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In situ construction of a stable composite solid electrolyte interphase for dendrite-free Zn batteries 被引量:2
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作者 Yiming Zhao Huanyan Liu +4 位作者 Yu Huyan da lei Na Li Shan Tian Jian-Gan Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第4期450-458,共9页
Building a stable solid electrolyte interphase(SEI)has been regarded to be highly effective for mitigating the dendrite growth and parasitic side reactions of Zn anodes.Herein,a robust inorganic composite SEI layer is... Building a stable solid electrolyte interphase(SEI)has been regarded to be highly effective for mitigating the dendrite growth and parasitic side reactions of Zn anodes.Herein,a robust inorganic composite SEI layer is in situ constructed by introducing an organic cysteine additive to achieve long lifetime Zn metal batteries.The chemisorbed cysteine derivatives are electrochemically reduced to trigger a local alkaline environment for generating a gradient layered zinc hydroxide based multicomponent interphase.Such a unique interphase is of significant advantage as a corrosion inhibitor and Zn^(2+)modulator to enable reversible plating/stripping chemistry with a reduced desolvation energy barrier.Accordingly,the cells with a thin glass fiber separator(260μm)deliver a prolonged lifespan beyond 2000 h and enhanced Coulombic efficiency of 99.5%over 450 cycles.This work will rationally elaborate in situ construction of a desirable SEI by implanting reductive additives for dendrite-free Zn anodes. 展开更多
关键词 Zn metal anode Electrolyte additive Solid electrolyte interphase Aqueous Zn batteries
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腹横肌平面阻滞联合右美托咪定复合舒芬太尼静脉镇痛对肝部分切除术后早期康复的影响 被引量:14
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作者 笪磊 谢言虎 +2 位作者 柴小青 章蔚 魏昕 《临床麻醉学杂志》 CAS CSCD 北大核心 2018年第12期1164-1167,共4页
目的评估腹横肌平面阻滞(transversus abdominis plane block,TAPB)联合舒芬太尼、右美托咪定用于肝部分切除患者术后镇痛的效果和安全性,探讨其对患者术后早期康复的影响。方法选择择期行肝部分切除术患者60例,男31例,女29例,年龄20~6... 目的评估腹横肌平面阻滞(transversus abdominis plane block,TAPB)联合舒芬太尼、右美托咪定用于肝部分切除患者术后镇痛的效果和安全性,探讨其对患者术后早期康复的影响。方法选择择期行肝部分切除术患者60例,男31例,女29例,年龄20~65岁,BMI 18~25kg/m^2,ASAⅠ或Ⅱ级。采用随机数字表法分为两组,术后自愿行静脉自控镇痛,A组舒芬太尼2μg/kg;B组右美托咪定1μg/kg+舒芬太尼2μg/kg。两组均行超声引导下TAPB,给予0.375%罗哌卡因20ml。记录术后48h内VAS疼痛评分和Ramsay镇静评分,术后肠道恢复通气时间、术后进食时间、术后住院时间及并发症发生情况等。结果与A组比较,B组术后12、24h静息VAS评分及术后12、48h运动VAS评分明显降低(P<0.05);B组术后首次排气时间、术后进食时间、术后住院时间明显缩短(P<0.05)。两组术后Ramsay镇静评分及恶心、呕吐、低血压、心动过缓、呼吸抑制、肺部感染等发生率差异无统计学意义。结论对于行肝部分切除手术的患者,TAPB联合右美托咪定复合舒芬太尼用于术后镇痛可加速患者术后早期康复。 展开更多
关键词 术后镇痛 腹横肌平面阻滞 右美托咪定 舒芬太尼 加速康复外科
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全媒体时代网络舆情治理研究 被引量:7
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作者 笪蕾 《学术前沿》 CSSCI 北大核心 2020年第9期108-111,共4页
全媒体时代呼啸而至,舆论生态和媒体格局都发生了翻天覆地的变革,网络舆情治理成为社会治理当中不容忽视的题中之义。本文从网络舆情治理的概念出发,试图辨析其本质内涵,以此为基础讨论全媒体时代背景下网络舆情治理在主体、速度、手段... 全媒体时代呼啸而至,舆论生态和媒体格局都发生了翻天覆地的变革,网络舆情治理成为社会治理当中不容忽视的题中之义。本文从网络舆情治理的概念出发,试图辨析其本质内涵,以此为基础讨论全媒体时代背景下网络舆情治理在主体、速度、手段和制度方面的困境问题。网络舆情治理是一个系统工程,需要从完善法律法规体系,提高多元治理主体协同性,以及加强治理主体行为规范性等方面入手,有效避免信息时代网络舆情为社会带来的各种负面影响,营造一个和谐有序的网络社会,构筑全媒体时代网络舆情治理的"同心圆",全面提升我国网络舆情治理水平。 展开更多
关键词 全媒体时代 网络舆情 舆情治理
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Competing reduction induced homogeneous oxygen doping to unlock MoS_(2)basal planes for faster polysulfides conversion 被引量:2
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作者 da lei Wenzhe Shang +10 位作者 Xu Zhang Yongpeng Li Xiaoshan Shi Shaoming Qiao Qian Wang Qiang Zhang Ce Hao Hui Xu Guohua Chen Gaohong He Fengxiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第10期26-34,I0002,共10页
The parasitic polysulfides shuttle effect greatly hinders the practical application of lithium sulfur batteries,and this issue can be addressed by promoting polysulfides conversion with catalytic materials such as Mo ... The parasitic polysulfides shuttle effect greatly hinders the practical application of lithium sulfur batteries,and this issue can be addressed by promoting polysulfides conversion with catalytic materials such as Mo S_(2).However,the catalytic activity of Mo S_(2)mainly relies on edge sites,but is limited by inert basal planes.We herein report a novel,facile,ethylene glycol enabled competing reduction strategy to dope Mo S_(2)homogeneously with oxygen atoms so that its inert basal planes can be unlocked.Ethylene glycol works as a reducing agent and competes with thiourea to react with ammonium molybdate,leading to insufficient sulfuration of Mo,and consequent formation of O-Mo S_(2).Our theoretical and experimental investigations indicate that the homogeneously distributed O dopants can create abundant adsorption/-catalytic sites in the Mo S_(2)basal planes,enlarge the inter-plane distance to promote ion transport,and thus enhance the catalytic conversion of polysulfides.The oxygen doped Mo S_(2)(O-Mo S_(2))is supported on carbon nanosheets(CNS)and the composite(O-Mo S_(2)/CNS)is employed to modify the separator of Li-S battery.It gives the battery an initial discharge capacity of 1537 m Ah g-1at 0.2 C,and the battery retains a discharge capacity of 545 m Ah g-1after ultra-long 2000 cycles at 1 C,corresponding to a very small cyclic decay rate of 0.0237%.Even under a raising sulfur loading of 8.2 mg cm^(-2),the Li-S battery also delivers a high discharge capacity(554 m Ah g^(-1))with outstanding cycle stability(84.6%capacity retention)after 100 cycles at 0.5 C.Our work provides a novel,facile approach to fabricate highly catalytically active oxygen-doped Mo S_(2)for advanced Li-S batteries. 展开更多
关键词 Competing reduction One-pot Oxygen-doped MoS_(2) Unlocked basal plane Li-S batteries
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Physiological Testosterone Retards Cardiomyocyte Aging in Tfm Mice via Androgen Receptor-independent Pathway 被引量:1
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作者 Li Zhang da lei +2 位作者 Gui-ping Zhu lei Hong Sai-zhu Wu 《Chinese Medical Sciences Journal》 CAS CSCD 2013年第2期88-94,共7页
Objective To determine whether testosterone modulates markers of cardiomyocytes aging via its classic androgen receptor (AR)-dependent pathway or conversion to estradiol.Methods Male littermates and testicular feminiz... Objective To determine whether testosterone modulates markers of cardiomyocytes aging via its classic androgen receptor (AR)-dependent pathway or conversion to estradiol.Methods Male littermates and testicular feminized (Tfm) mice were randomly separated into 4 experimental groups:littermate controls (n=8),Tfm mice (n=7),testosterone-treated Tfm mice (n=8),and Tfm mice treated with testosterone in combination with the aromatase inhibitor anastrazole (n=7).Cardiomyocytes were isolated from mouse left ventricles,the activity of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px),and the amount of malondialdehyde (MDA) were measured using colorimetry method,and expression of p16 INK4 α and retinoblastoma (Rb) proteins were detected by Western blotting.Results The SOD and GSH-Px enzyme activities of cardiomyocytes were decreased,and the MDA levels and the expression of p16 INK4 α and Rb proteins were increased in Tfm mice compared with control mice.An increase was observed in the activities of SOD and GSH-Px enzyme as well as a decrease in MDA levels and the expression of p16 INK4 α and Rb proteins in the testosterone-treated Tfm mice.After co-treatment with anastrazole in Tfm mice,these improvement were partly inhibited.Conclusion Physiological testosterone replacement can delay cardiomyocyte aging in Tfm mice,an effect that is independent of the AR pathway and in part conversion to estradiol. 展开更多
关键词 心肌细胞 雄激素受体 TFM 细胞老化 小鼠 睾酮 延缓 生理
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Prediction of Aircraft Engine Health Condition Parameters Based on Ensemble ELM 被引量:1
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作者 da lei Shi-Sheng Zhong 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第3期7-11,共5页
In view of aircraft engine health condition parameters prediction,an ensemble ELM based prediction approach is proposed in this paper. In the approach,the AdaBoost. RT algorithm is improved to adjust its threshold ada... In view of aircraft engine health condition parameters prediction,an ensemble ELM based prediction approach is proposed in this paper. In the approach,the AdaBoost. RT algorithm is improved to adjust its threshold adaptively,and is utilized as the basic framework to establish the ensemble learning model using ELM as weak learners. The proposed approach is evaluated through the prediction of the actual engine fuel flow deviation time series,and the results demonstrate that this approach is feasible for the prediction of aircraft engine health condition parameters. The performance of the proposed approach is compared with single ELM, single process neural network ( PNN) ,and a similar ensemble ELM based approach using AdaBoost. RT as basic framework. The results show that,the proposed approach is more accurate than single ELM and single PNN,and no worse than the ensemble prediction approach for contrast,furthermore,the given approach is more convenient for practical application. Therefore,the proposed approach is better suited to the prediction of aircraft engine health parameters. 展开更多
关键词 ensemble learning AdaBoost. RT ELM aircraft engine condition parameter prediction
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Quaternized polymer binder for lithium-sulfur batteries:The effect of cation structure on battery performance
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作者 Fang Wang Lv Li +4 位作者 da lei Yongpeng Li He Yang Weili Zhu Fengxiang Zhang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第4期165-172,共8页
Lithium–sulfur (Li–S) batteries are great candidates for energy storage systems, but need to overcome theissues of low sulfur utilization and polysulfide shuttling for use in large-scale commercial applications.Rece... Lithium–sulfur (Li–S) batteries are great candidates for energy storage systems, but need to overcome theissues of low sulfur utilization and polysulfide shuttling for use in large-scale commercial applications.Recently, quaternized polymers have received much attention for their polysulfide trapping propertiesdue to electrostatic interaction. In this work, we report a series of polyarylether sulfone (PSF) binderswith different cation structures including imidazolium (Im), triethylammonium (Tr), and morpholinium(Mo). The ability of the these quaternized binders and the conventional poly(vinylidene fluoride) or PVDFbinder to capture polysulfide increases in the order of PVDF << PSF-Mo < PSF-Tr< PSF-Im. The delocalizedcharge on the imidazolium cation may promote the interaction between PSF-Im and polysulfide asindicated by an X-ray photoelectron spectroscopic study. The PSF-Im based cathodes showed the highestcapacity retention (77% at 0.2 C after 100 cycles and 84% at 0.5 C after 120 cycles), and the bestrate capability. This work demonstrates the importance of the cation structure in the design of efficientquaternized binders for high performance Li–S batteries. 展开更多
关键词 Quaternized BINDER POLYSULFIDE Cycle stability Li-S battery
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A test method for analyzing the deformation of landslide model
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作者 da lei Mingjie Chen +4 位作者 Zhihao Xu Bin Luo Guanlu Jiang Kai Fan Qihao Zhou 《Earthquake Research Advances》 CSCD 2021年第3期46-52,共7页
In order to study the overall deformation of geotechnical model conveniently,the worksite of landslide bridge foundation reinforced by the front and rear row anti-slide piles in Chenglan railway was taken as an exampl... In order to study the overall deformation of geotechnical model conveniently,the worksite of landslide bridge foundation reinforced by the front and rear row anti-slide piles in Chenglan railway was taken as an example.On the basis of shaking tabe test of a 1/40 reduced scale model,the landslide deformation caused by vibration waves was monitored through burying self-made phosphor bronze strips in soil.Combined with the horizontal and vertical coordinates of the bending strain points on the phosphor bronze strips,the digital matrix was converted by applying Renka Cline random matrix generation method,and the two-dimensional contour plots were drawn based on it.The results showed that the two-dimensional contour plots reflected the basic law of landslide deformation reasonably,and it revealed the evolution process of landslide deformation and failure.The research conclusions were consistent with the test phenomenon,which met the basic requirements of overall deformation analysis of landslide model.This proposed method can monitor multiple cross sections and was practical for model test. 展开更多
关键词 LANDSLIDE Soil deformation Shaking table test Phosphor bronze strip Two-dimensional contour plot
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中华优秀传统文化与高校教育管理融合探析
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作者 刘波 笪蕾 《中国文化与管理》 2022年第1期191-197,231,共8页
当代高校管理人员在教育管理过程中,常会遇到各类制约教育管理效能的问题,影响着高校的健康发展。面对此种境况,高校教育急需具有深邃管理能力的思想文化对落后理念进行拨乱反正,而中华优秀传统文化所蕴含的中国特色的教育管理思想,不... 当代高校管理人员在教育管理过程中,常会遇到各类制约教育管理效能的问题,影响着高校的健康发展。面对此种境况,高校教育急需具有深邃管理能力的思想文化对落后理念进行拨乱反正,而中华优秀传统文化所蕴含的中国特色的教育管理思想,不仅包含经典的管理思想、原则,还囊括众多的管理策略和方法,因此,将中华优秀传统文化与高校教育融合,是提高其教育管理水平的有效途径。 展开更多
关键词 中华优秀传统文化 高校教育 融合
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The genesis and resource potential of gold deposits in the Liaodong Peninsula
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作者 Rixiang ZHU Jin-Hui YANG +7 位作者 Gongwen WANG Qingdong ZENG Guoqiang XUE Tao XU Xinghui LI Peng ZHANG da lei Guang ZHU 《Science China Earth Sciences》 SCIE EI CAS CSCD 2024年第3期657-672,共16页
Plenty of gold deposits related to Late Mesozoic craton destruction are widely distributed in eastern North China Craton. However, significant differences in research degrees, ore-forming characteristics, and proven r... Plenty of gold deposits related to Late Mesozoic craton destruction are widely distributed in eastern North China Craton. However, significant differences in research degrees, ore-forming characteristics, and proven reserves exist among different regions in the North China Craton. The Liaodong Peninsula has similar regional geological characteristics to those of the Jiaodong Peninsula, with both experiencing craton destruction during Late Mesozoic, but the two areas have substantial differences in terms of gold mineralization and the proven gold resources. Based on regional geology, Mesozoic magmatictectonic evolution and ore geology, combined with integrated geophysical exploration and big data AI resource prediction, in this paper, we propose that the ore-forming materials of Late Mesozoic gold deposits in Liaodong were mainly originated from mantle-derived melts and/or fluids induced by craton destruction. The gold deposits were primarily controlled by NE-NNEtrending faults, mainly classified as fracture-controlled altered rock-type and sulfide-bearing quartz vein-type. Moreover, our study predicts that the Yalu River fault zone and its related secondary faults, as well as the periphery and deeper parts of known goldfields, are the important regions for future gold resource exploration. The Yalu River metallogenic belt has an enormous potential for gold resources, and the Liaodong Peninsula has a potential to add thousands of tons of gold resources. 展开更多
关键词 Liaodong Peninsula Gold deposit Integrated geophysical exploration Prospecting potential Direction for prospecting breakthroughs
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Regulation of pseudographitic carbon domain to boost sodium energy storage
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作者 Zhidong Hou Mingwei Jiang +3 位作者 da lei Xiang Zhang Yuyang Gao Jian-Gan Wang 《Nano Research》 SCIE EI CSCD 2024年第6期5188-5196,共9页
Hard carbon anode has shown extraordinary potentials for sodium-ion batteries(SIBs)owing to the cost-effectiveness and advantaged microstructure.Nevertheless,the widespread application of hard carbon is still hindered... Hard carbon anode has shown extraordinary potentials for sodium-ion batteries(SIBs)owing to the cost-effectiveness and advantaged microstructure.Nevertheless,the widespread application of hard carbon is still hindered by the insufficient sodium storage capacity and depressed rate property,which are mainly induced by the undesirable pseudographitic structure.Herein,we develop a molten-salt-mediated strategy to regulate the pseudographitic structure of hard carbon with suitable interlayer spacing and enlarged pseudographitic domain,which is conducive to the intercalation capacity and diffusion kinetics of sodium ions.Impressively,the optimized hard carbon anode delivers a high reversible capacity of 320 mAh·g^(−1),along with superior rate property(138 mAh·g−1 at 2 A·g^(−1))and stable cyclability over 1800 cycles.Moreover,the in situ Raman spectroscopic study and full-cell assembly further investigate the sodium storage mechanism and practical implement of obtained hard carbon.This work pioneers a low-cost and effective route to regulate the pseudographitic structure of hard carbon materials for advanced SIBs. 展开更多
关键词 pseudographitic structure molten salt hard carbon ANODE sodium-ion batteries
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A family of oligo(p-phenylenevinylene)derivative aggregation-induced emission probes:Ultrasensitive,rapid,and anti-interfering fluorescent sensing of perchlorate via precise alkyl chain length modulation
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作者 Fangfang Xiao Yushu Li +5 位作者 Jiguang Li da lei Guangfa Wang Tianshi Zhang Xiaoyun Hu Xincun Dou 《Aggregate》 2023年第2期183-192,共10页
The precise regulation of interactions provided by aggregation-induced emission(AIE)probes is of considerable significance for improving the sensing performance in the field of on-site detection.Here,a highly sensitiv... The precise regulation of interactions provided by aggregation-induced emission(AIE)probes is of considerable significance for improving the sensing performance in the field of on-site detection.Here,a highly sensitive perchlorate detection probe was designed by precisely modulating the van der Waals interactions by adjusting the length of the alkyl chain.The optimized AIE probe demonstrated superior perchlorate detection performance owing to its strong van der Waals interactions with perchlorate,including a low detection limit(53.81 nM),rapid response(<5 s),and excellent specificity even in the presence of 16 interfering anions.In addition,a hydrogel-based device loaded with the probe was constructed to achieve ultrasensitive recognition of perchlorate particles with a detection limit as low as 15 fg under a fluorescence microscope.Moreover,the practicality of the probe was further verified by employing a sensing chip in a portable detector,and thus the probe has been proven to be highly promising for trace perchlorate monitoring in real scenarios.We expect the present study to be of great value for the efficient design of high-performance fluorescent probes. 展开更多
关键词 aggregation-induced emission explosive detection fluorescent probe PERCHLORATE trace sensing
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Intermolecular through-space charge transfer enabled by bicomponent assembly for ultrasensitive detection of synthetic cannabinoid JWH-018
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作者 Chaogan Liu Fangfang Xiao +5 位作者 Yushu Li da lei Yuan Liu Xiaowei Ma Chengzhi Gu Xincun Dou 《Aggregate》 2023年第4期128-137,共10页
Launching the intermolecular through-space charge transfer(TSCT)from a bicomponent assembly for photophysical property manipulation is of great significance in fluorescence probe design.Here,we demonstrate the elabora... Launching the intermolecular through-space charge transfer(TSCT)from a bicomponent assembly for photophysical property manipulation is of great significance in fluorescence probe design.Here,we demonstrate the elaborate control of droplet evaporation dynamics for intermolecular TSCT can facilitate the ultrasensitive detection of JWH-018,a representative synthetic cannabinoid.Driven by diverse intermolecular interactions,the probe,and JWH-018 assemble in a closely stacked manner to emit strong fluorescence at 477 nm,ascribing to the intermolecular TSCT at the S2 state.The strategy realizes an ultra-low limit of detection of 11 nmol/mL and great selectivity towards JWH-018.The practicability is further verified by constructing a sensing chip for JWH-018 aerosol detection,which facilitates the on-site drug abuser screening with the naked eye.Moreover,the proposed assembly-enabled TSCT is expected to find a variety of applications for optoelectronic materials design and photophysical mechanism-dominated molecular recognition. 展开更多
关键词 bicomponent assembly fluorescent sensing intermolecular interaction
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我国政治认同研究的发展脉络与趋势——基于CiteSpace知识图谱的分析 被引量:10
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作者 笪蕾 《江西社会科学》 CSSCI 北大核心 2020年第3期203-210,256,共9页
随着我国社会转型与全球化的加速进程,我国公民逐渐凸显政治认同方面的问题,政治认同成为当前政治学研究的重要课题。因此,梳理、提炼中国政治认同的研究历程和研究热点,是我国政治认同研究进一步发展的基础。借助CiteSpace软件,分析中... 随着我国社会转型与全球化的加速进程,我国公民逐渐凸显政治认同方面的问题,政治认同成为当前政治学研究的重要课题。因此,梳理、提炼中国政治认同的研究历程和研究热点,是我国政治认同研究进一步发展的基础。借助CiteSpace软件,分析中文核心期刊和CSSCI来源期刊上以"政治认同"为主题的724篇文献,可以看出,"政治认同"的主题在我国的学术关注度逐年提升,当前学界对政治认同的文献研究从理论层面逐渐过渡到实践层面,并且能够从微观角度、量化分析对政治认同进行深入研究。研究集中在政治认同的内涵、类型、来源、危机、重构和主体共六个热点主题,但仍要克服地域限制,加强人才交流,打造研究团队,促进我国政治认同研究继续深入而广泛的开展。 展开更多
关键词 政治认同 CiteSpace5.3.R6 知识图谱 文献计量分析
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Summary of technology for a comprehensive geophysical exploration of gold mine in North China Craton 被引量:3
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作者 Qingyun DI Guoqiang XUE +3 位作者 da lei Qingdong ZENG Changmin FU Zhiguo AN 《Science China Earth Sciences》 SCIE EI CSCD 2021年第9期1524-1536,共13页
The North China Craton is the oldest continental block,and has suffered from large-scale lithospheric thinning and destruction,which in turn led to gold deposits in northern China.The decratonic gold deposits in the N... The North China Craton is the oldest continental block,and has suffered from large-scale lithospheric thinning and destruction,which in turn led to gold deposits in northern China.The decratonic gold deposits in the North China Craton became the most important gold deposits in China,and geophysical methods are key means to detect and discover gold deposits there.In this paper,based on the geological and petrophysical characteristics of the North China Craton,the geological model of the decratonic gold deposits is transformed into a geophysical model.At present,two methods of geophysical exploration of decratonic gold deposits are in use:rapid and efficient exploration on the scale of the ore concentration area,and large depth exploration on the scale of the deposit area.In detail,the airborne electromagnetic,magnetic and gravity methods are used to detect the shallow(1,500 m)anomaly area on the scale of the ore concentration area.Through the ground-controlled source electromagnetic and ground magnetotelluric methods,explorations for targets at significant depth(5,000 m)are carried out in the mining area.Then,taking the Liaodong ore concentration area as an example,geophysical methods are used to discover two prospecting areas around the Jianshanzi Fault in the Qingchengzi ore concentration area,Baiyun-Xiaotongjiapuzi deep prospecting area,and Qingchengzi deep prospecting area.Next,three prospecting areas are delineated around the Jixingou Fault in the Wulong mining area,Wulong deep prospecting area,Weishagou deep prospecting area,and Chang’an deep prospecting area.The anomalies in the ore concentration area and mining area are revealed by means of three-dimensional exploration methods,thereby providing technical support for the exploration of metal minerals such as decratonic gold deposits. 展开更多
关键词 Decratonic gold deposits in the North China Craton Liaodong area Integrated geophysics Mining area scale Deposit area scale
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Design of packing cup interference fit value of hypercompressors for low density polyethylene production
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作者 da lei Xuehong LI +1 位作者 Yun LI Xiwen REN 《Frontiers in Energy》 SCIE CSCD 2019年第1期107-113,共7页
The hypercompressor is one of the core facilities in low density polyethylene production,with a discharge pressure of approximately 300 MPa.A packing cup is the basic unit of cylinder packing,assembled by the interfer... The hypercompressor is one of the core facilities in low density polyethylene production,with a discharge pressure of approximately 300 MPa.A packing cup is the basic unit of cylinder packing,assembled by the interference fit between an inner cup and an outer cup.Because the shrink-fitting prestresses the packing cup,serious design is needed to gain a favorable stress state,for example,a tri-axial compressive stress state.The traditional method of designing the interference fit value for packing cups depends on the shrink-fit theory for thickwalled cylinder subject to internal and external pressure.According to the traditional method,critical points are at the inner radii of the inner and external cup.In this study,the finite element method(FEM)has been implementcd to determine a more accurate stress level of packing cups.Different critical points have been found at the edge of lapped sealing surfaces between two adjacent packing cups.The maximum Von Mises equivalent stress in a packing cup increases after a decline with the rise of the interference fit value.The maximum equivalent stress initially occurs at the bore of the inner cup,then at the edge of lapped mating surfaces,and finally at the bore of the outer cup,as the interference radius increases.The traditional method neglects the influence of axial preloading on the interference mating pressure.As a result,it predicts a lower equivalent stress at the bore of the external cup.A higher interference fit value accepted by the traditional method may not be feasible as it might already make packing cups yield at the edge of mating surfaces or the bore of the external cup.Along with fatigue analysis,the feasible range of interference fit value has been modified by utilizing FEM.The modified range tends to be narrower and safer than the one derived from the traditional method,after getting rid of shrink-fit values that could result in yielding in a real packing cup. 展开更多
关键词 INTERFERENCE FIT VALUE PACKING CUP hypercompressor FINITE element method(FEM)
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