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Application of Milankovitch cycles in the restoration of highresolution deposition velocity of Neogene strata in Kutei Basin,Indonesia
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作者 Baonian Wu Zhijun Jin 《Energy Geoscience》 2023年第2期91-99,共9页
Restoring the deposition velocity during evolution in basin analysis is an important aspect.The restoration of high-resolution deposition velocitydthe deposition velocity over a short geological perioddcan improve the... Restoring the deposition velocity during evolution in basin analysis is an important aspect.The restoration of high-resolution deposition velocitydthe deposition velocity over a short geological perioddcan improve the precision of basin analysis and research.However,the prerequisite for the restoration is to establish an accurate chronostratigraphic framework based on precise stratigraphic dating.Conventional methods for stratigraphic dating can only be used to determine the epochs of large stratigraphic intervals rather than accurate geological time.It is also difficult to establish a fine geological time scale with dating methods requiring sample testing such as isotopic dating due to their limitations in sample collection.In contrast,the Milankovich cycle-based dating possesses the advantages of high precision and high operability and can be used to restore high-resolution deposition velocity.Based on the identification and extraction of Milankovich cycles,this study restores the high-resolution deposition velocity of the Middle Miocene and later strata in the abyssal area of the Kutei Basin in Indonesia.The results show that the restored deposition velocity coincides well with lithological sections.This indicates that the Milankovitch cycle-based dating can be used to effectively restore reliable curves of high-resolution deposition velocity.Therefore,this study provides a methodological basis and data guarantee for studying the accumulation cycles and distribution patterns of oil and gas in the abyssal area of the Kutei Basin using wave analysis technology and can also serve as a reference for similar research in other basins. 展开更多
关键词 Stratigraphic dating deposition velocity restoration Milankovitch cycle Kutei basin
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Cycles of fine-grained sedimentation and their influences on organic matter distribution in the second member of Paleogene Kongdian Formation in Cangdong Sag,Bohai Bay Basin,East China
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作者 ZHAO Xianzheng PU Xiugang +10 位作者 YAN Jihua JIN Fengming SHI Zhannan CHAI Gongquan HAN Wenzhong LIU Yan JIANG Wenya CHEN Changwei ZHANG Wei FANG Zheng XIE Delu 《Petroleum Exploration and Development》 SCIE 2023年第3期534-546,共13页
According to the theory of sequence stratigraphy based on continental transgressive-regressive(T-R)cycles,a 500 m continuous core taken from the second member of Kongdian Formation(Kong 2 Member)of Paleogene in Well G... According to the theory of sequence stratigraphy based on continental transgressive-regressive(T-R)cycles,a 500 m continuous core taken from the second member of Kongdian Formation(Kong 2 Member)of Paleogene in Well G108-8 in the Cangdong Sag,Bohai Bay Basin,was tested and analyzed to clarify the high-frequency cycles of deep-water fine-grained sedimentary rocks in lacustrine basins.A logging vectorgraph in red pattern was plotted,and then a sequence stratigraphic framework with five-order high-frequency cycles was formed for the fine-grained sedimentary rocks in the Kong 2 Member.The high-frequency cycles of fine-grained sedimentary rocks were characterized by using different methods and at different scales.It is found that the fifth-order T cycles record a high content of terrigenous clastic minerals,a low paleosalinity,a relatively humid paleoclimate and a high density of laminae,while the fifth-order R cycles display a high content of carbonate minerals,a high paleosalinity,a dry paleoclimate and a low density of laminae.The changes in high-frequency cycles controlled the abundance and type of organic matter.The T cycles exhibit relatively high TOC and abundant endogenous organic matters in water in addition to terrigenous organic matters,implying a high primary productivity of lake for the generation and enrichment of shale oil. 展开更多
关键词 fine-grained sediment high-frequency cycle lamina density organic matter Paleogene Kong 2 Member Cangdong Sag Bohai Bay Basin
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High-Frequency AlGaN/GaN High-Electron-Mobility Transistors with Regrown Ohmic Contacts by Metal-Organic Chemical Vapor Deposition 被引量:5
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作者 郭红雨 吕元杰 +7 位作者 顾国栋 敦少博 房玉龙 张志荣 谭鑫 宋旭波 周幸叶 冯志红 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第11期166-168,共3页
Nonalloyed ohmic contacts regrown by metal-organic chemical vapor deposition are performed on AlGaN/GaN high-electron-mobility transistors. Low ohmic contact resistance of 0.15Ω.mm is obtained. It is found that the s... Nonalloyed ohmic contacts regrown by metal-organic chemical vapor deposition are performed on AlGaN/GaN high-electron-mobility transistors. Low ohmic contact resistance of 0.15Ω.mm is obtained. It is found that the sidewall obliquity near the regrown interface induced by the plasma dry etching has great influence on the total contact resistance. The fabricated device with a 100-nm T-shaped gate demonstrates a maximum drain current density of 0.95 A/mm at Vgs = 1 V and a maximum peak extrinsic transcondutance Gm of 216mS/ram. Moreover, a current gain cut-off frequency fT of 115 GHz and a maximum oscillation frequency fmax of 127 GHz are achieved. 展开更多
关键词 GAN high-frequency AlGaN/GaN High-Electron-Mobility Transistors with Regrown Ohmic Contacts by Metal-Organic Chemical Vapor deposition
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Tailoring microstructure evolution and mechanical properties of a high-performance alloy steel through controlled thermal cycles of a direct laser depositing process
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作者 Shi-yun Dong Xuan Zhao +5 位作者 Shi-xing Yan Yao-hui Lü Xiao-ting Liu Yu-xin Liu Peng He Bin-shi Xu 《China Foundry》 SCIE CAS 2021年第5期463-473,共11页
Direct laser deposition(DLD),as a popular metal additive manufacturing process,shows advantages of technical flexibility and high efficiency to gain a high-performance alloy steel component.However,during the processi... Direct laser deposition(DLD),as a popular metal additive manufacturing process,shows advantages of technical flexibility and high efficiency to gain a high-performance alloy steel component.However,during the processing of DLD,the deposited steel layer is affected by the subsequent layer depositing.The DLD block shows different microstructure and mechanical properties at the bottom,middle and top of the deposited parts.To date,there are few research works about the effects of inter-layer interval time and laser power on the microstructure evolution and mechanical properties of the deposited layers.In this study,the idle time and laser power layer by layer during DLD of 12CrNi2 steel were controlled to cause the deposited layers to maintain a high cooling rate,while the bottom deposited layer was subjected to a weak tempering effect.Results show that a high proportion of martensite is produced,which improves the strength of the deposited layer.Under the laser scanning strategy of laser power 2,500 W,scanning velocity 5 mm·s^(-1),powder feeding rate 11 g·min^(-1),overlap rate 50%,and a laser power difference of 50 W and a 2 min interval,the tensile strength of the deposited layer of 12CrNi2 steel is in the range of 873-1,022 MPa,and the elongation is in the range of 16.2%-18.9%.This study provides a method to reduce the tempering effect of the subsequent deposition layers on the bottom layers,which can increase the proportion of martensite in the low-alloy high-strength steel,so as to improve the yield strength of the alloy steel. 展开更多
关键词 alloy steel direct laser deposition thermal cycles microstructure evolution mechanical properties
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Low cycle fatigue behavior of laser melting deposited TC18 titanium alloy 被引量:7
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作者 李真 田象军 +1 位作者 汤海波 王华明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第9期2591-2597,共7页
Low cycle fatigue (LCF) behavior of laser melting deposited (LMD) TC18 titanium alloy was studied at room temperature. Microstructure consisting of fine lamella-like primary α phase and transformed β matrix was ... Low cycle fatigue (LCF) behavior of laser melting deposited (LMD) TC18 titanium alloy was studied at room temperature. Microstructure consisting of fine lamella-like primary α phase and transformed β matrix was obtained by double annealed treatment, and inhomogeneous grain boundaryαphase was detected. Fatigue fracture surfaces and longitudinal sections of LCF specimens were examined by optical microscopy and scanning electron microscopy. Results indicate that more than one crack initiation site can be detected on the LCF fracture surface. The fracture morphology of the secondary crack initiation site is different from that of the primary crack initiation site. When the crack grows along the grain boundaryαphase, continuous grain boundaryαphase leads to a straight propagating manner while discontinuous grain boundaryαphase gives rise to flexural propagating mode. 展开更多
关键词 titanium alloy low cycle fatigue laser melting deposition
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Effect of Multiple Thermal Cycles on Microstructure and Mechanical Properties of Cu Modified Ti64 Thin Wall Fabricated by Wire-Arc Directed Energy Deposition
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作者 Zidong Lin Xuefeng Zhao +5 位作者 Wei Ya Yan Li Zhen Sun Shiwei Han Xiaoyang Peng Xinghua Yu 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2024年第11期1875-1890,共16页
This study investigated the effect of thermal cycles on Cu-modified Ti64 thin-walled components deposited using the wire-arc directed energy deposition(wire-arc DED)process.For the samples before and after experiencin... This study investigated the effect of thermal cycles on Cu-modified Ti64 thin-walled components deposited using the wire-arc directed energy deposition(wire-arc DED)process.For the samples before and after experiencing thermal cycles,it was found that both microstructures consisted of priorβ,grain boundaryα(GBα),and basketweave structures containingα+βlamellae.Thermal cycles realized the refinement ofαlaths,the coarsening of priorβgrains andβlaths,while the size and morphology of continuously distributed GBαremained unchanged.The residualβcontent was increased after thermal cycles.Compared with the heat-treated sample with nanoscale Ti2Cu formed,short residence time in high temperature caused by the rapid cooling rate of thermal cycles restricted Ti2Cu formation.No formation of brittle Ti2Cu means that only grain refinement strengthening and solid-solution strengthening matter.The yield strength increased from 809.9 to 910.85 MPa(12.46%increase).Among them,the main contribution from solid solution strengthening(~51 MPa)was due to the elemental redistribution effect betweenαandβphases caused by thermal cycles through quantitative analysis.The ultimate tensile strength increased from 918.5 to 974.22 MPa(6.1%increase),while fracture elongation increased from 6.78 to 10.66%(57.23%increase).Grain refinement ofαlaths,the promotedα′martensite decomposition,decreased aspect ratio,decreased Schmid factor,and local misorientation change ofαlaths are the main factors in improved ductility.Additionally,although the fracture modes of the samples in the top and middle regions are both brittle-ductile mixed fracture mode,the thermal cycles still contributed to an improvement in tensile ductility. 展开更多
关键词 Wire-arc directed energy deposition(wire-arc DED) Ti64-1.2Cu thin wall Thermal cycles Microstructure variation Mechanical properties
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Sedimentary system characteristics and depositional filling model of Upper Permian——Lower Triassic in South Yellow Sea Basin 被引量:6
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作者 YUAN Yong CHEN Jian-wen +3 位作者 ZHANG Yin-g ZHANG Yu-xi LIANG Jie ZHANG Peng-hui 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第12期2910-2928,共19页
In the South Yellow Sea Basin,Mesozoic–Paleozoic marine strata are generally well developed with large thickness,and no substantial breakthroughs have been made in hydrocarbon exploration.Through research,it is belie... In the South Yellow Sea Basin,Mesozoic–Paleozoic marine strata are generally well developed with large thickness,and no substantial breakthroughs have been made in hydrocarbon exploration.Through research,it is believed that the Upper Permian–Lower Triassic can be regarded as a long-term base-level cycle.Based on drilling data,characteristics of the lithology–electric property combination cyclicity,and the special lithology,the long-term base-level cycle was divided into five medium-term base-level cycles(MC1–MC5).On this basis,the Permian–Triassic sedimentary systems and their filling model were analyzed in accordance with the change of base-level cycle and transition of sedimentary environment,as well as characteristics of the drilling sedimentary facies and seismic facies.The results show that there were six sedimentary systems(fluvial,delta,tidal flat,open platform,restricted platform,and continental shelf)developed in the Upper Permian–Lower Triassic,the sedimentary systems were distributed such that the water was deep in the northwest and shallow in the southeast,and there were two base-level cycle filling models(a relatively stable tidal flat facies and a rapidly transgressive continental shelf facies to stable platform facies)developed in the Upper Permian–Lower Triassic.These models can provide a basis for evaluation of the Mesozoic–Paleozoic hydrocarbon geology in the South Yellow Sea Basin. 展开更多
关键词 sequence base-level cycle sedimentary system depositional filling model Upper Permian–Lower Triassic South Yellow Sea Basin
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LOW CYCLE FATIGUE IN TITANIUM ALUMINIUM FORMED BY CENTRIFUGAL SPRAY DEPOSITION 被引量:1
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作者 Chen Wenzhe, Zhang Sa and Qian KuangwuDepartment of Materials, Fuzhou University, Fuzhou 350002, P. R. ChinaGu HaichengSchool of Materials Science and Engineering, Xi′an Jiaotong University, Xi′an 710049, P. R. ChinaWang ZhongguangState K 《中国有色金属学会会刊:英文版》 CSCD 1998年第2期65-69,共5页
LOWCYCLEFATIGUEINTITANIUMALUMINIUMFORMEDBYCENTRIFUGALSPRAYDEPOSITION①ChenWenzhe,ZhangSaandQianKuangwuDepartm... LOWCYCLEFATIGUEINTITANIUMALUMINIUMFORMEDBYCENTRIFUGALSPRAYDEPOSITION①ChenWenzhe,ZhangSaandQianKuangwuDepartmentofMaterials,Fu... 展开更多
关键词 CENTRIFUGAL SPRAY depositION (CSD) Ti48Al2Mn2Nb low cyclE fatigue
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Breeding and Simple-rapid Regeneration Protocol for Jisheng 1 with Glandless Trait and High-frequency Somatic Embryo Production Ability 被引量:1
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作者 LI Wei-ming1,ZHANG Han-shuang1,ZHAO Jun-li1,SUN Jing-yan2(1.Cotton Research Institute of Haafs,Shijiazhuang,Hebei Province 050051,China 2.Hebei Normal University Shijiazhuang,Hebei Province 071001,China) 《棉花学报》 CSCD 北大核心 2008年第S1期95-,共1页
Most of model cotton varieties used in tissue culture have glands on both the reproductive and vegetative parts of the plant.These glands contain compounds that are toxic to human and non-ruminant animals.The presence... Most of model cotton varieties used in tissue culture have glands on both the reproductive and vegetative parts of the plant.These glands contain compounds that are toxic to human and non-ruminant animals.The presence of these compounds limits their usage as food and feed.To obtain a glandless cotton variety with high-frequency somatic embryo production ability,27 glandless varieties 展开更多
关键词 Breeding and Simple-rapid Regeneration Protocol for Jisheng 1 with Glandless Trait and high-frequency Somatic Embryo Production Ability MSB cycle
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Sea-level Eustatic Cycles and Potash Formation Event:A Case Study of Triassic Sichuan Basin
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作者 ZHOU Jiayun GONG Daxing +2 位作者 CHEN Kegui LI Chunmei LI Meng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期285-286,共2页
Identification of the favorable salt-and potash-forming layer,we still mainly rely on logging interpretation and coring verification.However,we both know that the continuously carbonate platform is cyclical growing.It... Identification of the favorable salt-and potash-forming layer,we still mainly rely on logging interpretation and coring verification.However,we both know that the continuously carbonate platform is cyclical growing.It has recorded valuable information about the phase transition of carbonate rocks,which were synchronized with the relative sea-level cycles.This paper presents a fast and 展开更多
关键词 Marine carbonate platform depositional cycles potassium-rich layer well logging response TRIASSIC Sichuan Basin
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中国锂矿的多旋回深循环内外生一体化成矿理论及其找矿应用 被引量:1
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作者 王登红 代鸿章 +9 位作者 刘善宝 王成辉 李建康 李鹏 陈郑辉 于扬 秦锦华 孙艳 娄德波 姚佛军 《地质学报》 EI CAS CSCD 北大核心 2024年第3期889-897,共9页
中国锂资源的分布具有卤水型与硬岩型相伴相随、若即若离的特点。“多旋回深循环内外生一体化”成锂理论,在多年三稀金属矿产找矿实践和理论研究的基础上不断丰富完善。中国锂矿的形成与“多旋回”构造运动密切相关,从前寒武纪到新生代... 中国锂资源的分布具有卤水型与硬岩型相伴相随、若即若离的特点。“多旋回深循环内外生一体化”成锂理论,在多年三稀金属矿产找矿实践和理论研究的基础上不断丰富完善。中国锂矿的形成与“多旋回”构造运动密切相关,从前寒武纪到新生代均有成矿潜力,可构成一个完整的多旋回成矿谱系。锂的“深循环”,一是锂深度参与成岩成矿的物质循环;二是需要一个“圈闭”的构造背景将锂“捕获”以避免其过度分散,锂从开始加入到岩浆与最终定位的深度之差,是硬岩型锂矿成矿的关键之一,压差越大越有利于伟晶岩型锂矿的形成。大量锂矿实例显示锂的物质循环是“内外生一体化”的统一过程,高海拔地区(山上)的含锂地质体(花岗岩类甚至直接就是含锂矿床)经风化剥蚀之后,可能成为沉积型锂矿的物质来源之一;而富含锂的沉积岩经过埋藏、变质、深熔也可以形成含锂的岩浆岩、伟晶岩。我国西部塔里木盆地、四川盆地、扎布耶盆地及东部的江汉盆地、吉泰盆地、周田盆地等大小不一的盆地均含锂,而其周边造山带中也不同程度发育硬岩型锂矿,这就为区域找矿指明了方向。“多旋回深循环内外生一体化”成锂理论是三稀矿产成矿理论的重要组成部分,为我国锂矿找矿工作提供了指导和借鉴,在甲基卡、可尔因、阿尔金、幕阜山等锂矿矿集区的找矿实践中发挥了积极作用。 展开更多
关键词 锂矿 构造运动 “多旋回深循环内外生一体化”成矿理论 找矿应用
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激光沉积Ti65钛合金低周疲劳性能
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作者 李晓丹 孙浩军 +5 位作者 殷俊 刘艳梅 倪家强 周松 安金岚 回丽 《有色金属工程》 CAS 北大核心 2024年第5期10-18,共9页
对激光沉积制造的Ti65钛合金进行室温低周疲劳实验,对比研究了高、低功率试样的低周疲劳性能。结果表明,高、低功率试样均表现出循环软化的特征,随着应变幅的增加,试样的软化率在不断提高;相同应变幅下,高功率试样的软化率和疲劳寿命高... 对激光沉积制造的Ti65钛合金进行室温低周疲劳实验,对比研究了高、低功率试样的低周疲劳性能。结果表明,高、低功率试样均表现出循环软化的特征,随着应变幅的增加,试样的软化率在不断提高;相同应变幅下,高功率试样的软化率和疲劳寿命高于低功率试样。通过损伤演化模型对疲劳寿命进行预测,预测结果较为准确,均处于1.5倍分散带以内。低应变幅下,低功率试样疲劳源萌生于气孔缺陷,高功率试样疲劳源萌生于表面裂纹,低功率试样裂纹萌生速度明显快于高功率试样,疲劳寿命更低;高应变幅下,试样具有多疲劳源,疲劳寿命明显下降。不同功率试样的裂纹均以穿晶断裂的形式进行扩展。 展开更多
关键词 激光沉积 Ti65钛合金 低周疲劳 循环软化
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激光沉积Ti65钛合金显微组织和疲劳性能
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作者 李晓丹 孙浩军 +4 位作者 殷俊 倪家强 周松 安金岚 张宏杰 《焊接学报》 EI CAS CSCD 北大核心 2024年第10期97-104,共8页
采用单一变量法研究了激光功率和温度对激光沉积制造Ti65钛合金高周疲劳性能的影响,通过光学显微镜、超声波探测仪和扫描电镜(scanning electron microscope,SEM)对试样的显微组织、内部缺陷和断口形貌进行了分析.结果表明,不同功率试... 采用单一变量法研究了激光功率和温度对激光沉积制造Ti65钛合金高周疲劳性能的影响,通过光学显微镜、超声波探测仪和扫描电镜(scanning electron microscope,SEM)对试样的显微组织、内部缺陷和断口形貌进行了分析.结果表明,不同功率试样的显微组织均为网篮组织,α相的含量明显高于β相的含量,高温下网篮组织中的α相发生粗化,晶粒内部出现一些块状α相,组织的均匀性下降.室温和高温条件下高功率和低功率试样的疲劳极限分别为454,398.5,371.5 MPa和336.25 MPa,同一温度下,高功率试样的疲劳极限要比低功率试样的疲劳极限高10%以上;同一功率下,室温试样的疲劳极限要比高温试样的疲劳极限高18%以上,温度对于高周疲劳的影响更大.激光沉积制造Ti65钛合金试样内部存在气孔缺陷,低功率试样中气孔的数目多且直径大,其疲劳源均形核于气孔缺陷处,气孔直径越大,距离表面距离越近,裂纹萌生的越快,疲劳寿命越低,高功率试样中气孔的数目少且直径小,其疲劳源均萌生于表面裂纹,缺陷的存在对裂纹的萌生存在很大影响. 展开更多
关键词 激光沉积 Ti65钛合金 高周疲劳 裂纹萌生
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电流体喷印脉冲电压参数配置对沉积液滴体积的影响
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作者 王鹏 张嘉容 +3 位作者 陈曦 冯天成 张诗雨 刘慧芳 《微纳电子技术》 CAS 2024年第6期158-164,共7页
为了精准控制电流体喷印液滴的最小体积并提高电流体喷印加工的分辨率,研究了电流体喷印的脉冲电压参数配置规律。首先,基于流体力学和电动力学基本原理,分析了喷印过程中泰勒锥的受力情况,并基于此建立了锥射流的体积分数仿真模型,探... 为了精准控制电流体喷印液滴的最小体积并提高电流体喷印加工的分辨率,研究了电流体喷印的脉冲电压参数配置规律。首先,基于流体力学和电动力学基本原理,分析了喷印过程中泰勒锥的受力情况,并基于此建立了锥射流的体积分数仿真模型,探究了初始脉冲电压参数窗口。然后,搭建了电流体喷印平台,通过实验分析发现沉积液滴体积随脉冲电压幅值增大而减小,随脉冲频率的变化不明显,随着脉冲占空比增大,液滴体积先增大后减小。对比了参数配置前后液滴阵列的沉积液滴体积,参数配置前沉积液滴体积为40.89~45.25 nL,参数配置后平均液滴沉积体积为39.54 nL,验证了脉冲电压参数配置规律的有效性,可为节约生产过程中的材料和人工成本,进一步提高微纳电子产品的使用寿命提供参考。 展开更多
关键词 电流体动力学 电流体喷印 沉积液滴体积 脉冲电压 占空比 脉冲频率
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黔北地区下奥陶统沉积相与层序特征 被引量:1
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作者 郭川 张维圆 +1 位作者 付勇 夏鹏 《沉积学报》 CAS CSCD 北大核心 2024年第3期892-911,共20页
【目的】奥陶纪生物大辐射事件(Great Ordovician Biodiversification Event,GOBE)是海洋环境与生物相互作用的结果,通过对该时期碳酸盐台地沉积相和层序的研究可揭示其形成与演化过程及海平面变化历史,并为奥陶纪生物时空分布特征及演... 【目的】奥陶纪生物大辐射事件(Great Ordovician Biodiversification Event,GOBE)是海洋环境与生物相互作用的结果,通过对该时期碳酸盐台地沉积相和层序的研究可揭示其形成与演化过程及海平面变化历史,并为奥陶纪生物时空分布特征及演化规律的探讨提供沉积背景和等时地层格架。【方法】在野外露头剖面实测和显微镜下观察的基础上,识别了黔北地区瓢儿田剖面下奥陶统(桐梓组和红花园组)的岩相类型,进一步分析了沉积模式和高频米级沉积旋回及沉积层序,最后探讨了沉积演化过程中的控制因素。【结果和结论】(1)瓢儿田剖面下奥陶统发育10种岩相类型,主要形成于碳酸盐缓坡沉积体系,且桐梓组和红花园组沉积时期分别以非骨架碳酸盐颗粒和骨架碳酸盐颗粒为特征;(2)桐梓组和红花园组主要发育非对称性的开阔海沉积旋回;(3)识别出3个半三级层序(Sq1~Sq4),每个三级层序均为Ⅱ型层序界面(即岩性转换面)所限。其中Sq1~Sq3为完整的三级层序,由海侵体系域(Transgressive Systems Tract,TST)和海退体系域(Regressive Systems Tract,RST)构成,但Sq4仅发育TST;(4)瓢儿田剖面下奥陶统的沉积演化和层序发育主要受不同级次的相对海平面变化和古地理格局的共同控制。其中不同级次相对海平面波动制约着沉积相的垂向演化,古地理格局则控制着沉积相带的空间分布。 展开更多
关键词 碳酸盐岩 缓坡模式 沉积旋回 沉积层序 相对海平面变化 古地理格局
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Achieving an ion-homogenizing and corrosion-resisting interface through nitro-coordination chemistry for stable zinc metal anodes
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作者 Jizhen Wang Long Jiao +14 位作者 Qiaoyun Liu Wei Xin Yechen Lei Tian Zhang Leixin Yang Dengkun Shu Shuo Yang Kaihua Li Chenyang Li Chao Yi Hongyuan Bai Yuchao Ma Huan Li Wenjun Zhang Bowen'Cheng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期10-18,共9页
Suppression of uncontrollable dendrite growth and water-induced side reactions of Zn metal anodes is crucial for achieving long-lasting cycling stability and facilitating the practical implementations of aqueous Zn-me... Suppression of uncontrollable dendrite growth and water-induced side reactions of Zn metal anodes is crucial for achieving long-lasting cycling stability and facilitating the practical implementations of aqueous Zn-metal batteries.To address these challenges,we report in this study a functional nitro-cellulose interfacial layer(NCIL)on the surface of Zn anodes enlightened by a nitro-coordination chemistry strategy.The NCIL exhibits strong zincophilicity and superior coordination capability with Zn^(2+)due to the highly electronegative and highly nucleophilic nature of the nitro functional group.This characteristic facilitates a rapid Zn-ion desolvation process and homogeneous Zn plating,effectively preventing H_(2) evolution and dendrite formation.Additionally,the negatively charged surface of NCIL acts as a shield,repelling SO_(4)^(2-)anions and inhibiting corrosive reactions on the Zn surface.Remarkably,reversible and stable Zn plating/stripping is achieved for over 5100 h at a current density of 1 mA cm^(-2),which is nearly 30 times longer than that of bare Zn anodes.Furthermore,the Zn/V_(2)O_(5) full cells with the functional interface layer deliver a high-capacity retention of 80.3%for over 10,000 cycles at 5 A g^(-1).This research offers valuable insights for the rational development of advanced protective interface layers in order to achieve ultra-long-lifeZnmetal batteries. 展开更多
关键词 Zinc metal anode Nitro-cellulose interfacial layer Coordination capability Dendrite-free deposition Long-term cycling
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石西至克拉玛依原油管道结蜡特性及安全清管周期研究
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作者 李媛媛 褚楚 +4 位作者 马林君 周良栋 王银强 张添龙 熊小琴 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第3期49-56,共8页
目前含蜡原油管道的清管周期没有统一标准,需要根据油品性质和管道的实际情况确定。采用OLGA软件对石西至克拉玛依原油管道(SK原油管道)的结蜡特性进行了模拟分析,利用浓密膏体的管道输送阻力计算公式,将蜡堵分析转化为蜡柱长度和压降... 目前含蜡原油管道的清管周期没有统一标准,需要根据油品性质和管道的实际情况确定。采用OLGA软件对石西至克拉玛依原油管道(SK原油管道)的结蜡特性进行了模拟分析,利用浓密膏体的管道输送阻力计算公式,将蜡堵分析转化为蜡柱长度和压降关系的计算,制定了SK原油管道的安全清管周期。结果表明:在管道103 km处流体温度降到25℃,从103 km至终点的管段均处于析蜡温度的区间范围;管道运行5天后,采用HeatAnalogy模型模拟的结蜡厚度在110.06 km处达到最大(0.01 mm),结蜡量为80 kg,结蜡量在运行2天后才有明显增加并呈直线上升趋势;以收球筒长度4 m作为蜡柱长度的极限值,计算得到收蜡量为200 kg,推算SK原油管道的清管周期可由目前的5天延长至9天,大大减少了操作成本。结果可为含蜡原油管道的结蜡特性研究及安全清管周期制定提供理论参考。 展开更多
关键词 含蜡原油 结蜡特性 蜡堵分析 清管周期
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多元稀土掺杂YSZ热障涂层的热物理和热循环性能研究
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作者 黄光宏 甄真 +3 位作者 王鑫 牟仁德 何利民 许振华 《真空》 CAS 2024年第2期1-9,共9页
4.5wt.%Gd_(2)O_(3)-5.5wt.%Yb_(2)O_(3)-10.5wt.%Y_(2)O_(3)-79.5wt.%ZrO_(2)(GdYbYSZ)稀土复合氧化物陶瓷是一类适用于更高温度下潜在应用的新型热障涂层(TBCs)材料。采用高温固相合成法制备了GdYbYSZ陶瓷粉体和陶瓷块材,在1 100℃和1... 4.5wt.%Gd_(2)O_(3)-5.5wt.%Yb_(2)O_(3)-10.5wt.%Y_(2)O_(3)-79.5wt.%ZrO_(2)(GdYbYSZ)稀土复合氧化物陶瓷是一类适用于更高温度下潜在应用的新型热障涂层(TBCs)材料。采用高温固相合成法制备了GdYbYSZ陶瓷粉体和陶瓷块材,在1 100℃和1 300℃煅烧不同时间后GdYbYSZ陶瓷粉末无相变,具有非常优异的高温相稳定性。在1 200℃时,GdYbYSZ陶瓷块材的平均热扩散系数和平均热导率分别比同等温度下YSZ陶瓷块材降低了2.1%和5.1%。采用电子束物理气相沉积(EB-PVD)工艺在单晶合金(Ni,Pt)Al粘结层表面制备了GdYbYSZ新型热障涂层。沉积态GdYbYSZ陶瓷涂层的主相结构为立方相,有少量游离态Y_(2)O_(3)和ZrO_(2)共存,其Y和Zr元素的相对含量均比靶材中的高,而Gd和Yb元素含量相当。经1 100℃长期冷热交替循环后,GdYbYSZ陶瓷层表面出现大量规则分布的“泥巴状”微观裂纹,陶瓷层内滋长的横向裂纹已经扩展到陶瓷层与TGO层的界面处,并引起该界面退化分离。陶瓷涂层的剥落位置主要出现在TGO层上下两个临域的界面处。TGO层严重的褶皱、波动起伏、扭曲交联、凸面尖端应力积聚和快速松弛是引起GdYbYSZ/(Ni,Pt)Al热障涂层体系层间界面分离和剥落失效的关键性因素。 展开更多
关键词 电子束物理气相沉积 热障涂层 热物理 热循环 剥落失效
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Yb_(2)O_(3)改性Gd_(2)Zr_(2)O_(7)热障涂层的显微组织和热循环性能研究
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作者 李婷玥 王鑫 +2 位作者 甄真 李娜 许振华 《真空》 CAS 2024年第5期21-29,共9页
(Yb_(0.1)Gd_(0.9))2Zr_(2)O_(7)(YbGdZrO)稀土复合氧化物是适用于更高温度的新型热障涂层(TBCs)候选材料之一。采用电子束物理气相沉积(EB-PVD)工艺在单晶合金(Ni,Pt)Al粘结层表面分别制备了单陶瓷层YbGdZrO和双陶瓷层YbGdZrO/YSZ两种... (Yb_(0.1)Gd_(0.9))2Zr_(2)O_(7)(YbGdZrO)稀土复合氧化物是适用于更高温度的新型热障涂层(TBCs)候选材料之一。采用电子束物理气相沉积(EB-PVD)工艺在单晶合金(Ni,Pt)Al粘结层表面分别制备了单陶瓷层YbGdZrO和双陶瓷层YbGdZrO/YSZ两种热障涂层,并对涂层的相结构、化学组成、显微形貌和热循环行为进行了表征分析。结果表明:沉积态YbGdZrO陶瓷涂层的主相结构为单一的缺陷型萤石相,并有少量Yb_(2)O_(3)共存;与单陶瓷层涂层相比,双陶瓷层涂层的柱状晶簇较为纤细,且可观察到明显的柱状晶间隙;双陶瓷层涂层1100℃热循环寿命约为单陶瓷层涂层的1.5倍;经长期冷热交替循环后,单陶瓷层涂层内横向裂纹滋长,并扩展到YbGdZrO/TGO层界面上方几微米处,导致界面退化分离,且陶瓷层中的Yb元素内扩散进入TGO层;双陶瓷层涂层内出现纵向裂纹,而YbGdZrO/YSZ和YSZ/TGO层间界面基本完好;热循环失效后,单陶瓷层和双陶瓷层试样TGO层内均出现横向和纵向裂纹,甚至进一步诱发了层内断裂分离现象。 展开更多
关键词 电子束物理气相沉积 热障涂层 改性锆酸钆 热循环 界面分离
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基于基因荧光检测的长波通滤光片研制
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作者 林亦心 董新康 +4 位作者 杨宁 辛亚武 祝晗 彭永超 熊仕富 《光电技术应用》 2024年第3期36-41,共6页
光学滤光片是滤去杂质光干扰的重要光学器件,不同波段的滤光片在基因检测得到广泛应用。基于膜系设计理论与薄膜制备工艺,利用电子束蒸发离子辅助沉积技术,以Ta_(2)O_(5)和SiO_(2)为镀膜材料,在JGS1基底玻璃上设计并制备了一种截止中心... 光学滤光片是滤去杂质光干扰的重要光学器件,不同波段的滤光片在基因检测得到广泛应用。基于膜系设计理论与薄膜制备工艺,利用电子束蒸发离子辅助沉积技术,以Ta_(2)O_(5)和SiO_(2)为镀膜材料,在JGS1基底玻璃上设计并制备了一种截止中心λ_(0)=520 nm的高反射,透射带λ为530~750 nm的高透射长波通滤光片。通过分析膜层敏感度和电场分布,设置合理的晶控方案,调整工艺参数,避免监控高敏感膜层时石英晶控灵敏度下降,解决光谱透过率降低的问题。研制的滤光片在520 nm处反射率为99.77%,在530~750 nm波段平均透过率为98.58%,可满足应用需求。 展开更多
关键词 光学薄膜 长波通滤光片 膜堆周期 离子辅助沉积
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