资源类型

期刊论文 127

会议视频 3

年份

2023 13

2022 15

2021 8

2020 10

2019 6

2018 9

2017 10

2016 3

2015 3

2014 6

2013 1

2012 5

2011 3

2010 5

2009 7

2008 9

2007 9

2006 2

2004 2

2000 1

展开 ︾

关键词

原子力显微镜 4

化学吸收 2

原子层沉积 2

原子结构 2

大气污染 2

360°表征 1

N-糖组 1

N-糖基化 1

COVID-19 1

Cu(In 1

Dirac理论 1

Ga)Se2光伏组件 1

IgG抗体 1

MnAl 1

N 1

N-二乙基乙醇胺 1

N-聚糖 1

VO2薄膜 1

hACE2 1

展开 ︾

检索范围:

排序: 展示方式:

Preconcentration of trace elements by adsorption onto a niobium wire for electrothermal atomization atomicabsorption spectrometry with a tungsten tube atomizer

Satoshi KANECO, Hiroaki KITANAGA, Hideyuki KATSUMATA, Tohru SUZUKI

《化学科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 432-435 doi: 10.1007/s11705-012-1219-z

摘要: In the present work, a new preconcentration method of trace elements by adsorption onto a niobium wire has been developed for electrothermal atomization atomic absorption spectrometry (ETAAS) with a tungsten tube atomizer. Detection limits (pg·mL ) by this method combined with ETAAS were 45 for bismuth, 7.0 for cadmium, 20 for copper, 1.3 for gold, 36 for lead, 65 for manganese, 9.5 for rhodium and 19 for silver.

关键词: preconcentration     adsorption onto niobium wire     electrothermal atomization atomic absorption spectrometry     tungsten tube atomizer     trace elements    

Ultrasound-assisted emulsification solidified floating organic drop microextraction for the determination of trace amounts of copper in water samples

Qingyun CHANG, Jingwen ZHANG, Xin DU, Jingjun MA, Jingci LI,

《环境科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 187-195 doi: 10.1007/s11783-010-0030-7

摘要: A simple and efficient liquid-phase microextraction (LPME) technique was developed using ultrasound-assisted emulsification solidified floating organic drop microextraction (USAE-SFODME) combined with flame atomic absorption spectrometry, for the extraction and determination of trace copper in water samples. 1-(2-Pyridylazo)-2-naphthol (PAN) was used as chelating agent. Microextraction efficiency factors (including extraction solvent type, extraction volume, time, temperature, and pH), the amount of the chelating agent, and salt effect were investigated and optimized. Under the optimum extraction conditions, figures of merit of the proposed method were evaluated. The calibration graph was linear in the range of 20–600 g·L with a detection limit of 0.76 g·L. The relative standard deviation (R.S.D) for ten replicate measurements of 20 and 400 g·L of copper was 3.83% and 2.65%, respectively. Finally, the proposed method was applied to tap water, river water, and sea water, and accuracy was assessed through the analysis of certified reference water or recovery experiments.

关键词: ultrasound-assisted emulsification     solidified floating organic drop microextraction     flame atomic absorption spectrometry     preconcentration     copper    

A magnetic adsorbent based on salicylic acid-immobilized magnetite nano-particles for pre-concentration of Cd(II) ions

Hossein Abdolmohammad-Zadeh, Arezu Salimi

《化学科学与工程前沿(英文)》 2021年 第15卷 第2期   页码 450-459 doi: 10.1007/s11705-020-1930-0

摘要: In this research, an eco-friendly magnetic adsorbent based on Fe O /salicylic acid nanocomposite was fabricated using a facile one-pot co-precipitation method. The crystalline and morphological characterization of the prepared nanocomposite was performed by field emission scanning electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The nanocomposite was employed as a magnetic solid-phase extraction agent for separation of Cd(II) ions from synthetic solutions. Some experimental factors affecting the extraction efficiency were investigated and optimized. Following elution with acetic acid (pH 3.5), the pre-concentrated analyte was quantified by flame atomic absorption spectrometry. In optimal conditions, a linear calibration graph was achieved in the concentration range of 0.2‒30 ng·mL with a determination coefficient ( ) of 0.9953. The detection limit, the enhancement factor, inter- and intra-day relative standard deviations (for six consecutive extractions at the concentration level of 10 ng·mL ) were 0.04 ng·mL , 100, 2.38% and 1.52%, respectively. To evaluate the accuracy of the method, a certified reference material (NIST SRM 1643e) was analyzed, and there was a good agreement between the certified and the measured values. It was successfully utilized to determine cadmium in industrial wastewater samples and the attained relative recovery values were between 96.8% and 103.2%.

关键词: cadmium     magnetic solid-phase extraction     Fe3O4 nanoparticles     Fe3O4/salicylic acid nanocomposite     flame atomic absorption spectrometry    

Applications of atomic force microscopy in immunology

Jiping Li, Yuying Liu, Yidong Yuan, Bo Huang

《医学前沿(英文)》 2021年 第15卷 第1期   页码 43-52 doi: 10.1007/s11684-020-0769-6

摘要: Cellular mechanics, a major regulating factor of cellular architecture and biological functions, responds to intrinsic stresses and extrinsic forces exerted by other cells and the extracellular matrix in the microenvironment. Cellular mechanics also acts as a fundamental mediator in complicated immune responses, such as cell migration, immune cell activation, and pathogen clearance. The principle of atomic force microscopy (AFM) and its three running modes are introduced for the mechanical characterization of living cells. The peak force tapping mode provides the most delicate and desirable virtues to collect high-resolution images of morphology and force curves. For a concrete description of AFM capabilities, three AFM applications are discussed. These applications include the dynamic progress of a neutrophil-extracellular-trap release by neutrophils, the immunological functions of macrophages, and the membrane pore formation mediated by perforin, streptolysin O, gasdermin D, or membrane attack complex.

关键词: cellular mechanics     atomic force microscopy     neutrophil extracellular trap     macrophage phagocytosis     pore formation    

Bicontinuous porous membranes with micro-nano composite structure using a facile atomization-assisted

《化学科学与工程前沿(英文)》 2022年 第16卷 第8期   页码 1268-1280 doi: 10.1007/s11705-022-2143-5

摘要: The micro-nano composite structure can endow separation membranes with special surface properties, but it often has the problems of inefficient preparation process and poor structural stability. In this work, a novel atomization-assisted nonsolvent induced phase separation method, which is also highly efficient and very simple, has been developed. By using this method, a bicontinuous porous microfiltration membrane with robust micro-nano composite structure was obtained via commercially available polymers of polyacrylonitrile and polyvinylpyrrolidone. The formation mechanism of the micro-nano composite structure was proposed. The microphase separation of polyacrylonitrile and polyvinylpyrrolidone components during the atomization pretreatment process and the hydrogen bonding between polyacrylonitrile and polyvinylpyrrolidone molecules should have resulted in the nano-protrusions on the membrane skeleton. The membrane exhibits superhydrophilicity in air and superoleophobicity underwater. The membrane can separate both surfactant-free and surfactant-stabilized oil-in-water emulsions with high separation efficiency and permeation flux. With excellent antifouling property and robust microstructure, the membrane can easily be recycled for long-term separation. Furthermore, the scale-up verification from laboratory preparation to continuous production has been achieved. The simple, efficient, cost-effective preparation method and excellent membrane properties indicate the great potential of the developed membranes in practical applications.

关键词: atomization     nonsolvent induced phase separation     bicontinuous porous structure     micro-nano composite structure     oil-water separation    

Atomic and close-to-atomic scale manufacturing—A trend in manufacturing development

Fengzhou FANG

《机械工程前沿(英文)》 2016年 第11卷 第4期   页码 325-327 doi: 10.1007/s11465-016-0402-1

摘要:

Manufacturing is the foundation of a nation’s economy. It is the primary industry to promote economic and social development. To accelerate and upgrade China’s manufacturing sector from “precision manufacturing” to “high-performance and high-quality manufacturing”, a new breakthrough should be found in terms of achieving a “leap-frog development”. Unlike conventional manufacturing, the fundamental theory of “Manufacturing 3.0” is beyond the scope of conventional theory; rather, it is based on new principles and theories at the atomic and/or close-to-atomic scale. Obtaining a dominant role at the international level is a strategic move for China’s progress.

关键词: atomic manufacturing     Manufacturing 3.0     Manufacturing 2025     Industry 4.0    

Design and analysis of electrothermal metasurfaces

Xiu LIU, Zhuo LI, Zexiao WANG, Hyeong Seok YUN, Sheng SHEN

《能源前沿(英文)》 2023年 第17卷 第1期   页码 134-140 doi: 10.1007/s11708-022-0841-9

摘要: Electrothermal metasurfaces have garnered considerable attention owing to their ability to dynamically control thermal infrared radiation. Although previous studies were mainly focused on metasurfaces with infinite unit cells, in practice, the finite-size effect can be a critical design factor for developing thermal metasurfaces with fast response and broad temperature uniformity. Here, we study the thermal metasurfaces consisting of gold nanorods with a finite array size, which can achieve a resonance close to that of the infinite case with only several periods. More importantly, such a small footprint due to the finite array size yields response time down to a nanosecond level. Furthermore, the number of the unit cells in the direction perpendicular to the axis of nanorods is found to be insensitive to the resonance and response time; thus, providing a tunable aspect ratio that can boost the temperature uniformity in the sub-Kelvin level.

关键词: modulated thermal infrared radiation     metasurface     nanosecond response time     sub-Kelvin temperature uniformity     finite size     aspect ratio    

aromatic hydrocarbons predicting from general connectivity based hierarchy with discrete correction of atomization

《化学科学与工程前沿(英文)》 2022年 第16卷 第12期   页码 1743-1750 doi: 10.1007/s11705-022-2184-9

摘要: The standard enthalpy of formation is an important predictor of the reaction heat of a chemical reaction. In this work, a high-precision method was developed to calculate accurate standard enthalpies of formation for polycyclic aromatic hydrocarbons based on the general connectivity based hierarchy (CBH) with the discrete correction of atomization energy. Through a comparison with available experimental findings and other high-precision computational results, it was found that the present method can give a good description of enthalpy of formation for polycyclic aromatic hydrocarbons. Since CBH schemes can broaden the scope of application, this method can be used to investigate the energetic properties of larger polycyclic aromatic hydrocarbons to achieve a high-precision calculation at the CCSD(T)/CBS level. In addition, the energetic properties of CBH fragments can be accurately calculated and integrated into a database for future use, which will increase computational efficiency. We hope this work can give new insights into the energetic properties of larger systems.

关键词: standard enthalpy of formation     polycyclic aromatic hydrocarbons     connectivity based hierarchy     high-precision calculation    

Crystallographic orientation effect on cutting-based single atomic layer removal

Wenkun XIE, Fengzhou FANG

《机械工程前沿(英文)》 2020年 第15卷 第4期   页码 631-644 doi: 10.1007/s11465-020-0599-x

摘要: The ever-increasing requirements for the scalable manufacturing of atomic-scale devices emphasize the significance of developing atomic-scale manufacturing technology. The mechanism of a single atomic layer removal in cutting is the key basic theoretical foundation for atomic-scale mechanical cutting. Material anisotropy is among the key decisive factors that could not be neglected in cutting at such a scale. In the present study, the crystallographic orientation effect on the cutting-based single atomic layer removal of monocrystalline copper is investigated by molecular dynamics simulation. When undeformed chip thickness is in the atomic scale, two kinds of single atomic layer removal mechanisms exist in cutting-based single atomic layer removal, namely, dislocation motion and extrusion, due to the differing atomic structures on different crystallographic planes. On close-packed crystallographic plane, the material removal is dominated by the shear stress-driven dislocation motion, whereas on non-close packed crystallographic planes, extrusion-dominated material removal dominates. To obtain an atomic, defect-free processed surface, the cutting needs to be conducted on the close-packed crystallographic planes of monocrystalline copper.

关键词: ACSM     single atomic layer removal mechanism     crystallographic orientation effect     mechanical cutting     Manufacturing III    

Shape and topology optimization for tailoring the ratio between two flexural eigenfrequencies of atomic

Qi XIA,Tao ZHOU,Michael Yu WANG,Tielin SHI

《机械工程前沿(英文)》 2014年 第9卷 第1期   页码 50-57 doi: 10.1007/s11465-014-0286-x

摘要:

In an operation mode of atomic force microscopy that uses a higher eigenmode to determine the physical properties of material surface, the ratio between the eigenfrequency of a higher flexural eigenmode and that of the first flexural eigenmode was identified as an important parameter that affects the sensitivity and accessibility. Structure features such as cut-out are often used to tune the ratio of eigenfrequencies and to enhance the performance. However, there lacks a systematic and automatic method for tailoring the ratio. In order to deal with this issue, a shape and topology optimization problem is formulated, where the ratio between two eigenfrequencies is defined as a constraint and the area of the cantilever is maximized. The optimization problem is solved via the level set based method.

关键词: atomic force microscopy     cantilever probe     eigenfrequency     optimization    

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    

Nanostructured gold films exhibiting almost complete absorption of light at visible wavelengths

Hanbin Zheng, Christine Picard, Serge Ravaine

《化学科学与工程前沿(英文)》 2018年 第12卷 第2期   页码 247-251 doi: 10.1007/s11705-018-1710-2

摘要: Nanostructured metal surfaces have been known to exhibit properties that deviate from that of the bulk material. By simply modifying the texture of a metal surface, various unique optical properties can be observed. In this paper, we present a simple two step electrochemical process combining electrodeposition and anodization to generate black gold surfaces. This process is simple, versatile and up-scalable for the production of large surfaces. The black gold films have remarkable optical behavior as they absorb more than 93% of incident light over the entire visible spectrum and also exhibit no specular reflectance. A careful analysis by scanning electron microscopy reveals that these unique optical properties are due to their randomly rough surface, as they consist in a forest of dendritic microstructures with a nanoscale roughness. This new type of black films can be fabricated to a large variety of substrates, turning them to super absorbers with potential applications in photovoltaic solar cells or highly sensitive detectors and so on.

关键词: nanostructuration     light absorption     coating     gold     electrodeposition     anodization    

Effect of light scattering on the performance of a direct absorption solar collector

Kwang Hyun WON, Bong Jae LEE

《能源前沿(英文)》 2018年 第12卷 第1期   页码 169-177 doi: 10.1007/s11708-018-0527-5

摘要: Recently, a solar thermal collector often employs nanoparticle suspension to absorb the solar radiation directly by a working fluid as well as to enhance its thermal performance. The collector efficiency of a direct absorption solar collector (DASC) is very sensitive to optical properties of the working fluid, such as absorption and scattering coefficients. Most of the existing studies have neglected particle scattering by assuming that the size of nanoparticle suspension is much smaller than the wavelength of solar radiation (i.e., Rayleigh scattering is applicable). If the nanoparticle suspension is made of metal, however, the scattering cross-section of metallic nanoparticles could be comparable to their absorption cross-section depending on the particle size, especially when the localized surface plasmon (LSP) is excited. Therefore, for the DASC utilizing a plasmonic nanofluid supporting the LSP, light scattering from metallic particle suspension must be taken into account in the thermal analysis. The present study investigates the scattering effect on the thermal performance of the DASC employing plasmonic nanofluid as a working fluid. In the analysis, the Monte Carlo method is employed to numerically solve the radiative transfer equation considering the volume scattering inside the nanofluid. It is found that the light scattering can improve the collector performance if the scattering coefficient of nanofluid is carefully engineered depending on its value of the absorption coefficient.

关键词: direct absorption solar collector     plasmonic nanofluid     light scattering    

Performance analysis of solar absorption-subcooled compression hybrid refrigeration system in subtropical

Xiangyang YE,Liming LIU,Zeyu LI

《能源前沿(英文)》 2019年 第13卷 第1期   页码 185-192 doi: 10.1007/s11708-017-0452-z

摘要: Solar absorption-subcooled compression hybrid refrigeration system is a new type of efficient and economical solar refrigeration device which always meets the demand of cooling load with the change of solar irradiance. The performance of the hybrid system is higher due to the improvement of evaporator temperature of absorption subsystem. But simultaneously, the variation of working process as well as performance is complicated since the absorption and compression subsystems are coupled strongly. Based on the measured meteorological data of Guangzhou, a subtropical city in south China, a corresponding parametric model has been developed for the hybrid refrigeration system, and a program written by Fortran has been used to analyze the performance of the hybrid system under different external conditions. As the condensation temperature ranges from 38°C to 50°C, the working time fraction of the absorption subsystem increases from 75% to 85%. Besides, the energy saving fraction also increases from 5.31% to 6.02%. The average COP of the absorption subsystem is improved from 0.366 to 0.407. However, when the temperature of the absorption increases from 36°C to 48°C, the average COP of hybrid system decreases from 2.703 to 2.312. Moreover, the working time fraction of the absorption subsystem decreases from 80% to 71.7%. The energy saving fraction falls from 5.67% to 5.08%. In addition, when the evaporate temperature increases from 4°C to 14°C, the average COP of the absorption subsystem decreases from 0.384 to 0.365. The work of the compressor decreases from 48.2 kW to 32.8 kW and the corresponding average COP of the absorption subsystem is improved from 2.591 to 3.082.

关键词: solar     absorption-subcooled     compression hybrid     dynamic simulation     performance analysis    

Effect of fine solid particles on absorption rate of gaseous CO

LU Sumin, MA Youguang, SHEN Shuhua, ZHU Chunying

《化学科学与工程前沿(英文)》 2008年 第2卷 第4期   页码 368-372 doi: 10.1007/s11705-008-0067-3

摘要: The influence of the properties of solid particles in slurry on the absorption of CO in the slurry was investigated in a stirred thermostatic reactor. The absorption experiments were carried out in three different slurries consisting of water, cyclohexane and soybean oil, respectively, and three kinds of solid particles (active carbon, active alumina and silica gel) were incorporated into each of the above mentioned slurries separately. The experimental results show that the active carbon particles could enhance the absorption rate of gaseous CO in the aqueous slurry, while in the cyclohexane slurry, active carbon particles indicated no the absorption enhancement effect. However, it was observed that the active alumina and silica gel particles could enhance the absorption rate of CO in the cyclohexane slurry. These phenomena indicate that the solid particles, which could enhance the gaseous CO absorption rate, should possess two properties simultaneously, i.e. they rejected the solvent and had higher adsorption capacity for the solute. The experimental results also show that, as for those solid particles which could enhance the gas absorption rate, the enhancement increased quickly with the increase of solid concentration in slurry at first, and then reached a constant value gradually. It was also found that the enhancement factor was related to the coverage fraction of solid particles on the gas-liquid interface, and due to the reduction of surface fraction with increasing stirred speed, the enhancement factor decreased.

关键词: constant     influence     soybean     solvent     concentration    

标题 作者 时间 类型 操作

Preconcentration of trace elements by adsorption onto a niobium wire for electrothermal atomization atomicabsorption spectrometry with a tungsten tube atomizer

Satoshi KANECO, Hiroaki KITANAGA, Hideyuki KATSUMATA, Tohru SUZUKI

期刊论文

Ultrasound-assisted emulsification solidified floating organic drop microextraction for the determination of trace amounts of copper in water samples

Qingyun CHANG, Jingwen ZHANG, Xin DU, Jingjun MA, Jingci LI,

期刊论文

A magnetic adsorbent based on salicylic acid-immobilized magnetite nano-particles for pre-concentration of Cd(II) ions

Hossein Abdolmohammad-Zadeh, Arezu Salimi

期刊论文

Applications of atomic force microscopy in immunology

Jiping Li, Yuying Liu, Yidong Yuan, Bo Huang

期刊论文

Bicontinuous porous membranes with micro-nano composite structure using a facile atomization-assisted

期刊论文

Atomic and close-to-atomic scale manufacturing—A trend in manufacturing development

Fengzhou FANG

期刊论文

Design and analysis of electrothermal metasurfaces

Xiu LIU, Zhuo LI, Zexiao WANG, Hyeong Seok YUN, Sheng SHEN

期刊论文

aromatic hydrocarbons predicting from general connectivity based hierarchy with discrete correction of atomization

期刊论文

Crystallographic orientation effect on cutting-based single atomic layer removal

Wenkun XIE, Fengzhou FANG

期刊论文

Shape and topology optimization for tailoring the ratio between two flexural eigenfrequencies of atomic

Qi XIA,Tao ZHOU,Michael Yu WANG,Tielin SHI

期刊论文

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

期刊论文

Nanostructured gold films exhibiting almost complete absorption of light at visible wavelengths

Hanbin Zheng, Christine Picard, Serge Ravaine

期刊论文

Effect of light scattering on the performance of a direct absorption solar collector

Kwang Hyun WON, Bong Jae LEE

期刊论文

Performance analysis of solar absorption-subcooled compression hybrid refrigeration system in subtropical

Xiangyang YE,Liming LIU,Zeyu LI

期刊论文

Effect of fine solid particles on absorption rate of gaseous CO

LU Sumin, MA Youguang, SHEN Shuhua, ZHU Chunying

期刊论文