Iranian Journal of science and Technology (A: Siences)
Volume:37 Issue: 1, Winter 2013

The methanolic extracts, infusions, decoctions and hydrosols of six plants were investigated for their total phenolic contents, antioxidant and antimicrobial activities: Mentha piperita (Peppermint), Thymus vulgaris (thyme), Melissa officinalis (lemon balm), Ocimum basilicum (basil), Rosmarinus officinalis (rosemary) and Salvia officinalis (sage) (Lamiaceae). Total phenolic contents were determined by Folin Ciocalteu procedure and ranged from 111.03 ± 0.6 (sage methanolic extract) to 19.07 ± 0.0 mg (basil methanolic extract) gallic acid equivalent /g extract. The antioxidant activity was evaluated by two methods, DPPH and phosphomolybdenum assays. The decoction of rosemary showed the highest DPPH radical scavenging activity (IC50 = 8.36 μg/mL). The methanolic extract of Peppermint showed the highest total antioxidant activity (241.85 ± 1.9 mg ascorbic acid equivalent /g extract) measured by phosphomolybdenum assay. The antimicrobial activities of herbs were tested against eight bacteria and two yeasts.

The Ali-Abad porphyry copper deposit is located in the Central Iranian magmatic belt. As a result of subduction magmatism, Oligo-Miocene leucogranitoid rocks have intruded into conglomerates of lower Cretaceous age. Due to contact metamorphism the following mineral assemblage has occurred in the altered conglomerate: Garnet (andradite-grossular) + epidote+ quartz + calcite + pyrite Skarnification have only occurred in reactive carbonate clasts of the conglomerates. Chemical composition of garnets and classic discrimination scheme imply the porphyry copper related skarn-type mineralization. Garnets are characterized by abrupt chemical zoning area and thin bands. REE pattern of skarn garnet and host granite have similar trends, so it is concluded that garnets are hydrothermal in origin. The garnet mineralization episode occurred during skarnification, giving hydrothermal fluid temperatures of 422-472 ºC, likely this episode corresponds to the fluid boiling and high fO2 of garnet forming processes in the skarn system. Probably, the temporal decrease of hydrothermal fluid pressure led to rapid growths of andradite zones i.e., extensive hydrofracturing, porosity of conglomerate could be the dominant conditions which led to boiling of hydrothermal fluids and precipitation of andradite garnet.

In this paper, a new numerical method for solving time-fractional diffusion equations is introduced. For this purpose, finite difference scheme for discretization in time and Chebyshev collocation method is applied. Also, to simplify application of the method, the matrix form of the suggested method is obtained. Illustrative examples show that the proposed method is very efficient and accurate.

Exposure buildup factors have been calculated by Monte Carlo method for point isotropic gamma ray sources, penetrating a two-layer spherical shield of water surrounded by lead, and the effect of bremsstrahlung radiation on buildup factors has, in particular, been investigated, the results of which are in good agreement with previous works. The buildup factors were then calculated for various combinations of water and lead layers at some gamma ray energy points in the range from 0.04 MeV to 10 MeV and for shield thicknesses from to 10 mean free paths (mfp). From the results obtained, one can select the proper (or optimum) water and lead combination which results in minimum value of buildup factor for a two-layer water-lead shield of a given thickness (in mfp) at each energy point. Here the optimization analysis has been performed for a shield of 10 mfp thick at gamma ray energies from 0.04 MeV to 10 MeV.

In this paper, Genetic Algorithms (GAs) are employed to control simultaneous linear systems in both state and output feedback. First, the similarity transformation is applied to obtain parameterized controllers. This requires solution of a system of equations and also some non-linear inequalities. GAs are used to solve these equations and inequalities. Therefore, the paper presents an analytical method for finding parameterized controllers and employs a numerical method to enhance the solution. Three numerical examples are presented to illustrate the effectiveness of the method and to compare the results with previous results.

Little is known about Chironomidae in Iran. This article is the second one on chironomid larval identification in running waters of Iran. Samples were collected from five sites in the Golpayegan River, (Isfahan-Iran), about 55 km along the river course. The sampling was done four times: February and November 2003, May and July 2004. Samples were hand sorted in the laboratory and the larvae identified at generic level, using available identification keys. Thirty five genera were identified in four subfamilies, including Chironominae (15 genera), Orthocladinae (13 genera), Tanypodinae (5 genera) and Diamesinae (2 genera). 17 genera of these are reported from the Golpayegan River for the first time.

A computational method for numerical solution of a nonlinear Volterra and Fredholm integro-differential equations of fractional order based on Chebyshev cardinal functions is introduced. The Chebyshev cardinal operational matrix of fractional derivative is derived and used to transform the main equation to a system of algebraic equations. Some examples are included to demonstrate the validity and applicability of the technique.

The study aimed to investigate the microsporogenesis, tapetum and pollen development in Petunia hybrida Juss. under control and air pollution condition. The connective shows a well-developed placentoid, giving the sporogenous tissue a crescent-shape. The sporogenous tissue of each of the four anther locules is surrounded by dimorphic tapetum. The outer (towards the epidermis) and inner (towards the connective) tapetal layers differ in shape, staining intensity and degree of vacuolization. During microsporogenesis and pollen maturation, the tapetum undergoes several changes and ultimately degenerates after pollen mitosis. The tapetum is the secretory type. Microsporogenesis with simultaneous cytokinesis forms tetrahedral tetrads of microspores. Mature pollen grains are prolate, tricolporate/tricolporoidate with furrows disposed along the polar axis and three lowly developed pores with striate-reticulate sculpture. Under air pollution, microsporogenesis was normal till tetrad stage. After this stage, some tetrahedral tetrads were still present and some pollen grains were irregular shaped, shrunk and fragile. Some tapetal cells were smaller and the number of their nuclei was less compared to those of the control. Cellular material release was higher in polluted pollen. SDS-PAGE pattern in polluted pollen did not show significant difference compared to the control.

In this paper we construct the category of coverings of fundamental generalized Lie group-groupoid associated with a connected generalized Lie group. We show that this category is equivalent to the category of coverings of a connected generalized Lie group. In addition, we prove the category of coverings of generalized Lie groupgroupoid and the category of actions of this generalized Lie group-groupoid on a connected generalized Lie group are equivalent.

14-Aryl- and 14-alkyl-14-H-dibenzo [a,j]xanthenes are prepared from the reaction of aromatic- and aliphatic aldehydes with β-naphthol in the presence of catalytic amounts of 4-dodecylbenzenesulfonic acid(DBSA) as a surfactant-type Brønsted acid catalyst in toluene and under solvent-free conditions in excellent yields and short reaction times. The catalyst was recovered and reused for five successive times without considerable loss in its activity.

In this article, an analytical approximate solution of nonlinear fractional convection-diffusion with modified Riemann-Liouville derivative was obtained with the help of fractional variational iteration method (FVIM). A new application of fractional variational iteration method (FVIM) was extended to derive analytical solutions in the form of a series for this equation. It is indicated that the solutions obtained by the FVIM are reliable and an effective method for strongly nonlinear partial equations with modified Riemann-Liouville derivative.

The present study aimed to evaluate the antimicrobial activity of a hetroalkyl oximec synthetic compound derivative (Benzophenone O-4-bromoethyl oxime) against two gram positive and three gram negative bacteria. The antibacterial characteristic of this compound was shown using the circular zone diameter of bacterial growth inhibition by disk-diffusion method. In addition, the random amplified polymorphic DNA (RAPD) technique using twenty-three primers was performed to investigate the DNA polymorphism of bacteria that were affected by the synthetic chemical drug. Among these, only 18 primers were found efficient for reproducible banding pattern. Disappearance or appearance of bands between controls and treatments confirm rearrangements and DNA damages in the priming binding sites of bacterial genome. The results show that the RAPD method can be a useful identification tool for studying the DNA polymorphism created by synthetic chemical drugs. The results obtained with this technique showed significant differences between the RAPD profiles.