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Systematic analysis of elemental flow patterns during thermal runaway in traction lithium-ion batteries
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作者 Huaibin Wang Qinzheng Wang +8 位作者 Xu Gong Chengshan Xu Changyong Jin Yong Peng Yang Li Yongbin Yang Jing Feng Kai Shen Xuning Feng 《Journal of Energy Chemistry》 2025年第5期20-27,共8页
As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,... As lithium-ion batteries(LIBs)continue to evolve toward lower costs and higher energy densities,their potential safety risks have become increasingly apparent.Incidents such as explosions at energy storage facilities,fires in electric vehicles,and building fires ignited by charging two-wheeled vehicles have been occurring with alarming frequency,often resulting in significant casualties and injuries.Conducting indepth investigations into thermal runaway(TR)incidents in LIBs can significantly reduce the risk of future occurrences.However,current investigations into LIB fire and explosion incidents face challenges due to the difficulty of conducting in-depth analyses and the lack of a robust theoretical framework to guide these investigations.To enhance the effectiveness of in-depth investigations into battery fire and explosion incidents and to address the lack of theoretical guidance,this paper is the first to systematically examine the conservation and flow patterns of elements during the TR process of LIBs.The analysis reveals that during TR,the gas products generated include approximately 1.5 g of H_(2),23.6 g of CO,88.4 g of CO_(2),8.9 g of C_(2)H_(4),7.3 g of CH_(4),3.7 g of C_(2)H_(6),and 82 g of electrolyte vapor.After TR,the solid compounds formed consist of approximately 2.5 g of LiF,29–92.2 g of elemental Ni/Co/Mn,11.4 g of Li_(2)CO_(3),200.6 g of graphite,1.4 g of NiO,29.6 g of MnO,30.1 g of CoO,67 g of elemental Cu,0.03 g of LiNiO_(2),and 4.3 g of LiAlO_(2).Importantly,the energy released from reactions forming solid compounds during TR surpasses that from gas-forming reactions.This investigation represents the first application of Hess’s law to verify the conservation of elements during the TR process of lithium-ion batteries.The proposed methodology is also applicable to other types of energy storage batteries,effectively advancing techniques for comprehensively investigating lithium battery fire and explosion incidents. 展开更多
关键词 Battery Safety Energy Storage Thermal runaway Accident investigation elemental Flow pattern
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Reflections on the Integration of Folk Pattern Elements into the Design of Architectural Art
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作者 Yajuan Liu 《Journal of World Architecture》 2025年第2期41-48,共8页
In the production and life of ancient Chinese folk artists,through the abstract and geometric arrangement of things,they formed many meaningful patterns.These patterns are widely used in a variety of decorations,refle... In the production and life of ancient Chinese folk artists,through the abstract and geometric arrangement of things,they formed many meaningful patterns.These patterns are widely used in a variety of decorations,reflecting the most simple artistic ideas in the life of the working people,and are also an important embodiment of folk art aesthetics.Many elements of folk patterns have been preserved to this day,and they have an important role in inspiring and guiding today’s art design.This paper mainly analyzes the folk pattern elements and their artistic value,and elaborates on the application of folk pattern elements in architectural design and the specific design methods,to provide certain references for the combination of modern architectural design and traditional folk patterns. 展开更多
关键词 Folk pattern elements Architectural design VALUE
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Transport patterns of micro nutrient elements from the continental shelf of the East China Sea to the Kuroshio area
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作者 Lu Saiying, Yao Qiao’er and Chen Zhen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1992年第2期219-230,共12页
On the basis of the in situ data of DO2, pH, SiO2. PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.1.The inorgonic nutrients are obviousl... On the basis of the in situ data of DO2, pH, SiO2. PO4-P, NO3-N and NO2-N collected in the north of the East China Sea during 1987-1988, the following points are mainly expounded.1.The inorgonic nutrients are obviously affected by continent runoff in the north of the East China Sea. Their distributions are characteristic of its distribution of terrigenous materials.2.There are three transport paths of nutrients from the shelf to the Kuroshio area. The first is mixing-diffusing-advec-tion and upwelling process, the process of biology and biochemistry belongs to the second, and the sinking process is the last one.3.The swing of the Kuroshio axis affectes both the range of the migration of substances through mixing-diffusing-advec-tion process and the upwelling degree of the subsurface Kuroshio water to the shelf.4.Most part of the substances sink as macroparticles to the deep layer before reaching the Kuroshio area. 展开更多
关键词 Transport patterns of micro nutrient elements from the continental shelf of the East China Sea to the Kuroshio area
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喜马拉雅造山带现今汇聚模式的数值模拟
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作者 田镇 于鑫 +2 位作者 李振洪 马星宇 王师迪 《地球物理学报》 北大核心 2026年第3期1018-1033,共16页
自~55 Ma以来,印度大陆与欧亚大陆的持续挤压、碰撞,使得喜马拉雅造山带成为了全球地壳运动最强烈、构造机理最复杂的地区之一,对其变形模式与动力机制的研究历来是地学界的前沿与热点.目前,虽已有部分研究初步解释了造山带局部的形变特... 自~55 Ma以来,印度大陆与欧亚大陆的持续挤压、碰撞,使得喜马拉雅造山带成为了全球地壳运动最强烈、构造机理最复杂的地区之一,对其变形模式与动力机制的研究历来是地学界的前沿与热点.目前,虽已有部分研究初步解释了造山带局部的形变特征,但基于区域动力背景与流变特性的精细动力学模拟仍较为匮乏,喜马拉雅弧整体的地壳汇聚模式仍存在较大争议.基于此,本文以喜马拉雅造山带震间GNSS速度场为约束,采用三维有限元数值模拟方法,建立了造山带径向汇聚、斜向汇聚以及黏弹性汇聚等动力学模型,揭示了喜马拉雅现今的形变机制与动力模式.结果显示:相比于径向汇聚模型,斜向汇聚模型的预测值与GNSS观测值的拟合度更高,说明了印度板块与青藏高原的汇聚既存在着径向运动(速率为18 mm·a^(−1)),还存在着与弧平行的运动(中段2 mm·a^(−1)、东段14 mm·a^(−1)).因此本文认为青藏高原南部广泛存在的拉张裂谷的构造动力很可能来源于印度—欧亚板块沿边界断裂所发生的斜向汇聚,这与重力垮塌或岩石圈地幔对流等假说有着一定的差异.另一方面,相比于弹性汇聚模型,考虑区域流变特性的黏弹性汇聚模型对远场GNSS观测值的拟合度更高,说明区域构造应力很可能引发了远场稳定的黏弹性变形,也意味着黏弹性的地学模型能够更精细、更合理地模拟造山带的动力过程.此外,黏弹性模型所估计的边界断裂闭锁深度为16 km,略低于弹性模型的结果.上述研究工作有助于我们从数值模拟角度全面、深刻地理解喜马拉雅现今可能的变形模式与板块汇聚机制. 展开更多
关键词 喜马拉雅造山带 有限元模拟 汇聚模式 黏弹性介质 动力学机制
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系统辨证脉学脉诊技术规范
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作者 齐向华 滕晶 +4 位作者 闫伟 史俍元 康晨 丁晓 李甲民 《山东中医杂志》 2026年第2期117-121,共5页
系统辨证脉学是遵循系统论的基本原理和基本规律,融合临床经验,形成的具有独到见解、容纳多学科、涵盖多层面的全新脉学体系,其注重手指感觉功能的开发和分化、各种脉象要素感觉“情景记忆系统”的建立以及疾病过程中客观“证据链”的诊... 系统辨证脉学是遵循系统论的基本原理和基本规律,融合临床经验,形成的具有独到见解、容纳多学科、涵盖多层面的全新脉学体系,其注重手指感觉功能的开发和分化、各种脉象要素感觉“情景记忆系统”的建立以及疾病过程中客观“证据链”的诊查,具有系统、科学、规范、实用和易操作等特点。然而操作规范的缺失阻碍了系统辨证脉学脉诊技术的临床推广应用和进一步创新发展。文章结合现有研究成果、系统辨证脉学相关书籍和专家共识等,从切脉、识脉、审脉等方面对系统辨证脉学脉诊技术进行了规范,旨在推动系统辨证脉学脉诊技术的普及推广与创新发展。 展开更多
关键词 系统辨证脉学 脉象要素 切脉 识脉 审脉
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龙骨质量评价研究
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作者 王云云 孙媛 +3 位作者 刘小辉 李赫宇 郑国华 李娟 《中华中医药学刊》 北大核心 2026年第1期159-165,I0022,I0023,共9页
目的为探索龙骨药材性状、理化特征、物相组成与元素含量之间的关联性,建立基于“辨状论质”理论的龙骨质量多维度科学评价体系。方法通过查阅历代本草及现代文献等对龙骨品质评价特征的记载,整理和归纳出其品质评价要点。此外,收集龙... 目的为探索龙骨药材性状、理化特征、物相组成与元素含量之间的关联性,建立基于“辨状论质”理论的龙骨质量多维度科学评价体系。方法通过查阅历代本草及现代文献等对龙骨品质评价特征的记载,整理和归纳出其品质评价要点。此外,收集龙骨样品36批,通过性状鉴定方法进行初步鉴别,利用X射线衍射荧光(XRD)技术分析物相组成,并且检测性状鉴别相关的理化指标,包括吸湿率、色差值和荧光等。同时,采用电感耦合等离子体发射光谱仪(ICP-OES)技术检测元素含量,通过统计分析和计量学方法研究龙骨性状特征与内在质量的相关性,并建立“性状指标-成分含量”预测模型。结果龙骨药材质地、外观特征色泽、吸湿性和荧光等特征可作为龙骨真伪鉴别、质量优劣的指标。含量测定显示,龙骨Ca和P的含量较高,其次为Mg、Fe和Al。物相分析显示龙骨主要含氟磷灰石和方解石。色差值亮度(L)与Ca、P正相关,吸湿性与P、Sr含量正相关。龙骨合格品满足Ca和P的比例均大于2∶1,氟磷灰石≥30.0%,且Ca≥30.00%,P≥7.00%,L值≥35.00,吸湿率≥1.00%。结论研究基于“辨状论质”建立龙骨元素和物相成分指标。同时建立“性状指标-成分含量”预测模型,经检验预测值与实际值相近,模型预测效果优良。基于传统“辨状论质”理论可较为准确地预测龙骨药材的质量,为龙骨药材质量标准的完善提供了科学基础。 展开更多
关键词 龙骨 理化鉴别 物相分析 元素 模式识别 质量评价
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基于《中国百年百名中医临床家丛书》探讨名家治疗不寐病的证型、证素与处方用药规律
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作者 苏啟后 彭俊杰 +1 位作者 李中 张维维 《中西医结合心脑血管病杂志》 2026年第1期27-34,共8页
目的:通过数据挖掘,探寻名家治疗不寐病的证型、证素与处方用药规律。方法:统计《中国百年百名中医临床家丛书》中所有医家治疗不寐病的医案处方,运用数据挖掘软件进行证型、证素及用药规律分析。结果:最终纳入32位现代中医名家治疗不... 目的:通过数据挖掘,探寻名家治疗不寐病的证型、证素与处方用药规律。方法:统计《中国百年百名中医临床家丛书》中所有医家治疗不寐病的医案处方,运用数据挖掘软件进行证型、证素及用药规律分析。结果:最终纳入32位现代中医名家治疗不寐病的处方共114首,药物共计197味药,总使用频次1 381次,提取出证型35种,病位证素8项和病性证素14项,统计其高频药物共有37味(频次≥10次),共计使用887次,占所有药物使用频次的64.23%。将高频次药物由高到低排序,分别统计出了其常用三种剂量及药物剂量的使用范围。证型以心肾不交证型最为常见,病位证素以心为主,病性证素以热/火为主。药物类别主要为安神药;药性以平性为重;药味尤重甘味;归经则以心经占比最高。关联规则分析发现关联强度较高的组合有16个,因子分析提取公因子14个,系统聚类分析得出5个聚类,决策树分析筛选出甘草、蒺藜和石决明3味主要中药,复杂网络分析提示核心药物为龙骨、牡蛎、酸枣仁、甘草、半夏、陈皮、茯苓等,且药物间的配伍关联性较强。结论:数据挖掘全面探讨了治疗不寐病的证型、证素与处方用药规律,对临床具有重要的指导意义。 展开更多
关键词 不寐病 《中国百年百名中医临床家丛书》 证型证素 处方用药规律 数据挖掘
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基于临床文献分析冠状动脉粥样硬化性心脏病中医证型及证素分布规律
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作者 武传玲 张军伟 +3 位作者 艾鼎 吴恬 杨蒙蒙 董秋菊 《山西中医药大学学报》 2026年第1期1-7,共7页
目的:通过临床文献检索,分析近10年来冠状动脉粥样硬化性心脏病(简称“冠心病”)的中医证型及证素分布规律。方法:制定文献纳入标准,检索自2014—2024年中国知网期刊全文数据库、万方数据知识服务平台、维普中文科技期刊数据库、中华医... 目的:通过临床文献检索,分析近10年来冠状动脉粥样硬化性心脏病(简称“冠心病”)的中医证型及证素分布规律。方法:制定文献纳入标准,检索自2014—2024年中国知网期刊全文数据库、万方数据知识服务平台、维普中文科技期刊数据库、中华医学期刊网中关于冠心病中医证型及证素的临床文献,建立冠心病中医证型及证素文献数据库,通过Excel进行频次及频率统计,并对不同年份区间中医证型及证素分布规律进行分析。结果:共总结归纳出114种证型,25类证素。对纳入文献按年份区间进行分类,频率>5%的中医证型有心血瘀阻型、气阴两虚型、痰浊内阻型、气虚血瘀型、气滞血瘀型、寒凝心脉型、心肾阴虚型、痰阻心脉型、痰瘀互结型;病性证素包括血瘀、气虚、痰、阴虚、阳虚、气滞、寒;病位证素包括心、经络、肾。共得到4种证素组合形式:(1)二证素(69.64%),其中,二病性证素(37.73%)和一病性证素+一病位证素(31.33%)占据主要地位,气虚+阴虚(11.64%)和心+血瘀(11.35%)最常见;气虚+血瘀(8.92%)和气滞+血瘀(8.15%)次之。(2)单证素,单病性证素频率为15.42%,单病位证素仅占0.19%。(3)三证素,主要集中在一病性证素+二病位证素(10.86%),其中,心+肾+阴虚出现频率最高(5.43%)。(4)四证素组合仅见四病性证素(0.10%)和二病性证素+二病位证素(0.39%)。结论:从文献视角进行二次分析,进一步明确冠心病病机特点为本虚标实、虚实夹杂的复杂态势,通过研究发现近年来虚证在冠心病病机中占主导地位,其中气阴两虚占比最大,为临床提供更为精准的诊疗策略,从而对冠心病中医病机的理解更为深入细致,为冠心病临床辨证论治提供了理论依据,进一步充实了冠心病个体化治疗的基础。 展开更多
关键词 冠状动脉粥样硬化性心脏病 中医证型 证素 频次 频率 临床文献
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鲁绣纹样解析及其数字化传承保护与创新发展策略
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作者 孙程文 《西部皮革》 2026年第1期9-11,共3页
鲁绣承载着齐鲁文化两千余年的历史与工艺智慧,其纹样体系融合自然物象、民俗信仰与儒家伦理,形成独特的视觉语言与文化内涵。文章系统解析鲁绣纹样类别与工艺特征,重点探讨数字化传承与创新路径,提出构建三维纹样库、开发沉浸式体验、... 鲁绣承载着齐鲁文化两千余年的历史与工艺智慧,其纹样体系融合自然物象、民俗信仰与儒家伦理,形成独特的视觉语言与文化内涵。文章系统解析鲁绣纹样类别与工艺特征,重点探讨数字化传承与创新路径,提出构建三维纹样库、开发沉浸式体验、引入智能设计与生产协同等策略,并借助新媒体传播构建“技术—文化—产业”生态体系,以推动鲁绣从地域性非遗向可持续、可共享的文化资源转化,为传统工艺活态传承提供实践参照。 展开更多
关键词 鲁绣 纹样元素 数字化传承 非遗保护 创新策略
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彝族服饰元素在服装设计中的应用
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作者 曹小玲 程昶月 徐佳玥 《纺织科技进展》 2026年第1期57-60,共4页
为实现彝族服饰独特款式、丰富纹样以及鲜明少数民族服饰风格在现代服装设计中的创新性融合与广泛应用,深入探讨其应用可能性,从款式、纹样和风格3个维度展开研究。结合国内外案例,分析彝族服饰元素在现代设计中的创新应用,并针对性地... 为实现彝族服饰独特款式、丰富纹样以及鲜明少数民族服饰风格在现代服装设计中的创新性融合与广泛应用,深入探讨其应用可能性,从款式、纹样和风格3个维度展开研究。结合国内外案例,分析彝族服饰元素在现代设计中的创新应用,并针对性地提出具体且具实践性的设计思路。在尊重与深入理解彝族文化的基础上,通过简化图案、合理搭配色彩,以现代化形式呈现传统文化元素,促进民族文化的传承与创新。采用现代设计技术与传统手工艺相结合的方式,详细阐述彝族服饰元素如何焕发现代时尚新生,并策略性融合民族元素与市场导向,创造出既有市场竞争力又符合消费者需求的设计作品。 展开更多
关键词 彝族服饰元素 服装设计 款式 纹样 风格
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伏牛山牛至不同生育时期对主要营养元素吸收特点及分配规律
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作者 范长有 刘林甫 +2 位作者 刘瑞 张秋月 阴志刚 《安徽农业科学》 2026年第1期175-178,190,共5页
[目的]探究牛至不同生育期生物学产量积累规律及对氮、磷、钾元素吸收积累情况。[方法]在伏牛山牛至不同生长发育阶段进行动态采样,测定伏牛山牛至植株各部位和全株的生物学产量以及氮、磷、钾含量。[结果]随着生育期的递进,牛至对氮、... [目的]探究牛至不同生育期生物学产量积累规律及对氮、磷、钾元素吸收积累情况。[方法]在伏牛山牛至不同生长发育阶段进行动态采样,测定伏牛山牛至植株各部位和全株的生物学产量以及氮、磷、钾含量。[结果]随着生育期的递进,牛至对氮、磷、钾各元素积累量与植株生物学产量呈正相关的增加趋势。4月中旬至5月下旬植株生物学产量积累量最大,达到72.80%,其中茎叶积累量达到89.54%,氮、磷、钾各元素积累量均为整个生长发育期最大值,此期氮、磷、钾各营养元素主要集中于伏牛山牛至茎叶中。[结论]伏牛山牛至植株生物学产量最大积累期为拔节期至盛花期,此期也是氮、磷、钾等营养元素积累最大时期。 展开更多
关键词 牛至 生育期 主要营养元素 吸收特点 分配规律 生物学产量
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Distribution Characteristics of Sulfur and the Main Harmful Trace Elements in China's Coal 被引量:5
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作者 TANG Shuheng SUN Shenglin +2 位作者 QIN Yong JIANG Yaofa WANG Wenfeng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2008年第3期722-730,共9页
To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for c... To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for content, and analyzed. Coal in northwestern China is characterized by low to extremely low levels of sulfur; the coal of the Taiyuan Formation in northern China mainly has high-sulfur content; that of the Shanxi Formation is mainly characterized by low sulfur coal; and the Late Permian coal in southern China has overall higher sulfur content; other regions have low sulfur coal. The average content of harmful trace elements in the bulk of China's coal is similar to the corresponding content in the coal of the North America and the rest of the world, whereas the content of various elements (Hg, Sb and Se) is different in magnitude to the corresponding percentage in the crust. The average content of the elements Cr, Se, Co, Be, U, Br in Late Permian coal in S China ranks first in the country whereas the average content of Hg and CI in the coals of Late Carboniferous to Early Permian age in N China are the highest. The average content of Mn in Early and Middle Jurassic coal is higher in NW China. The high content of harmful elements in some coal should cause particular concern both in the development and utilization of coal. 展开更多
关键词 COAL SULFUR harmful trace elements distribution patterns ENVIRONMENT China
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Characteristics and environmental significance of rare earth elements in PM2.5 of Nanchang, China 被引量:9
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作者 ZHAO Yang YU Ruilian +2 位作者 HU Gongren LIN Xiaohui LIU Xianrong 《Journal of Rare Earths》 SCIE EI CAS CSCD 2017年第1期98-106,共9页
Concentrations of sixteen rare earth elements(REEs) in PM2.5 and potential-source samples, collected in Nanchang city in mid-September 2013, were determined by inductively coupled plasma mass spectrometry(ICP-MS).... Concentrations of sixteen rare earth elements(REEs) in PM2.5 and potential-source samples, collected in Nanchang city in mid-September 2013, were determined by inductively coupled plasma mass spectrometry(ICP-MS). The results showed that the concentrations of total REEs(ΣREE) ranged from 78.76 to 1351 ng/mg. The order of REEs in PM2.5 samples showed the anthropogenic effects, Ce and Eu were affected more than the other REEs according to the enrichment factors. The results of chondrite-normalized REEs patterns and characteristic parameters showed evident light REEs fractionation, and positive anomalies of Ce and Eu in PM2.5. The other non-local pollution sources affected the PM2.5 samples, according to the triangular diagram of La, Ce and Sm compositions and plot of ΣREE vs δEu. Moreover, plot of(La/Sm)N vs(Gd/Yb)N revealed the effects of local sources. In conclusion, the REEs in potential-source samples were close to the background of local soil, while the REEs in PM2.5 samples in Nanchang city were jointly affected by the investigated local sources and other non-local sources. 展开更多
关键词 PM2.5 rare earth elements composition characteristics distribution pattern enrichment factor
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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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INVESTIGATION ON TRACE ELEMENTS IN CRUDE OILS AND ORGANIC MATERIALS EXTRACTED FROM OIL-FORMING SOURCE ROCKS IN CHINA WITH INAA
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作者 柴之芳 丁祖国 +1 位作者 傅家谟 盛国英 《Nuclear Science and Techniques》 SCIE CAS CSCD 1991年第2期85-90,共6页
A combination of Soxhlet extraction, column chromatography and INAA with GC and GC- MS was used in this work for the study of the abundance patterns of 36 trace elements and their correlation in nearly 100 samples of ... A combination of Soxhlet extraction, column chromatography and INAA with GC and GC- MS was used in this work for the study of the abundance patterns of 36 trace elements and their correlation in nearly 100 samples of crude oil and organic materials extracted from oil- forming source rocks from 10 main Chinese oilfields. The low V/Ni ratios of 0.01 to 0.3 state the oil- forming continent environment. The geochemical significance hinted from other trace element abundances is also briefly discussed. 展开更多
关键词 Neutron activation analysis CRUDE oil TRACE element pattern
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SIMULATION OF ELECTRICAL FIELD FOR THE FORMATION MECHANISM OF BIRD'S NEST PATTERNED STRUCTURES BY ELECTROSPINNING 被引量:2
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作者 Xiang-yu Ye Yi-ning Jin +2 位作者 Xiao-jun Huang Lei Luo 徐志康 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2013年第3期514-520,共7页
In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird's Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechan... In our previous work, it was found that large electrospun from chlorinated polypropylene solution doped Bird's Nest patterned nanofibrous membranes can be simply with an ionic liquid, and a plausible formation mechanism of Bird's Nest patterned architectures was proposed. Here, we use Ansoft Maxwell version 12 software (3D, electrostatic solver) to simulate the electrical field distribution of the electrospinning setup, and to clarify the rationality of proposed formation mechanism. Calculation results clearly show that the introduction of charged nanofibrous bundles would produce a similar patterned electrical field distribution, which definitely confirms the important role of surface residual charges. The proposed mechanism can be well extended to other polymer systems including polystyrene, poly(acrylonitrile-co-acrylic acid) and chitosan/poly(ethylene oxide). 展开更多
关键词 ELECTROSPINNING patterned structures Finite element analysis Electrical field Theoretical simulation.
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Petrogenetic significance of rare-earth element behavior in the basement rocks of southern Obudu Plateau, Bamenda Massif, southeastern Nigeria
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作者 UKAEGBU V.U. EKWUEME B.N. 《Chinese Journal Of Geochemistry》 EI CAS 2005年第2期129-135,共7页
Rock samples representing various igneous and metamorphic rocks of southern Obudu Plateau were analyzed for rare-earth element (REE) behavior by ICP-MS. Results of the analyses indicate a range of REE abundances and d... Rock samples representing various igneous and metamorphic rocks of southern Obudu Plateau were analyzed for rare-earth element (REE) behavior by ICP-MS. Results of the analyses indicate a range of REE abundances and distinctive patterns from highly fractionated patterns with negative Eu anomalies in granitic rocks to relatively low abundances and less REE fractionated flat patterns with little Eu anomaly in some paragneisses, schists, enderbites and dolerites to unfractionated patterns with positive Eu anomalies in some paragneisses and charnockites. Over all, there are low to high ∑REE contents with negative to positive Eu anomalies. The ratios of different parameters, especially La/Yb and Ce/Yb, show behaviors consistent with crustal to mantle derivation. The heterogeneity of REE abundances and REE patterns reflects mantle to crustal petrogenetic variations of different rock suites on the Plateau. The LREE content is higher than the HREE content in the highly differentiated rocks, as evidenced by their La/Yb, Ce/Yb and La/Sm ratios, which are normally higher in residual products than in primary melts. The dominantly intermediate nature of the source rock of the orthogneisses is suggested by the generally low {∑REE}. The granites enriched in LREE and depleted in HREE and some of the charnockites with negative Eu anomalies were probably formed by partial melting and crystallization. 展开更多
关键词 稀土元素 地球化学 丰度 Obudu高原 变质岩
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Grating Lobe Suppression with Element Count Optimization in Planar Antenna Array
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作者 B. Rama Sanjeeva Reddy D. Vakula 《Journal of Electromagnetic Analysis and Applications》 2015年第2期31-40,共10页
The novel approach of this paper describes the suppression of grating lobe level with the element count optimization in planar antenna array. Rectangular lattice (RL) and triangular lattice (TL) structures are chosen ... The novel approach of this paper describes the suppression of grating lobe level with the element count optimization in planar antenna array. Rectangular lattice (RL) and triangular lattice (TL) structures are chosen for determining the achievable array element patterns (EP) and further suppressing the grating lobe level. The element spacing and number of elements (10 × 20 array) are taken into account for particular lattice. Grating lobe peaks are observed for the 200-element planar array at maximum scan angle (θ) with the set frequency of 3 GHz. Further, it is found that 14°;bore sight elevation of rectangular lattice produces a transformed field of view, which permits a reduction in element count of 20.39% compared with 10° bore sight elevation. Finally, the typical values of elevation, element count and array size (25 cm2) are trained using artificial neural network (ANN) algorithm and element count is predicted after testing the network. The network shows a high success rate. 展开更多
关键词 Rectangular LATTICE (RL) TRIANGULAR LATTICE (TL) element pattern (EP) Artificial Neural Network (ANN)
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Study of elemental distribution in soil on the loess plateau of China
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作者 Tian Junliang, Li Yaqi Liu PulingNorthwestern Institute of Soil and Water Conservation, Chinese Academy of Sciences, Shaanxi 712100, China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1993年第1期37-44,共8页
Instrument neutron activation analysis (INAA) has been employed in this study to determine 32 elements in soil on the loess plateau. The preliminary results suggest that geochemical characteristics of elements in the ... Instrument neutron activation analysis (INAA) has been employed in this study to determine 32 elements in soil on the loess plateau. The preliminary results suggest that geochemical characteristics of elements in the soil mainly retained those in the parent materials (loess). It has been found that fractional deposition among grain sizes in the process of loess transportation as well as the bioclimate in which the soil developed are main factors affecting the regional variations of elemental distribution in soil on the plateau. Contour maps of element concentrations plotted from the trend analyses exhibit the major patterns of the distributions and variations on the plateau. Furthermore, the study also provides evidence for the aeolian theory of the loess transportation in China. 展开更多
关键词 elements SOIL loess plateau variation patterns.
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苏南地区臭氧污染的气象条件分析 被引量:1
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作者 黄文彦 雷正翠 +2 位作者 何涛 姚丽娜 吴建秋 《气象与环境科学》 2025年第6期53-63,共11页
利用20192021年苏南五市国控点臭氧资料和同期国家气象站观测数据及ERA5再分析资料,分析苏南地区臭氧污染时空分布特征及其与相关气象要素之间的关系,并对造成臭氧污染的天气形势进行分类。结果表明:苏南五市不同城市之间臭氧浓度日变... 利用20192021年苏南五市国控点臭氧资料和同期国家气象站观测数据及ERA5再分析资料,分析苏南地区臭氧污染时空分布特征及其与相关气象要素之间的关系,并对造成臭氧污染的天气形势进行分类。结果表明:苏南五市不同城市之间臭氧浓度日变化差异主要出现在白天,全年臭氧浓度分布有两个峰值。当气温在30~35℃、日照时数大于10 h、相对湿度在30%~60%、风速达1~3 m/s和风向盛行偏南风时,苏南五市臭氧超标污染率达最大值。苏州臭氧超标污染率显著小于其他四市的。苏南(除苏州外)臭氧全域超标污染时,苏州地区后向轨迹中有60%的轨迹主要通过东部海洋;苏州较高的总云量和较低的总辐射不利于光化学反应生成臭氧。苏南地区臭氧污染的天气类型主要有槽后西北气流型(69%)、短波槽型(17%)和副高控制型(14%)。槽后西北气流控制下,南京和苏州后向轨迹中主要传输路径分别为源于安徽沿江一带往东北方向输送和源于杭州湾附近往西北方向输送。 展开更多
关键词 苏南 臭氧污染 气象要素 天气型 后向轨迹
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