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Chemical, isotopic and amino acid composition of Mukundpura CM2.0(CM1) chondrite: Evidence of parent body aqueous alteration

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Geoscience Frontiers 2019年第2期10卷 495-504页

作者： N.G.rudraswami A.K.Naik r.P.Tripathi N.BhANDari S.G.Karapurkar M.Shyam Prasad E.v.S.S.K.Babu u.v.r.vijaya sarathi National Institute of Oceanography (Council of Scientific and Industrial research) 78 BGKT Extension Science and Spirituality research Institute National Geophysical research Institute (Council of Scientific and Industrial research) Indian Institute of Chemical Technology (Council of Scientific and Industrial research)

The carbonaceous chondrites are intriguing and unique in the sense that they are the only rocks that provide pristine records of the early solar nebular processes. We report here results of a detailed mineralogical, chemical, amino acid and isotopic studies of a recently observed fall at Mukundpura, near Jaipur in rajasthan, India. Abundance of olivines in this meteorite is low and of serpentine minerals is high. FeO/SiO_2 = 1.05 in its Poorly Characterized Phases(PCP) is similar to that observed in other CM2.0 chondrites. The water content of ～9.8 wt.% is similar to that found in many other CM *** examination of matrix shows that its terrestrial weathering grade is WO but aqueous parent body alteration is high, as reflected in low abundance of identifiable chondrules and abundant remnants of chondrules(～7%). Thus, most of the chondrules formed initially have been significantly altered or dissolved by aqueous alterations on their parent bodies. The measured bulk carbon(2.3%) and nitrogen content and their isotopic(δ^(13)C =-5.5‰, δ^(15)N = 23.6%0) composition is consistent with CM2.0 classification probably bordering CM1. Several amino acids such as Alanine, Serine, Proline, valine, Threonine,Leucine, Isoleucine, Asparagine and Histamine are present. Tyrosine and Tryptophan may occur in trace amounts which could not be precisely determined. All these data show that Mukundpura chondrite lies at the boundary of CM2.0 and CM1 type carbonaceous chondrites making it one of the most primitive chondrites.

关键词： Carbonaceous chondrite Mukundpura CM Isotope Amino acid

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Celiac disease:diagnostic criteria in progress

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Cellular & Molecular Immunology 2011年第2期8卷 96-102页

作者： u volta v villanacci Department of Clinical Medicine St Orsola-Malpighi University HospitalBolognaItaly Department of Pathology Spedali CiviliBresciaItaly

until a few years ago,celiac disease(CD)was thought to be a rare food intolerance that was confined to childhood and characterized by severe malabsorption and flat intestinal ***,CD is regarded as an autoimmune disorder that is common in the general population(affecting 1 in 100 individuals),with possible onset at any age and with many possible *** identification of CD is challenging because it can begin not only with diarrhea and weight loss but also with atypical gastrointestinal(constipation and recurrent abdominal pain)and extra-intestinal symptoms(anemia,raised transaminases,osteoporosis,recurrent miscarriages,aphthous stomatitis and associated autoimmune disorders),or it could be completely *** the last 20 years,the diagnostic accuracy of serology for CD has progressively increased with the development of highly reliable tests,such as the detection of IgA tissue transglutaminase and antiendomysial and IgG antideamidated gliadin peptide *** routine use of antibody markers has allowed researchers to discover a very high number of‘borderline’cases,characterized by positive serology and mild intestinal lesions or normal small intestine architecture,which can be classified as potential ***,it is evident that the‘old celiac disease’with flat mucosa is only a part of the spectrum of *** is possible that serology could identify CD in its early stages,before the appearance of severe intestinal *** cases with a positive serology but with mild or absent intestinal lesions,the detection of HLA-DQ2 and HLA-DQ8 can help reinforce or exclude the diagnosis of gluten sensitivity.

关键词： celiac disease clinical presentation diagnostic criteria histology,genetics serology

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Effect of exhaust gas recirculation and ethyl hexyl nitrate additive on biodiesel fuelled diesel engine for the reduction of NOx emissions

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Frontiers in Energy 2012年第3期6卷 304-310页

作者： K. vENKATESWArLu B. S. r. MurTHY v. v. SuBBArAO K. vijaya KuMAr Mechanical Engineering Department K.L University Guntur 522502India Mechanical Engineering Department Q.I.S College of Engineering and Technology Ongole 523272 India Mechanical Engineering Department J.N.T.U Kakinada Kakinada533033 India

Cetane improvers reduce the ignition delay, which in turn reduces the combustion temperatures thereby reduce NOx emissions. Exhaust gas recirculation （EGr） proved to be an effective way to reduce the NOx emissions. In this present experimental work, a combination of exhaust gas recirculation and cetane improver ethyl hexyl nitrate （EHN） is used to investigate the performance and exhaust emissions of a single cylinder four stroke naturally aspirated direct injection and air cooled diesel engine. Test results show that the brake thermal efficiency increases with the increase in the percentage of EGr which is accompanied by a reduction in brake specific fuel consumption and exhaust gas temperatures, and that bio- diesel with cetane improver under 20% EGr reduces NOx emissions by 33% when compared to baseline fuel without EGr. However carbon monoxide （CO）, hydro carbon （HC） and smoke emissions increase with an increase in percentage of EGr.

关键词： additive exhaust gas recirculation (EGr),emissions ethyl hexyl nitrate (EHN) performance

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Solar Pv-Battery-Electric Grid-Based Energy System for residential Applications: System Configuration and viability

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research 2019年第1期2019卷 486-502页

作者： v.Bagalini B.Y.Zhao r.Z.Wang u.Desideri university of Pisa DESTEC Largo Lucio LazzarinoPisa 56122Italy Institute of refrigeration and Cryogenics Shanghai Jiao Tong UniversityShanghai 200240China

Distributed renewable energy share increase in electricity generation is creating challenges for the whole power system,due to its intermittent and nonprogrammable *** storage has the potential to solve those issues although its technical,economic,and environmental impact is up for *** paper presents a study about a Pv-battery energy storage system installed in a gridconnected residential apartment in the Green Energy Laboratory at Shanghai Jiao Tong university,*** experimental results show how the presence of energy storage reduces the midday feed-in of excess Pv power and the evening peak demand,providing benefits to the distribution network in terms of reduced voltage swings and peak *** the Chinese context,an economic analysis is carried out to assess the profitability of residential Pv-battery systems,using the net present value as the economic indicator of an 18-year investment in which the battery pack is replaced twice(6 life years).The analysis shows that such system is not economically viable due to a combination of low electricity prices,valuable Pv incentives,and high technology ***,considering a future scenario of doubled electricity tariff,halved export tariff,and falling technology costs(-66%battery and-17%Pv and inverter),Pv-battery investment becomes profitable and shows more resilience to future scenarios than Pv-only investment.

关键词： battery Battery Solar

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Instability of binary nanofluids with magnetic field

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Applied Mathematics and Mechanics(English Edition) 2015年第6期36卷 693-706页

作者： u.GuPTA J.SHArMA v.SHArMA Dr.S.S.Bhatnagar university Institute of Chemical Engineering and Technology Panjab University Energy research Centre Panjab University Department of Mathematics Himachal Pradesh University

The present paper investigates the effects of a vertical magnetic field on the double diffusive nanofluid convection, The effects of the Brownian motion and ther- mophoresis due to the presence of nanoparticles and the effects of the Dufour and Sorer parameters due to the presence of solute are included in the investigated model. The normal mode technique is used to solve the conservation equations. For the analytical study, valid approximations are made in the complex expression for the rayleigh number to get useful and interesting results. The bottom heavy binary nanofluids are more stable than the regular binary fluids, while the top heavy binary nanofluids are less stable than the regular binary fluids. The critical wave number and the critical rayleigh number in- crease whereas the frequency of oscillation （for the bottom heavy configuration） decreases when the Chandrasekhar number increases. The numerical results for the alumina-water nanofiuid are studied by use of the MATHEMATICA software.

关键词： natural convection binary nanofluid Brownian motion thermophoresis,Chandrasekhar number

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Luminescence investigation of Dy2O2S and Dy2O2SO4 obtained by thermal decomposition of sulfate hydrate

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Journal of rare Earths 2016年第8期34卷 814-819页

作者： r.v.rodngues L.Marciniak L.u.Khan J.r.Matos H.F.Brito W.Strek Institute of Chemistry University of Sao Paulo Butanta 748 26077 Sao Paulo Brasil Institute of Low Temperature and Structure research University of Wroctaw Oko1na 250-422 Wroclaw Poland

The yellow emitting dysprosium oxysulfide （Dy2O2S） and dysprosium oxysulfate （Dy202SO4） compounds were prepared from the thermal decomposition of hydrated dysprosium sulphate. The materials were characterized by using thermogravimetry （TG/DTG）, X-ray powder diffraction （XrD）, Fourier transform infrared （FTIr） and raman spectroscopies. The thermal stability temperatures at around 1151 and 1313 K were determined for the Dy202S and Dy202SO4 materials, respectively. The photolumines- cence properties of the dysprosium oxysulfide were investigated, showing narrow emission bands assigned to the 4F9/2----＊6HJ intracon- figurational transitions of the Dy3＋ ion. The yellow emission color of this phosphor suggests that the Dy202S is a promising material for applications in LEDs.

关键词： Dy202S/Dy202SO4 sulfate thermal decomposition luminescence rare earths

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Synthesis and Crystal Structure of Trans-bis(acesulfamato-O)tetraaquazinc(Ⅱ)

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1047-1050页

作者： SAHIN Onur ICBuDAK Hasan B(u|¨)Y(u|¨)KG(u|¨)NG(O|¨)r Orhan Department of Physics Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey Department of Chemistry Faculty of Arts and SciencesOndokuz Mayis UniversitySamsunTurkey

The title compound, trans-bis（acesulfamato-O）tetraaquazinc（Ⅱ）（I, C8H16N2O12S2Zn）, crystallizes in the triclinic system, space group P1 with a = 5.1638（5）, b = 8.5338（9）, c = 9.9583（9）A, α = 74.325（8）, β = 81.112（7）, γ = 75.800（8）°, v= 407.77（7） A3, Z = 1, F（000） = 236, rint = 0.085, T= 296 K, the final r = 0.029 and wr = 0.078 for 1832 observed reflections with I〉 2σ（0. The ZnⅡcentre resides on a centre of symmetry and has a distorted octahedral geometry. The basal plane is defined by two carbonyl O atoms of two monodentate trans-oriented acesulfamato ligands and two trans-aqua ligands. The axial positions in the octahedron are occupied by two trans-aqua ligands. Intermolecular O-H…O hydrogen bonds produce r22（8） and r22（16） rings, which lead to two- dimensional polymeric chains.

关键词： crystal structure zinc(Ⅱ) octahedral complex hydrogen bonds

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Trace and rare-earth element geochemistry: A tool for petrogenetic and geotectonic modeling of ensimatic ortho-amphibolites from Pan-African belt of Obudu Plateau, Southeastern Nigeria

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Chinese Journal Of Geochemistry 2009年第1期28卷 19-27页

作者： ukaegbu v.u. Beka F.T. Department of Geology University of Port Harcourt Port Harcourt Nigeria

A model for the petrogenetic affinity and original geotectonic setting of ortho-amphibolites from the Obudu Plateau was tested using the distribution patterns of trace and rare-earth elements from the geochemical analyses of twelve representative amphibolite samples. Discrimination plots, normalized patterns of the incompatible trace elements against average MOrB, low ratios of Ba/Nb (9–23) and Ba/Ta (130–327) and other geochemical characteristics suggest that the protoliths were dominantly of tholeiitic MOrB composition. The values of the ratios of La/Ta (8.13–10.8), rb/Sr (0.04–0.07), Th/u (mainly 4.43–5.43) and Hf/Ta (2.35–2.88) further indicate that the ortho-amphibolites demonstrate E-type MOrB characteristics. These features are related to substantial ocean floor divergent tectonic boundary setting rather than marginal basin tectonic setting. This evolutionary pattern appears to be controlled by limited progressive partial melting and fractional crystallization of a single mantle source region, irrespective, however, of variations due to local source heterogeneities. The tholeiitic magmas were most probably generated by hotspot activities on the constructive plate margins and subsequently modified by subduction-related low-K tholeiitic chemistry due to narrowing of a proto oceanic basin between the West African craton and eastern Sahara plate. A likely model, therefore, is that the amphibolites of the Obudu Plateau represent ophiolitic suites with characteristics of enriched mid-ocean floor tholeiites, which were deformed and metamorphosed during a reversed plate motion involving subduction and collision within the Obudu Plateau in the Pan-African orogenic episode.

关键词： rEE 微量元素地面沉陷角闪岩地球化学

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Petrology and geochemical characteristics of Precambrian granitic basement complex rocks in the southernmost part of North-Central Nigeria

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Chinese Journal Of Geochemistry 2009年第4期28卷 377-385页

作者： Obiora S.C. ukaegbu v.u. National Geophysical research Institute Geological Studies DivisionUppal Road Hyderabad-500007 India Department of Geology University of NigeriaNsukka Nigeria Department of Geology University of Port HarcourtPort Harcourt Nigeria

The Precambrian basement complex in the southernmost part of North-Central Nigeria is underlain by migmatitic banded gneisses, granitic intrusions and dykes of dolerite, rhyolite porphyry and pegmatite. The rocks are generally felsic, containing modal and normative hypersthene, as well as normative corundum. The basement complex has experienced high-grade regional metamorphism as indicated by the presence of hypersthene and plagioclase of andesine composition. Anatectic melting is suggested by the occurrence of ptygmatic folds, folded gneissose foliation, numerous quartzo-feldspathic veins and lenses of dark-colured, micaceous schistose rocks. Geochemically, the rocks have magnesian, calc-alkalic and strongly peraluminous characteristics. Their overall characteristics suggest derivation from progressive (fractional) partial melting of pelitic rocks during high-grade regional metamorphism, possibly associated with intense hydrothermal activities. The magnesian characteristics reflect close affinity to relatively hydrous, oxidizing melts and source regions in settings broadly related to subduction.

关键词：岩石地球化学特征前寒武纪基底尼日利亚花岗岩中央区域变质作用流纹斑岩叶状结构

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user preference-based intelligent road route recommendation using SArSA and dynamic programming

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Journal of Control and Decision 2023年第3期10卷 443-453页

作者： roopa ravish Shanta rangaswamy Arpitha v vasuprada u PES university BengaluruIndia rashtreeya vidyalaya College of Engineering BengaluruIndia

Traffic congestion is one of the main challenges in transportation engineering. It directly impactsthe economy by increasing travel time and affecting the environment by excessive fuel consumptionand emission. road route recommendation to overcome the congestion by alternativeroute suggestions has gained high importance. The existing route recommendation systems areproposed using the reinforcement learning algorithm (Q-learning). The techniques suggestedin this paper are state-action-reward-state-action (SArSA) algorithm and dynamic programming(DP) to guide the commuters to reach the destination with an optimal solution. The algorithmconsiders travel time, cost, flexibility, and traffic intensity as the user preference attributes torecommend an optimal route. The recommended system is implemented by building a roadnetwork graph. We assign values to each user preference attribute along the edges, which cantake high(1) or low(0) values. By considering these values, the system recommends the *** proposed system performance is evaluated based on computation time, cumulative reward,and accuracy. The results show that DP outperforms the SArSA algorithm.

关键词： Intelligent transport system machine learning techniques in ITS SArSA algorithm dynamic programming route guidance system travel time prediction traveller information system

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