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EXPlORATION　ON　ThE　BASIC　ACTIVE　CENTRES　OF　KF/Al_2O_3:EFFECTOF　PRETREATMENT　TEMPERATURE

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Chinese Chemical letters 1995年第9期6卷 811-814页

作者： zhu, Jh Tsuji, h Kabashima, h hattori, h Kita, h Nanjing Univ Dept Chem Nanjing 210093 Peoples R China hokkaido Univ Grad Sch Environm Earth Sci Div Sci Mat Sapporo Hokkaido 060 Japan hokkaido Univ Ctr Adv Res Energy Technol Sapporo Hokkaido 060 Japan

Abstract: KF/Al2O3 reached maxinmun activity at the pretreatment temperature(Tp) of 623K or 723K in Ibuters isomerization at 273K. according to the amount of KF loaded. Further increment of Tp lowered the activity of KF/Al2O3 due the suppression of [Al-OhF]strong basic sites through dehydroxylation. Changes in the state and function ofF caused the deactivation of KF/Al2O3 at high Tp.

关键词： KF/Al2O3 PRETREATMENT ThE CENTRES BASIC ACTIVE Al

A hOMOTOPY METhOD OF SWITChING SOlUTION BRANChES AT ThE PITChFORK BIFURCATION POINT

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Journal of Computational Mathematics 2001年第3期19卷 299-308页

作者： Cong, Y.-h. zhu, Z.-Y. College of Mathematical Sciences Shanghai Teachers University Shanghai 200234 China

Provides information on a study which proposed a continuation method for switching solution branches at a pitchfork point. Problem of the standard pitchfork; Information on the systems of equations; Numerical examples... 详细信息

关键词： homotopy method switching solution branches pitchfork point

Reliability of quasi integrable and non-resonant hamiltonian systems under fractional Gaussian noise excitation

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Acta Mechanica Sinica 2020年第4期36卷 902-909页

作者： Q.F.lu W.Q.zhu M.l.Deng Department of Mechanics State-Key Laboratory of Fluid Power and Mechatronic SystemsZhejiang UniversityHangzhou 310027China

The reliability of quasi integrable and non-resonant hamiltonian system under fractional Gaussian noise(fGn)excitation is *** rather flat fGn power spectral density(PSD)in most part of frequency band,the fGn is innovatively regarded as a wide-band ***,the stochastic averaging method for quasi integrable hamiltonian systems under wide-band noise excitation is applied to reduce 2n-dimensional original system into n-dimensional averaged ltd stochastic differential equations(SDEs).Reliability function and mean first passage time are obtained by solving the associated backward Kolmogorov equation and Pontryagin *** validity of the proposed procedure is tested by applying it to an example and comparing the numerical results with those from Monte Carlo simulation.

关键词： Reliability Fkst passage time Quasi integrable and non-resonant hamiltonian systems Fractional Gauss noise

Suppression of methane/air explosion by water mist with potassium halide additives driven by CO2

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维普期刊数据库

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Chinese Journal of Chemical Engineering 2019年第11期27卷 2742-2748页

作者： Wei Tan Dong lü liyan liu Guorui zhu Nan Jiang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300354China Tianjin Fire Research Institute of MEM Tianjin 300381China

To enhance the explosion suppression effects of water mist, various potassium halide additives were tested in a confined vessel filled with a 10% mixture of methane/air. Air and CO2(0.7 MPa) were used as driver gases. The results revealed that halide additives exhibit considerable suppression effects on explosion overpressure. A30% KI mist decreased the explosion overpressure by 27.46% compared with the suppression by pure water mist under the same conditions. When CO2 is used as the driver gas, it will dissolve in water under high *** synergistic effect of a CO2 solution with an effective additive afforded significant suppression. Under the same conditions, the overpressures suppressed by a mist of 30% KI + 0.7 MPa CO2 solution decreased by 33.53% compared with those suppressed by pure water mist driven by air. The synergistic suppression effect is much better than that of a 0.7 MPa CO2 solution mist or 30% KI mist alone. The multicomponent additives can be considered when suppressing methane/air explosions with pressure-formed water mist.

关键词： Methane Explosion suppression Water mist halide CO2

Comparison of continuous homogenous azeotropic and pressure-swing distillation for a minimum azeotropic system ethyl acetate/nhexane separation

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Chinese Journal of Chemical Engineering 2018年第10期26卷 2023-2033页

作者： liping lü lin zhu huimin liu hang li Shirui Sun Key laboratory of Gas Process Engineering School of Chemistry and Chemical Engineering Southwest Petroleum University School of Chemistry and Chemical Engineering Yangtze Normal University

Continuous homogenous azeotropic distillation(ChAD) and pressure-swing distillation(PSD) are explored to separate a minimum-boiling azeotropic system of ethyl acetate and n-hexane. The ChAD process with acetone as the entrainer and the PSD process with the pressures of 0.1 MPa and 0.6 MPa in two columns are designed and simulated by Aspen Plus. The operating conditions of the two processes are optimized via a sequential modular approach to obtain the minimum total annual cost(TAC). The computational results show that the partially heat integrated pressure-swing distillation(hIPSD) has reduced in the energy cost and TAC by 40.79% and 35.94%, respectively, than the conventional PSD, and has more greatly reduced the energy cost and TAC by 62.61% and 49.26% respectively compared with the ChAD process. The comparison of ChAD process and partially hIPSD process illustrates that the partially hIPSD has more advantages in averting the product pollution, energy saving, and economy.

关键词： Continuous homogenous azeotropic distillation Pressure-swing distillation Ethyl acetate/n-hexane Azeotrope

EFFECT OF NANOCRYSTAllIZATION ON ThE SCAlING OF NiAl AT 1000℃ IN AIR

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Acta Metallurgica Sinica(English letters) 2002年第1期15卷 77-80页

作者： S.l. Yang Fuhui Wang S.l. zhu Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The oxidation behavior of a magnetron sputtered nanocrystalline NiAl coating was investigated at 1000℃ in air. Comparing with cast NiAl and NiAl-0.1at.%Y alloys reveals influences of nanocrystallization as well as yttrium addition on the oxidation behavior of NiAl. Results show that a phase transformation from metastable θ-Al2O3 to stable a-Al2O3 occurred in scales, which was accelerated by the microcrystallization and retarded by the addition of Y. The addition of Y as well as the nanocrystallization reduced the void formation at the interface between the scale and the substrate.

关键词： nanocrystalline NiAl NiAlY oxidation

First principles calculations on the thermoelectric properties of bulk Au2S with ultra-low lattice thermal conductivity

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Chinese Physics B 2020年第8期29卷 108-114页

作者： Y Y Wu X l zhu h Y Yang Z G Wang Y h li B T Wang School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Institute of high Energy Physics Chinese Academy of SciencesBeijing 100049China Spallation Neutron Source Science Center Dongguan 523808China School of Materials Science and Engineering Hunan University of Science and TechnologyXiangtan 411201China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Sulfide nanocrystals and their composites have shown great potential in the thermoelectric(TE)field due to their extremely low thermal *** a solid and hollow metastable Au2S nanocrystalline has been successfully ***,we study the TE properties of this bulk Au2S by first-principles calculations and semiclassical Boltzmann transport theory,which provides the basis for its further experimental *** results indicate that the highly twofold degeneracy of the bands appears at theΓpoint in the Brillouin zone,resulting in a high Seebeck ***,Au2S exhibits an ultra-low lattice thermal conductivity(~0.88 W·m^-1·K^-1 at 700 K).At 700 K,the thermoelectric figure of merit of the optimal p-type doping is close to 1.76,which is higher than 0.8 of ZrSb at 700 K and 1.4 of PtTe at 750 *** work clearly demonstrates the advantages of Au2S as a TE material and would greatly inspire further experimental studies and verifications.

关键词： first principles calculation thermodynamic transport properties

SEQUENTIAl　MUlTISTEP　REACTIONS　CATAlYZED　BY　POlYMER－ANChORED　BIFUNCTIONAl　CATAlYSTS

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Chinese Chemical letters 1995年第12期6卷 1029-1032页

作者： zhu, h Chen, lB Jiang, YY Acad Sinica Guangzhou Inst Chem Guangzhou 510650 Peoples R China Acad Sinica Inst Chem Beijing 100080 Peoples R China

By the reaction of 1,8-diazabicyclo(5,4,0 )undec-7-ene (DBU) and chloromethylated polystyrene, polymer-anchored catalysts, PCS-DBU,are prepared and found to be effective to catalyze sequentially the cyclization of propylene oxide and the transesterification of propylene carbonate with methanol. It is found that low degree of ring substitution (DRS) of chloromethylated polystyrene, high reaction temperature and the addition of potassium iodide can accelerate the reaction. PCS-DBU can easily be recovered after reaction by filtration and can be reused for many runs.

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Permian palynofioras from Yongchang and Sunan of Gansu Province and their phytoprovincial characteristics

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Chinese Science Bulletin 1999年第9期44卷 831-834页

作者： Shu, OY zhu, hC Wang, h Chinese Acad Sci Nanjing Inst Geol & Palaeontol Nanjing 210008 Peoples R China Chinese Acad Sci Lanzhou Inst Geol Lanzhou 730000 Peoples R China

The Early Permian (Shansi + lower Shihhotse Formations) palynofloras of longshoushan are dominated by Cathaysian-Euramerican common forms, mainly composed of pteridophytic and pteridospermous spores. But up to the lower Shihhotse Formation, gymnosperms greatly developed, and they possibly already dominated the vegetation in the Upper Shihhotse Formation; while in the late late Permian, they indicate a strong colour of Subangara area. In other words, during the whole Permian, the Cathaysian flora had a history from prosperity to decline, and Subangara plants might have had a reverse tendency there.

关键词： palynoflora phytoprovince Permian Gansu Province.