The triplet “molecular processes–product–process” engineering: the future of chemical engineering ?

Today chemical engineering has to answer to the changing needs of the chemical and related process industries and to meet the market demands. Being a key to survival in globalization of trade and competition, the evolution of chemical engineering is thus necessary. Its ability to cope with the scientific and technological problems encountered will be appraised in this paper. To satisfy both the markets requirements for specific end-use properties of products and the social and environmental constraints of the industrial-scale processes, it is shown that a necessary progress is coming via a multidisciplinary and a time and length multiscale approach. This will be obtained due to breakthroughs in molecular modelling, scientific instrumentation and related signal processing and powerful computational tools. For the future of chemical engineering four main objectives are concerned: (a) to increase productivity and selectivity through intelligent operations via intensification and multiscale control of processes; (b) to design novel equipment based on scientific principles and new methods of production: process intensification; (c) to extend chemical engineering methodology to product focussed engineering, i.e. manufacturing and synthesizing end-use properties required by the customer, which needs a triplet “molecular processes–product–process” engineering; (d) to implement multiscale application of computational chemical engineering modelling and simulation to real-life situations, from the molecular scale to the overall complex production scale.     

Students’ performance and perceptions on continuous assessment. Redefining a chemical engineering subject in the European higher education area

Chemical Engineering taught as a subject across three Energy Engineering-based degree streams was evaluated considering two cohorts in two consecutive years after the implementation of the Bologna Process in Spain. A regular continuous assessment methodology yielded negative results during the first year. Student insight on course development, own expectations and results, and the evaluation system were then explored via a 33-item survey with participation levels between 41% and 82%. Direct answers were evaluated including rank correlations between all items. The 465 correlation coefficients obtained showed stimulating and unanticipated results. For example, it was shown that a severe grading process (external blame-assignment) was only identified as an explanation for a low mark by those students who performed most poorly in the subject and, therefore, had a poorer understanding of the materials.Besides, the feedback received from students was used to implement several changes in both the teaching practice and the assessment method during the second year, such as incorporating exam-like problems in daily classes and setting two midterm exams instead of the final one. The results registered after the second year pointed to substantial progress in student learning. Pass rates also rose from a 30% in the first academic year to 49% and 58% in the two following ones.     

Dilemmas in the reliable estimation of the in-vitro cell viability in magnetic nanoparticle engineering: which tests and what protocols?

Magnetic nanoparticles [MNPs] made from iron oxides have many applications in biomedicine. Full understanding of the interactions between MNPs and mammalian cells is a critical issue for their applications. In this study, MNPs were coated with poly(ethylenimine) [MNP-PEI] and poly(ethylene glycol) [MNP-PEI-PEG] to provide a subtle difference in their surface charge and their cytotoxicity which were analysed by three standard cell viability assays: 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium [MTS], CellTiter-Blue and CellTiter-Glo (Promega, Southampton, UK) in SH-SY5Y and RAW 264.7 cells The data were validated by traditional trypan blue exclusion. In comparison to trypan blue manual counting, the MTS and Titer-Blue assays appeared to have consistently overestimated the viability. The Titer-Glo also experienced a small overestimation. We hypothesise that interactions were occurring between the assay systems and the nanoparticles, resulting in incorrect cell viability evaluation. To further understand the cytotoxic effect of the nanoparticles on these cells, reactive oxygen species production, lipid peroxidation and cell membrane integrity were investigated. After pegylation, the MNP-PEI-PEG possessed a lower positive surface charge and exhibited much improved biocompatibility compared to MNP-PEI, as demonstrated not only by a higher cell viability, but also by a markedly reduced oxidative stress and cell membrane damage. These findings highlight the importance of assay selection and of dissection of different cellular responses in in-vitro characterisation of nanostructures.     

HCBS ceramic concretes in the XXI century — problems and prospects for applying technology in the field of silicate materials science. Part 1

In the technology of a number of ceramic and refractory materials, prepared on the basis of highly concentrated ceramic binder suspensions (HCBS), elements of effective nanotechnology were realized even before the present “nanoboom.” The concept has been formulated of an advance in materials technology based on HCBS both in traditional fields of their application, and in the field of structural materials science, within which for industrial introduction of existing developments it is necessary to create contemporary equipment formulation for production processes.     

Textile research and development in the UK – success or failure?

Although initially lagging behind the USA, the amount and quality of research and development carried out in the UK can be compared favourably with that from other major world countries. The industrial research association, although a well‐conceived concept to increase research and development efforts that gave significant results, was disappointing for several reasons. A major problem has been the dissemination, exploitation and commercialisation of research results. The activities of research organisations need to be reviewed regularly, as they may have a relatively short lifespan. The intermediate research and technology sector, given adequate support, may be the vehicle for better utilisation of research and development results.     

HSG400 – Design,implementation, and evaluation of a hybrid board game for aiding chemistry and chemical engineering students in the review of stereochemistry during and after the COVID-19 pandemic

This paper provides information about a hybrid multilingual (English, Portuguese, French, and Italian) game developed as an alternative learning method to the traditional problem-solving exercises model. The game comprises a physical board and a free-of-charge application for undergraduate students to review and reinforce concepts related to stereochemistry by answering questions, from a bank of 400 questions, in a ludic, competitive, and collaborative environment. Brazilian, French, and Italian undergraduate students played the game face-to-face before the disruption caused by the Covid-19 Pandemic and remotely during that. They also evaluated the game, and the quite positive results obtained from students’ self-assessment revealed that they felt the game contributed to their learning while playing.     

Determining the cause-and-effect relationships responsible for coal properties. 3. Association of chemical elements and role of indicators and accompanying elements in assessing the variability of beds’ mineral composition

In the development of productive coal and oil beds, certain geochemical conditions facilitate the formation of elementary associations that include indicator elements and accompanying elements. The determination of those associations permits the identification of the features of mineral formation in the beds and the processes that affect the variability of the mineral composition in the intervening rock.     

Growth Factors,Reactive Oxygen Species,and Metformin—Promoters of the Wound Healing Process in Burns?

Burns can be caused by various factors and have an increased risk of infection that can seriously delay the wound healing process. Chronic wounds caused by burns represent a major health problem. Wound healing is a complex process, orchestrated by cytokines, growth factors, prostaglandins, free radicals, clotting factors, and nitric oxide. Growth factors released during this process are involved in cell growth, proliferation, migration, and differentiation. Reactive oxygen species are released in acute and chronic burn injuries and play key roles in healing and regeneration. The main aim of this review is to present the roles of growth factors, reactive oxygen species, and metformin in the healing process of burn injuries.     

Adhere to the principle of “Science and technology is the No. 1 productive force”, strive for the realization of the strategic target of“Boosting chemical industry by science and technology”

In this pen conference, we have invited authorities and experts concerned to further elaborate the connotations and significance of the principle of "Science and technology is the No. 1 productive force" , discuss the problems encountered in implementing the principle in chemical industry and measures consequently taken against them and exchange experience gained in executing the policy of "Boosting chemical industry by science and technology" , The purpose is to accelerate the modernization process of China's chemical industry and realize the strategic target set by the government.     

Oxidation of Herbicides in Groundwater by the Fenton Process: A Realistic Alternative for O3/H2O2 Treatment?

Oxidation with O₃/H₂O₂ and Fe²⁺/H₂O₂ are optional for the degradation of herbicides and pesticides in water. The choice of which process will be applied depends upon the degree of degradation of organic micropollutants and the process conditions related to the formation of oxidation by-products, and also on the total costs and the safety and reliability of the process. Under real conditions, atrazine and some phenylureaherbicides were oxidized with O₃/H₂O₂. Comparable experiments under conditions of different pH, iron and DOC content were performed with Fe²⁺/H₂O₂, in order to gain information on the influence of these parameters. The oxidation results of both processes as well as the formation of bromate as one of the oxidation by-products are described. It was found that 80% of atrazine and >99% of some phenylureaherbicides could be degraded with O₃/H₂O₂ at pH 7.8 (H₂O₂/O₃ ratio 3.7 g/g). Under these conditions, bromate was formed up to 5 μg/1. Comparable results were obtained with Fe²⁺/H₂O₂ at a pH value of 5.5, whereas the formation of bromate was kept below 0.2 μg/L.     

How much nitrogen is fixed by biological symbiosis in tropical dry forests? 1. Trees and shrubs

Despite the recognized importance of the process, estimates of the amount of nitrogen fixed by biological symbiosis in tropical dry forests are almost nonexistent. We estimated the nitrogen fixed annually by the leaves of trees and shrubs at sites regenerating for 16 and 38?years and in an old-growth dry forest using ¹⁵N abundance methodology. The total leaf biomass (1,824?C3,036?kg?ha^?1) and nitrogen contents (62?C90?kg?ha^?1) did not differ among the areas. In all of the areas, most of the leaf biomass belonged to legume plants, but the proportion of the N₂-fixing legumes decreased with increasing regeneration time. In the 16-year regenerating area, almost all of the N was in the leaves of the N-fixing Mimosa tenuiflora plants, but fixation was absent or very low as it was in the N-fixing species present in the 38-year regenerating area. In the old-growth Caatinga, all of the N-fixing species (M. tenuiflora, Piptadenia stipulacea and Anadenanthera colubrina) had large proportions (47?C62?%) of their N derived from atmospheric N₂, but the amount of fixed N (6?kg?ha^?1) was a small proportion of the total leaf N because these plant species were a small part of the vegetation. The total input of biologically fixed N to the old-growth forest was similar in magnitude to an estimate made for a humid tropical forest in Amazonia.     

Urban Outdoor?Indoor PM2.5 Concentrations and Personal Exposure in the Deep South. Part II. Inorganic Chemistry

Abstract

This paper reports the results of an exploratory inorganic chemical characterization of PM_{2 . 5}. The particle samples exemplify the personal exposure of nine healthy, nonsmoking individuals living and working in the metropolitan area of Birmingham, Alabama, in comparison with stationary outdoor and indoor sampling at their homes. The samples were taken by filtration in two seasons, summer and winter of 1997?1998. The chemical analyses were performed on water soluble extracts for sulfate, nitrate, ammonium, chloride, and potassium and x-ray fluorescence spectroscopy for elements of atomic number > 13. The results indicate that a sulfate mixture, calculated to be either ammonium sulfate or letovicite, dominated the mass concentration of all samples. Small contributions also derived from nitrate as ammonium nitrate, chloride, aluminum silicates, and metals such as iron, copper, and zinc. Potentially toxic elements such as chromium, nickel, arsenic, and selenium were present only at the ng/m3 level or less. Most of the unaccounted for mass fraction is hypothesized to be carbonaceous material. Correlation was found between sulfate concentration data from outdoor, indoor, and personal samples. Sulfate concentrations also correlated with outdoor PM_{2 . 5} gravimetric mass concentrations. However, minor or trace contaminant concentrations were not correlated with outdoor mass concentrations. Indoor sulfate levels can be explained by infiltration of outdoor particles into the buildings, while evidence was found for sources of PM_{2 . 5} particles indoors in four of eight residences in summer and two of eight in winter.