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The use of organic materials in the construction of aircraft transparencies is introduced by discussing their properties in relation to the requirements of strength and vision of the different types of transparency in the variety of environmental conditions in which they have to operate. The advantages and disadvantages of the particular currently manufactured materials are examined and the way in which their individual properties may best be utilized in the design and construction of transparencies is described and demonstrated by showing examples of proven designs. Present and future developments of both rigid sheet and flexible interlayer materials are discussed, particular reference being made to the development of ‘high temperature’ materials and the use of plastic main plies in combination with glass face plies to form hard‐wearing lightweight laminates. With the present availabilty of the improved acrylic materials, the author looks forward to the possibility of a reduction in the required design factors and a change in the interpretation of the fail‐safe requirements enabling simpler, lighter windows using organic materials to be designed in the future.

The purpose of this paper is to present a comparative study on the characteristics of knitted fabrics used in the manufacturing of apparel, which are produced from organic cotton, lyocell and soybean protein fiber (SPF). It is important for both the environment and society that textile industry continues to adopt more ecofriendly materials and furthermore, pushes to increase awareness regarding these material choices available to the consumer and the corresponding impacts of consumers’ decisions. The use of sustainable fibers may be a starting point for changing the industrial paradigm of the textile industry.

The research presented herein analyzes the potential use of three raw materials used in the development of knitted fabrics: organic cotton, lyocell and SPF. The experimental trials, based on norms, determined the weight, pilling, rupture pressure resistance, absorption by capillarity, dimensional alteration and elasticity. The significance of the experimental results was verified through the analysis of variance, with a confidence interval of 95 percent (p=0.05) and the determination of the optimal regulation of the machine was made through an analysis of the response surface.

The results indicate that each of the studied materials are suitable for textile application; however, the fabrics manufactured from soybean yarn, compared to those manufactured from organic cotton or lyocell, have a higher potential to meet the needs of the costumer.

The discussion regarding sustainability is far reaching on the ways it interacts with human life. As such, the latent need for meeting this new demand presents a unique opportunity for the development of new processes and products. In the case of the textile industry, initiatives are gradually being adopted that make the processes used by the supply chain less damaging to the environment. Clothing and fashion are highly visible elements of society, so consequently, the textile industry serves as an excellent candidate for promoting a sustainable and eco-friendly mindset.

The incorporation of sustainable fibers can serve as a starting point for change to the industrial paradigm existing within the textile industry. To this point, this study intended to analyze the potential implementation of three raw materials – organic cotton, lyocell and SPF – in the development of knitted fabrics. The results indicated that these materials are adequate for textile applications.

The driving forces behind recent significant improvements in organic packages for microelectronic applications are electrical performance, product weight, size and manufacturing cost. A very careful selection of optimum manufacturing processes, equipment and materials, and stringent control of critical manufacturing operations are prerequisites for success in this emerging market place. Major technical and business related challenges to a printed circuit board manufacturer who plans to enter this market are discussed.

This paper aims to investigate the temperature dependence of transfer film formation and friction coefficients in NAO friction materials with four different abrasive components, ZrO₂, ZrSiO₄, Al₂O₃ and Fe₃O₄.

8.5% SnS₂ was added as a lubricating component to friction materials. Friction tests comprised 100 times of consecutive braking application for each friction material under constant temperature of 300°C, 400°C, 500°C and 600°C. After the friction tests, the friction surfaces of the counterpart disks were examined by scanning electron microscope to access the formation of transfer film.

Coefficients of friction depended on not only friction temperature but also friction history which is related to development of transfer film. The effect of the transfer film formation was to reduce the friction coefficients for most friction materials. Quantities of the transfer film formation varied with friction materials; at low temperature below 400° the transfer film formation was most active in the Fe₃O₄ materials, while at 600° it was the most active in the Al₂O₃ material. The effect of the lubricating component SnS₂ was to suppress the formation of transfer film, thus enhancing friction coefficients.

The enhancement of friction coefficients with addition of small amount of lubricating components such as SnS₂ is expected to open a new approach in developing high performance-brake pads.

Temperature was the controlling parameter in the present test. Under these test modes, transfer film could be fully developed to access the role of the transfer film.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0427/

The purpose of this paper is to investigate the effect of [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) on improvement of physical and electrical properties of vanadyl phthalocyanine derivative. The correlation between the physical characteristics of the active layers, comprising vanadyl 2,9,16, 23-tetraphenoxy-29H,31H-phthalocyanine (VOPcPhO) and PCBM, and the electrical properties of metal/organic/metal devices have been studied. The use of soluble vanadyl phthalocyanine derivative makes it very attractive for a variety of applications due to its tunable properties and high solubility.

The sandwich type structures Al/VOPcPhO/Al and Al/VOPcPhO:PCBM/Al were fabricated by spin casting the active organic layers between the top and bottom (aluminum) electrodes. The stand-alone (VOPcPhO) and composite (VOPcPhO:PCBM) thin films were characterized by X-ray diffraction, atomic force microscopy, UV/Vis and Raman spectroscopy. The electronic properties of the metal/organic/metal devices were studied using current-voltage (I-V) characteristics in dark at room temperature.

The values of barrier height for Al/VOPcPhO/Al and Al/VOPcPhO:PCBM/Al devices were obtained from the forward bias I-V curves and were found to be 0.7 eV and 0.62 eV, respectively. The present study indicates that the device employing VOPcPhO:PCBM composite film as the active layer, with better structural and morphological characteristics, results in reduced barrier height at the metal-organic film interface as compared to the one fabricated with the stand-alone film.

It is shown that doping VOPcPhO with PCBM improves the crystallinity, morphology and junction properties.

The spin coating technique provides a simple, less expensive and effective approach for preparing thin films. The soluble VOPcPhO is conveniently dissolved in a number of organic solvents.

The physical properties of the VOPcPhO:PCBM composite thin film and the electrical properties of the composite thin-film-based metal/organic/metal devices have not been reported in the literature, as far as our knowledge is concerned.

SUMMARY The main overall problems associated with transparencies for manned supersonic and hypersonic aircraft are considered. Civil and military concepts are compared in relation to aircraft performance requirements and the reasons for the continuing need for optical transparencies are enumerated. Aircraft performance requirements and typical flight plans show the necessity for designing the transparencies to withstand a considerable range of environmental conditions in addition to the aerodynamic dictates in relation to size, position and shape. These conditions are listed and design feature considerations are discussed in some detail with particular accent on the thermal problems. Reference is made to certain organic and inorganic materials for the basic glazings and the problems associated with the ‘marrying’ of these materials with retaining frame members are discussed. Detail proposals are made for typical windscreen and canopy assemblies. Brief reference is made to the poor reliability shown by many transparencies in present‐day modern aircraft which indicates the need for revision of certain existing test requirements. The proposed new requirements will result in the development of new testing techniques although test factors might well be reduced. The paper concludes with a statement on the importance which is being given to the subject matter by the various bodies in the U.K. and the emphasis which should be placed on the need for the continuation of research and development work in this field.

An overview has been presented on the topic of alternative surface finishes for package I/Os and circuit board features. Aspects of processability and solder joint reliability were described for the following coatings: baseline hot‐dipped, plated, and plated‐and‐fused 100Sn and Sn‐Pb coatings; Ni/Au; Pd, Ni/Pd, and Ni/Pd/Au finishes; and the recently marketed immersion Ag coatings. The Ni/Au coatings appear to provide the all‐around best options in terms of solderability protection and wire bondability. Nickel/Pd finishes offer a slightly reduced level of performance in these areas which is most likely due to variable Pd surface conditions. It is necessary to minimize dissolved Au or Pd contents in the solder material to prevent solder joint embrittlement. Ancillary aspects that include thickness measurement techniques; the importance of finish compatibility with conformal coatings and conductive adhesives; and the need for alternative finishes for the processing of non‐Pb bearing solders are discussed.

In this paper a review is given of the more commonly employed organic polymers for coating and embedment of electronic modules. Following discussion of the basic types and their properties, problems arising from emission of volatiles from encapsulants are outlined and the importance of considering these in early design stages is stressed.

CSP (chip scale packaging) and flip chip area array technologies are emerging within the electronics packaging industry to provide solutions capable of fulfilling the technological demands of computer, telecom and consumer electronic products. However, the full potential of area array attach can only be realised if the next level of interconnect is capable of supporting the fine pitch and high I/O characteristics of emerging CSP and flip chip technology. Celestica has addressed this issue by investigating next generation printed circuit board (PCB) technology, to assess the capability of organic based laminate as a high density interconnect. This paper describes the manufacturing experiments performed to produce a laser microvia interconnect solution. The mechanical performance of the interconnect is also presented to confirm its compatibility with area array assembly.

The possibility of the corrosion of metals due to contact with plastic materials has been known for a very long time. This is a matter of consequence, especially in the instrument and the lighter electrical sections of engineering industry. Therefore much attention has been given to the subject by technologists concerned in these fields.