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Pt-Sn clusters anchored at Al_(penta)^(3+) sites as a sinter-resistant and regenerable catalyst for propane dehydrogenation

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Journal of Energy Chemistry 2022年第2期31卷 293-301页

作者： Xinyue zhu Tinghai Wang Zhikang Xu Yuanyuan yue Minggui Lin Haibo zhu National Engineering Research Center of Chemical Fertilizer Catalyst School of Chemical EngineeringFuzhou UniversityFuzhou 350002FujianChina State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001ShanxiChina

Pt-based catalysts are widely used in propane dehydrogenation reaction for the production of *** irreversible deactivation caused by the sintering of Pt particles under harsh conditions and regeneration process is a significant challenge in this ***,a series of highly ordered mesoporous Al_(2)O_(3) supports with different levels of Al3+penta sites,are fabricated and used as the support to disperse Pt-Sn_(2) *** of Pt-Sn_(2)/meso-Al_(2)O_(3) with XRD,NMR,CO-IR,STEM,TG,and Raman techniques along with propane dehydrogenation-regeneration cycles test reveal the structure-stability-re generability *** coordinatively unsaturated pentacoordinate Al_(Al3+penta)^(3+)can strongly anchor Pt atoms via a formation of Al-O-Pt bond,and thus stabilize the Pt-based particles at the surface of Al_(2)O_(3).The stability and regenerability of Pt-Sn2/meso-Al_(2)O_(3) are strongly dependent on the content of Al3+penta sites in the Al_(2)O_(3) structure,and a high level of Al3+penta sites can effectively prevent the agglomeration of Pt-Sn2 clusters into large Pt nanoparticles in the consecutive dehydrogenation-regeneration *** Pt-Sn2/meso-Al_(2)O_(3)-600 with the highest level of Al_(penta)^(3+) (50.8%)delivers the best performance in propane dehydrogenation,which exhibits propane conversion of 40%and propylene selectivity above 98%at 570℃ with 10 vol%C_(3)H_(8) and 10 vol% H_(2) feed.A slow deactivation in this catalyst is ascribed to the formation of coke,and the catalytic performance can be fully restored in the consecutive dehydrogenation-regeneration cycles via a simple calcination treatment.

关键词： Propane dehydrogenation Pt catalyst Regeneration Sinter-resistance

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A robust watermarking algorithm based on QR factorization and DCT using quantization index modulation technique

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第8期13卷 573-584页

作者： Hong-yuan CHEN yue-sheng zhu Communication and Information Security Lab Shenzhen Graduate SchoolPeking UniversityShenzhen 518055China

We propose a robust digital watermarking algorithm for copyright protection.A stable feature is obtained by utilizing QR factorization and discrete cosine transform(DCT) techniques,and a meaningful watermark image is embedded into an image by modifying the stable feature with a quantization index modulation(QIM) *** combination of QR factorization,DCT,and QIM techniques guarantees the robustness of the ***,an embedding location selection method is exploited to select blocks with small modifications as the embedding *** can minimize the embedding distortion and greatly improve the imperceptibility of our *** standard images were tested and the experimental results were compared with those of other published *** results demonstrate that our proposed scheme can achieve not only better imperceptibility,but also stronger robustness against common signal processing operations and lossy compressions,such as filtering,noise addition,scaling,sharpening,rotation,cropping,and JPEG/JPEG2000 compression.

关键词： Digital watermarking QR factorization Quantization index modulation (QIM) Discrete cosine transform (DCT)

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A sharp gradient estimate for the weighted p-Laplacian

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Applied Mathematics(A Journal of Chinese Universities) 2012年第4期27卷 462-474页

作者： WANG Lin-feng zhu yue-ping School of Science Nantong UniversityNantong 226007China

Let M be an n-dimensional complete noncompact Riemannian manifold with sectional curvature bounded from below, dμ = e^h（x） dV（x） the weighted measure and △μ,p the weighted p-Laplacian. In this paper we consider the non-linear elliptic equation △μ,pu=-λμ,p｜u｜^p-2ufor p ∈ （1, 2）. We derive a sharp gradient estimate for positive smooth solutions of this equation. As applications, we get a Harnack inequality and a Liouville type theorem..

关键词： weighted p-Laplacian gradient estimate Harnack inequality Liouville theorem.

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Novel Method for Selective Debenzylation Under Maintenance of Fluoro Atom Substituted on β-Amino Acids

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Chemical Research in Chinese Universities 2011年第2期27卷 224-227页

作者： ZHENG Yi WU Gang zhu Xin-rong LI yue-jie MA Yu-heng ZHAO Xin LU Tao zhu yong-qiang School of Basic Sciences China Pharmaceutical University Nanjing 210009 P R. China Jiangsu Key Laboratory of Molecular Targeted Antitumor Drug Research Jiangsu Simcere Pharmaceutical Research Institute Nanjing 210042 P R. China

tert-Butyl （R）-3-amino-3-（3-fluorophenyl）propanoate（5） was prepared with conventional debenzylation method. However, the tert-butyl （R）-3-[（S）-1-phenylethyl-amino]-3-（3-fluorophenyl） propanoate（6） and tert-butyl （R）-3-amino-3-phenylpropanoate（7） were generated as the byproducts under the general catalytic hydrogenation Pd（OH）2/C-H2 conditions. So a series of experiments was performed to optimize the reaction conditions so that product 5 could be obtained with high purity and yield. Finally an effective catalytic system, Pd/C-HCOOH-CH3OH, was discovered.

关键词： β-Amino acid Debenzylation Defluorination Catalytic hydrogenation

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Partial Collapsing Degeneration of Floer Trajectories and Adiabatic Gluing

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Acta Mathematica Sinica,English Series 2024年第1期40卷 161-249页

作者： yong-Geun OH Ke zhu Center for Geometry and Physics Institute for Basic Science(IBS)79 Jigok-ro 127beon-gilNam-guPohang-siGyeongsangbuk-doKorea 37673&POSTECHGyeongsangbuk doKorea Department of Mathematics and Statistics Minnesota State UniversityMankatoMN 56001USA

In the present paper,we study partial collapsing degeneration of Hamiltonian-perturbed Floer trajectories for an adiabatic ε-family and its reversal adiabatic gluing,as the prototype of the partial collapsing degeneration of 2-dimensional(perturbed)J-holomorphic maps to 1-dimensional gradient *** consider the case when the Floer equations are S^(1)-invariant on parts of their domains whose adiabatic limit has positive length as ε→0,which we call thimble-flow-thimble *** main gluing theorem we prove also applies to the case with Lagrangian boundaries such as in the problem of recovering holomorphic disks out of pearly *** particular,our gluing theorem gives rise to a new direct proof of the chain isomorphism property between the Morse-Bott version of Lagrangian intersection Floer complex of L by Fukaya-Oh-Ohta-Ono and the pearly complex of L Lalonde and *** also provides another proof of the present authors’earlier proof of the isomorphism property of the PSS map without involving the target rescaling and the scale-dependent gluing.

关键词： Floer trajectory equation partial collapsing degeneration thimble-flow-thimble moduli space adiabatic gluing exponential decay estimates three-interval method

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Dynamic programming methodology for multi-criteria group decision-making under ordinal preferences

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Journal of Systems Engineering and Electronics 2010年第6期21卷 975-980页

作者： Wu Li Guanqi Guo Chaoyuan yue yong Zhao School of Information and Communication Engineering Hunan Institute of Science and Technology Yueyang 414006 E R. China Institute of Systems Engineering Huazhong University of Science and Technology Wuhan 430074 P. R. China

A method of minimizing rankings inconsistency is proposed for a decision-making problem with rankings of alternatives given by multiple decision makers according to multiple criteria. For each criteria, at first, the total inconsistency between the rankings of all alternatives for the group and the ones for every decision maker is defined after the decision maker weights in respect to the criteria are considered. Similarly, the total inconsistency between their final rankings for the group and the ones under every criteria is determined after the criteria weights are taken into account. Then two nonlinear integer programming models minimizing respectively the two total inconsistencies above are developed and then transformed to two dynamic programming models to obtain separately the rankings of all alternatives for the group with respect to each criteria and their final rankings. A supplier selection case illustrated the proposed method, and some discussions on the results verified its effectiveness. This work develops a new measurement of ordinal preferences’ inconsistency in multi-criteria group decision-making （MCGDM） and extends the cook-seiford social selection function to MCGDM considering weights of criteria and decision makers and can obtain unique ranking result.

关键词： multi-criteria group decision-making (MCGDM) ordinal preference minimum deviation method dynamic programming Cook-Seiford social selection function.

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A search for Mg-poor stars using LAMOST survey data

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Research in Astronomy and Astrophysics 2015年第8期15卷 1275-1281页

作者： Qian-Fan Xing Gang Zhao yong Zhang yong-Hui Hou yue-Fei Wang yue Wu Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of Sciences University of Chinese Academy of Sciences Nanjing Institute of Astronomical Optics & Technology National Astronomical ObservatoriesChinese Academy of Sciences

Most Galactic metal-poor stars exhibit enhanced α-abundances（e.g.[Mg/Fe] ～＋0.4） according to previous studies of stellar chemical ***, a handful of metal-poor stars with large deficiencies in Mg（e.g. [Mg/Fe]～-0.2） show severe departures from this α-enhancement trend. The sub-solar[Mg/Fe] ratios of these anomalous stars indicate that they possess different chemical enrichment histories than the majority of Galactic metal-poor stars. In previous work,we presented a method to select Mg-poor metal-poor stars from low-resolution SDSS spectra based on a spectral matching technique. In this paper, a similar method is applied to low-resolution（R ～ 1800） LAMOST spectra. Stellar [Mg/Fe] abundances are determined by using stellar parameters delivered by the LAMOST Data Release2 catalog. From a sample of ～ 60 000 stars with atmospheric parameters in the range Teff = [5500, 6500] K and [Fe/H] = [-2.4, ＋0.5], we select 15 candidate Mg-poor metal-poor stars.

关键词： methods: data analysis—stars: abundance—stars: atmospheres

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Probing dark matter spikes via gravitational waves of extreme-mass-ratio inspirals

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Science China(Physics,Mechanics & Astronomy) 2022年第10期65卷 45-52页

作者： Gen-Liang Li yong Tang yue-Liang Wu University of Chinese Academy of Sciences(UCAS) Beijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Center for Theoretical Physics Asia-Pacific(ICTP-AP UNESCO)UCASBeijing 100190China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China

The exact properties of dark matter remain largely unknown despite the accumulating evidence. If dark matter is composed of weakly interacting massive particles, it would be accreted by the black hole in the galactic center and form a dense, cuspy *** friction from this spike may have observable effects in a binary system. We consider extreme-mass-ratio inspiral(EMRI) binaries comprising massive black holes harbored in dark matter spikes and stellar mass objects in elliptic orbits. We find that the gravitational-wave waveforms in the frequency domain can be substantially modified. In particular, we show that dark matter can suppress the characteristic strain of a gravitational wave at low frequency but enhance it at a higher *** effects are more dramatic as the dark matter density increases. The results indicate that the signal-to-noise ratio of EMRIs can be strongly reduced near 10^(-3)-0.3 Hz but enhanced near 1.0 Hz with a higher sensitivity, which can be probed via the future space-borne gravitational-wave(GW) detectors, LISA and TAIJI. The findings will have important impacts on the detection and parameter inference of EMRIs.

关键词： dark matter gravitational wave black hole

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Optical coatings for fiber lasers

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光学精密工程 2005年第4期13卷 480-482页

作者： HONG Dong-mei zhu Zhen yue Wei North China Research Institute of Electro-optics BeiJing 100015 China

Fiber laser is the future development direction for the high energy lasers. This paper describs two kinds of optical coatings for fiber laser, including long and short wave pass filters. The one characteristic of fiber laser coatings lies in that coatings should separate two closely wavelength light including laser pump wavelength (980 nm) and laser irradiation wavelength(1 050～1 100 nm). At the same time, the coatings should have high laser damage threshold.

关键词：光纤激光器光学涂覆技术结构设计波长

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Synthesis and dehydrogenation properties of NaZn(BH4)3·en and NaZn(BH4)3·2en(en= ethylene diamine)

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Journal of Energy Chemistry 2020年第3期29卷 233-236页

作者： yong Wu yue Qi Jie Zheng Xingguo Li Beijing National Laboratory for Molecular Sciences(BNLMS) College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Two new hydrogen storage compounds,Na Zn(BH4)3·en and Na Zn(BH4)3·2en(en=ethylene diamine)are synthesized by a solution *** can release 6.4 wt%and 6.3 wt%pure hydrogen below 200℃,respectively,demonstrating the potential to be used as hydrogen ***,their dehydrogenation products,thermodynamics and kinetics are well characterized and *** shows that the stronger Zn-N interactions and the Hδ+–Hδ-interactions are significant for their stability below 100℃,relatively low decomposition temperatures and elimination of gas impurities.

关键词： Borohydride Ethylene diamine Hydrogen storage

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