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Solvothermal Synthesis of a 3D Luminescent Cadmium-organic Framework with msw Topological Net

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Chinese Journal of Structural Chemistry 2013年第12期32卷 1890-1896页

作者： CUI pei-pei CUI Lun-Feng ZHANG Liang-Liang Key Lab of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong University Zhuli Middle School Hanting District College of Science China University of Petroleum (East China)

A new cadmium-organic framework, [Cd2（TBDC）2（DMF）2（H2O）]n （1）, was synthesized by solvothermal reaction of rigid carboxylate ligand 2,3,5,6-tetramethyl-l,4-ben- zenedicarboxylate （H2TBDC） and cadmium nitrate and characterized by elemental analysis, infrared spectrum, thermal analysis, PXRD, single-crystal X-ray diffraction and photoluminescence in the solid state. Compound 1 crystallizes in orthorhombic, space group Pca21 with a = 21.487（6）, b = 7.790（2）, c = 20.666（6） A, C30H40Cd2N2O11, Mr = 829.44, V= 3459.3（16） A3, Z = 4, Dc = 1.593 ***-3,μ = 1.29 mm-1, F（000） = 1672, 2.7〈θ〈27.2°, λ（MoKa） = 0.71073 A, T= 293（2） K, the final R = 0.026, wR = 0.0548 and S = 1.027. X-ray diffraction analysis reveals that complex 1 possesses a 3D framework and exhibits rnsw net. Thus, the solid-state luminescent spectrum of 1 displays that the emission of cadmium（lI） complex shows a peak at 317 nm upon 250 nm excitation at room temperature.

关键词： crystal structure Cd(II) complex hydrogen bond luminescenceproperties 2,3,5,6-tetramethyi-1,4-benzenedicarboxylate (H2TBDC)

Two 3-D multi-cascade co-design inverse methods based on streamline curvature approach and Clebsch formulation for single-stage centrifugal compressors

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航空动力学报 2013年第7期28卷 1526-1538页

作者： TIAN Xiao-pei SHAN Peng School of Energy and Power Engineering Beijing University of Aeronautics and Astronautics

Two strategies extended the single-cascade methods from a compressible three-dimensional inverse method for radial and mixed flow turbomachines to two three-dimensional multi-cascade co-design methods for single-stage centrifugal *** two three-dimensional methods and a typical quasi-threedimensional streamline curvature through-flow inverse method were employed to design the same subsonic high-speed single-stage centrifugal *** compressor performances were simulated by a commercial Reynolds averaged Navier-Stokes(RANS) equations *** studies show that two three-dimensional codesign methods are reasonable and *** was found that : firstly the blade camber angle designed by the three-dimensional methods was larger than that designed by the quasi-three-dimensional method;and secondly with regard to two three-dimensional methods with different boundary conditions,the co-design result differences between the diffusers were small,but those between the deswirlers were relatively large.

关键词： centrifugal compressor through-flow inverse method three-dimensional inverse problem streamline curvature approach Clebsch formulation multi-cascade co-design

基于地震勘探与瞬变电磁法信息融合的含水陷落柱精细探测研究

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煤矿现代化 2025年第1期34卷 78-83,90页

作者：裴建伟冯亮山西世德孙家沟煤矿有限公司山西忻州036600

在煤矿含水陷落柱精细探测中,地震波场与瞬变电磁场相结合的融合处理方法具有良好的发展前景。为此,以孙家沟煤矿为例,通过提取瞬变电磁法反演电阻率,优化8个对目标地质构造敏感的地震属性,选择基于粒子群优化(PSO-BPNN)的反向传播神经... 详细信息

在煤矿含水陷落柱精细探测中,地震波场与瞬变电磁场相结合的融合处理方法具有良好的发展前景。为此,以孙家沟煤矿为例,通过提取瞬变电磁法反演电阻率,优化8个对目标地质构造敏感的地震属性,选择基于粒子群优化(PSO-BPNN)的反向传播神经网络(BPNN)作为模型试验和工程应用的融合方法,通过试验模型验证了PSO-BPNN预测煤矿不同含水陷落柱(WBCC)的可行性和有效性,在工程应用中,将钻孔属性用于PSO-BPNN训练,取得了较好的融合效果。结果表明,8个属性可以作为基于地震法和瞬变电磁法的WBCC信息融合的主要特征集,进而通过PSO-BPNN检测煤矿陷落柱的边界和丰度。

关键词：地震属性瞬变电磁法含水陷落柱反向传播神经网络

Band gaps of elastic waves in 1-D phononic crystals with imperfect interfaces

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International Journal of Minerals,Metallurgy and Materials 2009年第5期16卷 608-614页

作者： Min Zheng pei-jun Wei School of Applied Science University of Science and Technology Beijing Beijing 100083 China

Band gaps of elastic waves in 1-D phononic crystals with imperfect interfaces were studied. By using the transfer matrix method （TMM） and the Bloch wave theory in the periodic structure, the dispersion equation was derived for the periodically lami- nated binary system with imperfect interfaces （the traction vector jumps or the displacement vector jumps）. The dispersion equation was solved numerically and wave band gaps were obtained in the Brillouin zone. Band gaps in the case of imperfect interfaces were compared with that in the case of perfect interfaces. The influence of imperfect interfaces on wave band gaps and some interesting phenomena were discussed.

关键词： phononic crystal transfer matrix band gap imperfect interface Bloch wave

Amides as surrogates of aldehydes for C–C bond formation:amide-based direct Knoevenagel-type condensation reaction and related reactions

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Science China Chemistry 2020年第1期63卷 11-15页

作者： Wei Ou pei-Qiang Huang Department of Chemistry Fujian Provincial Key Laboratory of Chemical Biology College of Chemistry and Chemical Engineering Xiamen University

Aldehydes are perhaps the most versatile compounds that enable many C-C bond forming reactions,which are not amenable for other subclasses of carbonyl *** report the first use of amides as surrogates of aldehydes for C-C bond formation,namely,the direct Knoevenagel-type condensation based on *** one-pot method consists of controlled reduction of an amide with LDBIPA[LiAlH(iBu)2(OiPr)],Lewis acid-mediated release of a reactive iminium ion intermediate,nucleophilic addition,and in situ elimination of *** reaction shows good functional group *** also demonstrated that the Schwartz reagent could be used as an alternative of *** employment of nitromethane and a silyl enol ether as the nucleophiles opens an avenue for the unprecedented amide-based nitro-aldol condensation reaction and aldol condensation reaction,respectively.

关键词： amides Knoevenagel condensation C–C bond formation one-pot reaction amide transformation

THE INTRUSION AND INFLUENCES OF INTRASEASONAL LONG ROSSBY WAVES IN THE EAST CHINA SEA

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Journal of Hydrodynamics 2004年第5期16卷 621-632页

作者： LINXiao-pei WUDe-xing LANJian InstituteofphysicalOceanographyandPhysicalOceanographyLaboratory OceanUniversityofChinaQingdao266003China

The analysis of sea level data from tide stations and ocean generalcirculation model (OGCM) shows that the intraseasonal long Rossby wave results in the intraseasonalvariations of Kuroshio axis and transport in the upper reaches of the Kuroshio in the East China Sea(ECS). Due to the transport modulation induced by Ryukyu Islands, the intraseasonal variation isvery weak in the lower reaches of the Kuroshio in the ECS. A two-layer model reveals the relationamong Kuroshio frontal unstable wave with topography, transport and the axis position of theKuroshio, from which we can infer that the intrusion of intraseasonal long Rossby wave may stimulatethe Kuroshio frontal unstable wave in the upper reaches of the Kuroshio in the ECS. The altimeterdata also shows that the sea level anomaly resulting from intraseasonal long Rossby wave could passthe channel between Taiwan and Ryukyu Islands and propagate northeastward in accord with theKuroshio frontal unstable wave. However, the sea level anomalies passing through the gaps of RyukyuIslands are relative weak and have negligible effects on the Kuroshio variation.

关键词： kuroshio intraseasonal long rossby wave unstable wave

Human herpesvirus 4 and adaptive immunity in Alzheimer’s disease

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Signal Transduction and Targeted Therapy 2020年第1期5卷 2077-2078页

作者： Jian-Sheng Kang pei-pei Liu Clinical Systems Biology Laboratories The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052 HenanChina

In a recent paper published in Nature,Gate et *** adaptive immune changes in Alzheimer’s disease(AD),discovered CD8+T effector memory CD45RA+(TEMRA)cells with proinflammatory and cytotoxic functions in AD patients,and identified two TEMRA cell-recognized antigens of human herpesvirus 4(HHV-4),also known as Epstein–Barr virus(EBV).1 The findings suggested that adaptive immunity might have a role in AD progression.

关键词： immunity CD45RA Alzheimer

Qinling Faunal Region-The Third Ordovician Faunal Region:International Correlation

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Acta Geologica Sinica(English Edition) 2000年第2期74卷 137-142页

作者： pei Fang Regional Geological Survey Party Henan Bureau of Geology and Mineral Exploration and DevelopmentPingdingshan 467021Henan

The Ordovician conodont faunal provinces were previously divided into the Midcontinent and Atlantic Faunal Regions situated respectively in low and high latitudes, where warm- and cold-water type conodont faunas flourished respectively. According to the international correlation this paper proposes the third Ordovician conodont faunal region—Qinling Faunal Region, in which cold-water conodont faunas were well developed in the Early to middle Middle Ordovician and warm-water conodont faunas were well developed in the late Middle and Late Ordovician, indicating that the Qinling Region was situated in high latitudes earlier and in low latitudes later. The origin was only due to plate movement. In the Qinling Region the time interval of the change of the conodont fauna from the cold- to warm-water type was 4 Ma (from 474 to 470 Ma), during which the fauna geographically spanned 40° of latitudes, with a movement velocity of nearly 1.12 m/a, indicating that the high-latitude plates were divorced and reduced in the late Middle Ordovician, while the low-latitude plates were converged and accreted. According to the features of the conodont faunas, the Qinling Faunal Region can be divided into the North Tarim, Wudang, Scandic and Pingliang provinces.

关键词： Midcontinent Faunal Region Altanic Faunal Region Qingling Faunal Region plate movement

Efficient Degradation of Cellulose in Its Homogeneously Aqueous Solution over 3D Metal-Organic Framework/Graphene Hydrogel Catalyst

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Chinese Journal of Chemical Physics 2016年第6期29卷 742-748,I0002页

作者： pei Huang Li-feng Yan DepartmentofChemicalPhysics iCHEMUniversityoFScienceandTechnologyofChinaHefei230026China

Catalytic degradation of cellulose to chemicals is an attracting topic today for the conver- sion of biomass, and the development of novel catalysts is a key point. Since metal-organic frameworks （MOFs） possess uniform, continuous, and permeable channels, they are valu- able candidate as catalysts. Here, a new 3D MOF/graphene catalyst was prepared by in situ growth of the zeolitic imidazolate frameworks （ZIF-8） nanoparticles inside the pore of an as-formed 3D reduced graphene oxide （rGO） hydrogel. The ZIF-8/rGO nanocomposite owns both micropores and mesopores with large specific surface area and plenty of acids sites, which is an idea catalyst for biomass degradation. Cellulose was dissolved in allmline aqueous solution at first, and then it was degraded efficiently over the new catalyst under hydrothermal condition. The conversion reaches 100% while the main products are formic acid with a maximum yield of 93.66%. In addition, the catalyst can be reused with high activity.

关键词： Graphene Metal-Organic framework Cellulose Catalyst Formic acid