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The inversion reaction coordinate of free amino acids (alanine, aspartic acid) have been computationally calculated by semi-empirical methods AM1. A transition state for free alanine and aspartic acid were obtained as a three membered ring in which the α-C-H and α-C-CH3 are slightly elongated, 1.2 and 2.17 Å respectively in the alanine transition state. The activation energy of alanine is 77.52 kcal/mol...
Isatins are synthetically versatile substrates, where they can be used for the synthesis of a large variety of heterocyclic compounds. In this, a convenient method has been developed for the conversion of Indoles into Isatins and some heterocyclic derivative were synthesised such as 5- nitro-1H-indole-2,3-dione, 2-methylquinoline-4-carboxylic acid which may be used as raw material for drug synthesis...
The drinkable water in oasis region of Algeria contains high quantity of fluoride which causes dental fluorosis. To reduce fluoride, we have chosen a sample with the biggest content of fluoride among many sources in order to coagulate it with FeSO4·H2O. After that the parameters influencing (concentration, pH, temperature) are studied to choose the best conditions for better reduction.
The work contains some of the elements of adequate quantum theory of impact phenomenon. These elements form the prelude to verification of the existent non-adequate theory of the impact phenomenon. At first a correct definition of impact has been formulated. For comparison, the interpretation of the elastic impact according to the existent knowledge is given. Then, taking advantage of the new correctly...
A pot experiment on an acid brown soil was conducted in 1998-2001. Three multicomponent fertilizers were applied: Polifoska 8, Polifoska 16 and Polimag 306, at the rates of 0.5; 1.0; and 1.5 g N per pot. The total forms of cadmium were determined in dry matter of perennial ryegrass with the use of ASA method. The contents of these elements were higher in the fertilized variants as compared to the...
Photons contribute electromagnetic field that accompanies the gravitational field. These two fields may be, mutually, transformed through a kind of transformation matrix dependent upon the boundary conditions of the system. In this work trial would be made to find the nature of this transformation matrix considering a super system of photon in which both fields are unified. The unification of electromagnetic...
Striking similarities in properties of lanthanides make their separation a difficult task. Development of highly selective analytical reagent hexane-2,5-dione-bis(ethylenediamine) HDBE that forms brown coloured complex with Ce(IV) which is quantitatively extracted into xylene at pH 6.4. Transfer of extracted complex to organic phase is very fast (<1min.). Optimum concentration of reagent required...
Some 2’-hydroxyphenylchalcones have been synthesized under microwave irradiation by Claisen-Schmidt condensation between substituted 2-hydroxyacetophenone and substituted benzaldehydes using catalytic amount of SiO2-H3PO4. These chalcones were established by their physical constants and spectroscopic data published earlier. The UV, IR, 1H NMR and 13C NMR spectral data of these chalcone have correlated...
2,2'-[1,2-phenylenebis(nitrilomethylidene)]bisphenol (BSOPD) is synthesized in the laboratory and characterized by NMR, IR and elemental analysis for its purity. This reagent forms a yellow complex with U(VI) which can be quantitatively extracted into chloroform at pH 10. This complex in chloroform shows an intense absorption peak at 413.0 nm. It is observed that Beer’s law is obeyed in the range...
Urbanization is the cause of many changes which is taking place in the environment, including those found in the catchment Three multicomponent fertilizers were applied: Polifoska 8, Polifoska 16 and Polimag 306, at the rates of 0.5; 1.0; and 1.5 g N per pot. The total forms of nickel were determined in dry matter of perennial ryegrass with the use of ASA method. The contents of these elements were...
Ultrasonic velocity is measured experimentally at 3MHz frequency in the binary liquid mixture containing aniline and anisole at different temperatures over the entire composition range and theoretical values of ultrasonic velocity have been evaluated by using Nomoto’s relation, Impedance relation, Van Dael ideal mixture relation. These theoretical values are compared with the experimental values....
The paper discusses the groundless use of mathematics. This question has been explained mainly based on example of the so called d`Alembert’s rule which unfortunately still functions in science none the less it has been based on a fiction, contrary to the truth cognition as the fundamental purpose of science. That pejorative feature of the mentioned paradigm is marked very clearly in the paper to...
Thin films of ZnO0.7NiO0.3 have deposited on glass substrates at room temperature by using thermal evaporation technique under vacuum 10-5 mbar. The optical properties and dispersion parameters of the films have been studied. Changes in direct optical energy band gap of films were confirmed before and after annealing. The optical energy gap Eg decreased from 3.11 to 2.86 eV with increasing of annealing...
A pot experiment on an acid brown soil was conducted in 1998-2001. Three multicomponent fertilizers were applied: Polifoska 8, Polifoska 15 and Polimag 306, Travit at the rates of 0.5; 1.0; and 1.5 g N per pot. The total forms of phosphorous were determined in dry matter of perennial ryegrass with the use of ASA method. The contents of these elements were higher in the fertilized variants as compared...
Urbanization is the cause of many changes which is taking place in the environment, including those found in the catchment. A pot experiment on an acid brown soil was conducted in 1998-2001. Three multicomponent fertilizers were applied: Polifoska 8, Polifoska 15, Polimag 306 and Travit at the rates of 0.5; 1.0; and 1.5 g N per pot. The total forms of nitrogen were determined in dry matter of perennial...
This article presents a new class of copolymerizable photoinitiators containing vinyloxycarbonyl groups, known such as organic carbonate or carbamate. Novel copolymerizable photoinitiators have been prepared through the reaction between vinyl chloroformate and hydroxyl groups containing photoreactive derivatives such as benzophenone-, acetophenone-, benzoine-and anthrachinone-derivatives. The main...
Amino-acid derived compounds, for example N-α-lauroylarginine ethyl ester (LAE), N-α-myristoylarginine ethyl ester (MAE) and a 1:1 mixture of N-α-myristoylarginine ethyl ester with monolaurin (MAE + MLN) are examined for their cytotoxicity towards L929-Mouse connective tissue to explore their use as microbicidal agent, in comparison to sodium dodecylsulfate (SDS) as an anionic control detergent. MTT...
The astronomical contributions of Sir Arthur Eddington have sometimes been distracted by his philosophy and his derivation of ~1079 for the total number of elementary particles in the universe. However, assumptions employed to obtain the universal mass in a volume of ~1079 m3 produce values remarkably commensurate with ~1079 protons. The congruence between the calculated gravitational forces for rest...
This manuscript describes a novel class of copolymerizable benzophenone photoinitiators and their influence on viscosity and molecular mass of acrylic pressure-sensitive adhesives (PSAs) during radical solvent polymerization and shrinkage of acrylic PSAs coated on PVC film and crosslinked using UV radiation.
The progress of civilisations causes changes in the water catchment areas lakes. aquatic waters are order - phosphorus and nitrogen compounds. Level of activity alkaline phosphatase (APA) has an important impact on the chemical and biological processes taking place in the aquatic environment. APA belongs to a group of indicators, who tells us about the extent limitations to development of biomass...
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