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Dipole and generalized oscillator strength derived electronic properties of an endohedral hydrogen atom embedded in a Debye-Huckel plasma

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Matter and Radiation at Extremes 2018年第5期3卷 227-242页

作者： c.Martínez-Flores R.cabrera-Trujillo Instituto de ciencias Físicas Universidad Nacional Autonoma de MexicoAp.Postal 43-8CuernavacaMorelos62251Mexico

we report electronic properties of a hydrogen atom encaged by an endohedral cavity under the influence of a weak plasma interaction. weimplement a finite-difference approach to solve the Schrodinger equation for a hydrogen atom embedded in an endohedral cavity modeled by thewoods-Saxon potential with well depth V0, inner radius R0, thickness D, and smooth parameter g. The plasma interaction is described by aDebye-Hu¨ckel screening potential that characterizes the plasma in terms of a Debye screening length lD. The electronic properties of theendohedral hydrogen atom are reported for selected endohedral cavity well depths, V0, and screening lengths, lD, that emulate differentconfinement and plasma conditions. we find that for low screening lengths, the endohedral cavity potential dominates over the plasma interaction by confining the electron within the cavity. For large screening lengths, a competition between both interactions is observed. we assessand report the photo-ionization cross section, dipole polarizability, mean excitation energy, and electronic stopping cross section as function of lD and V0. we find a decrease of the Generalized Oscillator Strength (GOS) when the final excitation is to an s state as the plasma screeninglength decreases. For a final excitation into a p state, we find an increase in the GOS as the endohedral cavity well-depth increases. For the caseof the electronic stopping cross section, we find that the plasma screening and endohedral cavity effects are larger in the low-to-intermediateprojectile energies for all potential well depths considered. Our results agree well to available theoretical and experimental data and are afirst step towards the understanding of dipole and generalized oscillator strength dependent properties of an atom in extreme conditions encagedby an endohedral cavity immersed in a plasma medium.

关键词： Oscillator strengths Debye-Huckel plasma cavities Endohedral Energy loss Stopping power

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A Novel Sample Introduction Technique for the Simultaneous Determination of As,Se,Ge and Hg in chinese Medicinal Material

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chemical Research in chinese Universities 2001年第4期17卷 400-406页

作者： chen Bin Zhuang Zhixia wang Xiaoru FRANKs.c.lee 厦门大学教育部现代分析科学重点实验室福建厦门 361005 香港浸会大学香港

A novel technique of Moveable Reduction Bed Hydride Generator（MRBHG）was applied tohe hydride generation or cold vapor generation of As，Se，Ge，and Hg existing In Traditionalchinese Medicinal Material（TcM）．The simultaneous determination of the multi－elements wasperformed with IcP－MS．A solid reduction system involving the use of potassiumtetraborohydride and tartaric acid was applied to generating metal hydride or cold *** factors affecting the metal cold vapor generation were *** mainadvantage of the technique is that only a 4μL volume of sample was required for the cold vapor

关键词： for the Simultaneous Determination of As,Se,Ge A Novel Sample Introduction Technique chinese Material Medicinal and Hg Ge

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Low symmetry aspects in spectroscopic and magnetic susceptibility studies of Tb^(3+)(4f^8) in TbAlO_3

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Journal of Rare Earths 2009年第4期27卷 627-632页

作者： c.Rudowicz P.Gnutek M.G.Brik Modeling in Spectroscopy Group Institute of Physics West Pomeranian University of Technology Institute of Physics University of Tartu

The three sets of crystal field parameters （cFPs） obtained from spectroscopic and magnetic susceptibility studies of Tb3＋（4f^8） ions in TbAlO3 by Gruber et al. （J. Lumin. 128 （2008） 1271） were reanalyzed. These sets, fitted from experimental energy levels, are physically equivalent and correspond to specific choices of the axis system. Proper interpretation of experimental data for Tb3＋ ions at monoclinic c8 symmetry sites in TbAlO3 crystal requires clarification of several intricate low syrmnetry aspects, namely, （a） three equivalent forms of monoclinic cF Hamiltouian, （b） relative orientation of the crystallographic axis system w.r.t, the symmetry-adapted axis system, （c） monoclinic standardization of cFPs, （d） distinction between the actual and apparent low symmetry effects exhibited by cFPs, and （e） nominal nature of all fitted cFP sets. For this purpose, modeling of cFPs for Tb3＋ in TbAlO3 was carried out using at the first stage only the coulomb, i.e. point charge, eonlribntions in the exchange charge model. The point charge model calculated cFPs disagree with the experimental cFPs, especially the rank k=6 cFPs. To explain this discrepancy and to verify the correcmess of the theoretical cFP calculations additionally the superposition model was employed. The methods of analysis and modeling of cFP sets for monoclinic symmetry cases proposed here proved useful for the studied case as well as might be used for other ion-host systems exhibiting monoclinic or triclinic local site symmetry. Partial results for Tb3＋ ions in TbAlO3 were presented here, whereas detailed results were given in a follow-up paper.

关键词： Tb3+ ions TbAlO3 spectroscopy crystal-field magnetic susceptibility low symmetry aspects rare earths

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cretaceous Oceanic Red Beds （cORB）, response to paleoclimatic/paleoceanographic global changes and regional tectonics workshop of IGcP 463 ＆ 494

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Episodes 2006年第1期29卷 49-51页

作者： Robert w. Scott chengshan wang Xiumian Hu Tulsa University cleveland Oklahoma 74020 USA china University of Geosciences Beijing 100083 Beijing CHINA Nanjing University210093 Nanjing cHINA

Members of IGcP 463, cretaceous Oceanic Red Beds （cORBs）, held their fourth workshop in Switzerland, and members of IGcP Project 494, Dysoxic to oxic change in midcretaceous Tethyan oceanic sedimentation, held their third workshop. The joint workshops consisted of a day and a half of presentations of current scientific results and a halfday planning the next year＇s work flow. Afterwards many participants joined the oneday field trip ＂Aptian, Albian, and cenomanian sedimentation in the Swiss Prealps＂ led by Michel caron, Luc Braillard, Andre Strasser, and corinne Saudan, which preceded the 7th International Symposium on the cretaceous, 5-9 September, 2005. Projects 463 ＆ 494 also sponsored oral and poster sessions at the Symposium entitled, ＂cretaceous Oceanic Red Beds＂.

关键词：区域构造学全球变化海洋层白垩纪

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Hepatocellular carcinoma in African Blacks: Recent progress in etiology and pathogenesis

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world Journal of Hepatology 2010年第2期2卷 65-73页

作者： Michael c Kew Department of Medicine Groote Schuur HospitalOld Main BuildingK FloorMain RoadObservatory 7935Cape TownSouth Africa

Occult hepatitis B virus (HBV) infection was shown to be present in 75% of Black Africans with hepatocellular carcinoma (Hcc) in whom the tumor was hitherto not thought to be caused by chronic HBV infection. The association between chronic HBV infection and the development of the tumor is thus even closer than was originally thought. HBV viral load was found to be significantly higher in patients with Hcc than in Black African controls. As in other populations, HBV e antigen-positive patients with hepatocellular carcinoma had significantly higher viral loads than patients negative for this antigen. The significance of this finding is discussed. The risk for Hcc development with genotype A of HBV, the predominant genotype in African isolates, has not been investigated. Genotype A was shown to be 4.5 times more likely than other genotypes to cause Hcc in Black Africans, and tumours occurred at a significantly younger age. Increasing numbers of patients with human immunodeficiency virus (HIV) and HBV co-infection are being reported to develop Hcc. A preliminary case/control comparison supports the belief that HIV co-infection enhances the hepatocarcinogenic potential of HBV. A study from The Gambia provides the first evidence that dietary exposure to afltoxin B1 may cause cirrhosis and thatthis may play a contributory role in the pathogenesis of aflatoxin-induced Hcc. An animal model has provided experimental support for the clinical evidence that dietary iron overload in the African is directly hepatocarcinogenic, in addition to causing the tumor indirectly through the development of cirrhosis.

关键词： Hepatocellular carcinoma Black Africans Occult hepatitis B Virus infection Hepatitis B viral loads Hepatitis B virus genotype A Aflatoxin Dietary iron overload

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Absence of complementary sex determination in two Leptopilina species(Figitidae,Hymenoptera)and a reconsideration of its incompatibility with endosymbiont-induced thelytoky

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Insect Science 2022年第3期29卷 900-914页

作者： Fangying chen Martijn Schenkel Elzemiek Geuverink Louis van de Zande Leo w.Beukeboom Groningen Institute for Evolutionary Life Sciences University of GroningenP.O.Box 11103 Groningen9700 CCthe Netherlands

complementary sex determination(cSD)is a widespread sex determination mechanism in haplodiploid *** cSD,sex is determined by the allelic state of one or multiple cSD *** at one or more loci leads to female development,whereas hemizygosity of haploid eggs and homozygosity of diploid eggs results in male ***(arrhenotokous)reproduction normally yields haploid male and diploid female *** asexual reproduction(thelytoky),diploidized unfertilized eggs develop into *** is often induced by bacterial endosymbionts that achieve egg diploidization by gamete *** gamete duplication leads to complete homozygosity,endosymbiont-induced thelytokous reproduction is presumed to be incompatible with cSD,which relies on heterozygosity for female ***,we excluded cSD in four Asobara(Braconidae)species and proposed a two-step mechanism for wolbachia-induced thelytoky in Asobara ***,we conclusively reject cSD in two cynipid wasp species,Leptopilina heterotoma and Leptopilina *** further show that thelytoky in *** depends on wolbachia titer but that diploidization and feminization steps cannot be separated,unlike in *** discuss what these results reveal about the sex determination mechanism of *** and the presumed incompatibility between cSD and endosymbiont-induced thelytoky in the Hymenoptera.

关键词： arrhenotoky haplodiploidy inbreeding sex determination thelytoky wolbachia bacteria

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Assessment of porous aquifer hydrogeological parameters using automated groundwater level measurements in Greece

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Journal of Groundwater Science and Engineering 2021年第4期9卷 269-278页

作者： Marios c Kirlas School of Agriculture Faculty of AgricultureForestry and Natural EnvironmentAristotle University of ThessalonikiUniversity campusThessaloniki 54124Greece.

In this paper,the hydrogeological parameters of a confined aquifer,such as transmissivity(T),storativity(S)and radius of influence(R),have been assessed using real groundwater level measurements recorded by a monitoring network,consisting of automated municipal water supply boreholes at Nea Moudania aquifer,chalkidiki,***,the paper focused on the correlation between the drawdown and the constant flow rate during pumping *** the cooper-Jacob and the recovery test method were applied in order to delineate if turbulent head losses occur,as well as the impact of incorrect measurements of the radial distance(r)in the accuracy of estimating S *** results show that a)the occurrence of a linear correlation between s and Q indicates a negligible turbulent head loss in the pumping wells and thus a reasonable flow rate usage,b)the validity of storativity values could be compromised if the r value is not accurately measured,and c)recovery test method can be used as an indicator of residual drawdown(s’)caused by previous pumping cycles,when the straight line intersecting the logarithmic t/t’axis has a value greater than 1.

关键词： cooper-Jacob method Greece Recovery test method Storativity Transmissivity

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coexistence and fluctuations phenomena with Davidson-like potentials in quadrupoleoctupole deformed nuclei

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communications in Theoretical Physics 2021年第3期73卷 105-118页

作者： M M Hammad w H Mansour E M El-Maghraby H A Motaweh Ayman A Aly Faculty of Science Mathematics DepartmentDamanhour UniversityEgypt Faculty of Science Physics DepartmentDamanhour UniversityEgypt

The energy spectra of three types of two-dimensional potentials(we will call them‘Davidson-like potentials’(DLPs)),characterized by four minima separated by barriers,are *** predictions for spectra and wave functions are obtained by using the nine-point finite-difference *** these potentials,with the existence of a single configuration,a transition of spectra,as a function of barrier height,is covered from tunneling splitting modes to fluctuations phenomena,with equal peaks wave functions,crossing to the spectra of purely anharmonic oscillator potentials(AOPs).A different type of phase transition occurs when two(or more)configurations *** the change of the parameters,a transition of spectra is covered from coexistence phenomena of two distinct quantum tunneling modes to fluctuations phenomena,with unequal peaks wave functions,crossing to the spectra of purely *** DLPs,a particular application of the coherent quadropole-octupole model to describe energy bands with alternating parity of the nuclei^(100)Mo,^(146,148)Nd,^(148,150)Sm,^(220)Ra,^(220,222)Rn,and^(220,222)Th is *** global parametrization of the model for the selected nuclei is achieved.

关键词： quantum phase transitions fluctuations phenomena coherent quadrupole-octupole motion model coexistence phenomena

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Effects of intermittent fasting on health markers in those with type 2 diabetes:A pilot study

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world Journal of Diabetes 2017年第4期8卷 154-164页

作者： Terra G Arnason Matthew w Bowen Kerry D Mansell Department of Medicine College of MedicineUniversity of Saskatchewan Division of Pharmacy college of Pharmacy and Nutrition University of Saskatchewan

AIMTo determine the short-term biochemical effects and clinical tolerability of intermittent fasting (IF) in adults with type 2 diabetes mellitus (T2DM).METHODSwe describe a three-phase observational study (baseline 2 wk, intervention 2 wk, follow-up 2 wk) designed to determine the clinical, biochemical, and tolerability of IF in community-dwelling volunteer adults with T2DM. Biochemical, anthropometric, and physical activity measurements (using the Yale Physical Activity Survey) were taken at the end of each phase. Participants reported morning, afternoon and evening self-monitored blood glucose (SMBG) and fasting duration on a daily basis throughout all study stages, in addition to completing a remote food photography diary three times within each study phase. Fasting blood samples were collected on the final days of each study *** baseline, the ten participants had a confirmed diagnosis of T2DM and were all taking metformin, and on average were obese [mean body mass index (BMI) 36.90 kg/m2]. we report here that a short-term period of IF in a small group of individuals with T2DM led to significant group decreases in weight (-1.395 kg, P = 0.009), BMI (-0.517, P = 0.013), and at-target morning glucose (SMBG). Although not a study requirement, all participants preferentially chose eating hours starting in the midafternoon. There was a significant increase (P w attained the 18-20 h fasting goal (mean 16.82 ± 1.18). The increased fasting duration improved at-goal (c Regression models revealed a positive relationship between the increase in hours fasted and fasting glucose reaching target values (χ2 likelihood ratio = 8.36, P = 0.004) but not for afternoon or evening SMBG (all P > 0.1). Postprandial SMBGs were also improved during the IF phase, with 60.5% readings below 9.05 mmol/L, compared

关键词： Intermittent fasting Type 2 diabetes Remote food photography Self-monitored blood glucose Homeostasis model of assessment for insulin resistence index

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Numerical simulation of a sheet metal extrusion process by using thermal-mechanical coupling EAS FEM

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Journal of University of Science and Technology Beijing 2002年第5期9卷 378-382页

作者： Zhanghuachen T.c.Lee 等 AppliedScienceSchool UniversityofScienceandTechnologyBeijingBeijing100083China DepartmentofIndustrialsystemEngineering TheHongKongPolytechnicunivetsityChina

The thermal-mechanical coupling finite element method(FEM)was usedto simulate a non-isothermal sheet metal extrusion process. On thebasis of the finite plasticity consistent with multiplicativedecomposition of the deformation gradient, the enhanced as- sumedstrain(EAS)FEM was applied to carry out the numerical simulation. Inorder to make the computation reliable ad avoid hour- glass mode inthe EAS element under large compressive strains, an alterative formof the original enhanced deformation gradient was employed. Inaddition, reduced factors were used in the computation of the elementlocal internal parameters and the enhanced part of elementalstiffness.

关键词： enhanced assumed strain element thermal-mechanical coupling process houyrglass mode

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