasing load current on tracks of different widths and lengths on their way down from high current rectifier diodes to DCB‐module substrates. It is shown that tracks with many squares (N = length/width => ∞) can be loaded with at least I = 22 A. On the other hand, due to cooling through the solder joints, the shortest tracks (N = 1) carry up to 128 A.

Dielectric barrier discharge (DBD) is widely used in the treatment of skin disease, surface modification of material and other fields of electronics. The purpose of this paper is to design a high-performance power supply with a compact structure for excimer lamps in electronics application.

To design a high-performance power supply with a compact structure remains a challenge for excimer lamps in electronics application, a current-source type power supply in a single stage with power factor correction (PFC) is proposed. It consists of an excitation voltage generation unit and a PFC unit. By planning the modes of the excitation voltage generation unit, a bipolar pulse excitation voltage with a high rising and falling rate is generated. And a high power factor (PF) on the AC side is achieved by the interaction of a non-controlled rectifier and two inductors.

The experimental results show that not only a high-frequency and high-voltage bipolar pulse excitation voltage with a high average rising and falling rate (7.51GV/s) is generated, but also a high PF (0.992) and a low total harmonic distortion (5.54%) is obtained. Besides, the soft-switching of all power switches is realized. Compared with the sinusoidal excitation power supply and the current-source power supply, the proposed power supply in this paper can take advantage of the potential of excimer lamps.

A new high-performance power supply with a compact structure for DBD type excimer lamps is proposed. The proposed power supply can work stably in a wide range of frequencies, and the smooth regulation of the discharge power of the excimer lamp can be achieved by changing the switching frequency. The ideal excitation can be generated, and the soft switching can be realized. These features make this power supply a key player in the outstanding performance of the DBD excimer lamps application.

How to use a simple and classical topology to provide a high-efficiency excitation voltage for dielectric barrier discharge (DBD) loads is one of the primary problems to be solved for DBD application fields.

To address the issue, a set of modes that can generate a high-efficiency pulse excitation voltage in a full-bridge inverter are adopted. With the set of modes, the unique equivalent circuit of DBD loads and the parasitic parameter of the step-up transformer can be fully used. Based on the set of modes, a control strategy for the full-bridge inverter is designed. To test the performance of the power supply, a simulation model is established and an experimental prototype is made with a DBD excimer lamp.

The simulation and experimental results show that not only a high-efficiency excitation voltage can be generated for the DBD load, but also the soft switching of all power switch is realized. Besides this, with the set of modes and the proposed control strategy, the inverter can operate in a high frequency. Compared with other types of power supplies, the power supply used in the paper can fully take advantage of the potential of the excimer lamp at the same input power.

This work considers that how to use a simple and classical topology to provide a high-efficiency excitation voltage for DBD loads is one of the primary problems to be solved for DBD application fields.

The purpose of this paper is to provide a review of recent developments in electromagnetic radiation (EMR) sensing.

Following a short introduction, this paper discusses a selection of recent research and development activities concerning the sensing of gamma radiation, X‐rays and ultraviolet (UV) radiation.

This shows that novel sensors are being developed for all of these classes of EMR. Improved gamma sensors are attracting strong interest in the USA, reflecting concerns regarding nuclear security. Novel X‐ray and UV sensors are often being developed in response to new and emerging uses of these types of radiation.

This paper provides a technical review of recent research into sensors for detecting gamma radiation, X‐rays and UV radiation.

The present research aims to manage the formulations of pigment-based inks containing aminopropyl/vinyl/silsesquioxane (APSV) as a pigment binding agent for inkjet printing of polyester as a commercial trial for the printing of polyester as a single-step process.

The proposed formulations incorporated APSV by using the mini-emulsion technique at a low relieving temperature under the thermal initiation or UV radiation of vinyl-terminated groups in APSV. In this study, the storage stability of inks with regard to physical properties was broadly examined. Moreover, the color performance, including colorimetric data, color fixation and fastness properties of printed fabrics was evaluated.

The results indicated that the inks containing APSV were formulated and were stable in terms of particle size, dispersion stability, surface tension and viscosity over a period of one month and for four freeze/thaw cycles. APSV successfully fixed the pigment-based inkjet inks on polyester fabric and could achieve a significantly higher color performance and degree of fixation than the formulated inks without APSV.

It could also fulfill all the physical properties of ink prerequisites over storing and eliminating all challenges in improving the performance and utilization of inkjet printing.

APSV can also be used as a pigment binding agent to formulate inks for inkjet printing of polyester fabrics as the authors’ past examination for inkjet printing of polyester fabrics post-treated with APSV.

This study eliminates the noteworthy challenges in formulating the pigment-based inks for textile applications by incorporation of a binder while keeping up the necessary viscosity profile for a specific print head.

This study addressed all the issues arising from the complex nature and very challenging requirements of inkjet inks.

The purpose of this paper is to prepare ultra-violet (UV)-curable inkjet inks for textile printing application. The influence of both type and component ratio of monomer/oligomer on the quality of the desired viscosity range is studied. Moreover, the effect of pigment/resin ratio on the rheological behaviour of the ink has been studied.

Aqueous dispersions of nanoscale organic pigments were prepared through ball milling and ultrasonication. The dispersed pigments were encapsulated into UV-curable resin via miniemulsion technique, using different types and component ratios of monomers and oligomers.

It was found that the monomer/oligomer ratio of 2:3 and the pigment/resin ratio of 2:1 gave the most stable miniemulsion dispersions and provided the most suitable rheological range for inkjet printing inks.

As the rheology of the ink is optimised, most of the problems associated with the jetting process could be avoided.

This method of using UV-curable encapsulated inks eliminates the usage of binders, which are the principal factor for nozzle clogging of the print head. In addition, binders are responsible for the coarse handle of the printed textiles.

The UV-curable inks were viewed as a green technology by the US Environmental Protection Agency.

This method is simple and fast and requires low cost. In addition, it could find numerous applications in surface coating.

The purpose of this paper is to assess the possibility of cross-linking silk fabric using citric acid (CA) as the cross-linking agent and nano-TiO2 (NTO) particles as a catalyst at low temperature and under UV irradiation. This paper also assesses the possibility of treated samples with suitable combinations of CA and NTO to impart multiple functional properties such as self-cleaning and antimicrobial properties.

In this research, ß-cyclodextrin (ß-CD) grafted onto silk fabric using CA as a crosslinking agent and NTO particles as a catalyst through a pad-dry-cure technique and with UVA irradiation. The effects of different concentrations of CA, ß-CD and NTO particles on some properties of the treated samples are evaluated, and the optimum finishing conditions are obtained. The author also investigated the washing durability of the modified product after ten times of washing.

The results showed that CA plays the role of a linking agent through an esterification reaction with the hydroxyl groups of both ß-CD and silk fabrics and improves the durability of materials on the textile surface. Also, the silk fabrics treated with CA only were found to have excellent photocatalytic properties and better antibacterial activity than the control sample and the fabrics treated with a mixture of ß-CD/CA.

This study was conducted to achieve multiple functions such as antibacterial and photocatalytic activities, good dry crease recovery angle and wet crease recovery angle behavior without a significant adverse effect on the Yellowness index and tensile properties for treated silk fabrics.