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Comprehensive kinetostatic modeling and morphology characterization of cable-driven continuum robots

《机械工程前沿（英文）》 2023年 第18卷 第3期 doi: 10.1007/s11465-023-0756-0

摘要： In-situ maintenance is of great significance for improving the efficiency and ensuring the safety of aero-engines. The cable-driven continuum robot (CDCR) with twin-pivot compliant mechanisms, which is enabled with flexible deformation capability and confined space accessibility, has emerged as a novel tool that aims to promote the development of intelligence and efficiency for in-situ aero-engine maintenance. The high-fidelity model that describes the kinematic and morphology of CDCR lays the foundation for the accurate operation and control for in-situ maintenance. However, this model was not well addressed in previous literature. In this study, a general kinetostatic modeling and morphology characterization methodology that comprehensively contains the effects of cable-hole friction, gravity, and payloads is proposed for the CDCR with twin-pivot compliant mechanisms. First, a novel cable-hole friction model with the variable friction coefficient and adaptive friction direction criterion is proposed through structure optimization and kinematic parameter analysis. Second, the cable-hole friction, all-component gravities, deflection-induced center-of-gravity shift of compliant joints, and payloads are all considered to deduce a comprehensive kinetostatic model enabled with the capacity of accurate morphology characterization for CDCR. Finally, a compact continuum robot system is integrated to experimentally validate the proposed kinetostatic model and the concept of in-situ aero-engine maintenance. Results indicate that the proposed model precisely predicts the morphology of CDCR and outperforms conventional models. The compact continuum robot system could be considered a novel solution to perform in-situ maintenance tasks of aero-engines in an invasive manner.

关键词： kinetostatic modeling     morphology characterization     variable friction     continuum robots     in-situ maintenance    

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Review of characterization and modeling of polymer electrolyte fuel cell catalyst layer: The blessing

Jun HUANG, Zhe LI, Jianbo ZHANG

《能源前沿（英文）》 2017年 第11卷 第3期   页码 334-364 doi: 10.1007/s11708-017-0490-6

摘要： Ionomer impregnation represents a milestone in the evolution of polymer electrolyte fuel cell (PEFC) catalyst layers. Ionomer acts as the binder, facilitates proton transport, and thereby drastically improves catalyst utilization and effectiveness. However, advanced morphological and functional characterizations have revealed that up to 60% of Pt nanoparticles can be trapped in the micropores of carbon support particles. Ionomer clusters and oxygen molecules can hardly enter into micropores, leading to low Pt utilization and effectiveness. Moreover, the ionomer thin-films covering Pt nanoparticles can cause significant mass transport loss especially at high current densities. Ionomer-free ultra-thin catalyst layers (UTCLs) emerge as a promising alternative to reduce Pt loading by improving catalyst utilization and effectiveness, while theoretical issues such as the proton conduction mechanism remain puzzling and practical issues such as the rather narrow operation window remain unsettled. At present, the development of PEFC catalyst layer has come to a crossroads: staying ionomer-impregnated or going ionomer-free. It is always beneficial to look back into the past when coming to a crossroads. This paper addresses the characterization and modeling of both the conventional ionomer-impregnated catalyst layer and the emerging ionomer-free UTCLs, featuring advances in characterizing microscale distributions of Pt particles, ionomer, support particles and unraveling their interactions; advances in fundamental understandings of proton conduction and flooding behaviors in ionomer-free UTCLs; advances in modeling of conventional catalyst layers and especially UTCLs; and discussions on high-impact research topics in characterizing and modeling of catalyst layers.

关键词： polymer electrolyte fuel cell     ultra-thin catalyst layer     electrostatic interactions     characterization and modeling     structure-property-performance relation     water management    

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Characterization of phosphorus species and modeling for its organic forms in eutrophic shallow lake sediments

Hongguang CHENG,Xiao PU,Yiting CHEN,Fanghua HAO,Liming DONG

《环境科学与工程前沿（英文）》 2014年 第8卷 第6期   页码 905-921 doi: 10.1007/s11783-014-0650-4

摘要： Variations of phosphorus (P) and its species in surface sediment of Baiyangdian Lake, a eutrophic shallow lake located in North China, were investigated through combination of field survey and numerical calculation based on cluster analysis. P fractionation was performed by a sequential extraction scheme, categorized as loosely bound P (NH Cl-P), reductant soluble P (BD-P), metallic oxide bound P (NaOH-P), calcium bound P (HCl-P) and organic P (Org-P). P concentrations exhibited regional similarities and a total of four sub-areas were identified in which the same rank was HCl-P>Org-P>BD-P ≈ NaOH-P>NH Cl-P. NH Cl-P, BD-P and Org-P were found to contribute to P enrichment in overlying water column. Specifically, labile Org-P acted as a potential pool with a greater contribution in aerobic layer compared to anaerobic layer. A hysteresis (lag= 4 months) existed when labile Org-P concentration was negatively correlated with aerobic layer thickness. In view of magnitude of identified P contributors in sub-areas, higher potential of P release was present in Fuhe River and Tang River estuary areas. On the basis of calibration and verification, the mathematical model with parameter settings applied in this study was improved to serve as a tool for limnology management and eutrophic control.

关键词： phosphorus fractionation     variation characteristics     modeling     sediment     Baiyangdian Lake    

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Modeling of the separation performance of nanofiltration membranes and its role in the applications of

SHANG Weijuan, WANG Daxin, WANG Xiaolin

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 208-215 doi: 10.1007/s11705-007-0038-0

摘要： Although there is a voluminous literature on the determination of structural parameters (the pore radius, the ratio of membrane porosity to membrane thickness) of a nanofiltration (NF) membrane and its separation performance (such as the rejection and the permeation flux) by the simplified Teorell-Meyer-Sievers (TMS) model, little of this research comments on other theories and the consequences of linking modeling evaluation to technological application. Theories used to predict the separation performance of an NF membrane usually include: the non-equilibrium thermodynamic model, the pore model, the space charge model, the TMS model, the electrostatic and steric-hindrance model, and the semiempirical model. In the article, we briefly trace the origins or the general ideas of the above-mentioned theories. From there, recent researches on the characterization of membrane structural parameters and electrical properties (such as the surface charge density ) are reviewed. We then turn to research on the separation performance of an NF membrane for single-component solutions of inorganic electrolytes, neutral organic solutions, and a mixture solution of electrolytes or that of an electrolyte and neutral organic solute. Afterwards, we outline the applications of NF technology in the processes of product separation and conclude with a discussion on the role of models in such applications.

关键词： above-mentioned     TMS     characterization     electrostatic     semiempirical    

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Mechanism and characterization of microplastic aging process: A review

《环境科学与工程前沿（英文）》 2023年 第17卷 第8期 doi: 10.1007/s11783-023-1700-6

摘要：

● Methods for estimating the aging of environmental micro-plastics were highlighted.

关键词： Microplastics     Aging     Degradation     Characterization     Mechanism    

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An experimental characterization of human torso motion

Daniele CAFOLLA,I-Ming CHEN,Marco CECCARELLI

《机械工程前沿（英文）》 2015年 第10卷 第4期   页码 311-325 doi: 10.1007/s11465-015-0352-z

摘要：

The torso plays an important role in the human-like operation of humanoids. In this paper, a method is proposed to analyze the behavior of the human torso by using inertial and magnetic sensing tools. Experiments are conducted to characterize the motion performance of the human torso during daily routine operations. Furthermore, the forces acting on the human body during these operations are evaluated to design and validate the performance of a humanoid robot.

关键词： experimental biomechanics     human torso     analysis     inertial sensor     characterization    

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Synthesis and characterization of norfloxacin biomonomer

Shengxiong DONG, Qiaoping CHEN, Hongfang XIE, Jianhua HUANG

《化学科学与工程前沿（英文）》 2011年 第5卷 第1期   页码 55-59 doi: 10.1007/s11705-010-0537-2

摘要： A novel drug agent named norfloxacin biomonomer was developed in order to solve the problem of low drug content, uneven drug distribution, low molecular weight, and wide molecular weight distribution of polymer drug, based on polyurethane, which was used as an antibacterial agent to control the bacterial infection associated with biofilm formation on polymeric materials used in biologic environments. In this research, norfloxacin biomonomer was synthesized by esterifying the compound of norfloxacin. High-performance liquid chromatography system was used to analyze the purity of the final product and intermediate products, and Fourier transform infrared spectrometer and mass spectrum were used to verify the final product and intermediate products. The results showed that the objective product was developed successfully. The final product of norfloxacin biomonomer could be incorporated into the polyurethane as chain extender.

关键词： norfloxacin     biomonomer     synthesis     characterization    

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Microplastic and Nanoplastic Pollution: Characterization, Transport, Fate, and Remediation Strategies

《环境科学与工程前沿（英文）》 2022年 第16卷 第1期   页码 12-12 doi: 10.1007/s11783-021-1446-y

摘要： Plastics continues to have a critical and essential role in human society such as food packing, product packages and building materials. In the meantime, it has been recognized as a global sustainability priority to study and mitigate pollution of plastics and the associated unknown impacts from ultrafine plastic particles. Microplastic (<5 mm) particles, for instance, have been detected in the aquatic environment globally and have raised scientific interests and environmental concerns. Microplastics (MPs) can enter rivers through a variety of pathways (e.g., wastewater effluent, breakdown of plastic debris) and can negatively impact aquatic organisms through both direct injection with food and indirect contamination from absorbed toxins. MPs can absorb heavy metals, pathogens, and organic contaminants, mainly persistent organic pollutants (POPs) that can be ingested by organisms and introduced into the food web. Meanwhile, MPs may also release potentially toxic substances (e.g., plasticizers, flame retardants and antimicrobial agents) during weathering and degradation. An increasing number of papers are being published during the last years related to the effects of MPs as well as with synergistic effects when associated with MPs and their byproducts such as nanometer sized plastics or nanoplastics. This special issue successfully garnered a collection of research articles that addressed various topics of microplastic or nanoplastic pollution, characteristic, and environmental fate in the water environment. Particularly, this issue reported the seasonable occurrence and distribution of microplastics in different regions (e.g., China and India) from high-latitude nature reserve to sediments and coastal marine environments. Moreover, new sampling and analytical methodologies (e.g., fluorescent labeling) to identify MPs in diver matrixes (e.g., wastewater, sediment, and biota) are critically reviewed. The information is critical for scientists, business leaders, legislators, and the public are to explore and develop solutions that lessen society’s plastic footprint. We thank all authors, reviewers, and editorial staff of FESE for their efforts and contributions to this special issue. Guest Editors: Wen Zhang Department of Civil and Environmental Engineering, New Jersey Institute of Technology (wen.zhang@njit.edu) Melissa Pasquinelli College of Natural Resources, North Carolina State University (melissa_pasquinelli@ncsu.edu) Yang Li School of the Environment Beijing Normal University (liyang_bnu@bnu.edu.cn)
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Preparation and characterization of ZnO/ZnS hybrid photocatalysts via microwave-hydrothermal method

ZHAO Jinglian, WANG Xinping, ZHAO Liang

《环境科学与工程前沿（英文）》 2008年 第2卷 第4期   页码 415-420 doi: 10.1007/s11783-008-0056-2

摘要： The photocatalytic performance of ZnO/ZnS hybrid nanocomposite was largely higher than that of the mere ZnO or ZnS nanoparticles, but the complicated procedure and misdistribution of final products limited its large-scale productions. The exploration of a novel synthesis route of ZnO/ZnS hybrid photocatalysts with high catalytic performance is becoming a crucial step for the large-scale application of ZnO/ZnS hybrid photocatalytic technique. Preparation and characterization of nanosized ZnO/ZnS hybrid photocatalysts were studied in this paper. The photocatalysts were obtained via microwave-hydrothermal crystallization with the help of sodium citrate. The products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), particle size distribution (PSD), and Fourier transformed infrared spectroscopy (FT-IR). The results indicated that so-synthesized ZnO/ZnS samples consisted of the high pure cubic (sphalerite) ZnS and hexagonal ZnO nanocrystallines with a narrow particle size distribution. The possible formation mechanisms of ZnO/ZnS nanocrystallines were mainly attributed to the superficially protective effect of citrate. The photocatalytic experiments demonstrated that the ZnO/ZnS photocatalysts exhibited a higher catalytic activity for the degradation of acid fuchsine than other monocomponents.

关键词： large-scale     hexagonal     misdistribution     characterization     nanocomposite    

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Mechanical properties characterization of different types of masonry infill walls

André FURTADO, Hugo RODRIGUES, António ARÊDE, Humberto VARUM

《结构与土木工程前沿（英文）》 2020年 第14卷 第2期   页码 411-434 doi: 10.1007/s11709-019-0602-y

摘要： It is remarkable, the recent advances concerning the development of numerical modeling frameworks to simulate the infill panels’ seismic behavior. However, there is a lack of experimental data of their mechanical properties, which are of full importance to calibrate the numerical models. The primary objective of this paper is to present an extensive experimental campaign of mechanical characterization tests of infill masonry walls made with three different types of masonry units: lightweight vertical hollow concrete blocks and hollow clay bricks. Four different types of experimental tests were carried out, namely: compression strength tests, diagonal tensile strength tests, and flexural strength tests parallel and perpendicular to the horizontal bed joints. A total amount of 80 tests were carried out and are reported in the present paper. The second objective of this study was to compare the mechanical properties of as-built and existing infill walls. The results presented and discussed herein, will be in terms of strain-stress curves and damages observed within the tests. It was observed a fragile behavior in the panels made with hollow clay horizontal bricks, without propagation of cracks. The plaster increased the flexural strength by 57%.

关键词： masonry infill walls     experimental characterization     compression strength     shear diagonal strength     flexural strength    

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Retraction note to: Synthesis, characterization and assessment thermal properties of clay based nanopigments

Mohammad Banimahd Kievani,Milad Edraki

《化学科学与工程前沿（英文）》 2016年 第10卷 第3期   页码 440-440 doi: 10.1007/s11705-016-1573-3

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Recent advances in gold-metal oxide core-shell nanoparticles: Synthesis, characterization, and their

Michelle Lukosi,Huiyuan Zhu,Sheng Dai

《化学科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 39-56 doi: 10.1007/s11705-015-1551-1

摘要： Heterogeneous catalysis with core-shell structures has been a large area of focus for many years. This paper reviews the most recent work and research in core-shell catalysts utilizing noble metals, specifically gold, as the core within a metal oxide shell. The advantage of the core-shell structure lies in its capacity to retain catalytic activity under thermal and mechanical stress, which is a pivotal consideration when synthesizing any catalyst. This framework is particularly useful for gold nanoparticles in protecting them from sintering so that they retain their size, structure, and most importantly their catalytic efficiency. The different methods of synthesizing such a structure have been compiled into three categories: seed-mediated growth, post selective oxidation treatment, and one-pot chemical synthesis. The selective oxidation of carbon monoxide and reduction of nitrogen containing compounds, such as nitrophenol and nitrostyrene, have been studied over the past few years to evaluate the functionality and stability of the core-shell catalysts. Different factors that could influence the catalyst’s performance are the size, structure, choice of metal oxide shell and noble metal core and thereby the interfacial synergy and lattice mismatch between the core and shell. In addition, the morphology of the shell also plays a critical role, including its porosity, density, and thickness. This review covers the synthesis and characterization of gold-metal oxide core-shell structures, as well as how they are utilized as catalysts for carbon monoxide (CO) oxidation and selective reduction of nitrogen-containing compounds.

关键词： core-shell     characterization     core-shell structure     Different     stability    

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Challenges in characterization of nanoplastics in the environment

Wen Zhang1 , Qi Wang2 , Hao Chen2

《环境科学与工程前沿（英文）》 2022年 第16卷 第1期   页码 11-11 doi: 10.1007/s11783-021-1445-z

摘要： Plastic pollution has been a legacy environment problems and more recently, the plastic particles, especially those ultrafine or small plastics particles, are widely recognized with increasing environmental and ecological impacts. Among small plastics, microplastics are intensively studied, whereas the physicochemical properties, environmental abundance, chemical states, bioavailability and toxicity toward organisms of nanoplastics are inadequately investigated. There are substantial difficulties in separation, visualization and chemical identification of nanoplastics due to their small sizes, relatively low concentrations and interferences from co-existing substances (e.g., dyes or natural organic matters). Moreover, detection of polymers at nanoscale is largely hampered by the detection limit or sensitivity for existing spectral techniques such as Transformed Infrared Spectroscopy (FTIR) or Raman Spectroscopy. This article critically examined the current state of art techniques that are exclusively reported for nanoplastic characterization in environmental samples. Based on their operation principles, potential applications and limitations of these analytical techniques are carefully analyzed.
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Review on design, preparation and performance characterization of gelled fuels for advanced propulsion

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 819-837 doi: 10.1007/s11705-021-2122-2

摘要： With the increasing demand for high-performance and safe fuels in aerospace propulsion systems, gelled fuels have attracted increasing attention. Because of their unique structure, gelled fuels exhibit the advantages of both solid and liquid fuels, such as high energy density, controllable thrust and storage safety. This review provides an overview on design, preparation and performance characterization of gelled fuels. The composition, preparation process and gelation mechanism of gelled high-energy-density fuels are described. Considering these aspects, the rheology and flow behavior of gelled fuels is summarized in terms of the shear thinning property, dynamic viscoelasticity and thixotropy. Moreover, the progress of atomization of gelled fuels is reviewed with a focus on the effect of atomizing nozzles. In addition, the experiments and theoretical models of single droplet combustion and combustor combustion are described. Finally, research directions for the development and application of gelled fuels are suggested.

关键词： gelled fuels     high-energy-density fuels     rheological properties     atomization     combustion    

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Synthesis, characterization and assessment thermal properties of clay based nanopigments

Mohammad Banimahd KIEVANI, Milad EDRAKI

《化学科学与工程前沿（英文）》 2015年 第9卷 第1期   页码 40-45 doi: 10.1007/s11705-015-1505-7

摘要： Nano-clay based pigments (NCP) are new type of pigments composed of organic dyes and layered silicate-clay nano-particles, and have already been used in polymeric coatings to improve mechanical thermal and stability properties. In this paper, the basic blue 41(BB41) was intercalated into Na - montmorillonite in an aqueous medium. The dye-intercalated montmorillonite was centrifuged, dried, and milled to prepare the nanopigment particles. X-ray diffraction showed an increase in the basal spacing, thus confirming intercalation of the BB41 molecules within the nanostructures of the interlayer spaces. Fourier transform infrared spectroscopy was used for identifying the functional groups and chemical bounding of Na -montmorillonite, BB41 and montmorillonite-BB41. The morphology of NCP was also studied by transmission electron microscopy. Finally, thermo-gravimetric analysis and differential thermograms suggested the thermal stability of the intercalated dye was improved.

关键词： nanopigment     layered silicate     cationic dye     thermal properties    

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标题 作者 时间 类型 操作

Comprehensive kinetostatic modeling and morphology characterization of cable-driven continuum robots

期刊论文

Review of characterization and modeling of polymer electrolyte fuel cell catalyst layer: The blessing

Jun HUANG, Zhe LI, Jianbo ZHANG

期刊论文

Characterization of phosphorus species and modeling for its organic forms in eutrophic shallow lake sediments

Hongguang CHENG,Xiao PU,Yiting CHEN,Fanghua HAO,Liming DONG

期刊论文

Modeling of the separation performance of nanofiltration membranes and its role in the applications of

SHANG Weijuan, WANG Daxin, WANG Xiaolin

期刊论文

Mechanism and characterization of microplastic aging process: A review

期刊论文

An experimental characterization of human torso motion

Daniele CAFOLLA,I-Ming CHEN,Marco CECCARELLI

期刊论文

Synthesis and characterization of norfloxacin biomonomer

Shengxiong DONG, Qiaoping CHEN, Hongfang XIE, Jianhua HUANG

期刊论文

Microplastic and Nanoplastic Pollution: Characterization, Transport, Fate, and Remediation Strategies

期刊论文

Preparation and characterization of ZnO/ZnS hybrid photocatalysts via microwave-hydrothermal method

ZHAO Jinglian, WANG Xinping, ZHAO Liang

期刊论文

Mechanical properties characterization of different types of masonry infill walls

André FURTADO, Hugo RODRIGUES, António ARÊDE, Humberto VARUM

期刊论文

Retraction note to: Synthesis, characterization and assessment thermal properties of clay based nanopigments

Mohammad Banimahd Kievani,Milad Edraki

期刊论文

Recent advances in gold-metal oxide core-shell nanoparticles: Synthesis, characterization, and their

Michelle Lukosi,Huiyuan Zhu,Sheng Dai

期刊论文

Challenges in characterization of nanoplastics in the environment

Wen Zhang1 , Qi Wang2 , Hao Chen2

期刊论文

Review on design, preparation and performance characterization of gelled fuels for advanced propulsion

期刊论文

Synthesis, characterization and assessment thermal properties of clay based nanopigments

Mohammad Banimahd KIEVANI, Milad EDRAKI

期刊论文