Mussels repair shell damage despite limitations imposed by ocean acidification

Bivalves frequently withstand shell boring attempts by predatory gastropods that result in shell damage that must be quickly repaired to ensure survival. While the processes that underlie larval shell development have been extensively studied within the context of ocean acidification (OA), it remains unclear whether shell repair is impaired by elevated pCO2. To better understand the stereotypical shell repair process, we monitored mussels (Mytilus edulis) with sublethal shell damage within both field and laboratory conditions to characterize the deposition rate, mineral composition, and structural integrity of repaired shell. These results were then compared with a laboratory experiment wherein mussels (Mytilus trossulus) repaired shell damage in one of seven pCO2 treatments (400–2500 µatm). Shell repair proceeded through four distinct stages; shell damage was first covered with an organic film, then mineralized over the course of weeks, acquiring the appearance of nacre after 8 weeks. OA did not impact the ability of mussels to close drill holes, nor the strength or density of the repaired shell after 10-weeks, as measured through mechanical testing and µCT analysis. However, as mussels progressed through each repair stage, significant interactions between pCO2, the length of exposure to treatment conditions, and the strength, inorganic content, and physiological condition of mussels within OA treatments were observed. These results suggest that, while OA may not prevent mussels from repairing shell damage, sustained exposure to elevated pCO2 may induce physiological stress responses that impose energetic constraints on the shell repair process.

Multimodal spectroscopy with chemometrics for the forensic analysis of the inorganic content of Western Australian sandy soils

This study demonstrates a multi-modal analytical sequence suited to the characterisation of sandy soils, which remain an underutilised form of forensic trace evidence. Within the Swan Coastal Plain in Perth, Western Australia, most soils are heavily leached with only small deviations in their mineral compositions. Traditional soil analyses are hence rendered inappropriate for use due to the lack of clay and organic matter. This has led to inorganic methods of analysis predominating, in addition to experimentation with modified techniques. One example is utilisation of the quartz-recovered fine fraction, which is suitable for dry, quartz-dominated sandy soils. In this study, preliminary investigations used the spectroscopic techniques microspectrophotometry, infrared spectroscopy, and x-ray diffraction, to develop a multi-faceted approach for the forensic analysis of the quartz fine fraction of soils. These data were then combined with principal component analysis to demonstrate how chemometrics can assist with objective characterisation and differentiation of sandy soil samples for forensic purposes. Chemometric analysis has not previously been attempted with data obtained from the quartz fine fraction. This methodology is transferable to other jurisdictions where dry, sandy soils predominate.

Study the Structure Characterization of Porcelain Formulation at Different Sludge Content

Porcelain formulation in the form of pellets have been studied by substituted fluxing materials with treated FGD sludge at different percentages. In this work, treated FGD sludge was added in percentages from 5% up to 15% uniaxially pressed at 11 MPa, dried and then sintered at temperature 1200 °C for 3 hours. Weight loss, volume shrinkage/expand, bulk density, densification, porosity and flexural strength were investigated on sintered samples. This demonstrated that the treated FGD sludge addition in porcelain formulation has influenced on the sintered samples. It was concluded that the treated FGD sludge waste could be used as a suitable raw material source for production of porous porcelain ceramic due to their organic and inorganic content.

Influence of Injection Moulding Parameters on Electrical Conductivity of Polypropylene-Graphite Composite Bipolar Plates for Hydrogen Fuel Cells

News on Green Energy and Green Hydrogen is spread on popular and academic media. When energy is obtained from sunlight, wind or water, we call it Green Energy. When hydrogen is obtained from electrolysis with Green Energy, we call it Green Hydrogen. Hydrogen Fuel Cells are electrochemical devices that convert hydrogen and oxygen s chemical energy into electricity and heat energy with high efficiency and contribute to the decarbonisation of the power supply. Bipolar plates, essential components of the fuel cells, made in polymer-carbon composites, are an economical alternative to the stainless steel, titan and graphite, traditional materials. Our experiments have used a polypropylene matrix filled with graphite with a total inorganic content of 87%, which contributes to high electrical and thermic conductivity but strongly influences the viscosity, flow, pressures, temperatures, and then challenging to process. Injection Moulding of thermoplastics is a technology widespread in all fields of activities and considerable potential. In this paper, the experiments design is highlighted in choosing the factors. A debate regarding the filling, packing, holding pressures, and the last decades approach and optimisation of injection moulding parameters with the Taguchi Method is presented. Conclusions on the injection moulding process of the bipolar plate made of a polypropylene-graphite composite, the parameters influence with direct effects on the fuel stack s performance are presented. The combined melt and mould temperatures influence most electrical conductivity by better contacting the electrically conductive particles through the polymer s melted layer. The injection pressure influences the mass and thickness of the product and the electrical conductivity by better packing. Furthermore, we suggest an adapted formula to predict the injection pressure considering the inorganic content and the process temperatures in agreement with the experiments.

Demineralization of Miscanthus Biocrude Obtained from Catalytic Hydrothermal Liquefaction: Conditioning through Acid Washing

In this contribution, we successfully applied demineralization (i.e., solvent-assisted separation and acid washing) for the removal of carbonaceous solids and inorganics from a biocrude obtained from the catalytic hydrothermal liquefaction (HTL) of Miscanthus. The experimental results of all six employed acids showed that 0.1 M H2SO4 was the most effective and significantly reduced metallic (Fe by 93.9%, <15 µg/g and Mg by 95.6%, 2.1 µg/g) and ash content (by 92.7% to 337 µg/g) from the already filtered biocrude. The utilized demineralizing agents caused a loss of nitrogen and of organic carbon (1% total organic carbon (TOC) and 0.058% total nitrogen (TN) in 0.1 M H2SO4). Gas chromatography-mass spectrometry (GC–MS) results clarified the nature of this loss, showing that 54% of ketones and 39% of alcohols were removed when 0.1 M H2SO4 was employed. Furthermore, FT-IR spectra remained the same before and after acid washing without affecting any functional groups. This work therefore proposes demineralization as a viable route for the removal of high inorganic content from lignocellulosic HTL biocrudes.

Adsorption Isotherm of Carbon Microparticles Prepared from Pumpkin (Cucurbita maxima) Seeds for Dye Removal

This study aims to evaluate the adsorption isotherm of carbon microparticles prepared from pumpkin (Cucurbita maxima) seeds for adsorbing curcumin (as a model of dye). The results were derived and compared using the kinetics approach based on several standard adsorption isotherm models, namely the Langmuir, Temkin, Freundlich, and Dubinin-Radushkevich models. The second aim is to evaluate the effects of carbon particle size (from 100 to 1000 mm) on the adsorption characteristics. The experimental results showed that the adsorption on the surface of carbon microparticles occurred in monolayer with a physical phenomenon. This is because the active areas are located only on the outer surface of carbon and no surface structure in the carbon is available. This is confirmed by the fact that the produced carbon has less porosity and the pores themselves are mostly produced from the release of inorganic contents during carbon synthesis, while the amount of inorganic content is very less. The confirmation of the adsorption profile was also achieved by testing various sizes of carbon microparticles. Smaller particles have direct impacts on the improvement of adsorption capacity, which is due to the existence of a larger surface area, a larger number of adsorption sites, and additional cooperative adsorption, i.e. adsorbate-adsorbate interaction. Understanding the adsorption phenomena occurring on carbon particles is useful for further developments and applications, such as those of catalysts and adsorbents, especially concerning the production of carbon materials from organic waste.

Effects on Morphology and Chemical Properties of Indonesian Bamboos by Carbonization

A simple carbonization technique was applied to utilize Indonesian bamboo resources. Several bamboo species as betung (Dendrocalamus asper), andong (Gigantochloa pseudoarundinacea (Steudel) Widjaja), hitam (G. atroviolacea), tali (G. apus), kuning (Bambusa vulgaris var. striata), and ampel bamboo (B. Vulgaris Scharad) were selected for carbonization. Carbonization was conducted using a laboratory electrical furnace at 200, 400, 600, 800, and 1,000 1,000°C. The morphological and chemical properties of bamboos before and after carbonization were then analyzed. Betung, hitam, tali, kuning, and ampel bamboos had type IVstructure which was the most common bamboo structure, while andong bambo had type III structure. Cracks in the fiber bundle were observed and became more visible with the increase of carbonization temperature.The pH showed a similar trend in all species.As a result of the electric conductivity test, carbonized andong and kuning bamboo showed higher value due to rich inorganic content.Kuning bamboo has a high value of potassium and silica content, which are suitable for use as fertilizer.The chemical structure transition of bamboo during the carbonization process was analyzed by FTIR spectroscopy, and significant changes were observed between 400 and 600°C. These results could be useful fundamental data for promoting high value-added bamboo utilization and improving research in Indonesian bamboo.Keywords: bamboo charcoal, carbonization, Indonesian bamboo, inorganic content, FTIR

Proximate Composition of Morning Glory (Ipomea indica) Leaf Meal

Biochemical studies with a view to evaluate the organic and inorganic nutrients in air-dried Ipomea leaf meal commonly known as morning glory (Ipomea indica) was carried out. Samples were replicated four times and the values recorded for each nutrient according to the replicates analyzed. The results of mean percentages for organic nutrients revealed that the samples contained 6.83±0.33% moisture, 6.83±0.17% ash, 17.89±0.45% protein, 1.67±0.17% lipid, 1.84±0.34% fiber and 81.84±0.38% nitrogen free extract (NFE). The inorganic content on the other hand was 0.68±0.04% magnesium, 1.11±0.08% sodium, 3.33±0.56% potassium, 1.68±0.03 calcium and 0.53±0.01% phosphorous. This indicated that air-dried leaf meal from Ipomea indica has nutritional qualities that could provide farmers with organic and inorganic nutrients for enhanced livestock nutrition. Therefore, air-dried leaf meal from Ipomea indica is recommended for feeding livestock in the study area.

Pre-treatments of pre-consumer cotton-based textile waste for production of textile fibres in the cold NaOH(aq) and cellulose carbamate processes

Recycling of textiles is of importance due to the large amount of waste generated from the increasing consumption and use worldwide. Cotton-rich pre-consumer textiles are considered as potential raw material for production of man-made regenerated fibres, but demands purification from the blends with synthetic fibres as well as the dyes and finishing chemicals. In this study we explore the use of different pre-treatments of pre-consumer textiles to meet specific parameters for production of fibres in the cold NaOH(aq) or cellulose carbamate process. The pre-treatments consisted of different bleaching sequences and were performed on both uncoloured and coloured pre-consumer textiles. For the uncoloured textile, degree of polymerisation and amount of inorganic content was efficiently reduced making the material suitable for both the cold NaOH(aq) and the cellulose carbamate process. In case of the coloured textile, the pre-treatments were able to remove the dye and decrease the inorganic content as well as reduce the degree of polymerisation but only sufficiently enough for production of fibres in the cellulose carbamate process. The work was able to prove a fibre-to-fibre concept while further optimisation of the regeneration steps is expected to improve the mechanical properties of the produced fibres in future studies.