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Machining characteristics of complex prism pattern on electroplated roll by copper 被引量:4
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作者 Tae-Jin JE Sang-Cheon PARK +4 位作者 Kang-Won LEE Yeong-Eun YOO Doo-Sun CHOI Kyung-Hyun WHANG Myung-Chang KANG 《中国有色金属学会会刊:英文版》 CSCD 2009年第B09期288-294,共7页
The BLU (back light unit) is the core component of the LCD for notebook, mobile-phone, navigation, as well as large sized TV, PID (public information display), etc. In order to enhance optical efficiency of LCD, optic... The BLU (back light unit) is the core component of the LCD for notebook, mobile-phone, navigation, as well as large sized TV, PID (public information display), etc. In order to enhance optical efficiency of LCD, optical films with the uniform prism patterns have been used for BLU by stacking two films up orthogonally. In this case, light interference-phenomenon occurred such as Morie, wet-out, u-turning, etc. It caused several problems such as low brightness, spots and stripes in LCD. Recently, the high-luminance micro complex prism patterns are actively studied to avoid the light interference-phenomenon and enhance the optical efficiency. In this study, the roll master to manufacture complex micro prism pattern film was machined by using the high precision lathe. The machined patterns on the roll master were 50, 45, 40, 35, 30, 25, 20, 15, 10 and 5 μm in the pitch with 25.0, 22.5, 20.0, 17.5, 15.0, 12.5, 10.0, 7.5, 5.0 and 2.5 μm in the peak height, respectively. The roll was 2 000 mm in length and 320 mm in diameter. The electroplated roll by copper and the natural single crystal diamond tool was used for machining the patterns. The cutting force was measured and analyzed for each cutting condition by using the dynamometer. The chips and the surfaces after being machined were analyzed by SEM and microscope. 展开更多
关键词 车床加工 微棱镜 铜电镀 特征 光学效率 光学薄膜 笔记本电脑 金刚石工具
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Complex wave excitations general (2+1)-dimensional and chaotic patterns for a Korteweg-de Vries system 被引量:15
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作者 Ma Song-Hua Fang Jian-Ping Zheng Chun-Long 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第8期2767-2773,共7页
Starting from an improved mapping approach and a linear variable separation approach, a new family of exact solutions (including solitary wave solutions, periodic wave solutions and rational function solutions) with... Starting from an improved mapping approach and a linear variable separation approach, a new family of exact solutions (including solitary wave solutions, periodic wave solutions and rational function solutions) with arbitrary functions for a general (2+1)-dimensional Korteweg de solutions, we obtain some novel dromion-lattice solitons, system Vries system (GKdV) is derived. According to the derived complex wave excitations and chaotic patterns for the GKdV 展开更多
关键词 improved mapping approach GKdv system complex wave excitations chaotic patterns
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Mapping Software Metrics to Module Complexity: A Pattern Classification Approach
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作者 Nick John Pizzi 《Journal of Software Engineering and Applications》 2011年第7期426-432,共7页
A desirable software engineering goal is the prediction of software module complexity (a qualitative concept) using automatically generated software metrics (quantitative measurements). This goal may be couched in the... A desirable software engineering goal is the prediction of software module complexity (a qualitative concept) using automatically generated software metrics (quantitative measurements). This goal may be couched in the language of pattern classification;namely, given a set of metrics (a pattern) for a software module, predict the class (level of complexity) to which the module belongs. To find this mapping from metrics to complexity, we present a classification strategy, stochastic metric selection, to determine the subset of software metrics that yields the greatest predictive power with respect to module complexity. We demonstrate the effectiveness of this strategy by empirically evaluating it using a publicly available dataset of metrics compiled from a medical imaging system and comparing the prediction results against several classification system benchmarks. 展开更多
关键词 SOFTWARE Metrics pattern Classification FEATURE Selection SOFTWARE complexITY
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当代语言学关键词·意义单位
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作者 卫乃兴 《外语研究》 北大核心 2026年第2期1-7,112,F0003,共9页
本文系统评述语料库语言学中最具影响力的概念——意义单位,阐述其核心构成、要义及其演变的内在逻辑。简而言之,意义单位这一复杂概念几经表述与修订,已发展为一个系统完整的理论,体现在约翰·辛克莱于20世纪最后20年间相继提出的... 本文系统评述语料库语言学中最具影响力的概念——意义单位,阐述其核心构成、要义及其演变的内在逻辑。简而言之,意义单位这一复杂概念几经表述与修订,已发展为一个系统完整的理论,体现在约翰·辛克莱于20世纪最后20年间相继提出的成语原则模型、扩展意义单位模型以及意义移变单位理论。意义单位理论认为,交际过程中的语言选择是在意义驱动下的词语共选,由此产生大量高频的意义-句法复合体,成为事实上的意义承载单位和文本构建单位,严重挑战了传统语言理论所秉持的“句法主导下的单词自足意义单位”观点。这些理论论证了意义单位的核心构成、不同层面上的词语共选及其结构配置特征,表述了词汇-语法一体、形式-意义同一等重要立场,对人们理解意义传递、语言生成及文本构建具有重要的形塑意义。 展开更多
关键词 成语原则 扩展意义单位 意义移变 意义-句法复合体 形式构型
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全球硒供需格局及贸易网络特征分析
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作者 刘胜前 刘超 +1 位作者 赵汀 梁飞 《中国矿业》 北大核心 2026年第2期20-32,共13页
硒是一种广泛应用于冶金、玻璃、化工、电子、农业及医药健康等领域的稀散元素。本文通过论述全球硒资源的分布、生产、消费、价格特征,并结合复杂网络方法分析全球硒资源贸易格局的演化规律。研究发现,全球硒资源虽然产业规模较小,但... 硒是一种广泛应用于冶金、玻璃、化工、电子、农业及医药健康等领域的稀散元素。本文通过论述全球硒资源的分布、生产、消费、价格特征,并结合复杂网络方法分析全球硒资源贸易格局的演化规律。研究发现,全球硒资源虽然产业规模较小,但在研究期内全球硒产量保持约6.0%的年均速率增长。全球主要硒生产国已经由日本、比利时、德国、加拿大等国家转变为中国、日本、俄罗斯、比利时、芬兰和加拿大等国家,六国产量占全球产量的90.5%,中国硒产量约占全球的48.6%。硒消费重心正加速从传统冶金行业向玻璃、农业及医药健康、光伏薄膜材料、半导体、红外设备、硒基电池及固态电池等新兴产业转移,消费结构正向“高端化、精细化”转变。全球硒贸易量整体呈波动上升趋势,主要进出口国家(地区)集中度高。全球主要的出口国家为比利时、日本、哈萨克斯坦、加拿大、韩国等,进口国家(地区)主要为意大利、中国、中国香港、印度、美国等。哈萨克斯坦、俄罗斯、菲律宾、波兰、芬兰、意大利等国家在全球贸易网络中的地位将逐渐提高,德国、英国在欧洲及全球的硒贸易地位逐渐下降。全球硒贸易团体存在明显的区域特征,整体可分为亚洲社团、欧洲社团、美洲社团和澳洲社团,社团内部区域集中度高。中国应继续巩固其在全球硒贸易市场的主导地位,加强高端硒产品的技术研发,提升产品附加值,避免低价竞争,并且通过多元化资源配置提高硒资源供应链的稳定性和安全性。 展开更多
关键词 复杂网络 消费结构 贸易格局 战略性矿产
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基于经脉-脏腑理论运用复杂网络分析针灸治疗卵巢早衰经-穴规律及其机制
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作者 杜东玲 饶钰湘 +2 位作者 唐华丽 唐欢 章薇 《广州中医药大学学报》 2026年第2期414-424,共11页
【目的】基于复杂网路技术探索针灸治疗卵巢早衰全阶段的经-穴规律及相关经脉-脏腑作用靶点。【方法】计算机检索中国期刊全文数据库(CNKI)、万方数据知识服务平台(Wanfang)、维普中文科技期刊数据库(VIP)、中国生物医学数据文献库(Sino... 【目的】基于复杂网路技术探索针灸治疗卵巢早衰全阶段的经-穴规律及相关经脉-脏腑作用靶点。【方法】计算机检索中国期刊全文数据库(CNKI)、万方数据知识服务平台(Wanfang)、维普中文科技期刊数据库(VIP)、中国生物医学数据文献库(SinoMed)、美国生物医学信息检索系统(PubMed)、科学网(Web of science)等各大数据库。检索自各数据库建库以来至2025年3月收录的针灸治疗卵巢早衰全阶段的临床研究及动物实验研究文献。采用Microsoft Excel 2021统计临床研究文献的腧穴频次、归经等,应用SPSS Modeler 18.0软件进行关联规则分析并绘制复杂网络图。统计动物实验文献中相关腧穴及靶点,用人类基因数据库(GeneCards)提取后绘制Venny图获取交集靶点,绘制蛋白互作网络图(PPI),对关键靶点进行基因(GO)本体分析和京都基因与基因组百科全书(KEGG)生物通路富集分析。通过交集分析获取核心腧穴,提取核心腧穴相关性高的靶点,构建经脉-腧穴-靶点-疾病网络。【结果】共纳入224篇临床研究类文献,高频腧穴为关元、三阴交、子宫等。腧穴归经以任脉、足太阳膀胱经等为主。纳入52篇动物实验类文献,筛选出38个与针灸治疗卵巢早衰相关的核心靶点,其机制可能与抗凋亡蛋白(BCL2L1)、c-Jun氨基酸末端激酶(MAPK8)、哺乳动物雷帕霉素靶蛋白(mTOR)等核心靶点有关。通过GO及KEGG富集分析得到203条相关生物学过程、97条相关通路。【结论】针灸治疗卵巢早衰涉及多条经脉、腧穴,其核心腧穴为关元、三阴交、子宫、肾俞、足三里、太冲、太溪。针灸可能通过多靶点、多功能、多通路治疗卵巢早衰,BCL2L1、MAPK8、mTOR、KEAP1、CCND1可能为潜在核心靶点。 展开更多
关键词 针灸 卵巢早衰 选穴规律 复杂网络 经脉-脏腑理论 机制分析 关元 三阴交 子宫 核心靶点
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基于复杂网络分析的复发性流产选穴规律与证-穴关系研究
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作者 吕天宜 马尘 +3 位作者 李宁 何丹丹 刘丹 武颖 《世界中西医结合杂志》 2026年第1期160-167,共8页
目的针灸在治疗复发性流产(Recurrent spontaneous abortion,RSA)领域已得到较为广泛的应用,但缺少对RSA选穴规律及相对应的证-穴关系的高质量总结。文中通过复杂网络分析技术进行系统性总结,为临床精准施治提供参考。方法检索中国知网(... 目的针灸在治疗复发性流产(Recurrent spontaneous abortion,RSA)领域已得到较为广泛的应用,但缺少对RSA选穴规律及相对应的证-穴关系的高质量总结。文中通过复杂网络分析技术进行系统性总结,为临床精准施治提供参考。方法检索中国知网(CNKI)、万方数据(Wanfang Data)、维普期刊资源整合服务平台(VIP)、中国生物医学文献数据库(SinoMed)、PubMed、Embase和Web of Science中针灸治疗RSA的相关文献,构建核心腧穴处方表与证型-腧穴处方表,统计腧穴频次、频率、腧穴归经、腧穴分布、证-穴关系。使用SPSS Modeler软件进行关联规则分析;采用Cytoscape软件绘制复杂共现网络图谱;运用R语言判断最佳聚类数,对高频腧穴实现聚类分析。结果共纳入40篇文献,记录核心腧穴处方共46条,证型-腧穴处方共33条。频次分析结果显示,关元、足三里、三阴交、子宫、气海是临床治疗RSA最常用的穴位。频率分析结果提示,排名前10的穴位累计使用频率为56.21%,是针灸治疗RSA的常用腧穴。任脉为主要归经,腹部是腧穴分布的主要部位。证-穴关系提示,常见辨证分型为肾虚血瘀证、脾肾两虚证、肾气不足证。三阴交、太溪是肾虚血瘀证的常用腧穴;足三里、关元是脾肾两虚证的常用腧穴;命门、关元是肾气不足证的常用腧穴。关联规则分析发现,关元-足三里、关元-子宫、关元-气海的出现频次与支持度最高,为高频配伍腧穴。网络共现分析发现,关元、足三里、命门、肾俞是治疗的核心穴位。高频腧穴可分为3个有效聚类群。结论针灸治疗RSA的核心处方为关元、足三里、三阴交、子宫、气海、命门、肾俞,临床应在核心处方的基础上根据不同证型选择配穴。 展开更多
关键词 复发性流产 复杂网络分析 选穴规律 证-穴关系 R语言
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Wavelet packet-based identification of complex oscillation in biological signals 被引量:5
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作者 Zhang Shuqing Sarah K. Spurgeon +3 位作者 Zhang Liguo Jin Mei John A. Twiddle Femando S. Schlindwein 《仪器仪表学报》 EI CAS CSCD 北大核心 2008年第2期225-232,共8页
Owing to the intrinsic nonlinearities of the system,a contracting mechanism,such as myogenic response,may induce different oscillatory patterns.Many specialists discussed the relations of oscillatory patterns with int... Owing to the intrinsic nonlinearities of the system,a contracting mechanism,such as myogenic response,may induce different oscillatory patterns.Many specialists discussed the relations of oscillatory patterns with intrinsic control system or some pathological condition,but there is no single,well-defined criterion to achieve the identification of regular,stochastic,and chaotic activities.In this paper,we focus on the Mallat algorithm of wavelet packet and use it in the identification of the regular periodic,stochastic,and chaotic fluctuations.According to the specific frequency configuration of the chaos activity,we select proper layers of decomposition of wavelet packet and did fine segments to the frequency of signals.The frequency band of energy convergence could be recognized.The signal of periodic,stochastic,and chaotic could be distinguished depending on it.Numerical experiment is given to show its efficiency.Experiments on 12 babies' lung data have been done.This identification by means of wavelet packet could support the cardiologist or cerebral specialist to do more observation and deeper analysis to physic signals. 展开更多
关键词 复振荡 生物信号 鉴别模式 不规则波动 微波
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The characteristic target-pattern regional ore zonality of the Nanling region,China(Ⅲ) 被引量:1
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作者 Chongwen Yu 《Geoscience Frontiers》 SCIE CAS 2011年第4期551-569,共19页
By applying the 'theory of synchronization' from the science of complexity to studying the regional regularity of ore formation within the Nanling region of South China,a characteristic target-pattern regional ore z... By applying the 'theory of synchronization' from the science of complexity to studying the regional regularity of ore formation within the Nanling region of South China,a characteristic target-pattern regional ore zonality has been discovered.During the early and late Yanshanian epoch (corresponding respectively to the Jurassic and Cretaceous periods),two centers of ore formation emerged successively in the Nanling region;the former is mainly for rare metals(W,Sn,Mo,Bi,Nb) and one rare-earth element(La) and was generated in the Jurassic period;whereas the latter is mainly for base metals (Cu,Pb,Zn,Sb,Hg),noble metals(Au,Ag),and one radioactive element(U) and was generated in the Cretaceous period.Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province.The characteristic giant nonlinear target-pattern regional ore zonality was generated respectively from the two centers of ore formation by the spatio-temporal synchronization process of the Nanling complex metallogenic system.It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality.Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures.Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution.The integral successive processes of synchronization-dynamical clustering-phase dynamics accomplished the regional ore zonality by way of "multiple field dynamics" of spatio-temporal superposition of multiple coupled pulsatory solitary wave trains of the zonal sequences of different ores.A new methodology for revealing regional ore zonality is developed,which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization. 展开更多
关键词 Ore zonality Target pattern Synchronization complexity Jurassic/Cretaceous NANLING
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The characteristic target-pattern regional ore zonality of the Nanling region,China(Ⅱ) 被引量:2
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作者 Chongwen Yu 《Geoscience Frontiers》 SCIE CAS 2011年第3期323-347,共25页
By applying the 'theory of synchronization' from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional or... By applying the 'theory of synchronization' from the science of complexity to studying the regional regularity of ore formation within the Nanling region of southern China, a characteristic targetpattern regional ore zonality has been discovered. During the early and late Yanshanian epoch (corresponding respectively to the Jurassic and Cretaceous periods), two centers of ore formation emerged successively in the Nanling region; the former is mainly for rare metals (W, Sn, Mo, Bi, Nb) and one rare-earth element (La) and was generated in the Jurassic period; whereas the latter is mainly for base metals (Cu, Pb, Zn, Sb, Hg), noble metals (Au, Ag), and one radioactive element (U) and was generated in the Cretaceous period. Centers of ore formation were brought about by interface dynamics respectively at the Qitianling and Jiuyishan districts in southern Hunan Province. The characteristic giant nonlinear target-pattern regional ore zonality was generated by spatio-temporal synchronization process of the Nanling complex metallogenic system. It induced the collective dynamics and cooperative behavior of the system and displayed the configuration of the regional ore zonality. Then dynamical clustering transformed the configuration into rudimentary ordered coherent structures. Phase dynamics eventually defined the spatio-temporal structures of the target-pattern regional ore zonality and determined their localization and distribution. A new methodology for revealing regional ore zonality is developed, which will encourage further investigation of the formation of deep-seated ore resources and the onset of large-scale mineralization. 展开更多
关键词 Rare elements Ore zonality Target pattern Synchronization complexity Jurassic/Cretaceous NANLING China
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NUMERICAL STUDIES FOR A MODEL DESCRIBING COMPLEXITY
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作者 黄欣 刘曾荣 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1994年第8期767-770,共4页
A simple model based on the discussion for infinite dimensional system is introduced to investigate the dynamical complexity for continous system.By using numerical. methods,we show the dynamical behaviors of the maod... A simple model based on the discussion for infinite dimensional system is introduced to investigate the dynamical complexity for continous system.By using numerical. methods,we show the dynamical behaviors of the maodel model appear tocorrespond to universal language and context-senitive language. 展开更多
关键词 complexity. evolution of pattern numerical method
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Visitor flow pattern of Expo 2010 被引量:1
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作者 樊超 郭进利 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第7期66-73,共8页
Expo 2010 Shanghai China was a successful, splendid, and unforgettable event, leaving us with valuable experi- ences. The visitor flow pattern of the Expo is investigated in this paper. The Hurst exponent, the mean va... Expo 2010 Shanghai China was a successful, splendid, and unforgettable event, leaving us with valuable experi- ences. The visitor flow pattern of the Expo is investigated in this paper. The Hurst exponent, the mean value, and the standard deviation of visitor volume indicate that the visitor flow is fractal with long-term stability and correlation as well as obvious fluctuation in a short period. Then the time series of visitor volume is converted into a complex network by using the visibility algorithm. It can be inferred from the topological properties of the visibility graph that the network is scale-free, small-world, and hierarchically constructed, confirming that the time series are fractal and a close relationship exists among the visitor volumes on different days. Furthermore, it is inevitable that will be some extreme visitor volumes in the original visitor flow, and these extreme points may appear in a group to a great extent. All these properties are closely related to the feature of the complex network. Finally, the revised linear regression is performed to forecast the next-day visitor volume based on the previous 10-day data. 展开更多
关键词 fractal pattern time series visibility graph complex network
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THE FORMABILITY OF COMPLEX FLOURIDE COMPOUNDS
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作者 LI Zheng LIU Honglin +1 位作者 CHENG Zhaonian CHEN Nianyi, Shanghai Institute of Metallurgy, Academia Sinica, Shanghai, ChinaZHOU Jiaju, Institute of Chemical Metallurgy, Academia Sinica, Beijing, China CHEN Nianyi, Professor, Shanghai Institute of Metallurgy, Academia Sinica, Shanghai 200050, China 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1992年第7期74-76,共3页
The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic char... The formability of complex flourides has been studied by chemical bond parameter-pattern recognition method. In a multi-dimensional space spanned by ionic radius, ionic polarizability, electronegativity and ionic charge of the metal elements, the binary complex flouride-forming systems and binary flouride systems without complex flouride formation distribute in different regions with a clear-cut boundary. The mathematical models obtained are useful for new complex flouride predicton. 展开更多
关键词 complex flouride compound prediction pattern recognition
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复杂网络视角下世界粮食贸易网络脆弱性研究 被引量:3
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作者 韩建军 崔欣苗 +2 位作者 侯婧祎 程玉 张佳豪 《粮油食品科技》 北大核心 2025年第2期198-205,共8页
为探究世界粮食贸易网络的脆弱性,为国际粮食贸易市场做出合理预判提供参考,基于1990—2020年的世界粮食贸易数据,结合复杂网络理论与脆弱性理论,从模体的角度探究世界粮食贸易网络局部结构脆弱性变化情况,并模拟世界粮食贸易网络在随... 为探究世界粮食贸易网络的脆弱性,为国际粮食贸易市场做出合理预判提供参考,基于1990—2020年的世界粮食贸易数据,结合复杂网络理论与脆弱性理论,从模体的角度探究世界粮食贸易网络局部结构脆弱性变化情况,并模拟世界粮食贸易网络在随机攻击和蓄意攻击模式下的失效过程,将网络中的节点分级。结果表明:世界粮食贸易网络的局部结构中,V型结构占比较高,网络的稳定性较弱,但这种现象有减缓趋势;对比真实网络与随机网络,真实网络的结构更加稳定且贸易关系更复杂;世界粮食贸易网络在面对随机攻击时具有良好的强韧性,面对蓄意攻击时表现出较强的脆弱性,蓄意攻击对网络的破坏力远大于随机攻击;在蓄意攻击模式下,世界粮食贸易网络的节点根据失效过程可以分为三个层级,其中第一层级节点对网络稳定性影响最大。 展开更多
关键词 粮食安全 世界粮食贸易 复杂网络 脆弱性 格局与趋势
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全球稀土金属贸易网络格局演变与供应危机传播研究 被引量:2
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作者 廖秋敏 谢柳燕 +1 位作者 韩嘉雯 张晓瑶 《中国矿业》 北大核心 2025年第6期26-37,共12页
稀土是航空航天、新能源、新材料、生物医药等领域的重要基础材料。2012年后全球稀土金属(HS280530)贸易量大幅增长,贸易网络主体结构发生明显的转变,贸易网络不稳定,全球稀土金属贸易存在一定的供应危机。为深入研究全球稀土金属贸易... 稀土是航空航天、新能源、新材料、生物医药等领域的重要基础材料。2012年后全球稀土金属(HS280530)贸易量大幅增长,贸易网络主体结构发生明显的转变,贸易网络不稳定,全球稀土金属贸易存在一定的供应危机。为深入研究全球稀土金属贸易网络格局演变、供应危机传播路径及影响程度,本研究构建了2002—2022年全球稀土金属贸易网络和级联失效(雪崩)模型,深入分析全球稀土金属贸易格局转变和贸易流向变化,模拟了参数r_(1)=5、r_(2)=5、r_(3)=7时不同爆发源的雪崩规模、雪崩轮次和危机传播路径。研究发现:①2002—2022年间,全球稀土金属贸易的规模、平均度和集中度均有所增加,核心国家数量增多,除中国稀土金属出口量一直稳居前四位外,其他排名变动频繁,到2022年全球稀土金属出口量排名前四位的国家多为亚洲国家;②随着全球稀土金属贸易网络愈加稳定,供应危机的影响范围逐渐缩小,但中国间接传染依然比直接传染的国家(地区)更多;③中国和美国的贸易规模减小,但供应危机传播时间均变长。中国发生供应危机影响的程度有所降低,美国存在小幅增长。中国对欧洲的供应危机传播规模最大、传播时间最长。日本在2002年的危机影响规模较大,供应危机的雪崩规模随时间变化逐渐减小,到2022年其发生供应危机只会影响菲律宾。该研究有利于为维护全球稀土金属贸易稳定和采取防范措施缓解供应危机提供参考。 展开更多
关键词 稀土金属 复杂网络 贸易格局 供应危机 级联失效
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Dispersal Patterns of the Late Cretaceous to Early-Tertiary Sediments in the Southern Anambra Basin, Southeastern Nigeria
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作者 Samuel O. Onyekuru Chukwuma J. Iwuagwu +2 位作者 Godwin I. Nwankwor Nathaniel N. Onu Cyril E. Ukaonu 《International Journal of Geosciences》 2013年第3期588-604,共17页
The dispersal patterns of the Late Cretaceous to Early Tertiary sediments in southern Anambra Basin were studied to delineate spatial facies distributions for improved mapping and hydrocarbon prospectivity. Seven lith... The dispersal patterns of the Late Cretaceous to Early Tertiary sediments in southern Anambra Basin were studied to delineate spatial facies distributions for improved mapping and hydrocarbon prospectivity. Seven lithofacies distinguished from eleven outcrop sections aided the interpretation of depositional environments for the different depositional units. Interpreted paleoenvironments ranged from estuarine/lagoonal to tidal delta and shallow marine depositional environments. Sequence stratigraphic interpretation of the deposits using vertical relationships between the delineated facies and foraminiferal and palynofacies assemblages and the interpreted environmental setting identified two complete sequences (SEQ-1 and -2) and two incomplete sequences (SEQ-3 and -4) in the study area. The sequiences are enveloped by three Type-1 Sequence Boundaries (SB), two Transgressive Surfaces of Erosion (TSE) and four Maximum Flooding Surfaces (MFS). The identified surfaces were used to delineate formation boundaries and as such would assist in the improved mapping of the Anambra Basin and adjoining depocenters. The massive sand units of the Highstand and Transgressive Systems Tracts constitute good (potential) reservoirs, while the transgressive shales would constitute seals for potential traps in the study area. The delineation of these petroleum system elements, especially those associated with the Transgressive and Highstand Systems Tracts has conferred great hydrocarbon prospectivity potential on the sedimentary sequences in the Basin. The absence of deep marine and slope complexes of the Lowstand Systems Tract (LST) in the interpreted sequences is indicative that the study area is the up-dip section of the Anambra Basin. 展开更多
关键词 Dispersal patterns Formation Sequence Boundary FACIES Spatial complexes Erosion
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Fabrication of Copper Wire Using Glyoxylic Acid Copper Complex and Laser Irradiation in Air 被引量:1
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作者 Tomoji Ohishi Ryutaro Kimura 《Materials Sciences and Applications》 2015年第9期799-808,共10页
Preparation of a glyoxylic acid copper complex and fabrication of fine copper wire by CO2 laser irradiation in air to a thin film of that complex have been investigated. Irradiating laser to the complex thin film spin... Preparation of a glyoxylic acid copper complex and fabrication of fine copper wire by CO2 laser irradiation in air to a thin film of that complex have been investigated. Irradiating laser to the complex thin film spin-coated on a glass substrate, thin film of metallic copper was fabricated in areas that were subjected to laser irradiation in air. The thickness of this thin copper film was approx. 30 to 40 nm, and as non-irradiated areas were etched and removed by a soluble solvent of the copper complex, fine copper wire with 200 μm width was formed by laser direct patterning. The resistivity of this thin copper film depended on the irradiation intensity of the laser and was 3.0 × 10–5 Ω·cm at 12 W intensity (sweep speed: 20 mm/s). This method enables the high-speed deposition of copper wiring in air by a printing process, indicating an inexpensive and useful process for fabricating copper wiring. 展开更多
关键词 Glyoxylic ACID COPPER complex CO2 LASER FINE COPPER Wire LASER Direct patternING Printable ELECTRONICS
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浅薄层超稠油高效开发技术研究及应用 被引量:1
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作者 卢迎波 孙新革 +1 位作者 赵长虹 胡鹏程 《中国科技论文》 2025年第2期95-105,共11页
新疆超稠油资源丰富,由于储层条件、流体性质等因素制约,浅薄层超稠油热采机理、开发模式、高温工艺、智能低碳运行面临一系列重大科技挑战。为此,在国内外稠油开发技术发展的基础上,以研究区近物源辫状河沉积、浅薄层砂砾岩超稠油油藏... 新疆超稠油资源丰富,由于储层条件、流体性质等因素制约,浅薄层超稠油热采机理、开发模式、高温工艺、智能低碳运行面临一系列重大科技挑战。为此,在国内外稠油开发技术发展的基础上,以研究区近物源辫状河沉积、浅薄层砂砾岩超稠油油藏为目标,提出了浅薄层超稠油亟待创新的驱泄复合理论方法、立体井网开发方式、高温高压工艺体系和智能低碳运行模式等重大技术问题。研究结果表明:1)物模实验揭示了“近端蒸汽驱替、远端重力泄油”机理,实现了8~15m薄层超稠油高效动用;2)在“直-平”点线和“平-平”线线井网基础上,开展水平井暂堵微压裂和不同阶段精细调控,注蒸汽波及系数为0.9,采收率达55%以上;3)配套研发的注采两用柔性泵、动态化学屏蔽工艺及作业装备能够实现油井生产时率提升15%,保障了浅层高温下蒸汽腔低伤害安全作业;4)通过智能配汽工艺管柱,全密闭集输处理装置和地下与地面协同云平台决策系统研发,系统热效率提高11.6%,年减少碳排放21.9万t。随着技术定型和推广应用,已形成中国浅薄层超稠油开发“样本”,为国内外稠油高效开发提供思路和技术借鉴。 展开更多
关键词 浅薄层超稠油 驱泄复合 立体井网 智能低碳 采收率 辫状河
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Preparation and Properties of Copper Fine Wire on Polyimide Film in Air by Laser Irradiation and Mixed-Copper-Complex Solution Containing Glyoxylic Acid Copper Complex and Methylamine Copper Complex 被引量:2
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作者 Tomoji Ohishi Naoki Takahashi 《Materials Sciences and Applications》 2018年第11期859-872,共14页
Formation of copper wiring on a polyimide film by laser irradiation to a stable copper-complex film consisting of glyoxylic acid copper complex and methylamine copper complex in air has been investigated. A stable met... Formation of copper wiring on a polyimide film by laser irradiation to a stable copper-complex film consisting of glyoxylic acid copper complex and methylamine copper complex in air has been investigated. A stable metallic copper on the polyimide film was precipitated even in air. Since this copper was generated only in the laser-irradiated parts, direct patterning of copper wiring was possible. It was also found that copper was precipitated by electroless copper plating on the laser-deposited copper wiring and it was possible to thicken the copper wiring by this precipitation. The resistivity of the copper wiring was almost the same as that of the bulk of metallic copper. The developed method—combining laser irradiation to a copper-complex-coated film and electroless copper plating—enables the high-speed deposition of fine copper wiring on a polyimide film in air by a printing process, indicating an inexpensive and useful process for fabricating copper wiring without high vacuum facility and heat-treatment under inert gas. 展开更多
关键词 Glyoxylic Acid COPPER complex CO2 LASER Fine COPPER Wire LASER Direct patternING POLYIMIDE Film Printable Electronics
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全球稀土氧化物贸易格局演变与供应风险传播研究:基于SIR模型
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作者 廖秋敏 张佳乐 熊斌斌 《中国矿业》 北大核心 2025年第10期44-56,共13页
稀土是广泛应用于高新技术领域的重要战略资源。随着地缘政治摩擦与大国博弈日趋加剧,稀土氧化物产品的全球贸易安全受到潜在威胁,供应风险随时可能发生。贸易网络结构特征及演变趋势也深刻影响着供应风险的传导路径与传播范围。为精准... 稀土是广泛应用于高新技术领域的重要战略资源。随着地缘政治摩擦与大国博弈日趋加剧,稀土氧化物产品的全球贸易安全受到潜在威胁,供应风险随时可能发生。贸易网络结构特征及演变趋势也深刻影响着供应风险的传导路径与传播范围。为精准识别关键风险源并评估其潜在影响,选取2003—2023年稀土氧化物贸易数据,运用复杂网络理论系统分析全球贸易结构演变特征;构建关键风险节点识别框架与SIR传播模型,基于2023年数据模拟不同风险源供应风险传播状况。研究结果表明:①从贸易格局演变来看,全球稀土氧化物贸易规模和网络密度逐步提升,贸易网络呈现明显的小世界特征,贸易集中度整体上呈现“W”型的变化趋势,贸易格局由中国主导逐渐转向对少数国家(地区)的依赖,中国在稀土氧化物进口方面对美国高度依赖。②从关键风险节点识别来看,资源禀赋型风险源主要集中于中国、美国、马来西亚和荷兰等出口大国;而贸易中介型风险源则多见于在全球网络中担任转口或中介角色的国家(地区),如荷兰、日本、印度和德国。③从网络供应风险传播来看,中美两国的风险传播规模最大,且美国的传播轮次最多。其中,只有美国的供应短缺能引发中国的稀土氧化物供应危机。④恢复能力的提升能够有效减缓风险的传播。研究有助于揭示稀土贸易中的潜在风险因素及其影响范围,为构建更加安全、稳定的全球稀土供应体系提供理论支撑。 展开更多
关键词 稀土氧化物 复杂网络 贸易格局 风险节点识别 风险传播 SIR模型
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