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青藏高原北缘伸展构造对金矿形成的控制作用及其成矿时代探讨

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矿床地质 2002年第S1期21卷 97-100页

作者：陈宣华杨风 george e.gehrels 王小凤陈柏林陈正乐杨懿李学智中国地质科学院地质力学研究所北京100081 新疆地质调查院一所新疆乌鲁木齐830011 Department of Geosciences University of Arizona

青藏高原北缘阿尔金山东北段大平沟金矿床是受eW向伸展构造(拉配泉正断层)控制的韧性剪切带型金矿床。本文阐明了大平沟金矿床地质特征和矿床成因,并利用锆石TIMS法和离子探针U-Pb定年方法、40Ar/39Ar阶段加温测年和MDD模拟方法,分析了... 详细信息

青藏高原北缘阿尔金山东北段大平沟金矿床是受eW向伸展构造(拉配泉正断层)控制的韧性剪切带型金矿床。本文阐明了大平沟金矿床地质特征和矿床成因,并利用锆石TIMS法和离子探针U-Pb定年方法、40Ar/39Ar阶段加温测年和MDD模拟方法,分析了与金矿床有关的岩浆作用和伸展构造的活动时代。结果表明,与大平沟金矿床有关的花岗岩浆活动的时代为早奥陶世(485Ma),而金矿床的控矿构造(拉配泉正断层)的活动时代为早侏罗世(200～187Ma期间)。由此可见早古生代岩浆活动为青藏高原北缘的金矿化提供了物质来源,而中生代伸展作用直接控制了金矿化,金的成矿时代为早侏罗世。

关键词：伸展作用金矿床成矿时代青藏高原北缘

青藏高原北缘中生代伸展构造^(40)Ar/^(39)Ar测年和MDD模拟

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地球学报 2002年第4期23卷 305-310页

作者：陈宣华尹安 george e.gehrels 王小凤 eric S.Cowgill Marty Grove T.Mark Harrison 陈正乐中国地质科学院地质力学研究所北京100081 Department of earth and Space Sciences and Institute of Geophysics and Planetary Physics University of California Department of Geosciences University of Arizona

沿着青藏高原北缘的阿尔金山脉东段 ,发育了长度大于 30 0km、eW走向的拉配泉断裂。中美合作阿尔金课题组的地质填图结果表明 ,该断层实际上是一条南倾的正断层 ,局部倾角可以低至 30°以下。沉积学和热年代学研究控制了拉配泉断裂的活... 详细信息

沿着青藏高原北缘的阿尔金山脉东段 ,发育了长度大于 30 0km、eW走向的拉配泉断裂。中美合作阿尔金课题组的地质填图结果表明 ,该断层实际上是一条南倾的正断层 ,局部倾角可以低至 30°以下。沉积学和热年代学研究控制了拉配泉断裂的活动时代 :早—中侏罗统地层可以解释为断裂上盘的伸展盆地沉积 ;下盘岩石中钾长石40 Ar/ 3 9Ar测年和MDD模拟给出 2个阶段的冷却事件 ,早期事件出现在约 2 2 0～ 187Ma之间 ,晚期事件出现在早白垩世晚期 (约 10 0Ma)。早期事件代表了拉配泉断裂正断作用的主要阶段。

关键词：青藏高原阿尔金山拉配泉断裂 ^40Ar/^39Ar测年 MDD模拟氩同位素中生代

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阿尔金山区域热演化历史的初步研究

地质论评 2002年第S1期48卷 146-152页

作者：陈宣华尹安高荐 george e.gehrels 陈正乐王小凤 eric S.COWGILL Marty GROVe T.Mark HARRISON 中国地质科学院地质力学研究所北京100081 Department of earth and Space Sciences and Institute of Geophysics and Planetary Physics University of California 中国石油股份公司青海油田分公司甘肃敦煌736202 Department of Geosciences University of Arizona Department of earth and Space Sciences and Institute of Geophysics and Planetary Physics

通过地质年龄数据的综合分析,本文探讨了阿尔金山地区自元古宙以来的区域热演化历史。其中,本区自古太古代以来具有多期岩浆活动,其主要活动时期为早古生代晚期(490～385 Ma),高峰期年龄为442Ma左右。同时,具有新元古代、早古生代、中... 详细信息

通过地质年龄数据的综合分析,本文探讨了阿尔金山地区自元古宙以来的区域热演化历史。其中,本区自古太古代以来具有多期岩浆活动,其主要活动时期为早古生代晚期(490～385 Ma),高峰期年龄为442Ma左右。同时,具有新元古代、早古生代、中生代和新生代4次地壳抬升和冷却事件。其中中生代冷却事件启动时间与阿尔金北缘伸展作用早期活动时间相一致;新生代事件出现在7 Ma左右,与青藏高原隆升具有密切关系。

关键词：阿尔金山热年代学演化阶段

Flexible ultra-thin super-resolution endoscopy

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Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 171-172页

作者： george S.D.Gordon Department of electrical and electronic engineering University of NottinghamNottingham NG7 2RDUK

In recent years, multimode fiber(MMF) has become an important tool for high-resolution endoscopic imaging in narrow channels(e.g., in the brain via needles or inside blood vessels) due to its high mode density and fine diameter, typically ever, a major obstacle to widespread deployment in applications is that realistic perturbations, including bending, twisting and changes in temperature, cause unacceptable image degradation.

关键词： fiber resolution typically

Bulk geochemistry,Rb-Sr,Sm-Nd,and stable O-H isotope systematics of the Metzimevin high-grade iron ore deposit,Mbalam iron ore district,southern Cameroon

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Acta Geochimica 2024年第4期43卷 677-706页

作者： Samndong Cyril Tufoin Cheo emmanuel Suh Tabod Charles Tabod george Lemewihbwen Ngiamte Department of Geology Mining and Environmental ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon economic Geology Unit Department of GeologyUniversity of BueaP.O.63BueaSouth West RegionCameroon Department of Physics Faculty of ScienceThe University of BamendaB.P.39BambiliNorth West RegionCameroon Department of Geology Pan-African University Life and Earth Sciences Institute(PAULESI)University of IbadanIbadanNigeria

Bulk geochemistry,Sr,Nd,and O-H isotope systematics are reported for the first time on banded iron formation(BIF)-hosted high-grade iron ore at the northwestern segment of Congo Craton(CC).Located in Mbalam iron ore district,Southern Cameroon,Metzimevin iron ore deposit is a hematite-magnetite BIF system,dominated by SiO_(2)+Fe_(2)O_(3)(97.1 to 99.84 wt%),with low concentrations of clastic elements e.g.,Al_(2)O_(3),TiO_(2),and HFSe,depicting a nearly pure chemical *** Ree+Y signature of the iron deposit displays strong positive eu anomaly,strong negative Ce anomaly,and chondritic to superchondritic Y/Ho ratios,suggestive of formation by mixed seawater-high temperature hydrothermal fluids in oxidising ***^(87)Sr/^(86)Sr ratios of the BIF are higher than the maximum^(87)Sr/^(86)Sr evolution curves for all Archean reservoirs(bulk silicate earth,Archean crust and Archean seawater),indicating involvement of continentally-derived components during BIF formation and ***Ɛ_(Nd)(t)(+2.26 to+3.77)and Nd model age indicate that chemical constituents for the BIF were derived from undifferentiated crustal source,between 3.002 and 2.88 *** variable and diverse O and H isotope data(−1.9‰to 17.3‰and−57‰to 136‰respectively)indicate that the Metzimevin iron ore formed initially from magmatic plumes and later enriched by magmatic-metamorphic-modified meteoric *** balance calculations indicate mineralisation by combined leaching and precipitation,with an average iron enrichment factor of>2.67 and SiO_(2)depletion factor of>*** is associated with an overall volume reduction of 28.27%,reflecting net leaching and volume collapse of the BIF protholith.

关键词： Bulk geochemistry Rb-Sr Sm-Nd Mitzimevin High-grade iron ore

Multifunctional nanoparticle-mediated combining therapy for human diseases

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Signal Transduction and Targeted Therapy 2024年第2期9卷 343-375页

作者： Xiaotong Li Xiuju Peng Makhloufi Zoulikha george Frimpong Boafo Kosheli Thapa Magar Yanmin Ju Wei He School of Pharmacy China Pharmaceutical UniversityNanjing 2111198PR China Xiangya School of Pharmaceutical Sciences Central South UniversityChangsha 410013PR China Shanghai Skin Disease Hospital Tongji University School of MedicineShanghai 200443China

Combining existing drug therapy is essential in developing new therapeutic agents in disease prevention and *** preclinical investigations,combined effect of certain known drugs has been well established in treating extensive human *** to synergistic effects by targeting various disease pathways and advantages,such as reduced administration dose,decreased toxicity,and alleviated drug resistance,combinatorial treatment is now being pursued by delivering therapeutic agents to combat major clinical illnesses,such as cancer,atherosclerosis,pulmonary hypertension,myocarditis,rheumatoid arthritis,inflammatory bowel disease,metabolic disorders and neurodegenerative *** therapy involves combining or co-delivering two or more drugs for treating a specific ***(NP)-mediated drug delivery systems,i.e.,liposomal NPs,polymeric NPs and nanocrystals,are of great interest in combinatorial therapy for a wide range of disorders due to targeted drug delivery,extended drug release,and higher drug stability to avoid rapid clearance at infected *** review summarizes various targets of diseases,preclinical or clinically approved drug combinations and the development of multifunctional NPs for combining therapy and emphasizes combinatorial therapeutic strategies based on drug delivery for treating severe clinical ***,we discuss the challenging of developing NP-codelivery and translation and provide potential approaches to address the *** review offers a comprehensive overview for recent cutting-edge and challenging in developing NP-mediated combination therapy for human diseases.

关键词： drugs diseases prevention

A Literature Review: Potential effects That Health Apps on Mobile Devices May Have on Patient Privacy and Confidentiality

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e-Health Telecommunication Systems and Networks 2024年第3期13卷 23-44页

作者： Anna Sheri george Jomin george Judy Jenkins Faculty of Medicine and Health Life Sciences Swansea University Swansea UK

Purpose: This research aims to evaluate the potential threats to patient privacy and confidentiality posed by mHealth applications on mobile devices. Methodology: A comprehensive literature review was conducted, selecting eighty-eight articles published over the past fifteen years. The study assessed data gathering and storage practices, regulatory adherence, legal structures, consent procedures, user education, and strategies to mitigate risks. Results: The findings reveal significant advancements in technologies designed to safeguard privacy and facilitate the widespread use of mHealth apps. However, persistent ethical issues related to privacy remain largely unchanged despite these technological strides.

关键词： Mobile Devices Patient Privacy Confidentiality Breaches Data Security Data Protection Regulatory Compliance User Consent Data encryption Third-Party Integration User Awareness

A Revealing Voyage Visit to China dispels misperceptions,shows the real picture of China-Africa friendship

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ChinAfrica 2024年第9期16卷 62-63页

作者： george MUSIIMe Development Watch Centre Nigeria

It is very easy for an African living in Africa to be misled into believing that the China-Africa friendship is *** fact,with so much of information reaching Africa about China-Africa cooperation being targeted at undermining the friendly relations enjoyed by the two sides and the e!orts to build a China-Africa community with a shared future,this in a way is not surprising.

关键词： Africa superficial friends

Paleozoic and Mesozoic Basement Magmatisms of eastern Qaidam Basin,Northern Qinghai-Tibet Plateau:LA-ICP-MS Zircon U-Pb Geochronology and its Geological Significance

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Acta Geologica Sinica(english edition) 2012年第2期86卷 350-369页

作者： CHeN Xuanhua George.gehrels YIN An LI Li JIANG Rongbao Key Laboratory of Neotectonic Movement and Geohazard Ministry of Land and ResourcesBeijing 100081China Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Department of Geosciences University of ArizonaTucsonAZ 85721USA Department of earth andSpace Sciences University of CaliforniaLos AngelesCA 90095-1567USA

The eastern margin of the Qaidam Basin lies in the key tectonic location connecting the Qinling, Qilian and east Kunlun orogens. The paper presents an investigation and analysis of the geologic structures of the area and LA-ICP MS zircon U-Pb dating of Paleozoic and Mesozoic magmatisms of granitoids in the basement of the eastern Qaidam Basin on the basis of 16 granitoid samples collected from the South Qilian Mountains, the Qaidam Basin basement and the east Kunlun Mountains. According to the results in this paper, the basement of the basin, from the northern margin of the Qaidam Basin to the east Kunlun Mountains, has experienced at least three periods of intrusive activities of granitoids since the early Paleozoic, i.e. the magmatisms occurring in the Late Cambrian （493.1±4.9 Ma）, the Silurian （422.9±8.0 Ma-420.4±4.6 Ma） and the Late Permian-Middle Triassic （257.8±4.0 Ma-228.8＋1.5 Ma）, respectively. Among them, the Late Permian - Middle Triassic granitoids form the main components of the basement of the basin. The statistics of dated zircons in this paper shows the intrusive magmatic activities in the basement of the basin have three peak ages of 244 Ma （main）, 418 Ma, and 493 Ma respectively. The dating results reveal that the early Paleozoic magmatism of granitoids mainly occurred on the northern margin of the Qaidam Basin and the southern margin of the Qilian Mountains, with only weak indications in the east Kunlun Mountains. However, the distribution of Permo-Triassic （P-T） granitoids occupied across the whole basement of the eastern Qaidam Basin from the southern margin of the Qilian Mountains to the east Kunlun Mountains. An integrated analysis of the age distribution of P-T granitoids in the Qaidam Basin and its surrounding mountains shows that the earliest P-T magmatism （293.6-270 Ma） occurred in the northwestern part of the basin and expanded eastwards and southwards, resulting in the P-T intrusive magmatism that ran through the whole basin basement. As

关键词： LA-ICP MS zircon U-Pb dating thrust fault system crust shortening and deformation Paleozoic and Mesozoic magmatism Qinling-Qilian-Kunlun joint zone Qaidam Basin