Preparation of Acylated Blueberry Anthocyanins through Enzymatic Method in Aqueous/Organic Phase: Effects on its Colour Stability and pH-Response Characteristics

2021 ◽  
Author(s):  
Fansen Zeng ◽  
HaiSheng Zeng ◽  
Yanqi Ye ◽  
Shiyu Zheng ◽  
Jingna Liu ◽  
...  
Keyword(s):  
Gallic Acid ◽  
Organic Phase ◽  
Colour Stability ◽  
Enzymatic Method ◽  
Intelligent Packaging ◽  
Response Characteristics ◽  
Ph Response ◽  
The Stability

To explore the potential of anthocyanins in pH-colour responsive intelligent packaging and improve the stability of the pigments, 3,4,5-trimethoxybenzoic acid and gallic acid were grafted onto blueberry anthocyanins via enzyme-catalysed...

Extraction of strontium and barium salts by the nitrobenzene solution of dicarbolide in the presence of glymes

1985 ◽  
Vol 50 (3) ◽  
pp. 581-599 ◽  
Author(s):  
Petr Vaňura ◽  
Emanuel Makrlík
Keyword(s):  
Stability Constants ◽  
Organic Phase ◽  
Equilibrium Constants ◽  
Minor Role ◽  
Nitrobenzene Solution ◽  
Ligand Structure ◽  
Stability Constants Of Complexes ◽  
Separation Factors ◽  
The Stability ◽  
A Minor

Extraction of microamounts of Sr2+ and Ba2+ (henceforth M2+) from the aqueous solutions of perchloric acid (0.0125-1.02 mol/l) by means of the nitrobenzene solutions of dicarbolide (0.004-0.05 mol/l of H+{Co(C2B9H11)2}-) was studied in the presence of monoglyme (only Ba2+), diglyme, triglyme, and tetraglyme (CH3O-(CH2-CH2O)nCH3, where n = 1, 2, 3, 4). The distribution of glyme betweeen the aqueous and organic phases, the extraction of the protonized glyme molecule HL+ together with the extraction of M2+ ion and of the glyme complex with the M2+ ion, i.e., ML2+ (where L is the molecule of glyme), were found to be the dominating reactions in the systems under study. In the systems with tri- and tetraglymes the extraction of H+ and M2+ ions solvated with two glyme molecules, i.e., the formation of HL2+ and ML22+ species, can probably play a minor role. The values of the respective equilibrium constants, of the stability constants of complexes formed in the organic phase, and the theoretical separation factors αBa/Sr were determined. The effect of the ligand structure on the values of extraction and stability constants in the organic phase is discussed.

scholarly journals Antioxidant Network Based on Sulfonated Polyhydroxyalkanoate and Tannic Acid Derivative

2021 ◽  
Vol 8 (1) ◽  
pp. 9
Author(s):  
Laura Brelle ◽  
Estelle Renard ◽  
Valerie Langlois
Keyword(s):  
Gallic Acid ◽  
Tannic Acid ◽  
Water Soluble ◽  
Gel Formation ◽  
Ene Reaction ◽  
Inorganic Cations ◽  
Medium Chain Length ◽  
Physically Crosslinked ◽  
The Stability ◽  
Derivatives Of

A novel generation of gels based on medium chain length poly(3-hydroxyalkanoate)s, mcl-PHAs, were developed by using ionic interactions. First, water soluble mcl-PHAs containing sulfonate groups were obtained by thiol-ene reaction in the presence of sodium-3-mercapto-1-ethanesulfonate. Anionic PHAs were physically crosslinked by divalent inorganic cations Ca2+, Ba2+, Mg2+ or by ammonium derivatives of gallic acid GA-N(CH3)3+ or tannic acid TA-N(CH3)3+. The ammonium derivatives were designed through the chemical modification of gallic acid GA or tannic acid TA with glycidyl trimethyl ammonium chloride (GTMA). The results clearly demonstrated that the formation of the networks depends on the nature of the cations. A low viscoelastic network having an elastic around 40 Pa is formed in the presence of Ca2+. Although the gel formation is not possible in the presence of GA-N(CH3)3+, the mechanical properties increased in the presence of TA-N(CH3)3+ with an elastic modulus G’ around 4200 Pa. The PHOSO3−/TA-N(CH3)3+ gels having antioxidant activity, due to the presence of tannic acid, remained stable for at least 5 months. Thus, the stability of these novel networks based on PHA encourage their use in the development of active biomaterials.

scholarly journals Rust Conversion Performance of Phosphoric Acid-Gallic Acid in Vinyl Chloride Acrylic Emulsion

Coatings ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 152
Author(s):  
Xin Wang ◽  
Qingjun Zhu ◽  
Xiangju Liu ◽  
Baorong Hou
Keyword(s):  
Phosphoric Acid ◽  
Gallic Acid ◽  
Vinyl Chloride ◽  
Salt Spray ◽  
Corrosion Current ◽  
Oxidation Reactions ◽  
Acrylic Emulsion ◽  
Conversion Performance ◽  
The Stability ◽  
Iron Complexation

This work studied the application of phosphoric acid-gallic acid in vinyl chloride acrylic emulsion and its rust conversion performance. The increase of phosphoric acid affected the stability of the system, leading to the rapid precipitation of flocculent precipitation. Rust conversion coating (RCC) showed the best synergistic conversion effect when gallic acid (GA) was 0.2 wt.% and phosphoric acid (PA) was 2 wt.%. XRD and FTIR analysis show that the components of adherent rust (AR) are α-FeOOH, γ-FeOOH and Fe3O4. The conversion products are ferric phosphate (FP) and ferric gallate (FG). The RCC can effectively treat the rusted steel (RS) produced by simulated marine atmospheric corrosion. The corrosion current density was reduced by three orders of magnitude, the adhesion reached 2.75 MPa, and the salt spray corrosion resistance was 20 days. The results of Raman, XPS, SEM and EDS show that the ionic dissolution of iron, complexation and further oxidation reactions occur at the interface between the adherent rust and the RCC. After rust conversion treatment, unreacted rust (UR) affects the further improvement of adhesion strength and anti-corrosion performance.

Novel Fiber-Optic Sensing System for Detection of Methane

2013 ◽  
Vol 562-565 ◽  
pp. 1008-1015 ◽  
Author(s):  
Shu Tao Wang ◽  
Peng Wei Zhang ◽  
Quan Min Zhu
Keyword(s):  
Fiber Optic ◽  
Detection System ◽  
Step Motor ◽  
Harmonic Detection ◽  
Distributed Feedback Laser ◽  
Gas Cell ◽  
Response Characteristics ◽  
The Stability ◽  
Application Fields ◽  
Methane Detection

Based on DFBLD (Distributed Feedback Laser Diode) and harmonic detection technique, a novel fiber-optic methane detection system is constructed. The system can be applied to broad-range concentration detection of methane. Based on the approximation express of the law of Beer-Lambert, detection of methane with various concentration from 0% to 20% is completed using subtraction of background and ratio processing method, as the atmosphere surroundings are treated as background noise. The direct absorption spectra for various concentration is measured using GRIN gas cell, combined with DFBLD. The R5 line of the 2v3 band of methane is selected as the absorption peak. The system is tested online during gas mixing process and the linear relationship between system indication and concentration variation is validated. Also the stability and dynamic response characteristics are confirmed by the experiments. The sensitivity of the system can be adjusted according to the concentration level of various field environments by changing the prism distance using step motor. In the range of 0% to 20% the sensitivity of methane detection can arrive at 0.001%. So the system can be applied to various application fields and adopted as monitoring instruments for coalmine tunnel and natural pipeline.

The Buckling Simulation of Planar W-Form Micro-Spring in MEMS Safety and Arming Device

2015 ◽  
Vol 645-646 ◽  
pp. 796-799
Author(s):  
Fu Fu Wang ◽  
Wen Zhong Lou ◽  
Fang Yi Liu ◽  
Da Kui Wang ◽  
Jun Lu ◽  
...  
Keyword(s):  
Extreme Environments ◽  
Compressive Force ◽  
Fem Analysis ◽  
Axial Direction ◽  
Effect Of Temperature ◽  
Micro Scale ◽  
Response Characteristics ◽  
Temperature Load ◽  
High Or Low Temperature ◽  
The Stability

This paper describes the stability research of MEMS spring used in fuze. The micro-spring in thickness dimension is thin, while the size of axial direction is larger, during compression the micro-spring is prone to suffering buckling and become unstable. In order to consider the extreme environments in launch, this paper aims to carry out buckling simulation in high or low temperature, by using FEM analysis. The effect of temperature load on the micro-spring buckling can be obtained. These researches can provide theory reference for the design applications and reliability analysis of micro-spring, and also lay the foundation for the response characteristics of the micro-scale elastic components under compressive force.

scholarly journals Subloading Surface Model and Experimental Study of Coal Failure under Cyclic Loading

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Si-fei Liu ◽  
Zhi-jun Wan ◽  
Jing-chao Wang ◽  
Shuai-feng Lu ◽  
Tong-huan Li
Keyword(s):  
Cyclic Loading ◽  
Mechanical Response ◽  
Surface Model ◽  
Deformation Characteristics ◽  
Response Characteristics ◽  
Rock Structure ◽  
Specific Strain ◽  
Damage Process ◽  
The Stability ◽  
Number Of Cycles

The fatigue damage of rock is an important factor affecting the stability of rock structure. In this paper, the mechanical response of coal under cyclic loading was studied. In order to accurately describe the deformation characteristics of coal under cyclic loading, an elastic-plastic model of coal based on the theory of subloading surface was established and verified by experiments. The model can well reflect the Mancin effect and ratcheting effect of coal samples, which is basically consistent with the actual deformation characteristics of coal, and the theoretical value and experimental value are in good agreement. At the same time, the cyclic response characteristics of specimens under strain load disturbance were analyzed. The results show that the specific strain disturbance can only cause a certain damage to coal and the area of hysteresis loop decreases first, then stabilizes, and then increases as the number of cycles increases. In addition, the damage factor Dn in the model was analyzed in this paper. Dn, which can accurately describe the damage process of coal, accurately locate the time point of disturbance load change, and has greater sensitivity to coal failure, is helpful to improve the accuracy of the stability judgment of coal structure and ensure the safety of engineering. The above results are of great significance for strengthening the understanding of coal mass instability process and mode under cyclic loading.

scholarly journals Resistivity and AE Response Characteristics in the Failure Process of CGB under Uniaxial Loading

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Tingye Qi ◽  
Guorui Feng
Keyword(s):  
Failure Process ◽  
Peak Stress ◽  
Uniaxial Loading ◽  
Energy Curve ◽  
Cumulative Energy ◽  
Response Characteristics ◽  
Before And After ◽  
The Difference ◽  
Linear Slope ◽  
The Stability

To understand the characteristics of the acoustic emission (AE) and electrical resistivity of cemented coal gangue backfill (CGB) under uniaxial compression, the variations in these characteristics at 1 day, 3 days, and 7 days are analyzed by means of a stress-strain-resistivity-AE test, and the microperformances are investigated. The research results indicate that the AE can reflect the initiation and propagation of cracks and later explain the variation of the resistivity of the specimens under the uniaxial loading. The cumulative energy curve of AE is approximately two straight lines corresponding to the peak stress, and the difference in the linear slope gradually decreased with the increasing curing time due to the lower pore solution content and the compact pore structure. The relationships between the stress and resistivity and the loading condition before and after the peak stress at different curing times were established. Therefore, it is of great significance to predict the stability of the filling body by monitoring the AE and resistivity variations of the filling body. In addition, it is possible to calculate the roof stress using the relation equation between the resistivity and stress.

scholarly journals High Response Performance of a Tuned-Mass Damper for Vibration Suppression of Offshore Platform under Earthquake Loads

2016 ◽  
Vol 2016 ◽  
pp. 1-11 ◽  
Author(s):  
Qiong Wu ◽  
Xilu Zhao ◽  
Rencheng Zheng ◽  
Keisuke Minagawa
Keyword(s):  
Vibration Suppression ◽  
Initial Period ◽  
Offshore Platform ◽  
High Response ◽  
Experimental Investigations ◽  
Offshore Platforms ◽  
Earthquake Loads ◽  
Response Characteristics ◽  
Response Performance ◽  
The Stability

Currently, tuned-mass dampers (TMDs) are widely applied to maintain the stability of offshore platforms in hostile environments; however, the stability system of offshore platforms faces considerable challenges under critical earthquake loads of the initial period. Therefore, this study concentrated on the high response performance of a simple passive TMD system, and numerical and experimental investigations were performed using a 1 : 200-scale prototype. The obtained results indicated that the displacement, acceleration, and their power spectral density all decreased significantly for the offshore platform with the TMD system. By further analyses of its high response characteristics, it was validated that the TMD reactions can commence within the first 3 s of earthquake excitation, while the fundamental natural frequency was consistently tuned for the TMD system dependent on the dynamic magnification factor. The evaluation indices also confirmed that this method is effective in reducing the overall vibration level and the maximum peak values of the offshore platform exposed to earthquake excitations, mainly because of its high response characteristics.

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