The physical and chemical properties of Pyrazole and Pyrazoline molecules were theoreticallystudied by Gaussian 03, software with NMR and Molecular orbital calculations at B3LYP/6-31G andB3LYP/6-31+G(d) levels, in gas phase and solution. In this study a comparison effect of threesolvents with different dielectric constants on Pyrazole and Pyrazoline molecules in aspect energyinteraction between...

Use of precision farming technologies requires better understanding of soil variability in physical, hydraulic and chemical properties. Some of that variation is natural, some is the result of the management history of the field. So, to match agricultural inputs and practices to site-specific conditions, the factorial kriging algorithm (FKA) was used to analyze spatial variability in some soil ...

our main objective in the present study was to assess the spatial variation of chemical and physical water properties. prior to the design of groundwater quality monitoring networks, it is essential to investigate the spatial structure of the groundwater quality variables. a case study is presented which used ground water quality observations from groundwater domestic wells in the dameghan, ira...

Tin-Zinc alloy coatings have many applications because of their unique properties such as corrosion resistance, solderability and flexibility. In this study, the effect of current density, temperature and pH on chemical composition, cathodic current efficiency, morphology and structures of the coatings was investigated. The results illustrated that, at low current densities (<0.5 mA/cm2), the c...

Rotational isomeric state theory has been used to calculate mean-square unperturbed dimensions (r2>0 and dipole moments (/~> of ethylene-vinyl chloride copolymers as a function of chemical composition, chemical sequence distribution, and stereochemical composition of the vinyl chloride sequences. As was previously found for several other copolymeric chains, (/z2> is much more sensitive to chemi...

This work presents an experimental study realized at the materials laboratory of the University of M’sila. It consists to vary the percentage of the pozzolanic admixture (waste bricks) in cement by the substitution method (partial replacement of the clinker by the calcined clay). The characteristics of cement at anhydrous state and the hydrated state (chemical composition, specific weight and f...

our main objective in the present study was to assess the spatial variation of chemical and physical water properties. prior to the design of groundwater quality monitoring networks, it is essential to investigate the spatial structure of the groundwater quality variables. a case study is presented which used ground water quality observations from groundwater domestic wells in the dameghan, ira...

Plants employ highly variable chemical defenses against a broad community of herbivores, which vary in their susceptibilities to specific compounds. Variation in chemical defenses within the plant has been found in many species; the ecological and evolutionary influences on this variation, however, are less well-understood. One central theory describing the allocation of defenses in the plant i...

Considerable inter- and intraspecific variation with respect to the quantity and composition of plant natural products exists. The processes that drive this variation remain largely unknown. Understanding which factors determine chemical diversity has the potential to shed light on plant defenses against herbivores and diseases and accelerate drug discovery. For centuries, Cinchona alkaloids we...

IUPAC has published a number of recommendations regarding the reporting of nuclear magnetic resonance (NMR) data, especially chemical shifts. The most recent publication [Pure Appl. Chem. 73, 1795 (2001)] recommended that tetramethylsilane (TMS) serve as a universal reference for reporting the shifts of all nuclides, but it deferred recommendations for several aspects of this subject. This docu...