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1 – 10 of 606PART IV Inorganic chemistry textbooks. Seventeen textbooks of inorganic chemistry are considered in this part of the review, and the inorganic sections of the syllabuses…
Abstract
PART IV Inorganic chemistry textbooks. Seventeen textbooks of inorganic chemistry are considered in this part of the review, and the inorganic sections of the syllabuses of the three GCE Boards previously discussed are analysed.
Nineteen children in every hundred study chemistry to Ordinary Level GCE, and eighty per cent then drop the subject. Judging by current textbooks and examination…
Abstract
Nineteen children in every hundred study chemistry to Ordinary Level GCE, and eighty per cent then drop the subject. Judging by current textbooks and examination syllabuses, these children will have no general understanding of modern chemistry. The author puts forward some suggestions for modernising chemistry curricula.
Navnidhi Chhikara, Burale Abdulahi, Claudia Munezero, Ravinder Kaur, Gurpreet Singh and Anil Panghal
Sorghum is quite comparable to wheat, rich source of nutrients with various health benefits, and therefore considered as a grain of future. The purpose of this paper is to…
Abstract
Purpose
Sorghum is quite comparable to wheat, rich source of nutrients with various health benefits, and therefore considered as a grain of future. The purpose of this paper is to review the bioactive active compounds, health benefits and processing of the sorghum. Sorghum is utilized for animal feeding rather than the human food usage. Therefore, this paper focuses on the emerging new health foods with benefits of the sorghum.
Design/methodology/approach
Major well-known bibliometric information sources searched were the Web of Science, Google Scholar, Scopus and PubMed. Several keywords like nutritional value of sorghum, bioactive compounds present in sorghum, health benefits of sorghum and processing of sorghum were chosen to obtain a large range of papers to be analyzed. A final inventory of 91 scientific sources was made after sorting and classifying them according to different criteria based on topic, academic field country of origin and year of publication.
Findings
From the literature reviewed, sorghum processing through various methods, including milling, malting, fermentation and blanching, bioactive compounds, as well as health benefits of sorghum were found and discussed.
Originality/value
Through this paper, possible processing methods and health benefits of sorghum are discussed after detailed studies of literature from journal articles.
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A.A. Al‐Suhybani and I.H. Al‐Hwaidi
Introduction The corrosion of iron has been extensively studied in various media. In nitric acid solutions, the corrosion of iron is much faster than in other mineral…
Abstract
Introduction The corrosion of iron has been extensively studied in various media. In nitric acid solutions, the corrosion of iron is much faster than in other mineral acids at comparable concentrations. This is attributed to an autocatalytic process involving some nitrogen oxides, nitrous acid and/or some iron complexes. At high nitric acid concentrations, passivation of iron takes place. The factors affecting the dissolution and the passivation processes are not fully understood. The effect of various inhibitors on the corrosion of iron in acid media has been studied. Thus Ammar et al. have studied the passivation of iron and the effect of some anions, e.g. Br− and I− on the passive film. The effect of amides as inhibitors for iron in nitric acid has been reported by Fouda and Gouda. These authors have found that the corrosion process is controlled by the reaction of amides with HNO3 and not by the surface reaction. The effect of aniline and some aminobenzoic acids on the rate of corrosion of iron has been reported. The present work is aimed at examining the efficiencies of some aniline substitutes as corrosion inhibitors for the corrosion of iron in concentrated nitric acid solution.
Stainless steel pickling is a major generator of NOx emissions and is also a major producer of nitrate effluents. Hydrogen peroxide technologies have been developed and…
Abstract
Stainless steel pickling is a major generator of NOx emissions and is also a major producer of nitrate effluents. Hydrogen peroxide technologies have been developed and proven to suppress NOx emissions and also to replace nitric acid in the pickling process and hence remove the problem of nitrate effluent discharge. Presents case histories to illustrate the effectiveness of hydrogen peroxide both for NOx suppression and for nitric acid‐free pickling when pickling stainless steels.
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Banu Poobalan, Jeong Hyun Moon, Sang-Cheol Kim, Sung-Jae Joo, Wook Bahng, In Ho Kang, Nam-Kyun Kim and Kuan Yew Cheong
The high density of defects mainly attributed to the presence of silicon oxycarbides, residual C clusters, Si- and C-dangling bonds at or near the SiO2/SiC interface…
Abstract
Purpose
The high density of defects mainly attributed to the presence of silicon oxycarbides, residual C clusters, Si- and C-dangling bonds at or near the SiO2/SiC interface degrades the performance of metal-oxide-semiconductor (MOS) devices. In the effort of further improving the quality and enhancement of the SiC oxides thickness, post-oxidation annealed by a combination of nitric acid (HNO3) and water (H2O) vapor technique on thermally grown wet-oxides is introduced in this work. The paper aims to discuss these issues.
Design/methodology/approach
A new technique of post-oxidation annealing (POA) on wet-oxidized n-type 4H-SiC in a combination of HNO3 and H2O vapor at various heating temperatures (70°C, 90°C and 110°C) of HNO3 solution has been introduced in this work.
Findings
It has been revealed that the samples annealed in HNO3 + H2O vapour ambient by various heating temperatures of HNO3 solution; particularly at 110°C is able to produce oxide with lower interface-state density and higher breakdown voltage as compared to wet-oxidized sample annealed in N2 ambient. The substrate properties upon oxide removal show surface roughness reduces as the heating temperature of HNO3 solution increases, which is mainly attributed due to the significant reduction of carbon content at the SiC/SiO2 interface by C=N passivation and CO or CO2 out-diffusion.
Originality/value
Despite being as a strong oxidizing agent, vaporized HNO3 can also be utilized as nitridation and hydrogen passivation agent in high temperature thermal oxidation ambient and these advantages were demonstrated in 4H-SiC.
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Pernille Seljom and Eva Rosenberg
The aim of this paper is to provide a general overview of the global oil and natural gas resources, production, technology development, energy use, emissions and costs…
Abstract
Purpose
The aim of this paper is to provide a general overview of the global oil and natural gas resources, production, technology development, energy use, emissions and costs. The activity is based on the European project “Risk of Energy Availability: Common Corridors for Europe Supply Security” (REACCESS) and the data collected was used in this project as an input to evaluate the technical, economical and environmental characteristics of the energy corridors to European Union (EU).
Design/methodology/approach
The paper is based on literature reviews and data collection from national authorities, oil companies, international associations and international organisations.
Findings
The work provides a general overview of oil and natural gas resources, production rates, recent technology developments, costs, losses, energy consumption and emissions on a world regional level. Main issues related to the role of conventional oil and natural gas in the energy import framework are summarised in this paper.
Research limitations/implications
The present study provides information on conventional oil and natural gas resources and it is limited to primary production technologies.
Originality/value
An outline of oil and natural gas on a regional level is presented. The paper provides general introduction to the subject and it is a valuable input for modelling and analyses of conventional oil and natural gas in the present and in the future energy system.
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Wenjian Wang, Zongben Xu and Jane Weizhen Lu
Artificial neural networks (ANN) are appearing as alternatives to traditional statistical modeling techniques in many scientific disciplines. However, the inherent…
Abstract
Artificial neural networks (ANN) are appearing as alternatives to traditional statistical modeling techniques in many scientific disciplines. However, the inherent drawbacks of neural networks such as topology specification, undue training expense, local minima and training unpredictability will overlay their merits in engineering applications, especially. In this paper, adaptive radial basis function (ARBF) network and improved support vector machine (SVM) are presented in atmospheric sciences. The principle component analysis (PCA) technique is employed to the ARBF network as well, namely, ARBF/PCA network for the convenience of expression and comparison, so as to fasten the learning process. Comparing with traditional neural network models, the proposed models can automatically determine the size of network and parameters, fasten the learning process and achieve good generalization performances in prediction of pollutant level. The simulation results based on a real‐world data set demonstrate the effectiveness and robustness of the proposed methods.
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Sherazed Hamza‐Reguig, Sabrine Louala, Ahmed Boualga and Myriem Y Lamri‐Senhadji
The purpose of this paper was to evaluate the effect of sardine protein on the redox status in rats fed a cholesterol‐rich diet.
Abstract
Purpose
The purpose of this paper was to evaluate the effect of sardine protein on the redox status in rats fed a cholesterol‐rich diet.
Design/methodology/approach
Hypercholesterolemic rats were divided into two groups fed diets enriched with cholesterol and containing 20 percent of sardine proteins (SPc) or casein (CASc) for 28 days. A control group was fed a standard diet (CAS).
Findings
After 28 days of experiment, no significant difference in serum total cholesterol triacylglycerols and uric acid was found with the three diets. Serum albumin content was, respectively, 2‐fold higher in SPc than those in CASc group. Compared to CAS, this value was 1.3‐fold lower in CASc group. In liver and heart, lipid peroxidation was 1.7‐ and 2‐fold lower in SPc compared with CASc and CAS, respectively. In red blood cells and epididymal fat, superoxide dismutase activity was, respectively, 1.3‐and 3‐fold higher in SPc compared to CASc. Epididymal fat and heart catalase activity were, respectively, elevated (+50 and +79 percent) in SPc than in CASc. Sardine protein decreased nitric oxide levels in heart and epididymal fat (twofold) compared to CASc but compared to control group, nitric oxide value was higher in epididymal fat (2‐fold) and liver (3‐fold).
Originality/value
Sardine protein exerts a beneficial action against oxidative stress caused by dietary cholesterol specifically in the heart by reducing lipid peroxidation and enhancing catalase activity.
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J.F. Dallemand, G. De Santi, A. Leip, D. Baxter, N. Rettenmaier and H. Ossenbrink
The objective of this paper is to discuss some scientific challenges related to the production and use of biomass for transport, heat and electricity.
Abstract
Purpose
The objective of this paper is to discuss some scientific challenges related to the production and use of biomass for transport, heat and electricity.
Design/methodology/approach
Specific attention is paid to the environmental assessment of liquid bio‐fuels for transport and to the discussion of causes of uncertainties in the assessment. Three main topics are taken as examples, in order to illustrate the complexity of environmental assessment of bio‐fuels and the difficulty in reducing uncertainties: agro‐environmental impact of bio‐ethanol (from sugar cane) in Brazil and bio‐diesel (from palm oil) in Malaysia. These two tropical countries were selected because of their role as leaders at world level and their strong export potential to the European Union), N2O (Nitrous Oxide) emissions related to crop cultivation for bio‐fuels and land use change; and GHG emissions and Life Cycle Assessment (LCA) of bio‐diesel from palm oil in Malaysia. These three topics are discussed and complemented by considerations about biomass conversion issues.
Findings
The quantification of the degree of the sustainability of the production and use of bio‐fuels for transport is to a large extent related to the choice of farming practices during the feedstock production and their corresponding environmental impact.
Practical implications
Recommendations are formulated so as to reduce scientific uncertainty, for example through the development of internationally‐agreed sustainability certification systems with corresponding verification measures, or further research on emissions and indirect land‐use change.
Originality/value
The value of the paper on bio‐energy research challenges is related to the combined analysis of European and tropical constraints in the field of biomass.
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