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Synthesis of spherical nano-ZSm-5 zeolite with intergranular mesoporous for alkylation of ethylbenzene with ethanol to produce m-diethylbenzene

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Chinese Journal of Chemical Engineering 2024年第3期67卷 298-309页

作者： Siyue Wang Jinhong Li Qingxin Xu Shengjie Song Yu'ni Jiang Lidong Chen Xin Shi Weiguo Cheng Faculty of Chemistry and Chemical Engineering Liaoning Normal UniversityDalian 110629China Beijing Key Laboratory of Ionic Liquids Clean Process Key Laboratory of Green Process and EngineeringInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China

Catalytic synthesis of m-diethylbenzene(m-DEB)through alkylation of ethylbenzene(EB)may be a promising alternative route in comparison with traditional rectification of mixed DEB,for which the top priority is to develop efficient and stable heterogeneous ***,the spherical nano-ZSm-5 zeolite with abundant intergranular mesoporous is synthesized by the seed-mediated growth method for alkylation of EB with ethanol to produce *** results show that the spherical nano-ZSm-5 zeolite exhibits better stability and higher alkylation activity at a lower temperature than those of commercial micropore *** then,the spherical nano-ZSm-5 is further modified by La_(2)O_(3) through acid treatment followed by immersion *** acid treatment causes nano-ZSm-5 to exhibit the increased pore size but decreased the acid sites,and subsequent La_(2)O_(3) loading reintroduces the weak acid *** a result,the HNO_(3)-La_(2)O_(3)-modified catalyst exhibits a slight increase in EB conversion and DEB yield in comparison with unmodified one,and meanwhile,it still maintains high m-DEB *** catalyst after acid treatment achieves higher catalytic stability besides maintaining the high alkylation activity of EB with *** present study on the spherical nano-HZSm-5 zeolite and its modification catalyst with excellent alkylation ability provides new insights into the production of mDEB.

关键词： Zeolite modification Alkylation reaction m-diethylbenzene Catalyst Fixed-bed

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Regression analysis of squeezing-induced hybrid nanofluid flow in Darcy-Forchheimer porous medium

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 193-208页

作者： K.mUHAmmAD m.SARFRAZ Department of Humanities and Sciences School of Electrical Engineering and Computer Science National University of Sciences and Technology Department of mathematics Quaid-i-Azam University

This article presents a mathematical model addressing a scenario involving a hybrid nanofluid flow between two infinite parallel plates. One plate remains stationary, while the other moves downward at a squeezing velocity. The space between these plates contains a Darcy-Forchheimer porous medium. A mixture of water-based fluid with gold(Au) and silicon dioxide(Si O2) nanoparticles is formulated. In contrast to the conventional Fourier's heat flux equation, this study employs the Cattaneo-Christov heat flux equation. A uniform magnetic field is applied perpendicular to the flow direction, invoking magnetohydrodynamic(mHD) effects. Further, the model accounts for Joule heating, which is the heat generated when an electric current passes through the fluid. The problem is solved via NDSolve in mATHEmATICA. Numerical and statistical analyses are conducted to provide insights into the behavior of the nanomaterials between the parallel plates with respect to the flow, energy transport, and skin *** findings of this study have potential applications in enhancing cooling systems and optimizing thermal management strategies. It is observed that the squeezing motion generates additional pressure gradients within the fluid, which enhances the flow rate but reduces the frictional drag. Consequently, the fluid is pushed more vigorously between the plates, increasing the flow velocity. As the fluid experiences higher flow rates due to the increased squeezing effect, it spends less time in the region between the plates. The thermal relaxation, however, abruptly changes the temperature, leading to a decrease in the temperature fluctuations.

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Position-sensitive detectors based on two-dimensional materials

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Nano Research 2021年第6期14卷 1889-1900页

作者： Wenhui Wang Junpeng Lu Zhenhua ni School of Physics and Key Laboratory of mEmS of the ministry of Education Southeast UniversityNanjing211189China

Two-dimensional(2D)materials have attracted great attention in optoelectronics because of their unique structure,optical and electrical *** high-performance photodetectors and implementing their applications are eager to promote the development of 2D ***-sensitive detector(PSD)is an optical inspection device for the precise measurements of position,distance,angle,and other relevant physical *** is a widely used component in the fields of tracking,aerospace,nanorobotics,and so ***,PSD is also a photodetector based on the lateral photovoltaic effect(LPE).This article reviews recent progress in high-performance PSD based on 2D *** high-sensitive photodetectors and LPE involved in 2D photodetectors are firstly ***,we introduce the research progress of PSD based on 2D materials and analyze the carrier dynamics in different device ***,we summarize the functionalities and applications of PSD based on 2D materials,and highlight the challenges and opportunities in this research area.

关键词： two-dimensional(2D)materials graphene photodetector lateral photovoltaic effect position-sensitive detector heterojunction

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Search for microglia-specific peptides:advances in the discovery toolbox

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Neural Regeneration Research 2025年第2期20卷 471-472页

作者： Ivan Sarabia Kyle m.Koss Department of Surgery University of ArizonaTucsonAZUSA

Uncontrolled and chronic inflammatory states in the central nervous system(CNS)are the hallmark of neurodegenerative pathology and every injury or stroke-related *** key mediators of these neuroinflammatory states are glial cells known as microglia,the resident immune cell at the core of the inflammatory event,and astroglia,which encapsulate inflammatory insults in proteoglycan-rich scar *** gliotic scar blocks significant portions of healthy axonal networking,preventing *** most neuroinflammation is exclusively based on the responses of said microglia,their phenotypes are suggested to follow those of macrophages;m1 and m2 are opposites of pro-and ***,microglial phenotypes have been identified to be on an inflammatory spectrum encompassing developmental,homeostatic,and reparative behaviors as opposed to their ability to affect devastating cell death cascades and scar tissue formation.

关键词： inflammation pathology death

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multi-physical modeling and Adjusting for Ultrasonic Assisted Soft Abrasive Flow Processing

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Chinese Journal of mechanical Engineering 2023年第4期36卷 111-124页

作者： Yesha ni Yunfeng Tan Dapeng Tan Key Lab of E&m Ministry of Education and Zhejiang ProvinceZhejiang University of TechnologyHangzhou 310014China Collaborative Innovation Center of High-end Laser manufacturing Equipment Zhejiang Province&Ministry of EducationHangzhou 310014China

The polishing efficiency of the soft abrasive flow(SAF)method is low,which is not in line with the concept of carbon emission reduction in industrial *** address the above issue,a two-phase fluid multi-physics modeling method for ultrasonic-assisted SAF processing is *** acoustics-fluid coupling mechanic model based on the realizable k-ε model and Helmholtz equation is built to analyze the cavitation *** results show that the pro-posed modeling and solution method oriented to ultrasonic-assisted SAF processing have better revealed the flow field evolution *** turbulence kinetic energy at different ultrasonic frequencies and amplitudes is *** results show that the ultrasonic vibration can induce a cavitation effect in the constrained flow chan-nel and promote the turbulence intensity and uniformity of the abrasive flow.A set of comparative polishing experiments with or without ultrasonic vibration are conducted to explore the performance of the proposed *** can be found that the ultrasonic-assisted SAF method can improve the machining efficiency and uniformity,to achieve the purpose of carbon emission *** relevant result can offer a helpful reference for the SAF method.

关键词： Soft abrasive flow Ultrasonic vibration Cavitation effect Polishing efficiency Turbulent kinetic energy

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STEP-LIKE CONTRAST STRUCTURE OF SINGULARLY PERTURBED OPTImAL CONTROL PROBLEm＊

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Journal of Computational mathematics 2012年第1期30卷 2-13页

作者： mingkang ni Limeng Wu Department of mathematics East China Normal UniversityShanghai 200241China

The existence of step-like contrast structure for a class of singularly perturbed optimal control problem is presented by contrast structure theory. By means of direct scheme of boundary function method, we construct the uniformly valid asymptotic solution for the singularly perturbed optimal control problem. As an application, an example is given to illustrate the main result in this paper.

关键词： Singular perturbation Optimal control problem Contrast structure.

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Interval design point method for calculating the reliability of structural systems

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Science China(Physics,mechanics & Astronomy) 2013年第11期56卷 2151-2161页

作者： ni Zao QIU ZhiPing Shanghai Aircraft Design and Research institute COMAC Institute of Solid mechanics Beijing University of Aeronautics and Astronautics

The evaluation of reliability for structural system is important in engineering *** this paper,by combining the design point method,JC method,interval analysis theory,and increment load method,we propose a new interval design point method for the reliability of structural systems in which the distribution parameters of random variables are described as interval *** proposed method may provide exact probabilistic interval reliability of structures whose random variables can have either a normal or abnormal distribution *** last,we show the feasibility of the proposed approach through a typical example.

关键词： probability design point method interval analysis probabilistic interval reliability parameters uncertainty

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The Cotorsion Pair Cogenerated by the Subcategory of Stable Functors in ((R-mod)^op, Ab)

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Algebra Colloquium 2019年第2期26卷 259-270页

作者： Xianhui Fu meiyuan ni School of mathematics and Statistics Northeast Normal University Changchun 130024 China

Let R be an associative ring with identity. Denote by ((R-mod)^op, Ab) the category consisting of contravariant functors from the category of finitely presented left R-modules R-mod to the category of abelian groups Ab. An object in ((R-mod)^op, Ab) is said to be a stable functor if it vanishes on the regular module R. Let T be the subcategory of stable functors. There are two torsion pairs t1=(Gen(-,R),T)and t2=(T,F1), where 1 is the subcategory of ((R-mod)^op, Ab) consisting of functors with flat dimension at most 1. In this article, let R be a ring of weakly global dimension at most 1, and assume R satisfies that for any exact sequence 0 → m → N → K → 0, if m and N are pure injective, then K is also pure injective. We calculate the cotorsion pair (⊥T,(⊥T)⊥)cogenerated by T clearly. It is shown that G∈⊥T if and only if G/t1(G) is a projective object in T, i.e., G/t1(G)=(-,m) for some R-module m;and G∈(⊥T)⊥ if and only if G/t2(G) is of the form (-, E), where E is an injective R-module.

关键词： stable functors cotorsion pairs torsion pairs

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Ultra-thin, planar, Babinet-inverted plasmonic metalenses

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Light(Science & Applications) 2013年第1期2卷 170-175页

作者： Xingjie ni Satoshi Ishii Alexander V Kildishev Vladimir m Shalaev School of Electrical and Computer Engineering and Birck Nanotechnology Center Purdue UniversityWest LafayetteIN 47907USA

We experimentally demonstrate the focusing of visible light with ultra-thin,planar metasurfaces made of concentrically perforated,30-nm-thick gold *** perforated nano-voids—Babinet-inverted(complementary)nano-antennas—create discrete phase shifts and form a desired wavefront of cross-polarized,scattered *** signal-to-noise ratio in our complementary nano-antenna design is at least one order of magnitude higher than in previous metallic nano-antenna *** first study our proof-of-concept‘metalens’with extremely strong focusing ability:focusing at a distance of only 2.5 mm is achieved experimentally with a 4-mm-diameter lens for light at a wavelength of 676 *** then extend our work with one of these‘metalenses’and achieve a wavelength-controllable focal *** characterization of the lens confirms that switching the incident wavelength from 676 to 476 nm changes the focal length from 7 to 10 mm,which opens up new opportunities for tuning and spatially separating light at different wavelengths within small,micrometer-scale *** the proposed designs can be embedded on-chip or at the end of an optical *** designs also all work for two orthogonal,linear polarizations of incident light.

关键词： metalens nano-antennas plasmonics wavefront shaping

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NUmERICAL　SImULATION　OF　THE　TURBULENT　FLUID　FLOW　AND　PREDICTION　OF　INCIPIENT　CAVITATION　NUmBER　ON　ISOLATED　SURFACE　TRIANGULAR　PROTRUSION

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Journal of Hydrodynamics 1996年第1期8卷 67-75页

作者： Ren, Bing ni, Hangen Dalian Univ of Technology Dalian China

For any type of 2-dimensional flowing field, this paper has developed a very effective numerical technique in generating orthogonal computation grids, which shows a wide promise especially for microscale arbitrary shapes concerned. In simulating high speed flowing, it has been verified that Dynamic SGS model is a reliable tool available to engineers, especially in predicting inhomogeneous turbulence nowing. On the basis of physical and numerical methods, this paper has presented, respectively, experimental expression and numerical results for incipient cavitation number. For velocity no more than 15m/s, it was verified that the value of incipient cavitation number from the two different sources approximately coincided with each other.

关键词： numerical simulations turbulence model incipient cavitation

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