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Freeze-thaw cycles and associated geomorphology in a post-glacial environment:current glacial,paraglacial,periglacial and proglacial scenarios at Pico de Orizaba volcano,mexico

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Journal of mountain Science 2024年第6期21卷 1954-1977页

作者： Víctor SOTO Carlos m.WELSH R. Kenji YOSHIKAWA Hugo DELGADO GRANADOS Centro de Ciencias de la Tierra Universidad VeracruzanaCircuito Gonzalo Aguirre BeltránS/NZona Universitaria91090XalapaMéxico Water and Environmental Research Center University of Alaska FairbanksFairbanksAlaska 99775USA Instituto de Geofísica Universidad Nacional Autónoma de MéxicoCiudad de México 04150México Department of Earth and Environmental Sciences Ludwig Maximilians UniversitätMunich 80333Germany

The glacial history of Pico de Orizaba indicates that during the Last Glacial maximum,its icecap covered up to~3000 m asl;due to the air temperature increasing,its main glacier has retreated to 5050 m *** retraction of the glacier has left behind an intense climatic instability that causes a high frequency of freeze-thaw cycles of great intensity;the resulting geomorphological processes are represented by the fragmentation of the bedrock that occupies the upper parts of the *** is a notable lack of studies regarding the fragmentation and erosion occurring in tropical high mountains,and the associated geomorphological risks;for this reason,as a first stage of future continuous research,this study analyzes the freezing and thawing cycles that occur above 4000 m asl,through continuous monitoring of surface ground *** results allow us to identify and characterize four zones:glacial,paraglacial,periglacial and *** was found that the paraglacial zone presents an intense drop of temperature,of up to~9℃ in only sixty *** rock fatigue and intense freeze-thaw cycles that occur in this area are responsible for the high rate of rock disintegration and represent the main factor of the constant slope dynamics that occur at the *** activity decreases,both in frequency and intensity,according to the distance to the glacier,which is where the temperature presents a certain degree of stability,until reaching the proglacial zone,where cycles are almost non-existent,and therefore there is no gelifraction *** geomorphological processes have resulted in significant alterations to the mountain slopes,which can have severe consequences in terms of risk and water.

关键词： Freeze-Thaw Gelifraction mountain mechanical erosion Periglacial geomorphology Postglacial scenarios

microstructure characteristics and effect of grain orientation on magnetic properties of Fe_(63)Co_(32)Gd_5 alloy ribbons

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Journal of Central South University 2015年第6期22卷 2014-2019页

作者：姚文静王楠 LEE je-hyun Key Laboratory of Space Applied Physics and Chemistry of ministry of Education School of Science Northwestern Polytechnical University Engineering Research Center for Integrated mechatronics materials and Components Changwon National University

By using the melt spinning techniques, the Fe63Co32Gd5 alloy ribbons with 15-50 m in thickness and 3-7 mm in width were prepared at the wheel speeds of 15, 20, 25 and 35 m/s. The rapid solidification microstructures were characterized by three layers, the middle layer of which reaches 80% thickness and forms the column grain of(Fe,Co) solid with Gd solution. Grain refinement takes place with the increase of the wheel speed. And after 0.5 h heat treatment at 823 K, the ribbon thickness becomes larger and the middle layer of column grain is very orderly perpendicular to the ribbon plane. The coercivity of quenched and annealed Fe63Co32Gd5 ribbons both have the inflection point at the wheel speed of 20 m/s, and the tendency is declining. The heat treatment processing makes the coercivity become lower by improving the order of(Fe,Co)17Gd2 compound. The saturation magnetization of quenched ribbons increases with the enhancement of wheel speed, whereas that of annealed ones decreases firstly and then increases. The minimum coercivity is 5.30×103 A/m and the maximum saturation magnetization is 163.62 A·m2/kg, which is obtained in the conditions of the wheel speed of 35 m/s and 0.5 h heat treatment at the temperature of 823 K.

关键词： Fe-Co-Gd alloy ribbon rapid solidification phase composition magnetic properties

Exact solutions for magnetohydrodynamic nanofluids flow and heat transfer over a permeable axisymmetric radially stretching/shrinking sheet

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Chinese Physics B 2024年第2期33卷 108-114页

作者： U.S.mahabaleshwar G.P.Vanitha L.m.Pérez Emad H.Aly I.Pop Department of Studies in mathematics Davangere UniversityShivagangothriDavangereIndia Departamento de F´ısica FACIUniversidad de Tarapac´aCasilla 7DAricaChile Department of mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt Department of mathematics Babes-Bolyai University400084 Cluj-NapocaRomania

We report on the magnetohydrodynamic impact on the axisymmetric flow of Al_(2)O_(3)/Cu nanoparticles suspended in H_(2)O past a stretched/shrinked *** the use of partial differential equations and the corresponding thermophysical characteristics of nanoparticles,the physical flow process is *** resultant nonlinear system of partial differential equations is converted into a system of ordinary differential equations using the suitable similarity *** transformed differential equations are solved *** of the magnetic parameter,solid volume fraction and stretching/shrinking parameter on momentum and temperature distribution have been analyzed and interpreted *** skin friction and Nusselt number were also *** addition,existence of dual solution was deduced for the shrinking sheet and unique solution for the stretching ***,Al_(2)O_(3)/H_(2)O nanofluid flow has better thermal conductivity on comparing with Cu/H_(2)O ***,it was found that the first solutions of the stream are stable and physically realizable,whereas those of the second ones are unstable.

关键词： magnetohydrodynamic nanofluid stretching/shrinking sheet axisymmetric flow analytical solution suction/injection

The Energy Performance in the Italian Public Administration： State of the Art and Future Prospects

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Economics World 2017年第6期5卷 553-559页

作者： Omella malandrino Daniela sica University of Salerno Salerno Italy Stefania Supino San Raffaele University Rome Italy

The commitment to improve energy and environmental performance in public administration is essential for the success of development models geared towards lasting sustainability. The Public Administration （PA） in Italy, in particular, plays a key role to affn-m models of development oriented towards energy and environmental sustainability, thanks to a wider and more innovative vision. The PA has a dual consumer/user role, public heritage and decision maker/planner, in promoting energy efficiency at local level, in the light of specific problems and peculiarities. For several decades, initiatives have been launched at various levels to improve energy and environmental performance in the public administration. The aim of this study is to outline from a critical perspective, the state of the art of policy makers in Italy concerning energy efficiency measures in public administration. There are however many cultural, value-related, financial, technological, institutional, and operational issues in the PA sector that limit investments in energy efficiency. It should be noted that if on one hand the PA shows a lack of knowledge and is unwilling to adopt practices and systemic tools for monitoring and control, on the other, in terms of bureaucracy, the system appears to be far too complicated and costly. The multiple benefits linked to improved energy performance would therefore require that the PA rethink their organizational and functional models, put in place more flexible and less bureaucratic forms of management and a more dynamic, pervasive, and proactive approach towards initiatives that promote energy efficiency. The research is a contribution towards identifying the driving forces behind potential systems and tools for energy efficiency in the PA, highlighting both critical elements and opportunities and, in particular, the limits deriving from the technological, managerial, and organizational options available for energy eff^ciency enhancement in the sector of the

关键词： energy efficiency Public Administration policy maker sustainability development low carbon economy energy performance

metal-modulated epitaxy of mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto Hernández-Gutiérrez Enrique Campos-González máximo López-López Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with mg by plasma-assisted molecular beam epitaxy(PAmBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(mmE)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBL)in LED *** varied the Al composition in the EBL from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SILVACO *** results from this study highlight the importance and capability of producing high-quality mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-LED EBL simulation

A taxonomic review of the genus miaenia Pascoe, 1864(Coleoptera: Cerambycidae) from South Korea with a new record of m. tonsa(Bates)

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Journal of Forestry Research 2018年第3期29卷 822-829页

作者： Ik je Choi Tae Sung Kwon Jongok Lim Silkworm and Insect management Center Gyeongsangbuk-do Agricultural Resource Management Institute Forest Insect Pests and Disease Division Korea Forest Research Institute Division of Forest Biodiversity Korea National Arboretum

The cerambycid genus miaenia Pascoe(Coleoptera: Cerambycoidea) of South Korea is taxonomically reviewed. Two species, miaenia fasciata fasciata(matsushita) and miaenia maritima Tsherepanov have been recorded. In this paper, m. tonsa(Bates) is added to the Korean cerambycid fauna for the first time. A key to Korean miaenia species, re-description and diagnostic illustrations, including male genitalia for each species, are provided.

关键词： Acanthocinini Cerambycidae miaenia New species South Korea Taxonomy

Further investigation on the fusion of ^(6)Li with ^(209)Bi target at near-barrier energies

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Chinese Physics C 2024年第7期48卷 106-117页

作者：张高龙焦振威张广鑫 m.R.Cortes 胡世鹏钱建强 D.mengoni 屈卫卫李聪博郑云张焕乔孙慧斌王楠张春雷 J.J.Valiente-Dobón D.Testov m.mazzocco A.Gozzelino C.Parascandolo D.Pierroutsakou m.La Commara A.Goasduff D.Bazzacco D.R.Napoli F.Galtarossa F.Recchia A.Illana S.Bakes I.Zanon S.Aydin G.de Angelis m.Siciliano R.menegazzo S.m.Lenzi J.L.Ferreira J.Rangel Serkan Akkoyun L.F.Canto J.Lubian School of Physics Beihang UniversityBeijing 100191China Sino-French Institute of Nuclear Engineering and Technology Sun Yat-Sen UniversityZhuhai 519082China Instituto de Física Universidade Federal Fluminense24210-340NiteróiRio de JaneiroBrazil Institute for Advanced Study in Nuclear Energy&Safety Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Research and manufacture of High Purity Germanium materials and Fetectors Shenzhen UniversityShenzhen 518060China INFN Sezione di PadovaPadovaItaly Dipartimento di fisica Astronomia dell'Universita di padova PadovaItaly State Key Laboratory of Radiation medicine and Protection School of Radiation Medicine and ProtectionSoochow UniversitySuzhou 215123China China Institute of Atomic Energy Beijing 102413China The Key Laboratory of Beam Technology and material modification of ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China INFN Laboratori Nazionali di LegnaroI-35020 LegnaroItaly INFN Sezione di NapoliI-80126 NapoliItaly Dipartimento di Farmacia Universitàdi Napoli"Federico II"I-80131 NapoliItaly Department of Natural and mathematical Sciences Faculty of EngineeringTarsus University33480 MersinTurkiye Physics Division Argonne National LaboratoryLemont-ILUSA Departamento de matemaética Física e Computaç˜ao Universidade do Estado do Rio de JaneiroFaculdade de Tecnologia27537-000ResendeRio de JaneiroBrazil Department of Physics Sivas Cumhuriyet UniversitySivasTurkey Instituto de Física Universidade Federal do Rio de JaneiroCP 6852821941-972Rio de JaneiroBrazil

The complete and incomplete fusion cross sections for ^(6)Li+^(209)Bi were measured using the in-beamγ-ray method around the Coulomb *** cross sections of(deuteron captured)incomplete fusion(ICF)products were re-quantified experimentally for this reaction *** results reveal that the ICF cross section is equivalent to that of complete fusion(CF)above the Coulomb barrier and dominant near or below the Coulomb barrier.A theoretical calculation based on the continuum discretized coupled channel(CDCC)method was performed for the aforementioned CF and ICF cross sections;the result is consistent with the *** universal fusion function(UFF)was also compared with the measured CF cross section for different barrier parameters,demonstrating that the CF suppression factor is significantly influenced by the choice of potential,which can reflect both dynamic and static effects of breakup on the fusion process.

关键词： cross section incomplete fusion suppression factor weakly bound nuclei

Role of serotonin in development of esophageal and gastric fundal varices

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World Journal of Gastroenterology 2010年第48期16卷 6135-6138页

作者： jelena S Rudi Dorde m ulafi Duko S mirkovi Rada S jei miodrag N Krsti Clinic of Gastroenterology Clinical Center of SerbiaFaculty of MedicineUniversity of Belgrade Centre of medical Biochemistry Clinical Center of SerbiaSchool of PharmacyUniversity of Belgrade

AIm:To determine the effect of free serotonin concentrations in plasma on development of esophageal and gastric fundal varices. mETHODS:This prospective study included 33 patients with liver cirrhosis and 24 healthy controls. Ultrasonography and measurement of serotonin concentration in plasma were carried out in both groups of subjects. The upper fiber panendoscopy was performed only in patients with liver cirrhosis. RESULTS:The mean plasma free serotonin levels were much higher in liver cirrhosis patients than in healthy controls (219.0 ± 24.2 nmol/L vs 65.4 ± 18.7 nmol/L,P ma and the size of the esophageal varices according to Spearman coefficient of correlation (rs =-0.217,P > 0.05). However,the correlation of plasma serotonin concentration and gastric fundal varices was highly significant (rs =-0.601,P ment of fundal varices,indicating the clinical value of serotonergic receptor blockers in these patients.

关键词： Serotonin Portal hypertension Esophageal varices Fundal varices Platelets

In vivo antiplasmodial activities of ethanolic exract and fractions of Eleucine indica

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Asian Pacific Journal of Tropical medicine 2012年第9期5卷 673-676页

作者： Ettebong EO Nwafor PA Okokon je Department of Pharmacology and Toxicology Faculty of PharmacyP.M.B.1017University of UyoUyoNigeria

Objective:To evaluate the in rivo antiplasmodial activities of the extract and fractions(n-hexane. chloroform,***) of the whole plant in Plasmodium berghei berghei infected ***:Oral administrations of the extract(200.400,and 600 my/kg) of Eleacine indica and fractions(400 mg/kg) were screened in the *** and curative tests. Chloroquine(5 mg/kg).pyrimethamine(1.2 mg/kgi and artesunate(5 mg/kgi were used as controls. Results:The extract showed significant[Pmodial activity in the *** and curative tests and increased the survival times of the infected mice. All the fractions exhibited significant antiplasmodial activity with the highest being ethylacetate ***:Eleucine indica extract and fractions possess antimalarial activity which confirms the ethnobotanical use of this plant as a malarial remedy and opens a new highway to further investigate its potentials in the on-going fight against malaria.

关键词： Antimalarial activity Alkaloid Plasmodium berghei berghei Eleucine indica