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Tourmaline geochemistry and boron isotopic variations as a guide to fluid evolution in the Qiman Tagh W-Sn belt, East Kunlun, China

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Geoscience Frontiers 2019年第2期10卷 569-580页

作者： zhen zheng Yanjing Chen Xiaohua Deng Suwei Yue Hongjin Chen Qingfei Wang State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences (Beijing) State Key Laboratory for Mineral Deposits Research Department of Earth SciencesNanjing University Key Laboratory of Orogen and Crust Evolution Peking University Beijing Institute of Geology for Mineral Resources Guangzhou College South China University of Technology

The Qiman Tagh W-Sn belt lies in the westernmost section of the East Kunlun Orogen, NW China, and is associated with early Paleozoic monzogranites, tourmaline is present throughout this belt. In this paper we report chemical and boron isotopic compositions of tourmaline from wall rocks, monzogranites, and quartz veins within the belt, for studying the evolution of ore-forming fluids. Tourmaline crystals hosted in the monzogranite and wall rocks belong to the alkali group, while those hosted in quartz veins belong to both the alkali and X-site vacancy groups. Tourmaline in the walk rocks lies within the schorl-dravite series and becomes increasingly schorlitic in the monzogranite and quartz veins. Detrital tourmaline in the wall rocks is commonly both optically and chemically zoned,with cores being enriched in Mg compared with the rims. In the Al-Fe-Mg and Ca-Fe-Mg diagrams,tourmaline from the wall rocks plots in the fields of Al-saturated and Ca-poor metapelite, and extends into the field of Li-poor granites, while those from the monzogranite and quartz veins lie within the field of Li-poor granites. Compositional substitution is best represented by the MgFe_(-1), Al(NaR)_(-1), and AlO(Fe(OH))_(-1) exchange vectors. A wider range of δ^(11)B values from -11.1‰ to -7.1‰ is observed in the wall-rock tourmaline crystals, the B isotopic values combining with elemental diagrams indicate a source of metasediments without marine evaporates for the wall rocks in the Qiman Tagh belt. The δ^(11)B values of monzogranite-hosted tourmaline range from -10.7‰ and-9.2‰, corresponding to the continental crust sediments, and indicate a possible connection between the wall rocks and the monzogranite. The overlap in δ^(11)B values between wall rocks and monzogranite implies that a transfer of δ^(11)B values by anataxis with little isotopic fractionation between tourmaline and melts. Tourmaline crystals from quartz veins have δ^(11)B values between -11.0‰ and-9.6‰, combining with the ele

关键词： Tourmaline Chemical composition Boron isotope Qiman Tagh W-Sn belt Fluid evolution

The breaking of spin symmetry in the single-particle resonances in deformed nuclei

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Nuclear Science and Techniques 2024年第3期35卷 237-245页

作者： zhen-Yu zheng Shou-Wan Chen Quan Liu School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China

The exploration of spin symmetry (SS) in nuclear physics has been instrumental in identifying atomic nucleus *** this study,we solve the Dirac equation from the relativistic mean field (RMF) in complex momentum *** investigated SS and its breaking in single-particle resonant states within deformed nuclei,with a focus on the illustrative *** was the initial discovery of a resonant spin doublet in a deformed nucleus,with the expectation of the SS approaching the continuum *** increasing single-particle energy,the splitting of the resonant spin doublets widened *** escalating splitting implies diminishing adherence to the SS,indicating a departure from the expected behavior as the energy levels *** also analyzed the width of the resonant states,showing that lower orbital angular momentum resonances possess shorter decay times and that SS is preserved within broad resonant doublets,as opposed to narrow resonant *** the radial density of the upper components for the bound-state and resonant-state doublets,it becomes evident that while SS is well-preserved in the bound states,it deteriorates in the resonant *** impact of nuclear deformation (β_(2)) on SS was examined,demonstrating that an increase in β_(2) resulted in higher energy and width splitting in the resonant spin doublets,which is attributed to increased component ***,the sensitivity of spin doublets to various potential parameters such as surface diffuseness (a),radius (R),and depth (Σ0) is discussed,emphasizing the role of these parameters in *** study provides valuable insights into the behavior of spin doublets in deformed nuclei and their interplay with the nuclear structure,thereby advancing our understanding of SS in the resonance state.

关键词： Spin symmetry Resonant states Deformed nuclei Complex-momentum representation

基于机理的蒸汽裂解模型在生产计划优化中的应用探索

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化工生产与技术 2024年第1期30卷 33-38,I0004,I0005页

作者：赖清俊郑真魏跃峰吴海东中科(广东)炼化有限公司广东湛江524076 石化盈科信息技术有限责任公司北京100020

以某炼化一体化企业的乙烯蒸汽裂解装置为例,生产计划优化模型实现与蒸汽裂解机理模型的无缝集成是非常有意义的探索。介绍了乙烯蒸汽裂解装置在生产计划优化模型中采用非线性建模技术,集成了裂解炉模拟机理模型,并采用回归工具得到适... 详细信息

以某炼化一体化企业的乙烯蒸汽裂解装置为例,生产计划优化模型实现与蒸汽裂解机理模型的无缝集成是非常有意义的探索。介绍了乙烯蒸汽裂解装置在生产计划优化模型中采用非线性建模技术,集成了裂解炉模拟机理模型,并采用回归工具得到适用于生产计划优化模型的外挂机理模型XLP文件,用于模型的优化计算,可优选乙烯原料选择、优化裂解操作参数,得到更加精确的装置收率计算结果,实现从原油到石脑油的性质传递和计算,提高了企业计划优化模型的精细化水平,为企业优化生产、降本增效提供了有力支撑。

关键词：蒸汽裂解非线性模型机理模型计划优化模型

联合全基因组关联和转录组分析筛选玉米拟轮枝镰孢穗腐病的抗性候选基因

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作物学报 2024年第9期50卷 2279-2296页

作者：叶靓朱叶琳裴琳婧张思颖左雪倩李正真刘芳谭静云南大学农学院云南昆明650500

玉米是我国第一大粮食作物,实现玉米的高产稳产对于我国粮食安全、农业稳定有重要意义。穗腐病是一种严重危害全球玉米的真菌性病害,会造成玉米大幅减产和品质劣变。本研究选用我国玉米穗腐病的优势致病菌拟轮枝镰孢(Fusariumverticilli... 详细信息

玉米是我国第一大粮食作物,实现玉米的高产稳产对于我国粮食安全、农业稳定有重要意义。穗腐病是一种严重危害全球玉米的真菌性病害,会造成玉米大幅减产和品质劣变。本研究选用我国玉米穗腐病的优势致病菌拟轮枝镰孢(Fusariumverticillioides),对241份来源广泛的玉米自交系进行2年田间人工接种抗性鉴定,同时利用20,586个高质量SNP标记通过全基因组关联分析(genome-wideassociationstudy,GWAS),鉴定拟轮枝镰孢穗腐病抗性显著关联的SNP位点;在此基础上选取对拟轮枝镰孢穗腐病表现高抗和高感的玉米自交系各1份,其籽粒在室内接种拟轮枝镰孢,通过对3个不同侵染时间的籽粒进行转录组测序(RNA-seq),分析抗感材料差异表达基因(differentiallyexpressedgenes,DEGs)及其富集情况;结合GWAS和RNA-seq结果,共同定位筛选抗病候选基因。主要研究结果如下:(1)综合2年田间抗性鉴定结果,筛选到4份抗拟轮枝镰孢穗腐病的玉米自交系,其中含有热带血缘的玉米种质对拟轮枝镰孢穗腐病表现出更好的抗性。(2)2年GWAS分析共检测到26个与拟轮枝镰孢穗腐病抗性显著关联的SNP位点,其中有18个位点位于前人定位到的QTL范围内。(3) RNA-seq结果表明,抗感材料对病原菌的响应基因不同。与感病材料相比,抗病材料均显示出更多的DEGs,且都有更多的上调基因;在抗感材料特异性DEGs共同富集的GO条目和KEGG通路中,抗病材料中富集到的DEGs占比显著多于感病材料;一些与植物防御病原菌相关的条目和通路也仅在抗病材料中被特异富集。(4)在GWAS检测到的显著关联位点上下游100 kb范围内筛选与转录组DEGs共同定位到的候选基因,结果 16个基因被GWAS和RNA-seq同时检测到;根据这些基因的蛋白功能及相关文献报道,从中预测到6个与拟轮枝镰孢穗腐病抗性相关的候选基因。综上所述,本研究筛选出4份抗拟轮枝镰孢穗腐病的玉米自交系,来自热带、亚热带的玉米种质可以作为抗逆性品种选育的研究重点;对抗感玉米自交系响应拟轮枝镰孢侵染的DEGs及其相关抗病机制进行了初步解析,联合GWAS和RNA-seq共定位到6个与拟轮枝镰孢穗腐病抗性相关的候选基因,研究结果为玉米穗腐病抗性基因的克隆验证与抗性品种的培育提供了一定的理论依据。

关键词：玉米穗腐病拟轮枝镰孢关联分析转录组分析抗性种质候选基因

Research on the Key Issues of Wireless Mobile Ad Hoc Networks

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The Journal of China Universities of Posts and Telecommunications 2005年第3期12卷 1-6页

作者： YANG zhen zheng Bao-yu Nanjing University of Posts & Telecommunications Nanjing 210003 P.R. China

Communication Network and Signal Processing are two of the research hotspots in the field of information technology because of their fast development. This paper focuses on the introduction of some research progresses in our National 863 Project based on the combination of technologies in these two areas. We present two new Medium Access Control （MAC） protocols based on so-called Multi-Packets Reception （MPR） in Ad hoc networks. Communication in the first scheme is initiated from senders and from receivers in the second one. Simulation results show that these new MAC protocols, which are based on new signal processing techniques, may raise network capacity and reduce transmission delay of data from end to end.

关键词： Ad hoc MAC MPR

血清CRP/ALB、HCY/HDL-C及NT-proBNP水平与冠脉综合征患者冠脉病变程度的关系

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医药论坛杂志 2024年第7期45卷 710-714,718页

作者：位培林瑞芳郑淑贞刘英利河南省荣军医院心血管内科河南新乡453000

目的探究血清C反应蛋白/白蛋白比值(CRP/ALB)、同型半胱氨酸/高密度脂蛋白胆固醇比值(HCY/HDL-C)、N末端脑钠肽前体(NT-proBNP)水平与冠脉综合征患者冠脉病变程度的关系。方法纳入2021年1月至2023年5月在河南省荣军医院行冠脉造影手术... 详细信息

目的探究血清C反应蛋白/白蛋白比值(CRP/ALB)、同型半胱氨酸/高密度脂蛋白胆固醇比值(HCY/HDL-C)、N末端脑钠肽前体(NT-proBNP)水平与冠脉综合征患者冠脉病变程度的关系。方法纳入2021年1月至2023年5月在河南省荣军医院行冠脉造影手术并明确诊断冠心病患者100例,依据Gensini积分分为轻度病变组(积分中度病变组>重度病变组(P<0.05)。CRP、CRP/ALB、HCY、HCY/HDL-C以及NT-proBNP均与Gensini积分呈正相关(P<0.05),ALB与Gensini积分呈负相关(P<0.05)。在CRP、CRP/ALB、HCY、HCY/HDL-C以及NT-proBNP水平比较上,非重度病变组<重度病变组(P<0.05),但非重度病变组ALB水平高于重度病变组(P<0.05)。logistic回归分析发现CRP/ALB、HCY/HDL-C、NT-proBNP是冠脉重度病变发生的危险因素(P<0.05)。CRP/ALB、HCY/HDL-C、NT-proBNP诊断重度冠脉病变的AUC分别为0.817、0.821、0.825(P<0.05)。结论CRP/ALB、HCY/HDL-C、NT-proBNP可能是冠脉综合征患者冠脉重度病变的危险因素,且冠脉病变越重,患者的CRP/ALB、HCY/HDL-C、NT-proBNP水平越高。

关键词：冠脉综合征 C反应蛋白/白蛋白同型半胱氨酸/高密度脂蛋白胆固醇 N末端脑钠肽前体

Stability and accuracy of central difference method for real-time dynamic substructure testing considering mass participation coefficient

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 625-636页

作者： zheng Lichang Xu Guoshan Yang Ge Wang zhen Yang Kaibo zheng zhenyun School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Key Lab of Structures Dynamic Behavior and Control Ministry of EducationHarbin Institute of TechnologyHarbin 150090China Key Lab of Intelligent Disaster Mitigation Ministry of Industry and Information TechnologyHarbin 150090China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China

For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been ***,this study proposes to investigate the stability and accuracy of the central difference method(CDM)for RTDST considering the specimen mass participation ***,the theory of the CDM for RTDST is ***,the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are ***,numerical simulations and experimental tests are conducted for verifying the effectiveness of the *** study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen,and the stability limit first increases and then decreases as the mass participation coefficient *** most cases,the mass participation coefficient will increase the stability limit of the algorithm,but in specific circumstances,the algorithm may lose its *** stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper.

关键词： real-time dynamic substructure testing central difference method stability mass participation coefficient tuned liquid damper

Effect of compression on the liquid absorption of Chinese fir wood with different heartwood-to-sapwood ratios

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Forestry Studies in China 2009年第3期11卷 196-201页

作者： MAO Jia CAO Jin-zhen zheng Xin College of Materials Science and Technology Beijing Forestry University Beijing 100083 P. R. China

In this study, the Chinese fir （Cunninghamia lanceolata Hook.） specimens with different ratios of heartwood thickness to sapwood thickness （HS） were radially compressed at different compression speeds, and then absorbed amine copper quat-type D （ACQ-D） preservative solution under the negative-pressure produced by the recovery of compression deformation. The liquid uptake （Al）, the recovery rate of compression deformation （Rs） and the chemical absorption （Ac） of samples were determined, as well as the overall distribution of density and effective component of ACQ-D （i.e., copper in wood）, the mechanical properties such as surface hardness were also measured. The Al, Rs, Ac values of compressed samples including the whole heartwood ones were higher than those of uncompressed samples, showing that radial compression had an obvious positive effect on improving the liquid absorption of heartwood. Higher compression speed of 3 ***^-1 is preferable since the samples with that speed could reach the highest Al and Ac; in addition, more deformation fixation has been produced possibly because of the faster heat and moisture transmission at the higher compressed speed, and more bonds of hydrophobic nature were formed, leading to the higher surface hardness and density. A consistent tendency of the density distribution and the copper retentions along the thickness direction could be explained that the layers with higher density have smaller volumes of void areas, and more chemicals were absorbed and fixed, resulting in the higher copper retentions.

关键词： Chinese fir penetration density distribution heartwood compression

FRP筋与水泥浆界面粘结滑移特性数值模拟研究

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兰州理工大学学报 2024年第4期50卷 135-141页

作者：王正振梁锦添戴国亮周勇靳高明王金科兰州理工大学土木工程学院甘肃兰州730050 东南大学土木工程学院南京210096 河西学院甘肃张掖734000 甘肃建投建设有限公司甘肃兰州730050

基于试验和数值模拟方法研究FRP筋与水泥浆的粘结特性与不同因素对其粘结行为的影响.以有限元软件中的Cohesive单元模拟FRP筋与水泥浆之间的界面粘结滑移,以混凝土塑性损伤模型模拟水泥浆体的损伤与破坏行为.按试验工况及加载条件建立FR... 详细信息

基于试验和数值模拟方法研究FRP筋与水泥浆的粘结特性与不同因素对其粘结行为的影响.以有限元软件中的Cohesive单元模拟FRP筋与水泥浆之间的界面粘结滑移,以混凝土塑性损伤模型模拟水泥浆体的损伤与破坏行为.按试验工况及加载条件建立FRP筋-水泥浆界面粘结滑移模型.通过控制变量法研究了FRP筋类型、直径、长度等因素对界面粘结行为、粘结应力分布和破坏机制的影响。结果表明:不同纤维材料的粘结性能差异较大;增大粘结长度、筋材直径能够提高极限承载力;在加载过程中,FRP筋体轴力主要分布在加载端,随着荷载增加,靠近加载端的筋体轴力增幅大于粘结段末端;拉拔荷载达到峰值时,界面粘结单元开始破坏、界面粘结单元发生损伤,粘结强度不断下降;随着粘结-滑移曲线进入下降段,界面粘结作用逐渐失效,构件完全破坏.

关键词： FRP筋水泥浆粘结性能有限元模拟