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Petrology,Metamorphic P-T Paths and Zircon U-Pb Ages for Paleoproterozoic Mafic Granulites from Xuanhua,North China Craton

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Journal of Earth Science 2019年第6期30卷 1197-1214页

作者： guidong wei Fanmei Kong Hao Liu Xiaoman Wang Yancheng Zhang Xiaohan Liu Shandong Key Laboratory of Depositional Mineralization and Sedimentary Minerals Shandong University of Science and Technology

The studied mafic granulites are located at Xiwangshan,Xuanhua region in the north of the Trans-North China Orogen(TNCO),occurring as lens within tonalite-trondhjemite-granodiorite(TTG)gneisses in the eastern part of the Xiwangshan *** rocks contain the representative granulite-facies minerals such as garnet,clinopyroxene,orthopyroxene,plagioclase,amphibolite,rutile and quartz,and also well-developed melt pseudomorph and *** the prograde metamorphic stage(M1)cannot be retrieved due to rare preservation of pre-peak-stage mineral associations,three distinct mineral assemblages that formed in different metamorphic stages can be identified,based on petrography and mineralogy *** peak stage(M2)is characterized by Grt2+Cpx2+Amp2+Pl2+Rt+melt pseudomorphs,and a post-peak decompression stage(M3)contains a mineral assemblage of Grt3+Opx3+Cpx3+Amp3+Pl3,while a later-retrogression stage(M4)is featured by coronas of Amp4+Pl4 surrounding *** calculating metamorphic P-T conditions using THERMOCALC,stage M2 was constrained to be 13.2–14.8 kbar and 1050–1080℃,and M3 recorded P-T conditions of 5.7–7.3 kbar and 825–875℃,while M4 yielded P of^5 kbar and T of^660℃,consistent with amphibolite facies *** into account of all these petrological data,we propose that the mafic granulite experienced a high-pressure(HP)and ultra-high temperature(UHT)granulite-facies metamorphism during the peak metamorphism,which was accompanied with a clockwise P-T path.U-Pb dating of metamorphic zircons in the granulites yields two groups of ages at 1853±14 and 1744±44 Ma,*** suggest that the older age corresponded to the HP-UHT metamorphism,while the younger age represented an retrograde metamorphic event during cooling.

关键词： ultrahigh-temperature metamorphism phase equilibrium modeling mafic granulite Trans-North China Orogen North China Craton

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山东昌乐新生代碱性玄武岩与地幔捕虏体中各类单斜辉石的地球化学特征及其意义

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地球科学 2019年第4期44卷 1169-1188页

作者：刘晓寒孔凡梅李旭平魏贵东刘浩王笑贺振鹏山东科技大学地球科学与工程学院山东青岛266590

山东昌乐位于华北克拉通东部,郯庐断裂带中段,广泛出露挟裹幔源捕虏体的新生代碱性玄武岩.为深入了解华北克拉通演化,依据岩相学特征、矿物化学成分特征,把昌乐碱性玄武岩中单斜辉石主要分为三大类:第1类为幔源捕虏体中原生单斜辉石,其... 详细信息

山东昌乐位于华北克拉通东部,郯庐断裂带中段,广泛出露挟裹幔源捕虏体的新生代碱性玄武岩.为深入了解华北克拉通演化,依据岩相学特征、矿物化学成分特征,把昌乐碱性玄武岩中单斜辉石主要分为三大类:第1类为幔源捕虏体中原生单斜辉石,其主、微量元素含量呈现趋势不一致的解耦现象,且LREE、HREE各异特征表明其经历了多期、不同程度的地幔富集交代和部分熔融作用(低于10%的尖晶石相部分熔融),交代熔体包括地幔富碱(K)富Al硅酸盐熔/流体,可能有碳酸盐熔体的贡献;第2类为幔源捕虏体中筛状单斜辉石,是部分熔融和熔体交代作用的共同产物,从无筛孔部位到筛孔周围远离筛孔部位和紧挨着筛孔部位,呈现出受熔体作用逐渐加强趋势,离筛孔较远部位记录了玄武质熔浆作用之前的一次富碱(K)富Al熔体交代的特征,而紧挨着筛孔的部位受晚期玄武质熔浆作用的影响最强;第3类为幔源捕虏体中反应边单斜辉石及玄武岩中斑晶单斜辉石,两者的化学成分及形成条件相似,显示HFSE正异常,LILE负异常,受OIB特征寄主玄武岩浆强烈的影响.昌乐新生代碱性玄武岩地幔捕虏体中单斜辉石显示经历多期"熔体作用"和不同程度的部分熔融特征,是研究区岩石圈地幔不均一性的体现.

关键词：新生代碱性玄武岩单斜辉石幔源捕虏体地球化学

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Reliability and control of strongly nonlinear vibro-impact system under external and parametric Gaussian noises

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Science China(Technological Sciences) 2020年第9期63卷 1837-1845页

作者： LIU Li XU wei YANG guidong HUANG DongMei Department of Applied Mathematics Northwestern Polytechnic UniversityXi’an710072China School of Mathematics and Statistics Ningxia UniversityYinchuan750021China School of Mathematics and Statistics Xidian UniversityXi’an710071China

This paper mainly focuses on reliability and the optimal bounded control for maximizing system reliability of a strongly nonlinear vibro-impact system. Firstly, the new stochastic averaging in which the impact condition is converted to the system energy is applied to obtain the averaged It? stochastic differential equation, by which the associated Backward Kolmogorov(BK)equation and Generalized Pontryagin(GP) equation are derived. Then, the dynamical programming equations are obtained based on the dynamical programming principle, by which the optimal bounded control for maximizing system reliability is ***, the effects of the bounded control and noise intensity on the reliability of the vibro-impact system are discussed in detail;meanwhile, the influence of impact conditions on the system's reliability is also studied. The feasibility and effectiveness of the proposed analytical method are substantiated by numerical results obtained from Monte-Carlo simulation.

关键词： vibro-impact system first-passage failure stochastic averaging method stochastic optimal control

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Analytical and NumericalMethods to Study the MFPT and SR of a Stochastic Tumor-Immune Model

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2177-2199页

作者： Ying Zhang wei Li guidong Yang Snezana Kirin School of Mathematics and Statistics Xidian UniversityXi’an710071China Innovation Center of Faculty of Mechanical Engineering Belgrade11100Serbia

The Mean First-Passage Time (MFPT) and Stochastic Resonance (SR) of a stochastic tumor-immune model withnoise perturbation are discussed in this paper. Firstly, considering environmental perturbation, Gaussian whitenoise and Gaussian colored noise are introduced into a tumor growth model under immune surveillance. Asfollows, the long-time evolution of the tumor characterized by the Stationary Probability Density (SPD) and MFPTis obtained in theory on the basis of the Approximated Fokker-Planck Equation (AFPE). Herein the recurrenceof the tumor from the extinction state to the tumor-present state is more concerned in this paper. A moreefficient algorithmof Back-Propagation Neural Network (BPNN) is utilized in order to testify the correction of thetheoretical *** the existence of aweak signal, the functional relationship between Signal-to-NoiseRatio (SNR), noise intensities and correlation time is also studied. Numerical results show that both multiplicativeGaussian colored noise and additive Gaussian white noise can promote the extinction of the tumors, and themultiplicative Gaussian colored noise can lead to the resonance-like peak on MFPT curves, while the increasingintensity of the additiveGaussian white noise results in theminimum of MFPT. In addition, the correlation timesare negatively correlated with MFPT. As for the SNR, we find the intensities of both the Gaussian white noise andthe Gaussian colored noise, as well as their correlation intensity can induce SR. Especially, SNR is monotonouslyincreased in the case ofGaussian white noisewith the change of the correlation *** last, the optimal parametersin BPNN structure are analyzed for MFPT from three aspects: the penalty factors, the number of neural networklayers and the number of nodes in each layer.

关键词： Stochastic tumor-immune model mean first-passage time stochastic resonance signal-to-noise ratio back-propagation neural network

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Bifurcation Analysis of a Nonlinear Vibro-Impact System with an Uncertain Parameter via OPA Method

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Computer Modeling in Engineering & Sciences 2024年第1期138卷 509-524页

作者： Dongmei Huang Dang Hong wei Li guidong Yang Vesna Rajic School of Mathematics and Statistics Xidian UniversityXi’an710071China Department of Mathematics Changzhi UniversityChangzhi046011China Department for Statistics and Mathematics Faculty of EconomicsUniversity of BelgradeBelgrade11000Serbia

In this paper,the bifurcation properties of the vibro-impact systems with an uncertain parameter under the impulse and harmonic excitations are ***,by means of the orthogonal polynomial approximation(OPA)method,the nonlinear damping and stiffness are expanded into the linear combination of the state *** condition for the appearance of the vibro-impact phenomenon is to be transformed based on the calculation of themean ***,the stochastic vibro-impact systemcan be turned into an equivalent high-dimensional deterministic non-smooth *** different Poincarésections are chosen to analyze the bifurcation properties and the impact numbers are identified for the periodic ***,the numerical results verify the effectiveness of the approximation method for analyzing the considered nonlinear ***,the bifurcation properties of the system with an uncertain parameter are explored through the high-dimensional deterministic *** can be found that the excitation frequency can induce period-doubling bifurcation and grazing *** the randomintensitymay result in a diffusion-based trajectory and the impact with the constraint plane,which induces the topological behavior of the non-smooth system to change *** is also found that grazing bifurcation appears in advance with increasing of the random *** stronger impulse force can result in the appearance of the diffusion phenomenon.

关键词： Orthogonal polynomial approximation vibro-impact systems non-smooth systems grazing bifurcation

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华北中部造山带西望山超高温基性麻粒岩的变质演化

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山东科技大学学报（自然科学版） 2020年第2期39卷 24-35页

作者：魏贵东孔凡梅李旭平 JüRGEN Reinhardt 刘晓寒张艳成王晓曼山东科技大学地球科学与工程学院山东青岛266590 西开普大学地球科学系南非贝尔维尔7535

华北中部造山带西望山地区基性麻粒岩的变质演化过程研究有助于揭示华北中部带前寒武纪变质基底的形成与演化历史。基于对宣化西望山地区基性麻粒岩的详细岩相学观察与矿物化学分析,识别出3期变质演化阶段:早期进变质阶段(M1)矿物组合... 详细信息

华北中部造山带西望山地区基性麻粒岩的变质演化过程研究有助于揭示华北中部带前寒武纪变质基底的形成与演化历史。基于对宣化西望山地区基性麻粒岩的详细岩相学观察与矿物化学分析,识别出3期变质演化阶段:早期进变质阶段(M1)矿物组合为石榴石+单斜辉石+斜长石+金红石+石英;峰期变质阶段(M2)矿物组合为石榴石+单斜辉石+斜长石+角闪石+钛铁矿+熔体;晚期降压阶段(M3)矿物组合为石榴石+单斜辉石+角闪石+斜长石+钛铁矿+磁铁矿。对基性麻粒岩的相平衡模拟研究表明,峰期变质阶段(M2)的温压条件为940~1000℃,12.4~14 kbar;峰期后降压阶段的温压条件为660~760℃,5~6.2 kbar;构成一条降压冷却的顺时针P-T轨迹。本次研究表明西望山基性麻粒岩经历了高压-超高温变质作用。

关键词：基性麻粒岩超高温变质作用相平衡模拟华北中部造山带

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Tianwen-1 Mars entry vehicle trajectory and atmosphere reconstruction preliminary analysis

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Astrodynamics 2022年第1期6卷 81-91页

作者： Haogong wei wei Rao Guangqiang Chen guidong Wang Xin Zou Qi Li Yanqi Hu Beijing Institute of Spacecraft System Engineering Beijing 100094China China Academy of Aerospace Aerodynamics Beijing 100074China

The Tianwen-1 Mars entry vehicle successfully landed on the surface of Mars in southern Utopia Planitia on May 15,2021,at 7:18(UTC+8).To acquire valuable Martian flight data,a scientific instrumentation package consisting of a flush air data system and a multilayer temperature-sensing system was installed aboard the entry vehicle.A combined approach was applied in the entry,descent,and landing trajectory reconstruction using all available data obtained by the inertial measurement unit and the flush air data *** aerodynamic database covering the entire flight regime was generated using computational fluid dynamics methods to assist in the reconstruction process.A preliminary analysis of the trajectory reconstruction result,along with the atmosphere reconstruction and aerodynamic performance,was *** results show that the trajectory agrees closely with the nominal trajectory and the wind-relative *** wind occurred at the end of the trajectory.

关键词： Tianwen-1 flush air data system(FADS) trajectory reconstruction Martian atmosphere aerodynamics

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Poly(heptazine imide)nanocrystal for hydrogen peroxide evolution in the dark by accumulating photo-generated electrons

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Nano Research 2024年第9期17卷 8036-8044页

作者： Song Kou Shu Lian Xiaodong Xie wei Ren Yu Jin Jiahui Bao Honghui Ou guidong Yang XJTU-Oxford International Joint Laboratory for Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China Fujian-Taiwan-Hongkong-Macao Science and Technology Cooperation Base of Intelligent Pharmaceutics Institute of OceanographyCollege of Materials and Chemical EngineeringMinjiang UniversityFuzhou 350108China School of Food and Bioengineering Fujian Polytechnic Normal UniversityFuqing 350300China

Organic conjugated polymers have received extensive attention due to their unique electronic ***,there have been relatively few reports on the dark photocatalytic reactions utilizing organic conjugated ***,we report the successful synthesis of an organic conjugated polymer based on poly(heptazine imide)nanocrystals(CNNCs)for H_(2)O_(2)evolution and biomedical applications using a simple salt molten method and sonication-centrifugation *** results show that these colloid CNNCs have the characteristics of photogenerated electrons accumulation and realize dark photocatalysis with high reducibility under visible light ***,these accumulating photogenerated electrons can reduce O_(2)in darkness to produce H_(2)O_(2).In addition,cytotoxicity tests were conducted and it was found that H_(2)O_(2)produced under dark conditions could oxidize L-arginine(L-Arg)to NO,which effectively killed tumors in the *** work provides an important strategy to construct organic conjugated semiconductor nanocrystals and applying them to future energy and biomedical fields.

关键词： poly(heptazine imide) photocatalysis photogenerated electrons hydrogen peroxide evolution cancer treatment

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西藏南部日喀则蛇绿岩中角闪岩的Sr-Nd同位素地球化学研究

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山东科技大学学报（自然科学版） 2020年第2期39卷 1-11页

作者：张艳成李旭平麻少婷杜龙王晓曼孔凡梅魏贵东张书凯 SCHERTL Hans-Peter 山东科技大学地球科学与工程学院山东青岛266590 波鸿鲁尔大学地球科学学院地质矿产地球物理研究所德国波鸿44780

藏南雅江带中段蛇绿岩中产出的角闪岩是支撑蛇绿岩侵位的变质底板。追溯其源区特征有助于深刻解译雅江带蛇绿岩侵位过程。对雅江带中段日喀则白朗蛇绿岩中包裹的石榴石单斜辉石角闪岩与单斜辉石角闪岩地球化学特征进行了系统研究,并将... 详细信息

藏南雅江带中段蛇绿岩中产出的角闪岩是支撑蛇绿岩侵位的变质底板。追溯其源区特征有助于深刻解译雅江带蛇绿岩侵位过程。对雅江带中段日喀则白朗蛇绿岩中包裹的石榴石单斜辉石角闪岩与单斜辉石角闪岩地球化学特征进行了系统研究,并将其与邻区路曲和吉定基性岩进行对比,从而厘定白朗角闪岩的源区性质和形成过程。研究显示,两种角闪岩微量元素配分型式总体与N-MORB类似,但具有K、U、Pb正异常和Nb、Ta、Ti负异常等岛弧玄武岩特征,且其Sr同位素相对正常,N-MORB明显偏移向俯冲带岛弧相关环境。此外,白朗地区两种角闪岩与路曲和吉定基性岩的εNd(t)=+7.95^+11.18,处于印度洋MORB范围内。综合以上地球化学特征认为,虽然两类角闪岩具有典型MORB型源区特征,但均遭受过俯冲带流体的改造。同时,日喀则蛇绿岩代表的特提斯地幔域与印度洋地幔域具有相似的地球化学特征,指示现今印度洋继承了特提斯地幔域特有的地球化学属性。该研究对进一步明确新特提斯洋俯冲特征提供了新的认识。

关键词：西藏日喀则蛇绿岩角闪岩基性岩源区性质 Sr-Nd同位素

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Oxidative C—H alkynylation of 3,6-dihydro-2H-pyrans

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Chinese Chemical Letters 2019年第7期30卷 1432-1434页

作者： Ran Zhao guidong Feng Xiaodong Xin Honghao Guan Jing Hua Renzhong Wan wei Li Lei Liu Department of Pharmaceutical Analysis School of Pharmacy Shandong University of Traditional Chinese Medicine Ji'nan 250355 China College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China School of Chemistry and Chemical Engineering Shandong University Ji'nan 250100 China State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical Sciences of Guangxi Normal University Guilin 541004 China

Current synthesis of α-substituted 3,6-dihydro-2H-pyrans dominantly relies on functional group transformation. Herein, a direct and practical oxidative C -H alkynylation and alkenylation of 3,6-dihydro-2H-pyran skeletons with a range of potassium trifluoroborates is developed. The metal-free process is well tolerated with a wide variety of 3,6-dihydro-2H-pyrans, rapidly providing a library of 2,4-disubstituted 3,6-dihydro-2H-pyrans with diverse patterns of α-functionalities for further diversification and bioactive small molecule identification.

关键词： 3,6-Dihydro-2H-pyrans C-H Functionalization Alkynylation Oxidation Organoborane

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