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西秦岭三叠纪大河坝组砂岩构造背景与物质来源

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西北地质 2024年第3期57卷 113-127,I0002页

作者：李康宁汤庆艳栾晓刚王玉玺邓小华杨宗枫兰州大学地质科学与矿产资源学院甘肃兰州730000 甘肃省地质矿产勘查开发局第三地质矿产勘查院甘肃兰州730050 夏河县冰华矿业有限责任公司甘肃甘南747100 长安大学地球科学与资源学院陕西西安710064

大河坝组是西秦岭夏河–碌曲地区出露最晚的一套海相地层,记录了印支期海退事件。笔者基于大河坝组层序特征、砂岩主微量元素成分和碎屑锆石U-Pb年龄基础上,探索其物质来源特征和构造背景指示意义。大河坝组主体为砂板岩复理石建造,包... 详细信息

大河坝组是西秦岭夏河–碌曲地区出露最晚的一套海相地层,记录了印支期海退事件。笔者基于大河坝组层序特征、砂岩主微量元素成分和碎屑锆石U-Pb年龄基础上,探索其物质来源特征和构造背景指示意义。大河坝组主体为砂板岩复理石建造,包括长石砂岩、岩屑长石砂岩、含砾岩屑长石砂岩等。其中,砂岩具有中等SiO_(2)(64.11%~68.27%,平均为65.45%),较高Al_(2)O_(3)(13.61%~15.19%,平均为14.51%),较低Fe2O_(3)(0.82%~1.72%,平均为1.25%)、CaO(2.39%~3.32%,平均为3.06%)、MgO(0.06%~0.10%,平均为0.08%)特征。稀土元素总量较高,ΣREE值为184×10^(-6)~434×10^(-6),平均为252×10^(-6)。球粒陨石标准化图解中显示Eu负异常,具有与活动大陆边缘环境相似的Th、Zr、Ti、Co、Ni等微量元素含量。砂岩中碎屑锆石U-Pb年龄主要为2204~2520 Ma、1536~2067Ma、253.3~448.7Ma等3个阶段,在2445Ma、1986.4Ma、1757.6Ma、448.5Ma、278.2Ma等5个年龄段出现峰值,锆石最小年龄为253.3 Ma。砂岩主微量元素分析和碎屑锆石U-Pb年代学谱系显示,大河坝组源区构造环境为活动大陆边缘,碎屑物质来自上地壳中性火成岩,主要物源区为研究区北部北秦岭构造带、祁连造山带东段和华北板块南缘基底,少部分碎屑来自西秦岭同期岩浆岩和多旋回沉积物。

关键词：大河坝组碎屑锆石构造环境物源西秦岭造山带

Revisiting the false positive rate in detecting recent positive selection

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Frontiers of Electrical and Electronic Engineering in China 2016年第3期4卷 207-216页

作者： Jinggong Xiang-Yu zongfeng yang Haipeng Li CAS Key Laboratory of Computational Biology CAS-MPG Parter Institute for Computational Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China University of Chinese Academy of Sciences Beijing 100049 China

There is increasing interest in studying the molecular mechanisms of recent adaptations caused by positive selection in the genomics era. Such endeavors to detect recent positive selection, however, have been severely handicapped by false positives due to the confounding impact of demography and the population structure. To reduce false positives, it is critical to conduct a functional analysis to identify the true candidate genes/mutations from those that are filtered through neutrality tests. However, the extremely high cost of such functional analysis may restrict studies within a small number of model species. In particular, when the false positive rate of neutrality tests is high, the efficiency of the functional analysis will also be very low. Therefore, although the recent improvements have been made in the （joint） inference of demography and selection, our ultimate goal, which is to understand the mechanism of adaptation generally in a wide variety of natural populations, may not be achieved using the currently available approaches. More attention should thus be spent on the development of more reliable tests that could not only free themselves from the confounding impact of demography and the population structure but also have reasonable power to detect selection.

关键词： recent positive selection selective sweep demography population structure false positive

Crystal Growth and Crystallization Time Scales of the Panzhihua Layered Intrusion:Constraint from Crystal Size Distribution

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Acta Geologica Sinica(English Edition) 2020年第5期94卷 1428-1439页

作者： LI Xuejun LUO Zhaohua LI Xiaowei WANG Yu yang zongfeng LI Jie LIU Xiao State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesBeijing 100083China

The Panzhihua layered intrusions is generated closely related to the Emeishan *** paper analyzes the spatial distribution of plagioclase and *** quantitative texture analysis of 2209 plagioclase shows that the characteristic length of plagioclase is 0.54 to 0.96 mm,the intercept variation range is large,from-0.67 to 0.96,and the slope is-1.85 to-1.04,the Aspect Ratio shows from 1.84 to 2.59 and fractal dimension D is 1.908–*** quantitative texture analysis of 2342 pyroxene shows that the characteristic length of pyroxene is 0.38–0.64 mm,the intercept shows from 0.46 to 2.26,The slope ranges from-2.6 to-1.47,the Aspect Ratio value varies from 1.53 to 1.71,the fractal dimension D is 0.93 to *** the CSDs results of the Panzhihua intrusions indicate that plagioclase and pyroxene form in an open magma system and undergo four replenishment of magma *** plagioclase crystals do not grow as the lathlike shape,and the fractal growth leads to complex crystal *** plagioclase undergoes deformation compaction during the crystal process,and then is *** pyroxene crystals grow along an approximately triaxial ratio and undergo texture adjustment and small crystal dissolution *** all crystals in magma system grows up to 2 mm,the pyroxene undergoes cumulation in the Panzhihua layered *** plagioclase crystallization time scale is 171.23–304.41 years,representing that the crystallization is the more uniform in central part of the *** nucleation density continuously increases during the crystallization process of the magma *** time scale to reach the final maximum crystal nucleation density is 15.28–58.98 years.

关键词： crystal size distribution crystallization time scales layered intrusions Emeishan large igneous province Panzhihua

Minimum critical thickness of dike for ore-bearing fluid injection:A new approach applied to the Shihu gold deposit,Hebei Province,North China

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Geoscience Frontiers 2012年第5期3卷 717-728页

作者： Dedong Li Yuwang Wang Jingbin Wang Zhaohua Luo Jiulong Zhou zongfeng yang Cui Liu Beijing Institute of Geology for Mineral Resources Beijing 100012 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China

According to the metallogenic theory by transmagmatic fluid （TMF）, one magmatic intrusion is a channel of ore-bearing fluids, but not their source. Therefore, it is possible to use TMF＇s ability for injection into and for escaping t^om the magmatic intrusion to evaluate its ore-forming potential. As the ore-bearing fluids cannot effectively inject into the magmatic intrusion when the magma fully crystal- lized, the cooling time and rates viscosity varied can be used to estimate the minimum critical thickness of the intrusion. One dimensional heat transfer model is used to determine the cooling time for three representative dikes of different composition （granite porphyry, quartz diorite and diabase） in the Shihu gold deposit. It also estimated the rates viscosity varied in these time interval. We took the thickness of dike at the intersection of the cooling time -- thickness curve and the rates viscosity varied versus thick- ness curve as the minimum critical thickness. For the ore-bearing fluids effectively injecting into the magma, the minimum critical thicknesses for the three representative dikes are 33.45 m for granite porphyry, 8.22 m for quartz diorite and 1.02 m for diabase, indicating that ore-bearing dikes must be thicker than each value. These results are consistent with the occurrence of ore bodies, and thus they could be applied in practice. Based on the statistical relationship between the length and the width of dikes, these critical thicknesses are used to compute critical areas： 0.0003--0.0016 km2 for diabase, 0.014--0.068 km2 for quartz diorite and 0.011-0.034 km2 for granite porphyry. This implies that ore- bearing minor intrusions have varied areas corresponding to their composition. The numerical simulation has provided the theoretical threshold of exposed thickness and area of the ore-bearing intrusion. These values can be used to determine the ore-forming potentials of dikes.

关键词： Dike swarm Cooling time Numerical simulationMinor intrusion Critical thickness Transmagmatic fluid

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流量时代城市敏捷治理体系及启示

东岳论丛 2024年第4期45卷 133-144,192页

作者：孙宗锋杨志山东大学政治学与公共管理学院山东青岛266237

如何有效应对流量时代的城市治理挑战,是公共管理研究的重要内容。流量时代城市治理应该具备敏捷治理的基本特性,需要多元治理主体快速响应,达到市场有效、政府有为、社会有序、公民有情的理想效果。具体而言,市委、市政府要勇于担当、... 详细信息

如何有效应对流量时代的城市治理挑战,是公共管理研究的重要内容。流量时代城市治理应该具备敏捷治理的基本特性,需要多元治理主体快速响应,达到市场有效、政府有为、社会有序、公民有情的理想效果。具体而言,市委、市政府要勇于担当、顺势而为;各级政府部门成立专班,快速横向纵向联动;社会组织积极参与,广泛动员各方力量;公民发扬公共情怀,奋力守卫城市形象。流量时代的城市治理既不同于以往的运动式治理,也不同于疫情防控时期的应急管理,而是一种跨越传统行政区划且需要城市治理主体快速响应的新模式。

关键词：流量时代城市治理敏捷治理

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不平衡电网电压下基于滑模变结构控制的双馈风电系统转子侧变流器控制策略

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电工技术学报 2016年第17期31卷 121-131页

作者：张迪魏艳君杨宗丰丁浩漆汉宏燕山大学电气工程学院秦皇岛066004

在两相静止坐标系下,建立了基于功率控制的双馈电机统一的数学模型,该模型在平衡和不平衡电网电压条件下均适用。采用基于滑模变结构的直接功率控制方法实现了对双馈风电系统转子侧变流器的控制,该方法控制结构简单,动态响应快,鲁棒性... 详细信息

在两相静止坐标系下,建立了基于功率控制的双馈电机统一的数学模型,该模型在平衡和不平衡电网电压条件下均适用。采用基于滑模变结构的直接功率控制方法实现了对双馈风电系统转子侧变流器的控制,该方法控制结构简单,动态响应快,鲁棒性强。在不平衡电网电压条件下,提出了一种新型的功率优化补偿控制策略。该控制策略可直接对转子侧变换器的功率给定进行补偿,无需对定、转子电流进行正、负序分解,简化了系统控制结构;更重要的是其能有效降低定子电流扰动对功率补偿量的影响,系统鲁棒性得到明显提高。仿真和实验结果均证明了该控制策略的正确性和有效性。

关键词：双馈电机转子侧变换器滑模变结构控制直接功率控制不平衡电网电压

运用定量化结构分析方法揭示蚀变花岗斑岩的形成过程——以新疆莫阿特茂金岩体为例

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地质科学 2015年第1期50卷 118-139页

作者：徐飞罗照华杨宗锋聂高众中国地震局地壳应力研究所北京100085 中国地质大学北京100083 中国地震局地质研究所北京100029

地球化学分析方法已广泛运用于火成岩成因的研究中,但对于一些蚀变较严重的岩石,有时仅通过地球化学分析难以还原岩浆固结的过程。火成岩定量化结构分析方法是通过对岩石中矿物的定量分析(诸如晶体粒度分布分析,晶体空间分布分析,以及... 详细信息

地球化学分析方法已广泛运用于火成岩成因的研究中,但对于一些蚀变较严重的岩石,有时仅通过地球化学分析难以还原岩浆固结的过程。火成岩定量化结构分析方法是通过对岩石中矿物的定量分析(诸如晶体粒度分布分析,晶体空间分布分析,以及晶体定向程度分析等),从而反演岩浆固结过程中发生的动力学过程。这种方法很好地避免了蚀变作用对还原岩体形成过程所产生的诸多影响。本文运用火成岩定量化结构分析方法,对新疆莫阿特茂金花岗斑岩体钻孔中10个样品的钾长石斑晶和石英斑晶分别进行分析。尽管这些样品普遍发生了碳酸盐化蚀变作用,定性观察中结构特征也比较均一,但是钾长石和石英斑晶的定量化结构数据及其在钻孔深度(约170 m)范围内的变化趋势显示,茂金花岗斑岩体可能至少由4次脉冲岩浆叠加形成,每股岩浆中心的CSD曲线小晶体缺乏,发生了粗化现象。由于脉冲式岩浆多次注入,导致的温度振荡加剧了矿物粗化。脉冲岩浆中心处斑晶体积含量的增加,可能与岩浆流动过程中对大晶体的影响有关,80 m深度以下脉冲岩浆接触带的斑晶体积含量明显增加,是由于机械压缩导致的。

关键词：晶体粒度分布空间分布花岗斑岩莫阿特新疆

Prenatal ultrasonic characteristics and diagnosis of fetal Currarino syndrome:Report of 2 cases and review of literature

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中国医学影像技术 2024年第8期40卷 1212-1215页

作者： WEI Yingni ZHANG Yuchen DENG zongfeng WANG Yingqiu HUANG Qiaojie CHEN Yayan Department of Ultrasound Shenzhen Longhua Maternity&Child Healthcare HospitalShenzhen 518110China

Objective To explore prenatal ultrasonic characteristics of fetal Currarino syndrome(CS)and methods for prenatal diagnosis of *** Two fetuses with CS confirmed by genetic examination were retrospectively analyzed,while 6 CS fetuses with complete prenatal ultrasonic data in literature were *** ultrasonic characteristics of CS fetuses and the method for prenatal diagnosis of CS were *** Among 8 CS fetuses diagnosed with prenatal ultrasound,4 were female singletons with a clear family history of CS,and MNX 1 gene mutation was found in 1 *** other 4 fetuses were 2 pairs of male monochorionic twins,all with MNX 1 gene *** 8 CS fetuses,complete triad(sacral agenesis abnormalities,anorectal malformation and presacral mass)were displayed only in 2 fetuses,while all 8 had sacral agenesis abnormalities and 6(6/8,75.00%)were detected with prenatal ultrasound,6 had low location of conus medullaris and 2(2/6,33.33%)detected with prenatal *** Prenatal ultrasound was the first choice for non-invasive diagnosis of fetal *** one of sacral agenesis abnormalities,anorectal malformation and presacral mass was found with prenatal ultrasound,the possibility of CS should be considered,and fetal MRI,genetic examination and prenatal genetic counselling should be recommended if necessary.

关键词： Currarino triad ultrasonography,prenatal amniocentesis genes

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火成岩中的超临界流体晶及其研究意义

地学前缘 2019年第6期26卷 216-227页

作者：罗照华杨宗锋苏尚国刘翠江秀敏中国地质大学(北京)地质过程与矿产资源国家重点实验室

流行火成岩理论中,岩浆被默认为自然熔体,因而火成岩中的矿物晶体都形成于熔体的结晶作用,可称为熔体晶。许多证据表明,火成岩中也可以含有从超临界流体析出的晶体,被称为超临界流体晶(文中简称为流体晶)。根据三个典型实例分析,流体晶... 详细信息

流行火成岩理论中,岩浆被默认为自然熔体,因而火成岩中的矿物晶体都形成于熔体的结晶作用,可称为熔体晶。许多证据表明,火成岩中也可以含有从超临界流体析出的晶体,被称为超临界流体晶(文中简称为流体晶)。根据三个典型实例分析,流体晶既可以从超临界流体直接析出,类似于从热液析出晶体的过程;也可以由超临界流体浓缩产生的熔体结晶形成。不管是哪一种晶出方式,流体晶产生的前提都是岩浆达到流体过饱和态;而满足这一前提的基本条件则是透岩浆流体过程和岩浆快速上升。结合前人关于熔体-流体平衡条件的研究进展,以及熔体黏度对挥发分含量和岩浆上升速度对熔体黏度的依赖,发现透岩浆流体过程与岩浆上升过程之间具有耦合关系,这种关系可以用来阐明岩浆系统行为非线性变化的原因。流体晶的研究具有重要意义,可用于:(1)提供一种研究岩浆系统流体条件的新途径;(2)揭示岩浆系统偏离理想态的程度;(3)为反演岩浆系统动力学过程提供新的约束;(4)为识别致矿侵入体和评估侵入体的找矿潜力提供新的矿物学标志;(5)理解火成岩理论中一些长期得不到解决的问题,如岩浆中挥发分溶解度问题、冻结岩浆的活化问题、岩浆成矿专属性问题。

关键词：流体晶透岩浆流体挥发分减压卸载溶解度熔体