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波粒二象性 3

粒子群优化 3

烟颗粒 2

粒子群优化算法 2

Fe、Co、Ru 碳化物 1

Hilare 机器人 1

Pickering乳液 1

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二维纳米颗粒 1

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信息素 1

充电模式;充电时长;随机森林;长短期记忆网络(LSTM);简化粒子群优化算法(SPSO) 1

光催化 1

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全比尺模型试验 1

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Particle formation of hydroxyapatite precursor containing two components in a spray pyrolysis process

W. Widiyastuti, Adhi Setiawan, Sugeng Winardi, Tantular Nurtono, Heru Setyawan

《化学科学与工程前沿(英文)》 2014年 第8卷 第1期   页码 104-113 doi: 10.1007/s11705-014-1406-1

摘要: The particle formation mechanism of hydroxyapatite precursor containing two components, Ca(OOCCH ) and (NH ) HPO with a ratio of Ca/P= 1.67, in a spray pyrolysis process has been studied by computational fluid dynamics (CFD) simulation on the transfer of heat and mass from droplets to the surrounding media. The focus included the evaporation of the solvent in the droplets, a second evaporation due to crust formation, the decomposition reaction of each component of the precursor, and a solid-state reaction that included the kinetic parameters of the precursor regarding its two components that formed the hydroxyapatite product. The rate of evaporation and the reacted fraction of the precursor both increased with temperature. The predicted average size of the hydroxyapatite particles agreed well with the experimental results. Therefore, the selected models were also suitable for predicting the average size of particles that contain two components in the precursor solution.

关键词: droplet     hydroxyapatite particle     CFD     tubular furnace     spray pyrolysis    

Effects of molecular weight and concentration of carboxymethyl cellulose on morphology of hydroxyapatite

Ruiqiang LIU,Rattan LAL

《环境科学与工程前沿(英文)》 2015年 第9卷 第5期   页码 804-812 doi: 10.1007/s11783-015-0785-y

摘要: Nano-sized apatite particles (nAP) synthesized with carboxymethyl cellulose (CMC) have shown great application potentials in in situ heavy metal remediation. However, differences in CMC’s properties effects on the size of nAP produced are not well understood. In this paper, two types of CMC, with respective molecular weights (MW) of ~120000 and ~240000 Dalton or respective polymerization degrees of 500 (CMC-500) and 1050 (CMC-1050), were studied in a concentration range of 0.05%–0.5% (w/w) for nAP synthesis. Morphology of the particles was characterized with transmission electron microscopy (TEM). Results showed that 0.05% CMC-500 solution gave an average particle size of 148.7±134.9 nm, 0.25% CMC-500 solution produced particles of 21.8±20.4 nm, and, 0.5% CMC-500 solution contained particles of 15.8±7.7 nm. In comparison, 0.05% CMC-1050 solution produced nanoparticles of 6.8±3.2 nm, 0.25% CMC-1050 produced smaller nAP of 4.3±3.2 nm, and 0.5% CMC-1050 synthesized the smallest nanoparticles in this study, with an average diameter of 3.0±2.1 nm. Chemical composition of the products was identified with X-ray diffraction (XRD) as pure hydroxyapatite. Interactions between nAP and CMC were discussed with help of attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopic data. This study showed that CMC at higher concentration as well as higher MW facilitated to produce finer nanoparticles, showing that nAP size could be manipulated by selecting appropriate CMC MW and/or applying appropriate CMC concentration.

关键词: nanotechnology     nanoparticles     apatite     carboxymethyl cellulose (CMC)     particle size    

Biomimetic mineralization and cytocompatibility of nanorod hydroxyapatite/graphene oxide composites

Peizhen Duan, Juan Shen, Guohong Zou, Xu Xia, Bo Jin

《化学科学与工程前沿(英文)》 2018年 第12卷 第4期   页码 798-805 doi: 10.1007/s11705-018-1708-9

摘要: Nanorod hydroxyapatite (NRHA)/graphene oxide (GO) composites with weight ratios of 0.4, 1.5, and 5 have been fabricated by a facile ultrasonic-assisted method at room temperature and atmospheric pressure. The chemical structure properties and morphology of the composites were characterized by field emission source scanning electron microscope, X-ray diffraction, transmission electron microscopy, and high-resolution transmission electron microscopy. The results indicate that the NNRHA/GO composites have an irregular surface with different degree wrinkles and are stable, and NRHA are well combined with GO. In addition, the biomimetic mineralization mechanism of hydroxyapatite on the NNRHA/GO composites in simulated body fluid (SBF) is presented. The presence of a bone-like apatite layer on the composite surface indicate that the NNRHA/GO composites facilitate the nucleation and growth of hydroxyapatite crystals in SBF for biomimetic mineralization. Moreover, the NNRHA-1.5/GO composite and pure GO were cultured with MC3T3-E1 cells to investigate the proliferation and adhesion of cells. In vitro cytocompatibility evaluation demonstrated that the NNRHA/GO composite can act as a good template for the growth and adhesion of cells. Therefore, the NNRHA/GO composite could be applied as a GO-based, free-template, non-toxic, and bioactive composite to substitute for a damaged or defect bone.

关键词: hydroxyapatite     graphene oxide     biomimetic mineralization     cytocompatibility    

Nanostructured hollow spheres of hydroxyapatite: preparation and potential application in drug delivery

Xiaojing ZHANG, Weixin ZHANG, Zeheng YANG, Zhao ZHANG

《化学科学与工程前沿(英文)》 2012年 第6卷 第3期   页码 246-252 doi: 10.1007/s11705-012-1299-9

摘要: A solvothermal method has been successfully used to prepare nanostructured hydroxyapatite (HA) hollow spheres with average diameters of about 500 nm and shell thicknesses of about 100 nm in a glycerin/water mixed solvent. Transmission electron microscopy (TEM) and field-emission scanning electron microscopy (FESEM) images show that the shells of the HA hollow spheres are actually composed of nanosheets with thicknesses of about 10 nm. By tuning the glycerin/water volume ratio, two other kinds of HA solid spheres with average diameters of about 6 or 20 μm were assembled from nanoflakes. The properties of the different kinds of spheres as drug delivery carriers were evaluated. Ibuprofen (IBU) was chosen as the model drug to load into the HA samples. The nanostructured HA samples showed a slow and sustained release of IBU. The HA hollow spheres exhibited a higher drug loading capacity and more favorable release properties than the HA solid spheres and thus are very promising for controlled drug release applications.

关键词: hydroxyapatite     hollow spheres     synthesis     drug release    

Removal of lead from aqueous solution by hydroxyapatite/manganese dioxide composite

Lijing DONG,Zhiliang ZHU,Yanling QIU,Jianfu ZHAO

《环境科学与工程前沿(英文)》 2016年 第10卷 第1期   页码 28-36 doi: 10.1007/s11783-014-0722-5

摘要: A novel composite adsorbent, hydroxyapatite/manganese dioxide (HAp/MnO ), has been developed for the purpose of removing lead ions from aqueous solutions. The combination of HAp with MnO is meant to increase its adsorption capacity. Various factors that may affect the adsorption efficiency, including solution pH, coexistent substances such as humic acid and competing cations (Ca , Mg ), initial solute concentration, and the duration of the reaction, have been investigated. Using this composite adsorbent, solution pH and coexistent calcium or magnesium cations were found to have no significant influence on the removal of lead ions under the experimental conditions. The adsorption equilibrium was described well by the Langmuir isotherm model, and the calculated maximum adsorption capacity was 769 mg·g . The sorption processes obeyed the pseudo-second-order kinetics model. The experimental results indicate that HAp/MnO composite may be an effective adsorbent for the removal of lead ions from aqueous solutions.

关键词: lead     composite materials     manganese dioxide     hydroxyapatite     adsorption    

Nano-hydroxyapatite formation via co-precipitation with chitosan-g-poly(

Yang YU, Hong ZHANG, Hong SUN, Dandan XING, Fanglian YAO

《化学科学与工程前沿(英文)》 2013年 第7卷 第4期   页码 388-400 doi: 10.1007/s11705-013-1355-0

摘要: With the excellent biocompatibility and osteoconductivity, nano-hydroxyapatite (nHA) has shown significant prospect in the biomedical applications. Controlling the size, crystallinity and surface properties of nHA crystals is a critical challenge in the design of HA based biomaterials. With the graft copolymer of chitosan and poly( -isopropylacrylamide) in coil and globule states as a template respectively, a novel composite from chitosan-g-poly( -isopropylacrylamide) and nano-hydroxyapatite (CS-g-PNIPAM/nHA) was prepared via co-precipitation. Zeta potential analysis, thermogravimetric analysis and X-ray diffraction were used to identify the formation mechanism of the CS-g-PNIPAM/nHA composite and its morphology was observed by transmission electron microscopy. The results suggested that the physical aggregation states of the template polymer could induce or control the size, crystallinity and morphology of HA crystals in the CS-g-PNIPAM/nHA composite. The CS-g-PNIPAM/nHA composite was then introduced to chitosan-gelatin (CS-Gel) polyelectronic complex and the cytocompatibility of the resulting CS-Gel/composite hybrid film was evaluated. This hybrid film was proved to be favorable for the proliferation of MC 3T3-E1 cells. Therefore, the CS-g-PNIPAM/nHA composite is a potential biomaterial in bone tissue engineering.

关键词: chitosan     poly(N-isopropylacrylamide)     hydroxyapatite     coil     globule     bone tissue engineering    

Best operating conditions to produce hydroxyapatite nanoparticles by means of a spinning disc reactor

A. F. D’ Intino,B. de Caprariis,M.L. Santarelli,N. Verdone,A. Chianese

《化学科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 156-160 doi: 10.1007/s11705-014-1427-9

摘要: In this work, Mg doped hydroxyapatite (Mg-HAP) nanoparticles were produced by a reaction-precipitation process by using a spinning disc reactor (SDR) at high rotational speed. The production process of these nanoparticles consisted of the neutralization reaction between two aqueous solutions of calcium chloride and ammonia orthophosphate at room temperature. By operating at pH= 10, a high purity Mg-HAP nanoparticles were obtained. In particular, they were 51 nm in average size when the two reagents were fed over the disc symmetrically at 3 cm from the disc center and a rotational speed of the disc reactor equal to 1400 r/min was adopted.

关键词: hydroxyapatite     nanoparticles     spinning disc reactor    

Preparation and property of porous hydroxyapatite as an inorganic dispersant used in suspension polymerization

XU Kaqiu, XU Jiale, WANG Yuhong

《化学科学与工程前沿(英文)》 2008年 第2卷 第1期   页码 49-54 doi: 10.1007/s11705-008-0004-5

摘要: The porous hydroxyapatite (HAP) for suspension polymerization dispersant was prepared using calcium carbonate and phosphoric acid as raw materials. The samples were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and BET nitrogen adsorption. The results show that the prepared HAP has a porous structure, low particle density, large specific surface area, uniform particle size and does not agglomerate easily between the particles. The preparation conditions for the HAP were optimized as follows: solid content of calcium carbonate aqueous suspension 90 g/L, concentration of phosphoric acid 1.0 mol/L, reaction/aging temperature 50°C, and aging time 3 h. The HAP prepared under optimal preparation conditions has 106.8 m·g of specific surface area, which is about 1.5–1.8 times as much as that of Japanese HAP or commercial HAP. Its application result in the suspension polymerization of styrene show that the porous HAP dispersant has high surface activity, excellent suspension dispersibility and stability and can markedly improve the quality of polystyrene beads.

关键词: diffraction     stability     nitrogen adsorption     phosphoric     aqueous suspension    

Study on the surface-modification of nano-hydroxyapatite with lignin and the corresponding nanocomposite

Haojie Ding, Liuyun Jiang, Chunyan Tang, Shuo Tang, Bingli Ma, Na Zhang, Yue Wen, Yan Zhang, Liping Sheng, Shengpei Su, Xiang Hu

《化学科学与工程前沿(英文)》 2021年 第15卷 第3期   页码 630-642 doi: 10.1007/s11705-020-1970-5

摘要: To obtain nano-hydroxyapatite/poly(lactide-co-glycolide) (n-HA/PLGA) nanocomposite with superior mechanical properties, here, lignin was chosen to surface-modify for n-HA through co-precipitation method. The different reaction conditions of reaction time, phosphorus source, and the lignin addition amount were studied by fourier transformation infrared spectra, X-ray diffraction, the intuitionistic dispersion experiment, transmission electron microscope and thermal gravimetric analysis. The reaction mechanism and the best appropriate reaction condition were obtained. More importantly, the results of electromechanical universal tester, scanning electron microscope, differential scanning calorimetric analyzer, polarized optical microscopy and dynamic mechanical analysis confirmed that the obtained n-HA could greatly increase the mechanical strength of PLGA, owing to the excellent dispersion and promotion crystallization effect. Moreover, cell culture experimental results indicated that the n-HA surface-modified by lignin was favorable to improve the cell biocompatibility of PLGA. The study suggested that the introduction of lignin was a novel method to acquire a highly dispersed n-HA, which would provide a new idea to achieve the n-HA/PLGA nanocomposite as bone materials in future, and it would pave the way towards a new application of lignin in biomedical field.

关键词: nanocomposite     poly (lactide-co-glycolide)     hydroxyapatite     mechanical property    

Catalyst particle shapes and pore structure engineering for hydrodesulfurization and hydrodenitrogenation

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 897-908 doi: 10.1007/s11705-021-2127-x

摘要: Catalyst particle shapes and pore structure engineering are crucial for alleviating internal diffusion limitations in the hydrodesulfurization (HDS)/hydrodenitrogenation (HDN) of gas oil. The effects of catalyst particle shapes (sphere, cylinder, trilobe, and tetralobe) and pore structures (pore diameter and porosity) on HDS/HDN performance at the particle scale are investigated via mathematical modeling. The relationship between particle shape and effectiveness factor is first established, and the specific surface areas of different catalyst particles show a positive correlation with the average HDS/HDN reaction rates. The catalyst particle shapes primarily alter the average HDS/HDN reaction rate to adjust the HDS/HDN effectiveness factor. An optimal average HDS/HDN reaction rate exists as the catalyst pore diameter and porosity increase, and this optimum value indicates a tradeoff between diffusion and reaction. In contrast to catalyst particle shapes, the catalyst pore diameter and the porosity of catalyst particles primarily alter the surface HDS/HDN reaction rate to adjust the HDS/HDN effectiveness factor. This study provides insights into the engineering of catalyst particle shapes and pore structures for improving HDS/HDN catalyst particle efficiency.

关键词: hydrodesulfurization     hydrodenitrogenation     particle shape     pore structure    

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

《能源前沿(英文)》 2012年 第6卷 第1期   页码 89-97 doi: 10.1007/s11708-012-0176-z

摘要: This paper discusses two problems in in-line particle sizing when using light fluctuation method. First, by retrieving the ratio of particle concentrations at different time, the intensity of incident light is obtained. There exists narrow error between the calculated and pre-detected value of the intensity of incident light. Secondly, by combining spectrum analysis with Gregory’s theory, a multi-sub-size zone model is proposed, with which the relationship between the distribution of turbidity and the particle size distribution (PSD) can be established, and an algorithm developed to determine the distribution of turbidity. Experiments conducted in the laboratory indicate that the measured size distribution of pulverized coal conforms well with the imaging result.

关键词: in-line measurement     particle size distribution (PSD)     incident light intensity     particle concentration     light fluctuation    

Development and clinical trial of a novel bioactive bone cement

LEONG John, LI Zhaoyang, LU William

《医学前沿(英文)》 2008年 第2卷 第2期   页码 117-126 doi: 10.1007/s11684-008-0022-1

摘要: Strontium (Sr) and related compounds have become more attractive in the prevention and treatment of osteoporosis. Previously, we developed a novel bioactive bone cement which is mainly composed of strontium-containing hydroxyapatite (Sr-HA) filler and bisphenol A diglycidylether dimethacrylate (Bis-GMA) resin. This bone cement is superior to conventional polymethylmethacrylate (PMMA) bone cement in bioactivity, biocompatibility, and osseointegration. It also has shown sufficient mechanical strength properties for its use in percutaneous vertebroplasty (PVP) and total hip replacement (THR). In this paper, we review the and clinical evidence for the effectiveness of this bioactive bone cement.

关键词: bioactivity     effectiveness     strontium-containing hydroxyapatite     osseointegration     sufficient mechanical    

Independent cover meshless particle method for complex geotechnical engineering

Jianqiu WU, Yongchang CAI

《结构与土木工程前沿(英文)》 2018年 第12卷 第4期   页码 515-526 doi: 10.1007/s11709-017-0428-4

摘要: A new Independent Cover Meshless Particle (ICMP) method is proposed for the analysis of complex geotechnical engineering. In the ICMP method, the independent rectangular cover regardless of the shape of the analysis model is employed as the influence domain of each discrete node, the general polynomial is employed as the meshless interpolation function of the independent nodal cover, and the Cartesian Transformation Method (CTM) is used for the numerical integration of the nodal covers cut by material interfaces, joints, cracks and faults. The present method has a simple formulation and a low computational cost, and is easy for the numerical analysis and modeling of complex geotechnical engineering. Several typical numerical examples are presented to demonstrate the accuracy and robustness of the proposed method.

关键词: meshless method     particle method     independent cover     CTM     geotechnical engineering    

Microdamage study of granite under thermomechanical coupling based on the particle flow code

《结构与土木工程前沿(英文)》   页码 1413-1427 doi: 10.1007/s11709-023-0953-2

摘要: The thermomechanical coupling of rocks refers to the interaction between the mechanical and thermodynamic behaviors of rocks induced by temperature changes. The study of this coupling interaction is essential for understanding the mechanical and thermodynamic properties of the surrounding rocks in underground engineering. In this study, an improved temperature-dependent linear parallel bond model is introduced under the framework of a particle flow simulation. A series of numerical thermomechanical coupling tests are then conducted to calibrate the micro-parameters of the proposed model by considering the mechanical behavior of the rock under different thermomechanical loadings. Good agreement between the numerical results and experimental data are obtained, particularly in terms of the compression, tension, and elastic responses of granite. With this improved model, the thermodynamic response and underlying cracking behavior of a deep-buried tunnel under different thermal loading conditions are investigated and discussed in detail.

关键词: thermomechanical coupling effect     granite     improved linear parallel bond model     thermal property     particle flow code    

Study on direct measurement method of vorticity from particle images

RUAN Xiaodong, FU Xin, YANG Huayong

《能源前沿(英文)》 2007年 第1卷 第4期   页码 408-412 doi: 10.1007/s11708-007-0059-1

摘要: To overcome the shortcomings of conventional methods for vorticity measurement, a new direct measurement of vorticity (DMV) method extracting vorticity from particle images was proposed. Based on the theory of fluid flow, two matc

关键词: conventional     vorticity measurement     particle     DMV     theory    

标题 作者 时间 类型 操作

Particle formation of hydroxyapatite precursor containing two components in a spray pyrolysis process

W. Widiyastuti, Adhi Setiawan, Sugeng Winardi, Tantular Nurtono, Heru Setyawan

期刊论文

Effects of molecular weight and concentration of carboxymethyl cellulose on morphology of hydroxyapatite

Ruiqiang LIU,Rattan LAL

期刊论文

Biomimetic mineralization and cytocompatibility of nanorod hydroxyapatite/graphene oxide composites

Peizhen Duan, Juan Shen, Guohong Zou, Xu Xia, Bo Jin

期刊论文

Nanostructured hollow spheres of hydroxyapatite: preparation and potential application in drug delivery

Xiaojing ZHANG, Weixin ZHANG, Zeheng YANG, Zhao ZHANG

期刊论文

Removal of lead from aqueous solution by hydroxyapatite/manganese dioxide composite

Lijing DONG,Zhiliang ZHU,Yanling QIU,Jianfu ZHAO

期刊论文

Nano-hydroxyapatite formation via co-precipitation with chitosan-g-poly(

Yang YU, Hong ZHANG, Hong SUN, Dandan XING, Fanglian YAO

期刊论文

Best operating conditions to produce hydroxyapatite nanoparticles by means of a spinning disc reactor

A. F. D’ Intino,B. de Caprariis,M.L. Santarelli,N. Verdone,A. Chianese

期刊论文

Preparation and property of porous hydroxyapatite as an inorganic dispersant used in suspension polymerization

XU Kaqiu, XU Jiale, WANG Yuhong

期刊论文

Study on the surface-modification of nano-hydroxyapatite with lignin and the corresponding nanocomposite

Haojie Ding, Liuyun Jiang, Chunyan Tang, Shuo Tang, Bingli Ma, Na Zhang, Yue Wen, Yan Zhang, Liping Sheng, Shengpei Su, Xiang Hu

期刊论文

Catalyst particle shapes and pore structure engineering for hydrodesulfurization and hydrodenitrogenation

期刊论文

A novel light fluctuation spectrum method for in-line particle sizing

Shouxuan QIN, Xiaoshu CAI, Li MA

期刊论文

Development and clinical trial of a novel bioactive bone cement

LEONG John, LI Zhaoyang, LU William

期刊论文

Independent cover meshless particle method for complex geotechnical engineering

Jianqiu WU, Yongchang CAI

期刊论文

Microdamage study of granite under thermomechanical coupling based on the particle flow code

期刊论文

Study on direct measurement method of vorticity from particle images

RUAN Xiaodong, FU Xin, YANG Huayong

期刊论文