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Clicking ferrocene to halogenated boron-doped diamond surfaces
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作者 Mei Wang Sabine Szunerits +1 位作者 Rabah Boukherroub Mu-Sen Li 《Rare Metals》 SCIE EI CAS CSCD 2013年第1期100-104,共5页
The halogenated boron-doped diamond (BDD) surfaces were reacted with sodium azide through a nucle- ophilic substitution reaction. The resulting azide-terminated BDD surfaces were used to trigger the "click" reacti... The halogenated boron-doped diamond (BDD) surfaces were reacted with sodium azide through a nucle- ophilic substitution reaction. The resulting azide-terminated BDD surfaces were used to trigger the "click" reaction. Because of the attractive electrochemical properties of ferrocene-containing molecules, such as fast electron transfer rates, reversible redox activities, and favorable redox potentials, we show that ferrocene derivatives can be grafted onto non-oxidized diamond surfaces by "click chemistry". These redox-active ferrocene-containing layers on a BDD surface, because of their ability to store and release charges reversibly, have the potential to be used as hybrid molecular/semiconductor memory devices. 展开更多
关键词 HALOGENATED AZIDE Click chemistry FERROCENE
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正常成年人水平特异性CE-Chirp刺激声与Click刺激声诱发听性脑干反应的比较
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作者 程荷英 张运阁 《中华耳科学杂志》 CSCD 北大核心 2024年第4期622-626,共5页
目的研究正常成年人水平特异性CE-Chirp(level specific CE-Chirp,CE-Chirp LS)刺激声与Click刺激声诱发听性脑干反应(auditory brainstem response,ABR)反应阈与纯音听阈的关系及在不同声强下两种刺激声所诱发的ABR波形特点,探讨CE-Chi... 目的研究正常成年人水平特异性CE-Chirp(level specific CE-Chirp,CE-Chirp LS)刺激声与Click刺激声诱发听性脑干反应(auditory brainstem response,ABR)反应阈与纯音听阈的关系及在不同声强下两种刺激声所诱发的ABR波形特点,探讨CE-Chirp LS声诱发的ABR在听觉功能客观评估中的应用价值。方法选择正常成年人21例(共42耳)分别在0.5、1.0、2.0、4.0 kHz进行纯音气导听阈测试,获取其双耳各频率的纯音听阈,分别采用CEChirp LS刺激声与Click刺激声诱发ABR,测量2种刺激声在80、60、40 dB nHL的Ⅴ波波幅,获得2种刺激声下受试者的Ⅴ波反应阈,获取其在80 dB nHL刺激强度时Ⅰ、Ⅲ、Ⅴ波潜伏期。按照自身对照的方法对相同刺激强度下2种刺激声诱发的ABR潜伏期及波幅差异性进行统计分析,比较2种刺激声下Ⅴ波反应阈与纯音听阈差值。结果正常成年人80、60、40 dB nHL刺激强度下,CE-Chirp LS刺激声诱发的ABR的Ⅴ波波幅均大于Click刺激声,差异有统计学意义(P<0.001);CE-Chirp LS刺激声诱发的ABR的V波反应阈与纯音平均听阈差值均低于Click刺激声,差异有统计学意义(P<0.05);80 dB nHL声强下CE-Chirp LS刺激声Ⅰ波潜伏期长于Click刺激声,差异有统计学意义(P<0.001),CE-Chirp LS刺激声Ⅲ、Ⅴ波潜伏期与Click刺激声比较,差异无统计学意义(P>0.05)。结论正常成年人CE-Chirp LS刺激声与Click刺激声比较,无论在高强度还是低强度刺激下波幅均明显增大,Ⅴ波反应阈更接近于纯音听阈,更有利于纯音听阈判定,但潜伏期个体差异更大。 展开更多
关键词 CE-Chirp LS声 Click声 听性脑干反应 V波反应阈 波幅 潜伏期
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A facile strategy for tuning the density of surface-grafted biomolecules for melt extrusion-based additive manufacturing applications 被引量:1
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作者 I.A.O.Beeren G.Dos Santos +8 位作者 P.J.Dijkstra C.Mota J.Bauer H.Ferreira Rui L.Reis N.Neves S.Camarero-Espinosa M.B.Baker L.Moroni 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第3期277-291,共15页
Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsi... Melt extrusion-based additive manufacturing(ME-AM)is a promising technique to fabricate porous scaffolds for tissue engi-neering applications.However,most synthetic semicrystalline polymers do not possess the intrinsic biological activity required to control cell fate.Grafting of biomolecules on polymeric surfaces of AM scaffolds enhances the bioactivity of a construct;however,there are limited strategies available to control the surface density.Here,we report a strategy to tune the surface density of bioactive groups by blending a low molecular weight poly(ε-caprolactone)5k(PCL5k)containing orthogonally reactive azide groups with an unfunctionalized high molecular weight PCL75k at different ratios.Stable porous three-dimensional(3D)scaf-folds were then fabricated using a high weight percentage(75 wt.%)of the low molecular weight PCL 5k.As a proof-of-concept test,we prepared films of three different mass ratios of low and high molecular weight polymers with a thermopress and reacted with an alkynated fluorescent model compound on the surface,yielding a density of 201-561 pmol/cm^(2).Subsequently,a bone morphogenetic protein 2(BMP-2)-derived peptide was grafted onto the films comprising different blend compositions,and the effect of peptide surface density on the osteogenic differentiation of human mesenchymal stromal cells(hMSCs)was assessed.After two weeks of culturing in a basic medium,cells expressed higher levels of BMP receptor II(BMPRII)on films with the conjugated peptide.In addition,we found that alkaline phosphatase activity was only significantly enhanced on films contain-ing the highest peptide density(i.e.,561 pmol/cm^(2)),indicating the importance of the surface density.Taken together,these results emphasize that the density of surface peptides on cell differentiation must be considered at the cell-material interface.Moreover,we have presented a viable strategy for ME-AM community that desires to tune the bulk and surface functionality via blending of(modified)polymers.Furthermore,the use of alkyne-azide“click”chemistry enables spatial control over bioconjugation of many tissue-specific moieties,making this approach a versatile strategy for tissue engineering applications. 展开更多
关键词 Additive manufacturing BLENDING Surface functionalization Surface density Click chemistry HUMAN
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Secondary metabolites of mulberry leaves exert anti-lung cancer activity through regulating the PD-L1/PD-1 signaling pathway 被引量:1
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作者 Guiqin Ye Xin Sun +3 位作者 Jiuzhou Li Yuanyuan Mai Ruilan Gao Jianbin Zhang 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2024年第6期914-925,共12页
Lung cancer ranks the top of malignancies that cause cancer-related deaths worldwide.The leaves of Morus alba L are traditional Chinese medicine widely applied in respiratory diseases.Our previous work has demonstrate... Lung cancer ranks the top of malignancies that cause cancer-related deaths worldwide.The leaves of Morus alba L are traditional Chinese medicine widely applied in respiratory diseases.Our previous work has demonstrated the anti-lung cancer effect of secondary metabolites of mulberry leaf,but their mechanism of action has still not fully elucidated.We synthesized Moracin N(MAN)-Probe conjugated with alkyne to label lung cancer cells and identified protein targets by chemical proteomic analysis.MAN and its probe exerted similar growth-inhibitory effect on human lung cancer cells.Chemical proteomic results showed that MAN targeted the programmed death ligand 1(PD-L1)checkpoint pathway and T cell receptor(TCR)signaling pathway,indicating its immune-regulatory function.Cell-free surface plasmon resonance(SPR)results showed the direct interaction of MAN with PD-L1 protein.Molecular docking analysis demonstrated that MAN bound to E158 residue of PD-L1 protein.MAN downregulated the expression levels of PD-L1 in a time-and dose-dependent manner and disrupted the PD-L1/programmed death 1(PD-1)binding,including other secondary metabolites of mulberry leaves Guangsangon E(GSE)and Chalcomoracin(CMR).Human peripheral blood mononuclear cells(PBMCs)co-cultured with MAN-treated A549 cells,resulting in the increase of CD8^(+)GZMB^(+)T cells and the decrease of CD8^(+)PD-1^(+)T cells.It suggested that MAN exerts anti-cancer effect through blocking the PD-L1/PD-1 signaling.In vivo,MAN combined with anti-PD-1 antibody significantly inhibited lung cancer development and metastasis,indicating their synergistic effect.Taken together,secondary metabolites of mulberry leaves target the PD-L1/PD-1 signaling,enhance T cell-mediated immunity and inhibit the tumorigenesis of lung cancer.Their modulatory effect on tumor microenvironment makes them able to enhance the therapeutic efficacy of immune checkpoint inhibitors in lung cancer. 展开更多
关键词 Moracin N Click chemistry PD-L1 T cell Lung cancer
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“Click”运动高升力机制
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作者 夏震昊 唐斌 于紫江 《大连理工大学学报》 CAS CSCD 北大核心 2024年第1期9-20,共12页
研究了具有“Click”运动的模型翼在三维流场中的气动特性.采用计算流体力学方法求解三维非定常不可压缩Navier-Stokes方程,对比了简谐和“Click”运动所产生的升力与阻力,研究了升力最大时的前缘涡特性和展向流动.结果表明,在下拍过程... 研究了具有“Click”运动的模型翼在三维流场中的气动特性.采用计算流体力学方法求解三维非定常不可压缩Navier-Stokes方程,对比了简谐和“Click”运动所产生的升力与阻力,研究了升力最大时的前缘涡特性和展向流动.结果表明,在下拍过程的升力最大处,“Click”和简谐运动的前缘涡能够分别维持至翼展的80%和60%处.两种运动都会在翼展方向存在维持展向流动的压力梯度,而“Click”运动具有更显著的展向压力梯度,对展向涡度的能量输运效率更高,因此其前缘涡能够保持更完整的形态.在上拍过程中,两种运动的前缘涡形态差异不明显,“Click”运动快速上拍的运动特点使其能够快速地摆脱尾涡的干扰,从而维持升力. 展开更多
关键词 “Click”运动 计算流体力学 前缘涡 展向流动
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海豚不同个体间发声信号差异性分析
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作者 王一帆 袁世鹏 +1 位作者 张吉昌 刘滨 《海洋与渔业》 2024年第1期70-71,共2页
海豚在长期进化过程中形成了一套依靠声波进行通信、定位和环境识别的声纳系统。该声呐系统定位精度高、识别能力强,可以在能见度低的水下环境中快速发现和定位目标,其水下探测与识别效率远远超过人造设备。根据海豚声信号的用途不同,... 海豚在长期进化过程中形成了一套依靠声波进行通信、定位和环境识别的声纳系统。该声呐系统定位精度高、识别能力强,可以在能见度低的水下环境中快速发现和定位目标,其水下探测与识别效率远远超过人造设备。根据海豚声信号的用途不同,国际上通常将海豚的发声信号分为回声定位信号(Click)、通信交流信号(Whistle)、应急突发信号(Burst pulse)等。 展开更多
关键词 突发信号 声信号 交流信号 环境识别 声纳系统 水下环境 CLICK 声呐系统
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Development and Application of Detection Methods for Capture and Transcription Elongation Rate of Bacterial Nascent RNA
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作者 LI Yuan-Yuan WANG Yu-Ting +8 位作者 WU Zi-Chun LI Hao-Xuan FEI Ming-Yue SUN Dong-Chang GUALERZI O.Claudio FABBRETTI Attilio GIULIODORI Anna Maria MA Hong-Xia HE Cheng-Guang 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2024年第9期2249-2260,共12页
Objective Detection and quantification of RNA synthesis in cells is a widely used technique for monitoring cell viability,health,and metabolic rate.After exposure to environmental stimuli,both the internal reference g... Objective Detection and quantification of RNA synthesis in cells is a widely used technique for monitoring cell viability,health,and metabolic rate.After exposure to environmental stimuli,both the internal reference gene and target gene would be degraded.As a result,it is imperative to consider the accurate capture of nascent RNA and the detection of transcriptional levels of RNA following environmental stimulation.This study aims to create a Click Chemistry method that utilizes its property to capture nascent RNA from total RNA that was stimulated by the environment.Methods The new RNA was labeled with 5-ethyluridine(5-EU)instead of uracil,and the azido-biotin medium ligand was connected to the magnetic sphere using a combination of“Click Chemistry”and magnetic bead screening.Then the new RNA was captured and the transcription rate of 16S rRNA was detected by fluorescence molecular beacon(M.B.)and quantitative reverse transcription PCR(qRT-PCR).Results The bacterial nascent RNA captured by“Click Chemistry”screening can be used as a reverse transcription template to form cDNA.Combined with the fluorescent molecular beacon M.B.1,the synthesis rate of rRNA at 37℃is 1.2 times higher than that at 15℃.The 16S rRNA gene and cspI gene can be detected by fluorescent quantitative PCR,it was found that the measured relative gene expression changes were significantly enhanced at 25℃and 16℃when analyzed with nascent RNA rather than total RNA,enabling accurate detection of RNA transcription rates.Conclusion Compared to other article reported experimental methods that utilize screening magnetic columns,the technical scheme employed in this study is more suitable for bacteria,and the operation steps are simple and easy to implement,making it an effective RNA capture method for researchers. 展开更多
关键词 nascent RNA selection Click Chemistry fluorescence molecular beacon
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千禧一代和Z世代打开西藏的方式
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作者 Elsbeth van Paridon 《China's Tibet》 2024年第2期56-59,共4页
"Click,click,flash,flash.Click,flash,flash,flash,click,click,click.Flash,flash,flash.Gorgeous!Stunning!Absolutely fabulous!"With all the photos being taken around her,had this author not known any better,she... "Click,click,flash,flash.Click,flash,flash,flash,click,click,click.Flash,flash,flash.Gorgeous!Stunning!Absolutely fabulous!"With all the photos being taken around her,had this author not known any better,she would've thought to be in an episode of,well,Absolutely Fabulous,the illustrious 1990s British hit comedy documenting the wild misadventures of Edina"Eddy"Monsoon and her best friend Patsy Stone,who live in a virtually constant haze of inebriated self-interest. 展开更多
关键词 FLASH FLASH CLICK
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Retrospective Analysis of the Correlation between TMD, Headache and Bruxism
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作者 Audrey Morris Patricia Grabowski +1 位作者 Tanya Al Talib Neamat Hassan Abubakr 《Open Journal of Stomatology》 CAS 2023年第4期125-133,共9页
Aims: To evaluate the association between bruxism, headaches, and temporomandibular disorder (TMD). Methods: A keyword search of the clinical notes of patients’ charts in AxiUm<sup>TM</sup> was performed ... Aims: To evaluate the association between bruxism, headaches, and temporomandibular disorder (TMD). Methods: A keyword search of the clinical notes of patients’ charts in AxiUm<sup>TM</sup> was performed using the search terms “TMD”, “headache”, and “sleep bruxism” to identify these patients. The inclusion criteria were patients with partial of full dentition, aged 18 to 65 years old who attended the UNLV School of Dental Medicine clinics between January 2014 and September 2018. Patients with incomplete records and those who were completely edentulous formed the exclusion criteria. Data were analyzed using the Pearson Correlation Coefficient. Results: The final sample was made up of 529 patients. The highest percentage of study subjects were in the age range of 29 - 34 (17.9%), with a statistically significant correlation to pain on opening (P = 0.0403). Females showed a statistically significant correlation to TMJ clicking (P = 0.0033). Caucasians also had a statistically significant correlation to TMJ clicking (P = 0.0001). In addition, a statistically significant correlation between pain on opening or chewing and headaches was also observed (P = 0.0081). Conclusion: Within the limitations of the present study, Caucasians, and females presented with more TMJ clicking than the other study subjects. Young adults, in particular, experienced more pain on opening or chewing. 展开更多
关键词 TMD BRUXISM HEADACHES TMJ clicking Pain
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基于伪虎鲸click信号的主动声呐探测信号低截获性分析
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作者 张略 黄海宁 +1 位作者 尹力 薛山花 《声学技术》 CSCD 北大核心 2023年第2期156-160,共5页
为解决现代主动声呐易暴露的问题,提出以伪虎鲸click信号作为主动声呐发射信号波形进行探测,以实现声呐的低截获性。首先通过宽带模糊函数分析了伪虎鲸click信号的分辨性能;然后通过仿真对比单双基地声呐探测模型下,伪虎鲸click信号与... 为解决现代主动声呐易暴露的问题,提出以伪虎鲸click信号作为主动声呐发射信号波形进行探测,以实现声呐的低截获性。首先通过宽带模糊函数分析了伪虎鲸click信号的分辨性能;然后通过仿真对比单双基地声呐探测模型下,伪虎鲸click信号与常规主动声呐信号的截获因子,验证了其低截获性。结果表明,伪虎鲸click信号三维宽带模糊函数呈现理想的“图钉型”,时延分辨力达到7.644×10^(-6) s,频移分辨力达到7.405 Hz,具有良好的分辨性能;伪虎鲸click信号的截获因子在−4.887~−17.6 dB之间,始终小于0 dB,且远低于常规主动声呐信号,具有优异的低截获性能。伪虎鲸click信号作为声呐发射信号可实现有效与低截获性的声呐探测。 展开更多
关键词 伪虎鲸click信号 低截获性 宽带模糊函数 截获因子
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一种适用于被动声学监测系统的海豚回声定位信号快速检测方法 被引量:1
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作者 薛睿超 牛富强 《声学技术》 CSCD 北大核心 2023年第6期733-740,共8页
被动声学监测仪已成为海豚的声信号研究的重要手段。为解决监测系统计算速度慢、检测正确率低等问题,满足低功耗长期工作的需求,文章结合海豚回声定位信号的时域特征,提出了一种快速检测方法。该算法不需要进行快速傅里叶变换和频域分析... 被动声学监测仪已成为海豚的声信号研究的重要手段。为解决监测系统计算速度慢、检测正确率低等问题,满足低功耗长期工作的需求,文章结合海豚回声定位信号的时域特征,提出了一种快速检测方法。该算法不需要进行快速傅里叶变换和频域分析,因此大大提高了计算速度并有效降低了系统算力需求,进而延长被动声监测系统的工作时间和提高工作效率。使用野外和室内采集的中华白海豚以及宽吻海豚声信号数据进行测试。测试结果表明,检测速度大幅提高,且检测正确率达到90%以上。 展开更多
关键词 被动声学监测 快速检测 海豚回声定位信号 click信号特征
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Click chemistry-based enrichment strategy for tracing cellular fatty acid metabolism by LC-MS/MS
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作者 Ru-Jie Yang Jian Zou +2 位作者 Jia-Yue Liu Jiang-Kun Dai Jian-Bo Wan 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2023年第10期1221-1231,共11页
Fatty acids(FAs),which were initially recognized as energy sources and essential building blocks of biomembranes,serve as the precursors of important signaling molecules.Tracing FA metabolism is essential to understan... Fatty acids(FAs),which were initially recognized as energy sources and essential building blocks of biomembranes,serve as the precursors of important signaling molecules.Tracing FA metabolism is essential to understanding the biochemical activity and role of FAs in physiological and pathological events.Inspired by the advances in click chemistry for protein enrichment,we herein established a click chemistry-based enrichment(CCBE)strategy for tracing the cellular metabolism of eicosapentaenoic acid(EPA,20:5 n-3)in neural cells.Terminal alkyne-labeled EPA(EPAA)used as a surrogate was incubated with N2a,mouse neuroblastoma cells,and alkyne-labeled metabolites(ALMs)were selectively captured by an azide-modified resin via a Cu(I)-catalyzed azide-alkyne cycloaddition reaction for enrichment.After removing unlabeled metabolites,ALMs containing a triazole moiety were cleaved from solid-phase resins and subjected to liquid chromatography mass spectrometry(LC-MS)analysis.The proposed CCBE strategy is highly selective for capturing and enriching alkyne-labeled metabolites from the complicated matrices.In addition,this method can overcome current detection limits by enhancing MS sensitivity of targets,improving the chromatographic separation of sn-position glycerophospholipid regioisomers,facilitating structural characterization of ALMs by a specific MS/MS fragmentation signature,and providing versatile fluorescence detection of ALMs for cellular distribution.This CCBE strategy might be expanded to trace the metabolism of other FAs,small molecules,or drugs. 展开更多
关键词 Click chemistry-based enrichment EPA metabolism Terminal alkyne-labeled EPA Azide-modified resin LC-MS/MS
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Eutectic Solution Enables Powerful Click Reaction for In-Situ Construction of Advanced Gel Electrolytes
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作者 Weixin Ye Jirong Wang +1 位作者 Chi Zhang Zhigang Xue 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期258-264,共7页
Thiol-ene click reaction is an intriguing strategy for preparing polymer electrolytes due to its high activity,atom economy and less side reaction.However,the explosive reaction rate and the use of non-electrolytic am... Thiol-ene click reaction is an intriguing strategy for preparing polymer electrolytes due to its high activity,atom economy and less side reaction.However,the explosive reaction rate and the use of non-electrolytic amine catalyst hamper its application in in-situ batteries.Herein,a nitrogen-containing eutectic solution is designed as both the catalyst of the thiol-ene reaction and the plasticizer to in-situ synthesize the gel polymer electrolytes,realizing a mild in-situ gelation process and the preparation of high-performance gel electrolytes.The obtained gel polymer electrolytes exhibit a high ionic conductivity of 4×10^(−4)S cm^(−1)and lithium-ion transference number(t_(Li)^(+))of 0.51 at 60°C.The as-assembled Li/LiFePO_(4)(LFP)cell delivers a high initial discharge capacity of 155.9 mAh g^(-1),and a favorable cycling stability with the capacity retention of 82%after 800 cycles at 1 C is also obtained.In addition,this eutectic solution significantly improves the rate performance of the LFP cell with high specific capacity of 141.5 and 126.8 mAh g^(-1)at 5 C and 10 C,respectively,and the cell can steadily work at various charge–discharge rate for 200 cycles.This powerful and efficient strategy may provide a novel way for in-situ preparing gel polymer electrolytes with desirable comprehensive performances. 展开更多
关键词 eutectic solution in-situ gelation lithium metal battery polymer electrolyte thiol-ene click reaction
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圈养瓶鼻海豚对20 kHz连续声信号的行为响应研究 被引量:4
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作者 牛富强 许肖梅 +2 位作者 杨燕明 刘贞文 文洪涛 《声学学报》 EI CSCD 北大核心 2012年第6期595-600,共6页
将20 kHz连续声信号作为刺激信号,测试了厦门某海湾圈养的两只瓶鼻海豚对该信号的行为变化。通过对比信号发射期与间歇期海豚相对声源的水面距离、露出水面的次数以及水下发出的click定位声信号的数目等变化,判断发射信号对海豚行为的... 将20 kHz连续声信号作为刺激信号,测试了厦门某海湾圈养的两只瓶鼻海豚对该信号的行为变化。通过对比信号发射期与间歇期海豚相对声源的水面距离、露出水面的次数以及水下发出的click定位声信号的数目等变化,判断发射信号对海豚行为的影响。给出了瓶鼻海豚对测试信号产生躲避行为的声压级门限(154±2 dB re 1μPa,rms),并与鼠海豚的躲避声压门限级进行了对比。结果表明:信号发射期,瓶鼻海豚移离了声源位置,增加了露出水面的次数,水下发出click声信号的次数明显减少。因此,瓶鼻海豚对20kHz连续信号产生了行为改变。 展开更多
关键词 瓶鼻海豚 声信号 行为 圈养 CLICK 信号发射 信号产生 刺激信号
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听力异常儿童Chirp -ABR与click -ABR波V 阈值相关性研究 被引量:6
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作者 罗香林 李楚凌 +3 位作者 尹宝珠 戴桂林 王远明 徐亚雄 《听力学及言语疾病杂志》 CAS CSCD 北大核心 2015年第2期200-201,共2页
目的:研究听力异常儿童Chirp-ABR与click-ABR波V阈值的相关性,初步探讨Chirp-ABR应用于听力异常儿童听力检测的可行性。方法选择20例(40耳)3~36月龄听力异常儿童,先进行常规click -ABR检测,按click-ABR波V阈值分为轻度异常... 目的:研究听力异常儿童Chirp-ABR与click-ABR波V阈值的相关性,初步探讨Chirp-ABR应用于听力异常儿童听力检测的可行性。方法选择20例(40耳)3~36月龄听力异常儿童,先进行常规click -ABR检测,按click-ABR波V阈值分为轻度异常组、中度异常组、重度异常组及极重度异常组,再对各组儿童进行Chirp-ABR检测,将各组儿童Chirp-ABR波V阈值分别与click-ABR波V阈值进行相关性分析。结果轻度异常组、中度异常组、重度异常组及极重度异常组Chirp-ABR波V阈值与click-ABR波V阈值相关系数分别为0.94、0.83、0.72及0.56。结论 Chirp-ABR与click-ABR波V阈值相关性较好,但随着听力损伤程度的加重,相关性有所降低;Chirp-ABR可用于听力异常儿童的听力检测。 展开更多
关键词 听性脑干反应 Chirp刺激声 click声 反应阈
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厦门海域中华白海豚定位click信号特性 被引量:3
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作者 牛富强 杨燕明 +2 位作者 许肖梅 文洪涛 刘贞文 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2012年第5期951-954,共4页
对厦门海域中华白海豚的发声及信号特性进行研究,采用高频宽带数据记录系统获取了大量中华白海豚click信号,并利用Matlab软件和Excel 2007对这些信号进行时域和频域分析.结果表明:click信号通常以不同长度的序列形式出现,单个click信号... 对厦门海域中华白海豚的发声及信号特性进行研究,采用高频宽带数据记录系统获取了大量中华白海豚click信号,并利用Matlab软件和Excel 2007对这些信号进行时域和频域分析.结果表明:click信号通常以不同长度的序列形式出现,单个click信号长度分布在(33±4)μs;频谱能量分布广,低频至10kHz,高频达200kHz以上,具有单峰和双峰2种频谱结构,峰值频率、3dB带宽和10dB带宽分别为(113.3±16.3)、(48.3±14.2)和(113.3±16.4)kHz.中华白海豚click信号双峰的频率分布,为其在海底混响严重的浅海环境准确识别目标提供了保障. 展开更多
关键词 中华白海豚 定位click 频谱分析 信号特征
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α,ω–链端功能化聚烯烃的设计与合成新进展 被引量:6
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作者 姜涛 许芳 +1 位作者 董鹏 马志 《天津科技大学学报》 CAS 北大核心 2016年第3期1-10,共10页
链端功能化聚烯烃的设计与合成是近些年来的研究热点之一.合成α,ω–链端功能化聚烯烃的方法较多,活性聚合一般需要适当的金属催化剂,得到的聚合物相对分子质量分布窄,而且单体消耗完以后聚合物链仍保持活性,加入新的单体以后增长可以... 链端功能化聚烯烃的设计与合成是近些年来的研究热点之一.合成α,ω–链端功能化聚烯烃的方法较多,活性聚合一般需要适当的金属催化剂,得到的聚合物相对分子质量分布窄,而且单体消耗完以后聚合物链仍保持活性,加入新的单体以后增长可以继续进行,以此来制备嵌段共聚物,也可以加入终止剂终止聚合反应制备双端功能化聚烯烃.叶立德同源聚合通过引入带有不同功能基团的硼烷与叶立德进行反应,得到不同反应性基团封端的聚烯烃,再经过进一步的基团转化反应,可以得到多种不同的端基功能化的聚烯烃.此外,烯烃聚合过程中向链转移剂进行链转移反应、开环易位聚合以及与点击化学结合都可以用来制备链端功能化的聚烯烃.链端功能化聚烯烃不仅可以用作聚合物改性剂,而且更是构筑其他更复杂结构大分子的出发点,例如嵌段共聚物、接枝共聚物以及更为复杂的聚合物分子刷. 展开更多
关键词 聚烯烃 α ω–链端功能化 链转移反应 活性聚合 叶立德同源聚合 “Click”反应
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一种新型软件结构Click的研究与应用 被引量:5
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作者 张永德 王艳平 李秀艳 《计算机应用》 CSCD 北大核心 2003年第z1期40-41,共2页
Click是一种用于构建路由器的新型模块化软件结构。Click路由器由一些被称为element的数据包处理模块组成 ,具有配置灵活 ,易于扩展的特点。文中简要介绍了Click的结构和特点 ,并给出了一种在Click路由器中增加对 80 2 .1X协议支持的方法。
关键词 模块化结构 CLICK 路由器 802.1X协议
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听觉诱发电位仪的设计与实现方案 被引量:7
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作者 赵仕波 罗耀华 赵文华 《仪器仪表学报》 EI CAS CSCD 北大核心 2008年第3期594-599,共6页
本文介绍了听觉诱发电位仪的设计与实现方案,主要研究了听觉诱发电位仪原理以及硬件实现的总体方案,包括诱发电位仪的控制部分、波形发生部分、基准电压、噪声产生部分以及放大滤波部分的硬件电路,最后介绍了本系统的软件设计部分,并给... 本文介绍了听觉诱发电位仪的设计与实现方案,主要研究了听觉诱发电位仪原理以及硬件实现的总体方案,包括诱发电位仪的控制部分、波形发生部分、基准电压、噪声产生部分以及放大滤波部分的硬件电路,最后介绍了本系统的软件设计部分,并给出了相应的流程图。 展开更多
关键词 听觉诱发电位(AEP) 控制 CLICK声
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水性聚氨酯阻燃纳米复合材料的Click反应制备及性能 被引量:3
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作者 李兴建 鞠云鹏 +1 位作者 常德功 张宜恒 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2016年第8期1580-1588,共9页
以4,4'-二羟甲基-1,4-庚二炔功能单体作为扩链剂制备了端炔基功能化聚氨酯,与叠氮基改性纳米蒙脱土(MMT-N3)、纳米氢氧化铝(ATH-N3)和纳米氢氧化镁(MH-N3)通过Click反应制备了水性聚氨酯(WPU)阻燃纳米复合材料.采用红外光谱(FTIR)... 以4,4'-二羟甲基-1,4-庚二炔功能单体作为扩链剂制备了端炔基功能化聚氨酯,与叠氮基改性纳米蒙脱土(MMT-N3)、纳米氢氧化铝(ATH-N3)和纳米氢氧化镁(MH-N3)通过Click反应制备了水性聚氨酯(WPU)阻燃纳米复合材料.采用红外光谱(FTIR)、核磁氢谱(1H NMR)和扫描电子显微镜(SEM)对WPU阻燃纳米复合材料的结构进行了表征,对比研究了纳米阻燃剂配比和制备方法对WPU阻燃纳米复合材料的氧指数、动态燃烧行为和热稳定性的影响.阻燃性能研究结果表明,当MMT-N3,MH-N3和ATH-N3的质量分数分别为7%,2%和1%时,采用Click反应制备的复合材料的氧指数比纯WPU高7%,点燃时间从10 s延长到29 s,峰值热释放速率和烟释放速率分别降低了41%和42%.热失重分析结果表明,当MMT-N3质量分数为10%时,与WPU相比,采用Click反应制备的MMT/WPU复合材料在热失重50%时的温度提高了21℃.复合材料断面和燃烧后残渣的SEM分析证明在聚合物基体中Click反应是分散纳米材料的一种有效方法. 展开更多
关键词 阻燃水性聚氨酯 纳米蒙脱土 纳米氢氧化物 CLICK反应 动态燃烧行为
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