modern research physics

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توده های گرانیتی منطقه زریگان و چاه چوله در شمال بافق، جنوب شرقی نقشه 1:250000 اردکان واقع شده (شکل 1)، جزیی از خرده قاره ایران مرکزی محسوب می شوند. ترکیب سنگ شناسی این توده ها، از آلکالی فلدسپار گرانیت تا سینو- مونزو گرانیت نوسان دارد. آنها از نوع گرانیت های لوکوکرات و ساب ولکانیک، با کانی شناسی عمدتاً کوارتز- فلدسپاتی، و فقیر از کانیهای مافیک هستند. انواع بافتهای ماگمایی، دگرشکلی، متاسوماتیک و دگرسانی، گرانوفیری، گرافیک، میلونیتی و کاتاکلاستی، میرمکیت، پرتیتی و جانشینی در آنها دیده می شود. از نظر ژئوشیمیایی، توده های مورد بحث، ویژگیهایی از سریهای کالکوآلکالن تا آلکالن، پرآلومینI-type و محیط تکتونیکی کمان ماگمایی را نشان می دهند. در نمودارهای تغییرات عناصر نیز، بستگی به تمایلات ذاتی، پویایی و مراتب سازگاری و ناسازگاری عناصر، رفتارهای متفاوتی دیده می شود که گویای تاثیر فرآیند تفریق و تبلور و متاسوماتیسم، هر دو، بر توده های مذکور است. شواهد صحرایی، سنگ شناختی و ژئوشیمیایی، در توده های گرانیتی زریگان و چاه چوله حاکی از آن است، که لااقل بخشی از این توده ها، بویژه گرانیت زریگان، از طریق متاسوماتیسم و فرآیندهای تفریق گرمابی از سنگهای مافیک قبلی (توده های دیوریتی و گابرویی) تشکیل شده است و حتی پس از آن نیز به نحوی گسترده تحت تاثیر این فرآیندها واقع شده اند. مقایسه این توده ها، با معیارهایی که برای تمایز گرانیت های ماگمایی و متاسوماتیک ارائه شده، نشان داده که این توده ها، ضمن شباهت هایی با برخی از توده های شاخص ماگمایی، بیشترین شباهت را به گرانیت نوع متاسوماتیک یا
E- type دارند.

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Aquatic ecosystems are the main biotic ecosystems that contain variety of plant species and their destruction result in the reduction of plant species diversity. In the present investigation, species diversity of aquatic plants in permanent, seasonal, forest wetlands and ricelands of the west and east of Mazandaran province was determined. First, 30 habitats were determined on the map and the total 161 samples, based on systematic-random sampling, were established. 126 species of aquatic plant of the habitats were collected and the cover of each species ,based on the area of quadrate that accupied by plants, was recorded. The results showed that species diversity of aquatic plants in the west and east is governed by the moisture gradient. Based on De Martonne classification system of climate, the west and east of Mazandaran province have wet and mediterranean climate, respectively. Therefore, the condition for the growth of aquatic plants in the west is more appropriate than in the east. Species diversity of wetlands and ricelands in the west was higher than that in the east. In this study, classification system of den Hartog & Veld for aquatic plants that classify them as hygrophytes, real aquatic and wetland species was applied and diversity indices for all three categories were calculated. The results revealed that diversity of hygrophytes is the highest among them and the real aquatic plants have higher species diversity than wetlands. T-test, based on Shannon index, showed significant differences between diversity of the west and east as well as between three group of macrophytes (P<0.05).

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In the northern hillside of Central Alborz, in south Marzanabad, there are outcrops of basic volcanic rocks which attributed to Cretaceous time .In this study, effective processes on evolution of these volcanic rocks are surveyed to add on our knowledge about Mesozoic magmatisim in Central Alborz. Based on petrographical and geochemical studies, south Marzanabad basic rocks could be classified into 2 groups of basalt and andesite basalt. Geochemical diagrams imply that the magma nature is alkaline and generated in intracontinetal extensional environment. Microscopic studies, mineral chemical composition and the observed trends in geochemical diagrams of whole rocks, all are inline with fractional crystallization as a main magmatic process. Fractionation began with crystallization of olivine and pyroxene and minor plagioclase in basalts and continued with crystallization of clinopyroxene and plagioclase in andesite basalt. In addition to petrographical, mineralogical and chemical evidences, the occurrence of fractional crystallization process is confirmed by the geochemical modeling with Melts software which also let us to reconstruct the condition of fractionation process. Based on the fractional crystallization modeling in south Marzanabad basic volcanic rocks, basalts are generated by 40 percent of fractional crystallization from primary magma. Basaltic andesites also produced after the fractionation of basalts, during 70 percent fractional crystallization from the same magma. Olivine thermobarometric studies also confirm the accuracy of data which is obtained by the Melts software.

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Linking between geographic information systems and decision making approach own the invention and development of spatial data melding methods. Data melding methods combine the data, to achieve a better result and their aim is, to detect the information available in the data set in order to enhance the ability of interpreting data and increase the accuracy of the data analysis. In this paper, Bayesian melding method has been studied for combination of measurements, outputs of deterministic models and kriging methods. By spatial Bayesian melding and kriging an attempted is made to spatial prediction of ozone data in Tehran and results are validated and compared using the mean square error criterion.

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In order to increase public health many study have been performed with adding probiotic bacteria in dairy products. In this filed on of the most critical problem is unfavorable taste and aroma produced by probiotic bacteria. So isolation probiotic bacteria from traditional dairy product could solve this problem. A rapid screening method is used to isolate acid tolerant bacteria from 30 different fermented dairy products After enrichment samples in MRS broth followed acid stressing (pH=2.5) different colony were selected on MRS agar, avoiding preliminary time consuming isolation steps. All the isolates were examined by microscopy, gram staining and catalase reaction. Fifty-eight isolates were selected and defined as lactobacillus SPP. The screening at low pH bile salt led to the selection of 19 resistant isolates. Cholesterol assimilation determined by difference in cholesterol content in the medium before and after the incubation period, showed that all lactobacilli strains were able to assimilate cholesterol at varying levels ranging from 54 to 266 μg/ml .Most cholesterol assimilation were seen in L.farieminis ,L. planetarium ,L.alimentarium ,L.casei, L. acidophilus isolated from yogurt and cheese of lighvan region. These data showed yogurt and cheese of lighvan region have probiotic potential.

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Shekarnab intrusion is a part of an extensive magmatism in the Central Alborz Tectonic Zone of Iran. This intrusive body, which is mostly composed of monzonitic, gabbroic and syenitic lithologies, was intruded within green tuffs of the Karaj formation. These plutonic rocks show geochemical alkaline-potassic affinity and in the case of aluminum saturation index, they could be classified as meta-aluminous rocks. These rocks show Nb negative anomaly, enrichment of LILE and are depleted in HFSE. The spider and discrimination diagrams demonstrate that the parent magma of the plutonic intrusion could be related to a subduction zone and have emplaced in an active continental margin. Based on geochemical analysis of trace and major elements, as well as field and petrographical studies, it could be suggested that crystal differentiation has played an important role in lithological diversity of this intrusive body.

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