Tai nạn đuối nước ở tỉnh Gia Lai trong thời gian gần đây không chỉ là vấn đề nhức nhối đối với mỗi phụ huynh và học sinh mà còn của cả xã hội vào những dịp hè mùa mưa lũ. Số ca tai trẻ em đứng thứ hai (sau giao thông) có số người tử vong đầu bảng thống kê thương tích toàn tỉnh. Bằng phương pháp điều tra thực nghiệm, kê, bài viết đã làm rõ trạng tại tinh Lai, đồng đánh giá một cách khách quan về...

Aquaculture in the coastal zone has contributed significantly to economic development Giao Thuy district, Nam Dinh province. Therefore, water quality for aquaculture plays a vital role sustainable production. In this paper, iron (Fe) and manganese (Mn) concentrations of district were analyzed during rainy season (September 2017, August 2018) dry at low tide. The results showed that Fe concentra...

In this research, geometrical structures of armchair single walled boron nitride nanotube (SWBNNT) and armchair single walled aluminum nitride nanotube (SWAlNNT) were optimized by Density Functional Theory (DFT) in the gas phase, both having the same length of 5 angstrom and n=9, m=9. B3LYP/6-31G* level of theory have been used to determine and compare electronic properties, n...

A cluster model for active site of nanotube (C48) was presented and investigated the geometricstructure and thermochemical parameters. Quantum-mechanical calculations were performed at theHF / 510-30, 6-310, 6-3 IG• and 6-310" levels of theory in the gas phase and three solvents atfour temperatures. Also, nuclear shielding parameters of the active site of nanotube have been takeninto account us...

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...

In this research, geometrical structures of armchair single walled boron nitride nanotube (SWBNNT) and armchair single walled aluminum nitride nanotube (SWAlNNT) were optimized by Density Functional Theory (DFT) in the gas phase, both having the same length of 5 angstrom and n=9, m=9. B3LYP/6-31G* level of theory have been used to determine and compare electronic properties, n...

P53 is one of the gene that has important role in human cell cycle and in the human cancers too.Models of codon substitution make it possible to separate mutational biases in the DNA fromselective constraints on the protein, and offer a great advantage over amino acid models forunderstanding the evolutionary process of proteins and protein-coding DNA sequences. In thiswork, we investigated abou...

Structural and magnetic properties of purine and pyrimidine nucleotides (CMP, UMP, dTMP, AMP, GMP, IMP) were studied at different levels of ab initio molecular orbital theory. These calculations were performed at the hartree-fock level and density functional B3LYP methods. Geometries were fully optimized by following Cs symmetry restrictions. The standard 6-31G** basis set which includes polari...

The molecular geometry of complex of adenine with 8 water molecules was calculated with Hartree-Fock (HF). The standard 6-31G(d) basis set has been employed. The existence of C-H…O Hydrogen bonds between the water molecules and the hydrophobic part of nucleobase is stablished. We optimized structures and computed interaction energies of all complexes of adenine with water molecules step by step...

Now a day study on boron nitrid nanotubes are in considerable attetion due to their unique properties in different field of science. In this letter, after final optimization, thermodynamic properties analysis, stabilities, electronic structure and nuclear magnetic resonance parameters including σ isotropic and σ anisotropic tensors and asymmetric parameters of 15N and 11B nuclei are calculated....