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Structural synthesis of ancient Chinese foot-operated silk-reeling mechanism

Kuohung HSIAO, Yuhsun CHEN, Hongsen YAN,

《机械工程前沿（英文）》 2010年 第5卷 第3期   页码 279-288 doi: 10.1007/s11465-010-0101-2

摘要： This work synthesizes the structures of the foot-operated silk-reeling mechanism, which was vaguely depicted in many literatures in ancient China. Based on the analysis of the mechanism, the structural characteristics and design constraints of the mechanism with indeterminate links and joints are concluded. Then, according to the concepts of generalization and specialization subject to the concluded design constraints, all feasible structures of the mechanism that met the technological standards of the subject’s time period are reconstructed. This reconstruction process provides a logical foundation to better understanding, clarification, and suggestions for the issue of ancient mechanical drawings with indeterminate links and joints.

关键词： silk-reeling mechanism     structure of mechanism     reconstruction design     history of machinery    

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Design and analysis of the gripper mechanism based on generalized parallel mechanisms with configurable

《机械工程前沿（英文）》 2021年 第16卷 第4期   页码 765-781 doi: 10.1007/s11465-021-0655-1

摘要： Generalized parallel mechanisms with a configurable moving platform have become popular in the research field of parallel mechanism. This type of gripper mechanism can be applied to grasp large or heavy objects in different environments that are dangerous and complex for humans. This study proposes a family of novel (5 + 1) degrees of freedom (three translations and two rotations plus an additional grasping motion) gripper mechanisms based on the generalized parallel mechanisms with a configurable moving platform. First, the configurable moving platform, which is a closed loop, is designed for grasping manipulation. The hybrid topological arrangement is determined to improve the stiffness of the manipulator and realize high load-to-weight ratios. A sufficient rule based on Lie group theory is proposed to synthesize the mechanism. The hybrid limb structure is also enumerated. A family of novel gripper mechanisms can be assembled through the hybrid limbs by satisfying the rule. Two examples of the gripper mechanisms with and without parallelogram pairs are shown in this study. A kinematic analysis of the example mechanism is presented. The workspace shows that the mechanism possesses high rotational capability. In addition, a stiffness analysis is performed.

关键词： generalized parallel mechanism     configurable moving platform     gripper mechanism     type synthesis     kinematic analysis    

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VITHM1 mediated green synthesis of silver nanoparticles: Mechanism and biological applications

Mani Abirami, Krishnan Kannabiran

《化学科学与工程前沿（英文）》 2016年 第10卷 第4期   页码 542-551 doi: 10.1007/s11705-016-1599-6

摘要： We present the microbial green synthesis of silver nanoparticles (NPs) by VITHM1 strain (MTCC No. 12465). The secondary metabolites in the cell free supernatant of this bacterium when incubated with 1 mmol/L AgNO , mediated the biological synthesis of AgNPs. The synthesized AgNPs were characterized by UV-visible spectrum, X-ray diffraction (XRD), atomic force microscope, scanning electron microscopy equipped with energy dispersive spectroscopy, transmission electron microscopy, FT-IR spectroscopy, dynamic light scattering and zeta potential. They were highly stable and, spherical in shape with the average size of 30?50 nm. The secondary metabolites involved in the formation of AgNPs were identified gas chromatography-mass spectrography. The 3D structure of the unit cell of the synthesized AgNPs was determined using XRD data base. The synthesized AgNPs exhibited significant antibacterial activity against tested bacterial pathogens, and did not show haemolysis on human red blood cells. This green synthesis could provide a new platform to explore and use AgNPs as antibacterial therapeutic agents.

关键词： Streptomyces ghanaensis VITHM1     nanoparticles     3D structure     antibacterial activity    

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Design of a novel side-mounted leg mechanism with high flexibility for a multi-mission quadruped earth

《机械工程前沿（英文）》 2023年 第18卷 第2期 doi: 10.1007/s11465-022-0740-0

摘要： Earth rover is a class of emerging wheeled-leg robots for nature exploration. At present, few methods for these robots’ leg design utilize a side-mounted spatial parallel mechanism. Thus, this paper presents a complete design process of a novel 5-degree-of-freedom (5-DOF) hybrid leg mechanism for our quadruped earth rover BJTUBOT. First, a general approach is proposed for constructing the novel leg mechanism. Subsequently, by evaluating the basic locomotion task (LT) of the rover based on screw theory, we determine the desired motion characteristic of the side-mounted leg and carry out its two feasible configurations. With regard to the synthesis method of the parallel mechanism, a family of concise hybrid leg mechanisms using the 6-DOF limbs and an L1F1C limb (which can provide a constraint force and a couple) is designed. In verifying the motion characteristics of this kind of leg, we select a typical (3-UPRU&RRRR)&R mechanism and then analyze its kinematic model, singularities, velocity mapping, workspace, dexterity, statics, and kinetostatic performance. Furthermore, the virtual quadruped rover equipped with this innovative leg mechanism is built. Various basic and specific LTs of the rover are demonstrated by simulation, which indicates that the flexibility of the legs can help the rover achieve multitasking.

关键词： design synthesis     parallel mechanism     hybrid leg mechanism     screw theory     quadruped robot    

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Seed-induced synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms

Zhaoqi Ye, Hongbin Zhang, Yahong Zhang, Yi Tang

《化学科学与工程前沿（英文）》 2020年 第14卷 第2期   页码 143-158 doi: 10.1007/s11705-019-1852-x

摘要： As an important zeolite material, MFI zeolites, as well as their controllable synthesis, are of great interest in both basic and applied science. Among the developed synthetic approaches, the seed-induced method has gradually evolved into a facile, low-cost, and even green alternative to give zeolites the desirable physicochemical properties. In this review, we briefly summarize the development of seed-induced syntheses of diverse functional MFI zeolites, where the “living” seed crystals not only direct the formation of zeolitic framework but also function as special “templates” or “units” to fine-tune the zeolite materials with diverse sizes, shapes, compositions, morphologies and pore structures. Moreover, on the basis of their structural features and crystallization behaviors in seed-induced synthesis, we reveal the roles of seeds and discuss the related crystallization mechanisms including both classical and non-classical pathways. We also want to guide readers to investigate the structure-performance relationships between these functional MFI zeolite catalysts and suitable catalytic reactions.

关键词： seed-induced synthesis     MFI zeolite     synthesis mechanism     catalytic property    

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Facile synthesis of polyaniline nanorods to simultaneously enhance the mechanical properties and wear

《化学科学与工程前沿（英文）》 2023年 第17卷 第9期   页码 1254-1266 doi: 10.1007/s11705-023-2297-3

摘要： To enhance the mechanical properties and wear resistance of epoxy resin, polyaniline nanorods were first synthesized using a facile route, and then introduced into the epoxy matrix to yield composites via solution mixing. Several measurements were conducted to investigate the phase structures and compositions of polyaniline nanorods, and their positive influences on the mechanical and tribological properties of epoxy resin were also characterized. The results confirmed that the as-synthesized polyaniline exhibited representative rod-like morphologies and dispersed well in the epoxy matrix, leading to significant enhancements in the tensile strength and elastic modulus of epoxy composites. The highest values of 110.33 MPa and 2.04 GPa were obtained by adding 5%–7% polyaniline nanorods, which were 43% and 62% higher than the pure sample, respectively. The wear rate was increased first and then decreased along with polyaniline nanorods, presenting the lowest value of 2.12 × 10−5 mm3·Nm–1 by adding 5% filler, which was markedly reduced by ca. 70% compared to the control sample. Finally, the possible wear mechanism was proposed and discussed in detail. This study tried to broaden the applications of polyaniline nanorods in the field of tribology.

关键词： epoxy resin     polyaniline nanorods     mechanical property     tribological performance     wear mechanism    

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Automated synthesis of steady-state continuous processes using reinforcement learning

《化学科学与工程前沿（英文）》 2022年 第16卷 第2期   页码 288-302 doi: 10.1007/s11705-021-2055-9

摘要： Automated flowsheet synthesis is an important field in computer-aided process engineering. The present work demonstrates how reinforcement learning can be used for automated flowsheet synthesis without any heuristics or prior knowledge of conceptual design. The environment consists of a steady-state flowsheet simulator that contains all physical knowledge. An agent is trained to take discrete actions and sequentially build up flowsheets that solve a given process problem. A novel method named SynGameZero is developed to ensure good exploration schemes in the complex problem. Therein, flowsheet synthesis is modelled as a game of two competing players. The agent plays this game against itself during training and consists of an artificial neural network and a tree search for forward planning. The method is applied successfully to a reaction-distillation process in a quaternary system.

关键词： automated process synthesis     flowsheet synthesis     artificial intelligence     machine learning     reinforcement learning    

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Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 372-375 doi: 10.1007/s11705-010-0570-1

摘要： Calcium carbide was successfully synthesized by carbothermal reduction of lime with coke at 1973 K for 1.5 h. The effect of potassium carbonate as additive on the composition and morphology of the product was investigated using X-ray diffraction and scanning electron microscope. Addition of potassium carbonate increased the yield of calcium carbide. The sample in the presence of potassium carbonate generated acetylene gas of 168.3 L/kg, which was 10% higher than that in the absence of potassium carbonate. This result confirmed the catalytic effect of potassium carbonate on the synthesis of calcium carbide. A possible mechanism of the above effects was that the additive, which was melted at the reduction temperature, dissolved CaO and so promoted the contact between CaO and carbon, which was essential for the solid-solid reaction to form calcium carbide.

关键词： calcium carbide     synthesis     catalysis    

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Study on a green synthesis of

Aixin WANG, Yuanbin SHE, Jing FAN

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 219-221 doi: 10.1007/s11705-009-0058-z

摘要： A novel method for the synthesis of -oxo-bis[tetraarylporphyrinatoiron] ([TRPPFe] O) based on the reaction between tetraarylporphyrinironchloride (TRPPFeCl) and H O in toluene was investigated in this paper. Three kinds of [TRPPFe] O were synthesized by this novel synthetic method, and their structures were characterized by elemental analysis, IR spectra and UV-Vis spectroscopy.

关键词： μ-oxo-bis[tetraarylphenylporphinatoiron]     green synthesis     water    

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Advantageous mechanochemical synthesis of copper(I) selenide semiconductor, characterization, and properties

《化学科学与工程前沿（英文）》 2022年 第16卷 第3期   页码 433-442 doi: 10.1007/s11705-021-2066-6

摘要： Copper(I) selenide-nanocrystalline semiconductor was synthesized via one-step mechanochemical synthesis after 5 min milling in a planetary ball mill. The kinetics of synthesis was followed by X-ray powder diffraction analysis and specific surface area measurements of milled 2Cu/Se mixtures. The X-ray diffraction confirmed the orthorhombic crystal structure of Cu2Se with the crystallite size ~25 nm. The surface chemical structure was studied by X-ray photoelectron spectroscopy, whereby the binding energy of the Cu 2p and Se 3d signals corresponded to Cu+ and Se2– oxidation states. Transmission electron microscopy revealed agglomerated nanocrystals and confirmed their orthorhombic structure, as well. The optical properties were studied utilizing ultraviolet-visible spectroscopy and photoluminescence spectroscopy. The direct bandgap energy 3.7 eV indicated a blue-shift phenomenon due to the quantum size effect. This type of Cu2Se synthesis can be easily adapted to production dimensions using an industrial vibratory mill. The advantages of mechanochemical synthesis represent the potential for inexpensive, environmentally-friendly, and waste-free manufacturing of Cu2Se.

关键词： Cu2Se     berzelianite     nanocrystalline semiconductor     mechanochemical synthesis     planetary ball mill    

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Biomass to dimethyl ether by gasification/synthesis technology

Tiejun WANG, Yuping LI, Longlong MA, Chuangzhi WU

《能源前沿（英文）》 2011年 第5卷 第3期   页码 330-339 doi: 10.1007/s11708-010-0121-y

摘要： Technical and economic analysis was done for the biomass to dimethyl ether (DME) technology to promote the gasification/synthesis route for biofuel production and its application as a fossil fuel substitute. The technology of biomass gasification/synthesis has obvious advantages, including production flexibility, environmental friendliness, economic feasibility, and application versatility. Biomass gasification/synthesis technology integrates bio-DME synthesis, fertilizer production, electricity generation, and waste heat utilization to convert waste biomass residues to DME for use as liquid petroleum gas, transportation fuel substitute, and chemical intermediates, which has been proven to be one of the most effective and clean biomass utilization routes. The 1000 t/a-scale demonstration plant has a bio-DME production rate of 6 to 7 / , biomass gasification efficiency of≥82%, once-through CO conversion of ≥70%, DME selectivity (DME/DME+other organic products) of ≥90%, and a total system efficiency of ≥38%. The demonstration plant also has self-sufficient steam and electricity supply. The 10,000tons/a-scale bio-DME production cost with or without feedstock subsidy is estimated to be 1968 Yuan/t and 2868 Yuan/t, respectively in China. Because of the limitation in biomass feedstock collection cost, massive and disperse commercial plants with a capacity of 10000 t/a bio-DME are more suitable for rural areas.

关键词： technical and economic analysis     biomass     dimethyl ether     gasification/synthesis    

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Multi-resolution texture synthesis from turntable image sequences

Xuedong WANG, Xiaojun WU, Xiaorong ZHANG

《机械工程前沿（英文）》 2012年 第7卷 第1期   页码 72-80 doi: 10.1007/s11465-012-0305-8

摘要：

Texture synthesis and texture mapping are important technologies for rendering realistic three-dimensional scene. It has been widely used in virtual reality, urban modeling, 3D animation, gaming and other areas. In this paper, we propose a fast method to construct high quality texture map for multi-resolution texture synthesis from turntable image sequences. Given a 3D mesh model, we first get the projection relationship between 3D mesh and image sequences. We then use image sequences to construct a texture triangle for each 3D triangle mesh and get a global rectangular texture map for the whole mesh. Another approach to construct a texture map is using Stretch-minimizing mesh parameterization. Finally, we map the texture to mesh model to verify the quality of these two methods. The high performance of this method has been demonstrated in many real object models.

关键词： texture synthesis     multi-resolution     texture map     texture mapping    

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Kinematical synthesis of an inversion of the double linked fourbar for morphing wing applications

J. AGUIRREBEITIA, R. AVILéS, I. FERNáNDEZ, M. ABASOLO

《机械工程前沿（英文）》 2013年 第8卷 第1期   页码 17-32 doi: 10.1007/s11465-013-0364-5

摘要：

This paper presents the kinematical features of an inversion of the double linked fourbar for morphing wing purposes. The structure of the mechanism is obtained using structural synthesis concepts, from an initial conceptual schematic. Then, kinematic characteristics as instant center of rotation, lock positions, dead point positions and uncertainty positions are derived for this mechanism in order to face the last step, the dimensional synthesis; in this sense, two kinds of dimensional synthesis are arranged to guide the wing along two positions, and to fulfill with the second one some aerodynamic and minimum actuation energy related issues.

关键词： morphing wing     structural synthesis     dimensional synthesis     geometrical kinematics    

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Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

Rekha M., H. Kathyayini, N. Nagaraju

《化学科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 415-421 doi: 10.1007/s11705-013-1360-3

摘要： Two catalysts, alumina and manganese oxide supported on alumina, have been prepared by calcination and precipitation-impregnation methods, respectively. The catalysts are characterised by the following techniques: Brunner-Emmett-Teller-N adsorption-desorption for surface area, temperature programmed desorption of NH and -butyl amine back titration methods for surface acidity, powder X-ray diffraction for textural properties, and Fourier transform infrared spectroscopy for the anionic radicals. The catalytic activity has been determined under heterogeneous conditions in the condensation reaction between -phenylenediamine and benzil. The product purity is checked by thin-layer chromatography and melting point. The products are also analysed by LC-MS and H-NMR techniques. The yields of the products have been found to be good and catalysts exhibited excellent recyclability. The effect of changing the reaction parameters such as temperature, reaction time, amount of the catalyst, nature of solvent and molar ratio of reactants on the yield of the product has been studied. The surface acidity of the catalysts plays an important role in activating the reaction.

关键词： alumina     manganese oxide deposited on alumina     quinoxaline synthesis    

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dehydrogenation reaction on high-performance PdAu alloy nanoparticles prepared by the eco-friendly slow synthesis

《能源前沿（英文）》   页码 751-762 doi: 10.1007/s11708-023-0895-3

摘要： Dehydrogenation of formic acid (FA) is considered to be an effective solution for efficient storage and transport of hydrogen. For decades, highly effective catalysts for this purpose have been widely investigated, but numerous challenges remain. Herein, the PdxAu1−x (x = 0, 0.2, 0.4, 0.5, 0.6, 0.8, 1) alloys over the whole composition range were successfully prepared and used to catalyze FA hydrogen production efficiently near room temperature. Small PdAu nanoparticles (5–10 nm) were well-dispersed and supported on the activated carbon to form PdAu solid solution alloys via the eco-friendly slow synthesis methodology. The physicochemical properties of the PdAu alloys were comprehensively studied by utilizing various measurement methods, such as X-ray diffraction (XRD), N2 adsorption–desorption, high angle annular dark field-scanning transmission electron microscope (HAADF-STEM), X-ray photoelectrons spectroscopy (XPS). Notably, owing to the strong metal-support interaction (SMSI) and electron transfer between active metal Au and Pd, the Pd0.5Au0.5 obtained exhibits a turnover frequency (TOF) value of up to 1648 h−1 (313 K, nPd+Au/nFA = 0.01, nHCOOH/nHCOONa = 1:3) with a high activity, selectivity, and reusability in the FA dehydrogenation.

关键词： FA dehydrogenation     face-centred cubic structures     PdAu solid solution alloy nanoparticles     slow synthesis methodology     SMSI effect    

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标题 作者 时间 类型 操作

Structural synthesis of ancient Chinese foot-operated silk-reeling mechanism

Kuohung HSIAO, Yuhsun CHEN, Hongsen YAN,

期刊论文

Design and analysis of the gripper mechanism based on generalized parallel mechanisms with configurable

期刊论文

VITHM1 mediated green synthesis of silver nanoparticles: Mechanism and biological applications

Mani Abirami, Krishnan Kannabiran

期刊论文

Design of a novel side-mounted leg mechanism with high flexibility for a multi-mission quadruped earth

期刊论文

Seed-induced synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms

Zhaoqi Ye, Hongbin Zhang, Yahong Zhang, Yi Tang

期刊论文

Facile synthesis of polyaniline nanorods to simultaneously enhance the mechanical properties and wear

期刊论文

Automated synthesis of steady-state continuous processes using reinforcement learning

期刊论文

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

期刊论文

Study on a green synthesis of

Aixin WANG, Yuanbin SHE, Jing FAN

期刊论文

Advantageous mechanochemical synthesis of copper(I) selenide semiconductor, characterization, and properties

期刊论文

Biomass to dimethyl ether by gasification/synthesis technology

Tiejun WANG, Yuping LI, Longlong MA, Chuangzhi WU

期刊论文

Multi-resolution texture synthesis from turntable image sequences

Xuedong WANG, Xiaojun WU, Xiaorong ZHANG

期刊论文

Kinematical synthesis of an inversion of the double linked fourbar for morphing wing applications

J. AGUIRREBEITIA, R. AVILéS, I. FERNáNDEZ, M. ABASOLO

期刊论文

Catalytic activity of manganese oxide supported on alumina in the synthesis of quinoxalines

Rekha M., H. Kathyayini, N. Nagaraju

期刊论文

dehydrogenation reaction on high-performance PdAu alloy nanoparticles prepared by the eco-friendly slow synthesis

期刊论文