MATERIALS SCIENCE FORUM
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2020
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IF 0
Chuan Jun Xia,Ping Deng Ming,Ya Song Hu,Cong Cong Zhan,An Duo Zhou,He Yi Mao,Xia Huang
In the present study, oligopeptide (TEA) and modified Pluronic F127 (M-Pluronic F127) with different mass fraction composited by intermolecular forces. And the oligopeptide/M-Pluronic F127 composite membranes were prepared and investigated. The structural parameters of the membranes were characterized by fourier transform-infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) measurements. It was found that there had strong interaction between TEA and M-Pluronic F127 and the composite films with different proportions had different surface morphology and thermal stability. The characteristics of the membranes were related to the significant changes of the self-assembly behavior of the TEA modified by M-Pluronic F127.
研究领域:
生物材料学
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分子生物学
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DOI
MATERIALS SCIENCE FORUM
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2020
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IF 0
Yu Quan Ren,Shi Yong Sun,Edward Opong Acheampong,Fa Qin Dong,Biao Biao Ma,Ke Wang,Xiao Yu Fan
A one-step synthesis of visible light responsive diatomite/g-C3N4 composite material was prepared by impregnation-calcination method. The products were characterized by Scanning electron microscope, X-ray diffractometer, Ultraviolet diffuse reflectance spectroscopy, Fourier transform infrared spectrometer, and Photoluminescence spectrometer. The SEM results showed that g-C3N4 was successfully attached onto the surface of the diatomite. Also the composite materials were more light-responsive compared with the single phase material. The composite materials had a maximum degradation efficiency up to nearly 91.79%. The significant improvement in photocatalytic performance was due to the porous structure of diatomite, increase of contact area of carbon nitride.
研究领域:
材料科学
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环境科学
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DOI
MATERIALS SCIENCE FORUM
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2020
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IF 0
Fu Liang Jiang,Hong Bo Zhang,Wen Jun Zhang
Microfluidics has great control over the size and uniformity of microspheres, which has been widely used in fabrication of different types of microspheres such as core-shell microbubbles. Gelatin Methacrylate (GelMa) as a biodegradable material that is closely resemble to native extracellular matrix (ECM). Photocrosslinked GelMa microspheres have gained numerous concerns in biomedical applications especially in three-dimensional cell culture and tissue engineering. In this article, we presented a suitable core-shell cell carrier based on biocompatible GelMa microbubbles. Highly monodispersed microbubbles were fabricated using a non-planar flow focusing microfluidic device. Both intact and collapsed microbubbles morphology were characterized through scanning electron microscopy (SEM), where clear hollow structures were found resulting from the gas core collapsing during the manipulation process. Furthermore, human umbilical vein endothelial cells (HUVEC) were seeded in the existence of microbubbles. Cells adhesion, migration and proliferation were observed in one week. It was notable that cells maintained high level of cell viability throughout the experiment. GelMa microbubble surface was also covered with cells, which became a facile carrier for cell culturing and targeted cell delivery.
研究领域:
生物医学工程
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材料科学
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细胞生物学
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DOI
MATERIALS SCIENCE FORUM
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2018
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IF 0
Qin Yu Pei,Rui Wang,Xue Qin Jin,Guo Jing Gou
In this paper, we synthesized a CdHgTe type water-soluble quantum dots, combined in the next time with the drug delivery system "dextran - magnetic layered double hydroxide - fluorouracil" (DMF), built a new nanostructures platform QD@DMF for blending the fluorescent probe function of quantum dot together with the magnetic targeting curative effect of the DMF system. The Fluorescence spectrophotometer, Ultraviolet spectrophotometer, TEM and XRD were used to characterize the luminescent properties, particle morphology and phase characteristics of the QD@DMF samples. The experiments on cell imaging were carried out by laser con-focal scan microscopy technique. Results showed that the CdHgTe QDs could be successfully grafted onto the surface of the DMF system through electrostatic coupling, forming a special structure based on magnetic layered double hydroxide with a near-infrared emission wavelength in 575~780 nm. Compared with QDs, the QD@DMF composite could significantly improve the cell imaging effect, the label intensity increased with the magnetic field intensity and obeyed the linear relationship Dmean = 1.760+0.013B. The fluorescent magnetic nanoparticles maintained not only the super-paramagnetic of DMF but also the photoluminescence properties of the QDs, implicating that the QD@DMF composite may be an effective multifunction tool for optical bio-imaging and magnetic targeted therapy.
✓ 已验证
DOI
MATERIALS SCIENCE FORUM
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2014
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IF 0
Fang Wei Qi,Xue Gang Luo,Xiao Yan Lin
In present study, two kinds of CaCO3 with micro-sized and nanometer-sized particles were treated by pimelic acid (PA) with different proportion. Then the treated particles (the total content of micro-sized and nanometer-sized CaCO3 particles was 10 wt%) were mixed with polypropylene (PP) to prepare CaCO3/PP composites by melting blending. The crystallization behavior and morphology of composites were studied by wide-angle-X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and polarized microscope (PLM), respectively. Compared with PP and other samples, the content of β-crystal in the composite NCP2 where the ratio of nanoand micro particles was 2:8 (NCP2), reached the highest values. The growth speed of crystals in PP matrix was much quicker, leading to the larger spherulites than the NCP2 and NCP8. The time of complete nucleation for NCP8 was lower than PP, but higher than NCP2.
研究领域:
材料科学
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高分子科学
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复合材料
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DOI
MATERIALS SCIENCE FORUM
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2021
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IF 0
Sha Chen,Jing Hua Gong,Jing Hong Ma
Helix is a sophisticated structure in nature and has many unique functions which makes it possible to store more information and energy, even receive more sensitive signals. Besides, as an effective method for preparing hydrogel fibers, microfluidic spinning has achieved unprecedented development in the past decade. However, hydrogel fiber with helical structure has began to be studied only in recent years. In this paper, the helical hydrogel fibers were prepared by the microfluidic spinning method. The microfluidic chip was assembled by PDMS connector, collection tube, inner and outer channels. Sodium alginate (SA) and calcium chloride were used as the core fluid and sheath fluid, respectively. By designing and adjusting the length of the chip, changing the concentration of SA and the ratio of two flow rates (inner flow rate/outer flow rate), a continuous and uniform helical hydrogel fiber was prepared. The relationships between the diameter of the fiber, the pitch of the helix and the concentration of SA, the ratio of two flow rates were discussed. The results showed that the diameter of the fiber was mainly affected by the core fluid. Within a certain range, as the concentration of SA increased, the diameter of the fiber increased. Besides, the pitch of the helix was greatly affected by the flow rate of sheath fluid. As the velocity of the sheath fluid increased, the pitch of the fiber increased. Such helical fiber could be used in micro sensors when added some conductive materials or crosslinked with some temperature responsive polymers such as N-isopropylacrylamide.
研究领域:
材料科学
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生物医学工程
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DOI
MATERIALS SCIENCE FORUM
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2020
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IF 0
Xing Liu,Hong Yuan Xing,Gang Liu,Wei Fu,Wen Bo Zeng
Based on the rheological property master curve, a new definition of ageing index was proposed for styrene-butadiene-styrene block copolymer (SBS) modified bitumen. The UV ageing resistance of the combined-modifier modified SBS bitumen was evaluated. Twelve different methods of combined modification were designed with three kinds of modifiers: ultraviolet absorber (Tinuvin 770), organic montmorillonite (OMMT) and layered double hydroxide (LDHs). With modified SBS bitumen, short-term ageing (TFOT) and laboratory ultraviolet ageing (UV) were performed. The dynamic shear rheometer (DSR) was used to perform frequency sweep test on the samples before and after ageing. The rheological property master curve was obtained by fitting the constitutive model equation. Based on the rheological property master curve, a new definition ageing index was proposed for SBS bitumen to evaluate the modified bitumen with different combined-modifier. The results show that the ageing index could effectively evaluate the UV ageing resistance of SBS bitumen. The evaluation results show that the combined-modifier bitumen exhibits better anti-ultraviolet ageing effects than a single modifier. Among them, the combined-modifier modes of 0.3%Tinuvin770+5%OMMT and 0.6%Tinuvin770+2.5%LDHs performed.
研究领域:
材料科学
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土木工程
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DOI
MATERIALS SCIENCE FORUM
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2021
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IF 0
Fei Han,Xi Ping Xi,Min Fan,Ling Ling Wang,Jin Ming Shi,Qin Liang Jiang,Bo Hong Chen,Heng Yan
In the paper, a novel perovskite microcrystalline with a capsule-free cavity box structure was creatively prepared through solvent thermal reaction, and the composition and structure of CH3NH3PbI3 perovskite microcrystalline were further characterized by scanning electron microscope (SEM) and energy dispersive X-ray (EDX) element mapping. The SEM results show that the grain size of the prepared CH3NH3PbI3 perovskite microcrystalline is more than 100 μm. Furthermore, X-ray diffraction (XRD) analysis was used to characterize the material decomposition of perovskite microcrystals before and after 150 d of air aging. The XRD results indicate the prepared perovskite microcrystalline could be stably preserved in the air for 150 d without degradation. Our method provides technical guidance for further enriching the morphology of CH3NH3PbI3 perovskite microcrystalline.
研究领域:
材料科学
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化学
✓ 已验证
DOI
MATERIALS SCIENCE FORUM
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2016
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IF 0
Chag Ku Ding,Jing De Zhang,Ya Lei Liu,Jin Yan Gou,Jun Peng Luan
A comparative study has been carried out on the effects of pore-forming agents on the microstructural characteristics and properties including porosity, microstructures, linear sintering shrinkage and mechanical strength of NiO/yttria stabilized zirconia (YSZ). Different pore-forming agents (soluble starch, graphite and activated carbon) were incorporated into NiO/YSZ at various mass mixing ratios (5%, 10% and 15%). The experimental results show that under the condition of same content, sintered samples using activated carbon as pore-forming agent had a higher porosity than that with identical content of the other two kinds of pore-forming agents. Sintered samples with 10.0 wt% activated carbon had a porosity of 35%. Section morphologies show that pores distributed uniformly and connected very well in the anode with activated carbon as pore-forming agent. The mechanical strength of these sintered samples with carbon as pore-forming agent was also higher. With the activated carbon particle size decreasing (from 100 mesh to 320 mesh), the open porosity of porous NiO/YSZ was reduced (from 31.7% to 30.9%). It may be concluded that The activated carbon is the better choice as pore-forming agent for NiO/YSZ anode.
研究领域:
材料科学
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燃料电池研究
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DOI
MATERIALS SCIENCE FORUM
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2019
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IF 0
Zhi Min Ou,Jia Ying Pan
In this study, magnetic chitosan microspheres (Fe3O4-CTS) were prepared via chemical co-precipitation and cross-linked with lipase using glutaraldehyde to form Fe3O4-CTS-glutaraldehyde-lipase particles. The textural characteristics of Fe3O4-CTS-glutaraldehyde-lipase particles were assessed by scanning electron microscopy. The optimal immobilization conditions were 2.1 mg/mL lipase, 10 mg/mL Fe3O4-CTS-glutaraldehyde, pH 7.5, 30 °C, 2 h. The loading amount of lipase was 126.0 mg/g carrier, and the specific activity reached to 46.7 U/mg. Fe3O4-CTS-glutaraldehyde-lipase particles was used in resolution of racemic 1-phenylethylamine in a solvent-free system. The conversion and enantiomeric excess of (R)-N-(1-phenylethyl)acetamide reached 33.6% and 97%.
研究领域:
生物催化
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纳米技术
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酶工程
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有机合成
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手性拆分
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DOI
MATERIALS SCIENCE FORUM
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2019
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IF 0
Guang Yu Duan,Zu Ming Hu
A high-temperature poly (m-phenyleneisophthalamide) (PMIA) dielectric composite was successfully manufactured with functionalized BN (fBN) fillers. Due to effective modification by KH-550, fBN particles evenly dispersed in PMIA matrix. The dielectric property, breakdown strength and thermal conductivity of PMIA/fBN dielectric composite were researched. The consequences indicate that fBN fillers can not only decrease the dielectric loss but also enhance the breakdown strength of PMIA/fBN dielectric composites. Furthermore, owing to the generated heat transfer pathways by fBN particles, the thermal conductivities improved from 0.23 W·m-1·K-1 of fBN-0 to 0.86 W·m-1·K-1 of fBN-30, demonstrating a significant improvement. These results present a novel method for fabricating high-temperature PMIA/fBN dielectric composites with improved breakdown strength and thermal conductivity.
研究领域:
材料科学
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电气工程
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聚合物复合材料
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热管理
✓ 已验证
DOI
MATERIALS SCIENCE FORUM
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2016
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IF 0
Yue Ting Li,Hui Qin Lian,Yan Ou Hu,Lei Zu,Xiu Guo Cui,Yang Liu,Yu Peng Liu,Ben Ze Wu
Liquid crystalline polyurethanes (LCPU) were prepared from 4,4’-methylenediphenyl diisocyanate (MDI), 1,6-hexanediol (HDO), 2,2-dimethylol propionic acid (DMPA) and polytetramethylene ether glycol (PTMG). The experiments synthesized three liquid crystalline polyurethane films with different soft/hard segment ratio. Chemical and structural characterization of the polyurethanes were investigated by Fourier transform infrared, X-ray diffraction, thermogravimetric analysis, differential scanning calorimeter and polarized microscopy respectively. Swelling rate and shape memory property were tested. The results indicated that the polyurethane with 62% soft segment and large group of carboxyl displayed excellent swelling and shape memory properties, and the shape recovery rate reached 100%. It was found that the crystallinity, thermal stability decreased and the temperature flexibility, water absorption and shape recovery rate increased with the increase of polytetramethylene ether glycol.
研究领域:
材料科学
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高分子化学
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智能材料
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形状记忆聚合物
✓ 已验证
DOI
危险品化学品经营许可证（带存储）