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Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

Carsten-Rene Arlt, Dominik Brekel, Stefan Neumann, David Rafaja, Matthias Franzreb

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1346-1355 doi: 10.1007/s11705-021-2040-3

摘要： The size fractionation of magnetic nanoparticles is a technical problem, which until today can only be solved with great effort. Nevertheless, there is an important demand for nanoparticles with sharp size distributions, for example for medical technology or sensor technology. Using magnetic chromatography, we show a promising method for fractionation of magnetic nanoparticles with respect to their size and/or magnetic properties. This was achieved by passing magnetic nanoparticles through a packed bed of fine steel spheres with which they interact magnetically because single domain ferro-/ferrimagnetic nanoparticles show a spontaneous magnetization. Since the strength of this interaction is related to particle size, the principle is suitable for size fractionation. This concept was transferred into a continuous process in this work using a so-called simulated moving bed chromatography. Applying a suspension of magnetic nanoparticles within a size range from 20 to 120 nm, the process showed a separation sharpness of up to 0.52 with recovery rates of 100%. The continuous feed stream of magnetic nanoparticles could be fractionated with a space-time-yield of up to 5 mg/(L∙min). Due to the easy scalability of continuous chromatography, the process is a promising approach for the efficient fractionation of industrially relevant amounts of magnetic nanoparticles.

关键词： magnetic chromatography     simulated moving bed chromatography     magnetic nanoparticles     size fractionation    

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Variation in humic and fulvic acids during thermal sludge treatment assessed by size fractionation, elementary

Yuning YANG,Huan LI,Jinyi LI

《环境科学与工程前沿（英文）》 2014年 第8卷 第6期   页码 854-862 doi: 10.1007/s11783-014-0755-9

摘要： Thermal pretreatment can be applied to sludge anaerobic digestion or dewatering. To analyze the variation in humic substances during thermal sludge treatment, sludge humic and fulvic acids were extracted before and after 30-min thermal treatment at 180°C, and then their contents, molecular weight distributions, elementary compositions, and spectral characteristics were compared. The results showed that the total contents of humic and fulvic acids in the sludge almost remained constant during thermal treatment, but 35% of humic and fulvic acids were dissolved from the sludge solids. Moreover, both humic and fulvic acids were partly decomposed and 32% of humic acids were converted to fulvic acids. The median value of the molecular weights of humic acids decreased from 81 to 41 kDa and that of fulvic acids decreased from 15 to 2 kDa. Besides the reduction in molecular size, the chemical structures of humic and fulvic acids also exhibited a slight change, i.e. some oxygen functional groups disappeared and aromatic structures increased after thermal sludge treatment.

关键词： sludge     thermal treatment     humic acids     fulvic acids    

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The size distribution of airborne bacteria and human pathogenic bacteria in a commercial composting plant

《环境科学与工程前沿（英文）》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1356-4

摘要：

•Bacterial concentrations from eight stages were 104–105copies/m3.

关键词： Size distribution     Airborne bacteria     Biological diversity     Human pathogenic bacteria     Composting plants    

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Particle size distribution and shape control of Au nanoparticles used for particle gun

S. Kida, M. Ichiji, J. Watanabe, I. Hirasawa

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 60-64 doi: 10.1007/s11705-013-1313-x

摘要： Au nanoparticles are expected for the media to transfer genes into plants. However, the control of particle size distribution (PSD) and shape of Au nanoparticles is too difficult to design and prepare particles with suitable quality for the gene supporting media. Reduction crystallization experiments were performed in aqueous solution in order to clarify the effect of feeding conditions such as feeding profile, feeding rate, and feeding amount on PSD and shape of Au nanoparticles. Ascorbic acid (AsA) was selected as a reducing agent because it is safe for plants. Au particles of 50 nm, 50–200 nm, and 150–400 nm were obtained in batch operation, single-jet, and double-jet, respectively. Moreover, in single-jet and double-jet, the mean size of the obtained Au particles increases with the decrease of feeding rate or the increase of feeding amount. It is concluded that PSD of Au nanoparticles can be controlled in the range of 50–400 nm by changing feeding conditions of AsA and HAuCl aqueous solution.

关键词： reduction crystallization     particle size distribution     gene transferring media    

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A better way to do small-for-size liver transplantation in rats

null

《医学前沿（英文）》 2011年 第5卷 第1期   页码 106-110 doi: 10.1007/s11684-011-0113-2

摘要：

Establishing a model for small-for-size liver transplantation is the basis for this study of partial and living donor graft liver transplantation. This study aims to explore a simpler and more effective way of establishing a 30% small-for-size liver transplantation in rats. Sprague-Dawley rats were selected as the donors and recipients. Small-for-size orthotopic liver transplantation was performed using Kamada’s two-cuff method. The donor’s liver was flushed via the abdominal aorta and hepatectomy was performed in situ. The animals were divided into three groups depending on the graft selected, with 40 pairs of rats in each group. In group I, the median lobe of the liver was used as graft; in group II, the right half of the median lobe and the right lobe were used as graft; and in group III, the median and right lobes were used as graft. In groups I and II, the bodyweights of donors were the same as those of recipients; however, in group III the bodyweights of donors were 100–120 g less than those of the recipients. The duration needed for transplantation, the 7-day survival rates, and the technical complication rates were compared among these three groups. The time required for hepatectomy was shorter in group III compared with groups I and II (8.8?±?0.7 min vs. 11.5?±?1.1 min and 10.1?±?1.0 min, P = 0.001). The cold ischemia time for the grafts, the anhepatic times, and the transplantation times for the recipients were not significantly different among the three groups. Compared with groups I and II, the incidence of bleeding, bile leakage, and inferior vena caval strictures were significantly decreased in group III (P<0.05). No significant differences between the three groups were found based on other complications after the operation (P>0.05). Group III had better 7-day survival rates and longer median survival times but the differences were not statistically significant. The method of small for donor bodyweight using the median and right lobes for grafting may be a more effective and simpler way of establishing a 30% small-for-size liver transplantation in rats, as shown by the shorter hepatectomy time and the occurrence of fewer complications after the operation.

关键词： liver transplantation     small-for-size     rats    

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Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

《环境科学与工程前沿（英文）》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1557-0

摘要：

● A series of Cu-ZSM-5 catalysts were tested for DMF selective catalytic oxidation.

关键词： N     N-Dimethylformamide     Selective catalytic oxidation     Cu-ZSM-5     CuO particle size    

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Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

《结构与土木工程前沿（英文）》   页码 1163-1187 doi: 10.1007/s11709-023-0987-5

摘要： In this study, the concrete cone capacity, concrete cone angle, and load–displacement response of cast-in headed anchors in geopolymer concrete are explored using numerical analyses. The concrete damaged plasticity (CDP) model in ABAQUS is used to simulate the behavior of concrete substrates. The tensile behavior of anchors in geopolymer concrete is compared with that in normal concrete as well as that predicted by the linear fracture mechanics (LFM) and concrete capacity design (CCD) models. The results show that the capacity of the anchors in geopolymer concrete is 30%–40% lower than that in normal concrete. The results also indicate that the CCD model overestimates the capacity of the anchors in geopolymer concrete, whereas the LFM model provides a much more conservative prediction. The extent of the difference between the predictions by the numerical analysis and those of the above prediction models depends on the effective embedment depth of the anchor and the anchor head size. The influence of concrete surface cracking on the capacity of the anchor is shown to depend on the location of the crack and the effective embedment depth. The influence of the anchor head profile on the tensile capacity of the anchors is found to be insignificant.

关键词： cast-in anchor     concrete cone capacity     geopolymer concrete     head size     surface crack     anchor profile    

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Effect of particle size on coal char----NO reaction

Xiumin JIANG, Xiangyong HUANG, Jiaxun LIU, Chaoqun ZHANG

《能源前沿（英文）》 2011年 第5卷 第2期   页码 221-228 doi: 10.1007/s11708-011-0146-x

摘要： Surface nitrogen complex formation upon reaction of coal char with NO at 600°C was studied by X-ray photoelectron spectroscopy. Particle size had a noticeable effect on the magnitude of changes, which was observed on the surface of the coal char in the nitrogen functional group. The surface increased its -NO, pyridine-N-oxide, and -NO functional group contents with a decrease in particle size. The chemisorption processes of NO molecules on the char were simulated using the ab initio Hartree–Fock method and density functional theory. Molecular modeling was applied to determine the thermodynamics of the reactions. Mechanisms were proposed to explain the formation of the -NO, pyridine-N-oxide, and -NO functional groups at 600°C.

关键词： NO reduction     chemisorption     particle size     X-ray photoelectron spectroscopy     density functional theory (DFT)    

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Soot size distribution in lightly sooting premixed flames of benzene and toluene

Wang LIU, Jiaqi ZHAI, Baiyang LIN, He LIN, Dong HAN

《能源前沿（英文）》 2020年 第14卷 第1期   页码 18-26 doi: 10.1007/s11708-020-0663-6

摘要： The evolution of particle size distribution function (PSDF) of soot in premixed flames of benzene and toluene was studied on a burner stabilized stagnation (BSS) flame platform. The cold gas velocities were changed to hold the maximum flame temperatures of different flames approximately constant. The PSDFs of all the test flames exhibited a bimodal distribution, i.e., a small-size nucleation mode and a large-size accumulation mode. It was observed that soot nucleation and particle growth in the benzene flame were stronger than those in the toluene flame at short residence times. At longer residence times, the PSDFs of the two flames were similar, and the toluene flame showed a larger particle size distribution range and a higher particle volume fraction than the benzene flame.

关键词： premixed flame     soot     particle size distribution function     benzene     toluene    

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生物质原料的组分选择性拆分-功能经济性利用

陈洪章,邱卫华,王岚

《中国工程科学》 2014年 第16卷 第3期   页码 27-36

摘要：

在充分认知生物质原料在化学成分、结构组成、酶解及发酵性能上的不均一性的基础上，提出“组分选择性拆分-功能经济性利用”的生物质炼制新途径，即最大限度保持生物质大分子原有结构、尽可能激活适于酶解组分的生物活性，同时实现中间产物最大价值化。基于生物质原料特性、转化过程和产品要求的关联，笔者创新性地构建了多条生物质炼制产业链，验证了生物质“组分选择性拆分-功能经济性利用”的生物质炼制工业技术体系的可行性、合理性和可靠性。“组分选择性拆分-功能经济性利用”是突围生物质炼制生物燃料、生物材料和生物化学品的经济技术问题的必由之路。

关键词： 生物炼制     原料不均一性     组分选择性拆分-功能经济性利用     工业技术体系    

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A spectrometer for measuring particle size distributions in the range of 3 nm to 10 μm

Jieqiong LIU,Jingkun JIANG,Qiang ZHANG,Jianguo DENG,Jiming HAO

《环境科学与工程前沿（英文）》 2016年 第10卷 第1期   页码 63-72 doi: 10.1007/s11783-014-0754-x

摘要： A spectrometer combining electrical mobility sizing and aerodynamic sizing was developed to measure aerosol size distributions in the range of 3 nm to 10 μm. It includes three instruments which cover different size ranges (a nano scanning mobility particle sizer (NSMPS, 3 – 60 nm), a regular scanning mobility particle sizer (RSMPS, 40 – 700 nm), and an aerodynamic particle sizer (APS, 550 nm – 10 μm)). High voltage and sheath flow of the NSMPS and RSMPS were supplied using two home-built control boxes. A LabVIEW program was developed for spectrometer automatic operation. A linear inversion method was applied to correct particle multiple charging effects and to integrate data from the three instruments into a wide-range size distribution. Experiments were conducted to compare distributions in the overlap size ranges measured by three instruments. Good agreement between the NSMPS and RSMPS was achieved after correcting for the difference in counting efficiencies of the two particle counters. Aerodynamic size distributions reported by the APS were converted to mobility size distributions by applying an effective density method. Distributions measured by the RSMPS and APS were consistent in the overlap size range of 550 – 700 nm. A full spectrum in the size range of 3 nm to 10 μm was demonstrated by measuring aerosol generated using a mixture of different sized polystyrene latex spheres.

关键词： spectrometer     particle size distribution     electrical mobility     linear inversion     aerodynamic diameter    

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Comparison of analytical procedures for measuring phosphorus content of animal manures in China

null

《农业科学与工程前沿（英文）》 2019年 第6卷 第4期   页码 431-440 doi: 10.15302/J-FASE-2019279

摘要：

The concentration and components of manure phosphorus (P) are key factors determining potential P bioavailability and runoff. The distribution of P forms in swine, poultry and cattle manures collected from intensive and extensive production systems in several areas of China was investigated with sequential fractionation and a simplified two-step (NaHCO -NaOH/EDTA) procedures. The mean total P concentration, determined by the sequential fractionation procedure of intensive swine, poultry and cattle manure, expressed as g·kg , was 14.9, 13.4 and 5.8 g·kg , respectively, and 4.4 g·kg in extensive cattle manure. In intensive swine, poultry and cattle manure about 73%, 74% and 79% of total P, respectively, was bioavailable (i.e., P extracted by H O and NaHCO ) and 78% in extensive cattle manure. The results indicated the relative environmental risk, from high to low, of swine, poultry and cattle manure. There is considerable regional variation in animal manure P across China, which needs to be considered when developing manure management strategies.

关键词： diet phosphorus     manure phosphorus     sequential P fractionation    

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A comparative study of particle size distribution from two oxygenated fuels and diesel fuel

Xiaoyan SHI, Kebin HE, Jie ZHANG, Yongliang MA, Yunshan GE, Jianwei TAN,

《环境科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 30-34 doi: 10.1007/s11783-010-0011-x

摘要： Oxygenated fuels are known to reduce particulate matter (PM) emissions from diesel engines. In this study, 100% soy methyl ester (SME) biodiesel fuel (B100) and a blend of 10% acetal denoted by A-diesel with diesel fuel were tested as oxygenated fuels. Particle size and number distributions from a diesel engine fueled with oxygenated fuels and base diesel fuel were measured using an Electrical Low Pressure Impactor (ELPI). Measurements were made at ten steady-state operational modes of various loads at two engine speeds. It was found that the geometric mean diameters of particles from SME and A-diesel were lower than that from base diesel fuel. Compared to diesel fuel, SME emitted more ultra-fine particles at rated speed while emitting less ultra-fine particles at maximum speed. Ultra-fine particle number concentrations of A-diesel were much higher than those of base diesel fuel at most test modes.

关键词： oxygenated fuel     diesel particulate matter     particle size distribution     biofuel    

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Importance of emulsions in crystallization—applications for fat crystallization

Sandra PETERSEN, K. CHALEEPA, Joachim ULRICH

《化学科学与工程前沿（英文）》 2013年 第7卷 第1期   页码 43-48 doi: 10.1007/s11705-013-1309-6

摘要： Emulsions and crystallization are two independent research topics which normally do not overlap although a combination of the two could be applicable to many areas. Here, the importance of emulsions in the field of fat crystallization is described. Three applications with industrial relevance were chosen for investigation: fat fractionation, the solidification of phase change materials and solid lipid nanoparticles. For fat fractionation and phase change materials, emulsification can be applied as a tool to improve the fat crystallization process, and thus the product quality of the crystallized fat. Furthermore, the use of emulsification creates new application fields such as solid lipid nanoparticles in the area of fat crystallization.

关键词： emulsion     fat crystallization     phase change material     emulsion fractionation     emulsion solidification    

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Mechanical properties of rock materials with related to mineralogical characteristics and grain size

Wenjuan SUN, Linbing WANG, Yaqiong WANG

《结构与土木工程前沿（英文）》 2017年 第11卷 第3期   页码 322-328 doi: 10.1007/s11709-017-0387-9

摘要： Mechanical properties of rock materials are related to textural characteristics. The relationships between mechanical properties and textural characteristics have been extensively investigated for differently types of rocks through experimental tests. Based on the experimental test data, single- and multiple- variant regression analyses are conducted among mechanical properties and textural characteristics. Textural characteristics of rock materials are influenced by the following factors: mineral composition, size, shape, and spatial distribution of mineral grains, porosity, and inherent microcracks. This study focuses on the first two: mineral composition and grain size. ? This study comprehensively summarizes the regression equations between mechanical properties and mineral content and the regression equations between mechanical properties and grain size. Further research directions are suggested at the end of this study.

关键词： Mechanical properties     rock material     texture     mineral characteristics    

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标题 作者 时间 类型 操作

Continuous size fractionation of magnetic nanoparticles by using simulated moving bed chromatography

Carsten-Rene Arlt, Dominik Brekel, Stefan Neumann, David Rafaja, Matthias Franzreb

期刊论文

Variation in humic and fulvic acids during thermal sludge treatment assessed by size fractionation, elementary

Yuning YANG,Huan LI,Jinyi LI

期刊论文

The size distribution of airborne bacteria and human pathogenic bacteria in a commercial composting plant

期刊论文

Particle size distribution and shape control of Au nanoparticles used for particle gun

S. Kida, M. Ichiji, J. Watanabe, I. Hirasawa

期刊论文

A better way to do small-for-size liver transplantation in rats

null

期刊论文

Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

期刊论文

Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

期刊论文

Effect of particle size on coal char----NO reaction

Xiumin JIANG, Xiangyong HUANG, Jiaxun LIU, Chaoqun ZHANG

期刊论文

Soot size distribution in lightly sooting premixed flames of benzene and toluene

Wang LIU, Jiaqi ZHAI, Baiyang LIN, He LIN, Dong HAN

期刊论文

生物质原料的组分选择性拆分-功能经济性利用

陈洪章,邱卫华,王岚

期刊论文

A spectrometer for measuring particle size distributions in the range of 3 nm to 10 μm

Jieqiong LIU,Jingkun JIANG,Qiang ZHANG,Jianguo DENG,Jiming HAO

期刊论文

Comparison of analytical procedures for measuring phosphorus content of animal manures in China

null

期刊论文

A comparative study of particle size distribution from two oxygenated fuels and diesel fuel

Xiaoyan SHI, Kebin HE, Jie ZHANG, Yongliang MA, Yunshan GE, Jianwei TAN,

期刊论文

Importance of emulsions in crystallization—applications for fat crystallization

Sandra PETERSEN, K. CHALEEPA, Joachim ULRICH

期刊论文

Mechanical properties of rock materials with related to mineralogical characteristics and grain size

Wenjuan SUN, Linbing WANG, Yaqiong WANG

期刊论文