Preparation and Surface Modification of Fe3O4@Sio2 Composite Microspheres

2012 ◽  
Vol 455-456 ◽  
pp. 115-120
Author(s):  
Kui Zhou ◽  
Ming Yang ◽  
Qian Sun ◽  
Zhi Zuo Yang

Magnetic Fe3O4@SiO2 composite microspheres were prepared using hydrolyzation of tetraethoxysilane and Fe3O4 nanoparticles as seeds, and then the resultant composite particles were modified with silane coupling agent 3-methacryloxypropyltrimethoxy silane. The products were characterized by scanning electron microscope, X-ray powder diffraction, fourier transform infrared spectroscopy, and vibrating-sanple magnetometry, respectively. The results clearly show that the magnetic particles have favorable superparamagnetism and remain strong magnetic response. Moreover, the duplex bonds of carbon functional groups from 3-methacryloxypropyltrimethoxy silane was introduced onto the suface of Fe3O4@SiO2 composite particles.

2014 ◽  
Vol 881-883 ◽  
pp. 1424-1430 ◽  
Author(s):  
Nian Yi Wang ◽  
Zhi Qi Liu ◽  
Li Juan Li ◽  
Li Xia Zhu

The surface of magnesium hydroxide (MH) was modified with a silane coupling agent A-174 (3-methacryloxypropyltrimethoxysilane) to improve MH dispersion and hydrophobicity. The effects of modification on the resultant product and the mechanisms involved were studied through activation index analysis, thermogravimetric analysis, Fourier transform infrared spectroscopy and scanning electron microscope. The optimum modification conditions were obtained as follows: an A-174 dosage of 1.5 wt.% at 145 °C for 10 min at a stirring rate of 3000 rpm. A chemical reaction was observed between the MH surfaces and A-174. The dispersion and hydrophobicity of MH remarkably improved after surface modification.


2012 ◽  
Vol 554-556 ◽  
pp. 494-497
Author(s):  
Kai Du ◽  
Rong Hui Wei ◽  
Ya Nan Bai ◽  
Yadi Gu ◽  
Li Ben Li

Synthesis and characterization of microsheets, microrods, microflowers and microspheres of orthorhombic phase molybdenum oxide (MoO3) were reported. The reaction between ammonium molybdate and hydrochloric acid was used to prepare MoO3microstructures and followed by annealing in air at 400oCfor 2h. The combined techniques of X-ray powder diffraction (XRD), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and Raman spectroscopy were used to investigate the effect of pH and additives on the as-prepared samples. Results indicated that they were of microsize. With alcohol as an additive, the sample was plate-like MoO3at pH=2.5, and it was a mixture of MoO3and MoO3•0.55H2O of irradiative corolla at pH=1. The sample obtained by hydrothermal was MoO3flowers. Meanwhile, when silane coupling agent was introduced as the additive, the sample was MoO3spheres.


2008 ◽  
Vol 375-376 ◽  
pp. 87-91
Author(s):  
Yong Wei Zhu ◽  
Xiang Yang Xu ◽  
Bai Chun Wang ◽  
Jian Liang Shen

Mechano-chemical modification (MCM) of nanodiamond was conducted with a stirring mill. A new type of silane coupling agent, GW was chosen as its modifier. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared (FT-IR) were employed to study the surface properties of nanodiamond before and after treatments. Results showed that the peaks related to GW and the ball (for example, Fe, Si and Cl) appeared obviously after its MCM on their XPS spectra and mostly disappeared after its further purification with acid X or Y. A new peak located at 1382.48cm-1 was very strong after further purification. It was proven by their FT-IR spectra.


Arena Tekstil ◽  
2013 ◽  
Vol 28 (1) ◽  
Author(s):  
Maya Komalasari ◽  
Bambang Sunendar

Partikel nano TiO2 berbasis air dengan pH basa telah berhasil disintesis dengan menggunakan metode sol-gel dan diimobilisasi pada kain kapas dengan menggunakan kitosan sebagai zat pengikat silang. Sintesis dilakukan  dengan prekursor TiCl4 pada konsentrasi 0,3 M, 0,5 M dan 1 M, dan menggunakan templat kanji dengan proses kalsinasi pada suhu 500˚C selama 2 jam. Partikel nano TiO2 diaplikasikan ke kain kapas dengan metoda pad-dry-cure dan menggunakan kitosan sebagai crosslinking agent. Berdasarkan hasil Scanning Electron Microscope (SEM),diketahui bahwa morfologi partikel TiO2 berbentuk spherical dengan ukuran nano (kurang dari 100 nm). Karakterisasi X-Ray Diffraction (XRD) menunjukkan adanya tiga tipe struktur kristal utama, yaitu (100), (101) dan (102) dengan fasa kristal yang terbentuk adalah anatase dan rutile. Pada karakterisasi menggunakan SEM terhadap serbuk dari TiO2 yang telah diaplikasikan ke permukaan kain kapas, terlihat adanya imobilisasi partikel nano TiO2 melalui ikatan hidrogen silang dengan kitosan pada kain kapas. Hasil analisa tersebut kemudian dikonfirmasi dengan FTIR (Fourier Transform Infra Red) yang hasilnya memperlihatkan puncak serapan pada bilangan gelombang 3495 cm-1, 2546 cm-1, dan 511 cm-1,  yang masing-masing diasumsikan sebagai adanya vibrasi gugus fungsi O-H, N-H dan Ti-O-Ti. Hasil SEM menunjukkan pula bahwa kristal nano yang terbentuk diantaranya adalah fasa rutile , yang berdasarkan literatur terbukti dapatberfungsi sebagai anti UV.


2016 ◽  
Vol 5 (1) ◽  
pp. 6
Author(s):  
Budi Setiawan ◽  
Erizal Zaini ◽  
Salman Umar

Sebuah penelitian tentang sistem dispersi padat dari asiklovir dengan poloxamer 188 telah dilakukan formulasi dengan pencampuran secara fisika dengan rasio 1 : 1, 1 : 3, 1 : 5 dan dispersi padat 1 : 1, 1 : 3, 1 : 5 dan penggilingan 1:1 sebagai pembanding. Dispersi padat dibuat menggunakan metode pencairan (fusi), yang digabung dengan poloxamer 188 pada hotplate kemudian asiklovir dimasukkan ke dalam hasil poloxamer 188 lalu di kocok hingga membentuk masa homogen. Semua formula yang terbentuk termasuk asiklovir poloxamer 188 murni dianalisis karakterisasinya dengan Differential Thermal Analysis (DTA), X-ray Diffraction, Scanning Electron Microscopy (SEM), dan Fourier Transform Infrared (FTIR), kemudian pengambilan dilakukan  (penentuan kadar) mengunakan spektrofotometer UV pada panjang gelombang 257,08 nm dan uji laju disolusi dengan aquadest bebas CO2 menggunakan metode dayung. Hasil pengambilan  (penentuan kadar) menunjukkan bahwa semua formula memenuhi persyaratan farmakope Amerika edisi 30 dan farmakope Indonesia edisi 4 yaitu 95-110%. Sedangkan hasil uji laju disolusi untuk campuran fisik 1: 1, dan dispersi padat 1: 1, dan penggilingan 1: 1 menunjukkan peningkatan yang nyata dibandingkan asiklovir murni. Hal ini juga dapat dilihat dari hasil perhitungan statistik  menggunakan analisis varian satu arah  SPSS 17.


2009 ◽  
Vol 79-82 ◽  
pp. 505-508
Author(s):  
Li Li ◽  
H. Zhao ◽  
Wei Wang ◽  
F.F. Nie

The magnetic Fe3O4 nanoparticles had been synthesized by co-precipitation process and surface treatment by silane coupling agent (KH570). The magnetic Fe3O4/PMMA nanocomposite films were prepared by blend method, and the chemical structure, mechanical properties, surface morphology and the biocompatibility of the nanocomposite films were studied in this work. The magnetic Fe3O4 nanoparticles were well dispersed in the Fe3O4/PMMA nanocomposite films. The strength of the nanocomposite films, as well as the strain, decreased first and then increased with the increasing of the nanoparticles. The hemolytic ratio indicated that the nanocomposite films had a better blood compatibility.


2012 ◽  
Vol 476-478 ◽  
pp. 2059-2062
Author(s):  
Chen Wang ◽  
Ya Dong Li ◽  
Gu Qiao Ding

Tributyl borate was first adopted for the introduction of boron in the preparation of bioactive borosilicate xerogel by sol-gel method. The xerogel reacted continuously in 0.25M K2HPO4 solution with a starting pH value of 7.0 at 37 °C for 1day. The structural, morphologies and compositional changes resulting from the conversion were characterized using X-ray diffraction, scanning electron microscopy and Fourier transform infrared spectroscopy. The results indicated that speed of formation of HA was cut way back on the time with the addition of boron and the induction period for the HA nucleation on the surface of the borosilicate xerogel was short than 1 days. The conversion mechanism of the borosilicate xerogels to hydroxyapaptite was also discussed.


2020 ◽  
Vol 70 (1) ◽  
Author(s):  
Xiujie Gong ◽  
Hongtao Zou ◽  
Chunrong Qian ◽  
Yang Yu ◽  
Yubo Hao ◽  
...  

Abstract Purpose The highly efficient degradation bacteria were selected from the humus from the very cold straw in China for many years to construct the in situ degradation bacteria, and the degradation efficiency of corn straw was determined by process optimization. Methods According to the main components of corn straw, through morphological, physiological, and biochemical screening, three highly efficient complementary degradation strains were selected to construct the compound flora, and the degradation efficiency was analyzed by Fourier transform infrared spectrometer, field emission scanning electron microscope, and X-ray diffractometer. Result The corn straw selected in this paper is mainly composed of cellulose (31.99%), hemicellulose (25.33%), and lignin (14.67%). Through the determination of enzyme activity, strain Streptomyces sp. G1T has high decomposition ability to cellulose and hemicellulose but weak utilization ability to lignin; strain Streptomyces sp. G2T has the strongest decomposition ability to cellulose and hemicellulose among the three strains. The decomposition ability of strain Streptomyces sp. G3T to lignin was the strongest among the three strains. Therefore, by compounding the three strains, the decomposition ability has been greatly improved. The optimal process conditions obtained by single factor and response surface method are as follows: pH is 7, temperature is 30 °C, inoculation amount is 5%, rotational speed is 210 rpm, and the weight loss rate of straw is 60.55% after decomposing for 7 days. A large amount of degradation of corn straw can be seen by Fourier transform infrared spectrometer, field emission scanning electron microscope, and X-ray diffractometer. Conclusion Streptomyces sp. G1T, Streptomyces sp. G2T, and Streptomyces sp. G3T screened from straw humus in very cold areas were used to construct in situ degradation bacteria, which had good straw degradation activity and had the potential to be used for straw treatment in cold areas after harvest. This characteristic makes the complex bacteria become a strong competitive candidate for industrial production, and it is also an effective biotechnology in line with the current recycling of resources.


2016 ◽  
Vol 20 (3) ◽  
pp. 967-972 ◽  
Author(s):  
Peng Liu ◽  
Chun-Hui He ◽  
Fujuan Liu ◽  
Lan Xu ◽  
Yuqin Wan ◽  
...  

In this work, ?-Fe2O3 nanobulk with high aspect ratio were successfully prepared via a facile bubble electrospinning technique using polyvinylidene fluoride and iron chloride hexahydrate (FeCl3?6H2O) as ?-Fe2O3 precursor followed by annealing in air at 600?C. The products were characterized with field emission scanning electron microscope, Fourier transform infrared, X-ray photoelectron spectroscopy, and thermogravimetric analysis. The results showed that ?-Fe2O3 nanobulk has a hierarchical heterostructure which has an extremely broad application prospect in many areas.


Sign in / Sign up

Export Citation Format

Share Document