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Spectroscopic investigations on the effect of humic acid on the formation and solubility of secondary solid phases of Ln_2(CO_3)_3

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Journal of Rare Earths 2011年第6期29卷 516-521页

作者： Stella Antoniou ioannis Pashalidis Andre Gessner Michael u Kumke Department of Chemistry University of Cyprus P.O. Box 20537 1678 Nicosia Cyprus Chemistry Department/Physical Chemistry University of Potsdam Karl- Liebknecht-Str. 24-25 14476 Potsdam-Golm Germany

The formation of secondary Ln（III） solid phases （e.g., Nd2（CO3）3 and Sm2（CO3）3） was studied as a function of the humic acid concentration in 0.1 mol/L NaClO4 aqueous solution in the neutral pH range （5–6.5）. The solid phases under investigation were prepared by alkaline precipitation under 100% CO2 atmosphere and characterized by attenuated total reflectance Fourier transform infrared spectroscopy （ATR-FTIR）, X-ray diffraction （XRD）, time-resolved laser fluorescence spectroscopy （TRLFS）, diffuse reflectance ultraviolet-visible （DR-uV-Vis）, Raman spectroscopy, and solubility measurements. The spectroscopic data obtained indicated that Nd2（CO3）3 and Sm2（CO3）3 were stable and remained the solubility limiting solid phases even in the presence of increased humic acid concentration （0.5 g/L） in solution. upon base addition in the Ln（III）-HA system, decomplexation of the previously formed Ln（III）-humate complexes and precipitation of two distinct phases occurred, the inorganic （Ln2（CO3）3） and the organic phase （HA）, which was adsorbed on the particle surface of the former. Nevertheless, humic acid affected the particle size of the solid phases. Increasing humic acid concentration resulted in decreasing crystallite size of the Nd2（CO3）3 and increasing crystallite size of the Sm2（CO3）3 solid phase, and affected inversely the solubility of the solid phases. However, this impact on the solid phase properties was expected to be of minor relevance regarding the chemical behavior and migration of trivalent lanthanides and actinides in the geosphere.

关键词： lanthanide ions humic acid solid phase solubility Raman TRLFS DR-uV-Vis rare earths

Complexity of the NWA 773 Clan: New Evidence from Lunar Olivine Gabbro NWA 6950

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Journal of Earth Science 2023年

作者： Qi He Long Xiao ioannis Baziotis Xiaochao Che Yuqi Qian Jiawei Zhao Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Planetary Science Institute School of Earth Sciences China university of Geosciences 2. Laboratory of Mineralogy and Geology Agricultural university of Athens

NWA 6950 is a type of cumulate gabbro meteorite that displays features indicating a lunar origin. Specifically， the Fe/Mn values of olivines and pyroxenes in the meteorite suggest a lunar origin， as does the presence of Fe-Ni metal. The meteorite has also undergone intense shock metamorphism， which is evidenced by the presence of ringwoodite， tuite， and xieite (a type of chromite with a CaTi2O4structure) within the shock melt veins (SMVs).The texture， mineral modal abundances， and bulk compositions (measured from the SMVs) of NWA 6950 are similar to those of the NWA 773 clan， as are the concentrations and patterns of rare-earth-elements in olivine， pyroxene， plagioclase， and phosphate. In-situ u-Pb dating of baddeleyite and phosphate in NWA 6950 has determined its crystallization age to be 3 133 ± 11 Ma and 3 129 ± 23 Ma， which is consistent with age data provided by Shaulis et al. (2017).Further， the chronology of the NWA 773 clan appears to be at least bimodal when considering the age of NWA 3333 (3 038 ± 20 Ma; Merle et al.， 2020). The tight range of ages for the NWA 773 clan at approximately 3.1 Ga coincides with a change in the eruption flux and style on the Moon. This suggests that lunar volcanism may have shifted from extrusive-dominated to intrusive-dominated at approximately 3.1 Ga， resulting in the widespread distribution of gabbro lithologies on the Moon.

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Tangential Developable Surfaces as Bonnet Surfaces

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Acta Mathematica Sinica,English Series 1999年第2期15卷 269-276页

作者： ioannis M. Roussos, Department of Mathematics, Hamline university, Saint Paul, MN 55104-1284, u. S. AE-mail: iroussos@seq.hamline, edu Department of Mathematics Hamline University Saint Paul U. S. A.

We study the real Bonnet surfaces which accept one unique nontrivial isometry that preserves the mean curvature, in the three-dimensional Euclidean space. We give a general criterion for these surfaces and use it to determine the tangential developable surfaces of this kind. They are determined implicitly by elliptic integrals of the third kind. Only the tangential developable surfaces of circular helices are explicit examples for which we completely determine the above unique nontrivial isometry.

关键词： Bonnet surface Mean curvature Isometry Tangential developable Elliptic integral Circular helix

Current update on nanoplatforms as therapeutic and diagnostic tools:A review for the materials used as nanotheranostics and imaging modalities

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Asian Journal of Pharmaceutical Sciences 2021年第1期16卷 24-46页

作者： Panoraia I.Siafaka Neslihan ustundag Okur ioannis D.Karantas Mehmet Evren Okur Evren Atlihan Gundogdu Department of Chemistry Aristotle University of ThessalonikiThessalonikiGreece Faculty of Pharmacy Department of Pharmaceutical TechnologyUniversity of Health SciencesIstanbulTurkey 2nd Clinic of Internal Medicine Hippokration General HospitalThessalonikiGreece Faculty of Pharmacy Department of PharmacologyUniversity of Health SciencesIstanbulTurkey Faculty of Pharmacy Department of RadiopharmacyEge UniversityIzmir 35100Turkey

In the last decade,the use of nanotheranostics as emerging diagnostic and therapeutic tools for various diseases,especially cancer,is held great *** to date,several approaches have been employed in order to develop smart nanotheranostics,which combine bioactive targeting on specific tissues as well as diagnostic *** nanotheranostics can deliver therapeutic agents by concomitantly monitor the therapy response in ***,the possibility of over-or under-dosing is *** non-invasive imaging techniques have been used to quantitatively monitor the drug delivery *** of nanomaterials is widely used as powerful diagnostic approach on nuclear medicine *** fact,various radiolabeled nanomaterials have been designed and developed for imaging tumors and other lesions due to their efficient *** nanoparticles as gold,silver,silica based nanomaterials or organic nanoparticles as polymers,carbon based nanomaterials,liposomes have been reported asmultifunctional *** this review,the imaging modalities according to their use in various diseases are summarized,providing special details for *** further,the most current nanotheranostics categorized via the used nanomaterials are also summed *** conclude,this review can be beneficial for medical and pharmaceutical society as well as material scientists who work in the field of nanotheranostics since they can use this research as guide for producing newer and more efficient nanotheranostics.

关键词： Theranostics Nanomedicine Nanotechnology Nanoparticles Radiopharmaceuticals

Flaring activity from quiescent states in neutron-star X-ray binaries

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Research in Astronomy and Astrophysics 2018年第11期18卷 123-132页

作者： Dimitris M.Christodoulou Silas G.T.Laycock Demosthenes Kazanas ioannis Contopoulos Lowell Center for Space Science and Technology University of Massachusetts LowellLowellMA01854USA Dept.of Mathematical Sciences Univ.of Massachusetts LowellLowellMA01854USA Dept.of Physics&Applied Physics Univ.of Massachusetts LowellLowellMA01854USA NASA/GSFC Laboratory for High-Energy AstrophysicsCode 663GreenbeltMD20771USA Research Center for Astronomy and Applied Mathematics Academy of AthensAthens 11527Greece NationalResearch Nuclear university Moscow 115409Russia

We examine systematically the observed X-ray luminosity jumps(or flares) from quiescent states in millisecond binary pulsars(MSBPs) and high-mass X-ray binary pulsars(HMXBPs). We rely on the published X-ray light curves of seven pulsars: four HMXBPs, two MSBPs and the ultraluminous X-ray pulsar M82 X-2. We discuss the physics of their flaring activities or lack thereof, paying special attention to their emission properties when they are found on the propeller line, inside the Corbet gap or near the light-cylinder barrier. We provide guiding principles for future interpretations of faint X-ray observations, as well as a method of constraining the propeller lines and the dipolar surface magnetic fields of pulsars using a variety of quiescent states. In the process, we clarify some disturbing inaccuracies that have made their way into the published literature.

关键词： accretion accretion disks pulsars: individual(4u 0115+63,V 0332+53,M82 X-2,Aquila X-1,SAX J1808.4–3658,AX J0049.4–7323,1A 0535+262) stars: magnetic fields stars: neutron X-rays: binariesà?G

与 transarterial chemoembolization 对待的 Hepatocellular 癌: 有参量的提高对比的 ultrasonography 的评估

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World Journal of Radiology 2012年第8期4卷 379-386页

作者： Hippocrates Moschouris Katerina Malagari Athanasios Marinis ioannis Kornezos Konstantinos Stamatiou Georgios Nikas Marina Georgiou Papadaki Panagiotis Gkoutzios Department of Radiology Tzaneion General Hospital18536 PiraeusGreece Second Department of Radiology University of AthensAttikon HospitalChaidari12462 AthensGreece First Department of General Surgery Tzaneion General Hospital18536 PiraeusGreece Department of urology General Hospital 'Tzanio'18536 PiraeusGreece Department of Interventional Radiology Guy’s and St.Thomas’ HospitalNHS Foundation TrustSE17EH LondonUnited Kingdom

AIM:To evaluate the response of hepatocellular carcinoma(HCC) to transarterial chemoembolization(TACE) using a simplified protocol of parametric contrastenhanced ultrasound(pCEuS).METHODS:Eighteen patients with HCC(18 target tumors,diameter:2.8-12 cm) were evaluated before,and 20 d after *** distribution and morphology of TACE-induced necrosis in these tumors precluded accurate evaluation by visual assessment or by simple *** pCEuS,a 4.8 mL bolus of SonoVue(Bracco,Milan,Italy) was intravenously administered and analysis of tumor perfusion during the initial phase of enhancement(0-30 s post injection) was performed with dedicated software(Qontrast,Bracco,Milan,Italy).Time-intensity curves were plotted and three parameters were calculated:peak intensity(PI,in percentage %),time to peak(TTP in seconds,s) and area under the curve during wash-in(AuC-WI,in arbitrary units,a.u).Magnetic resonance imaging was the standard imaging modality for post-treatment *** in tumor size were recorded and response was assessed according to response evaluation criteria in solid tumors ***:A statistically significant decrease in PI and AuC-WI was observed in the treated tumors post TACE;PIpre:21.5% ± 8.7%(mean ± SD),PIpost:12.7% ± 6.7%,P uC-WI pre:17493 ± 9563 a.u,AuCWI post:9585 ± 5494 a.u,P ut this was not statistically significant;TTP pre:13.1 ± 4.3 s,TTP post:13.6 ± 4.2 s,P = 0.058).The changes in the aforementioned parameters were not accompanied by significant tumor ***:pCEuS,even when limited to the study of the arterial phase of tumoral enhancement,can detect and quantify early perfusional changes in HCC post TACE.

关键词： Contrast-enhanced ultrasonography Hepatocellular carcinoma Parametric imaging Transarterial chemoembolization