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This study aimed to investigate the collective effects of bending load and hygrothermal aging on glass fibre-reinforced plastics (GFRP) due to the fact that stress and water absorption is inevitable during GFRP applications.

The water boiling method was used to study the moisture absorption, desorption behaviour and evaluate the performance of GFRP laminates under loading in this article. The moisture diffusion of laminates is characterized in three aging conditions (25°C, 45°C and 65°C water), along with three levels of bending load coefficients (0, 0.3 and 0.6). The moisture diffusion coefficients are determined through the curve fitting method of the experimental data of the initial process, based on the Fickian diffusion model. Moreover, the laminates’ performance is further discussed after adequate environmental aging and loading.

It was found that moisture absorption is promoted by the presence of bending load and boiling during this study. The absorption diffusion coefficient and moisture equilibrium content of the specimens increased with an increasing loading ratio and temperature. The bending strength of the laminate varied according to a contrary trend. Furthermore, the desorbed moisture content is found to be much higher after higher levels of bending load because it is harder to desorb the moisture in the interfaces and micro cracks.

Collective effects of bending load and hygrothermal aging promote the absorption and result in accelerating property degradation of GFRP. It is significant to focus on these effects on the failure of GFRP.

A novel unit was designed to simulate the various loading acted on containers in this work.

The purpose of this paper was to study the combined effect of hygro and thermo-mechanical behavior on a plastic encapsulated micro-electro-mechanical systems (MEMS) package during the reflow process after exposed to a humid environment for a prolonged time. Plastic encapsulated electronic packages absorb moisture when they are subjected to humid ambient conditions.

Thus, a comprehensive stress model is established for a three-axis accelerometer MEMS package, with detailed considerations of fundamentals of mechanics such as heat transfer, moisture diffusion and hygro-thermo-mechanical stress. In this study, the mold compound is considered to be the most critical plastic material in MEMS package. Other plastic components of thin film materials can be disregarded due to their small sizes such as die attach and Bismaleimide Triazine (BT) core, even though they are also susceptible to moisture. Thus, only the moisture-induced properties of mold compound were obtained from the proposed experiments. From the desorption measurement after preconditioning at 85°C/85 per cent relative humidity (RH), the saturated moisture content and diffusivity were obtained by curve fitting the data to Fick’s equation. In addition, a new experimental setup was devised using the digital image correlation system together with a precision weight scale to obtain the coefficient of hygroscopic swelling (CHS) at different temperatures.

The experimental results show that the diffusion coefficient of mold compound material follows Arrhenius equation well. Also, it is shown that the CHS of mold compound increases as temperature increases. Experimentally obtained moisture properties were then used to analyze the combined behavior (thermo-hygro-mechanical) of fully saturated MEMS package during the reflow process using a finite element analysis (FEA) with the classical analogy method. Finally, the warpage and stresses inside the MEMS package were analyzed to compare the effects of hygroscopic, thermal and hygro-thermo-mechancal behaviors.

In this study, unlike the other researches, the moisture effects are investigated specifically for MEMS package which is relatively smaller in scale than conventional electronic packages. Also, as a conjugated situation, MEMS package experiences both humid and temperature during the moisture resistance test. Thus, major objective of this study is to verify stress state inside MEMS package during the reflow process which follows the preconditioning at 85°C/85 per cent RH. To quantify the stresses in the package, accurate information of material properties is experimentally obtained and used to improve modeling accuracy.

The purpose of this paper is to provide the details of developments to researchers in test apparatus and evaluation methods to rate the thermal protective performance (TPP) of firefighters’ clothing under high-temperature and high-humidity condition.

This review paper describes the influence laws of moisture on thermal protection and the moisture distribution in actual fire environment. Different evaluation methods used for assessing the effect of moisture on the TPP were investigated, with an emphasis on test devices, evaluation indexes as well as their relationship and limitations.

The moisture from the ambient, clothing and human perspiration plays an important role in determining the TPP of firefighter protective clothing. It is obvious that research on moisture-driven heat transfer in firefighter’s clothing system are comparatively little, primarily focussing on pre-wetted methods of multi-layer fabric. Further studies should be conducted to develop more standardized moistening systems and improve the current calculation methods for evaluating the performance of protective clothing. New explorations for heat and moisture transfer mechanism in protective clothing should be investigated.

Protective clothing is the efficient way to provide fire-fighting occupational safety. To accurately evaluate the TPP of protective clothing under high-temperature and high-humidity condition will help to optimize the clothing performance and choose the proper clothing for providing firefighters with the best protection under multiple thermal hazards.

This paper is offered as a concise reference for scientific community further research in the area of the TPP evaluation methods under high-temperature and high-humidity condition.

This paper aims to optimize feed moisture contents, barrel temperatures, blending ratios of maize and lupine for processing of protein-rich best quality extruded product using a twin-screw extruder.

A three-factor three-level response surface methodology by Box-Behnken Design was applied to evaluate the effect of selected processing conditions of blending ratios of lupine (10-20 per cent), barrel temperatures (120°C-150°C) and feed moisture content (14-18 per cent) on functional, nutritional and sensory characteristics of produced snack food.

The results of functional properties such as radial expansion ratio, bulk density, water absorption index, water solubility index observed as 0.71-1.2, 0.33-0.92 g/cc, 4.4-6.4 per cent and 10.2-15.1 per cent, respectively. The snack food showed the moisture 5.6-7.2 per cent, protein 8.1-18.1 per cent, fiber 1.6-2.7 per cent, ash 1.6-2.2 per cent and carbohydrate 64.8-81.4 per cent. The independent variables (lupine blending ratio, barrel temperature and feed moisture content) posed significant effects on expansion ration (p = 0.0030), bulk density (p = 0.0026), water absorption index (p = 0.0075) and water-solubility index (p = 0.0116). Higher blending ratio of lupine was increase in the bulk density and water solubility index, but decrease in expansion ratio and water absorption index of snack food. Higher feed moisture content was led to a reduction in expansion ratio and water-soluble index of snack food. Whereas, higher feed moisture contents was lead to rise in bulk density and water absorption index. Fiber (p = 0.0145), ash (p = 0.0343) and carbohydrate (p = 0.0001) contents were significantly depended on blending ratio. Blending of lupine 15.06 per cent, barrel temperature of 150 °C and feed moisture content of 14.0 per cent produced the snack food with desirability value of 72.8 per cent.

Protein malnutrition is one of the major problems in child development in under developed countries including Ethiopia. Maize is a top producer in the country but least appreciated for cost. Lupine is one of the undervalued produce consumed in Ethiopia after boiling. Still data on the utilization of maize and lupine in the extruded snack preparation was very limited. Optimization of moisture and barrel temperatures for this snack was not reported clearly yet.

In this paper, a solid circular cylinder of finite length occupying the space 0⩽r⩽1, 0⩽z⩽h is considered. The purpose of this paper is to adopt a linear hygrothermal effect to analyze the unsteady state responses in a finite long solid cylinder subjected to axisymmetric hygrothermal loading T=T_R and C=C_R at the surface. The analytical solution of temperature, moisture and thermal stresses is obtained by using the integral transform technique. The coupling and uncoupling effects of temperature, moisture and thermal stresses are discussed for a graphite fiber-reinforced epoxy matrix composite material (T300/5208). The numerical results of transient response hygrothermoelastic field are presented graphically.

In the present problem, hygrothermoelastic response of a finite solid circular cylinder has been investigated by integral transform technique consisting of Laplace transform, Hankel transform and Fourier-cosine transform. The problem is investigated subjected to prescribed sources. Numerical algorithm has been developed for numerical computation.

The analytical solution of temperature, moisture and thermal stresses is obtained by using the integral transform technique. The coupling and uncoupling effects of temperature, moisture and thermal stresses are discussed for a graphite fiber-reinforced epoxy matrix composite material (T300/5208). The numerical results of transient response hygrothermoelastic field are presented graphically.

The work presented here is mostly hypothetical in nature and totally mathematical.

It may be useful for composite materials, composite laminated plates in hygrothermal environment. Also it is having the applications in hygrothermal field where porous media exposed to heat and moisture. The problem investigated will be beneficial for the researcher working in the field thermoelastic diffusion and hygrothermoelastic materials.

Till date, the other authors did the research work on hygrothermal effect of an infinitely long cylinder without thickness. In this paper, the authors consider finite solid cylinder with finite length and discuss the hygrothermal effect within a small range. Second, the material properties are both homogenous and isotropic and are independent of both temperature and moisture.

The purpose of the paper is to prepare the hygrothermal model with fraction order theory in a mathematical aspect.

In this study, linear hygrothermoelastic theory is adopted to analyze and discuss the memory effect in a finite length hollow cylinder subjected to hygrothermal loading.

Analytical solutions of temperature, moisture and stresses are obtained in this study by using the decoupling technique and the method of Integral transform.

The paper deals with the original work based on hygrothermal response in hollow cylinder by theory of uncoupled-coupled heat and moisture.

The purpose of this paper is to explore the synergic effect of wild turmeric (Curcuma Aromatica Salisb.) and holy basil (Ocimum Tenuiflorum L.) combination herbal extracts treatment on the moisture management properties of cotton, lyocell and micro-denier single jersey knitted fabrics and the factors affecting it, which is intended for the development of healthcare apparel products.

The pre-treated single jersey knitted fabrics of cotton, lyocell and micro-denier polyester fabrics were given finishing treatment with the wild turmeric (Curcuma Aromatica Salisb.) and holy basil (Ocimum Tenuiflorum L.) combination herbal extract proportions of 100%:0%, 75%:25%,50%:50%; 25%:75% and 0%:100%. The D-optimal factorial design developed using Design Expert software was used for the study. The finishing treatments were carried out using the pad−dry−cure method. The aim of the work is to find out the influence of combination herbal extract proportion, textile material and their interaction effect on the moisture management properties.

The ANOVA results revealed that the overall moisture management properties of single jersey knitted fabrics are influenced by the material type, combination herbal extract proportion and the interaction between material type and the combination herbal extracts proportion. The overall moisture management properties of combination herbal extracts treated cotton single jersey fabrics are found to be better than that of lyocell and micro-denier polyester fabrics due to their excellent accumulative one-way transport capability after the finishing treatment. Among the combination herbal extract proportions, 50:50 per cent combination herbal extract proportion was found to be better than other proportions.

The study on the moisture management properties of combination herbal extracts of wild turmeric (Curcuma Aromatica Salisb.) and holy basil (Ocimum Tenuiflorum L.) is a novel attempt to explore the synergic effect of active constituents in both the herbs.

Wetting wood plastic composites (WPCs) prior to testing can be challenging because of the inherent water repellency of the plastic. The purpose of this paper is to explore the use of heating and wetting to accelerate moisture uptake on two WPCs.

Full size samples of the two WPCs were immersed in water at various temperatures or heated in an autoclave. Samples were removed periodically and dissected to determine the moisture profile by oven drying and weighing.

Moisture uptake is accelerated by heating, but the effect is mainly confined to the outer 5 mm of the samples. Moisture levels deeper in the samples are largely unaffected.

Moisture uptake can be enhanced by heating, but the inability to increase moisture levels deeper in the wood suggests that tests assessing the role of moisture on WPC properties should use thinner specimens to ensure that moisture is well distributed in the materials.

The results suggest the need for a re‐evaluation of test methodologies for WPCs where moisture uptake is an integral part of the procedures to more closely align the methods to the WPC/moisture behaviour.

This paper will help researchers develop better methods for assessing the role of moisture in WPC behaviour.

This paper focuses on the fluid-structure interaction (FSI) analysis of moisture induced stress for the flip chip ball grid array (FCBGA) package with hydrophobic and hydrophilic materials during the reflow soldering process. The purpose of this paper is to analyze the influence of moisture concentration and FCBGA with hydrophobic material on induced pressure and stress in the package at varies times.

The present study analyzed the warpage deformation during the reflow process via visual inspection machine (complied to Joint Electron Device Engineering Council standard) and FSI simulation by using ANSYS/FLUENT package. The direct concentration approach is used to model moisture diffusion and ANSYS is used to predict the Von-Misses stress. Models of Test Vehicle 1 (similar to Xie et al., 2009b) and Test Vehicle 2 (FCBGA package) with the combination of hydrophobic and hydrophilic materials are performed. The simulation for different moisture concentrations with reflows process time has been conducted.

The results from the mechanical reliability study indicate that the FSI analysis is found to be in good agreement with the published study and acceptable agreement with the experimental result. The maximum Von-Misses stress induced by the moisture significantly increased on FCBGA with hydrophobic material compared to FCBGA with a hydrophilic material. The presence of hydrophobic material that hinders the moisture desorption process. The analysis also illustrated the moisture could very possibly reside in electronic packaging and developed beyond saturated vapor into superheated vapor or compressed liquid, which exposed electronic packaging to higher stresses.

The findings provide valuable guidelines and references to engineers and packaging designers during the reflow soldering process in the microelectronics industry.

Studies on the influence of moisture concentration and hydrophobic material are still limited and studies on FCBGA package warpage under reflow process involving the effect of hydrophobic and hydrophilic materials are rarely reported. Thus, this study is important to effectively bridge the research gap and yield appropriate guidelines in the microelectronics industry.

This paper investigates the influence of moisture absorption on the mechanical properties of carbon/epoxy composites.

Three types of specimens are prepared, which are for longitudinal, transverse and shear tests. Specimens are immersed in distilled water at 70°C for 1, 3 and 9 months. These correspond to the moisture content of 2.2, 3.8 and 5.3%.

Compared to the values at dry condition, the longitudinal modulus, shear modulus and Poisson's ratio are invariant with the moisture content. However, the transverse modulus, transverse strength and shear strength are sensitive to moisture attack. The maximum degradation is 33%, 76 and 33% for the three properties, respectively. It is also worth to note that the longitudinal tensile strength is stable at 1 and 9 months of immersion. However, at 3-months ageing period, there is only 67% of the longitudinal tensile strength retained.

The experimental results are fitted with a residual property model. Results show comparatively good fit, with a difference within 16% except the longitudinal tensile strength at 9-months immersion. This highlights that the model is not suitable to fit the experimental data with a fluctuated trend.