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The purpose of the paper is to discuss the chemical characterisation of inorganic and organic materials found in electronic systems.

The paper provides an introduction to Fourier transform infrared spectroscopy, which is used for the chemical characterisation and analysis of materials. Examples from recent case studies are given to illustrate the work.

It was found that Fourier transform infrared spectroscopy can successfully identify materials at various stages of their lifecycle. By this means any contaminants and their resulting detrimental effects can be eliminated.

The paper demonstrates how the chemical analysis of a material is conducted, and what can be learned from the investigation.

The purpose of this paper is to discuss the chemical characterization of failures and process materials for microelectronics assembly.

The analytical techniques used for chemical structures and compositions including Fourier transform infrared spectrometer (FTIR), scanning electron microscopy, and energy‐dispersive X‐ray spectroscopy are conducted.

The residues on the golden finger are identified to be the flux used in the assembly processes. Besides, the contaminants on the processed and incoming connector pins are verified to be polyamides (–CONH functional groups) from housing material's residue. Three liquid fluxes used in wave soldering are analyzed by their chemical structure. One flux showing the OH groups at 3430 cm⁻¹ indicates higher acid contents. This consists with the acidic values specified by the supplier. Also, the solder mask under study has ever appeared peeled‐off issue. The FTIR spectra results indicated 62.2 percent degree of curing while vendor's spec is above 70 percent.

The establishment of the Infrared spectra database for fluxes and process materials help determine the root cause of the contaminants to reduce re‐occurrence of similar problems and thus enhance the manufacturing capability. The infrared spectrophotometry technique can be used by professional original design manufacturing and/or electronics manufacturing service, providers to investigate board/component defects during product pilot run stage and volume production.

Gourd fibres (GF) are a natural biodegradable fibre material with excellent mechanical properties and high tensile strength. The use of natural fibres in composite materials has gained popularity in recent years due to their various advantages, including renewability, low cost, low density and biodegradability. Gourd fibre is one such natural fibre that has been identified as a potential reinforcement material for composites. However, it has low surface energy and hydrophobic nature, which makes it difficult to bond with matrix materials such as polyester. To overcome this problem, chemically adapted gourd fibre has been proposed as a solution. Chemical treatment is one of the most widely used methods to improve the properties of natural fibres. This research evaluates the feasibility and effectiveness of incorporating chemically adapted gourd fibre into polyester composites for industrial fabrication. The purpose of this study is to examine the application of chemically modified GF in the production of polyester composite engineering materials.

This work aims to evaluate the effectiveness of chemically adapted gourd fibre in improving the adhesion of gourd fibre with polyester resin in composite fabrication by varying the GF from 5 to 20 wt.%. The study involves the preparation of chemically treated gourd fibre through surface modification using sodium hydroxide (NaOH), permanganate (KMnO₄) and acetic acid (CH₃COOH) coupling agents. The mechanical properties of the modified fibre and composites were investigated. It was then characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) to determine the changes in surface morphology and functional groups.

FTIR characterization showed that NaOH treatment caused cellulose depolymerization and caused a significant increase in the hydroxyl and carboxyl groups, showing improved surface functional groups; KMnO₄ treatment oxidized the fibre surface and caused the formation of surface oxide groups; and acetic acid treatment induced changes that primarily affected the ester and hydroxyl groups. SEM study showed that NaOH treatment changed the surface morphology of the gourd fibre, introduced voids and reduced hydrophilic tendencies. The tensile strength of the modified gourd fibres increased progressively as the concentration of the modification chemicals increased compared to the untreated fibres.

This work presents the designed composite with density, mechanical properties and microstructure, showing remarkable improvements in the engineering properties. An 181.5% improvement in tensile strength and a 56.63% increase in flexural strength were got over that of the unreinforced polyester. The findings from this work will contribute to the understanding of the potential of chemically adapted gourd fibre as a reinforcement material for composites and provide insights into the development of sustainable composite materials.

The development of new advanced materials, such as photopolymerizable resins for use in stereolithography (SLA) and Ti6Al4V manufacture via selective laser melting (SLM) processes, have gained significant attention in recent years. Their accuracy, multi-material capability and application in novel fields, such as implantology, biomedical, aviation and energy industries, underscore the growing importance of these materials. The purpose of this study is oriented toward the application of new advanced materials in stent manufacturing realized by 3D printing technologies.

The methodology for designing personalized medical devices, implies computed tomography (CT) or magnetic resonance (MR) techniques. By realizing segmentation, reverse engineering and deriving a 3D model of a blood vessel, a subsequent stent design is achieved. The tessellation process and 3D printing methods can then be used to produce these parts. In this context, the SLA technology, in close correlation with the new types of developed resins, has brought significant evolution, as demonstrated through the analyses that are realized in the research presented in this study. This study undertakes a comprehensive approach, establishing experimentally the characteristics of two new types of photopolymerizable resins (both undoped and doped with micro-ceramic powders), remarking their great accuracy for 3D modeling in die-casting techniques, especially in the production process of customized stents.

A series of analyses were conducted, including scanning electron microscopy, energy-dispersive X-ray spectroscopy, mapping and roughness tests. Additionally, the structural integrity and molecular bonding of these resins were assessed by Fourier-transform infrared spectroscopy–attenuated total reflectance analysis. The research also explored the possibilities of using metallic alloys for producing the stents, comparing the direct manufacturing methods of stents’ struts by SLM technology using Ti6Al4V with stent models made from photopolymerizable resins using SLA. Furthermore, computer-aided engineering (CAE) simulations for two different stent struts were carried out, providing insights into the potential of using these materials and methods for realizing the production of stents.

This study covers advancements in materials and additive manufacturing methods but also approaches the use of CAE analysis, introducing in this way novel elements to the domain of customized stent manufacturing. The emerging applications of these resins, along with metallic alloys and 3D printing technologies, have brought significant contributions to the biomedical domain, as emphasized in this study. This study concludes by highlighting the current challenges and future research directions in the use of photopolymerizable resins and biocompatible metallic alloys, while also emphasizing the integration of artificial intelligence in the design process of customized stents by taking into consideration the 3D printing technologies that are used for producing these stents.

Examines the seventeenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the fifteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the sixteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

The purpose of this paper is to present a failure analysis of the solder layer in a Darlington power transistor in a TO-3 package.

A failed Darlington power transistor in a TO-3 package was examined by different kinds of failure analysis techniques. At first, internal gas analysis was conducted to measure the atmosphere. Then, scanning acoustic microscopy (SAM) was performed to check the quality of the solder layers in the failed device, and the failure location was determined in the solder layer between chip and substrate. Next, the failed device was decapped to observe the defects. After removing the chip from the substrate, energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) were applied and the main elemental composition of the solder layer was identified.

Internal gas analysis indicated that the moisture and oxygen contents exceeded the allowed maximum value. Large areas of voids were found in the solder layer by SAM. The main elemental compositions of the solder layer were identified by scanning electron microscopy and EDS. Furthermore, the valences of the chemical components in the solder layer were identified by XPS. Except for the few simple substances of the initial solder material, the chemical formulae of oxidation products in the solder layer were deduced. In addition, the root causes are also discussed.

This paper focuses on the solder layer failure of a power transistor. Factors such as the presence of oxygen, voids and other factors, which can cause transistor damage, were comprehensively analyzed. The analysis process is worth learning from and the results can be used to improve the reliability of power devices in this kind of package.

Ballpoint pen ink analysis is important for forensic scientist which can collect valuable information on questioned document. Inks widely used now constitute many substances to improve needed ink characteristics, including the coloring material (dyes or pigments), inks, solvents and resins. The complex components of the inks confront forensic ink chemists with a big challenge to carry out this analysis. However, because of the great importance of determining whether two pieces of written text originated from the same ink, therefore, comparison of different writing inks on a document to forensic scientist, many techniques have been tentatively employed in the ink analysis. In this study, Raman microscope was employed successfully in the analysis of inks. The paper aims to discuss these issues.

Damped or wet samples cannot be analyzed by IR if dehydration is not carried out FTIR observation, because of the extremely strong absorbance of water. Raman spectroscopy can cover the shortage of FTIR spectroscopy because water has weak absorbance in Raman spectroscopy. Raman shifts can give extra peak information because it usually has different positions with FTIR spectroscopy. A Renishaw inVia confocal Raman microscope system with two lasers emitting at 532/633 nm, charge-coupled device detector was employed collecting the Raman spectrum. Laser was chosen for emission in 1-100 percent power depending on the proper energy to get signal strong enough and protect the samples from burning. At least triple-tests were performed for each sample.

The result indicated that Raman spectroscopy could easily remove the interference caused by the paper which could hardly be removed with infrared spectroscopy. No sample preparation was required and only 30 s was needed for each sample in the optimized method. The method proved to be fast, accurate, non-destructive and could be easily applied to the real cases. The primary survey on inks from different market indicated five kinds of inks could be identified. The indicative peaks of each kind of ink (693, 1,150-1,210, 1,280-1,300, 1,360-1,400 and 1,531 cm−1) were summarized. The distributions of the inks in markets were also illustrated. Ink using alkyd resin as connecting materials or copper phthalocyanine as pigment decreased significantly. The data in this study would be helpful for the forensic scientists to identify these inks and examine the questioned document.

No previous studies on the analysis of inks in China market were found to the authors’ best, so the forensic scientists have no idea about the method using Raman for discrimination which proved to be effective, accurate and fast, the indicative peaks of each inks, the distributions in the markets, and therefore, the possibility to encounter specific ink in cases The data in this study would be helpful for the forensic scientists to identify these inks and examine the questioned document.