检索结果-南通市图书馆

Astrophysical S-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

Chinese Physics C 2024年第4期48卷 130-145页

作者： S.B.Dubovichenko A.S.Tkachenko R.ya.Kezerashvili N.A.Burkova B.m.yeleusheva Fesenkov Astrophysical Institute 050020 AlmatyKazakhstan New york City College of Technology City University of New YorkBrooklyn11201 New YorkUSA Graduate School and University Center City University of New York10016 New YorkUSA al-Farabi Kazakh National University 050040 AlmatyKazakhstan

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(mPCm)with forbidden states,including low-lying *** investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)S_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)m1 *** calculated the astrophysical low-energy S-factor,and the extrapolated S(0)turned out to be within 34.7−40.4 keV·*** important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances is elucidated.A comparison of our calculation for the S-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is *** reaction rate is calculated and compared with the existing *** has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances in reference to the CNO Gamow windows,especially at low *** estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from ***.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=*** present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the mPCm and provide the temperature windows,prevalence,and significance of each process.

关键词： low and astrophysical energies p^(15)N system thermonuclear reaction rate potential cluster model CNO-cycle

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Spatiotemporal oxygen dynamics in young leaves reveal cyclic hypoxia in plants

引用

molecular Plant 2024年第3期17卷 377-394页

作者： Paolo m.Triozzi Luca Brunello Giacomo Novi Gianmarco Ferri Francesco Cardarelli Elena Loreti mariano Perales Pierdomenico Perata PlantLab Center of Plant SciencesSant'Anna School of Advanced Studies56010 PisaItaly Centro de Biotecnologia y Genomica de Plantas Universidad Politecnica de Madrid(UPM)-Instituto Nacional de Investigacion y Tecnologia Agraria y Alimentaria(INIA-CSIC)Campus de Montegancedo UPMPozuelo de Alarcon28223 MadridSpain Fondazione Pisana per la Scienza 56017 PisaItaly Laboratorio NEST Scuola Normale SuperioreIstituto Nanoscienze-CNRPiazza S.Silvestro1256127 PisaItaly institute of Agricultural Biology and Biotechnology National Research Council56124 PisaItaly Departamento de Biotecnologia-Biologia Vegetal Escuela Tecnica Superior de Ingenieria AgronomicaAlimentaria y de BiosistemasUniversidad Politecnica de Madrid(UPM)28040 Madrid.Spain

Oxygen is essential for plant growth and *** occurs in plants due to limited oxygen avail-abilityfollowing adverse environmental conditions as well inhypoxic niches in otherwisenormoxic ***,the existence and functional integration of spatiotemporal oxygen dynamics with plant development remains *** animal systems dynamic fluctuations in oxygen availability are known as cyclic *** this study,we demonstrate that cyclic fluctuations in internal oxygen levels occur in young emerging leaves of Arabidopsis *** hypoxia in plants is based on a mechanism requiring the ETHyLENE RESPONSE FACTORS type VII(ERFVII)that are central components of the oxygen-sensing machinery in *** ERFVll-dependent mechanism allows precise adjustment of leaf growth in response to carbon status and oxygen availability within plant *** study thus establishes a functional connection between internal spatiotemporal oxygen dynamics and developmental processes of plants.

关键词： Arabidopsis hypoxia cyclic hypoxia leaf development oxygen-sensing mechanism ERFVII

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effect of samarium oxide on structural,optical and electrical properties of some alumino-borate glasses with constant copper chloride

引用

Journal of Rare Earths 2020年第7期38卷 770-775,I0004页

作者： m.S.Sadeq H.y.morshidy Basic Sciences Dept. Faculty of EngineeringSinai Univ.45511Al-ArishEgypt

The glass system under study was prepared and examined using the melt quenching procedures and XRD to emphasize the amorphous nature,*** of the prepared solid glass system was performed by a spectrophotometer in wavelengths from 190 to 1099 *** traditional techniques and standard formulas,the density,molar volume,refractive index,optical band gap and the optical filter characteristics were determined,then the influence of samarium oxide on some properties like the structure and optical,also the electrical properties were dissected.A novel formula was proposed to estimate the refractive index from the optical energy *** obtained samples are good optical filters especially the sample that contains 0.8 mol% of Sm2 *** this sample has the utmost density,the least molar volume,the maximum transmittance,least refractive index,the highest optical band gap and the least dc conductivity.

关键词： Alumino borate glasses Samarium oxide Optical properties Rare earths

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Low temperature oxidation of Cr-alloyed moSi_2

引用

中国有色金属学会会刊：英文版 2007年第6期17卷 1282-1286页

作者： E. Strom y. Cao y. m. yao Kanthal AB Box 502 SE-734 27 Hallstahammar Sweden Department of materials and manufacturing Technology Chalmers University Technology SE-412 96 Gothenburg Sweden

Cr-alloyed moSi2 was compared with monolithic moSi2 with respect to oxidation at 450 ℃ for 456 h. Phases formed on Cr-alloyed moSi2 after exposure are Cr2(moO4)3, moO3, and cristobalite (SiO2) according to X-ray diffraction results. monolithic moSi2 forms moO3 and mainly amorphous SiO2. X-ray photoelectron spectroscopy indicates that the main oxidation product on the outermost surface is SiO2 for all studied samples. The samples form a relatively loose oxide but the oxide adherence improves with increasing Cr content. It is indicated that Cr addition can benefit pesting control in moSi2.

关键词：钼硅化合物合金有害物氧化作用

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Parameter Optimisation of Stress-strain Constitutive Equations Using Genetic Algorithms

引用

Journal of materials Science & Technology 2003年第z1期19卷 5-8页

作者： y. y. yang m. mahfouf D.A.Linkens Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK Department of Automatic Control and Systems Engineering University of Sheffield Mappin St. Sheffield S1 3JD UK

The accuracy of numerical simulations and many other material design calculations, such as the rolling force, rollingtorque, etc., depends on the description of stress-strain relationship of the deformed materials. One common methodof describing the stress-strain relationship is using constitutive equations, with the unknown parameters fitted byexperimental data obtained via plane strain compression (PSC). Due to the highly nonlinear behaviour of the constitutive equations and the noise included in the PSC data, determination of the model parameters is difficult. Inthis paper, genetic algorithms were exploited to optimise parameters for the constitutive equations based on thePSC data. The original PSC data were processed to generate the stress-strain data, and data pre-processing wascarried out to remove the noise contained in the original PSC data. Several genetic optimisation schemes have beeninvestigated, with different coding schemes and different genetic operators for selection, crossover and *** was found that the real value coded genetic algorithms converged much faster and were more efficient for theparameter optimisation problem.

关键词： Genetic algorithms, Parameter optimisa tion, Aluminium alloy, Flow stress, Constitutive equations

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

青藏高原及其周边第四纪综合地层、生物群与古地理演化

引用

中国科学：地球科学 2024年第4期54卷 1379-1410页

作者：王永郑绵平凌媛向树元邵兆刚张克信柯学林晓韩芳韩建恩中国地质科学院地质研究所北京100037 中国地质科学院矿产资源研究所北京100037 中国地质大学(武汉)地球科学学院武汉430074 中国地质科学院北京100037 中国地质大学(武汉)地质调查研究院武汉430074 东华理工大学地球科学学院南昌330013 中国地质科学院地质力学研究所北京100081

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉... 详细信息

青藏高原第四纪地层蕴含丰富的古气候与环境演变信息,记录了高原第四纪区域构造、古地理和地貌演化过程,是研究第四纪地质事件和区域环境演变极其重要的地区.根据区域地层资料的综合分析和生物群等的发育演化特征,基于岩石地层单元、沉积特征及地貌、流域水系的差异,将青藏高原及其周边第四纪地层划分为5个地层区:塔里木区、黄土高原区、青藏高原区、云贵高原区及印度-恒河区.并将青藏高原地层区划分为西昆仑-喀喇昆仑分区、阿尔金-祁连山分区、柴达木-河湟分区、东昆仑-巴颜喀拉分区、羌塘分区、藏东-滇西-川西分区及冈底斯-喜马拉雅分区等7个地层分区.简要描述了青藏高原7个地层分区的岩石地层单元,根据各个地层分区的岩石地层序列及其沉积特征、地层接触关系、形成时代与生物群演化,将青藏高原第四纪的构造古地理演化划分为4个阶段:(1) 2.6~1.8/1.5ma,上新世以来继承性差异隆升阶段,区域沉积差异显著,地层分布较局限,沿山前地带普遍发育冲洪积砂砾岩,山间低洼地河湖相沉积发育;(2) 1.8/1.5~1.2/0.8ma,高原整体夷平阶段,高原及周边不整合面广泛分布,大型河流形成,山间盆地及高原腹地发育湖泊沉积物;(3) 1.2/0.8~0.128ma,高原大范围持续隆升,地形差异显著,山体切割加剧,约0.8ma高原进入冰冻圈,山地冰川发育,高寒干旱环境逐步形成;(4)0.128ma~,山体上升与侵蚀切割加剧,山间盆地湖泊广泛分布,区域沉积特征差异较大,沉积类型向多样化发展,现代高原地貌格局基本形成.

关键词：青藏高原第四纪地层对比生物群古地理

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Spin-correlation function of the fully frustrated Ising model and ±J Ising spin glass on a square lattice

引用

Chinese Physics B 2013年第6期22卷 549-552页

作者： m y Ali J Poulter Department of mathematics Faculty of ScienceMahidol University

In this work we study the correlation function of the ground state of a two-dimensional fully frustrated Ising model as well as spin glass. The Pfaffian method is used to calculate free energy and entropy as well as the correlation function. We estimate the exponent of spin correlation function for the fully frustrated model and spin glass. In this paper an overview of the latest results on the spin correlation function is presented.

关键词： spin glass correlation function exponent square lattice

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Provenance and depositional setting of the Late miocenePleistocene clastic sediments in the eastern Arabian Peninsula and western Iraq using rare earth elements geochemistry

引用

Acta Geochimica 2024年第2期43卷 399-410页

作者： Salih m.Awadh Zinah S.Al-Ankaz mohanad R.A.Al-Owaidi John S.Armstrong-Altrin Department of Geology College of ScienceUniversity of BaghdadBaghdadIraq Department of Geology College of ScienceUniversity of WasitWasit 52011Iraq Department of Applied Geology College of ScienceUniversity of BabylonBabylon 51001Iraq Unidad de Procesos Oceanicos y Costeros Instituto de Ciencias del Mar y LimnologíaUniversidad Nacional Autonoma de MexicoCiudad Universitaria04510 Mexico CityCDMXMexico Department of marine Sciences Bharathidasan UniversityTiruchirapalliTamil Nadu 620024India

The sandstones of the Late miocene–Pliocene Dibdibba Formation in the Najaf–Karbala Plateau and Basra were examined to determine their source rocks and origin. The rare earth elements(REE) and trace elements(Sc, Co, V, and Th) concentrations in these sandstones revealed that they likely derived from a single source. The steep light rare earth elements(LREE) and flat, heavy rare earth element(HREE) patterns, negative Eu anomaly, and high ΣREE contents in sandstones suggest its derivation from a suggests that a passive continental margin environment and originated from felsic source rocks. The average concentration of ΣREE is 93.5 ppm, which is lower than that of the average crustal compositions like Upper Continental Crust and Post Archean Australian Shale. The higher proportion of LREE compared to HREE implies that these sandstones were recycled and derived from a distal source. The Th/Co, Th/Sc, La/Sc, La/Co, Eu/Eu*and(La/Lu)cn elemental ratios indicated that these Late miocene–Pliocene sandstones were derived from felsic rocks located in the marginal region of the Arabian Shield.

关键词： REE Dibdibba formation Clastic sediments Passive continental margin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Acceptance of COVID-19 vaccine and its related determinants in Nigeria:An online survey

引用

World Journal of Virology 2024年第4期13卷 89-110页

作者： Eyiuche D Ezigbo Seyi S Enitan Esther N Adejumo Abiodun E Durosinmi Richard y Akele michael O Dada Grace E Itodo Abah m Idoko Okeoghene m Edafetanure-Ibeh Edwin N Okafor Adedeji A Abdulsalam Oyekan I Oyedoyin Polit U yelpoji Ogunwola O Opeyemi Ogbuji S Nmesomachi Adesola O Oyekale Chisom B Onyeji Haemostasis and Thrombosis Unit Department of Medical Laboratory SciencesUniversity of NigeriaEnugu CampusEnuguEN 400241Nigeria Department of medical Laboratory Science School of Public and Allied HealthBabcock UniversityIlishan-RemoOG 121109Nigeria Department of medical Laboratory Science State HospitalIjebu-OdeOG 120221Nigeria Department of Biomedical Science School of Applied ScienceUniversity of BrightonBrightonES BN24ATUnited Kingdom Department of microbiology Federal Teaching Hospital LokojaLokojaKO 260006Nigeria Department of Hematology and Blood Group Serology Federal College of Veterinary and Medical Laboratory TechnologyVomPL 930101Nigeria Department of Environmental and Occupational Health Texas A and M University School of Public HealthGarlandTX 75049United States Division of Chemical Pathology Department of Medical Laboratory SciencesUniversity of NigeriaEnugu CampusEnuguEN 400102Nigeria School of molecular Bioscience Sciences College of MedicalVeterinary and Life SciencesUniversity of GlasgowGlasgowSCO G128QQUnited Kingdom Department of medical Laboratory Science State Hospital Ijebu-OdeIjebu-OdeOG 360101Nigeria Department of medical Laboratory Science Faculty of Health Sciences and TechnologyUniversity of JosJosPL 930103Nigeria Department of medical Laboratory Science Bola Tinubu Health and Diagnostic CenterLagosLA 100102Nigeria Department of Pathology 68 Nigerian Army Reference HospitalYabaLA 1211001Nigeria Department of medical Laboratory Science Ladoke Akintola University of TechnologyOgbomosoOS 2111105Nigeria

BACKGROUND Vaccine hesitancy is a major challenge in the fight against the coronavirus disease 2019(COVID-19)*** the sociodemographic factors associated with vaccine acceptance among Nigerians is crucial for improving vaccine *** To assess the acceptance rate of COVID-19 vaccine and its related determinants among *** An online cross-sectional survey(observational study)was conducted between February 2021 and may 2021,using a questionnaire hosted on *** invitation to take part in the poll was sent out to participants through social networking platforms.A logistic regression was used to determine which sociodemographic factors were associated with vaccine acceptance *** A total of 1800 persons responded to the survey,a larger proportion of whom were males(53.9%)and within the age group of 21-30 years(29.4%)and earned an average income of less than$500 per month(43.3%).Only 0.56%of participants had a high perceived risk of COVID-19 infection,while only 1.11%had a perceived risk of dying from *** perception rate of the COVID-19 vaccine among participants was 51.1%,while the acceptance rate was 63.9%.There was no significant association between the COVID-19 vaccine acceptance rate and related determinants assessed,particularly age(χ²=3.049,P=0.550),sex(χ²=0.102,P=0.749),average income(χ²=3.802,P=0.875),and religion(χ²=2.819,P=0.420).Participants with chronic conditions demonstrated a higher acceptance rate compared to the general *** Despite the positive perception observed and substantial vaccine acceptance rate among the study participants,more public health interventions are still needed to enhance vaccine acceptability in Nigeria.

关键词： Acceptance COVID-19 Determinants Hesitancy Nigerians Online survey Vaccine

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Group classification for path equation describing minimum drag work and symmetry reductions

引用

Applied mathematics and mechanics(English Edition) 2010年第7期31卷 911-916页

作者： m.PAKDEmIRLI y.AKSOy Department of mechanical Engineering Celal Bayar University

The path equation describing the minimum drag work first proposed by Pakdemirli is reconsidered （Pakdemirli, m. The drag work minimization path for a fly- ing object with altitude-dependent drag parameters. Proceedings of the Institution of mechanical Engineers, Part C, Journal of mechanical Engineering Science 223（5）, 1113- 1116 （2009））. The Lie group theory is applied to the general equation. The group classi- fication with respect to an altitude-dependent arbitrary function is presented. Using the symmetries, the group-invariant solutions are determined, and the reduction of order is performed by the canonical coordinates.

关键词： minimum drag work Lie group theory group classification

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：