title: Long‐term residual properties and durability of glass fiber reinforced polymer composite exposed to alkaline solution and natural weather for a decade

authors: Ahmad Sawpan, Moyeenuddin

abstract: This paper presents a comprehensive analysis of the residual thermal and mechanical properties of pultruded glass fiber reinforced polymer composite bars following a decade of conditioning in an alkaline solution and exposure to natural weather conditions. The study focuses on evaluating the changes in the glass transition temperature (Tg) of the polymer matrix and its impact on the bar's mechanical performance. The results indicate that the Tg retained approximately 94.7% of its initial value, with the decrease attributed to the plasticizing effect of absorbed water. The flexural modulus, flexural strength, and transverse shear strength were found to retain 91.8%, 77.2%, and 97.3% of their original values, respectively. The reductions in strength and stiffness were primarily attributed to a weakening in the bonding between the fibers and the polymer matrix. Fractographic analysis revealed that the failure of the plasticized and softened polymer matrix contributed to the observed reductions in strength. Interestingly, the short beam shear strength remained relatively unchanged, as the diffusion of water into the core of the bars at ambient temperatures had a minimal effect. This slower water diffusion in the core led to insignificant degradation of the short beam shear strength.

Highlights
○ GFRP bars were exposed to alkaline solution and natural weather for a decade.
○ The water diffusion was a key factor in determining the residual properties of the GFRP bars.
○ The absorbed water plasticises the polymer matrix in GFRP bars.
○ The mechanical property losses in GFRP bars were associated with changes in the matrix property.

text: Long‐term residual properties and durability of glass fiber reinforced polymer composite exposed to alkaline solution and natural weather for a decade This paper presents a comprehensive analysis of the residual thermal and mechanical properties of pultruded glass fiber reinforced polymer composite bars following a decade of conditioning in an alkaline solution and exposure to natural weather conditions. The study focuses on evaluating the changes in the glass transition temperature (Tg) of the polymer matrix and its impact on the bar's mechanical performance. The results indicate that the Tg retained approximately 94.7% of its initial value, with the decrease attributed to the plasticizing effect of absorbed water. The flexural modulus, flexural strength, and transverse shear strength were found to retain 91.8%, 77.2%, and 97.3% of their original values, respectively. The reductions in strength and stiffness were primarily attributed to a weakening in the bonding between the fibers and the polymer matrix. Fractographic analysis revealed that the failure of the plasticized and softened polymer matrix contributed to the observed reductions in strength. Interestingly, the short beam shear strength remained relatively unchanged, as the diffusion of water into the core of the bars at ambient temperatures had a minimal effect. This slower water diffusion in the core led to insignificant degradation of the short beam shear strength.

Highlights
○ GFRP bars were exposed to alkaline solution and natural weather for a decade.
○ The water diffusion was a key factor in determining the residual properties of the GFRP bars.
○ The absorbed water plasticises the polymer matrix in GFRP bars.
○ The mechanical property losses in GFRP bars were associated with changes in the matrix property.

year: 2023-10-09

title: Spray Dryer Exhaust Heat Recovery: A Techno-economic Assessment Model

authors: Walmsley, Timothy Gordon

abstract: This paper discusses the spray dryer exhaust heat recovery in Milk Power Production.

text: Spray Dryer Exhaust Heat Recovery: A Techno-economic Assessment Model This paper discusses the spray dryer exhaust heat recovery in Milk Power Production.

year: 2014-08-26

title: New Zealand and Maori land trusts

authors: Chevalier-Watts, Juliet

abstract: New Zealand, as in other jurisdictions, has a range of recognized trusts that would be familiar to many. These include express trusts, resulting trusts, constructive trusts, and charitable trusts. Perhaps more unfamiliar, at least to those outside New Zealand, are trusts that are unique to the New Zealand legal landscape and that are specific to Maori land. This article explores the relevance, and importance, of such trusts within New Zealand—Aotearoa. In doing so, the author considers a number of these Maori land trusts, and critically evaluates a range of issues, which includes governance; conflict of interest; unsatisfactory conduct; and dysfunction. While Maori land trusts are subject to the general laws of trust, it can be seen from the article how valuable such trusts are in recognizing and protecting Maori interests. As such, their unique nature reflects their fundamental relevance in indigenous culture, and also generally as an effective management tool for much Maori land.

text: New Zealand and Maori land trusts New Zealand, as in other jurisdictions, has a range of recognized trusts that would be familiar to many. These include express trusts, resulting trusts, constructive trusts, and charitable trusts. Perhaps more unfamiliar, at least to those outside New Zealand, are trusts that are unique to the New Zealand legal landscape and that are specific to Maori land. This article explores the relevance, and importance, of such trusts within New Zealand—Aotearoa. In doing so, the author considers a number of these Maori land trusts, and critically evaluates a range of issues, which includes governance; conflict of interest; unsatisfactory conduct; and dysfunction. While Maori land trusts are subject to the general laws of trust, it can be seen from the article how valuable such trusts are in recognizing and protecting Maori interests. As such, their unique nature reflects their fundamental relevance in indigenous culture, and also generally as an effective management tool for much Maori land.

year: 2016