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Geochronology and Geochemistry of Paleozoic S-type Granites in the Western Segment of the East Kunlun Orogen and its Implications for Tectonic Evolution
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作者 REN Haidong PAN Tong +5 位作者 WANG Tao WANG Bingzhang WANG Xiaoxia ZHANG Jianjun WANG Jianguo ZHAO Wentao 《Acta Geologica Sinica(English Edition)》 2025年第3期743-760,共18页
In the western segment of the East Kunlun Orogen(WEKO),muscovite granite and garnet granite from the Hureguole intrusion exhibit zircon U-Pb ages of 435-442 Ma.Geochemically,these rocks contain high concentrations of ... In the western segment of the East Kunlun Orogen(WEKO),muscovite granite and garnet granite from the Hureguole intrusion exhibit zircon U-Pb ages of 435-442 Ma.Geochemically,these rocks contain high concentrations of SiO_(2),K_(2)O and Al_(2)O_(3),with low concentrations of TiO_(2)and MgO,indicating a peraluminous high-K calc-alkaline affinity.They are enriched in Rb,Th,U and LREE,depleted in Eu,Ba,Sr and Ti,being classified as S-type granites.Negative whole-rockε_(Nd)(t)values(-9.8 to-9.1)and zirconε_(Hf)(t)values(-11.6 to-8.2)for those granites indicate that they were derived from partial melting of pelitic rocks in the Paleoproterozoic Baishahe Formation of the Jinshuikou Group.Based on the collected zircon ages,Cambrian-Devonian magmatic activity in the WEKO was divided into three stages:early(446-520 Ma),middle(427-441 Ma)and late(372-424 Ma)stages.Statistically,whole-rock Nd and zircon Hf isotope data(ε_(Nd)(t)/T_(DM)^(Nd),ε_(Hf)(t)/T_(DMC)^(Hf))from Paleozoic igneous rocks in the WEKO reveal a magma source that was initially dominated by depleted mantle components in the northward subduction stage of the Proto-Tethy an Ocean plate(446-520 Ma),shifting to predominantly crustal sources during the closure period of the North Qimantagh back-arc basin(427-441 Ma),then to crust-mantle mixed sources in the post-collision stage(372-424 Ma). 展开更多
关键词 Nd-Hf isotopes s-type granite magmatic activity SILURIAN East Kunlun Orogen
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Petrogenesis,Tectonics,and Metallogenic Potential of Early Paleozoic S-type Granites in Pinghe,Southwestern Yunnan,China
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作者 LI Guangjie CHEN Yongqing 《Acta Geologica Sinica(English Edition)》 2025年第5期1314-1327,共14页
A systematic study of early Paleozoic S-type granites in Pinghe enhances our understanding of the tectonic evolution of proto-Tethys and provides a foundation for exploring rare metal deposits in the region.The Pinghe... A systematic study of early Paleozoic S-type granites in Pinghe enhances our understanding of the tectonic evolution of proto-Tethys and provides a foundation for exploring rare metal deposits in the region.The Pinghe granites consist of monzogranite and leucogranite.Zircon U-Pb dating shows that the emplacement ages of the monzogranite and leucogranite are 502.0 Ma and 500.9 Ma,respectively.All samples have high SiO_(2) content and a weakly to strongly peraluminous character(A/CNK=1.08-1.23),consistent with S-type granites.The monzogranite has relatively high CaO,Sr,Ba,and CaO/Na_(2)O ratios but lower Rb.In contrast,the leucogranite has lower CaO,Sr,Ba,and CaO/Na_(2)O ratios but higher Rb.The similar ε_(Nd)(t)values(−9.3 to−8.4)and Pb isotopic compositions((^(206)Pb/^(204)Pb)t=18.03-19.36,(^(207)Pb/^(204)Pb)t=15.66-15.76,(^(208)Pb/^(204)Pb)t=37.97-38.55)suggest that the monzogranite formed through partial melting of crustal greywacke,while the leucogranite originated from partial melting of crustal pelite.Regional geological studies suggest that these S-type granites in Pinghe were emplaced in an active continental margin setting,associated with the westward subduction of the proto-Tethys oceanic slab.The geochemical characteristics of leucogranite are consistent with those of tungsten-tin-related granites,indicating significant metallogenic potential for W and Sn deposits. 展开更多
关键词 early Paleozoic granites s-type granites tectonics and metallogenic potential proto-Tethys Southwestern Yunnan
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Genetic diversity of the S-type small subunit ribosomal RNA gene of Plasmodium knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia
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作者 Eric Tzyy Jiann Chong Joveen Wan Fen Neoh +3 位作者 Tiek Ying Lau Kek Heng Chua Yvonne Ai-Lian Lim Ping-Chin Lee 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2024年第2期84-90,共7页
Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and hap... Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and haplotype.Methods:Thirty-nine blood samples infected with P.knowlesi were collected in Sabah,Malaysian Borneo and Peninsular Malaysia.The S-type SSU rRNA gene was amplified using polymerase chain reaction,cloned into a vector,and sequenced.The natural selection and haplotype of the S-type SSU rRNA gene sequences were determined using DnaSP v6 and illustrated using NETWORK v10.This study's 39 S-type SSU rRNA sequences and eight sequences from the Genbank database were subjected to phylogenetic analysis using MEGA 11.Results:Overall,the phylogenetic analysis showed no evidence of a geographical cluster of P.knowlesi isolates from different areas in Malaysia based on the S-type SSU rRNA gene sequences.The S-type SSU rRNA gene sequences were relatively conserved and with a purifying effect.Haplotype sharing of the S-type SSU rRNA gene was observed between the P.knowlesi isolates in Sabah,Malaysian Borneo,but not between Sabah,Malaysian Borneo and Peninsular Malaysia.Conclusions:This study suggests that the S-type SSU rRNA gene of P.knowlesi isolates in Sabah,Malaysian Borneo,and Peninsular Malaysia has fewer polymorphic sites,representing the conservation of the gene.These features make the S-type SSU rRNA gene suitable for comparative studies,such as determining the evolutionary relationships and common ancestry among P.knowlesi species. 展开更多
关键词 Plasmodium knowlesi s-type small subunit ribosomal RNA Genetic diversity Natural selection HAPLOTYPE
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英国制造——捷豹XJ8和S-TYPE中国上市
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作者 孙磊 晓军 《汽车与驾驶维修》 2004年第7期12-14,共3页
虽然在世界汽车制造中,无论是汽车品牌的数量还是汽车的产销量,英国都难以与美国、日本、德国以及法国等相比。但是有一点不可否认,那就是英国在豪华车领域具有无与伦比的地位,像劳斯莱斯、宾利、罗孚、捷豹、阿斯顿·马丁以及... 虽然在世界汽车制造中,无论是汽车品牌的数量还是汽车的产销量,英国都难以与美国、日本、德国以及法国等相比。但是有一点不可否认,那就是英国在豪华车领域具有无与伦比的地位,像劳斯莱斯、宾利、罗孚、捷豹、阿斯顿·马丁以及莲花等。 展开更多
关键词 英国 捷豹XJ8 s-type 中国 汽车市场 市场推广 轿车 车型
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Speed Planning Algorithm Based on Improved S-Type Acceleration and Deceleration Model 被引量:7
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作者 LUO Huimiao ZHAO Dongbiao FU Wenqiang 《Journal of Shanghai Jiaotong university(Science)》 EI 2021年第6期786-793,共8页
The acceleration saltation of the traditional S-type acceleration model in the speed planning of the NURBS curve will result in the vibration and flexible impact of the machine tool.It will affect the surface quality ... The acceleration saltation of the traditional S-type acceleration model in the speed planning of the NURBS curve will result in the vibration and flexible impact of the machine tool.It will affect the surface quality of the components.The high speed smooth S-type acceleration and deceleration model deals with flexible impact,but the calculation is tedious.Aimed at the above problems,the traditional S-type acceleration and deceleration model is improved to make the jerk change linearly at a certain slope to reduce the flexible impact.Before the speed planning,it is needed to find the arc length and curvature of each point on the NURBS curve with a tiny step,and to determine the speed sensitivity point on the curve accordingly.According to the speed sensitive point,the NURBS curve is segmented.The attribute parameters of each section are determined by adaptive speed planning.Then,the speed planning can be performed on the NURBS curve according to the speed characteristics classification.The simulation results show that the algorithm can effectively reduce the flexible impact,improve the machining precision and efficiency,and simplify the classification of speed characteristics. 展开更多
关键词 speed planning flexible impact classification of speed characteristics improved s-type acceleration and deceleration
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Genesis of S-type Granites in the Pengshan Sn-polymetallic Ore Field, Northern Jiangxi Province and its Implications 被引量:2
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作者 YIN Qingqing XIANG Xinkui +6 位作者 YU Zhendong YANG Xiufeng WANG Tianchen ZHONG Bo TAN Rong LIAO Jianhai ZHU Yuansong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2020年第6期1860-1873,共14页
The Pengshan Sn-polymetallic ore field is located in the southeastern part of the Yangtze block,spanning the southeast edge of the MLYDZ and the northern edge of the mid-segment of the Jiangnan Uplift,and on one side ... The Pengshan Sn-polymetallic ore field is located in the southeastern part of the Yangtze block,spanning the southeast edge of the MLYDZ and the northern edge of the mid-segment of the Jiangnan Uplift,and on one side of the MLYDZ.The studies of LA-ICP-MS zircon U-Pb chronology and petrogeochemistry for Early Cretaceous acid granites from the Pengshan ore field were carried out in this paper.We report zircon U-Pb geochronology and whole-rock geochemistry for acid granites in the Pengshan ore field.The zircon U-Pb ages of the muscovite-granite,biotite adamellite and granite-porphyry are 127.6±1.7 Ma,126.9±1.6 Ma and 126.6±2.0 Ma,respectively.The granites in Pengshan are characterized by a high silicon content and are rich in alkali.They belong to high-potassium,calc-alkaline,peraluminous granite.The rocks have a relatively high Rb/Ba ratio,and the data points for muscovite-granite and biotite adamellite all fall within the clay-rich sources region,near the pelite-derived end-member,showing that the Pengshan muscovite-granite and biotite adamellite mainly originated from the partial melting of metapelites with high maturity.The transformation of the compressional and extensional tectonics in this region approximately 128 Ma obviously lags behind that in the mid-segment of the Jiangnan Uplift(135 Ma),but occurred earlier than the MLYDZ(126 Ma).The Pengshan ore field extends from the mid-segment of the Jiangnan Uplift to the MLYDZ.Although the tectonic stress field is constrained by the combination of the two secondary tectonic units,the time of tectonic system transformation is closer to the MLYDZ because the spatial orientation of the area is enclosed in the MLYDZ.Relevant geophysical and drilling data confirm the rationality of Pengshan-Ao'xia as a multi-center vertical zoning ore field,and show the scientificity of the prospecting idea of abutting joint between the north-west of Pengshan area and the south-east of Ao'xia area. 展开更多
关键词 zircon dating s-type granite Early Cretaceous syn-collisional DYNAMICS Pengshan Sn-polymetallic ore field
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Fiber cladding dual channel surface plasmon resonance sensor based on S-type fiber 被引量:1
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作者 魏勇 赵晓玲 +6 位作者 刘春兰 王锐 蒋天赐 李玲玲 石晨 刘纯彪 竺栋 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期187-195,共9页
Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an ... Fiber cladding surface plasmon resonance(SPR)sensors have few structures,and a clad SPR sensor based on S-type fiber is proposed in this paper.This new type of fiber cladding SPR sensor was formed by electrofusing an S-shaped structure on the fiber to couple the light in the fiber core to the cladding.In this paper,the effects of fiber parameters on the performance of the sensor were studied by simulation and experiment.Based on the conclusion that the smaller the core diameter is,the closer the working band of the SPR resonance is to long wavelengths,and that the geometric characteristics mean that a multimode fiber can receive the fiber cladding light from a small core diameter few-mode fiber,a dual channel SPR sensor with a double S-type fiber cascade was proposed.In the refractive index detection range of 1.333–1.385refractive index units(RIU),the resonant working band of channel I is 627.66 nm–759.78 nm,with an average sensitivity of 2540.77 nm/RIU,and the resonant working band of channel II is 518.24 nm–658.2 nm,with an average sensitivity of2691.54 nm/RIU.The processing method for the S-type fiber cladding SPR sensor is simple,effectively solving the problem of this type of SPR sensor structure and the difficult realization of a dual channel.The sensor is expected to be used in the fields of medical treatment and biological analysis. 展开更多
关键词 surface plasmon resonance(SPR) s-type structure dual channel cladding fiber SPR sensor
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Bandgap Properties for the Folded S-Type Periodic Structure:Numerical Simulation and Experiment 被引量:1
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作者 Tongtong Huo Zhijing Wu Fengming Li 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2023年第5期624-632,共9页
The central wavelength of the first Bragg scattering bandgap is approximately twice that of the lattice.Therefore,a low-frequency Bragg scattering bandgap with a small structural dimension for phononic crystals is dif... The central wavelength of the first Bragg scattering bandgap is approximately twice that of the lattice.Therefore,a low-frequency Bragg scattering bandgap with a small structural dimension for phononic crystals is difficult to obtain.In this study,a folded S-type periodic structure is developed to reduce the dimension in the direction of vibration suppression by folding unit cells.According to the foregoing,an improved folded S-type periodic structure with different unit cell arrangements is designed to widen the bandgap frequency range.Energy band diagrams and frequency responses are calculated based on the Bloch theory and using the finite element method.Furthermore,a prototype of the improved folded S-type periodic structure is fabricated using a three-dimensional printing technique,and a vibration experiment is conducted.To verify the vibration reduction performance of the structure,numerical simulation and experimental results are compared.This type of folded periodic structure can effectively reduce dimensions to satisfy the dimension requirements pertaining to the direction of vibration suppression.Hence,the foregoing can aid in promoting the use of elastic bandgap structures in engineering. 展开更多
关键词 Folded s-type periodic structure Bandgap Vibration reduction Finite element method Vibration experiment
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Chronology and Genesis of S-type Granites in Hetai District, Guangdong Province: Constraints from LA-ICP-MS Zircon U-Pb Dating and Tourmaline Boron Isotope In-situ Analyses 被引量:1
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作者 WANG Lixing XU Deru +1 位作者 CHEN Genwen ZHU Yuhua 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期96-97,共2页
1 Introduction Hetai district,which is a mountainous area,situated on Guangning and Zhaoqing city,west Guangdong Province.Hetai district is generally located on southwest of South China Caledonian fold belt,east margi... 1 Introduction Hetai district,which is a mountainous area,situated on Guangning and Zhaoqing city,west Guangdong Province.Hetai district is generally located on southwest of South China Caledonian fold belt,east margin of Yunkai post-Caledonian uplift.Multiple type granites are widely distributed in Hetai district,including Caledonian,Indosinian and Yanshanian granites.Based on different 展开更多
关键词 Pb Chronology and Genesis of s-type Granites in Hetai District Constraints from LA-ICP-MS Zircon U-Pb Dating and Tourmaline Boron Isotope In-situ Analyses Guangdong Province type
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Weighted composition operators from F(p,q,s) spaces to Bers-type spaces in the unit ball 被引量:2
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作者 LU Xiao-fen 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2009年第4期462-472,共11页
This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to ... This paper deals with the boundedness and compactness of the weighted composition operators from the F(p, q, s) spaces, including Hardy space, Bergman space, Qp space, BMOA space, Besov space and α-Bloch space, to Bers-type spaces Hv^∞( or little Bers-type spaces Hv,o∞ ), where v is normal. 展开更多
关键词 F(p Q s) space Bers-type space weighted composition operator unit ball
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Activation of Sonic Hedgehog Signaling Pathway in S-type Neuroblastoma Cell Lines
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作者 周昱男 戴若连 +4 位作者 毛玲 夏远鹏 姚玉芳 杨雪 胡波 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2010年第3期271-277,共7页
The effects of Sonic hedgehog(Shh) signaling pathway activation on S-type neuroblastoma(NB) cell lines and its role in NB tumorigenesis were investigated.Immunohistochemistry was used to detect the expression of Shh p... The effects of Sonic hedgehog(Shh) signaling pathway activation on S-type neuroblastoma(NB) cell lines and its role in NB tumorigenesis were investigated.Immunohistochemistry was used to detect the expression of Shh pathway components— Patched1(PTCH1) and Gli1 in 40 human primary NB samples.Western blotting and RT-PCR were used to examine the protein expression and mRNA levels of PTCH1 and Gli1 in three kinds of S-type NB cell lines(SK-N-AS,SK-N-SH and SHEP1),respectively.Exogenous Shh was administrated to activate Shh signaling pathway while cyclopamine was used as a selective antagonist of Shh pathway.S-type NB cell lines were treated with different concentrations of Shh or/and cyclopamine for different durations.Cell viability was measured by using MTT method.Apoptosis rate and cell cycle were assayed by flow cytometry.The xenograft experiments were used to evaluate the role of Shh pathway in tumor growth in immunodeficient mice.High-level expression of PTCH1 and Gli1 was detected in both NB samples and S-type NB cell lines.Cyclopamine decreased the survival rate of the three cell lines while Shh increased it,and the inhibition effects of cyclopamine could be partially reversed by shh pre-treatment.Cyclopamine induced the cell apoptosis and the cell cycle arrest in G0/G1 phase,while Shh induced the reverse effects and could partially prevent effects of cyclopamine.Cyclopamine could also inhibit the growth of NB in vivo.Our studies revealed that activation of the Shh pathway is important for survival and proliferation of S-type NB cells in vivo and in vitro through affecting cell apoptosis and cell cycle,suggesting a new therapeutic approach to NB. 展开更多
关键词 s-type neuroblastoma cell lines Sonic hedgehog signaling pathway CYCLOPAMINE
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挑战“双B”美洲豹新鲜出击——Jaguar New S-Type 3.0
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作者 孙祥隆 《轻型汽车技术》 2004年第6期77-80,共4页
在迈入21世纪之始,Jaguar以S-Type作为首次跨入主管级豪华房车市场区区的开路先锋,当时汇集最尖端工艺技术、融合独特设计创意的S-Type,一推出便深受全球车坛的瞩目,同时也为TAGUAR揭开世纪交替的序幕,为日后上市的X-Type.全新XJ... 在迈入21世纪之始,Jaguar以S-Type作为首次跨入主管级豪华房车市场区区的开路先锋,当时汇集最尖端工艺技术、融合独特设计创意的S-Type,一推出便深受全球车坛的瞩目,同时也为TAGUAR揭开世纪交替的序幕,为日后上市的X-Type.全新XJ系列奠下良好的基础。转眼间。 展开更多
关键词 JAGUAR NEW s-type轿车 车型设计 动力性能 操控性能
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捷豹S-Type
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作者 佟星 《汽车驾驶员》 2007年第8期38-39,共2页
你可以花60万元买到一款豪华轿车,但你未必就能因此收获到更多的魅力。一只充满灵性的飞豹划过长空,惊艳之中彰显绅士气质,这样的魅力,谁人可挡呢?
关键词 捷豹s-type 汽车 内饰 外观 技术参数
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2005款捷豹S-TYPE电子手刹故障
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作者 罗凯 《汽车维修技师》 2013年第1期87-88,共2页
车型:2005款捷豹S-TYPE. 行驶里程:137750km. 故障现象:仪表上制动系统报警灯点亮,有时电子手刹无法释放. 故障诊断:接车后,验证故障现象,确如客户所述.使用SDD诊断仪进入系统读取故障码,发现在相关事件里面并没有相关的故障码. 执行建... 车型:2005款捷豹S-TYPE. 行驶里程:137750km. 故障现象:仪表上制动系统报警灯点亮,有时电子手刹无法释放. 故障诊断:接车后,验证故障现象,确如客户所述.使用SDD诊断仪进入系统读取故障码,发现在相关事件里面并没有相关的故障码. 执行建议选项,建议诊断驻车执行机构.点击确定以后,听到电机转动的声音,车辆手刹也可以正常的运作.以为只是一起偶发故障,在经过几次测试后均没问题,将车交与客户使用. 展开更多
关键词 手刹 手制动器 s-type 捷豹 电子 轻子
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绅士变身记 JAGUAR S-TYPE & JAGUAR XF
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作者 张研 王一鸣 霍庆泽 《世界汽车》 2016年第5期58-69,共12页
"犹记得戴安娜王妃初入皇室时,她驾驶着一辆经典的绿色S-Type,这款贵族座驾身形圆润、极富美感,不仅与王妃高贵气质相得益彰,也诠释着捷豹早期所崇尚的复古主义经典造型。跨入21世纪,捷豹全球设计总监严凯伦先生以一款风尚魅力的X... "犹记得戴安娜王妃初入皇室时,她驾驶着一辆经典的绿色S-Type,这款贵族座驾身形圆润、极富美感,不仅与王妃高贵气质相得益彰,也诠释着捷豹早期所崇尚的复古主义经典造型。跨入21世纪,捷豹全球设计总监严凯伦先生以一款风尚魅力的XF向世界昭告捷豹全新时代的到来,为我们演绎了一出精妙绝伦的绅士变身记。" 展开更多
关键词 捷豹 复古主义 高贵气质 设计总监 座驾 凯伦 JAGUAR s-type JAGUAR XF 转向盘 戴安娜
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2003款美洲虎S-Type R轿车
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《世界汽车》 2002年第12期33-34,共2页
在推出美洲虎S-Type轿车3年之后,美洲虎发布了全新设计的2003款S-Type R轿车。新款美洲虎S-Type R轿车在外型上没有做太大的改动,但为了显示其卓越的性能,对其内在结构进行了较大的改进。除了与车身同色的网状散热器护罩外。
关键词 2003款美洲虎s-type R轿车 性能特点 设计 结构配置 技术装备
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移动的古朴——试驾捷豹S-Type 3.0
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作者 敬伟 《汽车时代》 2004年第11期34-37,共4页
一场热闹非凡的F1上海站赛事,让很多人领略了一级方程式赛车那V10发动机发出的刺耳狂嚣,记住了车神舒马赫那菲夷所思的冲出赛道、撞车、爆胎等意外,如此诸多的新闻及花絮中,一则捷豹车队将要退出F1赛事的新闻吸引了我的注意。
关键词 捷豹 s-type 3.0 一级方程式赛车 舒马赫 上海站 车神 驻车制动 前大灯 侧面碰撞 自动变
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A GENERALIZED GAUSS-TYPE QUADRATURE FORMULA AND ITS APPLICATIONS TO PSEUDOSPECTRAL METHOD
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作者 王立联 郭本瑜 王中庆 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2002年第2期179-196,共18页
A generalized Gauss-type quadrature formula is introduced, which assists in selection of collocation points in pseudospectral method for differential equations with two-point derivative boundary conditions. Some resul... A generalized Gauss-type quadrature formula is introduced, which assists in selection of collocation points in pseudospectral method for differential equations with two-point derivative boundary conditions. Some results on the related Jacobi interpolation are established. A pseudospectral scheme is proposed for the Kuramoto-Sivashisky equation. A skew symmetric decomposition is used for dealing with the nonlinear convection term. The stability and convergence of the proposed scheme are proved. The error estimates are obtained. Numerical results show the efficiency of this approach. 展开更多
关键词 GENERALIZED Gauss-type QUADRATURE formula PSEUDOSPECTRAL method K-S equa-tion.
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采用改进遗传算法的无线电能传输系统参数优化设计 被引量:3
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作者 杨阳 章治 +2 位作者 吴雪钰 曹嘉亿 郑晅 《西安交通大学学报》 北大核心 2025年第4期93-104,共12页
针对高阶补偿拓扑的无线电能传输(WPT)系统的谐振参数较多且相互关联,从而导致系统设计时各个元件具体参数难以确定的问题,提出了一种适用于一次侧LCC、二次侧LC串联拓扑(LCC-S)的WPT系统参数优化设计方法。利用MATLAB/Simulink搭建WPT... 针对高阶补偿拓扑的无线电能传输(WPT)系统的谐振参数较多且相互关联,从而导致系统设计时各个元件具体参数难以确定的问题,提出了一种适用于一次侧LCC、二次侧LC串联拓扑(LCC-S)的WPT系统参数优化设计方法。利用MATLAB/Simulink搭建WPT系统仿真平台并进行理论分析,评估了谐振参数、耦合系数和等效负载对该系统输出特性的影响,选择影响程度最复杂的变量作为决策变量,构建系统非线性优化模型;以提高WPT系统的传输效率为目标,在遗传算法基础上加入非线性优化策略,并设计新的突变函数,利用改进后的遗传算法(IGA)给出了系统参数的优化设计方案。仿真结果表明:IGA使系统传输效率达到98.34%,相较遗传算法提高了2.52%,且收敛速度显著提高。搭建WPT系统实验平台并进行测试,结果表明:该系统能够以97.98%的传输效率保持300 W的功率输出;当负载电阻处于6~46Ω时,系统传输效率能够维持在90%以上。研究结果可为LCC-S型WPT系统参数设计提供参考。 展开更多
关键词 无线电能传输 LCC-S型 拓扑结构 改进遗传算法 谐振参数优化
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孙氏手术治疗Stanford A型主动脉夹层患者术后发生3期急性肾损伤的危险因素分析 被引量:2
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作者 白耀邦 吴振华 +2 位作者 齐玉娟 焦妍 姜楠 《中国心血管杂志》 北大核心 2025年第1期63-68,共6页
目的探讨孙氏手术治疗的Stanford A型主动脉夹层(TAAD)患者术后发生3期急性肾损伤(AKI)的危险因素。方法单中心、回顾性研究。连续收集2020年1月至2022年6月于天津市胸科医院心外科行孙氏手术治疗的224例TAAD患者的临床资料,其中男性167... 目的探讨孙氏手术治疗的Stanford A型主动脉夹层(TAAD)患者术后发生3期急性肾损伤(AKI)的危险因素。方法单中心、回顾性研究。连续收集2020年1月至2022年6月于天津市胸科医院心外科行孙氏手术治疗的224例TAAD患者的临床资料,其中男性167例(74.6%)。以患者入院时血肌酐水平为基线值,根据改善全球肾脏病预后组织(KDIGO)共识的AKI诊断和分期标准,将患者术后分为3期AKI组和非3期AKI组。通过单因素和多因素logistic回归分析筛选出孙氏手术治疗的TAAD患者术后发生3期AKI的独立危险因素,并依据危险因素建立预测模型。采用受试者工作特征(ROC)曲线下面积(AUC)判断模型对孙氏手术治疗的TAAD患者术后发生3期AKI的预测价值。结果224例TAAD患者术后有34例发生3期AKI,发生率为15.2%。与非3期AKI组比较,3期AKI组患者的基线资料中夹层累及肾动脉比例、中性粒细胞/淋巴细胞比值、血肌酐水平较高和总蛋白水平较低,术中体外循环时间、主动脉阻断时间和手术时间较长、输血量较大、使用重组人凝血因子Ⅶ比例较高和术后血小板计数较低,差异均有统计学意义(均为P<0.05)。多因素logistic回归分析结果显示,夹层累及肾动脉(OR=2.734,95%CI:1.102~6.786,P=0.032)、术前血肌酐水平(OR=1.019,95%CI:1.008~1.030,P=0.001)、术中输血量(OR=1.114,95%CI:1.008~1.288,P=0.037)和术后血小板计数(OR=0.980,95%CI:0.964~0.996,P=0.017)是TAAD患者经孙氏手术治疗后发生3期AKI的独立影响因素。应用多因素分析结果建立预测模型,绘制ROC曲线,结果显示该模型对孙氏手术治疗的TAAD患者术后发生3期AKI的预测准确性为84.3%(AUC=0.843,95%CI:0.774~0.913)。结论夹层累及肾动脉、术前血肌酐水平高、术中输血量大和术后血小板计数低的TAAD患者行孙氏手术治疗后更容易发生3期AKI。 展开更多
关键词 孙氏手术 Stanford A型主动脉夹层 急性肾损伤 危险因素
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