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Fluid Inclusion Studies and Geochemistry of Rare Earth Elements of Hydrothermal Fluorites from Pohrenk,Kirsehir,Central Turkey

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Acta Geologica Sinica(English Edition) 2001年第1期75卷 59-65页

作者： Sükrü KOC Ali RECBER Geology Department Ankara UniversityAnkara 06100Turkey General Directorate of Mineral Research and Exploration Ankara

Fluorite mineralization occurs along fractures and cracks of Middle Eocene and Pliocene limestones and marls in the north and northeast of the P?hrenk region (?i?ekdagi, Kirsehir). Tb/Ca – Tb/La and Y/Ho ratios were obtained from REE contents of fluorites which have revealed that mineralization is of hydrothermal type. Negative Ce anomalies and positive Eu anomalies reflect that hydrothermal solutions once had high oxygen fugacity. Fluid inclusion studies indicate that homogenization temperatures of mineralization varied between 90°C and 200°C, and hydrothermal solutions are composed of NaCl + KCl + MgCl2 + H2O. In addition, salinity measurements show that hydrothermal solutions were mixed with meteoric or rock formation water. Geologic setting, REE geochemistry and fluid inclusion studies suggest that mineralization was deposited from a solution generated by mixing of magmatic and meteoric water under epithermal conditions.

关键词： fluorite rare earth elements fluid inclusions

Chiral Synthesis of the Key Intermediate of Diterpenoids

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Chinese Chemical Letters 1997年第11期8卷 949-950页

作者： Hao, XJ Node, MB Fuji, kr Chinese Acad Sci Kunming Inst Bot Kunming 650204 Peoples R China Kyoto Pharmaceut Univ Yamashima Ku Kyoto 607 Japan Kyoto Univ Inst Chem Res Uji 611 Japan

(-)-Methyl(4R, 5S, 10R)-14-methoxypodocarpa-8, 11, 13-triene-19-oate(1), which is the key intermediate for synthesis of diterpenoids, was synthesized from (R)-(+)-2-methyl-2-(2`-nitrovinyl)-delta-valerolactone(2).

关键词： ADDITION ELIMINATION PROCESS NITROOLEFINATION LACTONES

NODAL O(h^4)-SUPERCONVERGENCE IN 3D BY AVERAGING PIECEWISE LINEAR,BILINEAR,AND TRILINEAR FE APPROXIMATIONS

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Journal of Computational Mathematics 2010年第1期28卷 1-10页

作者： Antti Hannukainen Sergey Korotov Michal krízek Institute of Mathematics Helsinki University of Technology Department of Mathematics Tampere University of Technology Institute of Mathematics Academy of Sciences

We construct and analyse a nodal O（h^4）-superconvergent FE scheme for approximating the Poisson equation with homogeneous boundary conditions in three-dimensional domains by means of piecewise trilinear functions. The scheme is based on averaging the equations that arise from FE approximations on uniform cubic, tetrahedral, and prismatic partitions. This approach presents a three-dimensional generalization of a two-dimensional averaging of linear and bilinear elements which also exhibits nodal O（h^4）-superconvergence （ultracon- vergence）. The obtained superconvergence result is illustrated by two numerical examples.

关键词： Higher order error estimates Tetrahedral and prismatic elements Supercon-vergence Averaging operators.

Geochemistry of Kestelek Colemanite Deposit, Bursa, Turkey

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Journal of Earth Science 2017年第1期28卷 63-77页

作者： sükrü Koc Ozge Kavrazh ismail Kocak Faculty of Department of Geological Engineering Ankara University Ankara 06100 Turkey Graduate School of Natural and Applied Sciences Ankara University Ankara 06100 Turkey Department of Geological Engineering Bozok University Yozgat 66100 Turkey

The Kestelek borate deposit has been the subject of geological and mineralogical research over the last decades, but major and trace element geochemistry of this deposit was first investigated in the present study. A total of 22 samples collected from surface exposures and different depths of deposit in boreholes（e.g., lower, middle and upper） comprise the material of this study. Major, trace and REE element analyses of samples were conducted with ICP-MS and ICP-ES methods. The Kestelek borate deposit of Miocene age was formed in playa lakes in an intermountain closed basin which was developed in volcanically and seismically active areas associated with growth faults and grabens affected the whole Anatolia at the beginning of Paleogene. Only colemanite was found as the borate mineral accompanied in lesser amount by calcite, aragonite, smectite, illite, chlorite, corrensite, heulandite and quartz. In colemanite samples, all major elements, except for Ca, show depletion trends with respect to average of earth crust and andesite. For the trace elements, Li, Cs, Sb, As, Sr and Se are characterized by significantly high concentrations. Evaluation of element concentrations and geochemical characteristics reveal that As, Cs, Sb and Li are of detrital origin, Se together with B and Ca are of non-detrital and Sr is indicative of both detrital and non-detrital origin. REE distributions indicate that at least two different depositional regimes prevail in the environment. Corrensite, a clay mineral forming in lake waters, is derived from volcanism. Negative Ce and positive Eu anomalies are indicative of contribution from hydrothermal solutions and fluids.

关键词： borate mineralogy geochemistry REE Kestelek Turkey.

Influence of heat treatment on the structural and optical properties of SrGd_2O_4:Eu^(3+) phosphor

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Journal of Rare Earths 2015年第10期33卷 1040-1050页

作者： Jyoti Singh Pankaj kr.Baitha J.Manam Department of Applied Physics Indian School of Mines

Novel red emitting Eu3＋ doped SrGd2O4 phosphors were synthesized by homogeneous precipitation method followed by a subsequent combustion process at various temperatures. A systematic study on the consequent structural evolution and optical properties were investigated as a function of various processing temperatures. With the enhancement of processing temperature, SrGd2O4 phosphor showed a gradual transformation from a mixed phase to monophasic nature, with minimized volatile imptwities. The microscopic images exhibited homogeneous aggregates of varying shapes and sizes with an average length of about 0.5-5μl. Eu3＋ doped SrGd2O4 phosphors prepared at low temperatures, showed miserably low values of red emission upon UV excitation owing to the presence of volatile impurities. The SrGd2O4：Eu3＋ phosphors prepared at relatively high temperature exhibited strong red-orange emissions due to homogeneously occupied Eu3＋ ions in the host lattice. The dominant red to orange （R/O） emission intensity ratios and CIE parameters of EU3＋ ions substantiated the site occupation of higher asymmetry sites of Gd3＋ ions and the strong covalent nature. Dexter theory and critical distance calculation suggested that the dipole-dipole interaction could be responsible for the concentration quenching of Eu3＋（4 mol.%） doped SrGd2O4 phosphors. Elevated physical and chemical durability and stable photoluminescence made these phosphors suitable for white LEDs and other display applications.

关键词： optical materials chemical synthesis X-ray diffraction luminescence rare earths

Changes in carbon stocks of soil and forest floor in black pine plantations in Turkey

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Journal of Forestry Research 2021年第1期32卷 339-347页

作者： SükrüTeoman Güner Dilek Güner General Directorate of Forestry Research Institute for Forest Soil and Ecology26160 EskisehirTurkey

The objectives of this study were:(1)to determine carbon stock changes in the soil and forest floor of black pine(Pinus nigra ***)plantations in Turkey;(2)to determine the effects of thinning on annual carbon accumulation in both;and,(3)to investigate relationships between annual carbon storage in soil and forest floor and stand characteristics of black *** were taken in 90 plots from stands at the pole(dbh=11.0–19.9 cm)and sawlog(dbh=20.0–35.9 cm)*** analyses of soil and forest floor samples showed that in unthinned plantations signifi cant organic carbon was sequestered an average of 1.47 Mg ha^−1 a^−1 in the soil and 0.20 Mg ha^−1 a^−1 in the forest *** carbon sequestered annually in the soil was signifi cantly lower in thinned than in unthinned stands,while diff erences in the forest floor were insignifi *** were positive correlations between carbon sequestered in the soil and stand age,average DBH,mean stand height,basal area,and site *** sequestered the forest floor increased with basal *** a result,carbon sequestered in the soil should not be ignored in greenhouse gas inventories because carbon stored belowground was approximately 70%of the aboveground pool.

关键词： Pinus nigra Belowground Forest floor Carbon sequestration Thinning

Transjugular intrahepatic portosystemic shunt vs conservative treatment for recurrent ascites:A propensity score matched comparison

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World Journal of Gastroenterology 2022年第41期28卷 5944-5956页

作者： Martin Philipp Theresia Blattmann Jörn Bienert kristian Fischer Luisa Hausberg Jens-Christian kröger Thomas Heller Marc-AndréWeber Georg Lamprecht Department of Medicine Division of Gastroenterology and EndocrinologyRostock University Medical CenterRostock 18057Germany Institute of Diagnostic and Interventional Radiology Pediatric Radiology and NeuroradiologyRostock University Medical CentreRostock 18057Germany

BACKGROUND Transjugular intrahepatic portosystemic shunt(TIPS) placement is an effective intervention for recurrent tense ascites. Some studies show an increased risk of acute on chronic liver failure(ACLF) associated with TIPS placement. It is not clear whether ACLF in this context is a consequence of TIPS or of the pre-existing liver *** To better understand the risks of TIPS in this challenging setting and to compare them with those of conservative *** Two hundred and fourteen patients undergoing their first TIPS placement for recurrent tense ascites at our tertiary-care center between 2007 and 2017 were identified(TIPS group). Three hundred and ninety-eight patients of the same time interval with liver cirrhosis and recurrent tense ascites not undergoing TIPS placement(No TIPS group) were analyzed as a control group. TIPS indication,diagnosis of recurrent ascites, further diagnoses and clinical findings were obtained from a database search and patient records. The in-hospital mortality and ACLF incidence of both groups were compared using 1:1 propensity score matching and multivariate logistic *** After propensity score matching, the TIPS and No TIPS groups were comparable in terms of laboratory values and ACLF incidence at hospital admission. There was no detectable difference in mortality(TIPS: 11/214, No TIPS 13/214). During the hospital stay, ACLF occurred more frequently in the TIPS group than in the No TIPS group(TIPS: 70/214, No TIPS: 57/214, P = 0.04). This effect was confined to patients with severely impaired liver function at hospital admission as indicated by a significant interaction term of Child score and TIPS placement in multivariate logistic regression. The TIPS group had a lower ACLF incidence at Child scores < 8 points and a higher ACLF incidence at ≥ 11 points. No significant difference was found between groups in patients with Child scores of 8 to 10 *** TIPS placement for recurrent tense as

关键词： Liver cirrhosis Ascites Transjugular intrahepatic portosystemic shunt Acute on chronic liver failure Mortality Propensity score

Content of blood cell components,inflammatory cytokines and growth factors in autologous platelet-rich plasma obtained by various methods

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World Journal of Orthopedics 2022年第6期13卷 587-602页

作者： Maciej Dejnek Jarosław Witkowski Helena Moreira Sylwia Płaczkowska Piotr Morasiewicz PawełReichert Aleksandra.królikowska Department of Trauma Surgery Wroclaw Medical UniversityWroclaw 50-556Poland Department of Medical Science Foundation Wroclaw Medical UniversityWroclaw 50-556Poland Teaching and Research Diagnostic Laboratory Department of Laboratory DiagnosticsWroclaw Medical UniversityWroclaw 50-556Poland Institute of Medical Sciences Department of Orthopaedic and Trauma SurgeryUniversity of OpoleOpole 45-052Poland Ergonomics and Biomedical Monitoring Laboratory Department of PhysiotherapyWroclaw Medical UniversityWroclaw 50-355Poland

BACKGROUND The evaluation of the efficacy of platelet-rich plasma(PRP) in clinical practice yields conflicting results and raises numerous controversies. This may be due to different concentrations of biologically active components in PRP obtained with the use of different methods of gravity *** To compare the content, repeatability and correlations between biologically active components in PRP obtained with four different commercial *** From a whole blood sample of each of 12 healthy male volunteers, 4 PRP samples were prepared using 4 different commercial kits [Arthrex Autologous Conditioned Plasma(ACP), Mini GPS Ⅲ, Xerthra, Dr. PRP] in accordance with the instructions provided by the manufacturers. A comparative analysis of blood cell components-13 selected inflammatory cytokines and 7 growth factors-in the obtained PRP samples was performed using the kruskal-Wallis test by ranks. The repeatability of results in each method was evaluated by the estimation of the coefficient of variation. The Spearman correlation was used to estimate the relationship between blood cell content and *** Significantly higher concentrations of platelets(PLT), white blood cells(WBC) and red blood cells(RBC) were found in PRP obtained with the use of Mini GPS Ⅲ than in PRP obtained using other systems. Significant differences in the content of growth factors and cytokines in PRP were found. A positive correlation of the amount of PLT, RBC and WBC with the concentration of most of the growth factors was found but in only three inflammatory cytokines. The obtained correlations between blood cell components and cytokines differed between the systems in terms of statistical significance, which may be due to insufficient sample size. The repeatability of the obtained PLT concentration also varied between protocols with the lowest in Xerthra and the highest in Arthrex *** Significant differences in the content of biologically active components a

关键词： Platelet-rich plasma Cytokines Chemokines Growth factors

A Review on Pharmacological Significance of Genus Jatropha(Euphorbiaceae)

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Chinese Journal of Integrative Medicine 2012年第11期18卷 868-880页

作者： Surendra.kr.Sharma Harneet Singh Medicine Press and Springer-Verlag Berlin Heidelberg 2012 Guru Jambheshwar University of Science and Technology-Pharmaceutical Sciences

A number of herbs belonging to the genus Jatropha of Euphorbiaceae family are noted for their medicinal benefits. The genus Jatropha is one of the prospective biodiesel yielding crops. The plants which have been so far explored include J. curcas, J. gossypifolia, J. glandu/ifera, J. multifida and J. podagrica. Although, the plants of this genus are widely distributed, there is an exiguity of scientific literature proclaiming the medicinal benefits of the plants belonging to genus Jatropha. The present paper is a pragmatic approach to accrue the findings on this very significant genus.

关键词： Jatropha Euphorbiaceae pharmacological activity