In this research, three natural extracts of pomegranate, red tea, and green tea were used in dye- sensitized solar cell (DSSC). The characteristics of DSSCs made of three natural dyes were investigated by photovoltaic measurements and electrochemical impedance spectroscopy technique. A solar cell fabricated of the ruthenium dye (N719), as a standard dye, was used for comparison. The DSSCs were assembled using two glass plates (anode and cathode) coated with transparent conducting oxide. The anode thin film was prepared on the conductive glass plate using titanium dioxide (TiO2) nanoparticles by doctor blade method. The cathode electrode was coated by a catalyst Pt. Comparing these dyes with 29 natural dyes investigated by other researchers revealed that the red tea extract can be used as a reasonable dye in solar cells. The red tea cell showed a fill factor of 0.42 and an efficiency of 1.02%.

Background and Objective: Production of pigments by microorganisms has significant importance than other sources; because microorganisms are grow quickly, easier extraction and higher yields. The purpose of this study was isolation and identification of pigment-producing microorganisms from soils in regions of West Mazandaran province in the second half of 1389 and toxicity effect pigments.Materials & Methods: 70 soil samples from the Mountain West Mazandaran province (Chalus, Tonekabon and Ramsar) were collected and after of prepared serial dilution, each of samples was cultured on Nutrient agar and Sabouraud Dextrose Agar. After, colonies were selected with the ability to produce pigment. Pigment extraction was done by Methanol extraction on Sediment microorganisms. Different color compounds were identified by TLC. Molecular identification of microorganisms was performed by rDNA PCR Sequencing. Also, oral acute toxicity of pigments were evaluated on the albino mice.Results: Seven microorganisms were identified include Aspergillus sp, viridians Aerococcus, Methyl bacterium sp, Bacillus sp, Eurotium rubrum, Micro bacterium testacies and Acinetobacter johnsonii. Oral acute toxicity study of the Pigments on rats was no mortality in the maximum dose. However, studies of liver enzymes and liver histopathology were showed the pigments reversible toxic effect on the liver tissue in maximum dose.Conclusion: As regards the natural pigments in the proper doses are healthier than their chemical, their application is useful in different industries. Also to determine the structure of this pigment and to removal of toxic groups of pigments can be used in various industries.

The aim of this research was to study the effect of astaxanthin pigment on growth performance (weight again, specific growth rate and final body weight), survival and pigment accumulation in postlarvae of white leg shrimp. This study was carried out in spring 2011 at Kolahi Aquatic Development Center. Some 8-day postlarvae with mean (±SD) initial weight 5.3±1.6mg were fed diets with containing various levels (0, 50, 100 and 200mg/kg diet) of astaxanthin pigment for 30 days. Shrimp fed with diet without astaxanthin pigment served as control. Shrimp fed diets containing 50, 100 and 200 mg/kg astaxanthin, growth performance and survival was significantly higher than control group. The pigment accumulation rate was determined by high performance liquid chromatography (HPLC). The analysis of pigment accumulation showed that the higher increasing astaxanthin pigment amount in the diets, the higher growth performance and survival rate in postlarvae; as in postlarvae fed with 200 mg astaxanthin/kg, final weight (700.6±12.7mg) and survival rate (82±1.5%) was significantly higher than control group (484.2±28.9, 54.7±4.5% final weight and survival rate, respectively). Due to nutritional properties of astaxanthin pigment and the positive effect on growth and survival, the feeding of postlarval white leg shrimp with the diet containing at least 100 mg astaxanthin/kg is recommended.

In this research an organic dye called Porphyrin, which showed TCPP in abbreviation form, synthesis.In order to characterized this dye UV-Vis absorptive spectrum was derived and compared with other articles samples. This dye was used to build a dye sensitized solar cell (DSSC), and after characterization of this cell the function of it was measured. Porphyrin absorption spectra obtained in this study is consistent with similar in iranian and international samples that Confirm the accuracy of the porphyrin and a high absorbtion intensity is achieved. A DSSC based TCPP have a good performance that open circuit voltage 0.49 v and short circiut current density 3.6 mA/cm2 and efficiency 0.7% has achieved.

In this study, a new red pigment with good thermal and chemical resistance has been synthesized by solution combustion method. By substituting choromium ions in aluminium ion sites in YAlO3 perovskite structure and synthesis the YAl1-yCryO3 (y=0.01-0.1) solid solution, can provide red color. In the first step, effect of various mineralizers on YAlO3 formation has been investigated. Then effect of the doped choromium amount on the pigment color was studied. Latter, thermal stability and chemical resistance of synthesized pigment were investigated. Results showed that the most appropriate mineralizer system for the formation of YAlO3 perovskite was NaF:MgF2:Li2CO3 (3:2:1 by weight). Calcination at 1400oC for 4 hr is the best condition for preparation of pigments with suitable color. The highest redness (a*) has been obtained when y was 0.03 (YAl0.97Cr0.03O3). Application of the prepared red pigment in low and high temperature glazes, demonstrated high chemical and thermal stability.

In this study, production of black pigments for glass glazing was undertaken by using Cr, Mn, Fe, Ni, Cu and Co elements. After calcination at different temperatures (1200-1350 °C), the synthesized pigment was milled and sieved. The resulting pigment were characterized by using XRD, PSA, and STA. Different amounts of pigment (5-10 wt.%) was added to a transparent glaze and applied on a cleaned glass and then fired at 650 °C. The glazed samples were analyzed by UV-vis. spectrophotometer. The results showed that black pigment particles containing Cr, Fe, Co, Cu and Ni synthesized at 1350 °C give an appropriate black color to the final glaze.

In recent years hybrid pigments based on mica and an organic pigment have been prepared and used in different applications. In this paper, preparation of a colored mica was investigated and the samples were characterized by ultraviolet visible spectroscopy, optical and electronic microscopes. Results showed that the dye-uptake (%) on the mica surface varied from 10 to 80 percent depending on pH. Maximum dye-uptake was observed for pH 5-6. L*, a*, b*, h and C* values from colorimetric investigation demonstrated that colored mica samples of yellow, blue, gray and purple were prepared. It was shown that by this method not only the primary colors but also the secondary colors can be prepared.