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In this paper, the synthesis and the application of chromic oxide as a high temperature pigment have been reported. To synthesise chromic oxide, solid‐state reaction using sulphur and sodium chromate tetrahydrate was undertaken. Morphology of the pigment synthesised was investigated by scanning electron microscopy. Formation of the chromic oxide was observed at 888°C in an oxidising atmosphere. Thorough washing of the resultant pigment played a vital role in the aggregation of the pigment particles, as demonstrated by a particle size characteristics.

To investigate the effects of the temperature of synthesis and of the thermal treatment of zinc chromate on the properties of the zinc chromate pigments.

Zinc chromate pigments was prepared using zinc salt solution, sodium hydroxide and potassium dichromate solutions. The reaction temperature was varied in order to evaluate the effect of the reaction temperature on the properties of the pigment synthesised. The pigment obtained was heated to 10°C above the critical temperature in order to investigate the effect of thermal treatment on the pigment properties. SEM, XRD, XFR and STA were employed for the characterisation of the pigments synthesised.

Reaction temperature had a significant effect on the properties of the resulting pigment. Thermal treatment of the pigment caused the decomposition of the zinc chromate phase to ZnO, ZnCr₂O₄ and K₂CrO₄ phases. The glaze containing zinc chromate had satisfactory colour characteristics.

The study focused on the preparation and evaluation of zinc chromate as a substitute for praseodymium zircon in glaze. The study could be extended to investigation of similar inorganic pigment for similar purposes.

The information on the effects of the reaction temperature of pigment synthesis and of thermal treatment of the pigment is useful for industrial production of the pigment of satisfactory properties.

Novel use of zinc chromate as a lower‐cost substitute for praseodymium zircon in glaze and understanding of the effects of the production conditions on the properties of the resulting pigment and the glaze.

Long afterglow Sr₂MgSi₂O₇ (SMS) phosphor was prepared by Douby's methods at high temperature and reductive atmosphere. The excitation and emission spectra of this phosphor showed that both had broad bands and that the main emission peak at 469 nm was due to 4f‐5d transitions of Eu⁺² and implied that the luminescence centres Eu⁺² occupied the Sr⁺² sites in the Sr₂MgSi₂O₇ host. The phosphor doped only with Eu ions did not demonstrate the long afterglow phenomenon, but when co‐doped with Dy⁺³ ions in the SMS matrix, significant long afterglow was observed.

Zinc potassium chromate (4Zn·O₄CrO₃·K₂O·3H₂O) was prepared using zinc salt solution, sodium hydroxide and potassium dichromate solutions. The pigment synthesised was investigated by various methods. Upon heating, this pigment underwent decomposition to form ZnCr₂O₄, K₂CrO₄ and ZnO. The pigment obtained was successfully used in the preparation of glaze and then on a tile. The L*, a* and b* values of the fired glaze were 71.607, 2.695 and 67.327, respectively.

The purpose of this paper is to develop a new method for biomolecular recognition based on light scattering of ZnS:Mn nano‐particle functionalised with biotin.

ZnS:Mn nano‐particles was successfully synthesised from quaternary water‐in‐oil micro‐emulsion system. The addition of biotin and the subsequent specific binding events alter the dielectric environment of the nano‐particle, resulting in a spectral shift of the particle plasmon resonance. Cyclohexane was used as oil, Triten X‐100 as surfactant, n‐hexanol as a co‐surfactant and mercaptoethanol for the best linking of biological part to nano‐particle. Measurement of the content of avidin was achieved by detecting the Department of Biomedical Engineering change in the excited emission. For qualitative and quantitative analyses of this product, scanning electron microscopy, transmission electron microscopy, energy dispersive X‐ray spectroscopy and spectrograph techniques were used.

It was observed that with reducing particle size, emission shifted to the lower wave lengths. In addition, with conjugation between avidin and biotin by mercaptoethanol in biologic media, spectral emission decreased.

The method developed could be utilised for synthesis of a variety of ZnS:Mn nano‐particles for a wide range of diagnostic applications.

The method for biomolecular recognition based on light scattering of ZnS:Mn nano‐particle functionalised with biotin developed was novel.

ZnS:Cu phosphors were prepared by co‐precipitating Cu along with ZnS using H₂S and thiourea. Phosphors giving luminescence at around 530 nm were prepared. The difference in the characteristic properties among the samples prepared appeared to be due to the formation of nanoparticles during the preparation of the samples by different methods.

The aim of this paper is to apply a watery infrared filter for silicon solar cell efficiency enhancement in Kerman province of Iran as a talent region for solar energy production.

With this research, the water is applied as a filter for silicon solar cells in different volumes and thicknesses.

The obtained results showed that using various amounts of water could be a suitable choice for increasing the efficiency of silicon solar cells.

Other wavelength regions just cause the increase in the entropy and decrease in the efficiency. With this research, the water is applied as a filter for silicon solar cell in different volumes and thickness. The obtained results showed that using different thicknesses of water could be suitable choice for increasing the efficiency of silicon solar cell.

This paper aims to study the Lut desert, also known as the Dasht–e–Lut, starting with a summary of its location as a large salt desert in southeastern Kerman, Iran, as well as its climate, being one of the world’s driest places. Next, a statistical analysis is performed based on a reasonable minimum level of 10 per cent. The computation of electric energy produced by sunlight in the studied region is, then, provided using a number of high-efficiency and suitable solar cells. Finally, the authors will compare the production of electrical energy to the consumption energy in Iran and Kerman province.

According to calculations of the present study and the analyses of the tables and charts provided, the use of solar energy and the amount of energy used in different areas was discussed. Lut desert in Iran is one of the touristic attractions of Kerman province: while only a very small area of this desert known as the Kalut is of interest to tourists, the vast remaining area of this desert is currently left without use. Lut and its surrounding towns and villages are not suitable for agricultural due to the lack of water in the region, and relatively poor people live within the area. The findings of this study showed that throughout the region, there is a very high potential for energy supply of Kerman and Iran.

The practical use of Lut desert potential in the production of electric energy from solar energy, besides its significant role in cost reductions, can also positively affect the living standards of local residents as well as job and income creation for the country. Efficient use of only 10 per cent of the area of Lut desert, via using its solar energy, can produce a considerable amount of energy for the region and for the country in large. Although the present study only investigated the solar energy of the region, it also has a high potential in wind energy and geothermal optimum use. The research team will, hence, continue its work on calculating the amount of energy generated from all types of renewable energy in this area. This paper showed that application of solar cells in this region is appropriate for providing a magnificent amount of electric-energy requirements of Kerman province and of Iran.

In recent years, Iran’s nuclear, oil and natural-gas industries have been the subject of intensifying sanctions from certain international communities. Now, the country wants to develop a sector in which it has more leeway, i.e. the renewable energy; wind and solar energies are always available, and no one can put sanctions on them. Also, to provide household electricity in remote areas (which are not connected to the mains electricity grid), energy storage is required for use of renewable energy. Usually, however, renewable energy is derived from the main electricity grid, and this means that as the mains electricity grid is organized so as to produce the exact amount of energy being consumed at that particular moment, the energy storage is mostly not applied. Energy production on the mains electricity grid is always set up as a combination of renewable-energy plants, as well as other power plants (e.g. the fossil-fuel power plants and nuclear power). This combination, nevertheless, is essential for this type of energy supply (i.e. the wind turbines, solar power plants, etc).

Regarding the renewable energies, the cost of producing electricity and the remaining reserves from fossil fuels in Iran is compared with the same in other countries. Several advantages of renewable energies are studied in the present research with emphasis on solar energy; the Lut desert in Iran is introduced as a high potential for supplying the country’s energy. Various effects of such generation of energy on economy, environment, and public health are also studied.

The purpose of this study is to investigate the effect of presence of buried flexible pipe on the bearing capacity of shallow footing. First, a model study is performed where shallow footing model is tested for its load settlement behavior, with and without the existence of buried PVC pipe lying vertically below the base of the footing.

The experimental set-up consisted of a steel box filled with sand at two different relative density values [RD = 50 per cent (medium dense) and RD = 80 per cent (dense sand)] and vertical load was applied on the model footing through hydraulic jack and reaction frame arrangement connected with a proving ring. Test results are verified numerically using commercially available finite element code PLAXIS 2D. With due verification, a parametric study has been conducted, numerically, by varying the range of input parameters, such as unit weight, angle of internal friction, diameter of buried conduit and the Elastic modulus of the soil to assess the pre cent reduction in the capacity of the foundation soil because of the presence of underlying buried flexible pipe.

Results show that for each footing, there exists a critical depth below which the presence of the buried conduit has negligible influence on the footing performance. When the conduit is located above the critical depth, the bearing capacity of the footing varies with various factors, such as geotechnical parameters of soil and location and diameter of the buried conduit.

It is an original paper performed to assess the presence of buried flexible pipe on the bearing capacity of the shallow footing.