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Push-pull extraction strategy using DTPA as a complexing agent for enhanced separation of lutetium and ytterbium 认领 引用
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作者 Zilong Yang Jingquan Cai +2 位作者 Chuanying Liu Shuainan Ni Chengliang Xiao 《Journal of Rare Earths》 SCIE EI CAS CSCD 2026年第6期1907-1914,I0008,共8页
The efficient separation of lutetium(Lu)and ytterbium(Yb)re mains a significant challenge in rare earth elements processing due to their nearly identical chemical properties.In this work,a"push-pull"synergis... The efficient separation of lutetium(Lu)and ytterbium(Yb)re mains a significant challenge in rare earth elements processing due to their nearly identical chemical properties.In this work,a"push-pull"synergistic extraction system was developed,utilizing a mixture of phosphate ester extractants(named HP350)as the extractant and diethylenetriamine-N,N,N',N",N"-pentaacetic acid(DTPA)as the watersoluble complexing agent,aiming to achieve a higher selective separation of Lu3+and Yb3+.The effects of HP350 and DTPA concentrations,the equilibrium pH of the aqueous phase,and the extraction equilibration time on the separation performance of Lu3+/Yb3+ were systematically investigated.Notably,under the optimal conditions,the separation factor of Lu/Yb(SFLu/Yb)in the HP350-DTPA"push-pull"extraction system reaches 2.58±0.08,compared to only 1.81 with HP350 extractant alone.This result also greatly exceeds most of the extractants reported so far.Besides,the thermodynamic modeling results provide additional evidence that the presence of DTPA in the aqueous phase enhances the SFLu/Yb.The stripping experiment demonstrates that the SFLu/Yb of DTPA as a scrubbing agent is comparable to that of the extraction stage.Batch counter-current extraction experiments further confirm the efficacy of the"push-pull"extraction strategy,with the purity of Lu increasing from 48.0 wt%to 97.4 wt%after 10 extraction stages and 10 scrubbing stages.This study offers a novel approach to the efficient separation of Lu and Yb and demonstrates the potential of the"push-pull"extraction system in rare earth separation processes. 展开更多
关键词 Rare earths Lu/Yb separation Solvent extraction "Push-pull"effect
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Mechanism modulating the redox chemistry of hexaazatriphenylene-based small molecules by push-pull electron effect for zinc-ion batteries 认领 引用 被引量：1
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作者 Zhi-Qiang Wang Jing-Wei Liu +12 位作者 Jing-Jing Chen Yong-Cong Huang lftikhar Hussain Wen Luo Hui-Min Yuan Jing Hu Zhen-Yu Wang Ming-Yang Yang Ying-Zhi Li Gui-Yu Liu Shuai Gu Kai-Li Zhang Zhou-Guang Lu 《Rare Metals》 SCIE EI CAS CSCD 2025年第8期5345-5354,共10页
Organic compounds are promising electrode materials for aqueous zinc-ion batteries(AZIBs) but largely suffer from poor rate and cycling performance.This work reports that the push-pull electron effect of organic compo... Organic compounds are promising electrode materials for aqueous zinc-ion batteries(AZIBs) but largely suffer from poor rate and cycling performance.This work reports that the push-pull electron effect of organic compounds could be used to tune the electrochemical performance of AZIB s.Hexaazatriphenylene-based(HATN) small molecules with different withdrawing or donating groups were synthesized and used as electrodes for AZIBs.Compared to the hydrogen atoms and electrondonating methyl groups,the electron-withdrawing fluorine atoms endow HATN-based small molecule(HATN-6F)with a much-improved redox platform,rate performance and cycling stability.The fluorinated electrode HATN-6F potently amplifies and stabilizes the kinetics of cation co-(de)insertion reactions,concurrently enhancing the conductivity and electron affinity,resulting in improved rate performance and enhanced cycling stability.The combination of theoretical calculations and experimental characterization confirms that the fluorine-rich peripheral environment effectively modifies the distribution of conjugated electrons in HATN,enhancing its affinity for zinc ions and improving its capacity for cations zinc storage.This work demonstrates a new avenue for the design and synthesis of organic electrode with excellent electrochemical performance for ZIBs. 展开更多
关键词 Zinc-ion batteries Organicπ-conjugated molecules Fluorine-rich material Push-pull electron effect
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Synergistic effects of push-pull resonance molecules on passivation and charge dynamics in perovskite solar cells 认领 引用
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作者 Xiaozhen Huang Zilong Zhang +11 位作者 Yuheng Li Liangliang Zhang Can Wang Lusheng Liang Chi Li Chunming Liu Zhehong Zhou Ruidan Zhang Yue Wang Mingwei An Yang Wang Peng Gao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2025年第5期422-430,共9页
Exploring multifunctional interfacial modifiers is an effective approach to addressing interface issues in perovskite solar cells(PSCs)and improving device performance and stability.While most interfacial modifiers fo... Exploring multifunctional interfacial modifiers is an effective approach to addressing interface issues in perovskite solar cells(PSCs)and improving device performance and stability.While most interfacial modifiers focus on passivating defects at the interfaces,there has been limited investigation into the relationship between molecular design and interfacial charge dynamics.This work introduces resonance molecules with a push-pull effect for interfacial modification,allowing for synergistic regulation of passivation effects and charge dynamics.Specifically,FCz-PO,which includes an electron-withdrawing fluorine atom,exhibits superior passivation but poor molecular stacking and charge extraction.In contrast,MCz-PO,featuring an electron-donating methoxy group,provides effective passivation,wellordered molecular packing,and efficient charge extraction and transport.Consequently,PSCs using MCz-PO achieve high power conversion efficiency(PCE)of 24.74%and excellent operational stability.This study suggests that resonance structures can be an effective molecular design strategy for developing interfacial modifiers with both strong passivation capabilities and well-regulated charge dynamics. 展开更多
关键词 Push-pull effect Resonance molecule Interfacial modifiers Perovskite solar cells
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“Push-Pull”策略防治柑橘木虱研究现状 认领 引用 被引量：2
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作者 林文汉 王静 +2 位作者 周雨彤 桑文 邱宝利 《中国生物防治学报》 CSCD 北大核心 2025年第1期220-230,共11页
柑橘作为世界上重要经济作物之一,随着生产规模的扩大,病虫害日益成为制约其发展的瓶颈。在为害柑橘的众多害虫中,柑橘木虱Diaphorina citri Kuwayama为害最为严重,其成虫和若虫不仅能直接刺吸为害柑橘、柠檬等芸香科植物,还是传播柑橘... 柑橘作为世界上重要经济作物之一,随着生产规模的扩大,病虫害日益成为制约其发展的瓶颈。在为害柑橘的众多害虫中,柑橘木虱Diaphorina citri Kuwayama为害最为严重,其成虫和若虫不仅能直接刺吸为害柑橘、柠檬等芸香科植物,还是传播柑橘黄龙病(Huanglongbing,HLB)的重要媒介。“Push-Pull”策略作为害虫生态调控(Ecological regulation and management of pests,ERMP)中的一项重要技术,具有“经济、简便、有效、绿色”等优点。通过推广普及“Push-Pull”技术,将有助于控制柑橘木虱的为害,推动我国柑橘产业绿色发展。本文以综述“Push-Pull”策略为例,分别介绍了“Push”和“Pull”两个组分的研究进展,展望“Push-Pull”策略在防治柑橘木虱的发展应用,希望能为柑橘生产过程中经济、简便、有效地治理柑橘木虱提供理论参考和技术支撑,推动我国柑橘产业健康可持续发展。 展开更多
关键词 生态调控 柑橘木虱 “Push-Pull”策略 驱避 引诱
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Diverse roles of indacenodithiophene in push-pull chromophores for enhanced two-photon absorption and efficient nonlinear optical limiting 认领 引用
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作者 Yijia Chen Wendan Luo +3 位作者 Ke Liu Taihong Liu Liping Ding Yu Fang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2025年第10期29-36,共8页
Correlation between tunable optical properties and push-pull structural characters has attracted extensive attention in material science and nonlinear optics.Here,several indacenodithiophene(IDT)derivatives denoted as... Correlation between tunable optical properties and push-pull structural characters has attracted extensive attention in material science and nonlinear optics.Here,several indacenodithiophene(IDT)derivatives denoted as IDT-2NA,NA-IDT-CN,and IDT-2CN with different terminal substituents are investigated comparatively to demonstrate their intrinsic structure-property relationships.Interestingly,the IDT core acts diverse roles as acceptor(A)and donor(D)in the obtained three derivatives.Symmetric IDT-2NA with a D-A-D architecture shows an absorption maximum around 459 nm in THF.Contrary to the symmetric analog IDT-2CN with a reverse A-D-A feature,NA-IDT-CN with a different D-D'-A motif characterizes an obvious solvent polarity effect.Theo-retical calculation and electrostatic potential results confirm the terminal substituents with different electronic conjugation play vital roles in affecting the resultant photophysical properties.Utilizing the femtosecond open-aperture Z-scan technique,significant two-photon absorption(2PA)capabilities are obtained ranging from 540 to 900 nm.The 2PA cross section(δ2pA )maximum about 5390 GM of centrosymmetric IDT-2CN exhibits at 600 nm.Distinct excited-state dynamics with the help of femtosecond transition absorption supports the effective intramolecular charge transfer which accounts for enhancing theδ2pA values.Their potential optical power limiting applications based on the 2PA mechanism were further evaluated.The limiting thresholds were found to be 2.793.35 mJ/cm2 for the three IDT derivatives with a sequence of IDT-2CN<IDT-2NA<NA-IDT-CN.The distinct structural motifs and effective 2PA capabilities in the current work may provide reliable insights into the push-pull IDT chromophores for advanced nonlinear optical applications. 展开更多
关键词 Indacenodithiophene Push-pull effect Two-photon absorption Structure-property correlation Excited-state dynamics
Exploiting push-pull strategy to combat the tea green leafhopper based on volatiles of Lavandula angustifolia and Flemingia macrophylla 认领 引用 被引量：13
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作者 HAN Shan-jie WANG Meng-xin +3 位作者 WANG Yan-su WANG Yun-gang CUI Lin HAN Bao-yu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第1期193-203,共11页
Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, follo... Thirteen volatile compounds were identified from Flemingia macrophylla plants. Eight major components significantly attracted the tea green leafhoppers, Empoasca flavescens F. Based on their relative abundances, following synthetic blends were made for field experiments: 1) eight-component-attractant blend included Z-3-hexen-1-ol, Z-3-hexenyl acetate, Z-ocimene, Me SA, Z-3-hexenyl butyrate, dodecane, hexadecane and nonanal at 10, 10, 1, 11, 2, 6, 2 and 4 mg mL^-1 in n-hexane, respectively;2) four-component-attractant blend #1 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and nonanal at 2, 10, 10 and 4 mg mL^-1 in n-hexane, respectively;3) four-component-attractant blend #2 contained hexadecane, Z-3-hexenyl acetate, Z-3-hexen-1-ol and Me SA at 2, 10, 10 and 11 mg mL^-1 in n-hexane, respectively. Thymol and 1-methoxy-4-methyl-2-(1-methylethyl)-benzene, identified from Lavandula angustifolia aeration samples, significantly repelled the leafhopper as strong repellents when tested alone or in combination at 10 mg mL^-1. For field bioassays, each attractant lure was attached to a bud green sticky board hung from a bamboo stick at above tea plant level for catching the leafhoppers, whereas the repellent dispenser was tied to a tea branch inside tea clump for pushing the leafhoppers away from tea clumps. The results showed that the eight-component-attractant blend caught similar numbers of the leafhopper as did the four-component-attractant blend #1 at about 53–79 leafhoppersrap/day, which were significantly higher than those on the hexane-control bud green sticky boards. Average leafhopper catches from un-baited sticky boards were about 51–73 leafhoppersrap/day when pushed by the repellents placed inside tea plants, with the two-component-repellent blend being more effective than their single components. When the two-component-repellent blend was further tested with the three attractant blends in a push-pull fashion, average trap catches ranged from 62 to 92 leafhoppersrap/day. Control efficacy on the leafhoppers within the push-pull zones increased progressively from day 1(43%) to day 5(73%). This push-pull approach might have a great potential as a green control strategy for combating the tea green leafhoppers. 展开更多
关键词 push-pull strategy attractants repellents Flemingia macrophylla tea green leafhopper tea plantation
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Lappaconitine solid dispersion monolithic osmotic tablet and lappaconitine push-pull osmotic pump: preparation and comparison of their release performance in vitro 认领 引用 被引量：5
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作者 吴先闯 王姣姣 +4 位作者 郝海军 宋晓勇 张永州 刘瑜新 张红芹 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2017年第6期413-422,共10页
Lappaconitine is a water-insoluble drug, which was used as model drug in this study. Currently, two osmotically controlled delivery systems that are widely used for water-insoluble drug are monolithic osmotic tablet ... Lappaconitine is a water-insoluble drug, which was used as model drug in this study. Currently, two osmotically controlled delivery systems that are widely used for water-insoluble drug are monolithic osmotic tablet （MOT） and push-pull osmotic pump （PPOP）. In the present study, lappaconitine solid dispersion monolithic osmotic tablet （lappaconitine-SD-MOT） and lappaconitine-PPOP were developed. The prepared lappaconitine-PPOP was able to delivery drug at the rate of approximate zero-order （r = 0.9931）, and the cumulative release was above 95.0%. The lappaconitine-SD-MOT showed a comparatively poor linearity when the data were plotted according to the zero-order equation （r = 0.9798）, and the cumulative release was 84.69%. Lappaconitine-PPOP exhibited better controlled drug release （higher regression value） compared with lappaconitine-SD-MOT. The similarity index （f2） between lappaconitine-PPOP and lappaconitine-SD-MOT was 49.1 （〈50）. A clear difference of drug release characteristics between the lappaconitine-SD-MOT and lappaconitine-PPOP was revealed. It indicated that the drug release performance of lappaconitine-PPOP could gain favorable zero-order kinetics and higher cumulative release compared with lappaconitine-SD-MOT. Therefore, these results suggested that PPOP was still a very effective device for the delivery of poorly water-soluble drug with zero-order pattern. 展开更多
关键词 Lappaconitine Solid dispersion Monolithic osmotic tablet Push-pull osmotic pumps
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两种新的push-pull平衡的大数据量无线传感器网络数据分发算法 认领 引用 被引量：5
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作者 陶孜谨 龚正虎 卢泽新 《计算机研究与发展》 EI 北大核心 2008年第7期1115-1125,共11页
无线传感器网络中如何获得较低的通信代价同时在事件数据的push和pull之间实现更好的平衡是各种数据分发算法共同追求的目标.分析了目前已公认较好的两种典型的有结构和无结构的数据分发算法,指出了它们的优缺点.在此基础上,结合这两种... 无线传感器网络中如何获得较低的通信代价同时在事件数据的push和pull之间实现更好的平衡是各种数据分发算法共同追求的目标.分析了目前已公认较好的两种典型的有结构和无结构的数据分发算法,指出了它们的优缺点.在此基础上,结合这两种算法使用的push-pull策略,针对不同应用环境下的无线传感器网络的ALL型查询的特定需求,提出了两种基于有结构和无结构存储模式相结合的混合型数据分发算法,分别是Hybrid-Dcs-Cn1(HDC1)算法和Hybrid-Dcs-Cn2(HDC2)算法.分析表明这两种算法在保证push-pull之间平衡的前提下解决了已有算法存在的热点问题:存储拷贝数多和查询性能低,能更好地适应传感器网络的特点,是两种能量高效的数据分发算法. 展开更多
关键词 数据分发 push-pull平衡 热点 通信代价 负载均衡 无线传感器网络
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Electron push-pull effects induced performance promotion in covalent organic polymer thin films-based memristor for neuromorphic application 认领 引用 被引量：2
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作者 Panke Zhou Hong Yu +6 位作者 Mun Yin Chee Tao Zeng Tianli Jin Hongling Yu Shuo Wu Wen Siang Lew Xiong Chen 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第5期227-231,共5页
Covalent organic polymer(COP)thin film-based memristors have generated intensive research interest,but the studies are still in their infancy.Herein,by controlling the content of hydroxyl groups in the aldehyde monome... Covalent organic polymer(COP)thin film-based memristors have generated intensive research interest,but the studies are still in their infancy.Herein,by controlling the content of hydroxyl groups in the aldehyde monomer,Py-COP thin films with different electronic push-pull effects were fabricated bearing distinct memory performances,where the films were prepared by the solid-liquid interface method on the ITO substrates and further fabricated as memory devices with ITO/Py-COPs/Ag architectures.The Py-COP-1-based memory device only exhibited binary memory behavior with an ON/OFF ratio of 1:101.87.In contrast,the device based on Py-COP-2 demonstrated ternary memory behavior with an ON/OFF ratio of 1:100.6:103.1 and a ternary yield of 55%.The ternary memory mechanism of the ITO/Py-COP-2/Ag memory device is most likely due to the combination of the trapping of charge carriers and conductive filaments.Interestingly,the Py-COPs-based devices can successfully emulate the synaptic potentiation/depression behavior,clarifying the programmability of these devices in neuromorphic systems.These results suggest that the electronic properties of COPs can be precisely tuned at the molecular level,which provides a promising route for designing multi-level memory devices. 展开更多
关键词 Covalent organic polymers Push-pull effects Multi-level memory Memristor
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Influential Factors in Employment Location Selection Based on “Push-Pull” Migration Theory—A Case Study in Three Gorges Reservoir Area in China 认领 引用 被引量：13
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作者 XU Ding-de ZHANG Ji-fei +3 位作者 XIE Fang-ting LIU Shao-quan CAO Meng-tian LIU En-lai 《Journal of Mountain Science》 SCIE CSCD 2015年第6期1562-1581,共20页
In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull"... In China, farmers employed in non-farm work have become important socio-economic actors, but few studies have examined the farmers' perspective in making their work location choices. Based on "push-pull" migration theory, this paper utilizes sectional data from a 2013 survey of farmers in China's Three Gorges Reservoir area to empirically analyze the factors influencing migrant workers' choice of employment location. The results indicate that 60.46% of laborers have migrated from their home province, whereas 39.54% have remained in their home province. Focusing on personal, household, and community characteristics—in addition to the economic characteristics of the sample counties—multinomial logistic regression models reveal that farmer-laborers' employment location decisions are influenced by their personal capital endowment(age, years of education and social networks), family structure(the number of laborers, elders, children and students), home village characteristics(location, economic development level and the degree of relief of the land) and home county economic development level. Notably, male and female laborers' location decisions reveal a converging trend, and their differences are not pronounced. Per capita arable land area has little influence on location decisions, whereas the educational level of laborers has a significant impact. The results differ significantly from those found in previous studies. 展开更多
关键词 Off-farm employment Location selection Migrants Push-Pull migration theory Three Gorges Reservoir region China
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Push-Pull型不对称钴(III)咔咯的合成与性质 认领 引用 被引量：1
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作者 张振 温俊霞 +2 位作者 张生玉 朱卫华 梁旭 《合成化学》 CAS 北大核心 2020年第9期759-763,共5页
酸催化下,在水-甲醇体系中,合成并分离了3种含有Push-Pull取代基的新型低对称A2B型钴(III)咔咯,其结构经1H NMR,19F NMR和HR-MS(ESI-TOF)表征。并利用光谱学和电化学方法对3种钴咔咯的电子结构进行了深入研究。结果表明:引入Push-Pull... 酸催化下,在水-甲醇体系中,合成并分离了3种含有Push-Pull取代基的新型低对称A2B型钴(III)咔咯,其结构经1H NMR,19F NMR和HR-MS(ESI-TOF)表征。并利用光谱学和电化学方法对3种钴咔咯的电子结构进行了深入研究。结果表明:引入Push-Pull型不对称对钴(III)咔咯分子的电子结构有明显的调控作用,且随着引入基团的改变而产生显著的规律性差异,为进一步的分子设计、合成及其应用奠定基础。 展开更多
关键词 Push-Pull型咔咯 光谱性质 电化学性质 电子结构 合成
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Three-photon absorption in a push-pull type chromophore containing tricyanofuran acceptor 认领 引用
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作者 Yan Ji Ying Qian +2 位作者 Zhi Qiang Zhou Wei Lu Yi Ping Cui 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第7期757-760,共4页
Three-photon absorption（3PA） of a push-pull chromophore,2-（3-cyano-（3-（4-（dimethylamino）styryl）-5,5-dimethylcyclohex- 2-enylidene）methyl）-5,5-dimethylfuran-2-ylidene） malononitrile（CFM） including TCF grou... Three-photon absorption（3PA） of a push-pull chromophore,2-（3-cyano-（3-（4-（dimethylamino）styryl）-5,5-dimethylcyclohex- 2-enylidene）methyl）-5,5-dimethylfuran-2-ylidene） malononitrile（CFM） including TCF group was measured by the nonlinear transmission method using a femto-second Ti：Sapphire oscillator-amplifier laser system.Its three-photon absorption cross-sections at 1300 ran were 36.8×10^-79 cm^6 s^2 in the solution of DMF and 12.3×10^-79 cm^6 s^2 in the solution of CH_2Cl_2,respectively.The large values were got by experiments in this paper,which is a new exploration for these kinds of materials.The molecule has the potential application foreground of 3PA areas and optical power limiting. 展开更多
关键词 Three-photon absorption Optical power limiting Nonlinear transmission method Push-pull chromophore TCF
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Push-Pull型pFLASH开关单元结构设计及特性 认领 引用
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作者 刘国柱 洪根深 +5 位作者 于宗光 赵文彬 曹利超 吴素贞 李燕妃 李冰 《半导体技术》 CAS CSCD 北大核心 2018年第9期652-658,663,共7页
基于90 nm eFLASH工艺设计并制备了一种新型抗辐照Push-Pull型pFLASH开关单元,并对其特性进行了研究。该结构由2个2T-FLASH管（T1/T2）和1个信号传输PMOS管（T3）组成,采用带带隧穿（BTBT）编程方式和福勒-诺德海姆（FN）擦除方式实现... 基于90 nm eFLASH工艺设计并制备了一种新型抗辐照Push-Pull型pFLASH开关单元,并对其特性进行了研究。该结构由2个2T-FLASH管（T1/T2）和1个信号传输PMOS管（T3）组成,采用带带隧穿（BTBT）编程方式和福勒-诺德海姆（FN）擦除方式实现其＂开/关＂态功能。同时,对其＂开/关＂态特性进行表征,研究其耐久性和电荷保持特性,最后,对其抗总剂量（TID）能力进行评估。实验结果表明：该器件的＂T1编程-T2擦除＂与＂T1擦除-T2编程＂态均可以实现信号传输管的＂开/关＂态功能,其阈值窗口的均值约为10.5 V;在工作电压为-1.2 V条件下,T3管的＂开＂态驱动电流均值约为0.92 mA,＂关＂态漏电流低于40 pA,且均表现出了良好的一致性。同时,该器件的循环擦/写次数可达10 000次,在25℃的＂开/关＂态应力条件下寿命大于10年,抗总剂量能力可达150 krad（Si）以上。 展开更多
关键词 Push-Pull型pFLASH开关单元 “开/关”态 阈值窗口 电荷保持性 总剂量(TID)
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基于DTN网络的PUSH-PULL策略研究 认领 引用
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作者 崔永锋 《河南师范大学学报（自然科学版）》 CAS 北大核心 2010年第6期54-56,共3页
DTN网络是新一代的网络体系结构,PUSH-PULL是解决DTN网络中拥塞控制的一种有效策略,介绍了DTN网络中拥塞控制的研究现状,并对PUSH-PULL的各个策略进行了阐述,通过NS2搭建DTN网络环境并通过模拟对PUSH-PULL的7种策略进行仿真,模拟仿真结... DTN网络是新一代的网络体系结构,PUSH-PULL是解决DTN网络中拥塞控制的一种有效策略,介绍了DTN网络中拥塞控制的研究现状,并对PUSH-PULL的各个策略进行了阐述,通过NS2搭建DTN网络环境并通过模拟对PUSH-PULL的7种策略进行仿真,模拟仿真结果表明,采用PUSH-PULL策略的可以有效的提高信息的传输率. 展开更多
关键词 DTN PUSH-PULL NS2 仿真
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Comparison of the severity of injury of hippocampal neuron in rats induced by simulated push-pull maneuver at various degrees 认领 引用
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作者 Suhong Guo Hui Zhang 《Neural Regeneration Research》 CAS 2006年第1期10-13,共4页
BACKGROUND： Push-pull effect is often caused during maneuver, and the changes of unconsciousness induced can affect or damage cerebral neurons at various degrees. OBJECTIVE： To observe the effect of simulated push-p... BACKGROUND： Push-pull effect is often caused during maneuver, and the changes of unconsciousness induced can affect or damage cerebral neurons at various degrees. OBJECTIVE： To observe the effect of simulated push-pull maneuver at various degrees on injury of hippocampal neurons in rats and analyze its phase effect. DESIGN： Randomized control study.SETTING ： Physiological Department of Jilin Medical College.MATERIALS： A total of 40 healthy male Wistar rats, of clean grade, weighting 205-300 g, aged 3-4 months, were randomly divided into control group （n=4） and three push-pull experimental groups, including ＋2 Gz group （intensity： -2 Gz to ＋2 Gz, n=12）, ＋6 Gz group （-6 Gz to ＋6 Gz, n=12） and ＋8 Gz group （-8 Gz to ＋8 Gz, n=12）.METHODS： The experiment was completed in the Physiological Department of Jilin Military Medical College from March 2002 to May 2003. ① Rats in the experimental groups were put at the specially rolling arm of animal centrifugal machine. Then, they were pushed and pulled with ±2 Gz, ±6 Gz and ±8 Gz, respectively. The jolt was 1 Gz/s. However, rats in control group were not treated with any ways. ② Stroke index and neurological evaluation were performed on rats in the experimental groups at 0.5, 6 and 24 hours after push-pull. Stroke index was 25 points in total. The higher the scores were, the severer the cerebral injury was. Neurological evaluation was 10 points in total. The higher the scores were, the severer the nerve injury was. ③ Hippocampal tissue in brain of rats were selected to cut into sections at each time points, and form and distribution of neurons were observed in hippocampal areas with HE staining. Degrees of neuronal injury in hippocampal CA1 area were assayed after push-pull at various degrees with electron microscope. ④ Measurement data were compared with t test.MAIN OUTCOME MEASURES：① Stroke index and neurological evaluation; ② form and distribution of neurons in hippocampal areas;③ degrees of neuronal injury in hippocampal CA1 area.RESULTS： A total of 40 rats were involved in the final analysis. ① Stroke index and neurological evaluation of rats in experimental groups： At 30 minutes and 6 hours after push-pull exposure, stroke index and neurological evaluation were higher in ±6Gz group and ±8 Gz group than those in control group （P 〈 0.01）, especially at 6 hours after push-pull exposure, those in ±8 Gz group were the highest at each time points [（11.00±2.16）, （5.75±1.70） points]. At 24 hours after exposure, those were decreased as compared with those within the former two time points, but the values were still higher than those in control group （P 〈 0.05-0.01）. ② Results of HE staining： At 6 and 24 hours after exposure, partially neuronal degeneration was observed in pyramidal layer in ±6 Gz group and ±8 Gz group, including crenation of neurons, tdangle or polygon, and karyopycnosis, especially the injury in ±8 Gz group was the most obvious at 6 hours after exposure. ③ Results of ultrastructure with electron microscope： Partially neuronal degeneration at various degrees was observed in hippocampal CA1 area in ±2 Gz group at 6 hours after exposure and in ±6 Gz group and ±8 Gz group at 6 and 24 hours after exposure. At 6 hours after exposure, nucleus of hippocampal neurons in ±8 Gz group was irregular and umbilication. Caryotin was aggregated, nuclear matrix was swelled and disorder, and vacuolation was also observed. Rough endoplasmic reticulum was expanded, mitochondrium was swelled, and crista was disappeared.CONCLUSION： ① Push-pull cannot damage hippocampal neurons of rats in ±2 Gz group. ② Exposure can cause injury of hippocampal neurons of rats in ±6Gz group and ±8 Gz group, especially the injury is the severest at 6 hours after exposure in ±8 Gz group and relieves gradually 24 hours later. 展开更多
关键词 Comparison of the severity of injury of hippocampal neuron in rats induced by simulated push-pull maneuver at various degrees
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Synthesis and Electronic Structure of Triazasubporphyrin with Peripherally Low Symmetric Push-pull Substitutions 认领 引用
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作者 FAN Yu-Xuan YUAN Tai-Yan +3 位作者 LV Qing-Yang LI Min-Zhi ZHU Wei-Hua LIANG Xu 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2020年第1期36-40,2,共5页
Peripherally low symmetric substitution with electron-donating(EDG)and electron-withdrawing(EWG)substituents caused the rational modulation of geometric structure and even the electronic structure of triazasubporphyri... Peripherally low symmetric substitution with electron-donating(EDG)and electron-withdrawing(EWG)substituents caused the rational modulation of geometric structure and even the electronic structure of triazasubporphyrin,the smallest 14πconjugated aza-porphyrinoids.Both structural characterization and spectroscopic investigation were discussed to provide an in-depth understanding of the relationship between peripheral push-pull substituents and SubPz core. 展开更多
关键词 triazasubporphyrin push-pull effect electronic structure seterochemistry
Triphenylamine-based highly active two-photon absorbing chromophores with push-pull systems 认领 引用
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作者 Yanqi Ban Linhong Hao +3 位作者 Zhenbo Peng Lishui Sun Lihua Teng Yingjie Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2023年第7期444-448,共5页
Two triphenylamine-based star-type push-pull chromophores(T1, T2) were designed and synthesized.Triphenylamine serves as the central core and acts as an electron-donating group surrounded by electronwithdrawing pentaf... Two triphenylamine-based star-type push-pull chromophores(T1, T2) were designed and synthesized.Triphenylamine serves as the central core and acts as an electron-donating group surrounded by electronwithdrawing pentafluorobenzene or N,N-dimethyl substituted tetrafluorobenzene, which are connected by ethylene bridges. Single-crystal X-ray diffraction confirmed the structures and molecular arrangement of two chromophores. The systematic photophysical research of T1 and T2 absorption characteristics was carried out to gain a better understanding of how structure-property relationships affect the observed nonlinear optical absorption phenomenon. Complementary calculations based on density functional theory(DFT) further confirmed the experimental results. Both chromophores exhibited excellent two-photon absorption(TPA) properties in CH2Cl2. Notably, T2 has more remarkable nonlinear optical absorption effects with the TPA cross-section up to 4.24 × 10~7GM. By adjusting the electronic structures of the chromophores through introducing pentafluorobenzene or N,N-dimethyl as functional groups with different electron-donating or withdrawing behaviors, the TPA performance of the small organic molecule could be greatly enhanced. These molecular structures with push-pull systems were excellent candidates for different two-photon applications. 展开更多
关键词 Star-type chromophores Triphenylamine derivatives Two-photon absorption Nonlinear optical materials Push-pull systems
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高并发数据共享系统基于Push-Pull混合模式的性能优化 认领 引用
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作者 王子光 王子明 《现代信息科技》 2018年第4期65-67,共3页
随着面向服务架构的大规模分布式系统的应用,多个系统之间由于数据集成的需要,彼此间要高并发传递大量数据,特别是状态数据的同步,对数据的实时性要求越来越高。数据单纯通过客户端以Pull(拉取)模式获取已经不能满足实时性要求,高频率... 随着面向服务架构的大规模分布式系统的应用,多个系统之间由于数据集成的需要,彼此间要高并发传递大量数据,特别是状态数据的同步,对数据的实时性要求越来越高。数据单纯通过客户端以Pull(拉取)模式获取已经不能满足实时性要求,高频率服务调用也会给服务端数据库带来较大的压力。单纯通过服务端以Push(推送)模式推送给客户端也不能满足客户端对个性化数据的需求,大量推送既会给服务端带来较大压力,又会造成客户端数据处理不及时。本文针对高并发数据共享系统应用过程中产生的性能问题,提出一种基于pub/sub消息处理的Push-Pull混合模式优化方案,实践表明该方案极大地提高了系统可用性及数据安全性,对同类系统的性能优化具有较好的借鉴作用。 展开更多
关键词 高并发 数据共享系统 性能优化 pub/sub消息处理 Push-Pull混合模式
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Push-Pull Finite-Time Convergence Distributed Optimization Algorithm 认领 引用 被引量：1
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作者 Xiaobiao Chen Kaixin Yan +3 位作者 Yu Gao Xuefeng Xu Kang Yan Jing Wang 《American Journal of Computational Mathematics》 2020年第1期118-146,共29页
With the widespread application of distributed systems, many problems need to be solved urgently. How to design distributed optimization strategies has become a research hotspot. This article focuses on the solution r... With the widespread application of distributed systems, many problems need to be solved urgently. How to design distributed optimization strategies has become a research hotspot. This article focuses on the solution rate of the distributed convex optimization algorithm. Each agent in the network has its own convex cost function. We consider a gradient-based distributed method and use a push-pull gradient algorithm to minimize the total cost function. Inspired by the current multi-agent consensus cooperation protocol for distributed convex optimization algorithm, a distributed convex optimization algorithm with finite time convergence is proposed and studied. In the end, based on a fixed undirected distributed network topology, a fast convergent distributed cooperative learning method based on a linear parameterized neural network is proposed, which is different from the existing distributed convex optimization algorithms that can achieve exponential convergence. The algorithm can achieve finite-time convergence. The convergence of the algorithm can be guaranteed by the Lyapunov method. The corresponding simulation examples also show the effectiveness of the algorithm intuitively. Compared with other algorithms, this algorithm is competitive. 展开更多
关键词 Distributed Optimization Finite Time Convergence Linear Parameterized Neural Network Push-Pull Algorithm Undirected Graph
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Basic Study on Perfect Push-Pull Local Ventilation 认领 引用
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作者 Yukihiro Hattori Koichi Nakabayashi +1 位作者 Osami Kitoh Motoyuki Ito 《Journal of Energy and Power Engineering》 CAS 2012年第12期1940-1944,共5页
In this study, the authors experimentally investigated the changes of the mean velocity component profiles, half-widths （b12）, turbulence intensities, Reynolds shear stress and intermittency of turbulence of a trans... In this study, the authors experimentally investigated the changes of the mean velocity component profiles, half-widths （b12）, turbulence intensities, Reynolds shear stress and intermittency of turbulence of a transient plane turbulent jet developing from a jet exit into a hood opening. The values of maximum mean-velocity and half-widths of the axial velocity profile along the center-line of the jet are greater than those for a fully developed two-dimensional jet. Turbulence intensity in the axial direction is not affected by the flow rate ratio. At the same time, turbulence intensity in the lateral direction becomes greater as the hood is approached and the flow rate ratio Q3/Q1 becomes larger （QI is jet flow rate from nozzle and Q3 is suction flow rate produced by the hood）. These experimental results are in accord with the distributions of production terms in the axial and lateral directions. Reynolds shear stress becomes smaller as the flow rate ratio becomes larger near the hood. Dimensionless distance y1/br2, from the center axis of the flow to the point where intermittency factor y becomes a constant value, narrows as the flow rate ratio becomes larger near the hood. 展开更多
关键词 Turbulence intensity intermittency factor Reynolds shear stress push-pull ventilation.
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