An Eco-Friendly Method to Get a Bio-Based Dicarboxylic Acid Monomer 2,5-Furandicarboxylic Acid and Its Application in the Synthesis of Poly(hexylene 2,5-furandicarboxylate) (PHF)

Recently, we have developed an eco-friendly method for the preparation of a renewable dicarboxylic acid 2,5-furandicarboxylic acid (FDCA) from biomass-based 5-hydroxymethylfrufural (HMF). In the present work, we optimized our reported method, which used phosphate buffer and Fe(OH)3 as the stabilizer to improve the stability of potassium ferrate, then got a purified FDCA (up to 99%) in high yield (91.7 wt %) under mild conditions (25 °C, 15 min, air atmosphere). Subsequently, the obtained FDCA, along with 1,6-hexanediol (HDO), which was also made from HMF, were used as monomers for the synthesis of poly(hexylene 2,5-furandicarboxylate) (PHF) via direct esterification, and triphenyl phosphite was used as the antioxidant to alleviate the discoloration problem during the esterification. The intrinsic viscosity, mechanical properties, molecular structure, thermal properties, and degradability of the PHFs were measured or characterized by Koehler viscometer, universal tensile tester, Nuclear Magnetic Resonance (NMR), Fourier-transform Infrared (FTIR), X-ray diffraction (XRD), Differential Scanning Calorimeter (DSC), Derivative Thermogravimetry (DTG), Scanning Electron Microscope (SEM), and weight loss method. The experimental evidence clearly showed that the furan-aromatic polyesters prepared from biomass-based HMF are viable alternatives to the petrochemical benzene-aromatic polyesters, they can serve as low-melting heat bondable fiber, high gas-barrier packaging material, as well as specialty material for engineering applications.

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Cuminum cyminum Extracts as Eco-Friendly Corrosion Inhibitor for Mild Steel in Seawater

ISRN Corrosion ◽

10.1155/2013/370802 ◽

2013 ◽

Vol 2013 ◽

pp. 1-7 ◽

Cited By ~ 4

Author(s):

V. Sribharathy ◽

Susai Rajendran

Keyword(s):

Mild Steel ◽

Potentiodynamic Polarization ◽

Electrochemical Impedance ◽

Cuminum Cyminum ◽

Potentiodynamic Polarization Curves ◽

Weight Loss Method ◽

Loss Method ◽

Eis Measurements ◽

The Stability ◽

Good Agreement

The inhibitive effect of Jeera (Cuminum cyminum) plant extracts on the corrosion of mild steel in an aqueous solution of seawater was investigated using potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The stability of the inhibition efficiency of Jeera extracts was examined by weight-loss method. Potentiodynamic polarization curves indicated that the Jeera extract behaves as an anodic type inhibitor. EIS measurements showed that the dissolution process occurs under activation control. The corrosion rates of steel and the inhibition efficiencies of the extract obtained from impedance and polarization measurements were in good agreement. Inhibition was found to increase with an increasing concentration of the plant extract. The results obtained show that the Jeera extract could serve as an effective inhibitor for the corrosion of mild steel in seawater.

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Tetra Schiff Bases as Polyvinyl Chloride Thermal Stabilizers

Chemistry ◽

10.3390/chemistry3010021 ◽

2021 ◽

Vol 3 (1) ◽

pp. 288-295

Author(s):

Dina S. Ahmed ◽

Mohammed Kadhom ◽

Angham G. Hadi ◽

Muna Bufaroosha ◽

Nadia Salih ◽

...

Keyword(s):

Weight Loss ◽

Schiff Bases ◽

Polyvinyl Chloride ◽

Optical Microscope ◽

Atomic Force ◽

Weight Loss Method ◽

Degradation Reaction ◽

Loss Method ◽

The Stability ◽

Stability Time

Tetra Schiff bases were used as thermal stabilizers to enhance the properties of polyvinyl chloride (PVC) when operated at high temperatures. The thermal stability of PVC films doped with Schiff bases was tested by the weight-loss method, Fourier transform infrared (FTIR) spectroscopy, thermal aging test, optical microscope, and atomic force microscope (AFM). Results showed that embedding these additives increased the stability time of the polymer, which decreased the degradation reaction tendency. Furthermore, the primary color of PVC was improved by adding the Schiff bases using oven-aging. In addition, these Schiff bases resulted in a significant reduction in PVC’s conjugated double bonds and, hence, the weight loss.

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A Note on Groove Depth Changes Without Wear

Tire Science and Technology ◽

10.2346/1.2151016 ◽

1980 ◽

Vol 8 (1) ◽

pp. 10-12

Author(s):

F. C. Brenner

Keyword(s):

Weight Loss ◽

Wear Test ◽

Groove Depth ◽

High Rate ◽

Weight Changes ◽

Wear Rates ◽

Weight Loss Method ◽

Loss Method ◽

And Storage ◽

Low Rate

Abstract Tread wear rates during first wear measured by groove depth and weight changes do not always agree. Sometimes, the groove depth method shows a high rate and the weight loss method a low rate. Reported here are experiments designed to determine if grooves show depth changes without wear. Four tires were measured before mounting on a wheel, after mounting and inflation, and after inflation and storage. The mounted and inflated tires showed shallower shoulder grooves and deeper center grooves than the unmounted tires. In a second experiment, tires were measured immediately after a tread wear test and then stored mounted for two weeks before remeasuring. Each groove became deeper, and there was no change in the crown radius of any tire.

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Synergistic and Antagonistic Effects of Sodium Molybdate-Zn2+System

E-Journal of Chemistry ◽

10.1155/2012/368147 ◽

2012 ◽

Vol 9 (4) ◽

pp. 1746-1752 ◽

Cited By ~ 3

Author(s):

J. Wilson Sahayaraj ◽

A. John Amalraj ◽

Susai Rajendran ◽

N. Vijaya

Keyword(s):

Aqueous Solution ◽

Weight Loss ◽

Inhibition Efficiency ◽

Sodium Molybdate ◽

Antagonistic Effect ◽

Protective Film ◽

Antagonistic Effects ◽

Polarization Study ◽

Weight Loss Method ◽

Loss Method

The inhibition efficiency (IE) of sodium molybdate (SM) in controlling corrosion of carbon steel in an aqueous solution containing 120 ppm of Cl-, in the absence and presence of Zn2+has been evaluated by weight-loss method. A synergistic effect exists between SM and Zn2+when the concentration of Zn2+is 25 ppm and above. Inhibition efficiencies obtained are greater than 85%. Antagonistic effect exists between SM and Zn2+when the concentration of Zn2+is 10 ppm and below. The SM-Zn2+system shows excellent IE up to third day. Above third day IE decreases. Acceleration of corrosion takes place. Excellent IE is shown at pH 5,7 and 12. At pH 9, IE decreases since Zn2+is precipitated as Zn(OH)2in the bulk of the solution. Polarization study reveals that SM-Zn2+system functions as a mixed inhibitor. FTIR spectra reveal that the protective film consists of Fe2+-SM complex and Zn(OH)2.

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VARIABILTY AND STABILTY OF TUBER YIELD OF JERUSALEM ARTICHOKE (Helianthus tuberosus L.) / VARIABILIDAD Y ESTABILIDAD DEL RENDIMIENTO DE TUBERCULOS DEL TOPINAMBO / VARIABILITÉ ET STABILITÉ DU RENDEMENT DU TUBERCULE DE TOPINAMBUR

Helia ◽

10.1515/helia.2001.24.35.25 ◽

2001 ◽

Vol 24 (35) ◽

pp. 25-32 ◽

Cited By ~ 4

Author(s):

Janoš Berenji ◽

Vladimir Sikora

Keyword(s):

Tuber Yield ◽

Jerusalem Artichoke ◽

Tuber Size ◽

Yield Stability ◽

Tuber Number ◽

High Yield ◽

Helianthus Tuberosus ◽

Variety Trial ◽

Stable Performance ◽

The Stability

SUMMARYThe objective of this paper was to estimate the genetic and ecological variation as well as the stability of tuber yield per plant, tuber number per plant and tuber size of Jerusalem artichoke based on the results of a variety trial carried out with 20 different Jerusalem artichoke varieties during the period of 1994-2000. Significant genetic as well as ecologycal variation was observed for all of the traits studied. The most promissing varieties showing high tuber yield combined with high yield stability were “BT-4”, “Violet Rennes” and “UKR 4/ 82”. It is encouraging that the highest yielding varieties exibited a rather stable performance over environments.

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The Stability of Potassium Ferrate in Water

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.215 ◽

2014 ◽

Vol 881-883 ◽

pp. 215-218

Author(s):

Kai Luo ◽

Gang Cao ◽

Ming Yu Li ◽

Gang Ren

Keyword(s):

Influencing Factors ◽

Potassium Ferrate ◽

The Stability

The influencing factors of the stability for the potassium ferrate (K2FeO4), including pH, alkalinity, O3, KI, KClO3, KCl, NaClO3and Na2SiO3, were studied in this work. The results showed that the K2FeO4stability in water is best at about pH=10. The higher the alkalinity is, the stronger of K2FeO4stability would be. The O3had no effect to improve the K2FeO4stability. The K2FeO4stability would be best in water with 15mmol/L NaClO3, 10mmol/L Na2SiO3and 9mol/L alkalinity. Under this condition, the K2FeO4content would be 83.28% after 24h.

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Experimental Research on Erosion of P110 Tubing during Perforating

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1073-1076.2244 ◽

2014 ◽

Vol 1073-1076 ◽

pp. 2244-2247

Author(s):

Hu Sun ◽

Zhi Jun Ning ◽

Zu Wen Wang ◽

Zhen Li ◽

Zhi Guo Wang

Keyword(s):

Weight Loss ◽

Erosion Rate ◽

Large Scale ◽

Guar Gum ◽

Electrochemical Corrosion ◽

Low Velocity ◽

Gas Field ◽

Weight Loss Method ◽

Loss Method ◽

Gas Fields

Erosion is a main failure of tubings and downhole tools in Changqing gas field. It is necessary to evaluate the erosion rate for the safety of tubing and strings. In this paper, the erosion of P110 steel, in the 0.2%wt guar gum fracturing fluid which contains sands, is investigated by weight loss method in the self-made jet experiment device. It is indicated that the erosion rate increases with the increment of slurry velocity exponentially. When the slurry velocity is in low velocity area, the electrochemical corrosion of dissolved oxygen dominates in erosion mechanism; when slurry velocity increases into middle velocity area, the weight loss is controlled by the synergism of corrosion-erosion; and when the slurry velocity increases into high velocity area, the weight loss rate is dominantly depended on erosion of particles. The results can provide guidelines for large-scale fracturing work of Changqing gas fields.

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Dissolution of chromium in sulfuric acid

Journal of the Serbian Chemical Society ◽

10.2298/jsc0211777d ◽

2002 ◽

Vol 67 (11) ◽

pp. 777-782 ◽

Cited By ~ 8

Author(s):

Dragutin Drazic ◽

Jovan Popic

Keyword(s):

Corrosion Rate ◽

Room Temperature ◽

Corrosion Potential ◽

Analytical Data ◽

Electrochemical Corrosion ◽

Spectrophotometric Analysis ◽

Weight Loss Method ◽

Loss Method ◽

Anomalous Dissolution

By combining electrochemical corrosion rate measurements and spectrophotometric analysis of the electrolyte it was shown that at room temperature chromium dissolves in deaerated 0.1M Na2SO4 + H2SO4 (pH1) solution as Cr(II) and Cr(III) ions in he ratio Cr(II):Cr(III)?7:1. This process was stable over 4h without any detectable change. The total corrosion rate of chromium calculated from the analytical data is about 12 times higher, than that determined electrochemically by cathodic Tafel line extrapolation to the corrosion potential. This finding was confirmed by applying the weight-loss method for the determination of the corrosion rate. This enormous difference between these experimentally determined corrosion rates can be explained by the rather fast, "anomalous" dissolution process proposed by Kolotyrkin and coworkers (chemical reaction of Cr with H2O molecules) occurring simultaneously with the electrochemical corrosion process.

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Stability of Wheat Genotypes by AMMI and Yield Evaluated under Peninsular Zone of India

Indian Journal of Agricultural Research ◽

10.18805/ijare.a-5701 ◽

2021 ◽

Author(s):

Ajay Verma ◽

G.P. Singh

Keyword(s):

Weighted Average ◽

Principal Component ◽

Efficient Estimation ◽

High Yield ◽

First Year ◽

Wheat Genotypes ◽

Stability Measure ◽

Linear Behaviour ◽

The Stability ◽

Selection Of

Background: Efficient estimation of main and interaction effects under multi environment trials had been carried out by AMMI. Studies with low proportion of the variance explained by first interaction principal component IPCA1 under AMMI analysis had been reported biased interpretation for the stability of the genotypes.Methods: Weighted Average of Absolute scores (WAASB), quantitative stability measure had been recommended for selection of productive genotypes with broad adaptation. The selection of promising genotypes had been assisted by use of superiority index (WAASBY) that considered simultaneous use of yield and stability by allowing variable weighting mechanism for yield and stability.Result: Wheat GW509 and HI1633 genotypes had been identified by stability measure WAASB for the first year. While Superiority index considered stability and high yield settled for HI1633 and Raj4083 genotypes. Analytic measures of adaptability PRVG and MHPRVG observed suitability of HI1633 and Raj 4083. SI expressed positive linear behaviour with yield, MHPRVG and PRVG measures. While stability measure WAASB maintained moderate negative correlation with yield, SI, MHPRVG and PRVG. Wheat genotypes HI1633, HI1641 and HI1646 identified by stability measure for the next year of study. Superiority index selected HI1641, HI1633 and MACS6752 genotypes. SI expressed direct linear relation with yield, MHPRVG and PRVG. Stability measure exhibited indirect relationships with SI, MHPRVG, PRVG and yield Wheat genotypes HI1633, Raj 4083 for first year and HI1641, MACS6752 for the second year of study.

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THERMODYNAMIC PROPERTIES AND CHARACTERIZATIONS OF CHITOSAN NANO-PARTICLES CORROSION INHIBITION ON THE SURFACE OF MILD STEELIN PEAT WATER MEDIA

ALCHEMY Jurnal Penelitian Kimia ◽

10.20961/alchemy.12.1.936.27-35 ◽

2016 ◽

Vol 12 (1) ◽

pp. 27

Author(s):

Maria Erna ◽

Emriadi Emriadi ◽

Admin Alif ◽

Syukri Arief

Keyword(s):

Thermodynamic Properties ◽

Mild Steel ◽

Corrosion Inhibition ◽

Steel Surface ◽

Complex Compounds ◽

Nano Particles ◽

Water Media ◽

Weight Loss Method ◽

Steel Surfaces ◽

Loss Method

The thermodynamic properties and characterizations of corrosion inhibition of chitosan nano-particles on the surface of mild steel in peat water media had been studied using weight loss method at temperatures of 30 - 50 oC. Steel surfaces were characterized by FT-IR spectra and SEM-EDS morphology photos. The research found that the value of DGo approaching -40 kJmol-1. The negative value of Gibbs free energy shows that the adsorption of inhibitor molecules on the surface of mild steel was achemisorption and it occurred spontaneously. Meanwhile, the values of DHo is also negative confirming that the adsoprtion of inhibitor molecules is an exothermic process. The value of DSo obtained is positive, it indicates hat the inhibitor molecules were adsorbed spontaneously on the mild steel surface. The analysis on mild steel surfaces hows that the nano-particle chitosan was adsorbed on the steel surface to form the complex compounds.

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