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Showing 81 results for Ca


Volume 8, Issue 2 (10-2009)
Abstract

The Caspian sea as a unique habitat has accommodated Rutilus frisii kutum for as long as the course of history but has undergone extreme ecological & managerial disturbances over the recent centuries which has in turn, borought about dire consequences including the formation of a potentially fragile ecosystem. In fact, various researches undertaken on this issue has shown that the specter of such ominous changes in ecosystem and the living resources of the Caspian Sea loom near. The present study aims at investigating the sexual and biological aspects of fish &their sex organs in Rutilus f. Kutum along the southern coasts of the Caspian Sea. To this end, the fish and gonad samples of Rutilus f. kutum migrating to rivers & estuaries were collected & analyzed through sampling procedures based on fish gonad. Upon treating the samples with Bouin & the related preparations, (I.e. extraction of water, making from the sample them transparent, molding & doing them based on H&E method), , whereas Peterson correlation coefficient was applied for toxic variables. The results of the analysis shows that 45 percent of sampled fish with an average length of (349 58) mm weighing 564 334) were male and 54.4 were Females. The sexual maturity rate, as specified by the six stages analysis me Thad of Johnson’s (Johnson’s, 1970) in dictated the position of female in the stages: IV & V during March, April & June. 32% of female fish were in stage V & %68 in stage IV in March whereas the percentages of female fish in April was %87 in the stage V followed by %94 in the stage V during June.

Volume 8, Issue 2 (10-2009)
Abstract

Maize seedlings were treated with various concentrations of copper (25-100 µM) without EDTA and with EDTA for 120 hours. A sever and progressive decrease of root length and dry weight and an increase in K+ leakage with increasing Cu in nutrient solution was observed in the treated plants with Cu without EDTA. The roots accumulated significantly higher amounts of Cu than the shoot. With increasing Cu concentrations, amounts of Ca, Mg, K and Fe decreased in roots and in shoot. Application of EDTA with Cu caused increased dry weight and root length but decreased K+ leakage into nutrient solution. Application of EDTA increased Cu accumulation in roots but decreased it in shoot and caused a different effect on other minerals contents. Overall, EDTA could reduce copper toxicity in Maize seedlings.

Volume 8, Issue 3 (2-2009)
Abstract

The area under study is located in central Iran and 235 kilometers of south west of Tehran is a part of Qom quadrangle. Volcanic sequences, which constitute the most major parts of the outcrops in the region mainly, have seen in north eastern and east of Ashian. These volcanic rocks are included of andesite basalt, andesite, trachy andesite, dacite, rhyodacite and rhyolite that are emplaced during Eocene (middle Lutetian to late Lutetian) along the Oromieh-Dokhtar volcanic belt that divided to six members from E1 to E6 in Tafresh and Ashtian area. Plutonic rocks related to Oligo-Miocene. There are not any rocks older than Triassic in area under study. Volcanic rocks both pyroclastics and laves have covered the most of area and could be seen in the continental and marine so we can see ignimbrite and tuffs. Acid eruptions are more than basic in this area. Mineralogically, these rocks have plagioclase, alkali feldespar, quartz, clinopyroxene, amphibole, biotite and a lesser amount olivine. Plagioclases have zoning structure and amphibole crystals have opacite rimmed. This phenomenon shows that magma responsible for rocks had a high temperature. Geochemically, petrographically and petrologically studies based on major and trace elements and differentiation index versus SiO2 indicate that changes in the volcanic processes at the area are the result of magmatic crystallization and differentiation magmatic rocks magma of area under study is calc-alkaline and they belong to subduction. Using of petrological and tectonic setting diagrams indicate that these Eocene magmatic rocks are compared to calc-alkaline series of subduction orogenic andesitic belts. The rare and trace element patterns of thes rocks have investigated and the examples of anomalies are related to Sr and Nb. Also the study of trend show that the calc-alkaline magma has formed in the upper mantle. Similarities between volcanic and plutonic rocks in Ashtian area show that these rocks may be having the same origin.

Volume 8, Issue 3 (2-2009)
Abstract

Jahagh anticline in south of Kashan is host to the Silurian volcanic rocks at the base of Niure formation (with sandstone lithology).This area is located in the western edge of Central Iran zone. The volcanic rocks under study involved basalt until trachy basalt and contain Plagioclase. These rocks belong to alkali basalt to sub- alkali basalt field on the geochemical diagrams.The investigation of rare earth elements indicate garnet presence in the source with low partial melting degree. High Ti and Zr content in these rocks show that the magmatic series is alkaline- transitional. The geotectonic setting is intracontinental rift that follow the extension phases after Caledonian orogeny and creatie the deep faults in Iran cratonic crust. In all probability, Isfahan fault activation that is one of the old and basal faults in this area cause the eruption and volcanism at Silurian in this part of Iran.

Volume 8, Issue 4 (11-2010)
Abstract

Microalgae are cosmopolitan microorganisms and minerals are considered as limiting factors for growth of them. In the present study cyanobacteria were isolated and indentified and also the effect of different media on their growth was examined. Consequently, two new species of cyanobacteria belonged to the family of Oscillatoriaceae were isolated and reported for the first time from Tehran province. To this end, soil samples were collected from Tehran Province in summer 2008. Samples were cultured in BBM & N8 media to evaluate the effect of nutrients on the growth of microalgae. Isolation was carried out by several subcultures. Morphological indentification was done using systematics keys and partial sequencing of 16S rRNA was used for molecular identification. The results showed that two species were recorded from Tehran Province, Leptolyngbya sp. ISC 40 Gomont and Leptolyngbya sp. ISC 25 Gomont. The collected soil samples were analyzed physically and chemically. Results indicated that BBM medium was suitable for isolation and as indicated by infertility of cultured soils, two identified species are resistance to environmental factors.

Volume 8, Issue 4 (11-2010)
Abstract

Caprini is one of the largest sections belonging to the genus Astragalus with 280 species. Astragalus Sect. Caprini are revised. This section has 171 and 115 species in Flora Iranica area and Iran, respectively. During the work, plant specimens preserved in Ferdowsi University of Mashhad, Herbarium (FUMH) were indentified from different regions of Khorassan provinces. Also, distribution of regions in different parts of this section are presented. Based on this study, 37 species of this section are known in Khorassan provinces. A. kushkensis in Flora Iranica has been recorded from Turkmenistan and Afghanistan and is reported from NE. of Khorassan, Torbate – jam, Saleh Abad as a new record for the flora of Iran. This plant is glabrous and has 18 – 22 pairs of leaflets. Leaflets are narrowing ovate and glabrous. Distribution regions of these taxa in different parts of Khorassan province are given.
N Aliev, Mh. Fatehi, M Jahanshahi,
Volume 9, Issue 1 (10-2010)
Abstract

Some boundary value problems for the Cauchy-Riemann equation with non-local boundary conditions in several regions of plane have been investigated and solved by authors. In this paper, by making use of fundamental solutions of Cauchy-Riemann equations and by presenting analytic solutions to the above-mentioned boundary value problems, we try to present an analytic expression for the solution of Cauchy-Riemann equation in the first semi-quarter.

Volume 9, Issue 1 (10-2010)
Abstract

A direct method to determine numerical solutions of linear Volterra integro-differential equations is presented in this paper.. This method is based on block-pulse functions and its operational matrix. By using this approach, the integro-differential equation reduces to a linear lower triangular system of algebraic equations which can be solved easily. Some numerical examples are provided to illustrate accuracy and computational efficiency of the method. MSC: 45J05 41A30

Volume 9, Issue 1 (10-2010)
Abstract

In this note we introduce the notion of weak McCoy rings as a generalization of McCoy rings, and investigate their properties. Also we show that, if is a semi-commutative ring, then is weak McCoy if and only if is weak McCoy.

Volume 9, Issue 1 (10-2010)
Abstract

An efficient one-pot synthesis of 1,8-dioxo-octahydroxanthene is achieved through a condensation of arylaldehydes and 5,5-dimethyl-1,3-cyclohexanedione in the presence of N-bromosuccinimid. This method enjoys several advantages such as low cost, simple work up procedure and safe reaction conditions. Graphical Abstract Table 1. Optimization of reaction condition. Entry Amount of NBS Condition Yield (%)a 1 0 mol % Reflux/ethanol/20 h 0 2 2 mol % 50°C/ethanol/12 h tr 3 2 mol % Reflux/ethanol/14 h 15 4 5 mol % Reflux/ethanol/14 h 30 5 10 mol % Reflux/ethanol/14 h 55 6 15 mol % Reflux/ethanol/14 h 80 7 20 mol % Reflux/ethanol/14 h 94 8 20 mol % MW/DMAC/5 min 90 a Isolated yield.

Volume 9, Issue 2 (10-2010)
Abstract

In this research, ac measurements of copper phthalocyanine thin film using aluminium electrodes are investigated in the frequency range 102 to 105 Hz and within the temperature range frequency and the capacitance and dissipation factor(loss tangent) decrease with increasing relative importance of the hopping model and band theory in describing the film condution with regard to the operating conditions. It was observed that the band theory is dominant at high frequencies and high temperatures, whereas hopping model is dominant at low frequencies. The energy gap of CuPc was determined using dc measurements.

Volume 9, Issue 2 (10-2010)
Abstract

The most popular phenomenological approaches for investigating the decay channels of B meson is the hypothesis of factorization, which applies to certain two body semileptonic decays. This research utilizes the factorization method according to the colour transparency hypothesis. We use the factorization method for obtaining the b quark decay amplitudes for calculating the B mesons decays amplitudes. We use the factorization method for leptonic and semileptonic decays.

Volume 9, Issue 3 (10-2010)
Abstract

Several experiments have been performed during the last few decades to evaluate the responses of plants to enhanced solar UV radiation (UV-R) that may occur because of stratospheric ozone depletion. The objective of this study was to evaluate the effects of UV radiation on some anatomical and ultrastructural aspects of pepper plants (Capsicum longum L) in the greenhouse. Pepper plants were grown in a uniform environment and after 35 days they were exposed to UV-A and UV-C radiation for 15 and 8 days, respectively. The results indicated that the changes in root growth was not significant but the growth of shoot decreased in UV-R exposed plants and this reduction was significant in UV-C exposed plants. Leaf area was also reduced in UV-R exposed plants and this reduction was significant in UV-C exposed plants. The root diameter was not affected under UV treatment, but the stem diameter and leaf thickness were significantly increased in both UV-A and UV-C treatments. The number and size of stomata were also increased in UV-R exposed plants. At the ultrastructural level, it was found that the thylakoids of chloroplast were dilated and starch reduction was observed. UV treatment resulted in the formation of crystalline inclusion in the peroxisomes of the mesophyll cells. Formation of these crystals may be due to the increased activity of catalase, which is an antioxidant enzyme. The study shows that pepper plants are sensitive to UV-R and this finding provides insight into the structural and ultrastructural changes during UV exposure, and indicates the sensitivity of these plants to UV-C more than UV-A radiation.

Volume 9, Issue 4 (10-2010)
Abstract

Nickel is one of the essential elements (micronutrients) for plant growth. In this study, the effects of different concentrations of nickel, (0, 40, 80, 160, 320, 640 and 1280&mu M) and some environmental factors such as pH and Ca2+ concentration on the growth of seedlings of four wheat cultivars (Sardari, Zarrin, Alamout and C-73-20) were investigated. Moreover, the impact of high concentration of Ni on root sugar secretion has been assessed using sulphuric-phenol method .The results indicated that Alamout was more resistant than the other cultivars regarding to nickel stress. On the other hand, root and shoot tissues showed different growth responses to Ni and radical growth was more sensitive than shoot growth. Decreased pH increased the impact effect of nickel on shoot and root growth. Our study showed that increasing Ca2+concentration decreases Ni toxicity. Finally, Ni inhibited the leakage of soluble sugars from root tissue.

Volume 9, Issue 4 (10-2010)
Abstract

The effect of various CuCl2 concentrations at rosette stage on protein level, catalase and peroxidase activities of leaf and root of two canola cultivars were studied under greenhouse conditions. The experiment was conducted as factorial in completely randomized design with 4 replications and 4 treatments (0, 100, 300, and 500µM CuCl2). In general, protein concentration and catalaze and peroxidase activities were increased with increasing CuCl2 concentration. This enhance was more in PF cultivar than Hayola, and was more in root than leaf. Thus, it seems that PF cultivar has more ability in protein biosynthesis and antioxidant enzymes activation in compare with Hyola in stress conditions. Therefore, PF can be introduced as a cultivar with more tolerance to cupper stress, in compare with Hayola cultivar.
, , ,
Volume 9, Issue 4 (10-2010)
Abstract

The Ursolic Acid and Oleanolic Acid presented in apple peels have a potential antioxidant acivity. Antiprolifertive acivity of the triterpenoids against human liver cancer cells, breast cancer cells and colon cancer ells is evaluated. In this study, we have used Ursolic Acid and Oleanolic Acid which are predominant isolated triterpenoids of the apple peels.. The purpose of this study is to determine antimutation and anticarcinogen effect of Ursolic Acid and Oleanolic Acid against Sodium Azide mutagen substance by the use of Microsome and Ames test.
These substances were white powder and soluble in Acetone and bought from sigma company. The bacterium used in this test is a strain of Salmonella thyphimurium (TA100) that carries a selective mutation in its Histidine Operon. We also added Microsome to improve anticancer activity of this two triterpenoids. In this study, inhibition percentage from mutation was 83% for ursolic acid and 76.4 % for oleanolic acid in presence of Microsome ( and 77.6 % for Ursolic Acid and 69.8 % for Oleanolic Acid in absence of Microsome) . Therefore , presence of anti mutation Ursolic Acid and oleanolic acid along with mutagen substance, reduced quantity of back mutation and Inhibition over 40 % recommended as a powerful antimutation substance. Therefore, apple peel has large amount of active Phytochemicals, with Antimutation and Anticarcinogen activity and Ursolic Acid has more antimutation activity than Oleanolic acid

Volume 9, Issue 4 (10-2010)
Abstract

This study was performed to investigate the effects of ultraviolet light (UVC) on the third instar larvae of Drosophila melanogaster. To address such effects, double heterozygote larvae for two linked genes sepia and ebony (se e/++) were exposed to UV light at the wavelength of 254 nm in different exposure times (5-35 seconds). Our study showed that the UVC exposure induced a series of significant morphological abnormities in adult flies which had received radiation in their larval life-time. Short exposure times of UVC caused abnormalities in adult flies such as abdominal cuticular damages and abnormal legs and wings, but had no significant effect on the rate of gene recombination. Therefore, it seems the time of exposure which was used in this research affected some imaginal discs and histoblasts on the larvae.

Volume 10, Issue 1 (3-2010)
Abstract

One of the fundamental steps in management of drought involves identification and frequency analysis of its properties, e.g. duration and severity of drought. Regarding the high correlation among these factors, one must use a method that shows the relation and effects of these factors on drought analysis. Copula functions can be used to represent the dependency structure of several variables through a model. In this paper, we introduce the appropriate copula families for modeling drought phenomenon modeling. Then, their parameters would be estimated by maximum likelihood and Empirical Bayes methods and the most appropriate copula function for determining bivariate distribution of duration and severity of drought in Tehran stations is determined. Next, this copula function is used to model the drought phenomenon of Tehran for the period of 37 years from 1348 until 1384, Finaly the application of this model is represented in water supply management.
Nasrollah Iranpanah, Morteza Mokhtari Moghadam,
Volume 10, Issue 1 (3-2010)
Abstract

Shewhart control charts are widely accepted as standard tools monitoring manufacturing statistical processes. The control charts have not applied, when the process distribution is not normal. The bootstrap is one of the resampling methods that can be used in statistical quality control without normality assumption. In most of papers, only the percentile bootstrap confidence interval is used for control limits. In this paper, we apply percentile bootstrap, bootstrap-t, bias corrected accelerated (BCa) and approximate bootstrap confidence interval (ABC) for mean control limits of statistical process. Then, the bootstrap confidence intervals are used and compared for mean control limits in simulation study. Finally, the bootstrap control limits are used for mean of CO2 data in Isfahan Zamzam factory.
N Abrari,
Volume 10, Issue 2 (2-2010)
Abstract

The study of planktonic foraminifera of the Gurpi Formation in southwest of Firozabad(Aghar anticline) area led to recognition of eight biozones that include: Dicarinella asymetrica Zone (Santonian to Earliest Campanian), Globotruncanita elevata Zone (Early Campanian), Globotruncana ventricosa Zone (Mid to Late Campanian), Radotruncana calcarata Zone (Late Campanian), Globotruncanella havanensis Zone (Late campanian), Globotruncana aegyptiaca Zone (Late to Latest Campanian), Gansserina gansseri Zone (Latest Campanian to Early Maastrichtian), Contusotruncana contusa and Racemiguemblina fructicosa Zone (Early to Late Maastrichtian). In study area, the Gurpi Formation overlies the Ilam Formation with erosional disconformity and is overlain by the Pabdeh Formation with erosional disconformity. Based on distribution of morphotype groups of planktonic foraminifera, planktonic foraminifera per bentic foraminifera ratio(P/B) and content of carbonate, seven third-order sequences are recognized. Sequence boundries of Gurpi Formation with Ilam Formation at the base and with Pabdeh Formation at the top, are SB1, but other sequence boundries are SB2.

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