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Magnetic-porous microspheres with synergistic catalytic activity of small-sized gold nanoparticles andtitania matrix

Kadriye Özlem Hamaloğlu, Ebru Sağ, Çiğdem Kip, Erhan Şenlik, Berna Saraçoğlu Kaya, Ali Tuncel

《化学科学与工程前沿（英文）》 2019年 第13卷 第3期   页码 574-585 doi: 10.1007/s11705-019-1799-y

摘要： Fe O nanoparticles immobilized on porous titania in micron-size range were decorated with small-sized gold nanoparticles and used as a plasmonic catalyst for the reduction of 4-nitrophenol. Monodisperse-porous magnetic titania microspheres were synthesized with bimodal pore-size distribution by the sol-gel templating method. Small-sized gold nanoparticles obtained by the Martin method were attached onto the aminated form of the magnetic titania microspheres. A significant enhancement in the catalytic activity was observed using the gold nanoparticle-decorated magnetic titania microspheres compared to gold nanoparticle-decorated magnetic silica microspheres because of the synergistic effect between small-sized gold nanoparticles and titania. The synergistic effect for gold nanoparticle-attached magnetic titania microspheres could be explained by surface plasmon resonance-induced transfer of hot electrons from gold nanoparticles to the conduction band of titania. Using the proposed catalyst, 4-nitrophenol could be converted to 4-aminophenol in an aqueous solution within 0.5 min. The 4-nitrophenol reduction rates were 2.5–79.3 times higher than those obtained with similar plasmonic catalysts. The selection of micron-size, magnetic, and porous titania microspheres as a support material for the immobilization of small-sized gold nanoparticles provided a recoverable plasmonic catalyst with high reduction ability.

关键词： small-sized gold nanoparticles     magnetic titania microspheres     sol-gel template synthesis     plasmonic catalysis     4-nitrophenol    

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Protein microspheres for pulmonary drug delivery

Yongda SUN,

《化学科学与工程前沿（英文）》 2010年 第4卷 第1期   页码 82-86 doi: 10.1007/s11705-009-0307-1

摘要： A new supercritical fluid (SCF) technique was developed for the preparation of microspheres for pulmonary drug delivery (PDD). This technique, based on the anti-solvent process, has incorporated advanced engineering design features to enable improved control of the particle formation process. Human recombinant insulin (HRI) was used as a model compound to evaluate the efficiency of this SCF process. An aqueous solution of HRI with a co-solvent was sprayed into high pressure carbon dioxide that extracted the solvent and water, leading to a dry fine powder with good particle size distribution and near ideal morphology for pulmonary drug delivery.

关键词： advanced engineering     improved     pressure     aqueous     technique    

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Fabrication of titania thin film with composite nanostructure and its ability to photodegrade rhodamine

ZHANG Gaojie, WU Jinming, LIU Shaoguang, YAN Mi

《化学科学与工程前沿（英文）》 2008年 第2卷 第1期   页码 44-48 doi: 10.1007/s11705-008-0001-8

摘要： A titania nanorod film was synthesized by direct oxidation of metallic Ti with hydrogen peroxide solution under a low temperature. Titania nanoparticles were then filled into the gaps among the nanorods through an infiltration sol-gel procedure to form a composite titania film with an ordered nanostructure. X-ray diffraction spectra indicate that the composite film was a mixture of anatase and rutile while the titania film obtained by only using a sol-gel procedure was pure anatase. Field emission scanning electron microscopy observations show that titania nanoparticles were embedded into the titania nanorod film. Photoluminescence spectra suggest the enhanced separation of electron and hole pairs for the obtained composite titania film over the corresponding titania nanorod film. The composite titania film exhibited improved ability to photodegrade rhodamine B in water compared with the titania nanorod film. The apparent photodegradation rate constant, fitting a pseudo-first-order, was 3 times of that obtained by the sol-gel derived titania film at the same weight. The improved photocatalytic activity for the composite titania film could be attributed to the enhanced separation of electron and hole pairs due to the embedding of the titania nanoparticles within the titania nanorods.

关键词： constant     weight     apparent photodegradation     hydrogen     nanorod    

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A novel cryogenic insulation system of hollow glass microspheres and self-evaporation vapor-cooled shield

Jianpeng ZHENG, Liubiao CHEN, Ping WANG, Jingjie ZHANG, Junjie WANG, Yuan ZHOU

《能源前沿（英文）》 2020年 第14卷 第3期   页码 570-577 doi: 10.1007/s11708-019-0642-y

摘要： Liquid hydrogen (LH ) attracts widespread attention because of its highest energy storage density. However, evaporation loss is a serious problem in LH storage due to the low boiling point (20 K). Efficient insulation technology is an important issue in the study of LH storage. Hollow glass microspheres (HGMs) is a potential promising thermal insulation material because of its low apparent thermal conductivity, fast installation (Compared with multi-layer insulation, it can be injected in a short time.), and easy maintenance. A novel cryogenic insulation system consisting of HGMs and a self-evaporating vapor-cooled shield (VCS) is proposed for storage of LH . A thermodynamic model has been established to analyze the coupled heat transfer characteristics of HGMs and VCS in the composite insulation system. The results show that the combination of HGMs and VCS can effectively reduce heat flux into the LH tank. With the increase of VCS number from 1 to 3, the minimum heat flux through HGMs decreases by 57.36%, 65.29%, and 68.21%, respectively. Another significant advantage of HGMs is that their thermal insulation properties are not sensitive to ambient vacuum change. When ambient vacuum rises from 10 Pa to 1 Pa, the heat flux into the LH tank increases by approximately 20%. When the vacuum rises from 10 Pa to 100 Pa, the combination of VCS and HGMs reduces the heat flux into the tank by 58.08%–69.84% compared with pure HGMs.

关键词： liquid hydrogen storage     hollow glass microspheres (HGMs)     self-evaporation vapor-cooled shield (VCS)     thermodynamic optimization    

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Recent research and development of PLGA/PLA microspheres/nanoparticles: A review in scientific and industrial

Feng Qi, Jie Wu, Hao Li, Guanghui Ma

《化学科学与工程前沿（英文）》 2019年 第13卷 第1期   页码 14-27 doi: 10.1007/s11705-018-1729-4

摘要： Poly(D,L-lactic-co-glycolic acid) (PLGA)/poly(lactic acid) (PLA) microspheres/nanoparticles are one of the most successful drug delivery systems (DDS) in lab and clinic. Because of good biocompatibility and biodegradability, they can be used in various areas, such as long-term release system, vaccine adjuvant, tissue engineering, etc. There have been 15 products available on the US market, but the system still has many problems during development and manufacturing, such as wide size distribution, drug stability issues, and so on. Recently, many new and modified methods have been developed to overcome the above problems. Some of the methods are easy to scale up, and have been available on the market to achieve pilot scale or even industrial production scale. Furthermore, the relevant FDA guidance on the DDS is still incomplete, especially for abbreviated new drug application. In this review, we present some recent achievement of the PLGA/PLA microspheres/nanoparticles, and discuss some promising manufacturing methods. Finally, we focus on the current FDA guidance on the DDS. The review provides an overview on the development of the system in pharmaceutical industry.

关键词： PLGA     microspheres     drug delivery system     stability     manufacturing    

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Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

《机械工程前沿（英文）》 2008年 第3卷 第2期   页码 222-225 doi: 10.1007/s11465-008-0028-z

摘要： The magnetic leakage field distribution resulting from linear defects of a tube sample in the geomagnetic field is modeled according to the magnetic dipole theory. The formula to compute the normal component of the weak magnetic field is deduced based on the spatial distribution of the magnetic dipole. The shape and characteristics of the zero line (an important criterion for magnetic memory testing) of the normal field is analyzed under different longitudinal magnetizations. Results show that the characteristics of the zero line should be considered when the metal magnetic memory testing method is used to find and locate the defect.

关键词： geomagnetic     theory     important criterion     magnetic leakage     normal component    

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Facile preparation of polybenzoxazine-based carbon microspheres with nitrogen functionalities: Effects

Uthen Thubsuang, Suphawadee Chotirut, Apisit Thongnok, Archw Promraksa, Mudtorlep Nisoa, Nicharat Manmuanpom, Sujitra Wongkasemjit, Thanyalak Chaisuwan

《化学科学与工程前沿（英文）》 2020年 第14卷 第6期   页码 1072-1086 doi: 10.1007/s11705-019-1899-8

摘要： In this study, polybenzoxazine (PBZ)-based carbon microspheres were prepared via a facile method using a mixture of formaldehyde (F) and dimethylformamide (DMF) as the solvent. The PBZ microspheres were successfully obtained at the F/DMF weight ratios of 0.4 and 0.6. These microspheres exhibited high nitrogen contents after carbonization. The microstructures of all the samples showed an amorphous phase and a partial graphitic phase. The porous carbon with the F/DMF ratio of 0.4 showed significantly higher specific capacitance (275.1 F g ) than the reference carbon (198.9 F g ) at 0.05 A g . This can be attributed to the synergistic electrical double-layer capacitor and pseudo-capacitor behaviors of the porous carbon with the F/DMF ratio of 0.4. The presence of nitrogen/oxygen functionalities induced pseudo-capacitance in the microspheres, and hence increased their total specific capacitance. After activation with CO , the specific surface area of the carbon microspheres with the F/DMF ratio of 0.4 increased from 349 to 859 m g and the specific capacitance increased to 424.7 F g . This value is approximately two times higher than that of the reference carbon. The results indicated that the F/DMF ratio of 0.4 was suitable for preparing carbon microspheres with good supercapacitive performance. The nitrogen/oxygen functionalities and high specific surface area of the microspheres were responsible for their high capacitance.

关键词： PBZ     carbon     porous materials     microsphere     supercapacitor    

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Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 298-304 doi: 10.1007/s11705-009-0019-6

摘要： We investigated the effect of HMT (hexamethylenetetraamine) on the anodic growth of TiO nanotube arrays. The tube length increases to 4.3 μm with HMT concentration increasing to 0.04 mol·L . Adsorption of HMT on the TiO surface is shown to markedly decrease the chemical dissolution rate of tube mouth, resulting in longer nanotube length. Furthermore, Pt nanoparticles were successfully deposited on the surface of TiO nanotubes by ac electrodeposition method. The TiO /Pt composites were characterized by field emission scanning electron microscope (FESEM), X-ray photoelectron spectra (XPS), and photoelectrochemistry. An enhancement in photocurrent density has been achieved upon modification of TiO nanotubes with Pt nanoparticles.

关键词： TiO2 nanotube arrays     HMT     TiO2/Pt     Photocurrent density    

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Transition metal doped mesoporous titania with a crystalline framework as catalysts for oxidation of

YANG Zehui, OU Encai, WANG Yunan, PENG Li, WANG Jiaqiang, YIN Lihui

《化学科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 296-300 doi: 10.1007/s11705-008-0044-x

摘要： Transition metal M (M = Mn, Fe, Co, Ni, Cu, and Zn) doped mesoporous titania with a crystalline framework was employed as catalysts for the oxidation of -bromotoluene (PBT) to -bromobenzaldehyde (BBD) in acetic acid using aqueous hydrogen peroxide as oxidant. It was found that mesoporous TiO doped with those metals (Fe, Co and Ni) whose atomic radii are relatively smaller exhibited higher conversion rate of PBT. Among these catalysts, the Co/meso-TiO exhibited high substrate conversion and good product (-bromobenzaldehyde) selectivity plus it can be reused once with almost the same activity. The effect of different Ti/Co (molar) ratio on the activities of Co/meso-TiO was also investigated.

关键词： selectivity     conversion     -bromobenzaldehyde     aqueous hydrogen     oxidation    

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Pd nano-catalyst supported on biowaste-derived porous nanofibrous carbon microspheres for efficient catalysis

《化学科学与工程前沿（英文）》 2023年 第17卷 第9期   页码 1289-1300 doi: 10.1007/s11705-023-2299-7

摘要： Environmental pollution caused by the presence of aromatic aldehydes and dyes in wastewater is a serious global concern. An effective strategy for the removal of these pollutants is their catalytic conversion, possibly to valuable compounds. Therefore, the design of efficient, stable and long-lifetime catalysts is a worthwhile research goal. Herein, we used nanofibrous carbon microspheres (NCM) derived from the carbohydrate chitin present in seafood waste, and characterized by interconnected nanofibrous networks and N/O-containing groups, as carriers for the manufacture of a highly dispersed, efficient and stable Pd nano-catalyst (mean diameter ca. 2.52 nm). Importantly, the carbonised chitin’s graphitized structure, defect presence and large surface area could promote the transport of electrons between NCM and Pd, thereby endowing NCM supported Pd catalyst with high catalytic activity. The NCM supported Pd catalyst was employed in the degradation of some representative dyes and the chemoselective hydrogenation of aromatic aldehydes; this species exhibited excellent catalytic activity and stability, as well as applicability to a broad range of aromatic aldehydes, suggesting its potential use in green industrial catalysis.

关键词： biowaste chitin     nanofibrous     palladium     nano-catalyst     catalysis    

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Formation of CaCO hollow microspheres in carbonated distiller waste from Solvay soda ash plants

《化学科学与工程前沿（英文）》   页码 1659-1671 doi: 10.1007/s11705-022-2173-z

摘要： For decades, distiller waste and CO2 were not the first choice for production of high valued products. Here, CaCO3 hollow microspheres, a high-value product was synthesized from such a reaction system. The synthetic methods, the formation mechanism and operational cost were discussed. When 2.5 L·min–1·L–1 CO2 was flowed into distiller waste (pH = 11.4), spheres with 4–13 μm diameters and about 2 μm shell thickness were obtained. It is found that there is a transformation of CaCO3 particles from solid-cubic nuclei to hollow spheres. Firstly, the Ca(OH)2 in the distiller waste stimulated the nucleation of calcite with a non-template effect and further maintained the calcite form and prevented the formation of vaterite. Therefore, in absence of auxiliaries, the formation of hollow structures mainly depended on the growth and aging of CaCO3. Studies on the crystal morphology and its changes during the growth process point to the inside–out Ostwald effect in the formation of hollow spheres. Change in chemical properties of the bulk solution caused changes in interfacial tension and interfacial energy, which promoted the morphological transformation of CaCO3 particles from cubic calcite to spherical clusters. Finally, the flow process for absorption of CO2 by distiller waste was designed and found profitable.

关键词： distiller waste     CO2     hollow microsphere     CaCO3     Ca(OH)2     inside−out Ostwald effect    

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Sulfate digestion process for high purity TiO

T. A. LASHEEN

《化学科学与工程前沿（英文）》 2009年 第3卷 第2期   页码 155-160 doi: 10.1007/s11705-009-0005-z

摘要： A titania slag product of Rosetta ilmenite assaying 72% TiO is treated by the sulfate process option of the pigmentary TiO manufacture. The relevant factors of acid concentration, particle size, slag/acid ratio besides the reaction temperature, and time have been studied. After dissolving the cured mass in dilute acid and clarification, the obtained solution was subjected to hydrolysis of its titanium content. The final product was bleached under reducing conditions to redissolve the residual coloring impurities before being dewatered and calcinated. The obtained results indicated that a leaching efficiency of about 92% was realized due to the presence of some refractory components in the working slag material, namely, rutile and magnesium iron titanate. The obtained white pigment assay attained up to 99.85% TiO , while the analyzed impurities involve 77 ppm Mn and only 14 and 7 ppm of total iron and V, respectively.

关键词： titania     slag     sulfate process     pigment    

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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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Magnetostriction varieties and stress relief caused by pulsed magnetic field

Zhipeng CAI, Xinjie DUAN, Jian LIN, Haiyan ZHAO

《机械工程前沿（英文）》 2011年 第6卷 第3期   页码 354-358 doi: 10.1007/s11465-011-0123-4

摘要：

Magnetostriction is investigated to evaluate the stress relief caused by pulsed magnetic field treatment, because this physical property is closely associated with residual stress. Magnetostriction of different stressed samples is measured in this paper. The stress variations caused by pulsed magnetic treatment are also compared. It is found that magnetostriction variations are closely associated with stress changes. Thermodynamic potential is used to find the relationship between them. Based on several assumptions, we find that the product of magnetostriction amplitude and stress magnitude is nearly a constant during magnetic field treatment, which is valuable for stress relief evaluation and optimizing processing parameters. This conclusion is testified by stress measurements, and the calculated values are in accordance with the experiment results.

关键词： magnetostriction     pulsed magnetic field treatment     stress relief    

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Synergistic scale inhibition of polyaspartic acid composite with magnetic field

LIU Zhenfa, WANG Yanji, GAO Yuhua, ZHANG Lihui

《化学科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 261-265 doi: 10.1007/s11705-007-0047-z

摘要： Polyaspartic acid (PASP) composite, a scale inhibitor, was prepared from PASP, itaconic acid–acrylic acid–acrylic ester (IA-AA-AE) terpolymer and 2-phosphonobutane- 1,2,4-tricarboxylic acid (PBTCA). The scale inhibition of PASP composite and the effect of its synergism with a magnetic field on scale inhibition were investigated. Calcium carbonate crystals in scale samples were characterized by means of SEM and XRD. The static and dynamic experiments show that the chelating function of PASP composite for Ca can be enhanced by synergism with a magnetic field. Under Ca 650 mg/L, HCO 1,300 mg/L and PASP composite 4 mg/L, the scale inhibition rate of PASP composite in magnetic water can increase by 10% in static state and by 20% in dynamic experiments. Scanning electron microscope (SEM) and X-ray diffraction (XRD) results show that calcite and aragonite can be completely transformed into vaterite by using PASP composite.

关键词： synergism     magnetic     PBTCA     dynamic     acid–acrylic acid–acrylic    

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标题 作者 时间 类型 操作

Magnetic-porous microspheres with synergistic catalytic activity of small-sized gold nanoparticles andtitania matrix

Kadriye Özlem Hamaloğlu, Ebru Sağ, Çiğdem Kip, Erhan Şenlik, Berna Saraçoğlu Kaya, Ali Tuncel

期刊论文

Protein microspheres for pulmonary drug delivery

Yongda SUN,

期刊论文

Fabrication of titania thin film with composite nanostructure and its ability to photodegrade rhodamine

ZHANG Gaojie, WU Jinming, LIU Shaoguang, YAN Mi

期刊论文

A novel cryogenic insulation system of hollow glass microspheres and self-evaporation vapor-cooled shield

Jianpeng ZHENG, Liubiao CHEN, Ping WANG, Jingjie ZHANG, Junjie WANG, Yuan ZHOU

期刊论文

Recent research and development of PLGA/PLA microspheres/nanoparticles: A review in scientific and industrial

Feng Qi, Jie Wu, Hao Li, Guanghui Ma

期刊论文

Modeling and analysis of magnetic dipoles in weak magnetic field

WANG Zhaoxia, ZHANG Weimin, LIU Hongguang

期刊论文

Facile preparation of polybenzoxazine-based carbon microspheres with nitrogen functionalities: Effects

Uthen Thubsuang, Suphawadee Chotirut, Apisit Thongnok, Archw Promraksa, Mudtorlep Nisoa, Nicharat Manmuanpom, Sujitra Wongkasemjit, Thanyalak Chaisuwan

期刊论文

Efficient synthesis of titania nanotubes and enhanced photoresponse of Pt decorated TiO

Yuxin YIN, Xin TAN, Feng HOU, Lin ZHAO

期刊论文

Transition metal doped mesoporous titania with a crystalline framework as catalysts for oxidation of

YANG Zehui, OU Encai, WANG Yunan, PENG Li, WANG Jiaqiang, YIN Lihui

期刊论文

Pd nano-catalyst supported on biowaste-derived porous nanofibrous carbon microspheres for efficient catalysis

期刊论文

Formation of CaCO hollow microspheres in carbonated distiller waste from Solvay soda ash plants

期刊论文

Sulfate digestion process for high purity TiO

T. A. LASHEEN

期刊论文

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

Magnetostriction varieties and stress relief caused by pulsed magnetic field

Zhipeng CAI, Xinjie DUAN, Jian LIN, Haiyan ZHAO

期刊论文

Synergistic scale inhibition of polyaspartic acid composite with magnetic field

LIU Zhenfa, WANG Yanji, GAO Yuhua, ZHANG Lihui

期刊论文