scholarly journals SYNTHESIS AND CHARACTERIZATION OF CROSSLINKED POLYACRYLAMIDE (PAAM)-CARRAGEENAN HYDROGELS SUPERBASORBENT PREPARED BY GAMMA RADIATION

2010 ◽  
Vol 10 (1) ◽  
pp. 12-19 ◽  
Author(s):  
Erizal Erizal
Keyword(s):  
Aqueous Solution ◽  
Gamma Rays ◽  
Room Temperature ◽  
Synthesis And Characterization ◽  
Optimum Conditions ◽  
Medium Ph ◽  
Gel Fraction ◽  
Ft Ir ◽  
Poly Acrylamide

A series of superabsorbent hydrogels were prepared from acrylamide and carrageenan by gamma irradiation at room temperature. Carrageenan solutions with different concentration (0.5%, 1%, 1.5%, 2%) have been blended with 5% of acrylamide and irradiated at doses 20-40 kGy. The properties of the prepared hydrogel were evaluated in terms of the gel fraction and the kinetics swelling was studied. It was found that the incorporation only 2% carrageenan (kappa) with 5% acrylamide can produces an elastic hydrogel when irradiated with gamma rays up to 40 kGy. Under optimum conditions, poly(acrylamide)-carrageenan hydrogels with gel fraction ~ 60% and optimum swelling 250 g/g were prepared gamma radiolyticcally from aqueous solution containing 5% acrylamide and 2% carrageenan at the doses 20-40 kGy. The FT-IR spectra indicated that network of irradiated PAAM-carrageenan hydrogel was in the semi IPN structure. The hydrogels were also found to be sensitive to ionic strength of the medium, pH and temperature.   Keywords: carrageenan, acrylamide, irradiation, superbasorbent, crosslinking

scholarly journals Synthesis and characterization of yttrium aluminium garnet (YAG) powders

2007 ◽  
Vol 1 (1-2) ◽  
pp. 69-74 ◽  
Author(s):  
Magdalena Zarzecka-Napierala ◽  
Krzystof Haberko
Keyword(s):  
Aqueous Solution ◽  
Phase Composition ◽  
Citric Acid ◽  
Ethylene Glycol ◽  
Synthesis And Characterization ◽  
Yttrium Aluminium Garnet ◽  
Yttrium Aluminium ◽  
Ft Ir ◽  
Complexing Properties

In this paper synthesis and characterization of YAG powders, prepared by a process based on complexing properties of citric acid, was reported. Influence of citric acid estrification induced by 2-propanol or ethylene glycol on the system homogeneity was investigated. These reagents were introduced to aqueous solution of yttrium and aluminium nitrates. A variety of powders from Al2O3-Y2O3 system with different phase composition were obtained by altering the citrate to nitrate ratio. Evolution of the powders phase composition vs. temperature was investigated using DTA/TG, XRD, and FT-IR methods. The most interesting results were observed in case of the citric acid - propanol - relative nitrates system. The mole ratio of these reagents equal to 1: 2.5: 2.5 (nitrates (Al,Y): citric acid: 2-propanol) allowed to synthesize pure YAG phase powders at temperature as low as 950?C.

Synthesis and Characterization of SrSO4:Sm3+ Phosphor with Hierarchical Structures

2013 ◽  
Vol 683 ◽  
pp. 203-206 ◽  
Author(s):  
Jia Yue Sun ◽  
Guang Chao Sun ◽  
Dian Peng Cui ◽  
Bing Xue ◽  
Hai Yan Du
Keyword(s):  
Aqueous Solution ◽  
Phase Structure ◽  
Room Temperature ◽  
Hierarchical Structures ◽  
Luminescence Properties ◽  
Hierarchical Architecture ◽  
Synthesis And Characterization ◽  
Ambient Conditions ◽  
Uniform Diameter

The SrSO4 spherical aggregates with hierarchical architecture was fabricated by using Sr(NO3)2 react with Na2SO4 aqueous solution under ambient conditions at room temperature. The SrSO4 spherical aggregates have a uniform diameter of about 10μm, which are composed of numerous well-aligned single tablet-like SrSO4 crystalline oriented radially to their centre. The phase structure, microstructure and luminescence properties were characterized by XRD, SEM, PL and DRS, respectively.

SYNTHESIS AND CHARACTERIZATION OF A RODLIKE LIQUID CRYSTALLINE POLYURETHANE OLIGOMER

2010 ◽  
Vol 03 (03) ◽  
pp. 169-172
Author(s):  
CHUN WEI ◽  
QIU-SHAN GAO ◽  
YONG-YANG GONG ◽  
XUE-MEI XIONG ◽  
XIN SHEN
Keyword(s):  
Weight Loss ◽  
Liquid Crystalline ◽  
Room Temperature ◽  
Decomposition Temperature ◽  
Synthesis And Characterization ◽  
Smectic A ◽  
Smectic A Phase ◽  
Ft Ir ◽  
Dimethylformamide Solution

A novel rodlike liquid crystalline polyurethane (LCPU) oligomer was synthesized by polyaddition of hexane-1,6-diylbis(4-hydroxybenzoate) with toluene 2,4-diissocyanate in N, N′-dimethylformamide solution. The properties of the LCPU oligomer were investigated by FT-IR, DSC, TGA, POM, WAXD and SEM. The LCPU oligomer was a yellow powder at room temperature, which maintained a stable rodlike microstructure below its melting point, and had high crystallinity. The LCPU oligomer exhibited thermotropic liquid crystalline properties between 166–183°C, and the smectic-A phase with focal conic fan textures at the liquid crystal state was observed by POM. The decomposition temperature of the LCPU oligomer at 5% weight loss was 282°C.

scholarly journals Synthesis and Characterization of Fluorescent Polyoxometalate Nano-/Microrods

2010 ◽  
Vol 65 (5) ◽  
pp. 603-606 ◽  
Author(s):  
Yan Shen ◽  
Jun Peng ◽  
Changyun Chen ◽  
Dan Chen ◽  
Huanqiu Zhang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Elemental Analysis ◽  
Synthesis Method ◽  
Synthesis And Characterization ◽  
Average Ratio ◽  
Intense Fluorescence ◽  
Ft Ir

Fluorescent nano-/microrods of the polyoxometalate (POM) K4H[Eu(α-SiW11O39)- (H2O)2] ・ 17H2O were obtained in aqueous solution by a conventional synthesis method. The nano-/microrods have been characterized by elemental analysis and FT-IR, UV/Vis, and TG-DTA data, and their morphology was examined by ESEM-FEG, showing that the average ratio of diameter to length is 1 : 20. The obtained nano-/microrods exhibit a regular profile and an intense fluorescence.

Hydrothermal Synthesis and Characterization of Ca-Mg-Al Hydrotacite-Like Compounds

2011 ◽  
Vol 287-290 ◽  
pp. 569-572 ◽  
Author(s):  
Mao Lin Zhang ◽  
Yuan Gao ◽  
Long Feng Li
Keyword(s):  
Reaction Time ◽  
Ph Value ◽  
Raw Materials ◽  
Treatment Temperature ◽  
Molar Ratio ◽  
Synthesis And Characterization ◽  
Medium Ph ◽  
X Ray ◽  
Ft Ir

Ca-Mg-Al hydrotalcite-like compounds (CaMgAl-HTLcs) were synthesized by a hydrothermal method, and characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and differential thermal analysis (DTA) techniques. The effects of the medium pH value, the molar ratio of the raw materials, the reaction temperature and the reaction time on the structure of CaMgAl-HTLcs were studied. The results showed that increasing treatment temperature and reaction time could improve the crystallinity and monodispersity of hydrotalcite-like compound particles. And well-defined CaMgAl-HTLcs could be prepared at a pH value of 10~11 with n (Mg+Ca): n (Al) = 1~3 and n (Mg): n (Ca) = 1~3.

The Synthesis and Characterization of Zinc Borate Zn2B6O11·7H2O

2013 ◽  
Vol 652-654 ◽  
pp. 795-798
Author(s):  
Xin Liu ◽  
Shao Ju Bian ◽  
Dan Dan Gao ◽  
Qing Fen Meng ◽  
Ming Wei ◽  
...  
Keyword(s):  
Room Temperature ◽  
Raw Materials ◽  
Zinc Borate ◽  
Synthesis And Characterization ◽  
Ft Ir

Zinc borate Zn2B6O11•7H2O was prepared at room temperature using Na2B4O7•10H2O, ZnSO4•7H2O and H3BO3 as raw materials. The synthesized product was characterized by XRD, SEM, TG-DSC and FT-IR. SEM results showed that the synthesized zinc borate had uniform morphology with a length up to a few microns. The experiment result indicates that additional H3BO3 in starting materials was beneficial to the uniform morphology of Zn2B6O11•7H2O.

Synthesis and Characterization of Hydrophobic Modification Guar Gum

2014 ◽  
Vol 952 ◽  
pp. 121-124 ◽  
Author(s):  
Feng Chen ◽  
Xu Guang Wang ◽  
Ren Shu Yang
Keyword(s):  
Aqueous Solution ◽  
Ir Spectra ◽  
Apparent Viscosity ◽  
Guar Gum ◽  
Synthesis And Characterization ◽  
Hydrophobic Modification ◽  
Ft Ir ◽  
Long Chain

The HMG GG-C14 was prepared by pre-swelling guar gum hydrophobic modification in alcohol-aqueous solution, the optical reactive condition was determined by studying the respective influence of each condition on the performance of the resultant product, and the final product possessed an apparent viscosity of 19957mPa·s (the apparent viscosity of parent guar gum is 11764mPa·s) and a substituting degree of 0.93%. The Ft-IR spectra of GG and GG-C14 indicate the hydrophobic long chain alkyl was successfully grafted onto guar gum.

scholarly journals Synthesis and characterization of a new ZIF-67@MgAl2O4 nanocomposite and its adsorption behaviour

RSC Advances ◽  
2021 ◽  
Vol 11 (22) ◽  
pp. 13245-13255
Author(s):  
Mehdi Davoodi ◽  
Fatemeh Davar ◽  
Mohammad R. Rezayat ◽  
Mohammad T. Jafari ◽  
Mehdi Bazarganipour ◽  
...  
Keyword(s):  
Room Temperature ◽  
Magnesium Aluminate ◽  
Synthesis And Characterization ◽  
Magnesium Aluminate Spinel ◽  
Adsorption Behaviour ◽  
Zeolitic Imidazolate Framework ◽  
Simple Method

New nanocomposite of zeolitic imidazolate framework-67@magnesium aluminate spinel (ZIF-67@MgAl2O4) has been fabricated by a simple method at room temperature with different weight ratios.

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