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Petrogenesis of Paleoproterozoic Luyashan charnockitic rocks in Shanxi Province: Constraints from Geochemistry and Nd isotope

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Progress in Natural Science:Materials International 2006年第2期16卷 183-191页

作者： liu Chaohui, liu Shuwen, LI Qiugen, WANG Yueran, DANG Qingning, GU Libing, YANG bin and ZHAO Fengsan (Key laboratory of Orogenic Belts and Crustal Evolution, Ministry of Education school of Earth and Space sciences, peking university, beijing 100871, china) Key laboratory of Orogenic Belts and Crustal Evolution Ministry of Education Peking University Beijing 100871 China school of Earth and Space sciences Peking University Beijing 100871 China

Luyashan charnockite pluton mainly consists of monzonite, adamellite, charnockite and syenogranite, which are characterized by the enrichment of TiO2, P2O5, K2O, Zr, Nb, Y, Pb, La, Ce, Ba and a higher K2O/Na2O and depletion of MgO, CaO, Mg#, Th, U and lower Sr/Ba and Rb/Ba. The negative correlations between Zr, Nb, Ce and SiO2 are distinct from I-type granites. Iso-topically Luyashan charnockite plutons are relatively uniform in Nd isotope, displaying initial εNd(t) (-5.93 to -6.97) and Nd depleted mantle model ages (2.67 Ga to 2.78Ga). These features indicate that Luyashan charnockitic magma derived from pre-existing late Archean crustal sources and the partial melting of mafic granulites probably under exceptionally high temperature with CO2-rich fluid. The garnet is a main residual phase during the partial melting. The original dry charnockitic magma experienced crystal fractionation of pyroxene, plagioclase, apatite and ilmenite during early crystallization. The geochemical evidence suggests that the Luyashan charnockitic magma was probably generated in the post-collision thermal relaxation and uplift tectonic setting after the main collision ( - 1850 Ma) between the Eastern and Western continental blocks.

关键词： Luyashan charnockite geochemistry Sm-Nd isotopes petrogenesis Paleoproterozoic.

Quasi-periodic solutions of a semilinear Li(?)nard equation at resonance

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Science china mathematics 2005年第9期 84-94页

作者： liu bin LMAM,school of mathematical sciences,peking university,beijing 100871,china

We are concerned with the existence of quasi-periodic solutions for the follow- ing equation x″+F（x,t）x′+ωx+φ（x,t）=0, where F and φare smooth functions and 2π-periodic in t,ω>0 is a *** some assumptions on the parities of F and φ,we show that the Dancer’s function,which is used to study the existence of periodic solutions,also plays a role for the existence of quasi-periodic solutions and the Lagrangian stability （*** solutions are bounded）.

关键词： quasi-periodic solutions semilinear Liénard equations,boundedness of solutions reversible systems

Nd-Sr Isotopic Geochemistry of the Late Archean-Paleoproterozoic Granitoids in the Lüliang-Wutai Terrain,North china Craton,and Implications for Petrogenesis

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Acta Geologica Sinica(English Edition) 2006年第6期80卷 834-843页

作者： CHEN bin, liu Shuwen, WANG Rui, CHEN Zhichao and liu Chaoqun Key laboratory of Orogenic Belts and Crustal Evolution, MOE school of Earth and Space sciences, peking university, beijing 100871 peking Univ Key Lab Orgen Belts & Crustal Evolut MOE Sch Earth & Space Sci Beijing 100871 Peoples R China

In this paper we report geochemical and Nd-Sr isotopic data for a late Archean gneissic granitic pluton （Hengling pluton）, an early Paleoproterozoic complex （Xipan complex） and a late Paleoproterozoic granitic pluton （Yunzhongshan granites） from the Liiliang-Wutai terrain, North china, to trace the source of these late Archean-Paleoproterozoic granitoids and, particularly, to understand the nature and mechanism of continental growth at that time. The Hengling granitic gneisses （ca. 2.51 Ga） are characterized by high Na2O and LILEs, TTG-like REE patterns （highly depleted HREE and minor Eu anomalies） and moderately depleted Nd-Sr isotopic compositions （εNd（t） =1.2-2.7, ISr=0.7015-0.7019）, and were considered as being products of arc magmatism that was developed upon the North china craton. The Xipan complex （ca. 2.2 Ga） contain gabbroic diorite and monzonite, mostly being Na2O-rich, highly fractionated REE patterns and isotopically enriched （εNd（t） =-1.5 to -4.1, Isr=0.7038-0.706）. The gabbroic diorites probably originated from melting of an enriched mantle source, but significantly contaminated by lower crustal material, and the monzonites probably represent a product of a mixture between the gabbroic dioritic magma and granitic melts of crustal origin. The Yunzhongshan post-collisional granitoids （ca. 1.8 Ga） are characterized by high-K affinity and highly-enriched and homogeneous Nd isotopic compositions （εNd（t）=-4.9 to -5.7）, although they split into two groups in terms of REE patterns： one group showing elevated HREE （and Sc, Y and Zr） with significant negative Eu anomalies and the other showing highly depleted HREE and, to a lesser extent, mid-REE with negligible Eu anomalies. These granites are genetically related to a process of extensional collapse of a thickened orogen. They formed through magma mixing between mantle-derived basaltic magmas and crust-derived granitic melts, followed by significant fractionation of ferromagnesian phases （like hornblende and C

关键词： geochemistry Nd-Sr isotopes granitoids late Archean-Paleoproterozoic Wutai-Lüliang

Docking protein 6 (DOK6) selectively docks the neurotrophic signaling transduction to restrain peripheral neuropathy

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Signal Transduction and Targeted Therapy 2024年第3期9卷 1147-1164页

作者： Yan Guo Pan Xiang Xiaojiao Sun Wei liu Jiafeng Zhou bin Yin Lin Hou Boqin Qiang Huiliang Li Pengcheng Shu Xiaozhong Peng Department of Molecular Biology and Biochemistry Institute of Basic Medical SciencesMedical Primate Research CenterNeuroscience CenterChinese Academy of Medical SciencesSchool of Basic Medicine Peking Union Medical CollegeBeijingChina State Key laboratory of Common Mechanism Research for Major Diseases Beijing 100005China Wolfson Institute for Biomedical Research University College LondonGower StreetLondon WC1E 6BTUK Chinese Institute for Brain Research Beijing 102206China State Key laboratory of Respiratory Health and Multimorbidity Beijing 100005China Institute of laboratory Animal Science Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100021China

The appropriate and specific response of nerve cells to various external cues is essential for the establishment and maintenance of neural circuits,and this process requires the proper recruitment of adaptor molecules to selectively activate downstream ***,we identified that DOK6,a member of the Dok(downstream of tyrosine kinases)family,is required for the maintenance of peripheral axons,and that loss of Dok6 can cause typical peripheral neuropathy symptoms in mice,manifested as impaired sensory,abnormal posture,paw deformities,blocked nerve conduction,and ***,Dok6 is highly expressed in peripheral neurons but not in Schwann cells,and genetic deletion of Dok6 in peripheral neurons led to typical peripheral myelin outfolding,axon destruction,and hindered retrograde axonal ***,DOK6 acts as an adaptor protein for selectivitymediated neurotrophic signal transduction and retrograde transport for TrkC and Ret but not for TrkA and ***6 interacts with certain proteins in the trafficking machinery and controls their phosphorylation,including MAP1B,Tau and Dynein for axonal transport,and specifically activates the downstream ERK1/2 kinase pathway to maintain axonal survival and *** finding provides new clues to potential insights into the pathogenesis and treatment of hereditary peripheral neuropathies and other degenerative diseases.

关键词： impaired restrain peripheral

A review on flexible solar cells

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Science china Materials 2024年第9期67卷 2717-2736页

作者： Shenglei Huang Cheng Qian Xingting liu Liping Zhang Fanying Meng Zhu Yan Yinuo Zhou Junlin Du bin Ding Jianhua Shi Anjun Han Wenjie Zhao Jian Yu Xin Song Zhengxin liu Wenzhu liu Research Center for New Energy Technology(RCNET) National Key Laboratory of Materials for Integrated CircuitsShanghai Institute of Microsystem and Information Technology(SIMIT)Chinese Academy of Sciences(CAS)Shanghai 201800China school of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China university of Chinese Academy of sciences(UCAS) Beijing 100049China school of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China school of Materials Science and Engineering Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and ApplicationsChangzhou UniversityChangzhou 213164China Institute of Solid Mechanics Beihang UniversityBeijing 100191China

With the gradual progression of the carbon neutrality target,the future of our electricity supply will experience a massive increase in solar generation,and approximately 50%of the global electricity generation will come from solar generation by *** provides the opportunity for researchers to diversify the applications of photovoltaics(PVs)and integrate for daily use in the *** solar cell technology is the next frontier in solar PV and is the key way to achieve CO_(2)*** integration of PV technology with other fields will greatly broaden the development areas for the PV industry,providing products with higher added *** this paper,we reviewed the latest research progress on flexible solar cells(perovskite solar cells,organic solar cells,and flexible silicon solar cells),and proposed the future applications of flexible solar cell technology.

关键词： carbon neutrality flexible PVs perovskite solar cells organic solar cells flexible silicon solar cells

Towards growth of pure AB-stacked bilayer graphene single crystals

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Nano Research 2024年第5期17卷 4616-4621页

作者： Xiaowen Zhang Tao Zhou Yunlong Ren Zuo Feng Ruixi Qiao Qinghe Wang bin Wang Jinxia Bai Muhong Wu Zhilie Tang Xu Zhou Kaihui liu Xiaozhi Xu Guangdong Basic Research Center of Excellence for Structure and Fundamental Interactions of Matter Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum MaterialsSchool of PhysicsSouth China Normal UniversityGuangzhou 510006China Guangdong-Hong Kong Joint laboratory of Quantum Matter School of PhysicsSouth China Normal UniversityGuangzhou 510006China Physical Science and Engineering Division King Abdullah University of Science and TechnologyThuwal 23955–6900Saudi Arabia State Key laboratory for Mesoscopic Physics Frontiers Science Center for Nano-optoelectronicsSchool of PhysicsPeking UniversityBeijing 100871China Institute for Frontier Science Nanjing University of Aeronautics and AstronauticsNanjing 210094China International Centre for Quantum Materials Collaborative Innovation Centre of Quantum MatterPeking UniversityBeijing 100871China Songshan Lake Materials laboratory Institute of PhysicsChinese Academy of SciencesDongguan 523808China

Given its intriguing band structure and unique tunable bandgap,AB-stacked bilayer graphene has great potentials in the applications of high-end electronics,optoelectronics and *** epitaxial growth of AB-stacked single-crystal bilayer graphene films requires a strict AB-stacked lattice,identical orientations and seamless stitching of bilayer graphene ***,the particles inevitably present on the metal surface that produced during high temperature growth would induce random orientations,twisted stacking islands,and uncontrollable multilayers,which is a great challenge to ***,we propose a heat-resisting-box assisted strategy to produce nearly pure AB-stacked bilayer graphene single-crystal films on Cu/Ni(111)*** our technique,the particles on the Cu/Ni(111)surface are effectively eliminated,which greatly minimizes the occurrence of randomly twisted islands and uncontrollable *** as-grown AB-stacked bilayer graphene films show>99%alignment and>99%AB stacking *** work provides a promising method towards the growth of pure AB-stacked bilayer graphene single crystals and would accelerate its device applications.

关键词： bilayer graphene AB stacking uniform growth heat-resisting box

Promoting interactions between cognitive science and large language models

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The Innovation 2024年第2期5卷 9-10页

作者： Youzhi Qu Penghui Du Wenxin Che Chen Wei Chi Zhang Wanli Ouyang Yatao Bian Feiyang Xu bin Hu Kai Du Haiyan Wu Jia liu Quanying liu Department of Biomedical Engineering Southern University of Science and TechnologyShenzhen 518055China Shanghai AI laboratory Shanghai 200232China Tencent AI Lab Shenzhen 518057China iFLYTEK AI Research Hefei 230088China school of Medical Technology Beijing Institute of TechnologyBeijing 100081China Institute for Artificial Intelligence Peking UniversityBeijing 100871China Centre for Cognitive and Brain sciences and Department of Psychology University of MacaoMacao 999078China Department of Psychology Tsinghua UniversityBeijing 100084China

Large language models(LLMs)have made unprecedented progress,demonstrating human-like language proficiency and an extraordinary ability to encode complex *** emergence of high-level cognitive capabilities in LLMs,such as in-context learning and complex reasoning,suggests a path toward the realization of artificial general intelligence(AGI).However,we lack scientific theories and tools to assess and interpret such an emergence of the advanced intelligence of *** intelligence(AI)has been extensively applied in various areas of fundamental science to accelerate scientific research.

关键词： cognitive such language

Studies on wind environment around high buildings in urban areas

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Science china Earth sciences 2005年第Z2期48卷 102-115页

作者： liu Huizhi, JIANG Yujun, LIANG bin, ZHU Fengrong, ZHANG Boyin & SANG Jianguo LAPC, Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 100029, china Department of Atmospheric sciences, school of Physics, peking university, beijing 1000871, china State Key laboratory of Turbulence and Complex System, peking university, beijing 1000871, china LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Department of Atmospheric sciences School of Physics Peking University Beijing 1000871 China State Key laboratory of Turbulence and Complex System Peking University Beijing 1000871 China

High buildings or architectural complex in urban areas remarkably distort the urban surface wind fields. As the air flow approaches,local strong wind may appear around the buildings. The strong wind makes the pedestrians on sidewalks, entrances and terrace very uncomfortable and causes the pedestrian level wind environment problem. In this studies, hot-wire wind measurement, wind scouring in wind tunnel and numerical computation were carried out to evaluate the wind environment of tall buildings in the prevailing flow conditions in beijing areas. The results obtained by three techniques were compared and mutually verified. The conclusions drawn from three approaches agree with each other. Also the advantages and limitations of each method were analyzed. It is suggested that the combination of different techniques may produce better assessment of wind environment around high buildings.

关键词： high buildings in urban areas, wind environment, wind tunnel, numerical simulation.

Late Paleoproterozoic Geodynamic Transition of the Central Tectonic Zone, North china Craton: Constraints from the geochemistry of granitoids in Lüliangshan Precambrian block

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Late Paleoproterozoic Geodynamic Transition of the Central T...