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Span 80-P507体系萃取稀土防止乳化试验研究
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作者 张秋露 刘杰 +4 位作者 王志荣 薛志潇 李倩婷 高丽 张家起 《湿法冶金》 北大核心 2025年第3期388-397,共10页
溶剂萃取法是稀土分离提纯的主要方法之一,但在工业生产过程中常因工艺条件控制不当而发生乳化现象。为了解决这一难题,研究了以表面活性剂Span 80为调控剂、P507为萃取剂、煤油为稀释剂萃取稀土,考察了水相pH、搅拌速度和水油相比对Er^... 溶剂萃取法是稀土分离提纯的主要方法之一,但在工业生产过程中常因工艺条件控制不当而发生乳化现象。为了解决这一难题,研究了以表面活性剂Span 80为调控剂、P507为萃取剂、煤油为稀释剂萃取稀土,考察了水相pH、搅拌速度和水油相比对Er^(3+)萃取率和萃余液中油质量浓度的影响,并采用响应面法对工艺参数进行了优化。优化结果表明;在水相pH=3.5、搅拌速度130 r/min、水油相比4∶1优化条件下萃取5 min,Er^(3+)萃取率可达95.42%,萃余液中油质量浓度仅为1.68 mg/L,预测值与试验结果吻合度较高;加入Span 80能有效防止乳化现象发生,调控作用明显。 展开更多
关键词 P507 span 80 稀土 溶剂萃取 乳化 响应面法
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Span乳化稠油油水界面性能
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作者 唐珑 潘延东 +2 位作者 黄蒙 高荆维 张志秋 《化工科技》 2025年第5期21-26,50,共7页
针对油田注水开发中油井出水引发的低效循环问题,系统探究了原油组成性质对Span乳化稠油油水界面及其乳状液稳定性的影响。选取辽河油田2种稠油(1^(#)和2^(#))为研究对象,通过柱层析分离获得族组分,结合紫外光谱、红外光谱及气质联用技... 针对油田注水开发中油井出水引发的低效循环问题,系统探究了原油组成性质对Span乳化稠油油水界面及其乳状液稳定性的影响。选取辽河油田2种稠油(1^(#)和2^(#))为研究对象,通过柱层析分离获得族组分,结合紫外光谱、红外光谱及气质联用技术表征原油组成特征。实验采用单滴法评价界面膜强度,并借助偏光显微镜观察乳状液微观状态。结果表明,2^(#)原油沥青质+胶质含量显著高于1^(#)原油,其芳香烃组分中低环芳烃占比更高,利于沥青质分散及界面膜强化。系列Span乳化剂中Span80由于结构中的长碳链和双键结构使其在2^(#)原油体系中形成的界面膜强度最优(t1/2=333s)。微观分析表明,Span80/2^(#)体系形成的油包水(W/O)乳状液平均粒径较Span20体系明显减小,乳状液稳定性提高,Span乳化剂的结构对油水界面强度产生明显影响。 展开更多
关键词 乳化稠油 界面膜强度 span乳化剂
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基于span机制与动态解码策略的中文敏感信息识别方法
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作者 钱明熙 梁颖红 《金陵科技学院学报》 2025年第1期15-21,共7页
数字技术的快速发展导致中文敏感信息泄露风险加剧,而传统基于匹配规则和机器学习的方法在复杂实体边界和中文上下文处理时存在不足。针对中文敏感信息的命名实体识别问题提出了一种基于span机制和动态解码策略的改进模型,在BERT+BiLSTM... 数字技术的快速发展导致中文敏感信息泄露风险加剧,而传统基于匹配规则和机器学习的方法在复杂实体边界和中文上下文处理时存在不足。针对中文敏感信息的命名实体识别问题提出了一种基于span机制和动态解码策略的改进模型,在BERT+BiLSTM+CRF模型的基础上,加入span机制以更好地捕捉实体边界的位置信息。实验结果表明,相较于未加入span的基线模型,新模型的准确性和F1值显著提升,F1得分为96.7%,在处理长距离依赖关系和复杂实体时表现更加出色。 展开更多
关键词 中文敏感信息 命名实体识别 span机制 动态解码策略 上下文分析
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SPAN动态保证金模型下电力期货套期效果研究
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作者 苑秀娥 郝宇翔 《财会通讯》 北大核心 2025年第5期97-102,共6页
随着我国电力市场化不断推进,电力现货市场逐步放开,各区域电力现货市场加速转入正式运行。电力现货价格波动剧烈,需要开设电力期货商品发挥套期保值作用。电力期货是控制电力现货价格风险的重要金融衍生工具,期货保证金制度是期货商品... 随着我国电力市场化不断推进,电力现货市场逐步放开,各区域电力现货市场加速转入正式运行。电力现货价格波动剧烈,需要开设电力期货商品发挥套期保值作用。电力期货是控制电力现货价格风险的重要金融衍生工具,期货保证金制度是期货商品的核心制度,SPAN动态保证金系统下计算的动态保证金具备更强的风险控制能力。本文结合我国电力市场的特点,设计了电力期货动态保证金计算模型,运用套期会计分析了动态保证金模型下电力期货套期保值的效果,并为我国电力期货市场的建设提出建议。 展开更多
关键词 span动态保证金系统 电力期货 套期会计
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Life Span of Solutions for a Class of Semilinear Parabolic Equations with Large Initial Values
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作者 XUE Yingzhen LI Yulin 《Wuhan University Journal of Natural Sciences》 2025年第2期111-117,共7页
In this paper,a class of semilinear parabolic equations with cross coupling of power and exponential functions and large initial values are studied.By constructing and solving ordinary differential equations,the upper... In this paper,a class of semilinear parabolic equations with cross coupling of power and exponential functions and large initial values are studied.By constructing and solving ordinary differential equations,the upper and lower bounds on the solution life span of the equations areobtained. 展开更多
关键词 semilinear parabolic equations life span comparative principle blow up
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Incommensurate modulated structure and its influence on the martensitic transformation temperature span of single phase multielement Ni-Cu-Co-Mn-Ga two-way shape memory single crystals
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作者 Qijia Yu Yang Liu +5 位作者 Chen Si Wenjia Wang Jiaxi Meng Jingmin Wang Jinghua Liu Chengbao Jiang 《Journal of Materials Science & Technology》 2025年第5期230-240,共11页
Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence ... Significant two-way shape memory effect(TWSME)was achieved in single crystals of single-phase multielement Ni42-x Cu8 Cox Mn37 Ga13(8≤x≤12)alloys by performing thermomechanical training.However,anomalous dependence of the martensitic transformation temperature span on Co content was observed.Before training,quite a narrow temperature span of the martensitic transformation,nearly independent of the Co content,was observed in all single crystals.After training the temperature span was still narrow for 8≤x≤10.9 but was obviously expanded for 10.9<x≤12.High-resolution transmission electron microscopy revealed that at the atomic scale,there exists incommensurate modulated structure in the single phase single crystals,as evidenced by nonperiodic satellite spots in the selected area electronic diffraction patterns.Moreover,the modulated wave vector of the satellite spots was increased by higher Co contents.Combining first principal calculations it was considered that the incommensurate modulated structure originates from the formation of Co-Co pairs.After training arrays of ordered dislocations with the same Burgers vector were introduced for 8≤x≤10.9 but the network of dislocations was formed for 10.9<x≤12.Based on analysis of transmission electron microscopy,geometric phase,thermodynamics,and Landau theory,it was considered that the austenite/martensite phase interface was pinned by the network of dislocations,expanding the temperature span of the martensitic transformation.This work supplies new insights for understanding the microstructure and martensitic transformation of Ni-Mn-Ga-based alloys. 展开更多
关键词 Martensitic transformation Incommensurate modulated structure Temperature span DISLOCATION Two-way shape memory effect
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Span-80合成工艺的优化及溶液乳化性质研究
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作者 卢悦 刘岩 王洪国 《当代化工研究》 2025年第15期157-159,共3页
以山梨醇和油酸为原料,自制命名为BNA的催化剂对Span-80乳化剂合成工艺进行改进,实现了醚化酯化反应连续进行,通过系统优化反应参数(酸醇比、温度、时间、催化剂用量),成功制备了性能优异的Span-80产品。FT-IR结构表征证实产物具有标准S... 以山梨醇和油酸为原料,自制命名为BNA的催化剂对Span-80乳化剂合成工艺进行改进,实现了醚化酯化反应连续进行,通过系统优化反应参数(酸醇比、温度、时间、催化剂用量),成功制备了性能优异的Span-80产品。FT-IR结构表征证实产物具有标准Span-80分子结构。性能测试表明,该工艺制备的Span-80具有更低的临界胶束浓度和表面张力。 展开更多
关键词 span-80 合成工艺 表面张力 乳化性能 溶液分析
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Actionable Genotypes and Their Association with Life Span in Iceland
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作者 Brynjar O Jensson 《四川生理科学杂志》 2025年第11期2486-2486,共1页
Background:In 2021,the American College of Medical Genetics and Genomics(ACMG)recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available.... Background:In 2021,the American College of Medical Genetics and Genomics(ACMG)recommended reporting actionable genotypes in 73 genes associated with diseases for which preventive or therapeutic measures are available.Evaluations of the association of actionable genotypes in these genes with life span are currently lacking.Methods:We assessed the prevalence of coding and splice variants in genes on the ACMG Secondary Findings,version 3.0(ACMG SF v3.0),list in the genomes of 57,933 Icelanders.We assigned pathogenicity to all reviewed variants using reported evidence in the ClinVar database,the frequency of variants,and their associations with disease to create a manually curated set of actionable genotypes(variants).We assessed the relationship between these genotypes and life span and further examined the specific causes of death among carriers. 展开更多
关键词 Icelandic population genetic variants PATHOGENICITY life span coding splice variants actionable genotypes preventive therapeutic measures ACMG secondary findings
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基于RoBERTa-Span-Attack的标签指针网络军事命名实体识别 被引量:4
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作者 罗兵 张显峰 +1 位作者 段立 陈琳 《海军工程大学学报》 CAS 北大核心 2024年第1期76-82,93,共8页
军事领域文本中存在大量军事实体信息,准确识别这些信息是军事文本信息提取和构建军事知识图谱的基础性任务。首先,提出了一种基于RoBERTa预训练模型、跨度和对抗训练的标签指针网络的融合深度模型(RoBERTa-Span-Attack),用于中文军事... 军事领域文本中存在大量军事实体信息,准确识别这些信息是军事文本信息提取和构建军事知识图谱的基础性任务。首先,提出了一种基于RoBERTa预训练模型、跨度和对抗训练的标签指针网络的融合深度模型(RoBERTa-Span-Attack),用于中文军事命名实体识别;然后,采用了一种基于Span的标签指针网络,同时完成实体的起止位置和类别的识别任务;最后,在模型训练过程中加入对抗训练策略,通过添加一些扰动来生成对抗样本进行训练。在军事领域数据集上的实验结果表明:所提出的军事领域命名实体识别模型相较于BERT-CRF、BERT-Softmax和BERT-Span,在识别准确度上具有更优的效果。 展开更多
关键词 军事命名实体识别 预训练模型 跨度 标签指针网络 对抗训练
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A super-large graphite deposit discovered in granite rocks at Huangyangshan, Xinjiang,China 被引量:9
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作者 Jiang Ai Xin-biao Lu +1 位作者 Zuo-wu Li Ya-lun Wu 《China Geology》 2018年第1期164-166,共3页
1.Objective A graphite deposit has been discovered in Sujiquan, Xinjiang in 1980s,which provides detailed geological settings for the super-large graphite deposit discovered in Huangyangshan pluton with total reserves... 1.Objective A graphite deposit has been discovered in Sujiquan, Xinjiang in 1980s,which provides detailed geological settings for the super-large graphite deposit discovered in Huangyangshan pluton with total reserves up to 7.264×10^9 t in 2017.Outcrops of igneous rocks in the study area include Middle Devonian plagioclase granite and Late Carboniferous alkali feldspar granite that is referred to the Huangyangshan pluton,which includes the Lower Carboniferous Heishantou Formation and Jiangbasi Formation,both of which consist of volcanic-sedimentary rocks (Fig.1).Sujiquan fault provided passage for the migration of volcanic intrusions.Graphite deposits are usually hosted by metamorphic rocks,but Huangyanshan deposits are hosted by granite rocks,which are rarely known.The Huangyangshan graphite deposit hosted by granite pluton at Huangyangshan area was discovered by Xinjiang Branch of China National Geological Exploration Center of Building Materials Industry since 2015. 展开更多
关键词 super-large GRAPHITE DEPOSIT GRANITE ROCKS Huangyangshan
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Numerical simulation research on response characteristics of surrounding rock for deep super-large section chamber under dynamic and static combined loading condition 被引量:17
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作者 FAN De-yuan LIU Xue-sheng +3 位作者 TAN Yun-liang SONG Shi-lin NING Jian-guo MA Qing 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第12期3544-3566,共23页
The stability control of surrounding rock for large or super-large section chamber is a difficult technical problem in deep mining condition.Based on the in-site geological conditions of Longgu coal mine,this paper us... The stability control of surrounding rock for large or super-large section chamber is a difficult technical problem in deep mining condition.Based on the in-site geological conditions of Longgu coal mine,this paper used the dynamic module of FLAC3D to study the response characteristics of deep super-large section chamber under dynamic and static combined loading condition.Results showed that under the static loading condition,the maximum vertical stress,deformation and failure range are large,where the stress concentration coefficient is 1.64.The maximum roof-to-floor and two-sides deformations are 54.6 mm and 53.1 mm,respectively.Then,under the dynamic and static combined loading condition:(1)The influence of dynamic load frequency on the two-sides is more obvious;(2)The dynamic load amplitude has the greatest influence on the stress concentration degree,and the plastic failure tends to develop to the deeper;(3)With the dynamic load source distance increase,the response of surrounding rock is gradually attenuated.On this basis,empirical equations for each dynamic load conditions were obtained by using regression analysis method,and all correlation coefficients are greater than 0.99.This research provided reference for the supporting design of deep super-large section chamber under same or similar conditions. 展开更多
关键词 deep mining super-larger section chamber static load dynamic load frequency dynamic load amplitude dynamic load source distance
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Instability energy mechanism of super-large section crossing chambers in deep coal mines 被引量:5
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作者 Deyuan Fan Xuesheng Liu +2 位作者 Yunliang Tan Xuebin Li Purev Lkhamsuren 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2022年第5期1075-1086,共12页
The stress concentration and failure at chamber intersections in coal mine are intense,especially in deepburied,super-large section conditions.In this paper,the plastic radius of super-large section chamber under uneq... The stress concentration and failure at chamber intersections in coal mine are intense,especially in deepburied,super-large section conditions.In this paper,the plastic radius of super-large section chamber under unequal pressure was corrected on the basis of the size effect.Then,stress and failure evolution of intersections under different crossing angles and equivalent angular bisectors were revealed.Furthermore,2 trajectory curves of failure and stress were analytically expressed,which divided the intersection into 5 influencing zones in the light of stress superposition degree.After determining instability trigger point and instability path,instability energy criterion of intersection can be obtained as K>1,which means that the external energy is greater than the sum of energy consumed by surrounding rock instability and supporting structure failure.Taking coal-gangue separation system of Longgu Coal Mine as example,it was found that there was instability risk under original parameters.For long-term stability,an optimization design method was proposed by considering safety factor,and optimal support scheme was obtained.Field monitoring showed intersections deformations were relatively small with the maximum of 125 mm,which verified the rationality of theoretical analysis.This study provides guidance for the stability control of the intersections under the same or similar conditions. 展开更多
关键词 super-large section INTERSECTION Instability energy mechanism Optimization design Field monitoring
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Bainiuchang super-large silver-polymetallic ore deposit related to granitic magmatism in Mengzi, Yunnan 被引量:4
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作者 刘继顺 张洪培 +1 位作者 欧阳玉飞 张彩华 《Journal of Central South University of Technology》 EI 2007年第4期568-574,共7页
Bainiuchang silver-polymetallic ore deposit is located in the southeast Yunnan tin-polymetallic metallogenic belt.The probable reserves and inferred resources of the deposit are of 6 470 t Ag and 1.10 Mt Pb and 1.72 M... Bainiuchang silver-polymetallic ore deposit is located in the southeast Yunnan tin-polymetallic metallogenic belt.The probable reserves and inferred resources of the deposit are of 6 470 t Ag and 1.10 Mt Pb and 1.72 Mt Zn and 86 kt Sn.Orebodies of the deposit occur in clastic-carbonate rocks of Tianpeng Formation and Longha Formation of the middle Cambrian System above the Bainiuchang concealed granite of the late Yanshan period.The concealed granite has the characteristics of tin-bearing granites.Abundance of the mineralization elements Sn,Cu,Zn,Pb,Ag and Sb is high in the granitic rocks.Sulphur isotope data of the metal sulphides indicate that most sulphur is derived from the magmas.The ores are similar in rare earth element(REE)patterns to the granitic rocks.The granitic magma activity results in ore-bearing structures.Rocks of the Middle Cambrian System above the concealed intrusion suffer from skarnization,hornfelsing,marbleization,siliconizing and carbonatization.The mineralization elements Sn,Cu,Zn,Pb,Ag and Sb successively appear from the top of the granite to surrounding rocks.These evidences indicate that the granitic magmatism is the principal mineralization factor.The opinion that the south Bainiuchang ore field and the north Awei ore block are tin and copper potential exploration areas was put forward and was verified by drilling tests. 展开更多
关键词 BAINIUCHANG super-large silver-polymetallic deposit granite granitic-porphyry tin ore
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New Zircon U-Pb Age of the Super-Large Lijiagou Spodumene Deposit in Songpan Garze Fold Belt, Eastern Tibet: Implications for Early Jurassic Rare-Metal Polymetallic Event 被引量:8
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作者 FEI Guangchun TIAN Jingjing +4 位作者 YANG Jiyi GAO Jianguo TANG Wenchun LI Jian GU Chenghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2018年第3期1274-1275,共2页
Objective The Songpan-Garze Fold Belt(SGFB),located in the eastern part of the Tibet Plateau and west of the Sichuan Basin,is an important pegmatite province in China.Some famous pegmatite type deposits occur in the S... Objective The Songpan-Garze Fold Belt(SGFB),located in the eastern part of the Tibet Plateau and west of the Sichuan Basin,is an important pegmatite province in China.Some famous pegmatite type deposits occur in the SGFB,including the Xuebaoding,Jiajika,Keeryin rare metal deposits and Danba muscovite deposit(Li Jiankang et al.,2015).The newly discovered super-large Lijiagou 展开更多
关键词 New Zircon U-Pb Age of the super-large Lijiagou Jurassic Rare-Metal Polymetallic Event
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A Super-Large Rb-Nb Rare Metal Deposit has been Discovered in Huashi Village of Xinglong County, Hebei Province 被引量:3
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作者 LI Yujing XIE Wu +3 位作者 QI Yunfei MIAO Qunfeng XIONG Chao GONG Chuanwei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2344-2345,共2页
Objective The Huashi Village in Xinglong County of Hebei Province is located in the Yanshan subsidence zone in the central eastern North China Plate, which is 137 km away from Beijing City (Fig. la). This area has ... Objective The Huashi Village in Xinglong County of Hebei Province is located in the Yanshan subsidence zone in the central eastern North China Plate, which is 137 km away from Beijing City (Fig. la). This area has undergone large -scale magmatic intrusion affected by the tectonic compression of the Pacific Plate in the Mesozoic (known as the Yanshanian movement) to form many alkaline rocks such as the Wulingshan rock mass. Previous studies have conducted petrological research and reconnaissance survey of rare metal ores in this area (Tian Shuzhang and Guo Zongshan, 1981; Xu Baoling et al., 1996). In 2016, the Qinhuangdao Mineral and Hydrology Engineering Geological Brigade of Hebei Bureau of Geology and Mineral Resources Exploration implemented the project of Reconnaissance of Rare Metal Ores Including Rubidium in Huashi Village of Xinglong County, Hebei Province, and discovered super-large rare metal deposits of rubidium and biobium in the Madi alkali feldspar granite bodies in the Huashi Village to achieve great breakthrough of rare metal ore prospecting. 展开更多
关键词 A super-large Rb-Nb Rare Metal Deposit Huashi
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Wind-induced responses of super-large cooling towers 被引量:3
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作者 柯世堂 葛耀君 +2 位作者 赵林 陈少林 Y.Tamura 《Journal of Central South University》 SCIE EI CAS 2013年第11期3216-3228,共13页
Traditional gust load factor(GLF)method,inertial wind load(IWL)method and tri-component method(LRC+IWL)cannot accurately analyze the wind-induced responses of super-large cooling towers,so the real combination formula... Traditional gust load factor(GLF)method,inertial wind load(IWL)method and tri-component method(LRC+IWL)cannot accurately analyze the wind-induced responses of super-large cooling towers,so the real combination formulas of fluctuating wind-induced responses and equivalent static wind loads(ESWLSs)were derived based on structural dynamics and random vibration theory.The consistent coupled method(CCM)was presented to compensate the coupled term between background and resonant response.Taking the super-large cooling tower(H=215 m)of nuclear power plant in Jiangxi Province,China,which is the highest and largest in China,as the example,based on modified equivalent beam-net design method,the aero-elastic model for simultaneous pressure and vibration measurement of super-large cooling tower is firstly carried out.Then,combining wind tunnel test and CCM,the effects of self-excited force on the surface pressures and wind-induced responses are discussed,and the wind-induced response characteristics of background component,resonant component,coupled term between background and resonant response,fluctuating responses,and wind vibration coefficients are discussed.It can be concluded that wind-induced response mechanism must be understood to direct the wind resistant design for super-large cooling towers. 展开更多
关键词 super-large cooling towers wind-induced responses wind vibration coefficients aero-elastic model consistent coupled method
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基于对span的预判断和多轮分类的实体关系抽取 被引量:1
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作者 佟缘 姚念民 《计算机工程与科学》 CSCD 北大核心 2024年第5期916-928,共13页
针对自然语言处理领域中的实体识别和关系抽取任务,提出一种对词元序列(Token Sequence,又称span)进行预测的模型Smrc。模型整体上利用BERT预训练模型作为编码器,另外包含实体预判断(Pej)、实体多轮分类(Emr)和关系多轮分类(Rmr)3个模块... 针对自然语言处理领域中的实体识别和关系抽取任务,提出一种对词元序列(Token Sequence,又称span)进行预测的模型Smrc。模型整体上利用BERT预训练模型作为编码器,另外包含实体预判断(Pej)、实体多轮分类(Emr)和关系多轮分类(Rmr)3个模块。Smrc模型通过Pej模块的初步判断及Emr模块的多轮实体分类来进行实体识别,再利用Rmr模块的多轮关系分类来判断实体对间的关系,进而完成关系抽取任务。在CoNLL04、SciERC和ADE 3个实验数据集上,Smrc模型的实体识别F1值分别达到89.67%,70.62%和89.56%,关系抽取F1值分别达到73.11%,51.03%和79.89%,相较之前在3个数据集上的最佳模型Spert,Smrc模型凭借实体预判断和实体及关系多轮分类,在2个子任务上其F1值分别提高了0.73%,0.29%,0.61%及1.64%,0.19%,1.05%,表明了该模型的有效性及其优势。 展开更多
关键词 span的预判断 实体关系抽取 BERT预训练模型 多轮实体分类 多轮关系分类
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Two Super-Large Gold Deposits Have Been Discovered in Jiaodong Peninsula of China 被引量:3
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作者 HAO Ziguo FEI Hongcai +1 位作者 HAO Qingqing LIU Lian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第1期368-369,共2页
During 2015, gold prospecting in Laizhou City of Shandong Peninsula in China has achieved a major breakthrough. Deposits containing 470 and 389 tons of gold metal were discovered in the northern sea area of Sanshandao... During 2015, gold prospecting in Laizhou City of Shandong Peninsula in China has achieved a major breakthrough. Deposits containing 470 and 389 tons of gold metal were discovered in the northern sea area of Sanshandao and the Shaling area, respectively. As a result, the gold prospective resources in the entire Jiaodong Peninsula have now exceeded 4000 tons, fully indicative of the super-large prospecting potential of the Jiaojia-type deposits. 展开更多
关键词 GOLD Two super-large Gold Deposits Have Been Discovered in Jiaodong Peninsula of China
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Magmatic Evolution and Mineralization Process of the Super-Large Shihuiyao Rb–Nb–Ta Deposit,Southern Great Xing'an Range,China 被引量:3
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作者 ZHOU Zhenhua CHE Hewei +1 位作者 MA Xinghua GAO Xu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第6期2275-2276,共2页
Rare metal ore reserves are an important strategic resource, and their metallogenic mechanism and mineralization studies have also been received widespread international attention.
关键词 In Nb Magmatic Evolution and Mineralization Process of the super-large Shihuiyao Rb Ta Deposit Southern Great Xing’an Range China
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The Major Ore Clusters of Super-Large Iron Deposits in the World, Present Situation of Iron Resources in China, and Prospect 被引量:2
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作者 ZHAO Yiming FENG Chengyou LI Daxin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1895-1915,共21页
The metamorphosed sedimentary type of iron deposits(BIF) is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Caraj... The metamorphosed sedimentary type of iron deposits(BIF) is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Carajas in Brazil, Hamersley in Australia, Kursk in Russia, Central Province of India and Anshan-Benxi in China. Subordinated types of iron deposits are magmatic, volcanic-hosted and sedimentary ones. This paper briefly introduces the geological characteristics of major super-large iron ore clusters in the world. The proven reserves of iron ores in China are relatively abundant, but they are mainly low-grade ores. Moreover, a considerate part of iron ores are difficult to utilize for their difficult ore dressing, deep burial or other reasons. Iron ore deposits are relatively concentrated in 11 metallogenic provinces(belts), such as the Anshan-Benxi, eastern Hebei, Xichang-Central Yunnan Province and middle-lower reaches of Yangtze River. The main minerogenetic epoches vary widely from the Archean to Quaternary, and are mainly the Late Archean to Middle Proterozoic, Variscan, and Yanshanian periods. The main 7 genetic types of iron deposits in China are metamorphosed sedimentary type(BIF), magmatic type, volcanic-hosted type, skarn type, hydrothermal type, sedimentary type and weathered leaching type. The iron-rich ores occur predominantly in the skarn and marine volcanic-hosted iron deposits, locally in the metamorphosed sedimentary type(BIF) as hydrothermal reformation products. The theory of minerogenetic series of mineral deposits and minerogenic models has applied in investigation and prospecting of iron ore deposits. A combination of deep analyses of aeromagnetic anomalies and geomagnetic anomalies, with gravity anomalies are an effective method to seeking large and deep-buried iron deposits. China has a relatively great oresearching potential of iron ores, especially for metamorphosed sedimentary, skarn, and marine volcanic-hosted iron deposits. For the lower guarantee degree of iron and steel industry, China should give a trading and open the foreign mining markets. 展开更多
关键词 major ore clusters of super-large iron deposits present situation of iron ore resources in China genetic type temporal-spatial distribution ore-searching potential
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