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CATALYTIC ACTIVITIES OF RARE-EARTH CALIXARENE COMPLEXES IN POLYMER SYNTHESES

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Chinese Journal of Polymer Science 2005年第6期23卷 593-602页

作者： Zhi-quan shen Institute of Polymer Science Zhejiang University Hangzhou 310027 China

The studies of our group on the catalytic activities of rare earth calixarene complexes in polymer syntheses are reviewed. Rare earth calixarene complexes are effect catalysts for the polymerizations of butadiene, isoprene, ethylene, styrene, propylene oxide, styrene oxide, trimethylene carbonate and 2,2-dimethyl-trimethylene carbonate.

关键词： Rare earth complex Calixarene Polymer synthesis.

A New Molecular Label Applied to the Study of the Yellow Sea Green Tide

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Journal of Ocean University of China 2019年第6期18卷 1507-1514页

作者： shen Weijie HE Yuan shen Songdong Department of Cell Biology College of Biology and Basic Medical Sciences Soochow University

From 2007 to 2017,large-scale green tides occurred every year in the Yellow Sea of China,and Ulva prolifera was the main species leading to the green *** this study,we used the Polymerase chain reaction and 3'Rapid-amplification of c DNA ends technique to amplify the nr DNA-LSU and IGS sequences in *** and one species of *** techniques showed 3259 bp of nrD NA-LSU and 3388 bp of IGS in *** and 3282 bp nr DNA-LSU and 3059 bp IGS in Blidingia *** the same time,tandem repeats,short dyads,palindromic and multiple simple repeat sequences in the IGS sequence were found by analyzing the structure of the IGS sequence in *** and Blidingia sp.G+C contents of the IGS sequence in *** and Blidingia *** 52.42% and 53.09%,*** divided the *** into two types according to the morphological *** the specimens of *** from the Qingdao coastal area,Jiangsu coastal area and the Yellow Sea have different morphologies,their ITS and IGS sequences are almost ***,the main species of the green tides in the Qingdao coastal area,Jiangsu coastal area and the Yellow Sea are the same and have the same origin.

关键词： LSU IGS Ulva prolifera green tide morphological characteristics

Fundamental influence of irreversible stress-strain properties in solids on the validity of the ramp loading method

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Matter and Radiation at Extremes 2024年第6期9卷 94-104页

作者： Jingxiang shen Wei Kang Center for Applied Physics and Technology and College of EngineeringPeking UniversityBeijing 100871China

The widely used quasi-isentropic ramp loading technique relies heavily on back-calculation methods that convert the measured free-surface velocity profiles to the stress-density states inside the compressed *** back-calculation methods are based on one-dimensional isentropic hydrodynamic equations,which assume a well-defined functional relationship P(p)between the longitudinal stress and density throughout the entire flow ***,this kind of idealized stress-density relation does not hold in general,because of the complexities introduced by structural phase transitions and/or elastic-plastic *** and to what extent these standard back-calculation methods may be affected by such inherent complexities is still an unsettled ***,we present a close examination using large-scale molecular dynamics(MD)simulations that include the detailed physics of the irreversibly compressed solid *** back-calculate the stress-density relation from the MD-simulated rear surface velocity profiles and compare it directly against the stress-density trajectories measured from the MD simulation *** exist in the cases studied here,and these turn out to be related to the irreversibility between compression and *** and compression waves are observed to propagate with different sound velocities in some parts of the flow field,violating the basic assumption of isentropic hydrodynamic models and thus leading to systematic back-calculation *** particular,the step-like feature of the P(p)curve corresponding to phase transition may be completely missed owing to these *** kind of mismatch between inherent properties of matter and the basic assumptions of isentropic hydrodynamics has a fundamental influence on how the ramp loading method can be applied.

关键词： field. irreversible solids

DSA analysis of hepatic arteriovenous fistula concurrent with hepatic cancer and its clinical significance

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World Journal of Gastroenterology 2000年第6期6卷 872-876页

作者： Guo WP Zhang hx Wang ZM Wang YQ Ni DH Li WX Guan Y Fourth Mil Med Univ Tangdu Hosp Dept Intervent Radiol Xian 710038 Shaanxi Provinc Peoples R China

INTRODUCTIONIntervention therapy has become one of the maintherapies of hepatic *** of hepatic arterial perfusion andembolization has provided opportunities for asecondary operation on patients with intermediateand ad... 详细信息

关键词： liver neoplasms hypertension portal hepatic arteriovenous fistula angiography digital subtraction

Preface:Special topic on Precise Catalysis Science and Technology

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Science China Chemistry 2021年第7期64卷 1063-1064页

作者： Wenjie shen State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Nanoparticles,clusters and single-atoms constitute the major types of metal *** size variation of metal species,known as size effect in heterogeneous catalysts,not only changed the geometric and electronic structure of metal atoms,but also altered their anchoring strength with the immobilizing supports,showing distinctively varied activities.A gradual accumulation of large amounts of experimental data and theoretical calculations has unambitiously verified that the size of the metal species played a crucial role in determining the catalytic performance with respect to the geometric and electronic structures of active sites.

关键词： verified size determining

Holomorphic Maps from Sasakian Manifolds into Khler Manifolds

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Chinese Annals of Mathematics,Series B 2013年第4期34卷 575-586页

作者： Bin shen Yibing shen Xi ZHANG Department of Mathematics Southeast University Department of Mathematics Zhejiang University Department of Mathematics Zhejiang University

The authors consider ±（Φ, J）-holomorphic maps from Sasakian manifolds into Koihler manifolds, which can be seen as counterparts of holomorphic maps in Kiihler ge- ometry. It is proved that those maps must be harmonic and basic. Then a Schwarz lemma for those maps is obtained. On the other hand, an invariant in its basic homotopic class is obtained. Moreover, the invariant is just held in the class of basic maps.

关键词： Sasakian manifold Harmonic Schwarz lemma Homotopic invariant

Rational Solutions of First Order Algebraic Ordinary Differential Equations

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Journal of Systems Science & Complexity 2024年第2期37卷 567-580页

作者： FENG Shuang shen Liyong School of Physical and Mathematical Sciences Nanjing Tech UniversityNanjing 211816China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

Let f(t,y,y')=∑ _(i=0)^(n )a_(i)(t,y)y'^(i)=0 be an irreducible first order ordinary differential equation with polynomial *** in 1998 proved that there exists a constant C such that every rational solution of f(t,y,y')=0 is of degree not greater than *** show that this degree bound C depends not only on the degrees of f in t,y,y' but also on the coefficients of f viewed as the polynomial in t,y,y'.In this paper,the authors show that if f satisfies deg(f,y)0,then the degree bound C only depends on the degrees of f in t,y,y',and furthermore we present an explicit expression for C in terms of the degrees of f in t,y,y'.

关键词： Degree bound first order AODE height rational solution

Ca-and Mg-rich waste as high active carrier for chemical looping gasification of biomass

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Chinese Journal of Chemical Engineering 2021年第10期34卷 145-154页

作者： Xin Niu Laihong shen School of Energy and Power Engineering Nanjing University of Science and TechnologyNanjing 210094China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Chemical looping gasification(CLG)is a promising technology for high-quality syngas *** key issue to successful CLG is the selection of high-performance oxygen *** this study,several Ca-and Mg-rich steelmaking wastes from steel industry,such as blast furnace slag(BF slag),blast furnace dust(BF dust)and Linz-Donawitz converter slag(LD slag),were used as oxygen carriers in chemical looping gasification of *** results showed that the reducibility of Ca-and Mg-rich waste,especially LD slag and BF dust,was superior to that of *** long-term operation,the cyclic stability of steelmaking waste was *** dust showed a poor stability,while the other carrier(hematite,BF slag or LD slag)presented an excellent stability during multiple redox cycles in spite of partial sintering and ***,the effects of supply oxygen coefficient(O/B ratio)and reaction temperature on CLG of biomass were *** results revealed that Ca-and Mg-rich waste exhibited a higher syngas production compared to *** higher performance could be attributed to the improved reduction rate of Fe2O3 and gasification rate of biomass by Ca or Mg in steelmaking *** addition,LD slag exhibited the higher gas value at the O/B ratio of 1 at 900℃.As a consequence,LD slag was an appropriate oxygen carrier for CLG of biomass in terms of perfect reducibility,superior cyclic stability and high reactivity.

关键词： Biomass Syngas Gasification Ca-and Mg-rich waste Chemical looping

Non-equilibrium thermodynamic analysis of coupled heat and moisture transfer across a membrane

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Chinese Journal of Chemical Engineering 2022年第4期35卷 497-506页

作者： Zhijie shen Jingchun Min Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China

Non-equilibrium thermodynamics theory is used to analyze the transmembrane heat and moisture transfer process,which can be observed in a membrane-type total heat exchanger(Thx).A theoretical model is developed to simulate the coupled heat and mass transfer across a membrane,total coupling equations and the expressions for the four characteristic parameters including the heat transfer coefficient,molardriven heat transfer coefficient,thermal-driven mass transfer coefficient,and mass transfer coefficient are derived and provided,with the Onsager’s reciprocal relation being confirmed to verify the rationality of the *** are conducted to investigate the effects of the membrane property and air state on the coupling transport *** results show that the four characteristic parameters directly affect the transmembrane heat and mass fluxes:the heat and mass transfer coefficients are both positive,meaning that the temperature difference has a positive contribution to the heat transfer and the humidity ratio difference has a positive contribution to the mass *** molar-driven heat transfer and thermal-driven mass transfer coefficients are both negative,implying that the humidity ratio difference acts to reduce the heat transfer and the temperature difference works to diminish the mass *** mass transfer affects the heat transfer by 1%–2%while the heat transfer influences the mass transfer by7%–14%.The entropy generation caused by the temperature difference-induced heat transfer is much larger than that by the humidity difference-induced mass transfer.

关键词： Membrane Non-equilibrium thermodynamics Heat transfer Mass transfer Coupling effect