Physical Properties and Chemical Composition of Pistacia atlantica subsp. kurdica (Zohary) Rech. F. gum: Effect of Geographical Region and Tree Gender

Pistacia atlantica subsp. kurdica (PAK) is one of three species in Iran and is indigenous to Kurdistan province. The aim of this reaserch was survey of the chemical composition and physical properties of oleoresin gum extracted from different gender of trees in six regions of Kurdistan province (Armardeh, Kanisoor, Marivan, Dezli, Hawraman and Sarvabad). Principal component analysis (PCA) assisted in analyzing the dependence of geographical regions and tree gender with the variations of chemical components of gum. Significant differences (P < 0.05) were observed in the surface tension, interfacial tension and intrinsic viscosity contents according to gender and geographic region. Spearman rank correlation coefficient results showed significantly positive and negative correlations between gum chemical components and physical characteristics. According to the obtained results and also various medical, cosmetic and food applications of oleoresin, when collecting, the separating extracted oleoresins from trees different regions andgenera is necessary

A novel electrochemical sensor based on Co3O4-CeO2-ZnO multi metal oxide nanocomposite for simultaneous detection of nanomolar Pb2+ and Hg2+ in different kind of spices

Simultaneous and individual determination of Pb2+ and Hg2+ ions were carried out based on the synergistic effect of Co3O4, CeO2 and ZnO nanoparticles into the carbon paste electrode. The morphology of synthesized nanocomposite (Co3O4-CeO2-ZnO) was investigated by Scanning Electron Microscope, Transmission Electron Microscope, X-ray diffraction and Fourier Transform Infrared spectroscopy. The voltammetric current has increased linearly by increasing the concentration of Pb2+ and Hg2+ ions. The linear ranges of the Co3O4-CeO2-ZnO/CPE sensor were obtained 0.27-18.42 (for Pb2+ ions) and 0.42-31.30 nM (for Hg2+ ions), under optimum condition. The detection limits (3Sb/m) were obtained 0.054 nM for Pb2+ and 0.097 nM for Hg2+, respectively. The proposed electrochemical sensor acts as a sensitive and selective method for simultaneous determination of two heavy metal ions and shows excellent repeatability, reproducibility, and stability, with relative standard deviation (RSD) less than 3%. Finally, Co3O4-CeO2-ZnO/CPE was successfully applied for the determination of Pb2+ and Hg2+ in different kind of spices

A comprehensive study on removal of cadmium from aqueous solution by using mesoporous SBA-15 functionalized by 1,5-diphenyl carbazide: experimental design, kinetic, thermodynamic, and isotherm aspects

In this study, a new adsorbent, which was synthesized by using SBA-15Santa Barbara Amorphous. modified with 1,5-diphenyl carbazide, was employed to extract cadmium (Cd) from aquatic systems. First, the sorbent was identified via various characterization techniques, and then the response surface methodology approach was applied for modeling and optimizing the adsorption performance of the sorbent. Under optimum conditions ($\mathrm{pH}=5.75$, an adsorbent dose of 4.55 mg, and a Cd concentration of 25.39 mg/L), an adsorption capacity of 160 mg/g was obtained. In addition, the sorption process was fast; it attained equilibrium in 25.39 min. Furthermore, the sorbent regenerated by nitric acid was reused without any significant loss of adsorption capacity. Finally, the experimental data were studied by different isotherm models and well described by the Langmuir model

A comprehensive study on removal of cadmium from aqueous solution by using mesoporous SBA-15 functionalized by 1,5-diphenyl carbazide: experimental design, kinetic, thermodynamic, and isotherm aspects

In this study, a new adsorbent, which was synthesized by using SBA-15Santa Barbara Amorphous. modified with 1,5-diphenyl carbazide, was employed to extract cadmium (Cd) from aquatic systems. First, the sorbent was identified via various characterization techniques, and then the response surface methodology approach was applied for modeling and optimizing the adsorption performance of the sorbent. Under optimum conditions ($\mathrm{pH}=5.75$, an adsorbent dose of 4.55 mg, and a Cd concentration of 25.39 mg/L), an adsorption capacity of 160 mg/g was obtained. In addition, the sorption process was fast; it attained equilibrium in 25.39 min. Furthermore, the sorbent regenerated by nitric acid was reused without any significant loss of adsorption capacity. Finally, the experimental data were studied by different isotherm models and well described by the Langmuir model

Biosynthesis and characterization of silver nanoparticles by using brown marine seaweed <em>Nizimuddiniazanardinii</em>

2497-2503In this study, the green synthesis of nanoparticles by using both fresh and dry marine macro alga of Nizimuddiniazanardinii was investigated. The Surface Plasmon Resonance bands of silver nanoparticles obtained were characterized by using UV-Vis spectrophotometer with characteristic absorption peaks at 413 and 414 nm. Maximum synthesis of silver nanoparticles was attained within 30 min at pH 8.5, 70&deg;C and 1mM concentration of AgNO3. Also maximum synthesis of silver nanoparticles reveals by characteristic absorption peaks at 432 and 441 nm within 2h at pH 7.5, 70&deg;C and 1mM Ag2SO4. The SEM images demonstrated these nanoparticles as spherical structures with average size of 60 nm. EDX study showed the major signal of silver metal with concentration of 50.06% in the fresh seaweed. The structure of Ag-NPs was determined by X-ray diffraction (XRD). FTIR showed that the function groups of hydroxyl, carbonyl and amine compounds in Nizimuddiniazanardinii extracts were involved in the reduction of aqueous AgNO3. This method of Ag-NPs synthesis is environmentally safe with potential utilization in biomedical and agriculture applications

Spectrophotometric determination of selenium in Spirulina algae using Diaminotoluene reagent

Due to the progress of science and technology in health and medicine, selenium is mentioned as an excellent antioxidant in preventing the growth of cancers cell and even helping the process of cell growth. In most countries, plant foods are the main source of selenium. Among these plant sources, a kind of green-blue algae from the species of cyanobacteria should be mentioned, which is introduced as Spirulina algae. In addition to providing the body with the selenium it needs, spirulina is an excellent source of essential proteins, minerals, vitamins and amino acids. However, the amount of selenium required by the body and the fact that its excessive increase causes toxicity doubles the need to pay attention to its accurate quantitative measurement. These measurements are usually performed with costly and long-term methods such as ICP-AES. Therefore, in this study, the suitable specific ligand (Diaminotoluene) for selenium was used with low cost and high availability, using simple, low cost and fast technique as UV-spectrophotometric method.The results of the analytical method validation indicated that this ligand has high productivity and also this method should be quite suitable for replacement with high cost methods such as ICP-AES. In addition, this method used can provide all the parameters required to analytical method validation

Genetic algorithm-based wavelength selection in multicomponent spectrophotometric determination by PLS: Application on sulfamethoxazole and trimethoprim mixture in bovine milk

The simultaneous determination of sulfamethoxazole (SMX) and trimethoprim (TMP) mixtures in bovine milk by spectrophotometric method is a difficult problem in analytical chemistry, due to spectral interferences. By means of multivariate calibration methods, such as partial least square (PLS) regression, it is possible to obtain a model adjusted to the concentration values of the mixtures used in the calibration range. Genetic algorithm (GA) is a suitable method for selecting wavelengths for PLS calibration of mixtures with almost identical spectra without loss of prediction capacity using the spectrophotometric method. In this study, the calibration model based on absorption spectra in the 200-400 nm range for 25 different mixtures of SMX and TMP Calibration matrices were formed form samples containing 0.25-20 and 0.3-21 μg mL-1 for SMX and TMP, at pH=10, respectively. The root mean squared error of deviation (RMSED) for SMX and TMP with PLS and genetic algorithm partial least square (GAPLS) were 0.242, 0.066 μgmL-1 and 0.074, 0.027 μg mL-1, respectively. This procedure was allowed the simultaneous determination of SMX and TMP in synthetic and real samples and good reliability of the determination was proved

Simultaneous reduction of Cr (VI) and degradation of azo dyes by F-Fe-codoped TiO2/SiO2 photocatalysts under visible and solar irradiation

A new TiO2/SiO2 photocatalyst codoped with fluorine and iron was synthesized using sol-gel process and immobilized onto glass beads using coupling two methods of dip-coating and heat attachment. The prepared samples were characterized by XRD, FT-IR, DRS-UV/Vis, FESEM, EDX, TEM and N2 Adsorption/Desorption analysis. The effective parameters of pH, flow rate and photoreactor vesselsâ angle against solar irradiation on degradation performance were optimized. Subsequently, the photocatalytic activity of the prepared nanocomposites was investigated in an innovative fabricated photoreactor using a four-component pollutant mixture of Cr (VI), basic red 29, basic blue 41 and basic yellow 51, under visible and solar irradiation. Furthermore, the effectiveness of photoreactor performance was assessed under various outdoor climate conditions as natural irradiation source. Consequently, UV/Vis spectrophotometry results showed significant efficiency of photocatalytic removal of the pollutants mixture. TOC results of 74.39% and 78.04% for removal of organic content of the sample under visible and solar light, respectively, were also confirmed the great capability of the designed system for the simultaneous removal of some hazardous inorganic and organic contaminants under natural light sources.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author

<span style="font-size:12.0pt;font-family:"Times New Roman";mso-bidi-font-weight: bold" lang="EN-US">Assessment of heavy metals by ligand-less cloud point extraction in sediment and <i>Holothuria parva </i>(Echinodermata, Holothuroidea) </span>

825-830The concentrations of heavy metals were determined in organs of Holothuria parva and sediment from three stations in the Qeshm, Iran. A ligand-less Cloud Point Extraction (CPE) procedure was used for preconcentration of trace metals as pretreatment step to determination of lead and cadmium by Graphite Furnace Atomic absorption Spectrometry (GFAAS). Concentration of heavy metals in body wall, gut and sediment were obtained 14.05, 5.72 and 41.66 µg/g for lead and 0.722, 0.493 and 3.27 µg/g for cadmium, respectively. Limit of detection (LOD) values of lead and cadmium were 0.037 and 0.028 µg/g, respectively. Relative standard deviation (RSD) for six replicate determinations of lead and cadmium were 2.68% and 1.20%, respectively. Concentrations of lead and cadmium in sediments and organs of sea cucumbers differed significantly, suggesting that this sea cucumber should not be considered as an ideal bioindicator of lead and cadmium pollutants in the sediment