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Geochemistry and Geochronology of the Causative Intrusion and a New Genetic Model Study of the Yaojialing Polymetallic Skarn Deposit, Tongling District, China

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 1997-2011页

作者： xiong Yanyun ZHOU Taofa FAN Yu CHEN Jing liu jun School of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China Anhui Mineral Resources and Mines Environmental Engineering Research Center Hefei 230009China

The Yaojialing deposit is the first large-scale Zn-Au-Cu polymetallic skarn deposit located in the Shatanjiao ore field of the Tongling area in the Middle-Lower Yangtze *** has distinct metallogenic characteristics and is clearly different from the known skarn Cu-Au deposits in the Tongling area and the Middle-Lower Yangtze *** studies of the Yaojialing deposit have included rock geochemistry,alteration and mineralization characteristics,as well as metallogenesis and metallogenic ***,there are still numerous problems concerning the coexistence of multiple elements,metallogenetic specialization of the magma and the metallogenic *** this study,using the latest production exploration work on the deposit,we investigated the Yaojialing deposit including its geological characteristics,petrography,LA-ICP MS zircon U-Pb dating and whole rock *** kinds of magmatic rocks have been distinguished for the first time in the deposit,amongst which the granodiorite porphyry exposed on the surface of the mining area,which is the host rock of the veined lead-zinc ore body,is the wall-rock intrusion;and the deep concealed quartz monzonite porphyry is the causative intrusion,the distribution of orebodies and wall-rock alteration characteristics showing regular zoning around the quartz monzonite ***^(206)Pb/^(238)U weighted average age of the granodiorite porphyry is 140.2±1.0 Ma(MSWD=0.85,n=13)by LA-ICP MS zircon U-Pb dating,while the quartz monzonite porphyry is 138.9±1.2 Ma(MSWD=0.60,n=16),which is consistent with petrographic *** geochemical characteristics show that the quartz monzonite porphyry is a high-K calc-alkaline series peraluminous *** trace element characteristics show that the quartz monzonite porphyry is enriched in LILE such as K,Rb,Sr,Ba and LREE,yet depleted in HFSE such as Nb,Ta,P and *** Yaojialing deposit shows the mineralization characteristics of proximal skarn and distal skarn,having the common

关键词： LA-ICP MS zircon U-Pb dating geochemistry Yaojialing deposit Tongling district

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Properties of copper/graphite/carbon nanotubes composite reinforced by carbon nanotubes

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Rare Metals 2013年第3期32卷 278-283页

作者： Xin-Ying liu xiong-Zhi Xiang Fei Niu Xiao-jun Bai Shenzhen Key Laboratory of Special Functional Materials College of Materials Science and Engineering Shenzhen University

Electroless Cu plating was used for flake G powder and CNTs, Cu-G-CNTs （copper/graphite/carbon nanotubes） composites were manufactured by means of powder metallurgical method. The influences of CNTs on the mechanical properties, conductivity properties, friction, and wear performance of the composite were examined. The results indicate that adding a small amount of CNTs can improve comprehensive property of the composites, especially mechanical property. However, excessive CNT, which is easily winding reunion and grain boundary seg- regation, results in performances degradation.

关键词： Cu/G composite Carbon nanotubes Resistivity Friction and wear resistance

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi liu Yan-Bo Li Qi Zhang jun-Zhao Xiao Yi-Fan Wang Tian-Yu Wei Jia-Wei Jiang Ye Wang Qian Peng Liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Palladium-catalyzed meta-C—H bond iodination of arenes with I2

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Chinese Chemical Letters 2020年第5期31卷 1301-1304页

作者： Min liu Ling-jun Li jun Zhang Hui Xu Hui-xiong Dai Chinese Academy of Sciences Key Laboratory of Receptor Research Shanghai Institute of Materia MedicaShanghai 201203China State Key Laboratory of Natural and Biomimetic Drugs Peking UniversityBeijing 100191China University of Chinese Academy of Sciences Beijing 100049China School of Pharmaceutical Science Shanxi Medical UniversityTaiyuan 030001China

Palladium-catalyzed highly meta-selective C—H iodination of phenylacetic acid,benzylphosphonate and benzylsulfonate scaffolds with molecular I2 is developed using a pyridine-type *** practical ester linkages enable the directing template easily installed and readily *** substrate scope is broad,and alkyl,methoxyl,trifluomethyl,and halo substituents are compatible with this *** transformations of ibuprofen iodide intermediates by Pd-catalyzed C—C and C-heteroatom bond formation illustrate the broad utility of this method.

关键词： Palladium catalysis meta-C-H iodination Pyridine-based template Practical ester linkages Molecular I2

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Nonlinear Out-of-Plane Mechanical Behaviours of Rectangular Woven Composite Flexible Skin Under Uniform Normal Pressure

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Acta Mechanica Solida Sinica 2023年第5期36卷 672-684页

作者： Di Chen jun-Jiang xiong School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China School of Transportation Science and Engineering Beihang UniversityBeijing 102206China

This paper seeks to investigate nonlinear out-of-plane mechanical behaviours of woven composite flexible skin(WCFS)through experimental and theoretical ***,quasi-static experiments are carried out on rectangular WCFSs with different aspect ratios under uniform normal pressure to measure out-of-plane deformation and failure ***,a new three-parameter geometric model is presented to describe 3D geometry of pressurized WCFS,and thus,a nonlinear mechanical model is deduced for depicting the relationship between pressure and out-of-plane *** application of the aforementioned models for experimental results shows that the new models have adequately and logically depicted deformation geometry and nonlinear mechanical characteristics.

关键词： Woven compositeﬂexible skin Nonlinear performance Uniform normal pressure Geometric model Mechanical model Aspect ratio

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基于不确定度量化分析的炸药驱动飞片参数标定与预测方法

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数值计算与计算机应用 2017年第2期38卷 143-154页

作者：王艳莉张树道周海兵熊俊刘国昭北京应用物理与计算数学研究所北京100094

炸药驱动飞片实验作为检验炸药爆轰能力的基准实验,在爆轰领域应用广泛,但由于炸药反应迅速、剧烈、不易测量,能够根据现有信息预测炸药驱动飞片实验效果极为重要.然而由于爆轰系统中不确定参数众多,尤其对于精确描述爆轰驱动过程与做... 详细信息

炸药驱动飞片实验作为检验炸药爆轰能力的基准实验,在爆轰领域应用广泛,但由于炸药反应迅速、剧烈、不易测量,能够根据现有信息预测炸药驱动飞片实验效果极为重要.然而由于爆轰系统中不确定参数众多,尤其对于精确描述爆轰驱动过程与做功能力都至关重要的爆轰产物状态方程不确定参数,需要量化其不确定性,及不确定性对最终计算结果的影响,才能做出有效预测.本文聚焦JWL状态方程参数,从不确定度量化角度出发,综合利用实验数据与现有数值模拟数据,基于贝叶斯思想量化给出其后验分布.并针对炸药LX-17,评估参数不确定度对整体计算结果的影响,利用参数后验分布预测不同长度飞片与炸药的驱动效果,并评估预测结果不确定度.本文不仅描述了不确定性从状态参数到最终爆轰驱动能力的传播规律,还预测了不同条件下炸药驱动飞片的能力,及其不确定度,为分析不确定度在爆轰系统中的传播特征,提出模拟爆轰驱动的高置信度计算方法,降低系统整体不确定度奠定了基础,也为通过数值实验预测未知爆轰实验效果提出新的方法思路.

关键词：爆炸力学 JWL状态方程贝叶斯方法参数标定不确定度量化

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Investigation of methane adsorption on chlorite by grand canonical Monte Carlo simulations

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Petroleum Science 2017年第1期14卷 37-49页

作者： Jian xiong Xiang-jun liu Li-Xi Liang Qun Zeng State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Institute of Chemical Materials Engineering Physical Academy of China

In this paper, the methane adsorption behaviours in slit-like chlorite nanopores were investigated using the grand canonical Monte Carlo simulation method, and the influences of the pore sizes, temperatures, water, and compositions on methane adsorption on chlorite were discussed. Our investigation revealed that the isosteric heat of adsorption of methane in slit-like chlorite nanopores decreased with an increase in pore size and was less than 42 kJ/mol, suggesting that methane adsorbed on chlorite through physical adsorption. The methane excess adsorp- tion capacity increased with the increase in the pore size in micropores and decreased with the increase in the pore size in mesopores. The methane excess adsorption capacity in chlorite pores increased with an increase in pressure or decrease in pore size. With an increase in temperature, the isosteric heats of adsorption of methane decreased and the methane adsorption sites on chlorite changed from lower- energy adsorption sites to higher-energy sites, leading to the reduction in the methane excess adsorption capacity. Water molecules in chlorite pores occupied the pore wall in a directional manner, which may be related to the van der Waals and Coulomb force interactions and the hydrogen bonding interaction. It was also found that water molecules existed as aggregates. With increasing water content, the water molecules occupied the adsorption sites and adsorption space of the methane, leading to a reduction in the methane excess adsorption capacity. The excess adsorption capacity of gas on chlorite decreased in the following order： carbon dioxide 〉 methane 〉 nitrogen. If the mole fraction of nitrogen or carbon dioxide in the binary gas mixture increased, the mole fraction of methane decreased, methane adsorption sites changed, and methane adsorption space was reduced, resulting in the decrease in the methane excess adsorption capacity.

关键词： Chlorite Methane Nanopores Grandcanonical Monte Carlo Adsorption capacity

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Optimal Time Decay of Navier–Stokes Equations with Low Regularity Initial Data

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Acta Mathematica Sinica,English Series 2018年第5期34卷 855-872页

作者： jun xiong JIA Department of Mathematics Xi’an Jiaotong University Beijing Center for Mathematics and Information Interdisciplinary Sciences (BCMIIS)

In this paper, we study the optimal time decay rate of isentropic Navier-Stokes equations under the low regularity assumptions about initial data. In the previous works about optimal time decay rate, the initial data need to be small in H^[N/2]＋2（R^N）. Our work combined negative Besov space estimates and the conventional energy estimates in Besov space framework which is developed by Danchim Through our methods, we can get optimal time decay rate with initial data just small in B^N/2-1,N/2＋1∩^N/2-1,N/2 and belong to some negative Besov space （need not to be small）. Finally, combining the recent results in [25] with our methods, we only need the initial data to be small in homogeneous Besov space B^N/2-2,N/2 ∩B^N/2-1 to get the optimal time decay rate in space L2.

关键词： Compressible fluids besov space framework optimal time decay negative Besov space

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Discrimination of Motor Imagery Patterns by Electroencephalogram Phase Synchronization Combined With Frequency Band Energy

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IEEE/CAA Journal of Automatica Sinica 2017年第3期4卷 551-557页

作者： Chuanwei liu Yunfa Fu jun Yang Xin xiong Huiwen Sun Zhengtao Yu Faculty of Information Engineering and Automation Kunming University Science and Technology Shanghai Micro Electronics Equipment Co. Ltd. (SMEE)

Central nerve signal evoked by thoughts can be directly used to control a robot or prosthetic devices without the involvement of the peripheral nerve and *** is a new strategy of human-computer interaction.A method of electroencephalogram(EEG) phase synchronization combined with band energy was proposed to construct a feature vector for pattern recognition of brain-computer interaction based on EEG induced by motor imagery in this paper,rhythm and beta rhythm were first extracted from EEG by band pass filter and then the frequency band energy was calculated by the sliding time window;the instantaneous phase values were obtained using Hilbert transform and then the phase synchronization feature was calculated by the phase locking value(PLV) and the best time interval for extracting the phase synchronization feature was searched by the distribution of the PLV value in the time ***,discrimination of motor imagery patterns was performed by the support vector machine(SVM).The results showed that the phase synchronization feature more effective in4s-7s and the correct classification rate was 91.4%.Compared with the results achieved by a single EEG feature related to motor imagery,the correct classification rate was improved by 3.5 and4.3 percentage points by combining phase synchronization with band *** indicate that the proposed method is effective and it is expected that the study provides a way to improve the performance of the online real-time brain-computer interaction control system based on EEG related to motor imagery.

关键词： Brain-computer interaction(BCI) electroencephalogram(EEG) frequency band energy motor imagery phase synchronization

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Wind erodibility indices of aeolian sandy soils impacted by different vegetation restoration:a case study from the Shannan valley of the Yarlung Zangbo River

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Journal of Mountain Science 2022年第10期19卷 2830-2845页

作者： ZHANG Bao-jun xiong Dong-hong liu Lin TANG Yong-fa Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu 610041China College of Water Conservancy and Hydropower Engineering Sichuan Agricultural UniversityYa'an 625014China

Controlling aeolian desertification is a key ecological target on the Tibetan Plateau,especially within the widespread river *** recovery can change the near-soil surface characteristics,which thus may influence wind erodibility of ***,these potential effects are not sufficiently evaluated for aeolian sandy *** study selected the Shannan valley of the Yarlung Zangbo River on the southern Tibetan Plateau as a case to investigate the variations in wind erodibility of aeolian sandy soils impacted by different vegetation restoration,since many ecological measures have been implemented in recent decades in the river *** vegetated sandy lands with different restoration types and ages and two bare sandy lands(as controls)were chosen as test *** vegetated sandy lands were covered by Artemisia wellbyi,Hedysarum scoparium,Sophora moorcroftiana,and Populus *** the similar restoration age of 10 *** Sophora moorcroftiana and Populus ***,two restoration ages of 6 and over 30 years were also selected *** erodibility was reflected by wind erodible fraction(EF),mean weight diameter of dry aggregates(MWD),capillary water capacity(CWC),soil cohesion(CS),and soil penetration resistance(PR)from different aspects.A comprehensive wind erodibility index(CWEI)was further produced by a weighted summation method to combine those five indices together and comprehensively quantify the effects of vegetation restoration on wind erodibility of aeolian sandy *** results showed that revegetation was efficient to reduce wind erodibility of aeolian sandy *** generally decreased,while MWD,CWC,CS,and PR increased after vegetation restoration on the aeolian sandy *** CWEI of vegetated sandy lands varied greatly from 0.850 to 0 under different restoration types and ages and decreased by 14.4%to 100%compared to the *** the four different restoration types,Populus *** the relatively minimum CWEI,fol

关键词： Wind erosion Soil erodibility Erodible fraction Vegetation type Ecological restoration Yarlung Zangbo River valley

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