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北祁连洋早古生代双向俯冲的花岗岩证据

中国地质 2006年第6期33卷 1197-1208页

作者：吴才来姚尚志杨经绥曾令森陈松永李海兵戚学祥 Joseph L. Wooden frank k.mazdab 中国地质科学院地质研究所北京100037 安徽省地质调查院安徽合肥230001 斯坦福大学

笔者主要对北祁连山中段的牛心山岩体、民乐窑沟岩体进行了锆石SHRIMP定年研究。结果表明:牛心山花岗岩的年龄为476 Ma,民乐窑沟花岗闪长岩的年龄为463 Ma。岩石地球化学显示,两岩体均具有大陆活动边缘的岩浆作用特征,结合岩体产出的区... 详细信息

笔者主要对北祁连山中段的牛心山岩体、民乐窑沟岩体进行了锆石SHRIMP定年研究。结果表明:牛心山花岗岩的年龄为476 Ma,民乐窑沟花岗闪长岩的年龄为463 Ma。岩石地球化学显示,两岩体均具有大陆活动边缘的岩浆作用特征,结合岩体产出的区域构造位置及区域地质资料,笔者认为早古生代北祁连洋板块分别发生了向南、向北俯冲,其中向南俯冲形成牛心山花岗岩(476 Ma),向北俯冲,形成了民乐窑沟花岗岩侵入体(463 Ma)。

关键词：花岗岩锆石SHRIMP U-Pb定年双向俯冲北祁连

Bashikaogong-Shimierbulake granitic complex, north Altun, NW China:Geochemistry and zircon SHRIMP ages

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Science China Earth Sciences 2006年第12期49卷 1233-1251页

作者： Joseph L. Wooden frank k. mazdab Stanford University

The Bashikaogong-Shimierbulake granitoid complex is about 30 km long and 2―6 km wide, with an area of 140 km2, located at the north margin of the Bashikaogong Basin in the north Altun terrain. It intruded into schist, metapelite and metatuff of Precambrian ages. This granitoid complex consists of darkish quartz diorite, grey granite, pink granite and pegmatite. Geochemically, the quartz diorite has I-type granite affinity and belongs to Calc-alkaline sereies, and the other gran- ites have S-type affinity and to high-k calc-alkaline series. Zircon SHRIMP U-Pb dating shows that the quartz diorite has a bigger age than those of other granites, which is 481.6±5.6 Ma for quartz diorite, 437.0±3.0 Ma―433.1±3.4 Ma for grey granite and 443±11 Ma―434.6±1.6 Ma for pink granite, re- spectively. Combined with regional geology, we think that the quartz diorite formed in tectonic envi- ronment related to oceanic crust subduction and the granites in post-collision.

关键词： quartz diorite,granite,zircon SHRIMP U-Pb dating,Bashikaogong-Shimierbulake.

Habitat differences in dung beetle assemblages in an African savanna–forest ecotone:implications for secondary seed dispersal

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Integrative Zoology 2011年第2期6卷 81-96页

作者： Britta k.kUNZ frank-Thorsten kRELL Department of Animal Ecology and Tropical Biology Theodor-Boveri Institute of BiosciencesWürzburgGermany Department of Zoology Denver Museum of Nature&ScienceDenverColoradoUSA

The probability and pattern of secondary seed dispersal by dung beetles(Scarabaeinae)depend on their community structure and composition at the site of primary deposition,which,in turn,seem to be strongly determined by ***,we expected pronounced differences in secondary seed dispersal between forest and savanna in the northern Ivory Coast,West *** found 99 dung beetle species at experimentally exposed dung piles of the olive baboon(Papio anubis(Lesson,1827)),an important primary seed disperser in West ***-six species belonged to the roller and tunneler guilds,which are relevant for secondary seed *** species showed a clear habitat *** to the Neotropics,species number and abundance were much higher in the savanna than in the *** and tunnelers each accounted for approximately 50%of the individuals in the savanna,but in the forest rollers made up only 4%.Seeds deposited into the savanna by an omnivorous primary disperser generally have a higher overall probability of being more rapidly dispersed secondarily by dung beetles than seeds in the ***,rollers disperse seeds over larger *** contrast to other studies,small rollers were active in dispersal of large seeds,which were seemingly mistaken for dung *** results suggest that rollers can remove seeds from any plant dispersed in primate dung in this ecosystem.

关键词： Africa baboon defecations guild differences Scarabaeidae secondary seed dispersal.

北阿尔金巴什考供盆地南缘花岗杂岩体特征及锆石SHRIMP定年

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岩石学报 2005年第3期21卷 846-858页

作者：吴才来杨经绥姚尚志曾令森陈松永李海兵戚学祥 Wooden J L mazdab F k 中国地质科学院地质所北京100037 安徽省地质调查院合肥230001 斯坦福大学

北阿尔金巴什考供盆地南缘花岗杂岩体呈近东西向分布,长约49公里,出露面积约90平方公里,与围岩之间为明显的侵入接触关系,接触界线为不规则的渡状、锯齿状。围岩为前寒武纪砂岩、片岩、泥岩及凝灰质砂岩。该杂岩体主要由巨斑花岗岩、红... 详细信息

北阿尔金巴什考供盆地南缘花岗杂岩体呈近东西向分布,长约49公里,出露面积约90平方公里,与围岩之间为明显的侵入接触关系,接触界线为不规则的渡状、锯齿状。围岩为前寒武纪砂岩、片岩、泥岩及凝灰质砂岩。该杂岩体主要由巨斑花岗岩、红色花岗岩、灰白色似斑状花岗岩和粉红色似斑状花岗岩组成。杂岩体的主元素含量变化不大,SiO2为65．14％- 75．66％,全碱含量为7．49-8．96％,k2O／Na2O比值为1．12-2．68,岩石的里特曼指数平均为2．34,CIPW标准矿物计算均出现刚玉(AC)(平均为1．78),说明岩石铝过饱和;杂岩体的稀土总量变化于89．44×10-6-335．28×10-6之间,不同岩石类型均有负铕异常,且从巨斑花岗岩→灰白色似斑状花岗岩→红色似斑状花岗岩→红色花岗岩,负铕异常越来越明显,表现在Eu／ Eu+值由0．65→0．51→0．48→0．30。在微量元素蛛网图上,所有样品的微量元素丰度均高于原始地幔值,并具有相似的配分模式,即在Ba、Nb、Sr、P、Ti处呈明显的低谷,显示出S型花岗岩的特征。锆石SHRIMP U-Pb定年得出,巨斑花岗岩、红色中细粒花岗岩、灰白色和粉红色似斑状花岗岩的年龄分别为474．3±6．8Ma、446．6±5．2Ma、434．5±3．8Ma和431．1±3．8Ma。结合区域地质特征,我们认为,该杂岩体形成于同碰撞-碰撞后的构造环境。

关键词：花岗岩锆石SHRIMP定年巴什考供盆地北阿尔金

From basic properties to the Mott design of correlated delafossites

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npj Computational Materials 2021年第1期7卷 1084-1100页

作者： frank Lechermann European XFEL SchenefeldGermany Center for Computational Quantum Physics Flatiron InstituteNew YorkNYUSA

The natural-heterostructure concept realized in delafossites highlights these layered *** metallic,band-or Mott-insulating character may be associated with individual layers,inter-layer coupling still plays a decisive *** review the correlated electronic structure of PdCoO_(2),PdCrO_(2),and AgCrO_(2),showing that layer-entangled electronic states can deviate from standard classifications of interacting *** finding opens up possibilities for materials design in a subtle Mott-critical *** Hidden-Mott physics,correlation-induced semimetallicity,or Dirac/flat-band dispersions in a Mott background are emerging *** with achievements in the experimental preparation,this inaugurates an exciting research field in the arena of correlated materials.

关键词： materials metallic showing

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

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Optoelectronics Letters 2008年第2期4卷 140-142页

作者： Robert Schmitt Tilo Pfeifer frank Depiereux Niels knig Fraunhofer Institute for Production Technology (IPT) Steinbachstrasse 17 52074 Aachen Germany

Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.

关键词：纤维光干扰术光检测技术测量方法

Computer Forensics-An Essential Element of Modern IT Security

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Journal of Harbin Institute of Technology(New Series) 2014年第6期21卷 5-8页

作者： frank Y.W.Law k.P.Chow Center for Information Security and Cryptography University of Hong Kong

Computer forensics is the science of obtaining,preserving,and documenting evidence from computers,mobile devices as well as other digital electronic storage *** must be done in a manner designed to preserve the probative value of the evidence and to assure its admissibility in a legal ***,computer forensics is continually evolving as existing technologies progress and new technologies are *** example,digital investigators are required to investigate content on mobile device or data stored at the cloud *** the popularity of computers in everyday life as well as the acceleration of cybercrime rates in recent years,computer forensics is becoming an essential element of modern IT *** paper will cover the development of computer forensics in law enforcement and discuss the development in the latest live forensics skillsets.A number of interested areas of computer forensics will be also highlighted to explain how it can support IT security and civil / criminal investigation.

关键词： computer forensics cybercrime digital evidence

Therapeutic targeting of epidermal growth factor receptor in human cancer: successes and limitations

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Chinese Journal of Cancer 2011年第1期30卷 5-12页

作者： Jill Wykosky Tim Fenton frank Furnari Webster k. Cavenee Ludwig Institute for Cancer Research University of California San Diego Department of Medicine University of California San Diego

Epidermal growth fac tor receptor (EGFR) is one of the most commonly altered genes in human cancer by way of over-expression, amplification, and mutation. Targeted inhibition of EGFR activity suppresses signal transduction pathways which control tumor cell growth, proliferation, and resistance to apoptosis. Small molecule tyrosine kinase inhibitors and monoclonal antibodies are among the most common EGFR-targeting agents and have been used clinically for treating various malignancies. This review discusses the successes and challenges of targeting EGFR in human cancer. The genetic alterations of EGFR tend to occur more often in some solid tumors than others, as do the mechanisms of resistance to targeted inhibition. The clinical and basic science experiences with these agents thus far have important implications for the future of therapeutic targeting of EGFR.

关键词：表皮生长因子受体靶向治疗癌症人类酪氨酸激酶抑制剂信号转导通路恶性肿瘤临床治疗

Felsenstein＇s ＂one-allele model＂ of speciation： The role of philopatry in the initial stages of host plant mediated reproductive isolation in Enchenopa binotata

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Current Zoology 2013年第5期59卷 658-666页

作者： frank W. STEARNS kelley J. TILMON Thomas k. WOOD Department of Biology Biology-Psychology Building University of Maryland College Park MD 20742 USA Department of Plant Science Plant Science Building South Dakota State University Brookings SD 57007 USA Department of Entomology and Applied Ecology 250 Townsend Hall University of Delaware Newark DE 19716 USA

The study of speciation genetics is primarily concerned with identifying the genetic traits that allow divergent selec- tion to overcome the homogenizing effects of gene flow. Felsenstein reviewed this race between gene flow and selection, con- cluding that speciation with gene flow was unlikely under a ＂two-allele model＂（where two traits were necessary for reproductive isolation） but that divergence could occur quite easily under a ＂one-allele model.＂ Despite this finding, much of the sympatric speciation research involving phytophagous insects has relied on a two-trait model, where insects evolve both preferences for and increased performance on novel host plants. Philopatry （a tendency to remain where one was born） is known to occur in phyto- phagous insects and is a single trait isolation mechanism. However, it is traditionally invoked as simply augmenting reproductive isolation. Species in the Enchenopa binotata complex are believed to have speciated in sympatry. They exhibit host plant prefe- rences, host specific performance advantages and strong philopatry. We experimentally shifted E. binotata to evolutionarily novel host plants. Previous research has demonstrated that the experimental population of insects possesses genetic variation in prefe- rence and performance to the novel host. The degree of philopatry at mating and egg-laying was assayed for the first four years under full choice conditions. Host plant preference and performance was assayed after eight years. Philopatry was an immediate and strong isolating mechanism, while preference for and performance on the novel host lagged. We therefore suggest that philo- patry may be a more important mechanism in the early stages of a host shift than previously believed [Current Zoology 59 （5）： 658-666, 2013].

关键词： Philopatry Enchenopa Ecological Speciation Sympatric Speciation