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Background: Struvite, biochar and ash products (collectively known as STRUBIAS) derived from different waste streams are used as fertilisers in agriculture. Raw dairy processing sludge (DPS) shows promise as bio‐based fertilisers, but secondary STRUBIAS‐derived products need further testing as fertilisers. Aims: The objective of this study was to calculate the phosphorus mineral fertiliser equivalency (P‐MFE) for some STRUBIAS products derived from DPS. Methods: Ryegrass (Lolium perenne L.) and wheat (Triticum aestivum) pot trials were used to determine the P‐MFE using the apparent P recovery (APR) method for Fe‐DPS and DPS‐derived struvites (Struvite 1–4), hydrochars (HC1–3) and ash. Results: The tested STRUBIAS products can be divided into two groups: (1) a range of products that can (i.e. Struvite 1–3) and (2) cannot (i.e., Struvite 4, HC1–3, ash and Fe‐DPS) be considered fertilisers. In the first group, the P‐MFE ranged from 66.8% to 76.7% for ryegrass and from 77.9% to 93.5% for spring wheat grain. In the second group, the P‐MFE ranged from 7.8% to 58.3% for ryegrass and from −34.5% to −151.3% for spring wheat grain. The negative agronomic effects of some products for wheat grain (struvite and HC) in this study were mainly caused by high Fe content, which could be overcome by improved treatment processes. Conclusions: Future policy and research must be aware that not all the DPS‐derived STRUBIAS products are suitable as fertilisers and therefore need to be tested individually. [ABSTRACT FROM AUTHOR]

Life cycle thinking analysis (LCT) was conducted on the production of vanillin via bamboo wet air oxidation compared to vanillin production from crude oil or Kraft lignin. Synthetic vanillin has been produced from crude oil and paper pulping process "waste" for nearly a century. Bamboo is a quick growing, lignin rich biomass with the potential for the generation of aromatic products including vanillin. Wet air oxidation experiments were performed, using CuSO4 and Fe2O3 catalysts in alkaine environments, on raw bamboo with the purpose of determining the aromatic compound yields in order to investigate bamboo as a potential source of fine chemical products. From the LCT approach, production of vanillin from Kraft Lignin compared to crude oil has a lower environmental impact across all categories per kg produced of vanillin. Kraft lignin production of vanillin is shown to reduce smog formation and CO2 emissions from non energy sources to negligible levels while decreasing acidification potential by 6.8 times, toxic inhalation by 1.3 times and toxic ingestion potential by 0.3 times compared to crude oil. The proposed bamboo oxidation route has the potential to have the least environmental impact with negligible impact on smog formation potential and ozone depletion potential if a green polar extractive solvent can be utilised in future while also decreasing toxicity by inhalation by a further 115 fold and ingestion by 9458 fold. This work has the potential to contribute to the United Nation Sustainable Development Goal for Responsible Consumption and Production, Goal 12. [ABSTRACT FROM AUTHOR]

• This study deals with a biorefinery strategy for manufacturing "platform chemicals". • Soluble hemicellulose derived saccharides are manufactured from Miscanthus by hydrothermal processing. • Furfural is obtained by hydrolysis-dehydration of hemicellulosic saccharides. • Hexoses are obtained by enzymatic processing of the solids previously subjected to autohydrolysis. • The suitability of glucose and fructose as substrates for HMF manufacture are also considered. A biorefinery scheme was proposed for manufacturing platform chemicals (furfural, denoted F, and 5-hydroxymethylfurfural, denoted HMF) from Miscanthus polysaccharides (including hemicelluloses and cellulose). The feedstock was first subjected to hydrothermal processing, which caused an extensive hemicellulose solubilization, yielding solids enriched in cellulose and aqueous solutions rich in saccharides. The acidic processing of the aqueous solutions in the presence of methyl isobutyl ketone (MIBK), which acted as an extracting agent, led to the formation and the in situ separation of F from pentoses at high molar yields (up to 78%). Moreover, HMF and levulinic acid were obtained from the hexoses released from the feedstock. The cellulose-enriched solids from hydrothermal processing were used as a substrate for HMF manufacture, employing a combination of enzymatic and chemical treatments. The enzymatic hydrolysis yielded glucose (in concentration up to 59 g /L), which was enzymatically isomerized into fructose in the presence of sodium tetraborate at yields up to 80%. Acidic treatments of the resulting reaction media at low temperature (134 °C) in the presence of H 2 SO 4 enabled the formation of HMF at yields about 49%. Under the assayed conditions, glucose remained practically unaltered, facilitating its reutilization in the isomerization stage. [ABSTRACT FROM AUTHOR]

Designing and evaluating teacher development programs for graduate teaching assistants (GTAs) who teach in the laboratory is a prominent feature of chemistry education research. However, few studies have investigated the impact of a GTA teacher development program on the verbal interactions between participating GTAs and students in the undergraduate laboratory. Further, little research has been devoted to the development of an instructional model designed specifically for GTAs. This research set out to develop an instructional model to underpin a GTA teacher development program and to evaluate its impact on the cognitive and psychomotor verbal interactions between GTAs and students in the laboratory. Seven GTAs participated in the Teaching as a Chemistry Laboratory Graduate Teaching Assistant (TCL-GTA) program that featured the development and implementation of the Meaningful Learning in the Laboratory (MLL) instructional model seeking to nurture undergraduate students' cognitive, psychomotor, and affective domains of learning. The verbal interactions between each GTA and the students they interacted with were audio recorded for the entire duration of general chemistry laboratory sessions that took place before, during, and after the TCL-GTA program. The purpose of this article is to explore the influence of the TCL-GTA program on the cognitive and psychomotor verbal interactions between GTAs and undergraduate students during general chemistry laboratory sessions. [ABSTRACT FROM AUTHOR]

Throughout countries such as Ireland, the U.K., and Australia, graduate students who fulfill teaching roles in the undergraduate laboratory are often referred to as "laboratory demonstrators". The laboratory demonstrator (LD) model of graduate teaching is similar to the more commonly known graduate teaching assistant (GTA) model that is prevalent in the United States. While the responsibilities of LDs and GTAs in the undergraduate laboratory are similar, both cohorts experience different recruitment and training processes that can influence their teaching behaviors. With respect to enhancing the teaching capability of GTAs, considerable research has investigated the design, implementation, and evaluation of various GTA teacher development programs as well as identified various factors that influence their teaching behaviors. However, there has been relatively less research devoted to enhancing the teaching capability of LDs. This research study set out to inform the design of a teacher development program for graduate students who fulfill LD roles. This study involved the collection of both quantitative and qualitative data as a means of comparing LDs (N = 28) and undergraduate students' (N = 224) perceptions of LDs' responsibilities in addressing cognitive, affective, and psychomotor learning experiences in the noninquiry general chemistry laboratory. In catering to the misalignment of perceived LD responsibilities, this research offers faculty the evidence-align-develop framework that can inform the design of a teacher development program for LDs. Given the similarities between LDs and GTAs with respect to their status as graduate students, their relative experience in learning chemistry, as well as their role in the laboratory, this framework can also inform the design of GTA teacher development programs. [ABSTRACT FROM AUTHOR]

The catalytic properties of 1 wt % Ru catalysts with the same mean Ru cluster size of 1.4-1.5 nm supported on herringbone-type carbon nanofibers with different N contents were compared for H2 production from formic acid decomposition. The Ru catalyst on the support with 6.8 wt % N gave a 1.5-2 times higher activity for the dehydrogenation reaction (CO2, H2) than the catalyst on the undoped support. The activity in the dehydration reaction (CO, H2O) was the same. As a result, the selectivity to H2 increased significantly from 83 to 92 % with N-doping, and the activation energies for both reactions were close (55-58 kJ mol−1). The improvement could be explained by the presence of Ru clusters stabilized by pyridinic N located on the open edges of the external surface of the carbon nanofibers. This N may activate formic acid by the formation of an adduct (>NH+HCOO−) followed by its dehydrogenation on the adjacent Ru clusters. [ABSTRACT FROM AUTHOR]

This study investigated the fractionation of biomass using a decomposing mixture of hydrogen peroxide-formic acid as a pretreatment for the biorefining of Miscanthus x giganteus and of sugarcane bagasse. The main parameters investigated were the hydrogen peroxide concentration (2.5, 5.0 and 7.5 wt%) and biomass loading (5.0 and 10.0 wt%). At the highest hydrogen peroxide concentration used (7.5 wt%), the energy released by the decomposition of the H2O2 could heat the reaction mixture up to 180 °C in a short time (6-16 min). As a result, highly delignified pulps, with lignin removal as high as 92 wt%, were obtained. This delignification process also solubilised a significant amount of pentosan (82-98 wt%) from the initial biomass feedstock, and the resulting pulp had a high cellulosic content (92 wt%). The biomass loading only affected the reaction rate of hydrogen peroxide decomposition. Various analytical methods, including Fourier transform infrared spectroscopy, and thermogravimetric and elemental analyses, characterized the lignin obtained. [ABSTRACT FROM AUTHOR]