Synthesis and characterization of hydrogel bonded with rare earth

Chitosan-poly（acryfic acid） hydrogel bonded with Eu^3＋ was prepared by radical solution polymerization. Biodegradable chitosan, N,N＇-methylen-diacrylamide, and potassium persulphate were used as the basic material, cross-linking agent, and initiator, respectively. The structure and thermal property of hydrogel were characterized by infrared spectrometry, X-ray diffraction, scanning electron microscopy, and differential scanning calorimetry. The swollen property and fluorescent performance were also characterized. The results showed that the rare earth presented unique distribution in the hydrogel due to the formation of chemical bonds after polymerization. The glass transition temperature of the hydrogel decreased remarkably, which might broaden the range of its elastic application considerably. Moreover, the characteristic fluorescent emission of Eu^3＋ was observed in the hydrogel, which was indicative of the excellent luminescent performance.     

溶胶-凝胶法制备的BaMgAl10O17:Eu前驱体的晶化过程

采用柠檬酸作为螯合物的溶胶-凝胶法制备了BaMgAl10O17：Eu(barium magnesium aluminate,BAM)蓝色荧光粉,并研究了,其晶化过程。通过X射线衍射、扫描电镜和荧光光谱等表征手段,研究了前驱体晶化过程的焙烧条件、结晶动力学、颗粒大小和发光性能等。BAM晶相在1100℃开始产生。温度达1200℃时,前驱体由无定型态完全转变成BAM晶相。在1120～1300℃时晶化反应的表观活化能为233kJ／mol。在室温下测得荧光粉的最大吸收峰和发射峰分别处在334nm和454nm。合成荧光粉的粒径为5μm左右,其形态和粒径取决于前驱体。     

活性硅醇与ENR开环反应及对硫化胶力学性能的影响

以过氧羧酸为环氧化剂,制得环氧化天然橡胶(ENR)。通过从水玻璃中提取的活性硅醇与ENR的开环反应,得到含硅杂化材料ENR-SiO2,测试了其对NE硫化胶力学性能的影响,发现含硅杂化材料对NR硫化胶有明显的增强作用。     

PMMA-SiO2杂化材料对天然橡胶的增强作用

提取了活性硅烷醇,用自由基共聚合法成了含硅高聚物,分析了SiO2含量对硫化天然橡胶力学性能的影响。     

溶胶-凝胶法制备的BaMgAl_(10)O_(17)∶Eu前驱体的晶化过程(英文)

采用柠檬酸作为螯合物的溶胶-凝胶法制备了BaMgAl10O17∶Eu(bariummagnesiumaluminate,BAM)蓝色荧光粉,并研究了其晶 化过程。通过X 射线衍射、扫描电镜和荧光光谱等表征手段,研究了前驱体晶化过程的焙烧条件、结晶动力学、颗粒大小和发光性能等。BAM 晶相在1100℃开始产生。温度达1200℃时,前驱体由无定型态完全转变成BAM晶相。在1120～1300℃时晶化反应的表观活化能为 233kJ/mol。在室温下测得荧光粉的最大吸收峰和发射峰分别处在334nm和454nm。合成荧光粉的粒径为5μm左右,其形态和粒径取决于 前驱体。     

Synthesis of Long Afterglow Phosphors MAl_2O_4∶Eu~(2 ), Dy~ (3 )(M=Ca, Sr, Ba) by Microemulsion Method and Their Luminescent Properties

LongafterglowphosphorsMAl2O4∶Eu2 ,Dy3 (M=Ca,Sr,Ba)haveattractedmuchinterestsfrom1990sowingtotheirexcellentpropertiessuchaslight andheatendurance,chemicalstability,highlumines centintensity,longafterglowtime,containingno poi sonouselementandsoon[1～6].Tra…     

Synthesis of Long Afterglow Photoluminescent Materials Sr_2MgSi_2O_7∶Eu~(2 ), Dy~(3 ) by Sol-Gel Method

Withtheprogressofsocialcivilizationanddevel opmentofmodernscienceandtechnology ,thedemandforluminescentmaterialskeepsincreasingduetoitsgreatsocialandeconomicbenefits .Therefore ,prepa rationofluminescentmaterialswasregardedbypeopleveryearly .Asanembellish…     

Synthesis of Long Afterglow Photoluminescent Materials Sr2MgSi2O7：Eu^2＋,Dy^3＋ by Sol-Gel Method

Long afterglow photoluminescent materials Sr2MgSi2O7 dopeo With Eu^2 ,Dy^3 were prepared by sol-gel method. The synthesized samples were characterized by X-ray diffraction. The excitation spectrum, emission spectrum and long decay curve were measured and analyzed. XRD pattern indicates that phosphor is with Sr2MgSi2O7 crystal structure. The wide range of excitation wavelength indicates that luminescent material can be excited by light from ultraviolet ray to visible light. The main peak of emission spectrum is located at 466nm. Sample excited by visible light can emit bright blue light, and the afterglow time lasts more than 8h.     

Study on Preparation and Property of Poly－Aminosilicone－Rare Earth Composite

The poly-aminosilicone-rare earth composite was prepared by poly-aminosilicone cross-linked with rare earth and active silanol. The thermal stability of the composites was studied by thermogravimetric analysis (TG). Force condition of the composites in electric field was analyzed and relative polarizability was derived. It is found that the composites containing different rare earth ions have different relative polarizability. The experiment results reveal that organosilicon materials with different electrical performance can be obtained by this way. Meanwhile, the absorption and flourescene spectrum of composites were also investigated. Compared to rare earth chloride, the spectrum properties of the composite are changed obviously. The possible reasons for these phenomena were discussed.     

Study on Preparation and Properties of PVC Film Modified by Rare Earth

The transparent PVC films were prepared by tape casting. In the process of preparation, rare earth nitrate, as a kind of modifier, was added to the solution of PVC and THF. These PVC films were tested after being crosslinked by ultraviolet light. It is found that the mechanical and physical properties of all the PVC films modified by rare earth nitrate are greatly enhanced.