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Late Permian to Triassic intraplate orogeny of the southern Tianshan and adjacent regions, NW China

Geoscience Frontiers 2014年第1期5卷 83-93页

作者： Wei ju Guiting Hou School of Earth and Space Science Peking University The Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of Education

The South Tianshan Orogen and adjacent regions of Central Asia are located in the southwestern part of the Central Asian Orogenic Belt. The formation of South Tianshan Orogen was a diachronous, scissors-like process, which took place during the Palaeozoic, and its western segment was accepted as a site of the final collision between the Tarim Craton and the North Asian continent, which occurred in the late Palaeozoic. However, the post-collisional tectonic evolution of the South Tianshan Orogen and adjacent regions remains debatable. Based on previous studies and recent geochronogical data, we suggest that the final collision between the Tarim Craton and the North Asian continent occurred during the late Carboniferous. Therefore, the Permian was a period of intracontinental environment in the southern Tianshan and adjacent regions. We propose that an earlier, small-scale intraplate orogenic stage occurred in late Permian to Triassic time, which was the first intraplate process in the South Tianshan Orogen and adjacent regions. The later large- scale and well-known Neogene to Quaternary intraplate orogeny was induced by the collision between the India subcontinent and the Eurasian plate. The paper presents a new evolutionary model for the South Tianshan Orogen and adjacent regions, which includes seven stages：（I） late Ordovician-early Silurian opening of the South Tianshan Ocean; （11） middle Silurian-middle Devonian subduction of the South Tianshan Ocean beneath an active margin of the North Asian continent; （111） late Devonian-late Carboniferous closure of the South Tianshan Ocean and collision between the Kazakhstan-Yili and Tarirn continental blocks; （IV） early Permian post-collisional magmatism and rifting; （V） late Permian-Triassic the first intraplate orogeny; （Vt） jurassic-Palaeogene tectonic stagnation and （VII） Neocene-Quaternary intraplate orogeny.

关键词： Central Asian Orogenic Belt Northern Xinjiang South Tianshan Ocean Tectonics Tarim-North Asia collision

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A Novel Carbon Nanotube-Supported NiP Amorphous Alloy Catalyst and Its Hydrogenation Activity

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Journal of Natural Gas Chemistry 2006年第4期15卷 313-318页

作者： Yan ju Fengyi Li Department of Chemistry Nanchang University Nanchang 330031 Jiangxi China

A carbon nanotube-supported NiP amorphous catalyst （NiP/CNT） was prepared by induced reduction. Benzene hydrogenation was used as a probe reaction for the study of catalytic activity. The effects of the support on the activity and thermal stability of the supported catalyst were discussed based on various characterizations, including XRD, TEM, ICP, XPS, H2-TPD, and DTA. In comparison with the NiP amorphous alloy, the benzene conversion on NiP/CNT catalyst was lower, but the specific activity of NiP/CNT was higher, which is attributed to the dispersion produced by the support, an electron-donating effect, and the hydrogen-storage ability of CNT. The NiP/CNT thermal stability was improved because of the dispersion and electronic effects and the good heat-conduction ability of the CNT support.

关键词： carbon nanotube catalyst support catalytic property Ni P hydrogenation benzene

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The Expansion of a Wedge of Gas into Vacuum with Small Angle in Two-Dimensional Isothermal Flow

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Chinese Annals of Mathematics,Series B 2016年第3期37卷 395-404页

作者： ju GE Wancheng SHENG Department of Mathematics Shanghai University Shanghai 200444 China Department of Mathematics China University of Petroleum Qingdao 266555 Shandong China

In this paper, the authors consider the expansion problem of a wedge of gas into vacuum for the two-dimensional Euler equations in isothermal flow. By the bootstrapping argument, they prove the global existence of the smooth solution through the direct method in the case 0 〈 θ 〈 -θ=arctan 1/（√2＋√5）, where θ is the half angle of the wedge. Furthermore, they get the uniform C^1,1 estimates of the solution to the expansion problem.

关键词： Hyperbolic partial differential equation 2D Riemann problem Rarefaction wave Isothermal flow

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Boron-10 stimulated helium production and accelerated radiation displacements for rapid development of fusion structural materials

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Journal of Materiomics 2024年第2期10卷 377-385页

作者： Yunsong jung ju Li Department of Nuclear Science and Engineering and Department of Materials Science and Engineering Massachusetts Institute of TechnologyCambridgeMA02139USA Korea Institute of Fusion Energy Daejeon34133Republic of Korea

Boron doping,combined with neutron capture in fission reactors,has been used to simulate the helium effect on fusion structural ***,inhomogeneous helium bubble formation was often observed due to boron segregation to grain *** excess radiation displacements due to^(10)B(n,α)^(7)Li reaction,the high-energy lithium and helium ions,also were not accounted for,which can significantly accelerate the displacements-per-atom(dpa)accumulation alongside helium production(appm).Hereby an isotopically pure^(10)B doping approach is proposed to simulate the extreme envi-ronment inside fusion reactors with a high He appm-to-dpa ratio of about 10,which is about 10^(2)×larger than in fission *** modeling showed that~13%of total radiation displacement was induced by^(10)B(n,α)^(7)Li in the case of 1000 appm^(10)B doped Fe samples,which becomes even greater with increasing^(10)B *** homogenous radiation damage and helium generation are pre-dicted for grain sizes less than 1 mm,even if the boron partially formed precipitates or segregates on grain *** studies with various^(10)B doping(and^(235)U-codoping)levels in research reactors showed the estimated helium generation and radiation damage would significantly mimic fusion conditions and greatly expedite fusion materials testing,from many years down to months.

关键词： Fusion power reactor Helium transmutation He appm-to-dpa ratio Boron-10 doping Accelerated materials testing

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Climatology of the Meteorological Factors Associated with Haze Events over Northern China and Their Potential Response to the Quasi-Biannual Oscillation

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Journal of Meteorological Research 2017年第5期31卷 852-864页

作者： ju LIANG Yaoguo TANG Department of Meteorology University of Reading Nanjing University of Information Science & Technology

An upswing in haze weather during autumn and winter has been observed over North and Northeast China in re- cent years, imposing adverse impacts upon local socioeconomic development and human health. However, such an increase in the occurrence of haze events and its association with natural climate variability and climate change are not well understood. To investigate the climatology of the meteorological factors associated with haze events and their natural variability, this study uses a meteorological pollution index called PLAM （Parameter Linking Air-qual- ity to Meteorological conditions） and ERA-Interim reanalysis data. The results suggest that high PLAM values tend to occur over southern parts of northem China, implying the weather conditions over this area are favorable for the occurrence of haze weather. For the period 1979-2014, the regional mean PLAM shows an overall increase across Beijing, Tianjin, and Hebei Province, and parts of Shanxi Province. Also, a periodicity of 28-34 months is found in the temporal variation of PLAM, which implies a potential association of PLAM with the stratospheric Quasi-Bian- nual Oscillation （QBO）. By using the QBO index during the autumn and winter seasons in the preceding year, an in- crease in PLAM is found for the westerly phases of the QBO, relative to the easterly phases. An upper-tropospheric warming is also found in the westerly phases, which can induce a stable stratification that favors the increase in PLAM across the midlatitudes. The modulations of large-scale environmental factors, including moist static stability, vertical velocity, and temperattu＇e advection, also act to enhance PLAM in the westerly phases. However, the baro- clinic term of moist potential vorticity at 700 hPa tends to decrease over the south, and an increase in low-level as- cent is found over the north. These factors can reduce PLAM and possibly limit the statistical significance of the in- creased PLAM in the westerly phases of the QBO.

关键词： haze events Parameter Linking Air-quality to Meteorological conditions (PLAM) Quasi-Biannual Os-cillation (QBO)

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Role of the Λ(1600) in the K^-p→Λπ^0π^0 reaction

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Communications in Theoretical Physics 2020年第4期72卷 64-70页

作者： He Zhou ju-jun Xie Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBejing 101408China School of Physics and Microelectronics Zhengzhou UniversityZhengzhouHenan 450001China

Role of theΛ(1600)is studied in the K^-p→Λπ^0π^0 reaction by using the effective Lagrangian approach near the *** perform a calculation for the total and differential cross sections by considering the contributions from theΛ(1600)andΛ(1670)intermediate resonances decaying intoπ^0∑^*0(1385)with∑^*0(1385)decaying intoπ^0Λ.Additionally,the non-resonance process from u-channel nucleon pole is also taken into *** our model parameters,the current experimental data on the total cross sections of the K^-p→Λπ^0π^0 reaction can be well *** is shown that we really need the contribution from the A(1600)with spin-parity J^P=1/2^+,and that these measurements can be used to determine some of the properties of theΛ(1600)***,we also plot theπ0Λinvariant mass distributions which could be tested by the future experimental measurements.

关键词： KN scattering effective Lagrangian approach hyperon resonance

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A Subclass of Ockham Algebras

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Acta Mathematica Sinica,English Series 2012年第10期28卷 2115-2128页

作者： Jie FANG Zhong ju SUN School of Computer Science Guangdong Polytechnic Normal University

Here we introduce a subclass of the class of Ockham algebras （L; f） for which L satisfies the property that for every x ∈ L, there exists n 〉 0 such that fn（x） and f^n＋1（x） are complementary. We characterize the structure of the lattice of congruences on such an algebra （L; f）. We show that the lattice of compact congruences on L is a dual Stone lattice, and in particular, that the lattice Con L of congruences on L is boolean if and only if L is finite boolean. We also show that L is congruence coherent if and only if it is boolean. Finally, we give a sufficient and necessary condition to have the subdirectly irreducible chains.

关键词： Boolean algebra Ockham algebra congruence congruence coherence subdirectly irre-ducible

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弹性网络正则化的高维序列因果关联识别研究

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华北理工大学学报（自然科学版） 2025年第1期47卷 96-105页

作者：张居营安风楼河北金融学院金融与投资学院河北保定071051 太平洋证券股份有限公司北京100033

弹性网络正则化方法兼顾了L1正则化与L2正则化的优点,能够解决高维时间序列因果关系分析中共线性、过度拟合与信息冗余等问题,有效发掘高维序列之间的主要关联关系。首先,基于VAR模型与长期格兰杰因果关联网络,阐述高维序列因果关联识... 详细信息

弹性网络正则化方法兼顾了L1正则化与L2正则化的优点,能够解决高维时间序列因果关系分析中共线性、过度拟合与信息冗余等问题,有效发掘高维序列之间的主要关联关系。首先,基于VAR模型与长期格兰杰因果关联网络,阐述高维序列因果关联识别的方法;其次,讨论了弹性网络正则化如何解决高维序列因果关系建模的弊端,融合L1与L2正则化的主要特点;最后,结合多维大宗商品期货价格日度波动率序列,探索了弹性网络正则化在高维序列因果关联识别的应用,并与其他正则化方法进行比较。结果表明,弹性网络正则化方法避免了信息冗余与“过度稀疏化”的问题,识别与提炼商品价格波动因果关联网络中的主要影响节点与传导关系,挖掘序列关系网络中的主要因果关联。

关键词：弹性网络正则化高维序列长期格兰杰因果关联网络

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Elastic Low-Energy Electron Collisions with Methanethiol

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Ke-dong Wang ju Meng Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic Chemistry of MOE School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 ChinaSchool of Physics and Electronical Engineering Henan Normal University Xinxiang 453007 China School of Physics and Electronical Engineering Henan Normal University Xinxiang 453007 China

We report ab initio scattering calculations results of electron-methanethiol collisions using R-matrix approach within the static-exchange and static-exchange-polarization approximations. The calculated elastic integral cross sections are in agreement with the experimental data. Two shape resonances of 2A′ symmetry located at 4.06 and 8.32 eV are detected within static-exchange-polarization model. For this dipole molecule, Born-closure procedure was used to account for the higher partial waves (l>4) for the convergence of the cross section. The effective collision frequencies over a wide electron temperature range (200–30000 K) are calculated using the data of the momentum-transfer cross section.

关键词： Elastic integral cross sections Differential cross section Shape resonance

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Advances in Research on Anticancer Properties of Salidroside

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Chinese Journal of Integrative Medicine 2021年第2期27卷 153-160页

作者： SUN An-qi ju Xiu-lian Key Laboratory for Green Chemical Process of Ministry of Education School of Chemical Engineering&PharmacyWuhan Institute of TechnologyWuhan(430073)China The College of Post and Telecommunication Wuhan Institute of TechnologyWuhan(430073)China

Salidroside is a phenolic secondary metabolite present in plants of the genus Rhodiola,and studies investigating its extensive pharmacological activities and mechanisms have recently attracted increasing *** review summarizes the progress of recent research on the antiproliferative activities of salidroside and its effects on breast,ovarian,cervical,colorectal,lung,liver,gastric,bladder,renal,and skin cancer as well as gliomas and ***,it provides a reference for the further development and utilization of salidroside.

关键词： salidroside anticancer mechanism antiproliferative Chinese medicine review

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