scholarly journals Characterization of tannin based colorimetric indicator and its application on fish packaging

2021 ◽  
Vol 922 (1) ◽  
pp. 012057
Author(s):  
N M Erfiza ◽  
N R Purba ◽  
K Ahda ◽  
I Sulaiman ◽  
S Rohaya ◽  
...  
Keyword(s):  
Ph Value ◽  
Storage Conditions ◽  
Aromatic Rings ◽  
Fish Fillet ◽  
Powder Concentration ◽  
Fish Fillets ◽  
Colorimetric Indicator ◽  
Ft Ir ◽  
Color Indicator

Abstract This study aims to determine characteristics of the gel-type colorimetric indicator at various pH and under different storage conditions, then determine the indicator characteristic in the packaging of fish fillets during storage. The gel-type color indicator was synthesized with a concentration of 1%, 3%, and 5% gambir powder. The FT-IR spectra of the color indicator showed the presence of tannin functional groups, namely C=C aromatic rings, C-C phenolic, and C-H groups, respectively at wavenumbers 1517-1519, 1440-1475, and 752-761 1/cm. Moreover, the coefficient value of the Red-Green-Blue (RGB) of the indicator was changed over pH and did not appear to be consistent. Based on the Analysis of Variance (ANOVA) test, the concentration of gambir powder and duration of color indicator storage, respectively, had a significant effect (P <0.05) on the value of the RGB coefficient. The color indicator exposed to sunlight had a smaller RGB coefficient value than the RGB coefficient value of the indicator stored at room temperature and 5-7°C. The application of color indicators with a 1% Gambir powder concentration in fish fillet storage has been tested for 5 days at a temperature of 5-7°C. They showed that the RGB coefficient value of the indicator was proportional to changes in the pH value of fish fillets but not in line with changes in Total Volatile Based Nitrogen (TVBN) of fish fillets.

Microwave-assisted solvent-free synthesis and spectral and structural characterization of cyclotriphosphazene hexakis(o-tolylamide)

2018 ◽  
Vol 73 (12) ◽  
pp. 999-1003 ◽  
Author(s):  
Mohammad Hakimi ◽  
Homeyra Rezaei ◽  
Keyvan Moeini ◽  
Heidar Raissi ◽  
Vaclav Eigner ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
Microwave Irradiation ◽  
Stacking Interactions ◽  
X Ray Diffraction ◽  
Aromatic Rings ◽  
X Ray ◽  
Microwave Assisted ◽  
Ft Ir ◽  
Solvent Free Synthesis

AbstractA new cyclotriphosphazene, 2,2,4,4,6,6-hexakis (o-tolylamono)-1,3,5,2λ5,4λ5,6λ5-triazatriphosphinine (MPAP), was prepared using microwave irradiation and identified by elemental analysis, FT-IR, Raman, 31P NMR spectroscopy, and single-crystal X-ray diffraction. In the crystal, in addition to hydrogen bonds, the network is further stabilized by inter- and intramolecular π–π stacking interactions between aromatic rings.

Synthesis and Characterization of Zn-Ca-Mg-Al Hydrotacite-Like Compounds and its Application in the PVC

2011 ◽  
Vol 66-68 ◽  
pp. 65-69
Author(s):  
Long Feng Li ◽  
Yuan Gao ◽  
Mao Lin Zhang
Keyword(s):  
Reaction Time ◽  
Ph Value ◽  
Raw Materials ◽  
Treatment Temperature ◽  
Molar Ratio ◽  
Medium Ph ◽  
X Ray ◽  
Ft Ir ◽  
Thermal Stability Of

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(Zn+Mg+Ca):n(Al) =2. The products synthesized were applied to PVC to improve the thermal stability of PVC.

Fractional Extraction and Structural Characterization of Coconut Shell Hemicellulose

2014 ◽  
Vol 716-717 ◽  
pp. 108-113 ◽  
Author(s):  
Feng Hui Zhao ◽  
Yong Chen ◽  
Run Liu Chen ◽  
Min Liu ◽  
Yu Qiang Guo ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Potassium Hydroxide ◽  
Ph Value ◽  
Potassium Hydroxide Solution ◽  
Gel Permeation Chromatography ◽  
Coconut Shell ◽  
Optimal Conditions ◽  
Alkaline Peroxide ◽  
Ft Ir

Three principal components (cellulose, lignin, and hemicellulose) of coconut shell (CS), an abundant tropical biomass, were quantified using the Van Soest method. It was observed that CS had a high content of hemicellulose (30% of the raw CS material). The present study was undertaken to investigate the extractability of hemicellulose from CS obtained by ultrasound-assisted potassium hydroxide solution with the hydrogen peroxide method. The ultrasonic treatment and sequential extractions with alkali and alkaline peroxide under optimal conditions led to a release of more than 93% of the original hemicellulose. The effects of experimental variables, including pH value, reaction temperature and time, hydrogen peroxide content, and magnesium sulfate dosage on hemicellulose content were investigated. The obtained hemicelluloses were characterized by Fourier transform infrared spectroscopy (FT-IR), gel permeation chromatography (GPC), and comprehensive thermal analysis (TGA), which showed that potassium hydroxide significantly affected the yield of relatively pure hemicellulose.

scholarly journals Removal of Cr(VI) From Water Resources by Using Different Raw Inorganic Sorbents

2017 ◽  
Vol 14 (3-4) ◽  
Author(s):  
Hamdije Memedi ◽  
Katerina Atkovska ◽  
Kiril Lisichkov ◽  
Mirko Marinkovski ◽  
Stefan Kuvendziev ◽  
...  
Keyword(s):  
Water Resources ◽  
Ph Value ◽  
Spectrophotometric Analysis ◽  
Point Of Zero Charge ◽  
Natural Minerals ◽  
Mineralogical Characteristics ◽  
Bet Method ◽  
Ft Ir ◽  
The Republic

Natural minerals from different localities in the Republic of Macedonia are selected for elimination of Cr(VI) ions from water resources. For that aim are selected: aksil (Kriva Palanka), trepel (Bitola), SiO2 amorphous (Kozuf), pemza (Bojanciste). In this study, their adsorption capacity is analyzed using spectrophotometric method (UV/VIS Spectrophotometer). Results from the spectrophotometric analysis in all used examples gave us insight for the starting concentration of Cr(VI) before adsorption and concentration after adsorption. The physical, chemical and mineralogical characteristics of adsorbents are studied. XRD, TGA-DTA and FT-IR analysis are used for characterization of natural mineral materials. The surface area of the sorbents were measured by BET method. With aim to determine the optimum pH value for maximal removal of Cr(VI) ions, the point of zero charge, pHPZC, for investigated materials were obtained. The aim of the study is to select which adsorbent is more efficient for elimination of Cr(VI) from water resources. According to obtained results all of them were successful in elimination of Cr(VI), but more efficient and economic is trepel.

Synthesis, Characterization of Bimetallic V-Fe-SBA-15 and Its Catalytic Performance in the Hydroxylation of Phenol

2007 ◽  
Vol 7 (12) ◽  
pp. 4508-4514 ◽  
Author(s):  
Fei Gao ◽  
Yanhua Zhang ◽  
Chunling Wang ◽  
Cheng Wu ◽  
Yan Kong ◽  
...  
Keyword(s):  
Ph Value ◽  
High Surface ◽  
Mesoporous Structure ◽  
Catalytic Performance ◽  
Hydroxylation Of Phenol ◽  
Surface Areas ◽  
Hexagonal Arrangement ◽  
Ft Ir ◽  
Catalytic Performances

A series of V-Fe incorporated-SBA-15 has been synthesized by adjustment of the pH value of the gel mixtures and characterized by using XRD, N2-adsorption, ICP, FT-IR, Raman, and UV–vis techniques. Results indicated that all samples exhibited typical hexagonal arrangement of mesoporous structure with high surface areas and the heteroatoms were probably incorporated into the framework of SBA-15. Catalytic performances of the obtained materials were evaluated in the hydroxylation of phenol with H2O2, and the catalytic results revealed that the selectivity for catechol (CAT) and hydroquinone (HQ) could be controlled by adjusting the contents of V and Fe in the samples, and an appropriate nV/nFe mol ratio in SBA-15 could approach the optimal catalytic performance.

scholarly journals Synthesis and Characterization of Industrial Casting Sand Based Silica Aerogel

2021 ◽  
Vol 9 (12) ◽  
pp. 1254-1258
Author(s):  
Tuba Arkan
Keyword(s):  
Silica Aerogel ◽  
Ph Value ◽  
Sol Gel ◽  
Sodium Silicate Solution ◽  
Silicate Solution ◽  
Chemical Components ◽  
Ft Ir ◽  
Casting Sand ◽  
Xrf Analyses

Abstract: In this study, a commercial foundry sand (Seydisehir Eti Aluminium Co. Inc.) was provided as the starting material. Using this supplied casting sand, silica aerogel production was carried out by sol-gel method. Starting materials chemical components were determined by doing XRD and XRF analyses to starting industrial casting sand respectively. After analysing studies, sodium silicate solution was produced from commercial casting sand. During silica aerogel synthesize, 5 different pH degree was investigated including 2-4-6-8 and 9. Silica aerogel modification (Super hydrophobic) was made by choosing the optimum pH value. Afer then, on the synthesized experiment sample, FT-IR, BET, SEM and contact angle characterization studies were realised respectively. As a result of preliminary experiments done with different pH experiments, sample with the lowest density was determined as pH 8 value. Keywords: Casting sand, Sol-gel, Silica aerogel

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.

scholarly journals Synthesis and characterization of polymethylsilsesqui oxane microspheres by the two-step sol-gel method

e-Polymers ◽  
2012 ◽  
Vol 12 (1) ◽  
Author(s):  
Jiangbo Wang ◽  
Zhong Xin
Keyword(s):  
Ph Value ◽  
Condensation Reaction ◽  
Sol Gel ◽  
Average Diameter ◽  
Reaction Conditions ◽  
Gel Method ◽  
Sol Gel Method ◽  
Ft Ir ◽  
Thermal Stability Of

AbstractPolymethylsilsesquioxane (PMSQ) microspheres with an average diameter of 30nm to 6μm were prepared from methyltrimethoxysilane (MTMS) by a two-step sol-gel method in the presence of hexadecyl trimethyl ammonium chloride (HTAC). The reaction conditions including the concentration of HTAC, water/MTMS ratio, pH value and the temperature in condensation reaction were examined, and aggregation of the microspheres was not observed during the preparation process. Moreover, the structure and thermal stability of PMSQ microspheres were investigated by FT-IR, XRD, TGA, and so on.

scholarly journals Geopolymer Composite Coatings Based on Moroccan Clay and Sands for Restoration Application

2021 ◽  
Vol 3 ◽  
Author(s):  
Anass El Khomsi ◽  
Ameni Gharzouni ◽  
Remi Farges ◽  
Patrice Duport ◽  
Nourredine Idrissi Kandri ◽  
...  
Keyword(s):  
Contact Angle ◽  
Adhesive Strength ◽  
Ph Value ◽  
Composite Coatings ◽  
Storage Conditions ◽  
Solid Ratio ◽  
Historical Monuments ◽  
Geopolymer Binder ◽  
High Adhesive Strength

This study aims to explore geopolymer binders and mortars based on local Moroccan clays and sands as coatings for the restoration of historical monuments in Morocco. For this, five substrates, one geopolymer binder, and two geopolymer mortars were investigated. The characterization of substrates reveals differences in terms of pH value, capillarity, contact angle, and surface roughness. These differences affect the coating thickness, which also depends on the viscosity, liquid to solid ratio, and granular skeleton of the geopolymer coating. High adhesive strength values (up to 9 MPa) were obtained on limestones. However, these values decreased with the increase of relative humidity. In the case of Fez stone, a stable adhesive strength value (3 MPa) was evidenced for all the coating formulations and at different storage conditions confirming the suitability of coating based on metakaolin, Moroccan clays, and sands for restoration applications.

scholarly journals Utilization of areca nut (Arecha chatechu L.) extract for tannin based colorimetric indicator in smart packaging

2022 ◽  
Vol 951 (1) ◽  
pp. 012057
Author(s):  
N R Yanti ◽  
M Andika ◽  
S Maulida ◽  
Riani ◽  
I Sulaiman ◽  
...  
Keyword(s):  
Room Temperature ◽  
Ethanolic Extract ◽  
Storage Conditions ◽  
Temperature Sensitive ◽  
Areca Nut ◽  
Smart Packaging ◽  
Food Industries ◽  
Colorimetric Indicator ◽  
Whatman Paper

Abstract Areca nut contains tannin which has a great potential to apply as natural colour agent in food industries. Tannin offers specific colour and alter its colour due to environmental sensitivity. This study aims to fabricate a tannin-based colour indicator from areca nut in smart packaging in the form of a strip type and to characterize the indicator at different storage conditions and at various pH solutions. The indicators were synthesized using filter paper (No.1 and No.42) soaked in a solution with 1, 3, and 5% areca nut ethanolic extract. Then the indicators were stored at room temperature and 4-7°C for 10 days, then their Red Green Blue (RGB) coefficient values were measured. Characterization of the indicators at pH 3-10 were also determined by RGB coefficient. The results showed that the indicator stored at 4-7°C had more stable RGB coefficient than the indicator stored at room temperature indicated the indicator was influenced by the temperature factor. The indicator offered a potential to be used as a sensor on packaging of temperature sensitive foods. The indicator using Whatman paper No.42 with 1% of extract steadily decreased in RGB coefficient and changed its colour to darker in basic pH solution while the indicator with other treatments had unstable alteration RGB coefficient and colour.

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