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Fair E-Payment Protocol Based on Simple Partially Blind Signature Scheme

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Wuhan University Journal of Natural Sciences 2007年第1期12卷 181-184页

作者： LIU Jingwei sun Rong KOU weidong State Key Laboratory of Integrated Service Networks XidianUniversity Xi＇an 710071 Shaanxi China

This paper presents a simple partially blind signature scheme with low computation. By converse using the partially blind signature scheme, we build a simple fair e-payment protocol. In the protocol, two participants achieve the goals of exchanging their digital signatures from each other in a simple way. An ado vantage of this scheme is that this approach does not require the intervention of the third party in any case. The low-computation property makes our scheme very attractive for mobile client and smart-card implementation in many e-commerce applications.

关键词： electronic commerce e-payment Schnorr signature partial blind signature

Coupled Fe–S isotope composition of sulfide chimneys dominated by temperature heterogeneity in seafloor hydrothermal systems

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Science Bulletin 2020年第20期65卷 1767-1774,M0004页

作者： Shujie Wang weidong sun Jing Huang Shikui Zhai Huaiming Li Center of Deep Sea Research Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China Key Lab of Submarine Geosciences and Prospecting Techniques Ministry of EducationCollege of Marine GeosciencesOcean University of ChinaQingdao 26610OChina Key Laboratory of Submarine Geosciences Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China

Seafloor hydrothermal chimneys are significant metal resources and have fundamental effects on marine chemistry *** studies on growth of the chimneys focused on mineral composition and elemental distribution in chimney walls,but the isotopic composition of different elements and their correlations remain poorly ***,we report lateral Fe and S isotopes from sulfides across a chimney wall in detail from the Deyin-1 hydrothermal field(DHF) on the South Mid-Atlantic *** was characterized by increases in both δ34S and δ56Fe from the exterior to the interior within the chimney wall,which is likely related to enhanced S and Fe isotope fractionation between pyrite and fluids derived from the temperature ***,δ56Fe displayed a well-defined,linear,positive correlation with δ34S in pyrite from the DHF as well as in pyrite from other areas.A model of hydrothermal pyrite formation suggests that,under conditions with uniform hydrothermal fluid,different temperatures and similar pyrite-fluid exchange degrees could result in the observed linear relationships between δ34S and δ*** regular and coupled Fe-S isotope variations within the chimney wall efficiently constrain the process of hydrothermal sulfide formation.

关键词： Sulfide chimney Iron isotope Sulfur isotope Temperature

Geochemical and Zircon Hf-O Isotopic Constraints on the Origin of Wulian A-Type Granite in Shandong Peninsula,Eastern China

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Journal of Earth Science 2022年第3期33卷 609-622页

作者： Shuai Yuan He Li Lipeng Zhang Congying Li Haiyang Liu Ying-Yu Xue weidong sun Center of Deep Sea Research Institute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China School of Marine Sciences University of Chinese Academy of SciencesBeijing 100049China

Early Cretaceous A-type granitic plutons are widely distributed in Shandong Peninsula,which are of great significance to understanding the regional tectonic *** we report geochemical characteristics,geochronological results,and zircon Hf-O isotope compositions of Wulian granites to reveal its origin and geological *** granites share most characteristics of the A_(2)-type *** U-Pb LA-ICPMS analysis for Wulian A-type granites yields average age of 116.6±2.1 *** O isotope values range from 4.20‰to 5.57‰,and these values are marginally identical to or slightly lower than those of mantle zircon(5.3‰±0.3‰).Zirconε_(Hf)(t)values(-26.1--23.5)indicate an enriched *** zircon Hf-O isotope compositions indicate that the source region of Wulian granites involves the components of ancient oceanic *** from Wulian granites have the lower chlorine(0.06 wt.%-0.15 wt.%)and higher fluorine contents(2.11 wt.%-2.48 wt.%)compared with Haiyang pluton,together with their high(La/Gd)_(N),(La/Yd)_(N) and low(Gd/Yb)_(N) ratios and high oxygen state magma reflected from zircon,signifying that slab derived component was added into the overlying mantle region through fluid/*** geochemical characteristics of Wulian granites could be explained by the ridge(between the Izanagi and Pacific plates)subduction model,which began to influence the tectonic evolution of the Xuhuai region and Shandong Peninsula since~130±5 *** following slab window between two plates plausibly explains regional extension,resulting in hot magma upwelling and the formation of the A-type granite *** the Lower Yangtze River belt and Shandong Peninsula A-type granite proves the northward movement of the ridge between the Pacific Plate and Izanagi Plate.

关键词： A-type granite Shandong Peninsula ridge subduction zircon Hf-O isotope magma

Ridge subduction and porphyry copper-gold mineralization:An overview

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Science China Earth Sciences 2010年第4期53卷 475-484页

作者： sun weidong LING MingXing YANG XiaoYong FAN WeiMing DING Xing LIANG HuaYing CAS Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Research Center for Mineral Resources School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Graduate University of Chinese Academy of Sciences Beijing 100049China Key Laboratory for Metallogenic Dynamics Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Many large porphyry Cu-Au deposits are connected to adakitic rocks known to be closely associated with ridge subduction. For example, there are several subducting ridges along the east Pacific margin, e.g., in Chile, Peru, and South America, most of which are associated with large porphyry Cu-Au deposits. In contrast, there are much fewer ridge subductions on the west Pacific margin and porphyry Cu-Au deposits are much less there, both in terms of tonnage and the number of deposits. Given that Cu and Au are moderately incompatible elements, oceanic crust has much higher Cu-Au concentrations than the mantle and the continental crust, and thus slab melts with their diagnostic adakitic chemistry have systematically higher Cu and Au, which is favorable for mineralization. Considering the geotherm of subducting slabs in the Phanerozoic, ridge subduction is the most favorable tectonic setting for this. Therefore, slab melting is the likely link in the spatial association between ridge subduction and Cu-Au deposits. Geochemical signatures of slab melting and hence maybe ridge subduction in less eroded regions in eastern China, the central Asian orogenic belt etc. may indicate important exploration targets for large porphyry Cu-Au deposits.

关键词： ridge subduction porphyry Cu-Au deposits adakite slab melting

Chemical Composition of the Primitive Mantle Source of Peridotite Inclusions at Mount Lianshan, Liuhe County,Jiangsu Province

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Acta Geologica Sinica(English Edition) 1998年第2期72卷 180-190页

作者： sun weidong PENG Zicheng CHEN Daogong ZHI Xiachen WANG Zhaorong GE Ningjie Department of Earth&Space Sciences University of Science&Technology of China Advanced Centre for Earth Sciences&Astronomy The Third World Academy of SciencesHefeiAnhui Province 230026

: This paper presents a study of the major and trace element compositions of fresh mantle-derived spinel lherzolite and harzburgite inclusions from Cenozoic alkaline basalt in Mount Lianshan and Mount Panshi, Liuhe County, Jiangsu Province. An estimation is made of the contents of the major elements and some of the trace elements in the primitive mantle source region of the area, from which the authors have obtained MgO/Al2O3= 7.86. The contents of MgO and Al2O3 are also obtained as 37.58% and 4.78% respectively based on the correlation of MgO-Al2O3. Then, the contents of various elements in the primitive mantle are calculated using their regression equations with MgO, and the compositon of the primitive mantle, a basic issue in geochemistry study, is discussed on that basis.

关键词： Mount Lianshan peridotite inclusions mantle source composition of the primitive mantle

Accuracy of LA-ICPMS zircon U-Pb age determination:An inter-laboratory comparison

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Science China Earth Sciences 2015年第9期58卷 1722-1730页

作者： LI XianHua LIU XiaoMing LIU YongSheng SU Li sun weidong HUANG HuiQing YI Keewook State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences State Key Laboratory of Continental Dynamics Department of Geology Northwest University State Key Laboratory of Geological Processes and Mineral Resources Faculty of Earth Sciences China University of Geosciences Geological Lab Center China University of GeosciencesBeijing State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences NSW Institute of Frontiers Geoscience School of Environmental and Life Sciences University of Newcastle University Drive Korea Basic Science Institute

LA-ICPMS zircon U-Pb dating has been greatly advanced and widely applied in the past decade because it is a cheap and fast *** internal error of LA-ICPMS zircon U-Pb dating can be better than 1%,but reproducibility(accuracy)is relatively *** order to quantitatively assess the accuracy of this technique,zircons from two dioritic rocks,a Mesozoic dioritic microgranular enclave(FS06)and a Neoproterozoic diorite(WC09-32),were dated independently in eight laboratories using SIMS and *** of three SIMS analyses on FS06 and WC09-2 are indistinguishable within error and give a best estimate of the crystallization age of 132.2 and 760.5 Ma(reproducibility is^1%,2RSD),*** U-Pb ages determined by LA-ICPMS in six laboratories vary from 128.3±1.0 to 135.0±0.9 Ma(2SE)for FS06 and from 742.9±3.1 to777.8±4.7 Ma(2SE)for WC09-32,suggesting a reproducibility of^4%(2RSD).Uncertainty produced during LA-ICPMS zircon U-Pb analyses comes from multiple sources,including uncertainty in the isotopic ratio measurements,uncertainty in the fractionation factor calculation using an external standard,uncertainty in the age determination as a result of common lead correction,age uncertainty of the external standards and uncertainty in the data *** of our study suggests that the uncertainty of LA-ICPMS zircon U-Pb dating is approximately 4%(2RSD).The uncertainty in age determination must be considered in order to interpret LA-ICPMS zircon U-Pb data rationally.

关键词： zircon U-Pb dating Laser ablation-inductively coupled plasma mass spectrometry (LA-ICPMS) Secondary ion massspectrometry (SIMS) accuracy precision

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步态周期中“8”字绷带外固定对微创治疗拇外翻术后截骨端动态稳定性的有限元分析

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中国医疗设备 2024年第8期39卷 11-19页

作者：曹旭含熊冰朗孙承颐孙旭东郭紫嫣温建民孙卫东中国中医科学院望京医院骨关节二科北京100102 北京中医药大学针灸推拿学院北京100105

目的建立中西医结合微创技术拇外翻足底压力生物力学模型,研究“8”字绷带外固定系统在拇外翻足术后动态力学环境中的足底应力力学数据分布特点及其生物力学规律。方法将同步的三维运动测试与地面垂直反力相应的时相结合,获得足部3个不... 详细信息

目的建立中西医结合微创技术拇外翻足底压力生物力学模型,研究“8”字绷带外固定系统在拇外翻足术后动态力学环境中的足底应力力学数据分布特点及其生物力学规律。方法将同步的三维运动测试与地面垂直反力相应的时相结合,获得足部3个不同的角度,并对术后足踝部分在步行状态下的受力情况进行模拟。在微创治疗拇外翻术后“8”字绷带外固定有限元模型中实施加载及约束,对步行周期状态过程中各个工况时期位移及截骨端用力的情况进行计算(足跟着地时期、支撑时期、加速蹬离时期),进而对该手术步态周期中固定截骨及移位端应力的不断变化进行探究。结果中足跟着地期工况,第一跖骨截骨端最大总应力为0.118 MPa,第一主应力位于Z轴方向,为-0.116620 MPa;截骨端的最大总位移为0.447 mm,最大位移发生在X轴上,为-0.446 mm,位移方向与X轴相反,提示向外侧移位。加速蹬离期工况,截骨端最大总应力为1.485 MPa,第一主应力为-1.467620 MPa;截骨端的最大总位移为1.667 mm,最大位移发生在X轴上,为-1.658 mm。全足支撑期工况与蹬离期方向相同,数值次之。结论在步态周期中,第一跖骨截骨端所受应力以压应力为主,位移主要是截骨远端向外侧移位。术后“8”字绷带外固定能够保证步态周期中微创治疗拇外翻术后截骨端的动态稳定,增加截骨端压应力,促进截骨端愈合。

关键词：拇外翻步态周期有限元绷带外固定截骨端动态稳定性

Os isotopic composition of the earth's primitive upper mantle

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Chinese Science Bulletin 1998年第18期43卷 1575-1579页

作者： weidong sun Xiachen Zhi Zicheng Peng Zhaorong Wang Ningjie Ge Xinhua Zhou Department of Earth and Space Sciences University of Science and Technology of China Hefei China Advanced Research Center on Earth Sciences and Astronomy University of Science and Technology of China Third World Academy of Sciences Hefei China Laboratory of Lithosphere Tectonic Evolution Institute of Geology Chinese Academy of Sciences Beijing China

The osmium isotopic ratio of 187Os/ 188Os ranging from 0.126 to 0.127 for the primitive upper mantle (PUM) is obtained according to the correlation between 187Os/ 188Os and Al 2O 3 of mantle-derived xenoliths and orogenic peridotites, which consists with Allegre and Luck’s ALM value and similar to Yin’s nuggets uniform reservoir (NUR) value. It shows that the Os isotope ratio is lower than enstatite or ondinary chondrites, similar to carbonaceous chondrites (CV3).

关键词： primitive upper mantle Os isotope mantle_derived peridotite.

Geochemistry of subducted metabasites exhumed from the Mariana forearc:Implications for Pacific seamount subduction

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Geoscience Frontiers 2021年第3期12卷 358-369页

作者： Jianghong Deng Lipeng Zhang He Liu Haiyang Liu Renqiang Liao Abdul Shakoor Mastoi Xiaoyong Yang weidong sun Center of Deep Sea Research Institute of OceanologyCenter for Ocean Mega-ScienceChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266237China CAS Key Laboratory of Crust-Mantle Materials and Environments University of Science and Technology of ChinaHefei 230026China University of Chinese Academy of Sciences Beijing 100049China Centre for Pure and Applied Geology University of SindhJamshoro 76080Pakistan

Seamounts on the drifting oceanic crust are inevitably carried by plate motions and eventually accreted or ***,the geochemical signatures of the subducted seamounts and the significance of seamount subduction are not well *** of seamounts have subducted beneath the Philippine Sea Plate following the westward subduction of the Pacific Plate since the Eocene(~52 Ma).The subducted oceanic crust and seamount materials can be exhumed from the mantle depth to the seafloor in the Mariana forearc region by serpentinite mud volcanoes,providing exceptional opportunities to directly study the subducted oceanic crust and *** International Ocean Discovery Program(IODP)expedition 366 has recovered a few metamorphosed mafic clasts exhumed from the Mariana forearc serpentinite mud volcanoes,e.g.,the Fantangis?a and Asùt Tesoru *** mafic clasts have tholeiitic to alkaline affinities with distinct trace elements and Nd-Hf isotopes characteristics,suggesting different provenances and mantle *** tholeiites from the Fantangisna Seamount have trace element characteristics typical of mid-ocean ridge *** Pacific-type Hf-Nd isotopic compositions,combined with the greenschist metamorphism of these tholeiites further suggest that they came from the subducted Pacific oceanic *** alkali basalts-dolerites from the Fantangisna and Asùt Tesoru seamounts show ocean island basalt(OIB)-like geochemical *** OIB-like geochemical signatures and the low-grade metamorphism of these alkali basalts-dolerites suggest they came from subducted seamounts that originally formed in an intraplate setting on the Pacific *** Pacific Plate origin of these metabasites suggests they were formed in the Early Cretaceous or *** types of OIBs have been recognized from alkali metabasites,one of which is geochemically similar to the HIMU-EMI-type OIBs from the West Pacific Seamount Province,and another is similar to the EM

关键词： IODP 366 Mariana convergent margin Forearc Seamount subduction OIB