This study involves adding nano materials and interaction with cement mortar behavior for several mortar samples under variable curing time with constant water to cement ratio (W/C = 0.5). The effects of adding nano materials on the microstructure of cement mortar were studied by (Scanning Electronic Microscopy (SEM) and X-Ray (for samples at different curing time 28 and 91 days. Small ratio replacements of nano particles (SiO₂ or Al₂O₃) were added to Ordinary Portland Cement (OPC) type (I). The percentage of nano materials additives replacement by weight of ordinary Portland cement includes (1, 2, 3, 4 and 5%) for both types of nano materials with constant (W/C) ratio, also the amount of the fin

The analytical results of the failure types of six limestone islands in the Ha Long bay of Vietnam have been identified. The calculated results of safety factor for 03 plane failure blocks lie within 0.9 and 2, have high potential failure. The analytical results have been also simulated these islands in three-dimensional space and have been also analyzed their potential failure on the fracture surfaces. The results obtained in this paper have important significance for planning and development of the Ha Long bay area, as World Natural Heritage, Quang Ninh province of Vietnam.

This work presents the characteristics of plasma produced by fundamental wavelength (1064 nm) Q- switched Nd:YAG laser on Ag:Ni alloy in distilled water were investigated at different laser energies by optical emission spectroscopy technique. The size of produced nanoparticles from Ag:Ni target in distilled water were studied, by x-ray diffraction, UV-visible absorbance and atomic force microscopy, at different laser energies. Spectroscopic measurements show that electron temperature and electron density increase with increasing laser energy. It was found from AFM measurements that the produced nanoparticle size decrease from 97.13 nm to 71.20 nm, while XRD shows that the crestalline size decrease from 15.5 nm to 9 nm with increasing pul

Pseudomonas aeruginosa was isolated from various clinical samples included urine, sputum, stool, ear, wound & burn swabs. Detection of the ability of local isolates to produce staphylolysin enzyme was studied, on Tryptic soya agar + 0.2% (wt./vol.) of heat killed Staphylococcus. aureus at temperature 100oC. medium and the diameters of lysis zone ranged from 5-22mm, then the isolate P16 was chosen to extract staphylolysin A (LasA) and its specific activity reaches 8.59 unit /mg protein, whi1e the isolate P5 was chosen to extract staphylolysin D (LasD) where it's specific activity reaches 0.66 unit /mg protein since the two isolates were the most production of enzyme. Staphylolysin enzyme was extracted by cooling centrifugation and par

In this study, detection of uricase production from Pseudomonas aeruginosa
isolates was done by applying colorimetric method, Uricase was purified from the
most potent isolate by precipitation using ammonium sulphate (80% saturation) then
purification was achieved using DEAE –Cellulose ion exchange and Sepharose 6B
gel filtration chromatography column, 16.4% of total enzyme was recovered with
specific activity 2337.5U/mg and 22.21folds of purification. Characterization of
uricase involved detection of optimal conditions for uricase activity, the maximal
activity was obtained at temperature 45ºC,while uricase appeared to be stable at
40ºC. Uricase showed optimal activity at pH 9 while pH stability was in the

      In this paper, the optical emission spectrum (OES) technique was used to analyze the spectrum resulting from the (CdO:CoO)  plasma in air, produced by Nd:YAG laser with λ=1064 nm, τ=10 ns, a focal length of 10 cm, and a range of energy of 200-500 mJ. We identified laser-induced plasma parameters such as electron temperature (T_e) using Boltzmann plot method, density of electron (n_e), length of Debye (λ_D), frequency of plasma (f_p), and number of Debye (N_D), using two-Line-Ratio method. At a mixing ratio of X= 0.5, the (CdO:CoO) plasma spectrum was recorded for different energies. The results of plasma parameters caused by laser showed that, with t

      This study shows the effects of copper material electrode, applied voltage, and different pressure values on electrical discharge plasma. The purpose of the work is the application of the spectral analysis method to obtain accurate results of nitrogen plasma parameters. By using the optical emission spectroscopy (OES), many N₂ molecular spectra peaks appeared in the range from 300 to 480 nm. Also, some additional peaks were recorded, corresponding to atomic and ionic lines for nitrogen, target material, and hydrogen, in all samples. The electron density (n_e) was calculated from the measurement of Stark broadening effect, which was found to decrease with increasing pressure from 0.1 mba