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Water soluble epoxy resins were prepared from male‐opimaric acid, linseed fatty acids and epoxy resin. The methylated urea formaldehyde resin and melamine formaldehyde resin were also prepared for curing purposes. The pigmented coating compositions were prepared from water soluble epoxy resins, red oxide and iron and zinc phosphate. These coating compositions showed good water resistance, acid resistance, alkali resistance and lubricating oil resistance.

The purpose of this paper is to investigate an adhesive prepared from soy flour (SF) modified with urea, citric acid and boric acid as an environmentally friendly product for the wood industry.

Urea solution was prepared at 30°C and then SF was added and stirred at 30°C for 2 hours. Citric acid solution was added and stirred for another 0.5 hours and then boric acid solution was added and heated at 30°C for a further 0.5 hours. The resulting adhesive was used to bond poplar veneers. Shear strength was measured to evaluate the bonding property of the adhesive. Viscometry and FT‐IR spectrometry were used to test the viscosity and chemical changes, respectively.

Soy protein has potential value in the preparation of adhesives because of its unique functional characteristics. The optimum formulation was 100 g of soy powder treated with 9 g of citric acid at 30°C for 0.5 hours in the presence of sodium dihydrogen phosphate (NaH₂PO₄). After addition of 6 g of boric acid the resulting adhesive exhibited a shear strength of 0.82 MPa when bonded samples were treated with water, indicating that boric acid improved the water resistance via the formation of a chelating polymer.

Compared to synthetic resin such as urea formaldehyde, the SF adhesive exhibited lower water resistance. Further modification methods and optimum chemical reagents still need to be investigated.

A new formulation for an environmentally friendly adhesive prepared from SF is identified for the panel industry. The bonding potential of soy protein was developed without any synthetic resin, which will promote industrial utilisation of an agricultural by‐product.

The purpose of this study is to contribute with experimental study of the effects of binary and ternary combinations of river sand (RS), crushed sand (CS) and dune sand (DS) on the physical and mechanical performances of self-compacting concrete (SCC) subjected to acidic curing environments, HCl and H₂SO₄ solutions.

Five SCCs were prepared with the combinations 100% RS, 0.8RS + 0.2CS, 0.6RS + 0.2CS + 0.2DS, 0.6RS + 0.4DS and 0.6CS + 0.4DS. The porosity of sand, fluidity, deformability, stability, compressive strength and sorptivity coefficient were tested. SCCs cubic specimens with a side length of 10 cm were submerged in HCl and H₂SO₄ acids, wherein the concentration was 5%, for periods of 28, 90 and 180 days. The resistance to acid attack was evaluated by visual examination, mass loss and compressive strength loss.

The results showed that it is possible to partially substitute the RS with CS and DS in the SCC, without strongly affecting the fluidity, deformability, stability, compressive strength and durability against HCl and H₂SO₄ attack. The two combinations, 0.8RS + 0.2CS and 0.6RS + 0.2CS + 0.2DS, improved the compactness and the resistance to acid attacks of SCC. Consequently, the improvement in SCC compactness, by the combination of RS, CS and DS, decreased the sorptivity coefficient of SCC and increased its resistance to acid attacks, in comparison with that made only by RS.

The use of RS is experiencing a considerable increase in line with the development of the country. To satisfy this demand, it is necessary to substitute this sand with other materials more abundant. The use of locally available materials is a very effective way to protect the environment, improve the physico-mechanical properties and durability of SCC and it can be a beneficial economical alternative. Few studies have addressed the effect of the binary and ternary combination of RS, CS and DS on the resistance to acid attacks of SCC.

Usual lab coats are designed to protect the wearer from the splats of chemicals, oil, dirt, etc. Simple lab coats are damaged by concentrated acids, thus quickly showing typical small holes along the front when worn in a laboratory where acids are used. For intense handling of acids and other chemicals, special protective lab coats with rubber or vinyl apron or chemical-resistant overalls are used. The purpose of this paper is to investigate the possibility to protect lab coats from acid damages by finishing them with commercially available hydrophobization chemicals.

Two commercial hydrophobic sprays were applied on cotton, polyamide and polyester lab coat materials. Contact and roll-off angles were compared with the untreated textile fabrics before typical laboratory acids were applied on the fabrics. Finally, antibacterial properties of the finished textiles were examined.

Spray 1 resulted in significantly increased hydrophobicity, while spray 2 did not have any influence on the results. With spray 1, the originally hydrophobic fabrics became more hydrophobic, and even the originally strongly hydrophilic fabrics showed large contact angles of 130–140°. Roll-off angles were significantly reduced from 40 to 50° (for the hydrophobic fabrics) or even 90° (in case of hydrophilic fabrics) to approximately 15–25°. Correspondingly, spray 1 showed an increase of the acid resistance of the finished textile fabrics of up to 30 min for the originally hydrophobic fabrics and up to 20 min for the originally hydrophilic ones, with only one polyester fabric showing no acid resistance at all, while spray 2 led to increased antibacterial properties.

While spray 1 can support laboratory safety by increasing the time until acids penetrate through a lab coat, spray 2 can support sterile work in a biological laboratory.

To the best of the authors’ knowledge, increasing the acid resistance as well as the antibacterial properties of lab coats with easily accessible sprays has not been reported before in the scientific literature.

The first major nickel alloy introduced to the industry, about 100 years ago, was a Ni‐Cu alloy 400. This alloy is still widely used in a variety of industries and will continue to be used in this current century. Over the past 100 years, especially in the last 50 years, improvements in alloy metallurgy, melting technology, and thermo‐mechanical processing, along with a better fundamental understanding of the role of various alloying elements has led to new nickel alloys. These have not only extended the range of usefulness of existing alloys by overcoming their limitations, but are reliable and cost‐effective and have opened new areas of applications. This paper briefly describes the various nickel alloy systems developed during the last 100 years and comments on what the future holds for the newer alloys developed in the last 20 years and on the competition faced by these alloys in the new millennium. High‐temperature alloys are not discussed in this paper.

This paper deals with the synthesis of water soluble electrodepositable epoxy resins from maleopimaric acid and epoxy resin. Water soluble methylated urea formaldehyde resin and melamine formaldehyde resin were also synthesised for curing purposes. The coating compositions were prepared from water soluble epoxy resins, water soluble MF resin, water soluble UF resin, red oxide of iron and zinc phosphate. Thereafter the optimum conditions for electrodeposition were determined in terms of voltage, time, solid contents, pH and bath temperature. These anodic electrocoatings had good film properties such as scratch hardness, flexibility, impact resistance and resistance to water, acid, alkali and solvent.

Acryclic copolymers from methacrylic acid‐ethyl acrylate or butylacrylate were prepared and incorporated into the castor oil alkyd structure. The neutralised product was water soluble. Water soluble hexamethoxy methyl melamine resin was prepared and used as curing agent. Several proportions of water soluble acrylic modified alkyds and hexamethoxy methyl melamine resin were examined at various baking schedules. It was established that 30% of the curing agent gave most satisfactory properties after baking at 150°C for 30 minutes. It was found that ethyl acrylate modified compositions had better scratch hardness and acid resistance than those of the butyl acrylate modified composition. However, the latter had better alkali resistance. These surface coating compositions have been recommended as industrial primers.

Selecting the most suitable, cost‐efficient alloy for a given application should not be difficult if the methodology described in this paper is followed. The first step is to identify those alloys with the desired corrosion resistance. Factors other than chemical composition have a bearing on an alloy’s corrosion resistance. Service environment and nature of the product application must also be considered. These conditions are discussed in the text. Consideration should be given to other key issues such as mechanical properties required as well as method of fabrication, design, condition and availability of the candidate alloy. To simplify selection, the author discusses severe corrodents and aggressive environments that are commonly encountered in the process industries, and describes the characteristics of alloys that might be considered for each type of corrosive service. Cross referenced charts position these alloys to show their relative resistance to each type of corrosion attack. While the paper is not designed to replace the technical expertise of a corrosion engineer, the author feels it can serve as a good starting point in the alloy selection process.

Specific chemical environments step out in the industry objects. Portland cement composites (concrete and mortar) were impregnated by using the special polymerized sulfur and technical soot as a filler (polymer sulfur composite). Sulfur and technical soot were applied as the industrial waste. Portland cement composites were made of the same aggregate, cement and water. The durability of prepared cement composite samples was tested in 5 per cent solution of HCl and 5 per cent solution of H₂SO₄ as a function of immersion time. The changes in mechanical strength and mass of the samples were periodically measured. Cement composites impregnated with sulfur composite exhibited limited mechanical strength and mass loss, whereas physico-mechanical properties of Portland cement concrete regressed rapidly. The loss in weight of ordinary concrete impregnated with sulfur composite, kept in aqueous solutions of acids, hydroxides, salts and in water for a year was determined using 100 × 100 × 100 mm samples. The same samples were then used in compressive strength tests.

Specific chemical environments affect industrial objects. Portland cement composites (concrete and mortar) were impregnated with a special polymerized sulfur and technical soot as a filler (polymer sulfur composite). Sulfur and technical soot were applied as industrial waste. Portland cement composites were made of the same aggregate, cement and water. The durability of the prepared cement composite samples was tested in 5 per cent solution of HCl and 5 per cent solution of H₂SO₄ as a function of immersion time. The changes in mechanical strength and mass of the samples were periodically measured. Cement composites impregnated with sulfur composite exhibited limited mechanical strength and mass loss, whereas the physico-mechanical properties of the Portland cement concrete regressed rapidly. The loss in weight of ordinary concrete impregnated with sulfur composite, kept in aqueous solutions of acids, hydroxides, salts and in water for a year was determined using 100 × 100 × 100 mm samples. The same samples were then used in compressive strength tests. The image analysis used for surface destruction monitoring, performed by scanning microscopy for the determination of damaged surface area and the original surface area before acid resistance testing, showed similar results. Based on the image analysis results, a model for predicting the degradation of mechanical strength during durability testing was established. The fact that the calculated and experimental strength values were not vastly different proved the validity of the proposed model. A brief summary of new products related to the special sulfur composite is given as follows: impregnation, repair, overlays and precast polymer concrete will be presented. Sulfur composite as a polymer coating impregnation, which has received little attention in recent years, currently has some very interesting applications.

Author comments: The article is original. The article has been written by the stated authors who are all aware of its content and approve its submission. 3. The article has not been published previously. 4. The article is not under consideration for publication elsewhere. 5. No conflict of interest exists, or if such conflict exists, the exact nature must be declared. 6. If accepted, the article will not be published elsewhere in the same form, in any language, without the written consent of the publisher.

Author comments: 1. The article is original. 2. The article has been written by the stated authors who are all aware of its content and approve its submission. 3. The article has not been published previously. 4. The article is not under consideration for publication elsewhere. 5. No conflict of interest exists, or if such conflict exists, the exact nature must be declared. 6. If accepted, the article will not be published elsewhere in the same form, in any language, without the written consent of the publisher.

In order to obtain desired film properties, alkyd resins are frequently modified by other resins and polymers either by physically blending them or chemically incorporating them. Some of the recent physical modifications of alkyd have already been described in the first part of the article. In this second part, the different types of resins and polymers used for the chemical modifications of alkyd resin are reviewed. A critical discussion on generally recognised advantages and disadvantages of the resultant coating from each modifier is described. Their use in surface coating industry are enumerated. Types of modifier to be used for improving a particular property in the coating are also suggested.