MATERIALS SCIENCE FORUM
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2019
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IF 0
Mei Ling Zhou,Dan Mei Hu,Yu Jie Shao,Jing Hong Ma,Jing Hua Gong
Temperature-responsive hydrogel fibers with bilayer structure were prepared by a microfluidic spinning device with a Y-shaped connector. The bilayer hydrogel fibers include two layer with different chemical composition. One layer is the ionic crosslinking hydrogel of calcium alginate (CA) and the other layer is temperature-responsive hydrogel which is semi-interpenetrating polymer networks (semi-IPN) of linear poly (N-isopropylacrylamide) (PNIPAM) and CA. The bilayer hydrogel fibers were evaluated by morphology observation, tensile stress measurement, temperature-responsive actuation test and equilibrium swelling ratio test. The results show that the prepared hydrogel fibers have obvious double layer structure with different porous structures. The bilayer hydrogel fibers can bend in water at 50 °C and the bending rate is influenced by the diameter of the fiber. Moreover, the diameter of the hydrogel fibers can be controlled by changing the flow rates of spinning fluids.
研究领域:
材料科学
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高分子科学
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微流控技术
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智能材料
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柔性机器人
✓ 已验证
DOI
MATERIALS SCIENCE FORUM
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2016
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IF 0
Yu Xuan Liang,Peng Peng Bai,Shu Qi Zheng
Pyrite (FeS2) is an important semiconductor material which shows various excellent optical and electrical properties and extensive applied prospect as a new-type, photoelectrical functional materials. In this study, a low cost and efficient simple hydrothermal two-step synthetic method was given to obtain FeS2 microspheres with 2-3 μm in diameter. The obtained products were characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and ultraviolet and visible spectrophotometer (UV-Vis). XRD showed that the synthetic sample consisted of two crystal structures of FeS2, pyrite and marcasite. SEM observation indicated that FeS2 microspheres were well crystallized and had good uniformity. UV-Vis spectrum had a strong optical absorption in the region of 200-400 nm wave length. The reaction temperature had an impact on the size of FeS2 microspheres. A possible mechanism for the size of the FeS2 microspheres generated at high temperature is smaller than that at low temperature is discussed.
研究领域:
材料科学
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纳米技术
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半导体材料
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光电子学
✓ 已验证
DOI
MATERIALS SCIENCE FORUM
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2018
·
IF 0
Wen Qiang Ma,Cheng Jie Deng,Jin Le Lan,Xiao Ping Yang,Yuan Hua Lin
Polycrystalline Bi1-xCuSeO (0 ≤ x ≤ 0.05) ceramics were prepared by self-propagating high-temperature synthesis followed by spark plasma sintering method. All the samples correspond with single BiCuSeO phase and high vacancies sample had higher density. The highest power factor of 4.71×10-4 W.m-1.K-2 was obtained by 5% Bi vacancies at 873K, which is about 32% higher than that of the pristine sample. Along with slight reduction of thermal conductivity, the maximum ZT reached 0.68. The results show that vacancy engineering is a promising method for thermoelectric applications of BiCuSeO and related ceramics.
研究领域:
材料科学
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热电学
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陶瓷工程
✓ 已验证
DOI
MATERIALS SCIENCE FORUM
·
2014
·
IF 0
Hong Ling Li,Xu Duo Bai,Yu Zhu,Yan Qiu Wang,Yu Liang,Hai Jun Niu
4-Phenoxy-4', 4''-diaminotriphenylamine was synthesized from N, N-diarylation of 4-amino diphenyl ether and 4-fluoro nitrobenzene, and subsequent reduction of the resultant dinitro compound. The prepared triphenylamine and 4-methoxy-4', 4''-diaminotriphenylamine were dissolved in acetone respectively as the curing agents with epoxy resins to obtain a homogeneous mixture of the reactants. The cross-linked polymer film, which was well adhered to the ITO glass were cured by gradually increasing the temperature under N2 atmosphere. The cured epoxy resins films exhibited good thermal stability and electroactive properties. CV of the films revealed two pairs of reversible redox peaks, with coloration change from the colorless neutral state to the blue oxidized state.
研究领域:
材料科学
·
高分子化学
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电化学
·
功能材料
✓ 已验证
DOI
MATERIALS SCIENCE FORUM
·
2018
·
IF 0
De Zhi Wang,Yu Qing Zhang,Bo Hua Duan
In this work, Molybdenum trioxide and conventional copper particles were used as precursors, reduced in hydrogen atmosphere. Then Cu@Mo Powders were successfully synthesized. Effects of reduction temperature on the microstructure of the composite powders and the performance of the intermediate product (molybdenum dioxide) were investigated. Results show that 700°C is the optimal reduction temperature, because Mo is reduced from its oxide and forms a coating layer on the surface of copper particles tightly without serious crack. Mo-20wt.% Cu composite powders where Cu is coated uniformly with continuous molybdenum layer are successfully obtained by co-reduction method.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
MATERIALS SCIENCE FORUM
·
2018
·
IF 0
Miao Ying Jin,Shi Yan Chen,Bao Xiu Wang,Hua Ping Wang
Wound healing is accompanied by keloids, it is important to develop a wound dressing which can inhibit keloid and relieve pain and pruritus in patients. In this paper, bacterial cellulose/triamcinolone acetonide (BC/TA) composites are prepared by easy solution impregnation method, which the structures of BC/TA composites were analyzed by fourier transform infrared spectroscopy (FTIR). The drug release and inhibition of L929 cells were also analyzed. It can be concluded that BC/TA composites have a sustained release effect on TA and can effectively inhibit proliferation of L929 in the range of 0.5-2.0 mg/cm2.
研究领域:
生物医学工程
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药理学
✓ 已验证
产品关联
DOI
MATERIALS SCIENCE FORUM
·
2018
·
IF 0
Rui Min Zhao,Xian Ya Xue,You Fa Wang
Porous Hyaluronan/β-tricalcium phosphate composite scaffolds were synthesized through lyophilizing and subsequent heterogeneous crosslinking method. The morphology of the composite scaffolds were investigated by scanning electron microscopy (SEM). The swelling behavior, mechanical property, degradation behavior and cell adhesion ability of samples were also studied. The results revealed that hyaluronan mainly contributed to the polymer matrix and water adsorption, whereas β-TCP acted as a reinforcement to strengthen the porous structure, while too much β-TCP would make the structure collapse. The pose size of obtained scaffolds ranges from100μm to 200μm and the porosity decreased with the increase of β-TCP content. The degradation behavior and cell adhesion test indicated that increasing hyaluronan concentration can effectively improve the degradability of scaffolds and the incorporation of β-TCP improved the cell adhesion performance. Thus a simple way to prepare hyaluronan-based composite scaffolds was provided, which could be potentially used as an tissue engineering material.
研究领域:
生物材料
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组织工程
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生物医学工程
✓ 已验证
产品关联
DOI
MATERIALS SCIENCE FORUM
·
2019
·
IF 0
Fuchun Zhao,Jie Guan,Wan Na Bai,Shuang Quan Liao
The quality stability of the natural rubber is a key point to its use in the industries and some special fields. However, due to storage hardening caused by the complicated molecular structure of natural rubber and non-rubber component, the quality uniformity is still not controlled in the nowadays rubber factory. In the previous research, storage hardening phenomena are extensively examined but the special mechanism is controversial and detail information is need to be further revealed. The dynamic evolution of accelerated storage properties and molecular structure of natural rubber have been investigated. The results show that △P increased slowly at first but then increased apparently and PRI has no direct relationship with △P. The storage time of 24 h is the critical storage period in which besides the △P and PRI, the P0, gel content and molecular weight also has obvious transformation. △P has a negative apparent correlation with ester content but protein content is relatively of no account in storage hardening process.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
MATERIALS SCIENCE FORUM
·
2019
·
IF 0
Yong Li Peng,Can Zhang,Ni An Zhuo
Using 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10 oxide (DOPO) and N-methylol acrylamide as the main raw materials, the curing agent DOPO-NMA was synthesized. The flame retardant curing agent DOPO-NMA and E-51 epoxy resin (EP) were then cured to obtain epoxy resin E-51 system, and its flame retardancy, thermal stability and mechanical properties were studied. The results showed that the tensile, bending and impact strength of the cured system decreased with the increase of phosphorus mass fraction in the resin system, and the flame retardancy rating, limiting oxygen index (LOI) and char yield at 700°C increased with the increase of phosphorus mass fraction in the resin system.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
MATERIALS SCIENCE FORUM
·
2019
·
IF 0
Ji Fu Du,Zhen Dong,Xin Yang,Long Zhao
Glycidyl methacrylate (GMA) was grafted onto the surface of HDPE particles by radiation grafting and emulsion graft copolymerization. And subsequent ring-opening reaction of expoxy groups in poly-GMA graft chains with N-methylglucamine (NMG) was conducted to synthesis the boron adsorbent. The synthesis condition (radiation dose and NMG concentration) was optimized and characterized by IR and SEM. Adsorption behaviors of the boron adsorbent for boron removal presented that adsorption kinetics was well described by pseudo-second-order kinetic mode. The adsorption isothermal was well fitted with both Langmuir and Freundlich isotherm models. The adsorption capacity for boron reached 15.63 mg/g at optimal pH 8. Dynamic experiment revealed that boron could be efficiently adsorbed by the boron adsorbent and fully desorbed using 13 BV of 1 mol/L HCl.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
MATERIALS SCIENCE FORUM
·
2019
·
IF 0
Kai Bo Pan,Jing An,Bi Zhen Yuan,Xiao Dan Lv,Xiu Hua Huang,Bai Yang,Zhan Chen Cui
Fluorescent detection is a practical kind of methods to use in heavy metal ions detection technology. Carbonized Polymer Dots (CPDs) is good carbon-like material with low toxicity, green, ion-response. In this work, we successfully synthesized a yellowing fluorescent CPDs from folic acid. The luminescence intensity of CPDs decreased with the increase of copper ion content, and the detection limit was 0.44ppm.
研究领域:
分析化学
·
环境科学
✓ 已验证
产品关联
DOI
MATERIALS SCIENCE FORUM
·
2019
·
IF 0
Yong Li Peng,Ni An Zhuo,Can Zhang
A new phosphorus-containing flame-retardant curing agent PPDTA was synthesized from phenylphosphonic dichloride (PPD) and 3-amino-1,2,4-triazole (TA) in tetrahydrofuran solvent to improve the flame retardancy of epoxy resin. The structure of the compound was analyzed and confirmed by infrared spectroscopy. The effects of reaction time, reaction temperature and ratio of reactants on yield were studied by using three-factor three-level orthogonal experiment. The results show that the yield of PPDTA can reach 86.4%, when the reaction time is 10h, reaction temperature is 70 °Cand the molar ratio of TA to PPD is 2.2:1.
研究领域:
材料化学
·
高分子化学
✓ 已验证
产品关联
DOI
危险品化学品经营许可证（带存储）