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Research in Astronomy and Astrophysics 2014年第8期14卷 971-978页

作者： jing-jing liu College of Science and Technology Qiongzhou University

Based on the shell-model Monte Carlo method and random phase approximation theory, the neutrino energy spectrum （NES） and the electron capture （EC） of ^56Fe, ^56Co, ^56Ni, ^56Mn, ^56Cr and ^56V are investigated in presupemova surroundings. The results show that the EC rates are affected greatly at different densities and temperatures. The rates increase greatly and even exceed six orders of magnitude at lower temperature. On the other hand, the NES is very sensitive to stellar temperature and electron energy. The higher the temperature and the lower the electron energy, the larger the influence on NES is. For example, the maxima of NES in the ground state are 9.02, 160, 80, 24.01, 0.44, 1.42 me c^2 for ^56Fe, ^56Co, ^56Ni, ^56Mn, ^56Cr and ^56V respectively at ρ7 = 10.7, ye = 0.45 and T9 = 15. Furthermore, the influence on NES due to EC for different nuclei has some otherness because of different Qo-values. For example, the spectrum of ^56Co shows a double bump structure.

关键词： physical data and processes neutrinos, nuclear reactions -- stars super- novae -- stars evolution

岩芯高光谱成像及勘查指示意义研究--以西藏邦铺大型多金属矿床为例

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光谱学与光谱分析 2025年第1期45卷 38-44页

作者：吴畅宇代晶晶宋扬陈伟刘治博刘洪成白龙洋中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室北京100037 自然资源部深地科学与探测技术实验室中国地质科学院北京100094 核工业北京地质研究院遥感信息与图像分析技术国家级重点实验室北京100029

西藏邦铺矿床是冈底斯成矿带上重要的斑岩-矽卡岩型矿床,矿区东段矽卡岩矿体研究程度较低。高光谱成像技术可以快速获取岩芯样品“图谱合一”的高光谱数据,选取邦铺矿床东段矽卡岩典型岩芯为样品,应用国产核工业北京地质研究院自主研发... 详细信息

西藏邦铺矿床是冈底斯成矿带上重要的斑岩-矽卡岩型矿床,矿区东段矽卡岩矿体研究程度较低。高光谱成像技术可以快速获取岩芯样品“图谱合一”的高光谱数据,选取邦铺矿床东段矽卡岩典型岩芯为样品,应用国产核工业北京地质研究院自主研发岩芯扫描仪与国外SPECIM岩芯成像仪,开展短波红外(SWIR)高光谱成像测试及对比分析,揭示典型矿物的短波红外光谱特征,并探讨先进的高光谱成像技术应用于矽卡岩勘探的潜力与优势。对同一批岩芯样品分别进行了国内外仪器的高光谱成像测试,利用最小噪声分离变换以及纯净像元指数进行端元提取,而后结合光谱信息散度法选取不同矿物的训练集和验证集样本,采用光谱角填图法进行蚀变矿物填图。共识别出方解石、绿帘石、绿泥石、角闪石、石英、白云母六种矿物,两种仪器矿物填图的结果大体一致,并反映了不同蚀变矿物之间的组合与分布。SPECIM成像仪对两个钻孔样品的平均填图精度为91.5%,Kappa系数为0.87;核工业高光谱成像仪对两个钻孔的填图精度为75%左右,Kappa系数为0.66。两种仪器获取的高光谱数据信噪比均较高,但是由于核工业仪器的数据空间分辨率相对更低,导致图像中存在更多的混合像元,进而影响了填图精度,其空间分辨率的进一步提高是下一步研发的重点。高光谱成像数据表明ZK0010钻孔绿泥石Fe-OH吸收峰波长变化范围为2252.3~2260 nm,ZK0011钻孔绿泥石Fe-OH吸收峰变化范围为2251.7~2258.5 nm,由上至下均向短波方向移动,表明了绿泥石远离矿化中心而相对富Mg,其高值指示了矿体中心位置。高光谱成像技术相较于传统的点测法可以提供更加丰富的空间信息和光谱信息,为指针矿物的光谱特征参数提取与变化规律分析提供了技术支撑。利用高光谱成像提供的大量光谱数据进行绿泥石Fe-OH峰位统计分析,进而可以通过其波长高值位置指示矽卡岩矿床勘查。

关键词：岩芯高光谱成像短波红外矽卡岩邦铺

Strong screening effects on resonant nuclear reaction ^(23)Mg(p,γ) ^(24)Al in the surface of magnetars

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Research in Astronomy and Astrophysics 2016年第5期16卷 117-124页

作者： jing-jing liu College of Electronic and Communication Engineering Hainan Tropical Ocean University Department of Astronomy and Institute of Theoretical Physics and Astrophysics Xiamen University

Based on the theory of relativistic superstrong magnetic fields （SMFs）, by using the method of Thomas-Fermi-Dirac approximations, we investigate the problem of strong electron screening （SES） in SMFs and the influence of SES on the nuclear reaction of 23Mg （p, y）24A1. Our calculations show that the nuclear reaction will be markedly effected by the SES in SMFs in the surface of magnetars. Our calculated screening rates can increase two orders of magnitude due to SES in SMFs.

关键词： physical data and processes: nuclear reactions nucleosynthesis abundances -- stars: neutron-- stars: magnetic fields

稀土硼酸盐双折射材料的电子结构和光学性质的第一性原理研究

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原子与分子物理学报 2025年第1期42卷 171-179页

作者：努尔比耶·图尔洪刘鸿涛崔秀花刘静姜轶井群新疆大学物理科学与技术学院乌鲁木齐830017

近年来,稀土(RE)硼酸盐材料因其丰富的结构和优异的光学性质,引起人们广泛关注.使用第一性原理高通量筛选工具获得五个性能优异的短波长稀土硼酸盐材料,并进一步研究了他们的电子结构和光学性质.研究结果表明,这些材料的紫外截止边和双... 详细信息

近年来,稀土(RE)硼酸盐材料因其丰富的结构和优异的光学性质,引起人们广泛关注.使用第一性原理高通量筛选工具获得五个性能优异的短波长稀土硼酸盐材料,并进一步研究了他们的电子结构和光学性质.研究结果表明,这些材料的紫外截止边和双折射率分别为:210 nm,0.0934@1064 nm(LaB_(3)O_(6))、246 nm,0.0880@1064 nm(LaBO_(3))、347 nm,0.0815@1064 nm(LuBO_(3))、272 nm,0.0914@1064 nm(ScBO_(3))、279 nm,0.0920@1064 nm(Sc_(3)B_(5)O_(12)).本文使用投影态密度、实空间原子实切割以及Born有效电荷分析了各原子及离子基团对双折射率的影响机制,结果表明RE-O基团和B-O多面体在决定光学性质方面做出了主要贡献.

关键词：稀土硼酸盐第一性原理双折射率

The Infiuence of Velocity-dependent Correction Factor on Proton Decay Reactions in Massive White Dwarfs

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Research in Astronomy and Astrophysics 2024年第3期24卷 169-179页

作者： jing-jing liu Dong-Mei liu College of Science Hainan Tropical Ocean UniversitySanya 572022China

Twenty-five typical massive white dwarfs(WDs)are selected and the proton decay reaction catalyzed by magnetic monopoles(MMs)for these WDs is discussed.A velocity-dependent correction factor strongly affects the *** find that a strong suppression controls the monopole catalysis of nucleon decay by the correction *** maximum number of MMs is captured and the luminosity can be 2.235×10^(21)and 1.7859×10^(32)erg s^(-1)(e.g.,for the O+Ne core mass WD J055631.17+130639.78).The luminosities of most massive WDs agree well with the observations at relatively low temperatures(e.g.,T_(6)=0.1),but can be three and two orders of magnitude higher than those of the observations for model(Ⅰ)and(Ⅱ)at relatively high temperatures(e.g.,T_(6)=10),*** luminosities of model(Ⅰ)are about one order of magnitude higher than those of model(Ⅱ).Since we consider the effect of the number of MMs captured on the mass–radius relation and the suppression of the proton decay by the correction factor,the study by model(Ⅱ)may be an improved estimation.

关键词： astroparticle physics-nuclear reactions-nucleosynthesis-abundances-(stars) white dwarfs

Iron group nuclei electron capture in super-Chandrasekhar superstrong magnetic white dwarfs

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Research in Astronomy and Astrophysics 2021年第11期21卷 153-164页

作者： jing-jing liu Dong-Mei liu College of Science Hainan Tropical Ocean UniversitySanya 572022China

Using the theory of relativistic mean-field effective interactions,the influences of superstrong magnetic fields(SMFs)on electron Fermi energy,binding energy per nucleus and single-particle level structure are discussed in super-Chandrasekhar magnetic white *** on the relativistical SMFs theory model of Potekhin et al.,the electron chemical potential is corrected in SMFs,and the electron capture(EC)of iron group nuclei is investigated by using the Shell-Model Monte Carlo method and Random Phase Approximation *** EC rates can increase by more than three orders of magnitude due to the increase of the electron Fermi energy and the change of single-particle level structure by ***,the EC rates can decrease by more than four orders of magnitude due to increase of the nuclei binding energy by *** compare our results with those of FFNs(Fuller et al.),AUFDs(Aufderheide et al.)and Nabi(Nabi et al.).Our rates are higher by about four orders of magnitude than those of FFN,AUFD and Nabi due to *** study may have important reference value for subsequent studies of the instability,mass radius relationship,and thermal and magnetic evolution of super-Chandrasekhar magnetic white dwarfs.

关键词： nuclear reactions,nucleosynthesis,abundances stars:white dwarfs

新疆南天山榆树沟含石榴夕线石泥质麻粒岩的超高温变质作用及其构造意义

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岩石学报 2025年第1期41卷 215-236页

作者：荆彦清仝来喜刘兆李超大陆动力学国家重点实验室西北大学地质学系西安710069

天山造山带是中亚造山带的重要组成部分,新疆南天山造山带出露有橄榄岩-麻粒岩地体,其北部榆树沟地区麻粒岩超高温变质作用的确定及P-T-t轨迹的建立为南天山造山带增生造山过程的研究提供了重要依据。本文主要以榆树沟地区3个含石榴夕... 详细信息

天山造山带是中亚造山带的重要组成部分,新疆南天山造山带出露有橄榄岩-麻粒岩地体,其北部榆树沟地区麻粒岩超高温变质作用的确定及P-T-t轨迹的建立为南天山造山带增生造山过程的研究提供了重要依据。本文主要以榆树沟地区3个含石榴夕线石泥质麻粒岩为研究对象,在详细岩相学研究的基础上进行了温压计算、相平衡模拟及锆石U-Pb年龄分析。结果显示其普遍保留了4个阶段的矿物组合:(1)峰前阶段(M1)主要是石榴子石核部与核部包裹体矿物Grt1+Bt1+Pl1+Ilm1+Rt1+Qz1±Ksp1;(2)峰期阶段(M2)由石榴子石幔部和基质矿物核部组成,Grt2+Sil2+Ksp2+Pl2+Ilm2+Rt2+Qz2+Liq2,其温压条件为910~973℃和0.90~1.09GPa;(3)高压麻粒岩相阶段(M3)主要是石榴子石内边部和边部包裹体及基质中矿物的边部,Grt3+Bt3+Sil3+Ksp3+Pl3+Ilm3+Rt3+Qz3+Liq3,其温压结果为845~869℃和1.01~1.14GPa;(4)角闪岩相退变质阶段(M4)以石榴子石的外边部及围绕石榴子石的矿物为代表,Grt4+Bt4+Sil4+Ksp4+Pl4+Ilm4+Qz4±Rt4,其温压条件为701~737℃和0.7~0.8GPa。温压结果指示泥质麻粒岩记录了一条逆时针P-T轨迹。锆石U-Pb年龄分析结果指示原岩沉积是在427Ma之后,超高温变质作用发生在397~409Ma,压力峰期变质作用年龄范围为381~395Ma,退变质年龄结果为355~387Ma。超高温变质作用的热源可能是泥盆纪弧岩浆侵入,随后麻粒岩及与之接触的橄榄岩被俯冲板片捕获并经历了高压变质作用,后期受挤压折返发生了退变质降压冷却。

关键词：泥质麻粒岩超高温变质作用 P-T轨迹榆树沟南天山

Integrating deep learning and logging data analytics for lithofacies classification and 3D modeling of tight sandstone reservoirs

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Geoscience Frontiers 2022年第1期13卷 350-363页

作者： jing-jing liu Jian-Chao liu School of Earth Science and Resources Chang’an UniversityXi’an 710064China

The lithofacies classification is essential for oil and gas reservoir exploration and *** traditional method of lithofacies classification is based on"core calibration logging"and the experience of *** approach has strong subjectivity,low efficiency,and high *** uncertainty may be one of the key factors affecting the results of 3 D modeling of tight sandstone *** recent years,deep learning,which is a cutting-edge artificial intelligence technology,has attracted attention from various ***,the study of deep-learning techniques in the field of lithofacies classification has not been ***,this paper proposes a novel hybrid deep-learning model based on the efficient data feature-extraction ability of convolutional neural networks(CNN)and the excellent ability to describe time-dependent features of long short-term memory networks(LSTM)to conduct lithological facies-classification *** results of a series of experiments show that the hybrid CNN-LSTM model had an average accuracy of 87.3%and the best classification effect compared to the CNN,LSTM or the three commonly used machine learning models(Support vector machine,random forest,and gradient boosting decision tree).In addition,the borderline synthetic minority oversampling technique(BSMOTE)is introduced to address the class-imbalance issue of raw *** results show that processed data balance can significantly improve the accuracy of lithofacies *** that,based on the fine lithofacies constraints,the sequential indicator simulation method is used to establish a three-dimensional lithofacies model,which completes the fine description of the spatial distribution of tight sandstone reservoirs in the study *** to this comprehensive analysis,the proposed CNN-LSTM model,which eliminates class imbalance,can be effectively applied to lithofacies classification,and is expected to improve the reality of the geologic

关键词： Deep learning Convolutional neural networks LSTM Lithological-facies classification 3D modeling Class imbalance

Comparation of Activity against Aβ Aggregation between RR and LPFFD

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Chinese Journal of Polymer Science 2015年第7期33卷 1009-1017页

作者： jing liu 袁直 Key Laboratory of Functional Polymer Materials of Ministry of Education and Institute of Polymer Chemistry Nankai University and Collaborative Innovation Center of Chemical Science and Engineering

Here, we introduce the design of the structure of RR（RyyAAFFARR）, an inhibitor of Aβ aggregation, using molecular docking, and compare the inhibitory ability between RR and LPFFD, which interacts with Aβ mainly depending on hydrophobic interaction. Our results showed that RR which can target multiple regions of Aβ with multiple weak interactions is better than those that only target a single region with the single driving force mainly.

关键词： Molecular docking Multiple weak interactions Affinity Inhibitory ability

Synergistic effects of Nb and Mo on hydrogen-induced cracking of pipeline steels:A combined experimental and numerical study

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Journal of Materials Science & Technology 2023年第27期158卷 156-170页

作者： Shiqi Zhang Luming Qi Shilong liu Zhixian Peng y.Frank Cheng Feng Huang jing liu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Institute of Advanced Steels and Materials School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Department of Mechanical Engineering University of CalgaryCalgaryAB T2N 1N4Canada Hubei Engineering Technology Research Centre of Marine Materials and Service Safety Wuhan University of Science and TechnologyWuhan 430081China

The synergistic effects of Nb and Mo on hydrogen-induced cracking(HIC)of pipeline steels were studied experimentally and *** results showed that Mo was primarily segregated at grain-boundaries(GBs)or solid-dissolved in the matrix,while most Nb and a small amount of Mo formed dis-persed(Nb,Mo)C nano-precipitates and refined the *** with Nb alloying,the multi-ple additions of Nb-Mo played dual roles in affecting H diffusion:primarily,the H-traps densities such as GBs,precipitates,and solute Mo atoms increased,providing an advantage;however,Mo slightly reduced the H-trapping capacity of precipitates,playing an adverse ***,the beneficial effects far outweighed the adverse effects,thereby reducing H diffusivity and inhibiting crack ***-ally,Nb and Mo hindered crack propagation synergistically as follows:(i)Mo enhanced GB cohesion by repelling H,impeding intergranular cracking and hydrogen-enhanced decohesion(HEDE);(ii)Nb reduced the proportion of3/high-angle grain boundaries,increasing cracking resistance;(iii)(Nb,Mo)C precip-itates impeded H-dislocation interactions,reducing the hydrogen-enhanced localized plasticity(HELP).

关键词： Hydrogen-induced cracking Nb-Mo microalloying Hydrogen permeation Precipitate Pipeline steel