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Simulation on effect of throat contraction ratio and strake stagger angle on flow field and aerodynamic performance of scrampressor

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航空动力学报 2017年第5期32卷 1183-1194页

作者： YANG Ling ZHONG jing-jun han ji-ang Marine Engineering College Dalian Maritime University

The design methods of typical supersonic aircraft intakes and shock wave compression technology have been applied to ram-rotor,an attractive compression system.A ram-rotor is of a typical structure including the compression ramp,the throat and the subsonic diffuser;a scrampressor is similar to ram-rotor,the only difference is that scrampressor has no subsonic *** work was the continuation of the preparatory *** order to further study the effect of throat contraction ratio and strake stagger angle on the flow field and performance of a scrampressor,the flow field of a scrampressor with a three-dimensional flow path was numerically simulated with different throat contraction ratios and strake stagger *** results indicated that the optional aerodynamic performance of a scrampressor could be achieved with an adiabatic efficiency of 0.8413atotal pressure recovery coefficient of 0.8446,a total pressure ratio of 7.14 and a static pressure ratio of 5.17for a throat contraction ratio of 0.6 and a strake stagger angle of 12°.It was therefore concluded that an appropriate decrease in throat contraction ratio and an increase in strake stagger angle could help the comprehensive improvement of a scrampressor in performance.

关键词： scrampressor flow field aerodynamic performance throat contraction ratio strake stagger angle

Unconstrained Optimization Reformulations of Equilibrium Problems

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Acta Mathematica Sinica,English Series 2009年第3期25卷 343-354页

作者： Li Ping ZhanG ji Ye han w Department of Mathematical Sciences Tsinghua University Beijing 100084 P. R. China Institute of Applied Mathematics Academy of Mathematics & Systems Science Chinese Academy of Sciences Beijing 100190 P. R. China

We generalize the D-gap function developed in the literature for variational inequalities to a general equilibrium problem （EP）. Through the D-gap function, the equilibrium problem is cast as an unconstrained minimization problem. We give conditions under which any stationary point of the D-gap function is a solution of EP and conditions under which it provides a global error bound for EP. Finally, these results are applied to box-constrained EP and then weaker conditions are established to obtain the desired results for box-constrained EP.

关键词： equilibrium problems D-gap function error bound unconstrained optimization

Effect of Meridional Characteristic Angle on Aerodynamic Performance of Ram-Rotor

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Journal of Thermal Science 2020年第3期29卷 753-762页

作者： han ji'ang GUAN jian ZHONG jingjun CHEN Luting Naval Architecture and Ocean Engineering College Dalian Maritime UniversityDalian 116026China Merchant Marine College Shanghai Maritime UniversityShanghai 201306China

A kind of meridional concept which has a shape of contraction-expansion(Con-Exp)was applied to the ram-rotor in the paper,and detailed numerical simulation to understand the impact of meridional shape and geometric characteristic angle on the aerodynamic behavior of ram-rotors has been *** to baseline,there was a positive effect in intensifying shock train and suppressing low momentum fluid in Con-Exp scheme,and the pressure ratio and efficiency of Con-Exp scheme increased by 2.075%and 3.160%,*** the contracting angle was increasing,supersonic flow at and after throat region accelerated remarkably,and the static pressure rise was decreased *** terminating shock train was transformed to terminating shock,and the efficiency of ram-rotor was unfavorable to improve due to low throttle *** expanding angle rose,the terminating shock moved forward and turned to shock train *** pressure rise capacity and throttling ability of ram-rotor were *** low momentum fluid was accumulated near the middle and upper flow-path,yielding greater flow loss at large expanding angle.

关键词： ram-rotor meridional shape contracting angle expanding angle numerical simulation

Numerical simulation of the three-dimensional flow-path in a ram-rotor

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航空动力学报 2010年第6期25卷 1358-1365页

作者： han ji-ang ZHONG jing-jun YAN Hong-ming Marine Engineering College Dalian Maritime UniversityDalian 116026China School of Energy Science and Engineering Harbin institute of TechnologyHarbin 150001China

A kind of three-dimensional flow-path of the ram-rotor was designed in this paper according to the design method of the typical supersonic intake of aircraft and missiles,especially the design method of the compression ramp,the throat and the subsonic *** design Mach number of the flow-path was based on the averaged relative Mach number,regardless of the change of incoming Mach number along radial direction of the ***,the flowfield of the designed flow-path was simulated numerically with computational fluid dynamics software at design *** purpose of simulation was to obtain the details of the flowfield,including the structure of the shock wave system,position of flow separation zone,and so *** performance of the ram-rotor was also *** numerical results show the structure of the shock wave system in the flow-path is similar to that in the supersonic *** improve the overall performance of the ram-rotor,the reasonable compromise between the total pressure ratio and the isentropic adiabatic efficiency should be *** structure optimization of the flow-path and the configuration of the shock wave system have great influence on the performance of the ram-rotor.

关键词： ram-rotor flow-path supersonic intake numerical simulation design point

Effect of Vane Opening on Aerodynamic Performance of the Ram-rotor Test System

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Journal of Thermal Science 2016年第3期25卷 207-215页

作者： han ji-ang GUAN jian ZHONG jingjun YUAN Chenguang Marine Engineering College Dalian Maritime University

In order to research the influence of adjustable vane on the aerodynamic performance of the ram-rotor test system, FLUENT soft-ware has been adopted to simulate the flow passage of the ram-rotor test system numerically. The vane opening is controlled by changing the stagger angle of the vane blades. Results show that flow uniformity of vane outlet is influenced by the vane openings, which has an impact on the aerodynamic loss to some extent. Total pressure ratio, adiabatic efficiency and mass flow rate can be regulated by different openings of the vane. Compared with -8° vane opening, top efficiency of the ram-rotor increases by about 13.8% at ＋6° opening. And total pressure ratio drops by 5.87%. The rising opening increases the relative Mach number at inlet of the ram-rotor and weakens the intensity of the tip clearance leakage, which comes to a decreasing aerodynamic loss.

关键词： adjustable vane ram-rotor test system aerodynamic performance numerical simulation

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Neuroscience Bulletin 2017年第2期33卷 238-246页

作者： Rong Zhang Hong-Feng Zhang ji-Sheng han Song-Ping han Neuroscience Research Institute Peking UniversityBeijing 100191China Department of Neurobiology School of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China Key Laboratory for Neuroscience Ministry of Education/National Health and Family Planning CommissionPeking UniversityBeijing 100191China Fujian Provincial Key Laboratory of Neurodegenerative Disease and Aging Research Institute of NeuroscienceCollege of MedicineXiamen UniversityXiamen 361005China

Autism spectrum disorder（ASD） is a highly heritable neurodevelopmental disorders characterized by impaired social interactions, communication de？cits, and repetitive behavior. Although the mechanisms underlying its etiology and manifestations are poorly understood,several lines of evidence from rodent and human studies suggest involvement of the evolutionarily highly-conserved oxytocin（OXT） and arginine-vasopressin（AVP）, as these neuropeptides modulate various aspects of mammalian social behavior. As far as we know, there is no comprehensive review of the roles of the OXT and AVP systems in the development of ASD from the genetic aspect. In this review, we summarize the current knowledge regarding associations between ASD and single-nucleotide variants of the human OXT-AVP pathway genes OXT, AVP, AVP receptor 1a（AVPR1a）, OXT receptor（OXTR）, theoxytocinase/vasopressinase（LNPEP）, and ADP-ribosyl cyclase（CD38）.

关键词： Oxytocin Arginine-vasopressin Singlenucleotide polymorphisms Autism spectrum disorder

Busting the efficiency of SAPO-34 catalysts for the methanol-to-olefin conversion by post-synthesis methods

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Chinese Journal of Chemical Engineering 2020年第8期28卷 2022-2027页

作者： Guoju Yang ji han Yujun Huang Xiaoxin Chen Valentin Valtchev State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin University2699 Qianjin StreetChangchun 130012China International Center of Future Science Jilin University2699 Qianjin StreetChangchun 130012China Normandie Univ ENSICAENUNICAENCNRSLaboratoire Catalyse et Spectrochimie6 Marechal Juin14050 CaenFrance

As an effective non-petroleum based process for producing light olefins, the methanol-to-olefin(MTO) route has become an indispensable alternative to the industrial production of light olefins. The silicoaluminophosphate SAPO-34 zeolite(CHA-type structure) has proven to be an efficient industrial catalyst for the production of ethylene and propylene by the MTO reaction. However, the inherent structure and related diffusion limitations of SAPO-34 limit the mass transport and thus cause rapid deactivation of the catalyst. Fabrication of hierarchical SAPO-34 zeolite is one of the most effective strategies to address the intrinsic diffusion limitation. As simple, inexpensive, and efficient approach, the post-synthetic route has attracted considerable attention and widely used to introduce secondary meso-/macropores into the microporous SAPO-34 material. Significant effort has been dedicated to the development of post-synthesis strategies to prepare hierarchical SAPO-34 zeolite, thereby enhancing its catalytic performance in the MTO process. This mini-review addresses the post-synthesis preparation of hierarchical SAPO-34 catalysts and their MTO performance. Furthermore, some current problems and prospects of the post-synthesis route to hierarchical SAPO-34 catalysts are also revised. We expect this minireview to inspire the more efficient preparation of hierarchical SAPO-34 catalysts for the MTO process.

关键词： Zeolites SAPO-34 Post-synthesis treatment Hierarchical MTO

The synthetic strategies of hierarchical TS-1 zeolites for the oxidative desulfurization reactions

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2227-2234页

作者： Guoju Yang ji han Yue Liu Ziyi Qiu Xiaoxin Chen State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of ChemistryJilin UniversityChangchun 130012China International Center of Future Science Jilm UniversityChangchun 130012China Department of Chemistry and Catalysis Research Center Technische Universitat MunchenLichtenbergstrasse 485747 GarchingGermany

With the increasingly stringent standards for limiting sulfide content in liquid fuels,oxidative desulfurization(ODS)has become a promising ultra-deep desulfurization process in fuel ***-1 zeolites show great potential as catalysts for ODS reactions,due to its remarkable oxidation activity at low temperatures and ***,the inherent microporous structure of conventional TS-1 zeolites restricts the mass transportation and renders the active sites in the microporous space of TS-1 zeolites inaccessible for bulky aromatic organosulfur *** of hierarchical TS-1 zeolites by incorporating meso-/macropores into microporous TS-1 zeolites is an effective strategy to improve mass *** recent years,abundant efforts have been dedicated to developing synthetic strategies of hierarchical TS-1 zeolite,thereby improving its catalytic performance in the ODS *** mini-review addresses the synthetic methods of hierarchical TS-1 catalysts and their catalytic performance in the ODS *** addition,some current problems and prospects of synthesis routes for constructing hierarchical TS-1 catalysts have also been *** expect this mini-review to shed light on the more efficient preparation strategies of hierarchical TS-1 zeolites for the ODS process.

关键词： Zeolites TS-1 Synthesis Hierarchical ODS

Exact Solutions Expressible in Rational Formal Hyperbolic and Elliptic Functions for Nonlinear Differential-Difference Equation

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Communications in Theoretical Physics 2008年第8期50卷 303-308页

作者： BAI Cheng-jie ZHAO Hong han ji-Guang School of Communication Shandong Normal University Jinan 250014 China School of Physical Science and Information Engineering Liaocheng University Liaocheng 252059 China

A new approach is presented by means of a new general ansitz and some relations among Jacobian elliptic functions, which enables one to construct more new exact solutions of nonlinear differential-difference equations. As an example, we apply this new method to Hybrid lattice, diseretized mKdV lattice, and modified Volterra lattice. As a result, many exact solutions expressible in rational formal hyperbolic and elliptic functions are conveniently obtained with the help of Maple.

关键词： nonlinear differential-difference equations new approach exact solutions