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1 - Phonon-induced superconductivity and physical properties in intercalated fullerides Rb3C60
Dinesh Varshney Rajendra Jain Namita SinghAbstractThe nature of electron pairing mechanism and physical properties leading to superconducting state and normal state resistivity in alkali metal (Rb) intercalated fullerenes are explored. Keeping in mind that free electrons in lowest molecular orbital are coupled چکیده کاملAbstractThe nature of electron pairing mechanism and physical properties leading to superconducting state and normal state resistivity in alkali metal (Rb) intercalated fullerenes are explored. Keeping in mind that free electrons in lowest molecular orbital are coupled with inter-molecular phonons, the coupling with inter-molecular phonon leads to transition temperature (Tc) of about 4.17 K. The electrons also couple with the intra-molecular phonons. Within the framework of strong coupling theory, Tc is estimated at 34 K. The carbon isotope effect exponent, the energy gap ratio, influence of pressure and volume on Tc, and thermodynamical parameters describing the superconducting state confer that Rb3C60 as s-wave superconductor. Estimated contribution to resistivity using scattering with inter- and intra-molecular phonon, when subtracted from single crystal data, infers quadratic temperature dependence over most of the temperature range and is attributed to electron–electron inelastic scattering. Both low frequency intermolecular and high frequency intra-molecular phonons have significant bearing in Rb3C60 superconductor. پرونده مقاله -
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2 - Enhancement of charge breeding efficiency for rare isotope beam with the control of magnetic field profile and electron beam energy in EBIS
J. W. KimAbstractThe magnetic field in the ion trap of electron beam ion source (EBIS) determines the current density of electron beam and thus the depth of trap potential, which affects the charge breeding efficiency to desired charge state. An EBIS charge breeder has been cons چکیده کاملAbstractThe magnetic field in the ion trap of electron beam ion source (EBIS) determines the current density of electron beam and thus the depth of trap potential, which affects the charge breeding efficiency to desired charge state. An EBIS charge breeder has been constructed to be used for the Rare Isotope Science Project in Korea. A 6 T superconducting solenoid is used for the trap, and uniform magnetic field is extended with correction coils at the ends. The effect of field uniformity on the electron current density is evaluated using TRAK, and it is shown sizable improvement in the charge breeding efficiency for rare isotope beams can be obtained by elaborate magnetic design. Furthermore, the electron beam energy affects the ionization efficiency. The electron energy is often reduced in the trap for optimal matching with charge striping cross section. However, virtual cathode formation can appear in the process of energy reduction. Maximum beam currents limited by electron energy are studied analytically and by TRAK simulation in the view of improving the charge breeding efficiency. پرونده مقاله -
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3 - Origin and development of Skarn-Forming fluids from the Band-e-Narges Skarn Iron ore, Central Iran
Maliheh Nazari Mohammad Lotfi Nematallah Rashidnejad omran Nima NezafatiThe Band-e-Narges magnetite deposit is located in central part of Urumieh–Dokhtar Magmatic Arc (UDMA). Wide I-type calk-alkaline and alkalin magmatic activity in the Koh-e- Latif region has been reported due to Eocene intrusive processes in UDMA. The iron ores are چکیده کاملThe Band-e-Narges magnetite deposit is located in central part of Urumieh–Dokhtar Magmatic Arc (UDMA). Wide I-type calk-alkaline and alkalin magmatic activity in the Koh-e- Latif region has been reported due to Eocene intrusive processes in UDMA. The iron ores are hosted by Cretaceous limestone intruded by granite and granodiorite units. Genetic model of this deposit was determined using petrological, stable isotope, fluid inclusion and mineralographical data. Five stages of paragenesis were observed in terms of mineralization in this area: prograde stage, retrograde stage, sulfide-quartz stage, carbonate stage and oxidation stage. According to mineralogy and geochemistry studies, formation of the skarn has resulted from a hydrothermal fluid changing carbonate units to hydrosilicate minerals. The ore minerals showed magnetite features with slight chalcopyrite and pyrite. The δ34S values ranged from +3.31 to +6.29 for the early retrograde stage pyrite and from +5.51 to +7.1 for that of late retrograde stage pyrite + anhydrite pairs. All the δ34S values of pyrite and anhydrite + pyrite were positive with a magmatic sulfur origin in these deposits. Fluid inclusions were observed according to petrographic and microthermometric inclusions within garnet, quartz, and calcite minerals at various stages. Due to high temperature (414 -448 ºC ) and middle salinity (up to 13.186 wt% NaCl) of fluid inclusions in prograde skarn-stage (garnet), the fluid inclusions showed a composition related to magmatic fluids following reaction with calcareous wall rock and fluid inclusions were trapped at pressures of 400 -500 bars, corresponding to depths of 1.5 -2 km in prograde stage. Fluid inclusions in quartz had moderate temperatures (152-303 ºC) and low salinity (7.9-11.3 wt% NaCl) indicating quartz-sulfide stage and late retrograde stage. The presence of fluid inclusions with moderate homogenization temperature (303 ºC) suggested that reboiling has occurred under hydrostatic pressure of 150-250 bars, equivalent to a depth of 1 -1.5 km in the late retrograde skarn and quartz-sulfide stages. Fluid inclusions in calcite had moderate temperatures (160 -287ºC) and low –to- high salinities (0.406-23wt% NaCl). A greater number of the fluid inclusions in the Band-e-Narges deposit had salinity (0.4-23.74 wt% NaCl) and homogenization temperatures (152-448 ºC) showing them as a moderate-high temperature and low–to-high salinity type of deposit. A decline in temperature and variation in salinity documented for the Band-e-Narges deposit would cause a notable decrease in Fe solubility and ore precipitation. Fluid compositions indicated that ore-forming fluid had a high fO2 value and rich Fe concentration in the early stage, while having relatively lower fO2 value and poor Fe concentration in the retrograde and sulfide stages. The data obtained from geology, mineralogy, geochemistry, salinities, and homogenization temperatures of the fluid inclusion populations at the Band-e-Narges iron deposit followed a model of boiling as a result of decrease in pressure, mixing, and cooling. پرونده مقاله -
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4 - Petrochemical Characteristics of Neogene and Quaternary Alkali Olivine Basalts from the Western Margin of the Lut Block, Eastern Iran
S. Saadat M. H. Karimpour Ch. SternThe Nayband strike-slip fault forms the western margin of the micro-continental Lut block in Eastern Iran. Neogene and Quaternary mafic volcanic rocks collected near Tabas, along the northern part of the fault (NNF; 15 Ma), and further to the south, along the middle par چکیده کاملThe Nayband strike-slip fault forms the western margin of the micro-continental Lut block in Eastern Iran. Neogene and Quaternary mafic volcanic rocks collected near Tabas, along the northern part of the fault (NNF; 15 Ma), and further to the south, along the middle part of the fault (MNF; 2 Ma), are within-plate sodic-series alkali olivine basalts with high TiO2 and up to >16% normative nepheline. Their high MgO, Ni and Cr contents indicate that they crystallized from relatively primitive magmas. Their low La/Nb and Ba/Nb ratios are similar to oceanic island basalts (OIB) and unlike convergent plate boundary arc basalts (IAB). These alkali olivine basalts show enrichment in LREE relative to HREE and limited variation in Sr, Nd and Pb isotopic values which all plot in the range of OIB. Ce/Pb (>39), Nb/U (44-120) and P2O5/K2O (~0.4) ratios suggest that crustal contamination was not significant for MNF basalts. The data may be interpreted as indicating the participation of upwelling mantle asthenosphere and the deeper continental mantle lithosphere in the generation of these basalts. They formed by generally low, but variable degrees of partial mantle melting, which decreased with time from 15 Ma NNF relative to2 Ma MNF basalts. The small volume of melts that formed the MNF basalts rose to the surface along the deep Nayband strike-slip fault with no interaction with the continental crust. The larger volume of NNF basalts interacted to some degree with the crust and are associated with basaltic andesites and andesites. پرونده مقاله -
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5 - مطالعه و ببرسی ایزوتوپ های استرانسیوم-نئودیمیوم سنگ های آتشفشانی شمال میمه،استان اصفهان
محمد علی علی آبادی مهناز خدامیسنگهای اتشفشانی به سن نسبی پلیوسن و جوانتر در 120 کیلو متری شمال غرب اصفهان برونزد دارند.و متعلق به نوار اتشفشانی ارومیه-دختر در پهنه ایران مرکزی می باشد.مطالعات پتروگرافی و ژئو شیمیایی نشان میدهد که جنس این سنگها ریوداسیت،داسیت و آندزیت و تراکی آندزیت است و متعلق به سر چکیده کاملسنگهای اتشفشانی به سن نسبی پلیوسن و جوانتر در 120 کیلو متری شمال غرب اصفهان برونزد دارند.و متعلق به نوار اتشفشانی ارومیه-دختر در پهنه ایران مرکزی می باشد.مطالعات پتروگرافی و ژئو شیمیایی نشان میدهد که جنس این سنگها ریوداسیت،داسیت و آندزیت و تراکی آندزیت است و متعلق به سری کالکوآلکالن می باشند.جهت تفسیر نهایی پتروژنر و محیط تکتونیکی این سنگها از ایزوتوپ های پرتو زاد SRوNd استفاده شده است بیشتر داده های ایزتوپی نشان دهنده یک منشا نزدیک به آرا یه گوشته و متمایل به گوشته غنی شده نوع EMII در محیط فرورانش برای ماگمای سازنده این سنگ هاست که به ماگماتیسم کمان قاره ای شباهت دارد.غنی شدگی می تواند ناشی از دخالت پوسته یا متاسوماتیسم منشا در اثر سیالات ناحیه فرو رانش باشد.البته عدم افزایش محسوس در ایزوتوپ های نئودیمیوم و کاهش در ایزوتوپ های استرانسیم نشان دهنده عدم الودگی مذاب با لیتوسفری است که از میان آن عبور کرده است. پرونده مقاله -
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6 - Review Paper: Bioarchaeology; Archaeological study via the biological perspective
Najmeh Hadizadeh ShiraziBiological samples such as bones, tooth, and hair obtained from archaeological excavations are mainly used for dating measurements. However, these findings provide valuable information about the diet, lifestyle or migration, and genetic interaction of communities, and d چکیده کاملBiological samples such as bones, tooth, and hair obtained from archaeological excavations are mainly used for dating measurements. However, these findings provide valuable information about the diet, lifestyle or migration, and genetic interaction of communities, and disease because the biochemical content of biological tissues such as bones, teeth, and hair changes under the influence of the lifestyle of the past population. Therefore, it seems that human remains' biochemical, microscopic, and histological studies could be advantageous for clarifying the dark events of the past societies. Bioarchaeology, as an interdisciplinary science, assesses the historical-cultural relationships in ancient samples and human remains like hair, bone, or tooth by biological tools and techniques. In this science, the biological data of specimens are combined with archeological information to obtain a more accurate sociology of past civilizations. The purpose of the present review article is to familiarize archeology researchers with the usual methods in bioarchaeological studies. پرونده مقاله -
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7 - نحوه تشکیل کانسار باریت آب ترش،استان کرمان،با نگرشی بر ژئوشیمی عناصر نادر خاکی و ایزوتوپهای پایدار اکسیژن و گوگرد
حسین کلانترهرمزی فرهاد احیاء قدرت الله رستمی پایدار سارا ملکی خیمه سریباریت می تواند در محیط های مختلف زمین شناسی تشکیل شود، به طوری که در طیف گسترده ای از انواع کانسارها یافت می شود.برای تعیین منشأ و شرایط فیزیکی و شیمیایی تشکیل کانسار باریت آب ترش، مطالعه جامعی با استفاده از روشهای پتروگرافی، ژئوشیمی عناصر نادر خاکی و ایزوتوپ های اکسیژ چکیده کاملباریت می تواند در محیط های مختلف زمین شناسی تشکیل شود، به طوری که در طیف گسترده ای از انواع کانسارها یافت می شود.برای تعیین منشأ و شرایط فیزیکی و شیمیایی تشکیل کانسار باریت آب ترش، مطالعه جامعی با استفاده از روشهای پتروگرافی، ژئوشیمی عناصر نادر خاکی و ایزوتوپ های اکسیژن وگوگرد انجام شد.کانی سازی باریت در آب ترش به صورت یک رگۀ چینه کران در واحدهای سنگی کربناتی سنونین رخ می دهد. باریت با کوارتز و مقادیر جزیی مالاکیت، کریزوکولا، اکسیدها و هیدروکسیدهای آهن و منگنز، گالن، آزوریت، فلوریت، پیریت و بورنیت همراه است. سنگ های میزبان برشی و سیمان شده توسط باریت حاکی از یک منشأ اپی ژنتیک برای کانی سازی باریت است. مقادیر مجموع عناصر نادر خاکی در نمونه های باریت بسیار کم است (56/14-32/5 ppm)، و الگوهای هنجار شده با کندریت غنی شدگی عناصر نادر خاکی سبک نسبت به عناصر نادر خاکی سنگین را نشان می دهند.مقادیر کم مجموع عناصر نادر خاکی و نسبت های عنصری عناصر نادر خاکی (Ce/La؛ (La/La*)N و (Gd/Gd*)N) نشان می دهد که آب دریا با ماهیت ژئوشیمیایی بسیار تغییر یافته (آب های فسیلی) به عنوان سیال ته نشست دهندۀ باریت عمل کرده است.مقادیر δ18O و δ34S در نمونه های باریت (به ترتیب 1/11+-4/10+ ‰ و 8/27+-3/27+ ‰) و مقادیر δ34S در گالن (3/6+ و 9/7+ ‰) نشان می دهد که سولفات (و در نتیجه گوگرد) از آب های فسیلی حمل کنندۀ سولفات و یا تبخیری ها منشأ گرفته است. کاهیدگی ترموشیمیایی سولفات (TSR) محتمل ترین مکانیسم برای تشکیل گوگرد کاهیده در گالن است.در این مطالعه، کانسار آب ترش به عنوان یک کانسار باریت وابسته به ساختار(ناپیوستگی) طبقه بندی می شود. پرونده مقاله -
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8 - Stable Isotope Application in Animal Nutrition Science
و. جعفری م. جعفری ل. روسی ا. کالیتزا م.ل. کوستانتینیThe application of stable isotope analysis (SIA) has become a standard scientific approach in Agricultural and Ecological researches and, more in general, in several disciplines such as biology, botany, zoology, organic chemistry, climatology, and nutrition. The main ob چکیده کاملThe application of stable isotope analysis (SIA) has become a standard scientific approach in Agricultural and Ecological researches and, more in general, in several disciplines such as biology, botany, zoology, organic chemistry, climatology, and nutrition. The main objectives of this paper are (1) to provide a simple definition of stable isotopes and (2) to illustrate analytical measurement methods and general applications in animal nutrition. The stable isotopes of carbon (δ13C) and nitrogen (δ15N) represent powerful tools to evaluate the trophic preferences of organisms and their trophic position. In association with Bayesian Mixing models, stable isotopes also enable the description of trophic links between species and, thus, of complex food webs. Stable isotope data should be complemented with additional dietary data on feeding behavior to provide information regarding the transfer of energy or nutrients. Nowadays, stable isotope analysis is employed to address animal and human diets around the world. پرونده مقاله -
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9 - Geochemistry of Neoproterozoic cap carbonate of banded iron-formation of the Rizu serie in Jellal abad Zarand
Mehdi Kianian Ahmad Khakzad Iraj Rasa Mansor AbediniIn the study area, the various of cap carbonates include medium to coarse (saddle dolomite) grains of dolomites, are situated uppermost of sequence of Rizu Formation. The sequence of Rizu serie contains of various lithology, quartzite sandstone, turbidities (Greywacke) چکیده کاملIn the study area, the various of cap carbonates include medium to coarse (saddle dolomite) grains of dolomites, are situated uppermost of sequence of Rizu Formation. The sequence of Rizu serie contains of various lithology, quartzite sandstone, turbidities (Greywacke) with association of ore minerals(Magnetite- Hematite- Jasper) , in the form of Banded iron- Formations, (BIFs) .The existence of dropstones with heterogeneous grains (Diamictite) within fine matrix of carbonate are the indicators for glaciations episodes, which are located under the cao carbonate. Chemical analyses of carbonates showed that the δc13 ,δo18 values of carbonates in area are low , ranging From- 2.65 to -6.79 per mil versus (PDB), and- 6.48 to – 15.21permil (PDB), respectively, whereas the excursion wide range of 18-oxygen isotope reflect the alteration and diagenetic processes. The high concentration of iron and manganese and high index of alteration (Fe/Sr=720 or Mn/Sr=52) is associated by decreasing 13-carbon isotope. The δc13 depleted carbonates reflect climate changes from glacial (Icehouse) to greenhouse conditions that deposited during sea- level rise after retreating and deglaciation after math global glaciations snowball earth. پرونده مقاله -
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10 - The non-sulfide ore Formation conditions of Ravar-Bafgha rea, findings of carbon and oxygen stable isotopes
Ali Amiri Iraj RassaThe carbonate-hosted zinc-lead deposits of Ravar-Bafgh area mainly contain non-sulfide ore. In this article, we have studied the variations of carbon and oxygen isotopic ratios from separated non-sulfide minerals. The range of δ13CPDB in the smithsonite varies fro چکیده کاملThe carbonate-hosted zinc-lead deposits of Ravar-Bafgh area mainly contain non-sulfide ore. In this article, we have studied the variations of carbon and oxygen isotopic ratios from separated non-sulfide minerals. The range of δ13CPDB in the smithsonite varies from -1.456 to -7.248‰ and shows a good congruency with meteoric CO2. In the hemimorphite, 13CPDB values vary from -17.871 to -23.554‰ and show high enrichment of light carbon isotope. Vein-type aragonite associated with non-sulfide ore is formed under the same conditions as the smithsonite, but the calcite mineral associated with sulfide ore is formed under the same conditions as the limestone. The range of 18OSMOW and 18OPDB isotopic ratios is studied in the mentioned minerals. In the smithsonite, the δ18OSMOW values vary from +21.821 to +26.445‰, the values of δ18OPDB vary from -6.882 to -8.768‰, the values in the hemimorphite vary from +16.263 to +19.580‰ and from -10.876 to -14.160‰ for 18OSMOWand 18OPDB respectively. These values show that the non-sulfide minerals of these deposits are formed during the weathering of exposed sulfide ore and the fluids responsible for these processes are descending meteoric waters with minor amount of pore waters entrapped in the porosity of the carbonate host rocks. پرونده مقاله -
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11 - Jurassic Pb-Zn mineralization at Baba Gholleh
Farhad Ehya Mohammad Lotfi Iraj RasaA complete study including field geology, petrography, fluid inclusions, and trace- and rare-earth element geochemistry, and lead and sulfur isotope studies has been carried out on the Baba Gholleh Pb-Zn prospect located in the Sanandaj-Sirjan tectonic zone of western I چکیده کاملA complete study including field geology, petrography, fluid inclusions, and trace- and rare-earth element geochemistry, and lead and sulfur isotope studies has been carried out on the Baba Gholleh Pb-Zn prospect located in the Sanandaj-Sirjan tectonic zone of western Iran. Ore-host rock relationships and petrographic studies show that Baba Gholleh Pb-Zn prospect is a vein-type deposit in which ore minerals occur predominantly with quartz veins and flat lenses, interbedded in the metamorphic host rocks. Galena and sphalerite are dominant ore minerals accompanied by quartz and calcite gangue minerals. Fluid inclusion studies suggest that ore-forming fluid has a low to moderate salinity. The temperatures of homogenization range mostly between 135 °C and 200 °C, corresponding well with the metamorphic temperatures of the host rocks. This temperature range also occurs in the temperature range of the basinal fluids, but the salinity of the ore-forming fluid is slightly less than that of basinal fluids, resulting from interference of meteoric waters. Geochemistry of trace elements points out that the host rocks are anomalously enriched in Zn and Pb, hence they could provide ore constituent metals. REE profile in mineral sphalerite reveals that these elements were leached from host rocks in low temperature conditions through fluid-rock interaction. Sulfur isotope composition of coexisting galena and sphalerite indicates that deposition of these minerals occurred in disequilibrium conditions, resulting from low total concentration of H2S in ore-forming fluid and rapid rates of sulfide deposition. Sulfur in sulfide minerals derived possibly from metamorphic host rocks. Lead isotopic studies indicate that the lead in galena was derived from an upper crustal source with higher 238U/204Pb ratio than the average for continental crust. The Pb-isotope model ages for mineralization, range from 270 to 472 Ma (average value is 371±100 Ma), indicate a Middle Ordovician to Lower Permian age. These Pb isotope model ages are not in accordance with the geological data which indicate a Post-Middle Jurassic age for mineralization. پرونده مقاله -
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12 - Climatic and Environmental Reconstruction Based on Stable Isotopes of Parishan Lake (Iran)
D. Noorollahi H. Lashkari M. Amirzade Gh. Azizi S. SharafiThe isotopic documents of lake deposition are suitable potential means for studyingthe intercontinental, environmental and climatic conditions. In order to study theenvironmental and climatic conditions of Parishan area in Fars province in Holocene, a Corewas taken with چکیده کاملThe isotopic documents of lake deposition are suitable potential means for studyingthe intercontinental, environmental and climatic conditions. In order to study theenvironmental and climatic conditions of Parishan area in Fars province in Holocene, a Corewas taken with the length of 2m from the Parishan lake sediment. From this core, kernel timeseries was provided from documents of carbon and oxygen isotopes. Results show that duringthe study period, climatic changes because gradual increasing in the value of ∂O18carb. Thisrepresents a weak dryness process in the area up to now. Contrary to this, carbon isotopedocuments during the study period show the more vigorous changes. Variability of ∂C13carbvalues during the study period is known as the result of changes in the value of evacuation ofunderground waters to the lake. As it is observed in the process at ∂O18carb throughout thestudy period, ∂C13carb values have an increasing process, yet the observed changes in ∂C13carbvalue are more vigorous than ∂O18carb and it seems that variation of underground waters wasnot in complete harmony with dryness process of the area. It seems that achievement ofunderground waters around the lake in the form of well and aqueduct is the intensify factorfor the reduction of underground inputs to the lake. پرونده مقاله
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