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Analysis of blasting vibration signal of high steep anti-dip layered rock slope

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Journal of Mountain Science 2022年第11期19卷 3257-3269页

作者： SUN Xiao-ming PANG Shi-hui QIN Ke SHITing-ting ZHU Chun TAO Zhi-gang State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining&Technology(Beijing)Beijing 100083China School of Mechanics and Civil Engineering China University of Mining&Technology(Beijing)Beijing 100083China College of Earth Science and Engineering Hohai UniversityNanjing 210098China

Blasting is one of the most economical and efficient mining methods in open-pit mine production.However,behind the huge benefits,it poses a hidden threat to the quality of slope rock mass,stability of slope,and safety of nearby buildings.In order to explore the influence of blasting vibration on the stability of anti-dip layered rock slopes,herein,the site near the large-scale toppling failure area of Changshanhao gold mine stope of Inner Mongolia Taiping Mining Co.,Ltd.was selected for on-site blasting test and monitoring.The Peak Particle Velocity(ppv)measured at the monitoring point is located on the lower side of the maximum allowable vibration velocity curve that is prepared based on the allowable speed standard evaluation chart in the full frequency domain established by standards practiced in various countries such as German DIN4150,the USBM RI 8507,and Chinese GB6722-2014.This indicates that the blasting vibration has less influence on the location of the monitoring point.The vibration signals obtained in the blasting test were analyzed using the wavelet packet theory,and it was concluded that the blasting vibration signals measured in the anti-dip layered rock slope were mainly concentrated in two frequency bands of 0-80 Hz and 115-160 Hz.The sum of energy of the two frequency bands accounted for more than 99%,wherein,the energy contained in the 0-80 Hz frequency band accounted for more than 85%of the monitoring signals.The vibration signal with 0-80 Hz frequency band monitored at the slope toe was selected for the energy attenuation analysis.The results showed that the energy attenuation decreased in radial,vertical,and tangential directions.Further,the Energy Attenuation Rate per Meter(EARPM)was calculated.In conjunction with the site characteristics analysis,it was found that the energy attenuation rate was significantly affected by the rock mass characteristics of the structural plane.The slope reinforcement project can effectively reduce the absorption of vibration energy by the slope and increase s

关键词： Anti-dip rocky slope Blasting vibration ppv Wavelet packet theory EARPM

Genome-wide detection of additional fetal chromosomal abnormalities by cell-free DNA testing of 15,626 consecutive pregnant women

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Science China(Life Sciences) 2019年第2期62卷 215-224页

作者： Hong Yao Ya Gao Jia Zhao Rong Zhang Huixin Xu Huamei Hu Yanmei Luo Yuying Yuan Meili Fu Hongyun Zhang Hui Jiang Wei Wang Huanming Yang Jian Wang Zhiqing Liang Fang Chen Department of Gynecology & Obstetrics Southwest Hospital the Third Military Medical University BGI-Shenzhen China National GeneBank BGI-Shenzhen Birth Defect Screening Project Lab BGI-Shenzhen Clinical laboratories of BGI Health BGI-Shenzhen James D.Watson Institute of Genome Sciences Laboratory of Genomics and Molecular Biomedicine Department of Biology University of Copenhagen

Cell-free DNA(cfDNA) testing for common fetal trisomies(T21, T18, T13) is highly effective. However, the usefulness of cfDNA testing in detecting other chromosomal abnormalities is unclear. We evaluated the performance of cfDNA testing for genome-wide abnormalities, and analyzed the incremental yield by reporting extra abnormalities. We performed genome-wide cfDNA testing in 15,626 consecutive pregnancies prospectively enrolled in this study. cfDNA testing results were reported and counseling was given depending on the presence of extra chromosomal abnormalities. cfDNA testing identified 190 cases(1.2%)of chromosomal abnormalities including 100 common trisomies and 90 additional abnormalities. By expanding the cfDNA reporting range to genome-wide abnormalities, the false positive rate increased to 0.39%(Pppv) was reduced to 65.58%(P=0.42). However, the detection yield increased from 0.44% to 0.65%(P=0.014), and cfDNA testing detected 38.61%(39/101) additional abnormalities with no ultrasound and biochemical screening findings. cfDNA testing outperformed biochemical screening by showing 60 times higher true positive rate and fewer false negative results.Genome-wide cfDNA testing significantly increased the diagnostic yield by detecting extra abnormalities, especially those without diagnostic indications. Genome-wide cfDNA testing has fewer false positive and false negative results compared with biochemical screening.

关键词： cell-free DNA genome-wide chromosomal abnormalities sensitivity specificity ppv

Preparation of Ligand Free Au NPs/ppv Composites with High Stability and Photo-electric Response

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Chinese Journal of Polymer Science 2015年第2期33卷 215-223页

作者： Fei Zhai Hao-tong Wei Su-mei Zhan Gan Jin Bai Yang 孙海珠黄宗浩 College of Chemistry Northeast Normal University State Key Laboratory of Supramolecular Structure & Materials College of Chemistry Jilin University

A novel kind of ligand free aurum nanoparticles（Au NPs）/poly（p-phenylene-vinylene）（ppv） composites was prepared via a simple approach. Although there were no ligands coating on the surface of the Au NPs, the Au NPs/ppv precursor composite exhibited excellent stability that no obvious variance was found as long as 6 months at -4 ℃ in aqueous and alcohol mixed solutions. This was attributed to the strong interaction between Au NPs and ppv precursor, which was further strengthened after heat transformation. Fourier transform infrared（FTIR） and Raman spectra showed the interaction between benzene ring in ppv and Au NPs led to the part transformation of the sp2 hybrid orbital into the sp3 one during the composite formation. As a result, the photoluminescence（PL） life time of ppv in the composite was longer than that of pure ppv. The Au NPs/ppv composite exhibited good photo-electric response, indicating their potential application in the area of the photoelectric conversion devices.

关键词： Au Nanoparticle ppv Composite Photo-electric

The effect of modified layers on the performance of inverted ZnO nanorods/MEH-ppv solar cells

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Science China(Physics,Mechanics & Astronomy) 2011年第3期54卷 453-458页

作者： YAN Yue ZHAO SuLing XU Zheng WEI Gong WANG LiHui Institute of Optoelectronic Technology Beijing Jiaotong University Beijing 100044 China Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing 100044 China Department of Physics Chinese People’s Public Security University Beijing 100038 China

We fabricate inverted organic/inorganic hybrid solar cells based on vertically oriented ZnO nanorods and polymer MEH-ppv. The morphology of ZnO nanorods and ZnO nanorods/MEH-ppv hybrid structure is depicted by using scanning electron microscopy (SEM), X-ray diffraction (XRD), and atomic force microscope (AFM), respectively. It is observed that ZnO nanorods array grows primarily aligned along the perpendicular direction of the ITO substrate. The MEH-ppv molecule does not enter the interspace between ZnO nanorods completely according to SEM picture. It results in the small and bad contact area between ZnO nanorods and MEH-ppv. To improve the photovoltaic performance, we also fabricate another kind of photovoltaic (PV) device modified by N719 dye, and exploit the effect of N719. After the modification of ZnO nanorods by N719, not only Jsc increases from 0.257 mA/cm2 to 0.42 mA/cm2, but also Voc enhances from 0.37 V to 0.42 V. Insert LiF buffer layer between MEH-ppv and anode, Jsc of 1.05 mA/cm2 is obtained, and it is 2.5 times that the device without LiF.

关键词：氧化锌纳米棒太阳能电池光电性能 MEH ppv 改性层扫描电子显微镜原子力显微镜

Organic optoelectronics:materials,devices and applications

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光学精密工程 2005年第5期13卷 525-534页

作者： IAU Yi CUI Tian-hong Department of Mechanical Engineering University of Minnesota 111 Church Street SE Minneapolis MN 55455 USA

The interest in organic materials for optoelectronic devices has been growing rapidly in the last two decades. This growth has been propelled by the exciting advances in organic thin films for displays, low-cost electronic circuits, etc. An increasing number of products employing organic electronic devices have become commercialized, which has stimulated the age of organic optoelectronics. This paper reviews the recent progress in organic optoelectronic technology. First, organic light emitting electroluminescent materials are introduced. Next, the three kinds of most important organic optoelectronic devices are summarized, including light emitting diode, organic photovoltaic cell, and photodetectors. The various applications of these devices are also reviewed and discussed in detail. Finally, the market and future development of optoelectronic devices are also demonstrated.

关键词：光电子学 OLED ppv 显示器电路

Synthesis and electroluminescent properties of naphthalimide derivatives

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Chinese Journal of Chemistry 1999年第5期17卷 462-466,426页

作者：印寿根徐征黄文强张福强侯延冰王永生徐叙容 Institute of Optoelectronics Technology Northern Jiaotong University Beijing 100044 China Institute of Polymer Chemistry Nankai University Tianjin 300071 China

Naphthalimide derivatives, N-ethyl-4-acetylamino-l,8-naphthalimide (EAAN) and polymer with N-propyl-4-acetylamino-1,8-naphthalimide (PAAN) side-chain (P-PAAN) were successfully synthesized. Electroluminescent devices of ITO/PVK(120nm)/EAAN(50nm)/Al(150nm) (I) and ITO/PVK+ P-PhAN(10:1) (50nm)/Al( 150nm) (II) constructed with EAAN and P-PAAN as the emitting layer were investigated, whereas the single-layer devices of ITO/EAAN or P-PAAN(50nm)/Al(150nm) (III) were not observed to have any e-mission light. The emission results revealed that the exaction recombination formed by positive and negative charge carriers injected from electrodes of devices I and II was much more balanced than that of devices III, which implied that naphthalimide derivatives are a new type of electron-transporting materials with high performance. The electron-transporting properties of naphthalimide derivatives were also elucidated by investigation of the electroluminescent behaviors from both devices of ITO/ppv (80nm)/Al and ITO/ppv (80nm)/EAAN (20)nm)/Al hch fabricated with EAAN as the electron-transporting layer.

关键词： Electroluminescence naphthalimide derivatives ppv electron-transporting layer

Theoretical Study on One- and Two-Photon Absorption Properties of ppv Derivative with Electron-Donor Phenylanthracene as Pendent Group

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Chinese Journal of Chemistry 2007年第4期25卷 465-471页

作者：赵亮牟丽杨国春苏忠民秦春生邵琛 Institute of Functional Material Chemistry Faculty of Chemistry Northeast Normal University Changchun Jilin 130024 China College of Environment Ecosystem and Engineering Changchun University Changchun Jilin 130022 China

Based on the equilibrium structures from quantum mechanics AM1 method, employing INDO/CI method and the sum-over-state （SOS） formula, the one-photon absorption （OPA） and two-photon absorption （TPA） properties as well as the second hyperpolarizabilities were discussed in detail for a kind of ppv derivative poly 2-（9-phenylanthracen-10-yl）-1,4-phenylenevinylene （P1）. The results indicate that the two-photon cross section （3） increases with the increasing of the number of repeating segment （n）, however only a slight increase corresponds to the increasing of molecular weight when the repeating unit number arrives at a certain number. From this point of view, the TPA cross section values of P1 were extrapolated through the linear fit of 3 value vs. 1/n. The δ value of P1 is as high as 181 GM （1 GM=10^-50 cm^4·s·photon^-1）. Concerning the influence of pendent group and extension of π-conjugation on 3 values, another four oligomers P2, ppv, P1-1, and P2-1 were investigated for comparison. The calculation results reveal that the position and property of pendent group have great influence on the OPA and TPA properties. A most crucial role for relatively larger 3 value was played by the extension of π-conjugation.

关键词： one-photon absorption two-photon absorption cross section second hyperpolarizability ppv sum-over-state charge transfer

Synthesis and characterization of red-emission ppv copolymers containing fluorenone unit

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Journal of Central South University 2010年第2期17卷 269-276页

作者：邹应萍潘春跃张振华刘波贺跃辉周科朝周祎李永舫 School of Chemistry and Chemical Engineering Central South University State Key Laboratory of Powder Metallurgy Central South University Key Laboratory of Organic Solids Institute of ChemistryChinese Academy of Sciences

Two soluble copolymers of fluorenone and dioctoxylbenzene(PFN) or anthracene(PFNAn) were synthesized through Heck polymerization,and were characterized by gel permeation chromatography(GPC),FT-IR,1H-NMR,elemental analysis and thermogravimetric analysis.The polymers possess good solubility in common organic solvents and high thermal stability with the onset decomposition temperature at higher than 410 ℃.The photophysical properties of the polymers were investigated in both solutions and spin-coated films.Cyclic voltammetry results revealed that the copolymers possess higher electron affinity and reversible reduction/re-oxidation processes.Their electroluminescent properties were further investigated.PFN and PFNAn show stable and saturated red light emission with high thermal stability and high electron injection ability.This type of conjugated polymers may be promising for the applications as electron acceptors in polymer photovoltaic cells and electron transporting materials.

关键词：电子受体共聚物表征 ppv 共轭聚合物光发射电子单位排放

Retinal detachment repair through multifocal intraocular lens-overcoming visualization challenge of the peripheral retina

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International Journal of Ophthalmology(English edition) 2017年第6期10卷 1008-1010页

作者： Amir Hadayer Denis Jusufbegovic Shlomit Schaal Department of Ophthalmology and Visual Sciences University of Louisville

Sir Nicholas Harold Lloyd Ridley has revolutionized the practice of ophthalmology by performing the firstintraocular lens （IOL） implantation in 1949. His scientific achievement was acknowledged thirty years later, which led to US Food and Drug Administration approval in 1981. Although the basic principles of IOL implantation have not changed since, many efforts have been invested in perfecting IOL design during the past decades.

关键词： IOL Retinal detachment repair through multifocal intraocular lens-overcoming visualization challenge of the peripheral retina ppv