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Effect of Poly（ethylene glycol）-400 and Carbon on MoOz Nanocomposite Materials and Its Catalytic Activity for Biginelli reactions

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Chinese Journal of Chemistry 2011年第10期29卷 2049-2056页

作者： Navgire, Madhukar Yelwande, Ajeet arbad, balasaheb Lande, Machhindra Department of Chemistry Dr. Babasaheb Ambedkar Marathwada University Aurangabad 431004 India

The effect of addition of poly（ethylene glycol）-400 （PEG-400） and carbon （0, 1, 2 and 3 wt%） as substrates were investigated systematically to get the desired phase of carbon-doped MoO3 material. The carbon source was prepared from the Acacia arabica plant wood. The resulting samples were calcined at 500 ℃. The effect of PEG-400 and carbon composite on the structure, particle size and morphology were investigated. The prepared samples were characterized by XrD, SEM-EDS and FT-Ir techniques. The samples with PEG-400 and carbon ad- dition give better control of particle size and porosity. The prepared catalysts were tested for the synthesis of 3,4-dihydropyrimidones via the Biginelli-type condensation reaction. This new method consistently has the advan- tage of excellent yields （88%--93%） and short reaction times （1.5--3 h） than do classical Biginelli reaction conditions.

关键词： carbon substrate MOO3 PEG Biginelli reaction 3,4-dihydropyrimidones

A recyclable and Highly Effective ZnO-beta Zeolite as a Catalyst for One-pot Three-Component Synthesis of Tetrahydrobenzo[b]pyrans

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Chinese Journal of Chemistry 2011年第1期29卷 199-202页

作者： Katkar, Santosh Shriram Lande, Machhindra Karbhari arbad, balasaheb ramrao Gaikwad, Suresh Tukaram Department of Chemistry Dr. Babasaheb Ambedkar Marathwada University Aurangabad-431004 Maharashtra India

4H-Benzo[b]pyrans was synthesized under reflux condition in ethanol via condensation of benzaldehyde, malononitrile and dimedone with ZnO-beta zeolite as an inexpensive and effective catalyst. The key features of the reported protocols are good to excellent yields, short reaction time and recovery and reusability of catalytic material.

关键词： heterogeneous 4H-benzo[b]pyrans ZnO-beta zeolite multicomponent cyclocondensation

纳米Ce_1Mg_xZr_(1-x)O_2固体多相催化剂的制备、表征及催化合成四氢苯并[b]吡喃衍生物的性能(英文)

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催化学报 2010年第6期31卷 631-636页

作者： Sandip rATHOD balasaheb arbad Machhindra LANDE Department of Chemistry Dr.Babasaheb Ambedkar Marathwada University

A series of Ce1MgxZr1-xO2 mixed metal oxides with different molar ratios were prepared by simple co-precipitation and were characterized by X-ray diffraction,infrared spectroscopy,scanning electron microscopy,energy dispersive spectroscopy,temperature-programmed desorption of CO2,and N2 adsorption *** prepared materials were tested for catalytic activity by the synthesis of tetrahydrobenzo[b]pyran derivatives using a three component reaction(aromatic aldehydes,malononitrile,and dimedone) in an ethanol *** best catalytic activity was obtained with *** particle size or crystallite size was estimated using the Debye-Scherrer *** addition of magnesium oxide into the ceria-zirconia lattice resulted in the formation of nanosized particles ranging from 5.41 to 9.78 *** work describes the catalytic behavior of magnesium oxide in mixed metal oxide systems.

关键词： Ce1MgxZr1-xO2 镁氧化物一起沉淀 nanosized 材料 tetrahydrobenzo [b ] pyran

MoO_3-TiO_2纳米晶体复合材料光降解糖蜜(英文)

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催化学报 2012年第2期33卷 261-266页

作者： Madhukar NAVGIrE Ajeet YELWANDE Deepak TAYDE balasaheb arbad Machhindra LANDE Department of Chemistry Dr.Babasaheb Ambedkar Marathwada University

A MoO3-TiO2 nanocrystalline composite material was prepared by a simple solgel *** synthesized material was charac-terized by X-ray diffraction,scanning electron microscopy with an electron dispersion spectroscopy,transmission electron microscopy,and Fourier transform infrared *** is a dark brown pigment found in wastewater from the sugar industry and it pollutes *** polluted water is generally referred to as molasses and it undergoes fermentation and is solely responsible for water,soil,and air *** synthesized catalytic material was found to be effective in degrading molasses under UV-visible *** of treated and untreated molasses was carried out by measuring its color,chemical oxygen demand,biological oxygen demand,pH,and total dissolved *** from these analyses indicate the effective photodegradation of the *** methodology has several advantages such as high photocatalytic activity,non-toxicity,cleanliness,and reusability of the catalytic material.

关键词： sol-gel molybdenum oxide titanium oxide photodegradation molasses pollution control

Analysis and Optimization of Operational and Pollutant Attributes of Diesel Engine with CNT-Infused Orange Peel Biodiesel-Diesel Blend Fuel

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Journal of Thermal Science 2024年第2期33卷 761-778页

作者： ranjeet rAI r.r.SAHOO Mechanical Engineering Department GLA UniversityMathura281406India Mechanical Engineering Department IIT(BHU)Varanasi221005India

The current study is performed to find sustainable solutions for the future of transportation and environmental *** conventional methods and experimental design table(L16 Orthogonal Array)techniques have been employed to examine and optimize a diesel-powered engine's operational and pollutant *** L16 Orthogonal Array is obtained through Taguchi's experimental design approach using Minitab 16 *** experimental design incorporated three control variables,namely engine speed,fuel type,and engine load,each with four *** operational parameters,namely brake thermal efficiency(BTE)and brake specific fuel consumption(BSFC),as well as the emission characteristics,including hydrocarbon(HC),carbon monoxide(CO),nitrogen oxide(NO),and smoke emissions,were acquired using the L16 orthogonal array(OA) and subsequently *** utilization of methodologies such as signal-to-noise(S/N) ratio and grey analysis was employed to determine the optimal operational state of the engine to achieve maximum performance while minimizing *** engine's ideal state of operation,in terms of BTE and BSFC,was determined to be at 75% engine load,1000 r/min engine speed,and using 10^(-4)(in vol) carbon nanotube incorporated 20% orange peel biodiesel(OPB20CNT100) blended fuel(A3-B1-C4).The study indicated that engine load significantly influenced BTE and BSFC,with 84.05% and 87.79% contribution factors,*** 25% engine load,1000 r/min,and OPB20CNT100 fuel(A1-B1-C4) CO,smoke,NO,and HC emissions were the *** load affects emissions the *** BSFC increased 3.10% and NO emissions 1.77%.BTE,CO,smoke,and HC emissions decreased by 1.9%,12.29%,47.05%,and 47.22%,respectively,at optimal operating conditions concerning diesel *** study shows that Taguchi-Grey's experimental design optimizes diesel engine operational and pollutant *** outcomes revealed that orange peel biodiesel infused with CNT can replace diesel fuel in a

关键词： Taguchi-Grey method OPB20CNT100 transesterification S/N ratio GrG HC CO and NO

Multidimensional images and aberrations in STEM

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Chinese Physics B 2024年第9期33卷 68-74页

作者： Eric r.Hoglund Andrew r.Lupini Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831United States

recent advances in scanning transmission electron microscopy(STEM)have led to increased development of multidimensional STEM imaging modalities and novel image reconstruction *** interest arises because the main electron lens in a modern transmission electron microscope usually has a diffraction-space information limit that is significantly better than the real-space resolution of the same *** state-of-affairs is sometimes shared by other scattering methods in modern physics and contributes to a broader excitement surrounding multidimensional techniques that scan a probe while recording diffraction-space images,such as ptychography and scanning nano-beam ***,the contrasting resolution in the two spaces raises the question as to what is limiting their effective ***,we examine this paradox by considering the effects of aberrations in both image and diffraction planes,and likewise separate the contributions of pre-and post-sample *** consideration provides insight into aberration-measurement techniques and might also indicate improvements for super-resolution techniques.

关键词： scanning transmission electron microscopy (STEM) aberrations

Kinematic analysis of flexible bipedal robotic systems

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 795-818页

作者： r.FAZEL A.M.SHAFEI S.r.NEKOO Department of Mechanical Engineering Shahid Bahonar University of KermanKerman ***Iran Departamento de Ingenieria de Sistemas y Automatica Escuela Técnica Superior de IngenieriaUniversidad de SevillaSeville 41092Spain

In spite of its intrinsic complexities,the passive gait of bipedal robots on a sloping ramp is a subject of interest for numerous *** distinguishes the present research from similar works is the consideration of flexibility in the constituent links of this type of robotic *** is not a far-fetched assumption because in the transient(impact)phase,due to the impulsive forces which are applied to the system,the likelihood of exciting the vibration modes increases ***,the human leg bones that are involved in walking are supported by viscoelastic muscles and ***,for achieving more exact results,it is essential to model the robot links with viscoelastic *** this end,the Gibbs-Appell formulation and Newton's kinematic impact law are used to derive the most general form of the system's dynamic equations in the swing and transient phases of *** most important issue in the passive walking motion of bipedal robots is the determination of the initial robot configuration with which the system could accomplish a periodic and stable gait solely under the effect of gravitational *** extremely unstable nature of the system studied in this paper and the vibrations caused by the impulsive forces induced by the impact of robot feet with the inclined surface are some of the very serious challenges encountered for achieving the above-mentioned *** overcome such challenges,an innovative method that uses a combination of the linearized equations of motion in the swing phase and the algebraic motion equations in the transition phase is presented in this paper to obtain an eigenvalue *** solving this problem,the suitable initial conditions that are necessary for the passive gait of this bipedal robot on a sloping surface are *** effects of the characteristic parameters of elastic links including the modulus of elasticity and the Kelvin-Voigt coefficient on the walking stability of this type of

关键词： bipedal robot flexible link swing phase transient phase eigenvalue problem Kelvin-Voigt coefficient

Holographic dark energy in non-conserved gravity theory

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Communications in Theoretical Physics 2024年第4期76卷 126-133页

作者： H r Fazlollahi Institute of Gravitation and Cosmology Peoples Friendship University of Russia(RUDN University)6 Miklukho-Maklaya StMoscow117198Russia

recently, reconsidering the rastall idea T_(μ;νν)^(v)=α_(,μ) through relativistic thermodynamics gives a new form for the scalar field α which led us to construct modern modified theory of gravity debugged ‘non-conserved gravity theory’ Fazlollahi 2023 Euro. Phys. J. C 83 923. This theory unlike other modified theories of gravity cannot directly explain the current acceleration expansion in the absence of the cosmological constant and or existence of other forms of dark energy. Hence, in this study we have reinvestigated holographic dark energy Ρ_(X)~H^(2) in the non-conserved theory of gravity. In this context, the density and pressure of dark energy depend on the non-conserved term and density of the dust matter field. As shown, due to non-conservation effects on large-scale structures, unlike the original holographic model, our model onsets an acceleration epoch for the current Universe satisfies observations. Moreover, the interaction and viscous scenarios are studied for this model.

关键词： non-conserved gravity covariant form of thermodynamics holographic dark energy

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： r Gharaei E Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations