Ionic bond in hydrogen transferring of the ferrous and/or ferric human/mouse verdoheme oxygenase

This research is aims to describe the validity of interactive multimedia based on Android in the ion bonding sub material. This research uses Thiagarajan's 4-D development research consisting of Define; Design; Development and Disseminate. However, this research is limited to the Development stage of Thiagarajan in Ibrahim (2014). Multimedia validity is reviewed from the aspect of content validity and construct validity. This multimedia was validated by 2 Unesa chemistry lecturers and 1 chemistry teacher with the research instrument used in the form of a multimedia validation sheet then the results of the validation resulted in a validation score. Based on data analysis, it can be concluded that android-based interactive multimedia on the ion bond sub-material is valid for use with percentage content validation and construct validity respectively 91.85% and 89.61% with highly valid criteria.

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Calcium carbonate modified urea–formaldehyde resin adhesive for strength enhanced medium density fiberboard production

RSC Advances ◽

10.1039/d1ra04316a ◽

2021 ◽

Vol 11 (40) ◽

pp. 25010-25017

Author(s):

Li Lu ◽

Yan Wang ◽

Tianhua Li ◽

Supeng Wang ◽

Shoulu Yang ◽

...

Keyword(s):

Calcium Carbonate ◽

Urea Formaldehyde ◽

Medium Density Fiberboard ◽

Urea Formaldehyde Resin ◽

Formaldehyde Resin ◽

Medium Density ◽

Ionic Bond ◽

Resin Adhesive ◽

Uf Resin ◽

Modified Urea

Reactions between CaCO3 and CH2O2 during polycondensation of UF resin produce Ca2+. Ionic bond complexation binds Ca2+ with UF resin. The UF resin crystalline percentage decreases from 26.86% to 22.71%. IB strength of resin bonded fiberboard increases from 0.75 to 0.94 MPa.

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Viscosity of Gelatin Solution Containing Cationic Crosslinker

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.750-752.1660 ◽

2013 ◽

Vol 750-752 ◽

pp. 1660-1663

Author(s):

Xiang Jian Meng ◽

Yue Zhi Cui ◽

Cong De Qiao ◽

Tian Duo Li ◽

Jing Xu

Keyword(s):

Thermal Stability ◽

Organic Compounds ◽

Quaternary Ammonium ◽

Quaternary Ammonium Salts ◽

Ammonium Salts ◽

Gelatin Solution ◽

Ionic Bond ◽

Organic Salts ◽

Thermal Stability Of

Gelatin, as an amphoteric polyelectrolyte, can combine with cationic or anionic organic compounds by ionic bond. In this work, two binary quaternary ammonium salts have been prepared from 1,2-ethanediamine and 1,4-butanediamine. The viscosity of aqueous gelatin solution containing these two organic salts is studied systematically, which verifies the occurrence of the crosslinking between the gelatin and the binary quaternary ammonium salts. This crosslinking improves the thermal stability of the dried gelatin.

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Salt bridges in model peptides

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19882810 ◽

1988 ◽

Vol 53 (11) ◽

pp. 2810-2824 ◽

Cited By ~ 2

Author(s):

Ilmars Sekacis ◽

Mark Shenderovich ◽

Gregory Nikiforovich ◽

Edvards Liepinš ◽

Ludmila Polevaya ◽

...

Keyword(s):

Synthetic Peptides ◽

Salt Bridge ◽

Peptide Bond ◽

Space Structure ◽

Side Chain ◽

Amino Group ◽

Salt Bridges ◽

Ionic Bond ◽

Theoretical Conformational Analysis ◽

H Nmr

A group of synthetic peptides including Boc-Lys-Phe-X-Y, X = Ala (I, III) or Thr (II), Y = Pro (I, II) or Ala (III) was studied by means of 1H NMR spectroscopy and theoretical conformational analysis. Compound I in DMSO shows two conformers with the trans- and cis-configuration of the peptide bond Ala-Pro. The salt bridge between the Lys ε-amino group and the C-terminal carboxyl is featured by magnetic nonequivalence of the Lys CεH2 protons. The space structure of I and II was found to possess a salt bridge fixed by an unusual turn in the chain formed by the Lys side chain and the C-terminal dipeptide with the trans-peptide bond X-Pro. Since a stable ionic bond in III and in the cis-conformer of I has not been observed, its contribution to stabilization of the space structure of the peptides in DMSO appears rather small.

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Antioxidant Effects of Green Tea Leaf Extract on Chemical properties of Corn Refined Oil of Microwave Fried Potatoes

International journal of basic science in medicine ◽

10.15171/ijbsm.2019.18 ◽

2019 ◽

Vol 4 (3) ◽

pp. 96-101

Author(s):

Masomeh Hoseini ◽

Maryam Fahim Danesh

Keyword(s):

Green Tea ◽

Leaf Extract ◽

Polar Compounds ◽

Butylated Hydroxytoluene ◽

Heating Process ◽

Ionic Bond ◽

Refined Oil ◽

Peroxide Content ◽

Tea Leaf ◽

Fried Potatoes

Introduction: Oxygen, light, heat, metal ions, and enzymes are among the agents that oxidize oils, fats, and high-fat food products which result in oxidative spoilage. Due to the toxicity and cancer risk of oxidative agents, the use of synthetic antioxidants is important for delaying the oxidation processes. The purpose of this study was to evaluate the protective effect of natural antioxidants including green tea leaf extract and butylated hydroxytoluene (BHT) on the oxidation of the corn refined oil of microwave-heated fried potatoes. Methods: To this end, corn refined oil and corn oil were treated with green tea leaf extracts (i.e., 200, 400, 600, and 800 ppm), followed by treating the oils with a combination of green tea leaf extract (600 ppm) and BHT (200 ppm). The samples with no anti-oxidant treatments were used as the controls. Eventually, several parameters related to the corn oils were determined, including peroxide content, acidity, polar compounds, and ionic bond conjugates. Results: Based on the results, significant increases were observed in peroxide, acidity, polar compounds, and ionic bond conjugates in the corn refined oil of microwave fried potatoes (P<0.05). On the other hand, the results showed that the heating process reduced peroxide content (P<0.05). However, acidity increased significantly during the heating process (P>0.05) and the lowest acid value was observed in the mixture of 600 ppm of the green tea leaf with 200 ppm of the BHT. There was no significant difference between the control group and the samples treated with 200 ppm of the green leaf extract (P<0.05) in terms of polar components. In addition, a significant decrease was found in the conjugated dienes by increasing the green tea leaf extract concentration (P<0.05). Finally, the highest protection was achieved in the oils that were treated with a combination of green tea leaf extract and BHT. Conclusion: In general, the green tea leaf extract and BHT have antioxidant activities that make them suitable agents for use in food protection industries.

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Scorch Control of Carboxylic Elastomers

Rubber Chemistry and Technology ◽

10.5254/1.3545024 ◽

1973 ◽

Vol 46 (1) ◽

pp. 78-95 ◽

Cited By ~ 4

Author(s):

V. L. Hallenbeck

Keyword(s):

Zinc Oxide ◽

Physical Properties ◽

Shelf Life ◽

Zinc Sulfide ◽

Zinc Phosphate ◽

Carboxyl Groups ◽

Carboxyl Group ◽

Phosphate Coating ◽

Ionic Bond ◽

Cure Temperature

Abstract Carboxylic elastomers can be cured by standard compounding recipes utilizing sulfur and zinc oxide. The zinc oxide, besides aiding the sulfur cure, also gives a secondary cure through an ionic bond with the carboxyl groups. However, because of the affinity of the zinc oxide for the carboxyl group, the stocks tend to have an excessive scorch and a short shelf life. To prevent this excessive scorch the zinc oxide must be isolated from the carboxyl group until the desired cure temperature is reached. Three materials may be used to isolate the zinc oxide : 1) zinc sulfide coated zinc oxide, 2) zinc phosphate coated zinc oxide and 3) metallic alkoxide combined with the zinc oxide. The use of any of these gives scorch control without affecting final physical properties. The amount of zinc sulfide coating, zinc phosphate coating, and metallic alkoxide varies with the type of carboxylic elastomer.

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