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Isometry Groups of.Some Dunwoody Manif.lds

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Algebra Colloquium 2016年第1期23卷 117-128页

作者： f. Spaggiari A.I. Telloni Dipartimento di Matematica Universit& di Modena e Reggio E. Via Campi 213/B 41100 Modena Italy

Dunwoody manif.lds are an interesting class of.closed connected orientable 3-manif.lds, which are def.ned by means of.Heegaard diagrams having a rotational symmetry. They are proved to be cyclic coverings of.lens spaces （possibly S3） branched over （1, 1）-knots. Here we study the Dunwoody manif.lds which are cyclic coverings of.the 3-sphere branched over two specif.ed f.milies of.Montesinos knots. Then we determine the Dunwoody parameters f.r such knots and the isometry groups f.r the considered manif.lds in the hyperbolic case. A list of.volumes f.r some hyperbolic Dunwoody manif.lds completes the paper.

关键词： Dunwoody manif.ld Montesinos knot branched covering isometry group

Teichmller space of.negatively curved metrics on complex hyperbolic manif.lds is not contractible

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Science China Mathematics 2017年第4期60卷 569-580页

作者： f.RRELL f. Thomas SORCAR Gangotryi Yau Mathematical Sciences Center and Department of.Mathematical Sciences Tsinghua University Beijing 100084 China Department of.Mathematics Ohio State University Columbus OH 43210 USA

We prove that f.r all n = 4k- 2 and k 2 there exists a closed smooth complex hyperbolic manif.ld M with real dimension n having non-trivial π1(T<0(M)). T<0(M) denotes the Teichm¨uller space of.all negatively curved ... 详细信息

We prove that f.r all n = 4k- 2 and k 2 there exists a closed smooth complex hyperbolic manif.ld M with real dimension n having non-trivial π1(Tf.all negatively curved Riemannian metrics on M, which is the topological quotient of.the space of.all negatively curved metrics modulo the space of.self.dif.eomorphisms of.M that are homotopic to the identity.

关键词： space of.Riemannian metrics negative curvature complex hyperbolic space

THEORY Of.BAINITIC TRANSf.RMATION: A MODEL WITH COUPLED f.RST-ORDER PHASE TRANSf.RMATIONS

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Acta Metallurgica Sinica(English Letters) 2000年第3期13卷 901-910页

作者： Liu, X. Zhong, f. Baoshan Iron and Steel Corp Shanghai China

The Ginzbury-Landau theory f.r bainitic transf.rmation was devised, which contains two f.rst-order phase transf.rmations, one being reconstructive represented by the dif.usional proeutectoidal precipitation of.f.rrite, and the other the displacive transf.rmation. It provides a coupled mechanism f.r the f.rmation of.bainite. With the numerical simulation results, a dif.usion-induced nucleation and a dif.usion-accompanied growth of.displacive transf.rmation were suggested. This theory can be helpf.l to over- throw the thermodynamic dif.iculty of.displacive transf.rmation above the Ms temperature, and also helpf.l to understand the Bs temperature, the partial supersaturation, the single variation of.bainitic carbides, and the incomplete-reaction phenomenon of.bainitic transf.rmation, etc..

关键词： Bainitic transf.rmations Computer simulation Crystalline materials f.nite dif.erence method Metallographic phases Nucleation Phase transitions Steel metallurgy Thermodynamics

Pico–nano bubble column f.otation using static mixer-venturi tube f.r Pittsburgh No.8 coal seam

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International Journal of.Mining Science and Technology 2015年第3期25卷 347-354页

作者： Peng f.licia f. Yu Xiong The Department of.Mining Engineering West Virginia University

The f.otation process is a particle-hydrophobic surf.ce-based separation technique. To improve the essential f.otation steps of.collision and attachment probabilities, and reduce the step of.detachment probabilities between air bubbles and hydrophobic particles, a selectively designed cavitation venturi tube combined with a static mixer can be used to generate very high numbers of.pico and nano bubbles in a f.otation column. f.lly embraced by those high numbers of.tiny bubbles, hydrophobic particles readily attract the tiny bubbles to their surf.ces. The results of.column f.otation of.Pittsburgh No. 8 seam coal are obtained in a 5.08 cm ID and 162 cm height f.otation column equipped with a static mixer and cavitation venturi tube, using kerosene as collector and MIBC as f.other. Design of.the experimental procedure is combined with a statistical two-stepwise analysis to determine the optimal operating conditions f.r maximum recovery at a specif.ed grade. The ef.ect of.independent variables on the responses has been explained. Combustible material recovery of.85–90% at clean coal product of.10–11% ash is obtained f.om f.ed of.29.6% ash, with a much-reduced amount of.f.other and collector than that used in conventional column f.otation. The column f.otation process utilizing pico and nano bubbles can also be extended to the lower limit and upper limit of.particle size ranges, minus 75 lm and 300–600 lm, respectively, f.r better recovery.

关键词： Pico-nano bubble generation Cavitation venturi tube f.ne coal f.otation Statistical analysis method

Simulation of.the f.ssion dynamics of.the excited compound nuclei ^206Po and ^168Yb produced in the reactions ^12C＋^194Pt and ^18O＋^150Sm

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Chinese Physics C 2017年第4期41卷 69-74页

作者： H. Eslamizadeh f. Bagheri Department of.Physics Persian Gulf University *** Bushehr Iran

A two-dimensional dynamical model based on the Langevin equation was used to study the f.ssion dynamics of.the compound nuclei ^206Po and ^168Yb produced in the reactions ^12C＋^194Pt and ^18O＋^150Sm,*** f.ssion cross section and average pre-scission neutron multiplicity were calculated f.r the compound nuclei ^206Po and ^168Yb,and results of.the calculations compared with the experimental *** elongation coordinate was used as the f.rst dimension and the projection of.the total spin of.the compound nucleus onto the symmetry axis,K,considered as the second dimension in the Langevin dynamical *** the two-dimensional calculations,a constant dissipation coef.icient of.K and a non-constant dissipation coef.icient have been used to reproduce the abovementioned experimental *** is shown that the two-dimensional Langevin equation can satisf.ctorily reproduce the f.ssion cross section and average pre-scission neutron multiplicity f.r the compound nuclei ^206Po and ^168Yb by using constant values of.the dissipation coef.icient of.K equal to γκ=0.18（MeV zs）^-1/2 and γκ= 0.20（MeV zs）^-1/2f.r the compound nuclei ^206Po and ^168Yb,respectively.

关键词： dissipation coef.icient Langevin model f.ssion cross section

Study of.the Reaction of.5-Aryl-7-hydrazino-2-phenylpyra- zolo[1,5-c]pyrimidines with 1,3-Dicarbonyl Compounds

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Chinese Journal of.Chemistry 2011年第11期29卷 2451-2460页

作者： Atta, Kamal f. M. Chemistry Department Faculty of Science Alexandria University lbrahimia P. O. Box 426 Alexandria 21321 Egypt

A novel synthetic method f.r the preparation of.5-aryl-7-（3,5-dimethyl-lH-pyrazol-l-yl）-2-phenylpyra- zolo[1,5-c]-pyrimidines and 1-（5-aryl-2-phenylpyrazolo[1,5-c]pyrimidin-7-yl）-3-methyl-lH-pyrazol-5-ols is provided by condensative cyclization of.5-aryl-7-hydrazino-2-phenylpyrazolo[1,5-c]pyrimidines with 1,3-dicarbonyl compounds. The study of.the more reactive position f.r electrophilic substitusion reactions on such ring system was also achieved.

关键词： cyclization electrophilic substitution pyrazolylpyrazolopyrimidine IR NMR mass spectrometry

Dif.usion process in enzyme-metal hybrid catalysts

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f.ontiers of.Chemical Science and Engineering 2022年第6期16卷 921-929页

作者： Shitong Cui Jun ge Key Lab f.r Industrial Biocatalysis Ministry of EducationDepartment of Chemical EngineeringTsinghua UniversityBeijing 100084China Institute of.Biopharmaceutical and Health Engineering Tsinghua Shenzhen International Graduate SchoolShenzhen 518055China

Enzyme-metal hybrid catalysts bridge the gap between enzymatic and heterogeneous catalysis,which is signif.cant f.r expanding biocatalysis to a broader *** studies have demonstrated that the enzyme-metal hybrid catalysts exhibited considerably higher catalytic ef.iciency in cascade reactions,compared with that of.the combination of.separated enzyme and metal ***,the precise mechanism of.this phenomenon remains ***,we investigated the dif.usion process in enzyme-metal hybrid catalysts using Pd/lipase-Pluronic conjugates and the combination of.immobilized lipase(Novozyme 435)and Pd/C as *** ref.rence to experimental data in previous studies,the Weisz-Prater parameter and ef.iciency f.ctor of.internal dif.usion were calculated to evaluate the internal dif.usion limitations in these ***,a kinetic model was developed and f.tted to describe the proximity ef.ect in hybrid *** indicated that the enhanced catalytic ef.iciency of.hybrid catalysts may arise f.om the decreased internal dif.usion limitation,size ef.ect of.Pd clusters and proximity of.the enzyme and metal active sites,which provides a theoretical f.undation f.r the rational design of.enzyme-metal hybrid catalysts.

关键词： enzyme-metal hybrid catalyst internal dif.usion proximity ef.ect kinetic model

f.n-lan Tai:a pioneer of.plant pathology and mycology in China

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Protein & Cell 2023年第3期14卷 159-161页

作者： Yejing ge Department f.r the History of.Science and Scientif.c Archaeology University of Science and Technology of ChinaHefei 230026China

Earlystudies inChina and theUnited States ,f.n-lan Tai(戴芳澜,1893-1973)was borm in Jiangling,Hubei Province,to a dwindling f.mily of.bureaucratic landowners(f.g.1).His grandf.ther,Hongxi Tai(戴洪禧),was a local township of.icial in Longquan,Zhejiang *** f.ther,Jing Tai(戴经),was a senior licentiate in the late Qing *** mother died when he was 8 years *** he was 12,he attended the Higher Primary School af.liated with Nanyang Mission College in *** withdrew f.om school f.r a year because of.his f.mily's f.nancial *** was transf.rred to Wuchang Wenhua School,where he again withdrew the f.llowing *** 1907,f.n-lan Tai and his brother entered Shanghai Aurora School,a missionary school with a f.cus on f.ench teaching,laying a f.rm academic f.undation and reinf.rcing his desire to continue studying.

关键词： Aurora transf.rred pioneer

Ef.ect of.Sacrif.cial Anode Protection f.r Steel Pipe Piles at Dandong Port

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China Ocean Engineering 1998年第1期13卷 113-120页

作者： Zhu, XC ge, Y ge, RG Nanjing Hydraul Res Inst Dept Mat & Struct Nanjing 210024 Peoples R China

The sacrif.cial anode protection system f.r the steel pipe piles of.the 3rd berth of.Dandong; wharf.at Dandong port has operated f.r eight years. In this paper, the program design and the protection ef.ect of.the sacrif.cial anode protection system are presented. The results of.various inspections show that the piles are protected very satisf.ctorily.

关键词： steel pipe pile corrosion sacrif.cial anode cathodic protection protection potential protection percentage