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A study was designed to investigate the chemical coagulation process for the treatment of the potato food industry wastewater of the “Chipsy factory” located at Abi‐Sier, Egypt. The chemical coagulants used in the study include alum, ferric chloride, calcium chloride, ferric sulphate and Nalco as polymer. Variable doses of these coagulants were examined to determine the optimum dose. Results obtained showed that chemical treatment (coagulation, flocculation, followed by sedimentation) was efficient to reduce the chemical oxygen demand (COD), total suspended solids (TSS) and turbidity significantly. Remarkable variation of the removal efficiency depends on the type of coagulant. Ferric chloride and ferric sulphate were more efficient than calcium chloride. Combination of Nalco with each of the studied coagulants improved the removal efficiency remarkably. Reduction of 91‐94 per cent of turbidity, 93‐97 per cent of COD, and 94‐97 per cent of the TSS was achieved with these combinations.

The performance of commercial aluminium as a sacrificial anode for cathodic protection of mild steel in 0.3% sodium chloride has been studied in alkaline compositions for anolyte based on slaked lime. The influence of several addition agents has been investigated with a view to suppressing local cell action in the above‐mentioned environment.

The purpose of this study is to explore the feasibility of utilizing agricultural (almond shell, rice husk and wood) waste biochars for partial cement replacement by evaluating the relationships between the physiochemical properties of biochars and the early-age characteristics of cement pastes.

Biochars are prepared through the thermal decomposition of biomass in an inert atmosphere. Using varying percentages, biochars are used to replace ordinary Portland cement (OPC) in cement pastes at a water/binder ratio of 0.35. Characterization methods include XPS, FTIR, SEM, TGA, BET, Raman, loss-on-ignition, setting, compression and water absorption tests.

Accelerated setting in biochar-modified cement pastes is attributed to chemical interactions between surface functional groups of biochars and calcium cations from OPC, leading to the early development of metal carboxylate and alkyne salts, alongside the typical calcium-silicate-hydrate (C-S-H). Also, metal chlorides such as calcium chlorides in biochars contribute to the accelerate setting in pastes. Lower compression strength and higher water absorption result from weakened microstructure due to poor C-S-H development as the high carbon content in biochars reduces water available for optimum C-S-H hydration. Amorphous silica contributes to strength development in pastes through pozzolanic interactions. With its optimal physiochemical properties, rice-husk biochars are best suited for cement replacement.

While biochar parent material properties have an impact on biochar properties, these are not investigated in this study. Additional investigations will be conducted in the future.

Carbon/silicon ratio, oxygen/carbon ratio, alkali and alkaline metal content, chlorine content, carboxylic and alkyne surface functional groups and surface areas of biochars may be used to estimate biochar suitability for cement replacement. Biochars with chlorides and reactive functional groups such as C=C and COOH demonstrate potential for concrete accelerator applications. Such applications will speed up the construction of concrete structures and reduce overall construction time and related costs.

Reductions in OPC production and agricultural waste deterioration will slow down the progression of negative environmental and human health impacts. Also, agricultural, manufacturing and construction employment opportunities will improve the quality of life in agricultural communities.

Empirical findings advance research and practice toward optimum utilization of biomass in cement-based materials.

The specific influence of calcium and sodium cations on the rate of deposition of a‐Fe2O3 (a main corrosion product in boilers and heat exchangers) has been experimentally studied. A deposition model based on the microlayer evaporation and dryout phenomena that occur in the nucleate boiling bubble is put forward for interpretation of the deposited layer. It has been found that the rate of deposition of Fe2O3 increases with the increase in valency of the soluble cations. With calcium, the deposition rate increases linearly with the increase in its ionic concentration, whereby the rate is increased by 5.9, 6.8 and 7.6 with 200, 400 and 600 ppm calcium respectively. Development of the deposition layer takes place in the valleys of the surface contour according to a micro‐layer evaporation mechanism. Successive deposition is performed at the periphery of the first deposit. Reduction in cation content in the crude solution and selecting smooth heated surfaces are recommended to reduce the ∝‐Fe2O3 deposition on heated surfaces in boiling water.

Differences in laws and regulations concerning the compositional requirements for cheese in EEC member states were studied. The parameters examined were authorised basic materials, optional ingredients, food additives and materials not allowed. No substantial differences regarding the basic materials were observed. Differences exist in respect to authorised optional ingredients. With respect to authorised food additives there is a considerable variation in the number of additives allowed in each country, although the additives permitted are, in general, within the list of those approved by the EEC Council. Requirements for treating raw materials and legal provisions for different cheese types were also examined.

The study aims to develop low-sodium chevon patties from low-fat emulsion using various salt substitutes (KCl, CaCl2 and mushroom extract) in different combination without affecting the quality of the products.

Efficacy of salt substitutes was assessed for the development of low-sodium chevon patties. The developed products were assessed for various physicochemical properties, instrumental texture and color profile, estimation of mineral and sensory attributes.

Significant difference (p < 0.05) in mineral content was observed among the patties developed with different salt blends. Sodium content was reduced to the level of 38.07% in salt-substituted chevon patties. Calcium content was significantly (p < 0.05) higher in LS2, LS3 and LS4 salt-substituted chevon patties. Hardness, gumminess and chewiness values were significantly (p < 0.05) higher, and the springiness value was significantly (p < 0.05) lower in control chevon patties compared to treatments. Flavor and saltiness were significantly (p < 0.05) lower in LS1, LS3 and LS4 compared to control. However, flavor, juiciness and saltiness as well overall acceptability scores for LS2 were superior and widely accepted among the sensory panelists.

Based on sensory attributes and physicochemical properties, it is concluded that LS2 salt blend may suitably be used as excellent salt replacer to develop low-sodium chevon patties.

Innovative findings of the experiment strengthen the current literature available on functional animal food products. Further, it provides one of the important natural alternatives to develop low-sodium meat products with special reference to chevon. Looking to increase attention toward health of the consumer and increase in the risk of cardiovascular diseases, the demand of low-sodium products is very high. Therefore, this may be the excellent choice without affecting the quality and sensory attribute of the products.

Although the wind of change is blowing strongly through the gas industry a substantial proportion of the gas, for some time to come, will be made by coal carbonisation and by carburetting water gas. Even these more conventional methods will be subject to change such as the choice of lower‐rank coals to produce reactive smokeless solid fuels and the use of light Hydrocarbon oils, such as primary flash distillate, in place of gas oil. This article deals with some of the corrosion problems that arise in these more established types of plant.

Phosphonic acids are good complexing agents. However, they are not good as inhibitors except for a very few. Synergistic inhibition is offered in the presence of metal cations like Ca²⁺, Mg²⁺, Zn²⁺ and others in neutral media. The zinc ion is an ideal choice. The part of zinc ions are now replaced by polymers, azoles to prepare eco‐friendly inhibitor formulations. They are also used as corrosion inhibitors in concrete, coatings, rubber blends, acid cleaners, anti‐freeze coolants, etc. Discusses the various applications of phosphonic acids and their action mechanisms.

It would be easy to make the general statement that the only major factor an engineer need consider when selecting a pipe‐protection material is that it should resist corrosion. Certainly he must be concerned with electrolytic and galvanic attack, abrasion, chemical action and the effect of weather. This, however, is only part of the story. This article reviews the properties of polyvinyl chloride tapes and the very real part which they, and, in particular Scotchrap PVC tapes, are playing in the prevention of pipeline deterioration.

Other Industrial Gases All oxidising gases can lead to oxide formation on chromium steels at elevated temperatures and in some instances this can be associated with absorption of some other substance in the steel. Carbonaceous gases are a good example and whereas high‐alloy steels successfully resist flue gases even under conditions of considerable air deficiency, reduction of oxygen content eventually leads to conditions under which at a sufficiently high temperature considerable carburisation of the metal occurs. An example is the endothermic gases used as protective atmospheres for other metals which, at elevated temperature, can rapidly cause embrittlement of high‐alloy steel.