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Impact of the Brink-Axel hypothesis on unique first-forbiddenβ-transitions for r-process nuclei

Chinese Physics C 2024年第3期48卷 148-168页

作者： Fakeha Farooq Jameel-un Nabi Ramoona Shehzadi Department of Physics University of the PunjabQuaid-e-Azam Campus 54590LahorePakistan university of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

Key nuclear inputs for the astrophysical r-process simulations are the weak interaction ***,the accuracy of these inputs directly affects the reliability of nucleosynthesis *** majority of the stellar rates,used in simulation studies are calculated by invoking the Brink-Axel(BA)*** BA hypothesis assumes that the strength functions of all parent excited states are the same as for the ground state,only shifted in ***,the BA hypothesis has to be tested against microscopically calculated state-by-state *** this project,we study the impact of the BA hypothesis on calculated stellarβ^(-)-decay and electron capture *** investigation include both unique first forbidden(U1F)and allowed transitions for 106 neutron-rich trans-iron nuclei([27,77]≤[Z,A]≤[82,208]).The calculations were performed using the deformed proton-neutron quasiparticle random-phase approximation(pn-QRPA)model with a simple plus quadrupole separable and schematic ***-point and several key r-process nuclei lie within the considered mass region of the nuclear *** computed electron capture andβ^(-)-decay rates using two different prescriptions for strength *** was based on invoking the BA hypothesis and the other was the state-by-state calculation of strength functions,under stellar density and temperature conditions([10,1]≤[ρYe(g/cm^(3)),T(GK)]≤[10^(11),30]).Our results show that the BA hypothesis invoked U1Fβ^(-)rates are overestimated by 4–5 orders of magnitude as compared to microscopic *** capture rates,more than two orders of magnitude differences were noted when applying the BA *** was concluded that the BA hypothesis is not a reliable approximation,especially forβ^(-)-decay forbidden transitions.

关键词： Brink-Axel hypothesis pn-QRPA model unique first forbiddenβ-transitions GT strength functions trans-iron nuclei r-process

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Radiative capture of proton through the ^(14)N(p,γ)^(15)O reaction at low energy

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Chinese Physics C 2024年第4期48卷 183-192页

作者： B.F.Irgaziev Abdul Kabir Jameel-un Nabi National university of Uzbekistan Tashkent 100174Uzbekistan Space and Astrophysics Research lab National Centre of GIS and Space ApplicationsDepartment of Space ScienceInstitute of Space TechnologyIslamabad 44000Pakistan university of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

The CNO cycle is the main source of energy in stars more massive than our *** process defines the energy production,the duration of which can be used to determine the lifetime of massive *** cycle is an important tool for determining the age of globular *** proton capture via p+^(14)N→^(15)O+γ,at energies of astrophysical interest,is an important process in the CNO *** this project,we apply a potential model to describe both non-resonant and resonant reactions in the channels where radiative capture occurs through electric E1 *** employed the R-matrix method to describe the ongoing reactions via M1 resonant transitions,when it was not possible to correctly reproduce the experimental data using the potential *** partial components of the astrophysical S-factor are calculated for all possible electric and magnetic dipole transitions in ^(15)*** linear extrapolated S-factor at zero energy(S(0))agrees well with earlier reported values for all transition types considered in this *** on the value of the total astrophysical S-factor,depending on the collision energy,we calculate the nuclear reaction rates for p+^(14)N→^(15)O+γ.The computed rates agree well with the results reported in the NACRE II Collaboration and most recent existing measurements.

关键词： CNO cycle potential model R-matrix method cross-section astrophysical S-factor nuclear rates.

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Effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on tensile and bending properties of high-Al-containing Mg alloys

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Journal of Magnesium and Alloys 2024年第2期12卷 779-793页

作者： Sumi Jo Gyo Myeong Lee Jong un Lee Young Min Kim Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Department of Magnesium Korea Institute of Materials ScienceChangwon 51508Republic of Korea

This study investigates the effect of characteristics and distribution of Mg_(17)Al_(12)precipitates on the uniaxial tensile and three-point bending properties of extruded Mg alloys containing high Al *** extruded Mg–9Al–1Zn–0.3Mn(AZ91)alloy contains lamellar-structured Mg_(17)Al_(12)discontinuous precipitates along the grain boundaries,which are formed via static precipitation during natural air *** extruded Mg–11Al–1Zn–0.3Mn(AZ111)alloy contains spherical Mg_(17)Al_(12)precipitates at the grain boundaries and inside the grains,which are formed via dynamic precipitation during *** to inhomogeneous distribution of precipitates,the AZ111 alloy consists of two different precipitate regions:precipitate-rich region with numerous precipitates and finer grains and precipitate-scarce region with a few precipitates and coarser *** AZ111 alloy exhibits a higher tensile strength than the AZ91 alloy because its smaller grain size and more a.undant precipitates result in stronger grain-boundary hardening and precipitation hardening effects,***,the tensile elongation of the AZ111 alloy is lower than that of the AZ91 alloy because the weak cohesion between the dynamic precipitates and the matrix facilitates the crack initiation and *** bending,a macrocrack initiates on the outer surface of bending specimen in both *** AZ111 alloy exhibits higher bending yield strength and lower failure bending strain than the AZ91 *** bending specimens of the AZ91 alloy have similar bending formability,whereas those of the AZ111 alloy exhibit considerable differences in bending formability and crack propagation behavior,depending on the distribution and number density of precipitates in the *** bending specimens of the AZ111 alloy,it is found that the failure bending strain(ε_(f,bending))is inversely proportional to the area fraction of precipitates in the outer zone of bending specimen(A_(ppt)),with a relation

关键词： Mg–Al alloy Extrusion Bending Precipitation Microstructure

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Dinitrophenyl-oxadiazole compounds:Design strategy,synthesis,and properties of a series of new melt-cast explosives

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Defence Technology（防务技术） 2024年第5期35卷 100-107页

作者： Bao-long Kuang Ting-wei Wang Cong Li Mou Sun Qamar-un-Nisa Tariq Chao Zhang Zhi-ming Xie Zu-jia Lu Jian-guo Zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081China China Wuzhou Engineering Group CO. LTD.Beijing 100053China

Melt-cast explosives are the most widely used energetic materials in military composite explosives,researchers have been unremittingly exploring high-energy and insensitive melt-cast *** this work,a series of dinitrophenyl-oxadiazole compounds were designed and *** compounds have an ideal low melting point(80-97℃),good detonation performance(detonation velocity D=6455-6971 m/s,detonation pressure P=18-19 GPa)and extreme insensitive nature(impact sensitivity≥60 J,friction sensitivity>360 N).All these compounds were well characterized by nuclear magnetic resonance,fourier transform infrared spectroscopy,elemental *** 2,3 were unambiguously confirmed by X-ray single crystal diffraction *** a result,their overall properties are superior to traditional melt-cast explosives trinitrotoluene(TNT)and dinitroanisole(DNAN)which may have excellent potential applications in insensitive melt-cast explosives.

关键词： Dinitrophenyl-oxadiazole Melt-cast explosive Low sensitivity

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Chemical and mechanical properties of stainless, environment-friendly, and nonflammable Mg alloys (SEN alloys): A review

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Journal of Magnesium and Alloys 2024年第3期12卷 841-872页

作者： Jong un Lee Hyun Ji Kim Sang-Cheol Jin Ye Jin Kim Young Min Kim Bong Sun You Jun Ho Bae Sung Hyuk Park Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Metallurgical Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Missile Research Institute Agency for Defense DevelopmentDaejeon 34060Republic of Korea

This review article provides overall understanding of stainless,environment-friendly,and nonflammable Mg alloys(SEN alloys)recently developed at the Korea Institute of Materials *** alloys are produced by adding small amounts of Ca and Y(eachunts of Ca and Y renders excellent mechanical properties due to improved strengthening *** enhanced properties are attributed to more pronounced dynamic recrystallization and grain refining behaviors caused by the second-phase particles during extrusion.(4)Despite the presence of various types of second-phase particles,the fatigue properties of SEN9 alloys are similar to those of commercial AZ91 alloys.(5)Simultaneous introduction of Ca and Y suppresses the formation of Mg17Al12 discontinuous precipitates during aging,leading to the enhanced elongation of aged SEN alloys.(6)Adding mischmetal into the SEN9 alloy leads to a six-fold enhancement in ***,the studies conducted on SEN alloys demonstrate their excellent ignition and corrosion resistances and mechanical properties,which broaden the industrial applications of Mg alloys by addressing their inherent weaknesses.

关键词： SEN magnesium alloy Corrosion resistance Ignition resistance Mechanical properties Extrudability.

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Protein Arginine Methyltransferase 1 Ablation in Motor Neurons Causes Mitochondrial Dysfunction Leading to Age-related Motor Neuron Degeneration with Muscle Loss

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Research 2024年第1期2023卷 637-649页

作者： Hyun-Kyung So Hyebeen Kim Jinwoo Lee Chang-Lim You Chae-Eun Yun Hyeon-Ju Jeong Eun-Ju Jin Yunju Jo Dongryeol Ryu Gyu-un Bae Jong-Sun Kang Department of Molecular Cell Biology Sungkyunkwan University School of MedicineSuwonKorea Single Cell Network Research Center Sungkyunkwan University School of MedicineSuwonKorea Research Institute of Aging-Related Diseases AniMusCureInc.SuwonKorea Drug Information Research Institute Muscle Physiome Research CenterCollege of PharmacySookmyung Women’s UniversitySeoulKorea

Neuromuscular dysfunction is tightly associated with muscle wasting that occurs with age or due to degenerative ***,the molecular mechanisms underlying neuromuscular dysfunction are currently *** studies have proposed important roles of Protein arginine methyltransferase 1(Prmt1)in muscle stem cell function and muscle *** the current study,we set out to determine the role of Prmt1 in neuromuscular function by generating mice with motor neuron-specific ablation of Prmt1(mnKO)using *** exhibited age-related motor neuron degeneration and neuromuscular dysfunction leading to premature muscle loss and ***1 deficiency also impaired motor function recovery and muscle reinnervation after sciatic nerve *** transcriptome analysis of aged mnKO lumbar spinal cords revealed alterations in genes related to inflammation,cell death,oxidative stress,and ***,mnKO lumbar spinal cords of sciatic nerve injury model or aged mice exhibited elevated cellular stress response in motor ***,Prmt1 inhibition in motor neurons elicited mitochondrial *** findings demonstrate that Prmt1 ablation in motor neurons causes agerelated motor neuron degeneration attributing to muscle ***,Prmt1 is a potential target for the prevention or intervention of sarcopenia and neuromuscular dysfunction related to aging.

关键词： degeneration impaired prevention

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柬埔寨福建会馆民生学校发展现状中的语言定性偏差问题研究

柬埔寨福建会馆民生学校发展现状中的语言定性偏差问题研究

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作者：黄佩玲（un SORIYA）华东师范大学

学位级别：硕士

柬埔寨目前共有50余所华校,其中端华学校、民生学校、崇正学校、广肇学校称之为柬埔寨四大华校。这四所华校在生源、办学规模、教学质量上等都占有优势。民生学校作为柬埔寨较权威的华校之一,自从1999年复课以来,也同其他华校一样一直... 详细信息

柬埔寨目前共有50余所华校,其中端华学校、民生学校、崇正学校、广肇学校称之为柬埔寨四大华校。这四所华校在生源、办学规模、教学质量上等都占有优势。民生学校作为柬埔寨较权威的华校之一,自从1999年复课以来,也同其他华校一样一直沿用传统的办学模式,误把“汉语”当作学生的第一语言来进行教授,而采用的教学方法主要以“教授型”为主。由于民生学校的语言定性偏差而给教学上带来了诸多问题,例如:重复教学、过于注重语言的本体,而忽视语言的技能等,导致该校学生难于用汉语来进行交际。目前民生学校正处于瓶颈阶段,该校的办学体系不完整(最高年级是九年级),且学历不被承认。基于民生学校的自身特色,笔者认为对该校进行研究,颇有研究价值。本文以民生学校的校领导、本土中文教师及学生作为研究对象。通过资料收集、访谈、问卷调查等方法,探讨及分析了该校的语言定性偏差所带来的问题,试图帮助民生学校寻找解决问题的方法。研究得出的结论是民生学校该走向改革的新道路——办成全日制柬中双语学校,以柬文的教育体系作为主流(学生可以参加全柬的高考,以其作为升学依据),而汉语则作好与柬文的接应工作,并以第二语言教学法进行教授。办成全日制柬中双语学校有助于民生学校早日纳入主流教育体系,同时还可以让民生学校摆脱“学历不被承认”的困扰,而且学生缺课严重、年龄参差不齐等问题也能解决。

关键词：柬埔寨华校民生学校语言定性第二语言

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考虑间隙水体阻尼修正的过驳双船系统动力响应研究

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船舶力学 2024年第6期28卷 856-865页

作者：刘利琴刘依伦王岭郭颖孟春蕾天津大学水利工程仿真与安全国家重点实验室天津300072 天津航海仪器研究所天津300131

利用阻尼修正的势流理论对过驳双船系统进行研究。建立了过驳双船系统CFD数值计算模型,通过在双船间隙自由水面施加粘性阻尼盖的方法对势流理论进行修正。对双船过驳系统在考虑与不考虑修正两种情况下的时域结果进行对比分析,结果表明:... 详细信息

利用阻尼修正的势流理论对过驳双船系统进行研究。建立了过驳双船系统CFD数值计算模型,通过在双船间隙自由水面施加粘性阻尼盖的方法对势流理论进行修正。对双船过驳系统在考虑与不考虑修正两种情况下的时域结果进行对比分析,结果表明:双船各自由度的运动响应以及各系缆护舷的受力,在不计及粘性修正时的计算结果皆高于修正后的结果,因而考虑流体粘性的修正是非常必要的。

关键词：过驳系统粘性修正时域分析势流理论

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Prediction of characteristic blast-induced vibration frequency during underground excavation by using wavelet transform

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Frontiers of Structural and Civil Engineering 2022年第8期16卷 1029-1039页

作者： Tae un PAK Guk Rae JO un Chol HAN Faculty of Mining Engineering Kim Chaek University of TechnologyPyongyang 999093Democratic People’s Republic of Korea School of Science and Engineering Kim Chaek University of TechnologyPyongyang 999093Democratic People’s Republic of Korea

Blast-induced vibration produces a very complex signal,and it is very important to work out environmental problems induced by *** this study,blasting vibration signals were measured during underground excavation in carbonaceous shale by using vibration pickup CB-30 and FFT analyzer ***,wavelet analysis on the measured results was carried out to identify frequency bands reflecting changes of blasting vibration parameters such as vibration velocity and energy in different frequency *** characteristics are then discussed in view of blast source distance and charge weight per *** analysis of results,it can be found that peak velocity and energy of blasting vibration in frequency band of 62.5–125 Hz were larger than ones in other bands,indicating the similarity to characteristics in the distribution band(31–130 Hz)of main vibration *** frequency bands were affected by blasting source distance,and the frequency band of 0–62.5 Hz reflected the change of charge weight per *** presenting a simplified method to predict main vibration frequency,this research may provide significant reference for future blasting engineering.

关键词： wavelet analysis blast-induced vibration frequency characteristics underground excavation

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“三个务必”融入高校思政课教学的价值与实践

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苏州科技大学学报（社会科学版） 2024年第1期41卷 25-31,107页

作者：孙崇明温波苏州科技大学马克思主义学院江苏苏州215009

党的二十大报告首次提出“三个务必”,这既是对新时代新征程中全体党员的引领与塑造,也是重要的思政课教学资源。“三个务必”融入高校思政课教学是落实思政课立德树人根本任务的育人使命,是挖掘“三个务必”思想教育资源的教学之需,是... 详细信息

党的二十大报告首次提出“三个务必”,这既是对新时代新征程中全体党员的引领与塑造,也是重要的思政课教学资源。“三个务必”融入高校思政课教学是落实思政课立德树人根本任务的育人使命,是挖掘“三个务必”思想教育资源的教学之需,是引导青年学生抵御和反对“躺平”无为的时代诉求。要创造性地将“三个务必”融入高校思政课教学,就要明确立德树人的教学目标;促进“三个务必”理论成果向教学内容转化;丰富运用课堂叙事、探索启发、社会体验等教学方法;以“四个熔铸”教学格局整体提升高校思政课贯彻落实“三个务必”的能力和水平。

关键词： “三个务必” 高校思政课

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