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European chemical bulletinVol. 8., No.7. (2019.)

Tartalom

Classical chemical sciences

  • D. S. Bhagat ,
    R. P. Pawar ,
    A. B. Tekale ,
    S. G. Pande ,
    R. R. Rangari ,
    I. V. Suryawanshi ,
    P. B. Chavan ,
    S. N. Tapase ,
    A. A. Sahu :

    Ultrasound-assisted synthesis of a chemosensor from benzoyl chloride and diethylenetriamine in acetonitrile was carried out and the product structure was confirmed by UV-VIS and FT-IR spectroscopy. The synthesized chemosensor interacts with metal ions and produces a notable change in colorimetric measurements. It is observed that as the concentration of metallic ions increases, absorbance also increases, thus the chemosensor can be used for quantitative estimation of metal-ion content.

    Keywords: chemosensor,forensic application,ultra-sonication,coordination complex

  • Vaishanavi S. Jambhorkar ,
    Aniket P. Sarkate ,
    Aishwarya P. Rajhans ,
    Kshipra S. Karnik ,
    Sajed H. Ansari ,
    Shambala U. Chavan ,
    Yogesh W. More ,
    Dattatraya N. Pansare :

    A new method of amides synthesis under catalyst-free condition has been developed by using aldehydes and aminopyridines. The amides were synthesized by using different aldehydes and aminopyridines using ethanol as a solvent and hydrogen peroxide as oxidant. The method helps in preparation of amides which were acquired in good yield within 4-5 h using conventional heating. The reaction is catalyst-free. The developed method is easy, economical, and flexible.

    Keywords: benzamides; aldehydes; aminopyridines; hydrogen peroxide; catalyst-free

Materials and environmental chemistry

  • Soran Kamal ,
    Sleman Qadir :

    Utilizing impedance spectroscopy, chitosan-based solid polymer electrolyte containing CF3SO3Ag was investigated for their electric modulus properties. Using the highest conductivity sample, the lowest conductivity relaxation time (τσ) was determined. The high capacitivity of the material is shown by the electrical modulus of the real part. A non-Debye type relaxation is predicted by the asymmetric peak of electric modulus's imaginary part (M"). Utilizing Argand plot, a deformed arc for the relaxation times distribution is demonstrated. Silver nanoparticles formed from silver ions causes a rise in the values of M' and M" above 358 K. The ultraviolet-visible (UV-vis) absorption and complex impedance of silver nanoparticles in chitosan-silver triflate solid electrolyte are temperature dependent. Transmission electron microscopy (TEM) confirmed the silver nanoparticles formation. The dynamical relaxation process for a particular composition is proven by the scaling behavior of M" spectra to be independent of temperature. The conductivity relaxation is shown by a β exponent to be non-exponential.

    Keywords: silver; electrical modulus; polymer electrolyte; chitosan; silver triflate

  • Wan M. Khairul ,
    Saidatul Radhiah Ghazali ,
    M. I. N. Isa ,
    Adibah Izzati Daud ,
    Rafizah Rahamathullah :

    Alkoxy substituted arylthiourea derivatives provide excellent electronic properties due to the presence of rigid π-systems within their molecular framework. This study introduces a new thiourea derivative, N-(decyloxyphenyl)-N‘-(4-chlorobenzoyl)thiourea (1A), belongs to the compounds with general formula A-ArC(O)NHC(S)NHAr-D (A is an aryl group containing chloro (-Cl) substituent, in which acts as electron acceptor, while D represented as –OCnH2n+1, the alkoxy chain tail acts as electron donor). Due to its characteristic of D-π-A system, alkoxy thiourea derivatives are applied as a dopant in Carboxymethyl Cellulose (CMC) host material to form a conductive biopolymer solid polymer electrolyte (SPE) film. The formation of a biopolymer-thiourea complex (1A-CMC) has been analyzed through Fourier Transform Infrared (FTIR) spectroscopy and X-ray diffraction (XRD) to determine the interaction between CMC and thiourea derivative in the form of film as well as Electrical Impedance Spectroscopy (EIS) for their ionic conductivity behavior. The highest conductivity at ambient temperature (303K) exhibits 1.44 x 10-7 S cm-1 for CMC-thiourea complexation featuring chloro-substitution (1A). Indeed, biopolymer electrolyte materials featuring thiourea derivative as a dopant has great potential to be developed as an electrical conductor. Due to these findings, these so-called molecular wires candidate has opened wide possibilities to be applied in many microelectronic devices in the near future.

    Keywords: thiourea, carboxymethyl cellulose, conductive thin film

Chemical and biological aspects of life

  • Olawale H. Oladimeji ,
    Aniekeme E. Essien ,
    Arthur J. Sheriff ,
    Taiwo E. Alemika :

    Cinnamic acid, chemically known as 3-phenyl-2-propenoic acid is has a broad spectrum of pharmacological actions including antioxidant activity. The esterification and selective reduction of the acid led to ethyl cinnamate and cinnamyl alcohol, respectively. Cinnamic acid demonstrated a poor antioxidant activity (IC50) of 1.2 μg mL-1 while ethyl cinnamate and cinnamyl alcohol elicited activities of 0.64 μg mL-1 (moderate) and 0.84 μg mL-1, respectively. The obtained results indicate that esterification enhances the antioxidant activity of cinnamic acid.

    Keywords: Cinnamic acid; esterification; selective-reduction; ethyl cinnamate; cinnamyl alcohol

  • Shazia Khanum Mirza ,
    Sayyad Sultan Kasim :

    The increasing demand for ready-to-drink juices has led to challenges for food distributors regarding the safety and quality of their foods hence food additives are added to foods to keep them fresh, control its pH and improve the flavor, texture, color or taste and appearance. The present work aimed at the quantitative determination of additives as ascorbic acid and citric acid in a variety of fruit juices of India using the classical titration method, to check whether the current uses of these additives are according to the Food Safety and Standard Authority of India (FSSAI). Consuming too much amount of vitamin C may increase the amount of oxalate in your kidneys, which has the potential to lead to kidney stone problem. The high intake of citric acid leads to stomach pain, diarrhea, nausea or vomiting, increased sweating and fast heart rate. In this study, we have selected 14 different popular juice samples which are consumed most by Indian children. Each sample was analyzed for organoleptic or physical tests such as color, texture, flavor, taste and pH. These findings indicated that the current use of ascorbic acid and citric acid in all juices by the fruit juice industry is below the permitted limit of FSSAI and are safe for the consumption by Indian children.

    Keywords: Fruit juices; acidity regulators; citric acid; antioxidants; ascorbic acid.