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INDA Announces Nominees for IDEA13 Achievement Awards
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《China Textile》 2013年第2期14-14,共1页
Industry members will vote on three finalists per category and the winners will be announced at IDEA13 in Miami Beach in AprilA total of 15 of the most innovative and successful new products in the nonwovens and engin... Industry members will vote on three finalists per category and the winners will be announced at IDEA13 in Miami Beach in AprilA total of 15 of the most innovative and successful new products in the nonwovens and engineered fabrics industries over the past three years have been nominated as finalists for the prestigious IDEA13 Achievement Awards. 展开更多
关键词 代理人 da 迈阿密 获奖者
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A Self-Adapting and Efficient Dandelion Algorithm and Its Application to Feature Selection for Credit Card Fraud Detection
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作者 Honghao Zhu MengChu Zhou +1 位作者 Yu Xie Aiiad Albeshri 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期377-390,共14页
A dandelion algorithm(DA) is a recently developed intelligent optimization algorithm for function optimization problems. Many of its parameters need to be set by experience in DA,which might not be appropriate for all... A dandelion algorithm(DA) is a recently developed intelligent optimization algorithm for function optimization problems. Many of its parameters need to be set by experience in DA,which might not be appropriate for all optimization problems. A self-adapting and efficient dandelion algorithm is proposed in this work to lower the number of DA's parameters and simplify DA's structure. Only the normal sowing operator is retained;while the other operators are discarded. An adaptive seeding radius strategy is designed for the core dandelion. The results show that the proposed algorithm achieves better performance on the standard test functions with less time consumption than its competitive peers. In addition, the proposed algorithm is applied to feature selection for credit card fraud detection(CCFD), and the results indicate that it can obtain higher classification and detection performance than the-state-of-the-art methods. 展开更多
关键词 Credit card fraud detection(CCFD) dandelion algorithm(da) feature selection normal sowing operator
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DA-Transformer:基于“门”注意力的文本情感分析方法
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作者 李苗 关力 张扬 《西安文理学院学报(自然科学版)》 2023年第4期35-39,共5页
为了解决Transformer对中文文本词语建模时容易造成信息冗余这一问题,提出了一种“门”注意力结合Transformer(DA-Transformer)的情感分析模型.该模型通过在Transformer模型中的编码和解码过程中插入一种基于自注意力的“门”注意力(DA... 为了解决Transformer对中文文本词语建模时容易造成信息冗余这一问题,提出了一种“门”注意力结合Transformer(DA-Transformer)的情感分析模型.该模型通过在Transformer模型中的编码和解码过程中插入一种基于自注意力的“门”注意力(DA)来建立文本的长远距离依赖,加速模型学习深层特征与浅层特征的权重比值.本模型在ChnSentiCorp_htl_al和weibo_senti数据集上得到验证.实验表明,本模型的准确率比BLSTM的准确率高1.8%,比BLSTM-Attention模型的准确率高0.9%,表明本模型具有一定的优异性与可实行性. 展开更多
关键词 文本情感分析 Transformer模型 信息冗余 自注意力机制 da
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Translator Stylistics:A Corpus Analysis of Two English Translations of Traditional Chinese Medicine Classic Da Sheng Bian
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作者 Yang Zhang Yue’e Zhu 《Journal of Contemporary Educational Research》 2023年第12期367-375,共9页
Da Sheng Bian,a significant work on obstetrics and gynecology that emerged in the early Qing Dynasty,was initially published as“A Treatise on Midwifery”in 1842 by William Lockhart,a British missionary to China.In 18... Da Sheng Bian,a significant work on obstetrics and gynecology that emerged in the early Qing Dynasty,was initially published as“A Treatise on Midwifery”in 1842 by William Lockhart,a British missionary to China.In 1894,John G.Kerr,an American missionary,translated the text as“The Tat Shang Pin”.This paper conducts a comparative study of the two English translations using a self-constructed English-Chinese parallel corpus of Da Sheng Bian.The study explores the translation styles of the two translators by examining the token-types ratio and frequency at the lexical level,mean sentence length at the syntactic level,and the use of conjunctions at the discourse level.The observed differences in translation styles between the two translations are analyzed in relation to the translators’backgrounds and translation strategies. 展开更多
关键词 CORPUS da sheng bian Translator style
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基于DA多重插补法和电力物联网的电能数据缺失修复方法
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作者 张浩海 王昊 丁耀杰 《电子设计工程》 2024年第8期101-105,110,共6页
针对电力物联网中电能数据量过多,缺失电能数据修复难度较大的问题,研究基于DA多重插补法和电力物联网的电能数据缺失修复方法。电力物联网利用感知层的电能数据采集终端采集电能数据,所采集电能数据利用通信层传送至应用层,应用层的电... 针对电力物联网中电能数据量过多,缺失电能数据修复难度较大的问题,研究基于DA多重插补法和电力物联网的电能数据缺失修复方法。电力物联网利用感知层的电能数据采集终端采集电能数据,所采集电能数据利用通信层传送至应用层,应用层的电能数据缺失修复模块,利用EM插补算法计算电能数据缺失值的初始插补值;将所获取的电能数据插补值作为DA多重插补法的初始值,DA多重插补法利用局部加权回归模型,通过调整电能数据缺失值的预测误差,获取最终电能数据缺失修复结果。实验结果表明,该方法修复电力物联网电能数据的观测误差方差低于0.2,对于短期电能数据与长期电能数据,均具有良好的修复结果。 展开更多
关键词 da多重插补法 电力物联网 电能数据 缺失修复 EM插补算法 局部加权回归
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胎圈钢丝用钢盘条C82DA的CCT曲线测定及应用
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作者 胡楠 韩书栋 +2 位作者 张伟 许荣 王钦仁 《山西冶金》 CAS 2024年第3期56-59,共4页
为了研究分析高性能胎圈钢丝用钢盘条C82DA在不同冷却速度下组织转变,达到产品工艺精细化控制的目的,利用Gleeble-3500热模拟试验机和光学显微镜对不同冷却速率的试样进行显微组织分析,绘制连续冷却转变曲线。分析结果显示:开始产生马... 为了研究分析高性能胎圈钢丝用钢盘条C82DA在不同冷却速度下组织转变,达到产品工艺精细化控制的目的,利用Gleeble-3500热模拟试验机和光学显微镜对不同冷却速率的试样进行显微组织分析,绘制连续冷却转变曲线。分析结果显示:开始产生马氏体组织的临界冷速为20℃/s,冷却速度在0.5~10℃/s时组织为珠光体和索氏体,但组织中有明显网状渗碳体;冷却速度在12~20℃/s时组织为珠光体和索氏体;通过对比发现,冷却速率为10~15℃/s时,胎圈钢丝用钢盘条C82DA的综合性能达到最佳。 展开更多
关键词 C82da盘条 CCT曲线 胎圈钢丝 索氏体
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Ricon154DA对变压器设备密封用HNBR胶料的性能影响
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作者 冀建波 冯婧 +4 位作者 安静 盛国辉 孙波 娄楼 岳炯 《橡胶参考资料》 2024年第3期23-25,37,共4页
研究了Ricon154DA对过氧化二异丙苯(DCP)硫化的氢化丁腈橡胶(HNBR)胶料的性能影响。研究发现,当DCP用量为3份、Ricon154DA用量为1.5份时,可以获得性能优异的HNBR胶料,其硫化胶具有优良的物理机械性能、耐高温老化性能、抗压缩永久变形... 研究了Ricon154DA对过氧化二异丙苯(DCP)硫化的氢化丁腈橡胶(HNBR)胶料的性能影响。研究发现,当DCP用量为3份、Ricon154DA用量为1.5份时,可以获得性能优异的HNBR胶料,其硫化胶具有优良的物理机械性能、耐高温老化性能、抗压缩永久变形性能、耐变压器油性能、耐臭氧老化性能和耐低温性能,满足变压器设备密封的使用要求。 展开更多
关键词 HNBR Ricon154da 交联密度 耐油性
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DA42NG飞机涡轮增压系统典型故障分析
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作者 那超 《现代制造技术与装备》 2024年第6期48-50,共3页
涡轮增压系统对于飞机的飞行性能和经济性都有着至关重要的影响,它能够提高发动机效率、减少燃油消耗和排放、提升飞行的操作灵活性和安全可靠性。对于装配有涡轮增压系统的飞机而言,涡轮增压系统故障是发生率和维护成本较高的故障之一... 涡轮增压系统对于飞机的飞行性能和经济性都有着至关重要的影响,它能够提高发动机效率、减少燃油消耗和排放、提升飞行的操作灵活性和安全可靠性。对于装配有涡轮增压系统的飞机而言,涡轮增压系统故障是发生率和维护成本较高的故障之一。文章以DA42NG飞机的涡轮增压系统为研究对象,首先分析系统的组成和工作原理,其次剖析典型故障的原因,最后提出维护建议,以期为该机型及类似机型相关故障的排除提供参考。 展开更多
关键词 da42NG飞机 涡轮增压系统 典型故障 维护
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大行(DAHON)2024年度全国代理商大会盛大开幕
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《中国自行车》 2024年第3期4-4,共1页
2024年3月20日,大行(DAHON)2024年度全国代理商大会于海南三亚圆满结束。大会回顾总结了大行2023年度取得的傲人成绩,对2024年度技术新品、营销策略、渠道政策、战略目标等内容进行宣讲,表彰了上年度优秀代理商,还发起了愉悦畅快的试骑... 2024年3月20日,大行(DAHON)2024年度全国代理商大会于海南三亚圆满结束。大会回顾总结了大行2023年度取得的傲人成绩,对2024年度技术新品、营销策略、渠道政策、战略目标等内容进行宣讲,表彰了上年度优秀代理商,还发起了愉悦畅快的试骑活动。 展开更多
关键词 全国代理商 渠道政策 营销策略 海南三亚 战略目标 优秀代理商 da HO
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基于FMEA分析法的DA42NG飞机燃油系统典型故障分析
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作者 王汉龙 《中文科技期刊数据库(全文版)工程技术》 2024年第8期0148-0152,共5页
本文采用故障模式和影响分析(FMEA)方法,对DA42NG飞机的燃油系统进行了全面的故障分析。首先,我们对燃油系统的组成和工作原理进行了概述,然后介绍了FMEA分析法,详细识别了可能出现的故障模式,并评估它们对飞机操作的影响,确定了高风险... 本文采用故障模式和影响分析(FMEA)方法,对DA42NG飞机的燃油系统进行了全面的故障分析。首先,我们对燃油系统的组成和工作原理进行了概述,然后介绍了FMEA分析法,详细识别了可能出现的故障模式,并评估它们对飞机操作的影响,确定了高风险的故障模式,并针对这些模式制定了相应的改进措施,以确保飞机燃油系统的可靠性和安全性。 展开更多
关键词 da42NG飞机 燃油系统 FMEA分析法
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富电子1,3-二烯的DA与HDA反应研究进展
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作者 滕家兵 张远飞 《南宁师范大学学报(自然科学版)》 2024年第1期96-109,共14页
DA(Diels-Alder)与HDA(Hetero Diels-Alder)反应是构建含多个手性碳的六元环的最有效方法,广泛应用于复杂天然产物的全合成中。在这两类反应的研究中,在富电子1,3-二烯的结构中引入氧、氮等杂原子,以其能降低DA与HAD反应的活化能与能有... DA(Diels-Alder)与HDA(Hetero Diels-Alder)反应是构建含多个手性碳的六元环的最有效方法,广泛应用于复杂天然产物的全合成中。在这两类反应的研究中,在富电子1,3-二烯的结构中引入氧、氮等杂原子,以其能降低DA与HAD反应的活化能与能有效地进行后续多样性转化等特点,受到了有机合成化学界的广泛关注。富电子1,3-二烯的合成及其DA与HAD反应的研究已经取得了一些成果,在天然产物的合成中展现出很大优势,具有广阔的发展与应用前景。该文综述了富电子1,3-二烯,包括Danishefsky二烯、Brassard二烯、Rawal二烯等的合成及其DA与HDA反应的研究进展。 展开更多
关键词 富电子二烯 da反应 Hda反应 六元(杂)环
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ASIC Design of DA-Based 2-D Inverse Discrete Cosine Transform
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作者 陈禾 韩月秋 《Journal of Beijing Institute of Technology》 EI CAS 1999年第2期56-63,共8页
目的给出基于DA算法的二维离散余弦逆变换(2DIDCT)的ASIC设计.方法设计中一维IDCT算法采用基于Chen的快速1DIDCT算法.为了减少面积、加快速度,设计中乘法累加电路是采用基于DA算法而实现的.结果... 目的给出基于DA算法的二维离散余弦逆变换(2DIDCT)的ASIC设计.方法设计中一维IDCT算法采用基于Chen的快速1DIDCT算法.为了减少面积、加快速度,设计中乘法累加电路是采用基于DA算法而实现的.结果与结论完成了整个系统的VHDL仿真、综合及版图设计.与目前国际上较优秀的设计相比,本设计拥有最好的时序特性,设计总体结果较优. 展开更多
关键词 离散余弦变换 da算法 VHSIC硬件描述语言
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DAE、DA方案治疗初治ANLL 61例 被引量:2
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作者 刘德斌 陈瑜 +5 位作者 周励 姚富生 曾晓颖 孙慧平 李秀松 沈志祥 《临床血液学杂志》 CAS 1998年第2期85-86,共2页
对本科住院治疗的初治急性作淋巴细胞白血病(ANLL)61例,分别给于DA、DAE方案化疗。结果:①初治ANLLDA方案的CR率64.3%,DAE方案CR率75.8%,两者CR率P>0.05;②达CR时所需的疗程:DA方案1.7疗程,DAE方案1.4疗程;③两方案... 对本科住院治疗的初治急性作淋巴细胞白血病(ANLL)61例,分别给于DA、DAE方案化疗。结果:①初治ANLLDA方案的CR率64.3%,DAE方案CR率75.8%,两者CR率P>0.05;②达CR时所需的疗程:DA方案1.7疗程,DAE方案1.4疗程;③两方案毒副反应大致相似、可以耐受。结论:DAE方案并不能提高CR率,但可能加快CR过程,且不增加毒副作用,可推广运用。 展开更多
关键词 da方案 daE方案 白血病 急性 治疗
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GLP-1/GIP双靶点受体激动剂DA5-CH对脑缺血再灌注损伤大鼠脑组织的作用及其机制研究
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作者 董丽荣 徐娜 吕建东 《中国现代医学杂志》 CAS 北大核心 2023年第6期25-29,共5页
目的研究胰高血糖素样肽-1/抑胃肽(GLP-1/GIP)双靶点受体激动剂DA5-CH对脑缺血再灌注损伤(I/R)大鼠脑组织的作用及其可能机制。方法将30只脑I/R大鼠随机分为模型组、DA5-CH组、DA5-CH+SB431542组,每组10只。另取10只大鼠仅做假手术(假... 目的研究胰高血糖素样肽-1/抑胃肽(GLP-1/GIP)双靶点受体激动剂DA5-CH对脑缺血再灌注损伤(I/R)大鼠脑组织的作用及其可能机制。方法将30只脑I/R大鼠随机分为模型组、DA5-CH组、DA5-CH+SB431542组,每组10只。另取10只大鼠仅做假手术(假手术组)。DA5-CH组腹腔注射10 nmol/kg DA5-CH;DA5-CH+SB431542组腹腔注射10 nmol/kg DA5-CH和5 mg/kg SB431542,假手术组、模型组腹腔注射等体积生理盐水。检测各组大鼠脑组织含水量;免疫组织化学染色检测海马CA1区神经核抗原(NeuN)阳性细胞数;Western blotting检测脑组织转化生长因子β1(TGF-β1)、Smad3、p-Smad3蛋白的表达。结果与假手术组比较,模型组脑组织含水量增加,海马CA1区每个视野NeuN阳性细胞数减少,脑组织TGF-β1、p-Smad3/Smad3蛋白表达升高(P<0.05);与模型组比较,DA5-CH组脑组织含水量降低,海马CA1区NeuN阳性细胞数增加,脑组织TGF-β1、p-Smad3/Smad3蛋白表达降低(P<0.05);与DA5-CH组比较,DA5-CH+SB431542组脑组织含水量增加,海马CA1区NeuN阳性细胞数减少,脑组织TGF-β1、p-Smad3/Smad3蛋白表达升高(P<0.05)。结论GLP-1/GIP双靶点受体激动剂DA5-CH可保护脑I/R大鼠神经功能,减少脑组织含水量及神经元坏死,减轻海马区病理改变,其作用机制可能与激活TGF-β1/Smads通路有关。 展开更多
关键词 脑缺血再灌注 胰高血糖素样肽-1/抑胃肽双靶点受体激动剂 da5-CH 神经功能 大鼠
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基于SIMCA、PLS-DA、WT-ANN模型的椰子油掺混定性识别研究 被引量:1
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作者 曹飞宇 王兴国 +1 位作者 陈卫军 王挥 《中国粮油学报》 EI CAS CSCD 北大核心 2016年第1期137-141,共5页
根据不同油脂的紫外特征光谱,利用SIMCA,PLS-DA,WT-ANN 3种模型对椰子油中掺混大豆油、葵花籽油和玉米油的油脂类别进行判定分析。结果显示,WT-ANN对3种掺混油脂类别的识别效果最佳,预测集R^2分别达到了0.9989(大豆油)、0.9811(葵花籽油... 根据不同油脂的紫外特征光谱,利用SIMCA,PLS-DA,WT-ANN 3种模型对椰子油中掺混大豆油、葵花籽油和玉米油的油脂类别进行判定分析。结果显示,WT-ANN对3种掺混油脂类别的识别效果最佳,预测集R^2分别达到了0.9989(大豆油)、0.9811(葵花籽油)、0.9999(玉米油),且在不同浓度下识别率均达到了100%,而SIMCA和PLS-DA的识别准确度相对较低,且受掺混浓度的影响较大。WT-ANN结合紫外光谱是一种有效判定椰子油中掺混油脂类别的分析方法。 展开更多
关键词 椰子油 定性识别 SIMCA PLS—da WT—anN
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Mesozoic Bimodal Volcanic Suite in Zhalantun of the Da Hinggan Range and Its Geological Significance: Zircon U-Pb Age and Hf Isotopic Constraints 被引量:52
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作者 ZHANG Jiheng GE Wenchun +1 位作者 WU Fuyuan LIU Xiaoming 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期58-69,共12页
Mesozoic bimodal volcanic rocks of basaltic andesite and rhyolite are widely distributed in the Da Hinggan Range, but their petrogenetic relationships and geodynamic implications are rarely constrained. Detailed studi... Mesozoic bimodal volcanic rocks of basaltic andesite and rhyolite are widely distributed in the Da Hinggan Range, but their petrogenetic relationships and geodynamic implications are rarely constrained. Detailed studies on doleritic and porphyry dikes in the Zhalantun area indicate that they display features of magma mixing, suggesting their coeval formation. In situ zircon U-Pb dating shows that the porphyry was emplaced in the Early Cretaceous with a ^206Pb/^238U age of 130±1 Ma. Zircons from the dolerite also yield an Early Cretaceous emplacement age of 124±2 Ma although some inherited zircons have been identified. These age results indicate that the Early Cretaceous was an important period of magmatism in the Da Hinggan Range. Zircons from porphyry are characterized by positive value of εHf(t) as high as 10.3±0.5 with Hf depleted mantle model age of 349-568 Ma, whereas magmatic zircons from the dolerite have εHf(t) value of 11.0±1.4 with Hf depleted mantel model age of 342-657 Ma, consistent with those from the porphyry. Considering other data on the geological evolution of this area, it is concluded that the mafic magma originated from the partial melting of Paleozoic enriched lithospheric mantle, whereas the felsic magma came from recycling of juvenile crust formed during the Paleozoic. Both of the protoliths are closely related to the subduction of the Paleo-Asian Ocean during the Paleozoic, indicating that the Paleozoic is an important period of large-scale crustal growth in the area. 展开更多
关键词 volcanic rocks zircon U-Pb dating Hf isotope crustal growth da Hinggan Range NE China
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Relationship between Mesozoic Magmatism and Subduction in the Da Hinggan-Yanshan Area 被引量:9
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作者 SHAO Ji'an LIU Futian +1 位作者 CHEN Hui HAN Qingjun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第1期1-8,共9页
High-resolution tomographic images of the belt crossing the Japan Trench-Changbai Mountains-Dong Ujimqin Qi are represented in this paper, revealing the shape of a subducted slab in the western Pacific region and char... High-resolution tomographic images of the belt crossing the Japan Trench-Changbai Mountains-Dong Ujimqin Qi are represented in this paper, revealing the shape of a subducted slab in the western Pacific region and characteristics of the lithospheric structures under the Changbai Mountains and the Da Hinggan Mountains. Studies of the spatial distribution, subduction time and the time-lag between the subduction and magmatism, combined with petrology and isotope geochemistry of the Late Mesozoic volcano-plutonic rocks from the Da Hinggan Mountains-Yanshan Mountains have further proved the independence of magmatic activities from the subduction of the Pacific plate. The Mesozoic tectono-thermal evolutionary history and structural characteristics of the lithosphere in the Da Hinggan Mountains and North China suggest that the formation and evolution of magma have probably a close relationship with the delamination and thinning of the continental lithosphere and the underplating resulting from the consequent upwelling of the asthenosphere. On the other hand, the large-scale strike-slip fault system, resulting from sinistral shearing of the Pacific plate relative to the Asian continent in the Mesozoic, is responsible for the formation and emplacement of magma on the continental margin. It was the intense crust-mantle interaction, together with structural deformation at the shallower levels that led to the large tectono-magmatic belt in the East Asian continental margin. 展开更多
关键词 da Hinggan-Yanshan Mountains volcanic-plutonic rock SUBDUCTION tomographic image
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Discovery and Significance of Quaternary Glacial Vestiges in the Hexigten Area of the Southern Da Hinggan Mountains, Inner Mongolia 被引量:7
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作者 SUN Hongyan TIAN Mingzhong +1 位作者 WU Fadong ZHANG Jianping 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2005年第4期564-569,共6页
The question whether there have been Quaternary glaciations in the Da Hinggan area has puzzled glacial geologists for many years because no sufficient glacial evidence has been found in this area. The study of Quatern... The question whether there have been Quaternary glaciations in the Da Hinggan area has puzzled glacial geologists for many years because no sufficient glacial evidence has been found in this area. The study of Quaternary glaciers in the Da Hinggan area is also a key issue of the glaciology in China because of the special location of this area. In the past two years, a large number of complete and typical glacial vestiges have been found in Hexigten in the southern Da Hinggan Mountains, such as fossil cirque groups, horns, knife-edge crests, terminal moraines, glacial stepped stones. These landforms are located at a watershed, which are thus impossible to be formed due to tectonic processes, water or weathering, but can only be formed by glaciation. The calculated flat indexes of the fossil cirques in the Hexigten are 1.7-4.5, 4-5 and 1.3-5, which are within the range of 1.7-5 that is the flat index of real cirques. The typical and complete moraines have also been found in this area. All these glacial vestiges prove that the Quaternary glaciers did exist in the Da Hinggan Mountains of eastern China. Thus, it is of important scientific significance for the research on Chinese, even the global climatic and environmental evolution since the Quaternary. 展开更多
关键词 da Hinggan Mountains Hexigten Quaternary glacial vestiges
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Geology and Geochemistry of the Bianbianshan Au-Ag-Cu-Pb-Zn Deposit, Southern Da Hinggan Mountains, Northeastern China 被引量:6
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作者 ZENG Qingdong LIU Jianming LIU Hongtao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2012年第3期630-639,共10页
The Bianbianshan deposit, the unique gold-polymetal (Au-Ag-Cu-Pb-Zn) veined deposit of the polymetal metallogenic belt of the southern segment of Da Hinggan Mountains mineral province, is located at the southern par... The Bianbianshan deposit, the unique gold-polymetal (Au-Ag-Cu-Pb-Zn) veined deposit of the polymetal metallogenic belt of the southern segment of Da Hinggan Mountains mineral province, is located at the southern part of the Hercynian fold belt of the south segment of Da Hinggan Mountains mineral province, NE China. Ores at the Bianbianshan deposit occur within Cretaceous andesite and rhyolite in the form of gold-bearing quartz veins and veinlet groups containing native gold, electrum, pyrite, chalcopyrite, galena and sphalerite. The deposit is hosted by structurally controlled faults associated with intense hydrothermal alteration. The typical alteration assemblage is sericite + chlorite + calcite + quartz, with an inner pyrite-sericite-quartz zone and an outer seicite - chlorite - calcite-epidote zone between orebodies and wall rocks. δ34 S values of 17 sulfides from ores changing from -1.67 to +0.49‰ with average of -0.49‰, are similar to δ34 S values of magmatic or igneous sulfide sulfur. 206Pb/204Pb, 207Pb/204Pb and 208Pb/ 204Pb data of sulfide from ores range within 17.66-17.75, 15.50-15.60, and 37.64-38.00, respectively. These sulfur and lead isotope compositions imply that ore-forming materials might mainly originate from deep sources. H and O isotope study of quartz from ore-bearing veins indicate a mixed source of deep-seated magmatic water and shallower meteoric water. The ore formations resulted from a combination of hydrothermal fluid mixing and a structural setting favoring gold-polymetal deposition. Fluid mixing was possibly the key factor resulting in Au-Ag-Cu-Pb-Zn deposition in the deposit. The metallogenesis of the Bianbianshan deposit may have a relationship with the Cretaceous volcanic-subvolcanic magmatic activity, and formed during the late stage of the crust thinning of North China. 展开更多
关键词 Gold-polymetal deposit ISOTOPES da Hinggan Mountains China
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NORTH QAIDAM ULTRAHIGH PRESSURE METAMORPHIC (UHPM) BELT ON THE NORTHEASTERN QINGHAI-TIBET PLATEAU AND ITS EASTWARD EXTENSION 被引量:3
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作者 Yang Jingsui 1, Song Suguang 1, Wu Cailai 1, Shi Rendeng 1, Marc Jalivet 2(1 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2 Department of Geology, University of Montpellier II, Montpellier, France) 《地学前缘》 EI CAS CSCD 2000年第S1期241-242,共2页
Eclogite was firstly discovered at the Da Qaidam region (Yang,et al., 1998), and then in the Xitieshan and Dulan regions in 1999, constituting an over 350km long high\|pressure metamorphic belt in the northeastern Qin... Eclogite was firstly discovered at the Da Qaidam region (Yang,et al., 1998), and then in the Xitieshan and Dulan regions in 1999, constituting an over 350km long high\|pressure metamorphic belt in the northeastern Qinghai—Tibet plateau. Eclogites occur as pods in the garnet\|muscovite gneiss of the Dakendaban Group (or called Shaliuhe Group in Dulan) of Upper Proterozoic age. In general, the pods of eclogite vary in size; most of them are less than 20m×10m, some large ones up to about 100m×50m. The eclogite\|hosted gneiss is pale\|gray in color, consisting mainly plagioclase and quartz, and minor muscovite (5%~10% in vol.) and garnet (1%~2%). Some of the country rocks of eclogite are mica\|quartz\|(feldspar) schist, quartzite, and ultramafic rocks, the latter also occur in blocks.Over 50 pods were found in a belt of 10km×3km in the Da Qaidam region (No.1 location). Only a few pods of eclogite were found in the Xitieshan region in 1999 field expedition (No.2 location). Eclogite in Dulan occurs in the Proterozoic strata of Shaliuhe Group (same as the Dakendaban Group but with a different name). The eclogites in the Dulan region (No.3 location) expose about 10km wide in SN and an unknown length in EW, and can be subdivided into two belts, the North Eclogite Belt of Dulan (NEBD) and the South Eclogite Belt of Dulan (SEBD). 展开更多
关键词 ECLOGITE UHP ultrahigh pressure METAMORPHISM COESITE dulan da Qaidam QINGHAI Tibet
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