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Historically, paints designed to protect steel and other metals have been formulated using anticorrosive chromate pigments, which are currently under environmental restrictions. During the investigation reported here, various phosphate compounds. The pigments prepared were characterised using a variety of chemical and spectrophotometric methods of analysis including emission atomic absorption, transmission electron microscope, X‐ray diffraction, in addition to thermal gravimetric analysis. The pigments were also evaluated according to relevant international standard testing methods. The phosphates prepared were incorporated into anticorrosive paint formulations, to replace the imported zinc phosphate pigment, containing medium oil alkyd resin, and melamine formaldehyde resin. Paint films obtained were tested in artificial seawater for 28 days for anticorrosion properties. The results indicated that the paint films had good anticorrosive protection properties that could be attributed to the pigments prepared and the resins used.

Substitution of zinc chromate or zinc yellow, traditionally used as anticorrosive pigment, for other phosphate‐based pigments that are not hazardous to health and have the same anticorrosive behaviour or even better, is studied in this paper. Four alkyd paints were specially prepared; two of them contained calcium acid phosphate or micronised zinc phosphate as anticorrosive pigments respectively. A paint containing zinc chromate was used as reference and a paint without anticorrosive pigments was used as a blank, in which the other ingredients were increased proportionally to attain the desired PVC relationship. The corrosion behaviour of low carbon steel panels coated with these paints in a 3 per cent NaCl solution was assessed by electrochemical impedance spectroscopy (EIS). In addition, other painted panels were evaluated by salt spray and humidity chamber tests. Results of all tests showed that the paint with calcium acid phosphate and especially that with micronised zinc phosphate exhibited better behaviour than paint with zinc chromate. Analysis of impedance parameters (ionic resistance and capacitance of the paint film) against immersion time allowed the paints to be ranked in the same order as that obtained with salt spray and humidity chamber tests.

The purpose of this paper is to study the influence of changing printing parameters (powder layer thickness and binder saturation) in a three dimensional printing machine (3DP) on the transformation of 3DP printed plaster of paris to hydroxyapatite by low temperature phosphorization.

Plaster of paris‐based powder mixture was used to print specimens using different powder layer thickness (0.080, 0.10 and 0.20 mm) and saturation ratio (1 and 2). Subsequently, density, microstructure, mechanical properties, transformation rate and phase composition were analyzed to compare the influence of such printing parameters on properties.

It was found that printing parameters strongly affect the transformation efficiency and properties of the samples. The sample printed at layer thickness of 0.10 mm and saturation ratio of 1 yielded the highest transformation rate, density and greatest flexural modulus and strength after conversion. This was related to the sufficiently low density structure with good mechanical properties of the as‐fabricated 3DP sample which was suitable for the low temperature phosphorization process. Hydroxyapatite and monetite were found to be the main phases after conversion and the content of each phase depended on the conversion time and on also the printing parameters.

The optimal printing parameters were true for the materials used in this study. In the case of using other materials formulation, the optimal printing parameters might be different from these values.

The results presented here can be used as a guideline for selecting printing parameters in 3DP machine for achieving properties as desired for specific applications or post‐processing techniques.

The paper demonstrates the printing parameters that were needed to be considered for efficient phase transformation and high mechanical properties.

The paper studies the effect of modification of zinc orthophosphate on the anticorrosion efficiency thereof in organic coating. The zinc orthophosphate dihydrate and tetrahydrate and the reaction of phosphate anion with hydroxyl binder groups are compared. The highest anticorrosion efficiency is reached with pigments which are modified by organic corrosion inhibitors. The highly water soluble phosphate pigments reduce the anticorrosion coating properties. The effect of cation in phosphate pigments on the corrosion inhibition was confirmed.

In one process used for the manufacture of phosphoric aicd, ground phosphate rock containing calcium phosphate is reacted with dilute sulphuric acid. A chemical reaction takes place and phosphoric acid and gypsum (calcium sulphate) are formed. This process is carried out by ICI Fertilizers in their phosphoric acid plant at Billingham in Cleveland. The phosphoric acid is made in a large reactor which has seven large agitators to move the solids from stage to stage and prevent them settling. Traditional materials of construction for use in this process have included alloy 20 type stainless steels. When this material was used for the manufacture of agitators it was found that failure was occurring too frequently, often as a result of weld failure at the top flange and where the blades join the shaft.

The aim of this work was to propose a method to prepare composite phosphate conversion coating (CPCC), including ternary phosphate conversion coating (TPCC) and binary phosphate conversion coatings (BPCC), with one-step chemical conversion and to reveal and compare the corrosion resistance between TPCC and BPCC.

In this work, a calcium–manganese–zinc (Ca–Mn–Zn) TPCC was prepared on the surface of magnesium alloy (MA) AZ91D with one-step chemical conversion method; for Ca-Mn-Zn@TPCC, its microstructure was characterized with scanning electron microscope observation and scanning tunneling microscope detection, and its composition was characterized with energy dispersion spectroscopy and X-ray photoelectron spectroscopy analyses. Particularly, the corrosion resistance of Ca-Mn-Zn@TPCC and its comparison with Ca–Mn, Ca–Zn and Mn–Zn BPCCs were clarified with electrochemical and immersion measurements.

Ca-Mn-Zn@TPCC, which was composed of Ca, Mn, Zn, P and O, exhibited a mud-shaped with cracks microstructure, and the average crack width, terrain fluctuation and coating thickness were 0.61 µm, 23.78 nm and 2.47 µm, respectively. Ca-Mn-Zn@TPCC provided good corrosion resistance to MA AZ91D; in NaCl solution, the total degradation of Ca-Mn-Zn@TPCC consumed eight days; corrosion products with poor adhesion peeled out from Ca-Mn-Zn@TPCC-coated MA AZ91D spontaneously. Besides, the corrosion resistance of Ca-Mn-Zn@TPCC was better than that of Ca-Mn@BPCC, Ca-Zn@BPCC or Mn-Zn@BPCC.

The successful preparation of Ca-Mn-Zn@TPCC on MA AZ91D surface confirmed the proposed method to prepare CPCC with one-step chemical conversion was feasible; at the same time, it was further confirmed that for phosphate conversion coating, ternary coating had better corrosion resistance than binary coating did.

The purpose of this study is to develop a chicken product that could supply calcium, vitamin E and vitamin C together with high sensory acceptability. The present study was envisaged to develop low-fat chicken patties fortified with calcium, vitamin E and vitamin C without any adverse effects on sensory attributes.

Three different levels of calcium lactate as a source of calcium viz. 1.5, 1.75 and 2.0 per cent, α-tocopherol acetate for vitamin E at 0.019, 0.023 and 0.029 per cent and ascorbic acid for vitamin C at 0.09, 0.12 and 0.15 per cent in low-fat chicken meat patties were tried and the optimum level was standardized based on physico-chemical, proximate and sensory parameters.

The calcium lactate at 1.75 per cent, α-tocopherol acetate at 0.029 per cent and ascorbic acid at 0.15 per cent were found to be optimum on the basis of proximate, physico-chemical and sensory parameters. The textural attributes of the standardized product was comparable to that of the control. The a*, b* and Chroma values for the low-fat chicken patties fortified with calcium, α-tocopherol and ascorbic acid were significantly higher (p < 0.01) than that of the control. The calcium and ascorbic acid concentration of the standardized product was significantly higher (p < 0.01) than that of the control.

The levels in the fortified product were found to be suitable to achieve a 20 per cent RDA of calcium and almost a complete RDA for vitamin C. The research findings demonstrated the development of a single-designer chicken product rich in calcium, vitamin C and vitamin E.

This work concerns the electrodeposition of highly pure brushite (CaHPO₄·2H₂O) on titanium alloy substrates and the transformation of the brushite to hydroxyapatite (HAp) Ca₁₀(PO₄)₆(OH)₂ as a coating for orthopaedic implants. Thus, the electrodeposition of electrolyte containing calcium nitrate and ammonium hydrogen phosphate was carried out. The influences of the substrate surface treatment, the electroplating conditions (bath composition, current density, pH value and temperature) and the hydrothermal post treatment conditions on the deposition rate, the throwing power, the adhesion, the morphology and the structure of the coating were evaluated. High adhesion bond strength (around 23 mPa) was achieved on a rough clean substrate, which is slightly higher than plasma sprayed HAp coating on titanium alloy.

The statement of the Minister of Agriculture, Fisheries and Food, coming so quickly after the ban on the use of cyclamates in food and drink in the United States, indicates that the new evidence of carcinogenesis in animals, placed at the disposal of the authorities by the U.S. F.D.A., has been accepted; at least, until the results of investigations being carried out in this country are available. The evidence was as new to the U.S. authorities as to our own and in the light of it, they could no longer regard the substances as in the GRAS class of food additives. It is, of course, right that any substance of which there is the slightest doubt should be removed from use; not as the result of food neuroses and health scares, but only on the basis of scientific evidence, however remote the connection. It is also right that there should always be power of selection by consumers avoidance is usually possible with other things known to be harmful, such as smoking and alcohol; in other cases, especially with chemical additives to food and drink, there must be pre‐knowledge, so that those who do not wish to consume food or drink containing such additives can ascertain from labelling those commodities which contain them.