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This study aims to the effect of NaF, Li₂CO₃ and H₃BO₃ minerals was investigated, and the best mineralizer was found to be H₃BO₃. Furthermore, the effect of temperature was investigated, and the synthesized samples were calcined at temperatures of 1100, 1200 and 1300 °C to select the optimum calcination temperature.

This study was aimed at thoroughly investigating the effects of mineralizer addition and temperature on the synthesis of malayaite pink pigment based on raw materials of SnCl₂-SiO₂-Ca(OH)₂-K₂Cr₂O₇. To this end, the optimization of the synthesis parameters such as mineralizer addition and temperature was completely perused.

The optimum temperature was 1300 °C, and the color efficiency of pigments was evaluated by colorimetric (CIE L*a*b* system) analysis, and these parameters were close to those of industrial pigments.

To the best of the authors’ knowledge, for the first time, the effect of mineralizer addition and temperature on the synthesis of malayaite pink pigment was investigated through the sol-gel method. Herein, different parameters were optimized to propose a novel pigment with a much better performance.

The microstructure difference and enthalpy changes have been investigated by scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) during the as-cast ageing process. After the as-cast ageing process, the eutectic silicon and α-Al is in the ideal state for the alloy with 0.08 wt% mischmetal (MM) addition. The energy of the phase transformations is 5.8 J/g during the isothermal process, when Al-11%Si-0.27%Mg alloy is aged at 150°C. When the additive contents of MM are 0.03, 0.06, 0.08 and 0.1 wt%, respectively, the energies of phase transformations are 4.98, 1.39, 1.07 and 1.25 J/g correspondingly. It is shown that the energies of phase transformations decrease gradually as the MM content increases from 0 wt% to 0.08 wt%; the energies then increase upon further addition of the MM concentration from 0.08 wt% to 0.1 wt% in the as-cast ageing process. Furthermore, the beginning time of phase transformations is delayed with the MM addition.

The increase in semiconductor integration level has led to complex Integrated Circuits (ICs) characterised by an increasing number of I/O, such that dies with 40 to 84 metallised pads are currently manufactured and frequently used in modern electronic systems. The advent from 1980 onwards of these LSI‐VLSI semiconductors requires new economical micropackages to be devised that can be adapted to surface mounting techniques on Hybrid Integrated Circuits (HICs) and Printed Circuits Boards (PCBs). Plastic encapsulation using a transfer moulded epoxy resin is a widely used method for packaging silicon devices because of the reduced manufacturing cost for large volumes. This economic criterion, which is considered with widespread interest in the electronics industry, has recently led the major semiconductor manufacturers to produce Plastic Leaded Chip Carriers (PLCCs) with up to 84 J bend connections on 1·27 mm pitch, and Mini Quad Packs with 40 to 84 Z bend pins on 0·75∼0·80mm centres. However, until now, a significant number of ICs, such as full custom circuits, are not yet available in any packaged form. Thus, in order to take advantage of the compactness offered by micropackages without being under component manufacturers' constraints for packaged LSI needs, it was decided at the Microelectronics Division of CIT‐Alcatel to develop a flexible semiconductor encapsulation technology which does not require any moulding equipment. The process involved has led to the development of a small economical package with 52 peripheral Z bend leads on 0·75 mm centres which has been evaluated. This original LSI carrier, named Plastic Composite Package (PCP) because of its special feature, is perfectly suited to the specific needs of multilayer HICs for all non‐military applications. In addition, another PCP format with 68 pins on 0·635 mm centres, designed for LSI Industrial applications, has been investigated. The purpose of this paper is to explain the specific needs in the hybrid industry and to give the authors' views on trends in LSI‐VLSI plastic encapsulation. Moreover, the PCP manufacturing process is described, the evaluation results being discussed as well as the economic aspect.

To study the interface properties of anisotropic conductive adhesives (ACAs) and improve the electrical properties of ACA joints as a replacement for Sn/Pb solder in the electronics industry.

In this study, different types of self‐assembled monolayer (SAM) compounds were introduced into the interface between the metal filler and the substrate bond pad. The formation of these SAMs on gold and silver surface and their thermal stability were investigated by measuring the contact angles with water of these SAM coated surfaces. The SAM compounds used had either hydrophilic or hydrophobic tail groups, and included octadecanethiol (ODT), mercpatoacetic acid (MAA), 1,4‐benzenedithiol (dithiol) and malonic acid (acid M). Epoxy resins with two different curing temperatures were used as polymer matrices for the ACA formulations. The electrical properties of ACA joints containing these SAMs were studied by measuring their current‐voltage relationship.

The results show that SAMs can be successfully coated onto specific metal surfaces, depending on the affinity of their functional groups with the specific metal. The SAM treated ACA joints show much lower resistance at the same applied current than non‐treated joints, and the effect on the low curing temperature epoxy matrices was more significant. Nano‐Ag filled ACAs show more significant improvements in their electrical properties due to the greater surface area and higher surface energy of nano‐particles and consequently their higher thermal stability when coated with SAMs.

This paper is the first to use functional organic monolayers to enhance the interface properties of electrically conductive adhesives and, in particular, for ACAs.

EXPERIMENTAL WORK AND RESULTS I. Physical Methods of Polymer Modification PHYSICAL methods can be used to modify the structure of super‐molecules in order to control the mechanical properties of the polymer and revise the frictional properties over a wide range while keeping the chemical structure and molecular weight unchanged.

To demonstrate a method of selecting base materials for lead‐free processing based on the kinetics of decomposition.

The paper describes the calculation of Arrhenius kinetic parameters from common “time to delamination” data (T₂₆₀). Delamination is correlated to a certain conversion into the decomposition reaction. With both of these parameters, various soldering scenarios are analysed.

The findings highlight the fact that conventional FR‐4 materials are only good for a few reflow cycles. A higher number of reflow cycles can only be fulfilled with RoHS compliant base materials. However, rework and repair may even shift those more thermally resiliant materials over the limit. The peak temperatures are over proportionally responsible for delamination failures and need to be controlled carefully.

The value of the paper lies in its ability to provide guidance on the selection of base materials to comply with various soldering processes. A model has been developed that is able to predict failure limit for a given base material and a given process.

In a high temperature tribometer, stationary carbon has been tested against different rotating ceramics (SiC, Si₃N₄, Al₂O₃, WC‐6Ni, MgO‐ZrO₂, (Ti, Mo)(C, N)) and stainless steel (DIN 1.4876). The rotating discs were grinded, polished and/or lapped. For most material combinations, the wear morphology is known from available literature. A transfer film with a typical wear pattern was found on the rotating disc. The combination of antimony graphite EK3245 against MgO‐ZrO₂ did not form carbonaceous transfer layer. Through advanced variation of the roughness up to R_pk=0.011 μm, the wear rate has been reduced to K_v ≈ 3.5×10⁻⁸ mm³/N m at a stable coefficient of friction in a “millirange” of μ∼0.008 for a sliding distance of 20.000 m.

As multifunctional additives, ZDDP, which provides excellent oxidation resistance and superior antiwear properties, has been used widely in lubricants, however, it shows oppositional effect with friction modifiers when used together. In this paper, an attempt is made to find a novel kind of borate ester which can be used as potential substitute for ZDDP.

A novel borate ester containing dialkylthiophosphate group was prepared and characterized. Its tribological properties as an additive in synthetic ester were evaluated using a four‐ball tribometer and antioxidative ability tested by pressurized differential scanning calorimetry (PDSC). Thermal degradation tests were conducted to identify its thermal stabilities using thermogravimetric analyzer (TGA). The worn surface of the steel ball was investigated by X‐ray photoelectron spectroscopy (XPS) and the antiwear mechanism of the additive was preliminarily discussed.

Results show the additive possesses outstanding loading‐carrying and friction‐reducing properties, compared with ZDDP, and can improve antiwear properties of the base oil dramatically. Moreover, it also has excellent antioxidation performance and thermal stability.

This paper provides a multifunctional ashless additive which possesses excellent tribological properties, and gives another selection for industrial applications in which ZDDP is needed.

The fast growing concern for maintaining integrity of the environment has built up development of environmentally‐adapted lubricants. Because of their toxicity, most of the traditional lubricating additives cannot be used in this kind of lubricant. The purpose of this paper is to find a borate ester derivative which can be used as a multifunctional additive in rapeseed oils (RSO).

A borated S‐2‐hydroxypropyl N, N‐dibutyl dithiocarbamate (BDTC) was synthesized and characterized. Its tribological properties in rapeseed oil as multifunctional additive were evaluated, using a four‐ball tribometer and compared with one kind of commercial MoDTC. In addition, its thermal stability was identified using TGA and antioxidative ability tested by PDSC. The action mechanism of BDTC was studied by X‐ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and atmospheric pressure chemical ionization mass spectrometer (APCI/MS) analysis.

Results show that BDTC exhibits high thermal stability, possesses comprehensive tribological performance in rapeseed oil, and has evident effect in controlling the oxidation of RSO. Analysis of worn surface indicates that BDTC was decomposed and reacted with metal during the friction process. The lubricating film mainly contains inorganic boron compound (B₂O₃), organic nitrogen derivatives and FeSO₄.

This paper provides a borate ester derivative which possesses excellent tribological properties and can be used as a multifunctional ashless additive in environmentally‐adapted lubricants. Furthermore, an innovative method, APCI/MS, was used to analyze the tribo‐fragmentation behavior of BDTC.

The purpose of this study is to suggest the joint use of computer-aided design (CAD) and additive manufacturing (AM) technology for the fabrication of custom-made moulds, designed for the manufacture of polymethyl methacrylate (PMMA) implants for cranio-maxillofacial reconstruction to reduce their fabrication time. Even though tailor-made skull prostheses with a high technological level and state-of-the-art materials are available in the market, they are not always accessible to the general population in developing countries.

Computed tomography data were handled to create a three-dimensional (3D) model of the injury of the patient, by reconstructing Digital Imaging and Communications in Medicine (DICOM) images into an Standard Tessellation Language (STL) file that was further used to design the corresponding implant using CAD software. Accordingly, a two-piece core and cavity moulds that replicated the implant geometry was also CAD designed. The 3D-CAD data were sent to an AM machine (fused deposition modelling) and the moulds were fabricated using polycarbonate as thermoplastic material. A reacting mixture to produce PMMA was poured directly into the fabricated moulds, and left to polymerise until cure. Finally, a clear bubble-free case of study PMMA implant was obtained.

The fabrication of CAD-designed moulds with AM, replacing the production of the injury model, resulted in the reduction of the lead-time in the manufacturing of PMMA around 45 per cent. Additionally, the implant showed better fit than the one produced by conventional process. The use of AM moulds for the fabrication of PMMA implants has demonstrated the reduction in lead-time, which potentially can reduce the waiting time for patients.

Currently, the demand of cranio-maxillofacial implants at only the Hospital General de México “Dr Eduardo Liceaga” (HGM) is 4,000 implants per year, and the average waiting time for each patient is between 5 and 10 weeks, including third-party services’ delays and the time needed to obtain the economical resources by the patient. Public hospitals in Mexico lack manufacturing facilities, so patients have to make use of laboratories abroad and most of the population have no access to them. The implementation of this suggested procedure in public hospitals may improve the accuracy of the implant, increase the number of patients attended per year (up to 83 per cent) and the reduction in waiting time can also reduce mortality and infection rates.

The authors of this paper suggest the joint use of CAD and AM technologies to significantly reduce the production time of PMMA implants by producing moulds rather than the injury model, maintaining the general terms and known steps of the process already established for PMMA implants.