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Solutions of the twin plane jets HF chemical laser flow based on a turbulent kinetic theory, due to a modified Green’s function method, are presented. The calculated results of probability density function (PDF) of various chemical species in velocity space, and mass fraction concentration distributions of various reactants and products in the flow field, are revealed and discussed in this analysis. The transport phenomena of different pumping rate, collisional deactivation rate, and radiative deactivation rate in the interaction between the twin plane jets HF chemical laser show that the properties of species mass fraction concentrations, collisional reaction rate, and radiative incident intensity are the dominant factors. The present study provides the fundamentals for theoretical understanding of twin plane jets HF chemical laser and further application to multiple‐jet HF chemical laser analysis.

A citation analysis was conducted on publications of the faculty from the University of Florida (UF), Department of Chemical Engineering. The analysis was undertaken to gain a better understanding of the research programs in chemical engineering and to examine how the library aligns its research support through resources and journals to the needs of the department’s faculty. The analysis focused on where the faculty published, their most frequently cited resources, and what growth patterns were evident. The paper aims to discuss these issues.

Five years of publications (2011-2015) by the UF chemical engineering faculty were included in the analysis. Web of Science was used to compile a list of the articles published in peer-reviewed journals as well as the citations.

Faculty were found to have published 279 articles in the last five years, with 27 percent of those articles shared by five journals, and with an average impact factor of 3.459. Applied Physics Letters was the most cited journal and Advanced Materials had the highest impact factor of 17.493. The library owned 95 percent of the publications in which faculty published their work and at least 82 percent of the resources cited in their publications. The pattern of the publications was not consistent and the most articles in one year (69) were published in 2013.

Since this study focused on the current patterns regarding where the faculty are publishing and citing, it should be a fairly accurate indicator of their future needs. Therefore, the study impacts decisions regarding future directions by enabling the library to maintain a high-quality collection for the faculty.

Biomonitoring uses biological responses to assess environmental changes, which are frequently due to anthropogenic pollution. Biomonitoring can be carried out at different levels of complexity: population, species or suborganismic responses may be used as indicators for exposure to pollutants. In the case of tests with whole organisms, their quality is often impaired by the heterogeneity of living organisms, slow responses and the fact that little information can be provided on the pollutants. Although suborganismic tests can provide more specific and fast responses, structure and concentration of pollutants are only revealed by chemical analysis. A novel approach to biomonitoring is introduced, which applies tight coupling of bioassays and chemical analysis and is defined as bioresponse‐linked instrumental analysis. It combines biomolecular recognition, initiating a biological effect and chemical analysis.

The purpose of this paper is to propose a process management framework for Chemical Waste Treatment Laboratories (CWTL) that can be used as a management tool to identify and manage critical process.

Proposition of a generic classification for categories of chemical waste; use of the ABC analysis as a tool for analysis of priority in relation to the inputs of an CWTL; use of the process matrix (variety vs volume) to identify the key resources required to perform the activities of a CWTL; and use of mapping process techniques to map the processes defined and calculate times.

The proposed framework was applied to a CWTL at University of São Paulo, Brazil, and showed that the high variability of demand is a significant factor in the management of this laboratory, requiring processes that are flexible to meet this demand. The results showed that the applicability of the production and operations management theories within the scope of process management of CWTLs, proved to be useful tools for improving the treatment efficiency of chemical waste in these facilities.

The novelty of this work is in the fact of using production and operations management tools in the management of CWTLs to propose diagnoses to improve the management of their processes. The proposition of a comprehensive classification for chemical wastes generated in CWTLs is also highlighted.

Gourd fibres (GF) are a natural biodegradable fibre material with excellent mechanical properties and high tensile strength. The use of natural fibres in composite materials has gained popularity in recent years due to their various advantages, including renewability, low cost, low density and biodegradability. Gourd fibre is one such natural fibre that has been identified as a potential reinforcement material for composites. However, it has low surface energy and hydrophobic nature, which makes it difficult to bond with matrix materials such as polyester. To overcome this problem, chemically adapted gourd fibre has been proposed as a solution. Chemical treatment is one of the most widely used methods to improve the properties of natural fibres. This research evaluates the feasibility and effectiveness of incorporating chemically adapted gourd fibre into polyester composites for industrial fabrication. The purpose of this study is to examine the application of chemically modified GF in the production of polyester composite engineering materials.

This work aims to evaluate the effectiveness of chemically adapted gourd fibre in improving the adhesion of gourd fibre with polyester resin in composite fabrication by varying the GF from 5 to 20 wt.%. The study involves the preparation of chemically treated gourd fibre through surface modification using sodium hydroxide (NaOH), permanganate (KMnO₄) and acetic acid (CH₃COOH) coupling agents. The mechanical properties of the modified fibre and composites were investigated. It was then characterized using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) to determine the changes in surface morphology and functional groups.

FTIR characterization showed that NaOH treatment caused cellulose depolymerization and caused a significant increase in the hydroxyl and carboxyl groups, showing improved surface functional groups; KMnO₄ treatment oxidized the fibre surface and caused the formation of surface oxide groups; and acetic acid treatment induced changes that primarily affected the ester and hydroxyl groups. SEM study showed that NaOH treatment changed the surface morphology of the gourd fibre, introduced voids and reduced hydrophilic tendencies. The tensile strength of the modified gourd fibres increased progressively as the concentration of the modification chemicals increased compared to the untreated fibres.

This work presents the designed composite with density, mechanical properties and microstructure, showing remarkable improvements in the engineering properties. An 181.5% improvement in tensile strength and a 56.63% increase in flexural strength were got over that of the unreinforced polyester. The findings from this work will contribute to the understanding of the potential of chemically adapted gourd fibre as a reinforcement material for composites and provide insights into the development of sustainable composite materials.

The purpose of this paper is to describe a multi‐robot solution to the problem of chemical source localization, in which a team of inexpensive, simple vehicles with short‐range, low‐power sensing, communication, and processing capabilities trace a chemical plume to its source emitter

The source localization problem is analyzed using computational fluid dynamics simulations of airborne chemical plumes. The analysis is divided into two parts consisting of two large experiments each: the first part focuses on the issues of collaborative control, and the second part demonstrates how task performance is affected by the number of collaborating robots. Each experiment tests a key aspect of the problem, e.g. effects of obstacles, and defines performance metrics that help capture important characteristics of each solution.

The new empirical simulations confirmed previous theoretical predictions: a physics‐based approach is more effective than the biologically inspired methods in meeting the objectives of the plume‐tracing mission. This gain in performance is consistent across a variety of plume and environmental conditions. This work shows that high success rate can be achieved by robots using strictly local information and a fully decentralized, fault‐tolerant, and reactive control algorithm.

This is the first paper to compare a physics‐based approach against the leading alternatives for chemical plume tracing under a wide variety of fluid conditions and performance metrics. This is also the first presentation of the algorithms showing the specific mechanisms employed to achieve superior performance, including the underlying fluid and other physics principles and their numerical implementation, and the mechanisms that allow the practitioner to duplicate the outstanding performance of this approach under conditions of many robots navigating through obstacle‐dense environments.

The complexity in determining the quality of a credence good like wine increases due to the lack of mandatory ingredient labeling. This has generated a significant information asymmetry in the wine market, leading consumers to delegate their purchase decisions to expert rankings and wine guides. This paper explores whether expert assessments reduce the information asymmetry caused by the absence of ingredient labeling in the wine market.

By employing analysis of variance (ANOVA) in a sample of 304 wines included in the Wine Guide of the Spanish Consumers Organization (OCU), this paper assesses the extent to which expert assessments based on sensory evaluations converge with the objective cues provided by laboratory analysis in wine quality evaluations.

Results reveal a mismatch between expert assessments and laboratory analyses. Chemical aspects such as SO₂ levels or volatile acidity, sensorial factors such as intensity and persistence, and extrinsic variables such as the region of origin or wine type play an important role in the quality ranking of wines.

These findings call for the inclusion of objective intrinsic cues in expert sensory assessments to provide consumers reliable information about wines and to resolve the apparent dissonances in wine quality assessments.

The purpose of this paper is to make a lean assessment of a chemical analyst training laboratory in a higher education institution and identify the main types of waste on a daily basis and understand the lean maturity of the laboratory and establish priority areas of intervention to make the laboratory leanest.

A single descriptive case study methodology was used to carry out the lean laboratory evaluation. The lean manufacturing waste terminology was adapted to a lean analytical laboratory environment, and a lean waste assessment step-by-step procedure was developed to reach the study goal.

Three types of waste (i.e. transport, waiting and defects) were the main contributors of the problem. The Pareto analysis results showed that 37.5% of the different types of waste contributed to almost 51.4% of the problems. The case study allowed on diagnosing wastes, understanding the lean maturity in a teaching laboratory setting and priority areas of intervention

Some data collection methods were used, and tools were developed to answer the research questions. A waste measurement instrument was created to evaluate lean waste in a chemical analytical laboratory, and a lean classification scheme was built to understand the lean maturity of the laboratory. The lessons learnt of the lean assessment in a teaching laboratory and the developed tools will be helpful for future research and for practitioners in a teaching chemical analytical laboratory setting.

The number of lean assessment studies in teaching laboratories is not very significant, and this work contributes to overcome this gap illustrating the lean waste assessment foundation with a step-by-step procedure and tools used in a teaching laboratory to perform a lean assessment and identify opportunities for improvement. A generic roadmap to lean laboratory waste assessment and continuous improvement is proposed with the key elements to take into consideration.

Introduces some simple statistics employed in analysing chemical analysis data. Describes measures of precision and accuracy and how the use of confidence intervals and repeatability can guide validation of data.

The purpose of this paper is to substitute wheat flour by passion fruit peel flour in Brazilian honey bread (pão de mel), with evaluation of the breads’ sensory features, chemical composition and physical properties.

Honey breads with wheat flour (standard) and with replacement of this ingredient by 10 to 50 per cent passion fruit peel flour were produced. Two sensory tests were applied, to identify how different formulations with passion fruit peel flour were when compared to the standard formulation, and also the acceptability of the products. The selected honey breads, through sensory results, were evaluated regarding to chemical composition and physical properties.

Formulations with 10 and 20 per cent substitution were the least different to formulations with only wheat flour, and were as acceptable as the wheat flour sample. Physical and chemical characteristics of breads with 10 and 20 per cent passion fruit peel flour were similar; however, honey bread with 20 per cent passion fruit peel flour had higher fibre content, ash quantity and hardness value; a lower specific volume; and a different colour from the wheat flour sample.

This study offers an opportunity to food industries through utilization of an agro-industrial by-product on the formulation of a Brazilian traditional product.

This study presents the feasibility of using an agro-industrial by-product to Brazilian honey bread, enhancing the nutritive value of this product and reducing the impact of passion fruit peel flour on the environment.