Showing papers by "Military Academy published in 1991"
TL;DR: In this paper, an algorithm and a computer program for the calculation of the detonation properties of C-H-N-O type explosives are developed on the basis of the steady state model of detonation.
Abstract: On the basis of the steady state model of detonation, using Becker-Kistiakowsky-Wilson equation of state for gaseous products of detonation and Cowan-Fickett equation of state for solid carbon, algorithm and computer program for the calculation of the detonation properties of C-H-N-O type explosives are developed. The program has been tested by the comparison of the calculated data with experimental ones for some high explosives being of different densities and compositions. The calculated data have also been compared with data obtained by program FORTRAN BKW. Both comparisons gave satisfactory agreement.
206 citations
TL;DR: Two pyrazolate-bridged dicopper(II) complexes, [Cu2(LEP)2]2+ (1) and [cu2(BLEP)(OH)]2+(2), have been studied as catalysts for the autoxidation of 3,5-di-t-butylcatechol (DTBC) in this article.
56 citations
TL;DR: In this paper, a reversed phase high-performance liquid chromatographic method was developed for the determination of atenolol in four oral 100 mg atanolol preparations, where an aliquot of the sample is dissolved in a mobile phase consisting of 0.0612 M potassium hydrogen phosphate - isopropanol-tetrahydrofuran (84:10:6) v/v).
Abstract: A reversed phase high-performance liquid chromatographic method was developed for the determination of atenolol in four oral 100 mg atenolol preparations. An aliquot of the sample is dissolved in a mobile phase consisting of 0.0612 M potassium hydrogen phosphate - isopropanol-tetrahydrofuran (84:10:6) v/v). The pH was adjusted to 6.7 with phosphate buffer. Nicotinamide was used as internal standard and chromatographed on a Pinkerton column ISRP (GFF-S5–80) 5 μm, 150 × 4.6 mm i.d. The applied column is convenient for the assay at least 90 samples of atenolol without degrading column performance. The detection was performed at 272 nm. The retention time for atenolol was 5.07 min. The proposed HPLC method was found to be suitable for the rapid and precise routine analysis of atenolol in tablets.
11 citations
01 Jun 1991
TL;DR: In this paper, the noise characteristics and low-light-level imaging capabilities of a stimulated Raman amplifier have been investigated and the Stokes beams carrying spatial structure have been amplified using a collimated pump with a Fresnel number of 17.
Abstract: The noise characteristics and the low-light-level imaging capabilities of a stimulated Raman amplifier have been investigated. Stokes beams carrying spatial structure have been amplified using a collimated pump with a Fresnel number of 17. Both direct imaging of the Stokes signal and Fourier transform imaging of the Stokes signal through the Raman amplifier were used. Evidence of interference between the quantum noise field and the seed-Stokes field is present at the lowest seeding levels.
6 citations
TL;DR: In this article, a regular perturbation expansion of the pre-buckling equilibrium state of the structure in terms of the imperfection magnitude is proposed for both simple and compound buckling.
Abstract: The erosion of the optimal design of structures with buckling constraints, due to the presence of small structural imperfections, is studied. A simple algebraic formula is developed for the imperfection effect on such structures, which is valid for both simple and compound buckling. The formula is based on a regular perturbation expansion of the pre-buckling equilibrium state of the structure in terms of the imperfection magnitude. The developed formula is applied to the reliability-based optimization of a simple structure in a stochastic environment. The strong effect of small structural imperfections in such cases, which may completely invalidate the optimal design of an imperfection sensitive structure, is clearly demonstrated.
4 citations
TL;DR: In this article, the molecular structures of binuclear copper(II) complexes [Cu2REP(μ-OH)(ClO4)2] (4) and [cu2REP (μ-Cl)Cl2](5), in which REP = deprotonated 2,6-bis(1′-(4′-(2″-pyridyl)-2′-thiabutyl))-4-methylphenol, have been characterized by single-crystal X-ray diffraction.
Abstract: The molecular structures of binuclear copper(II) complexes [Cu2REP(μ-OH)(ClO4)2] (4) and [Cu2REP(μ-Cl)Cl2] (5), in which REP = deprotonated 2,6-bis(1′-(4′-(2″-pyridyl)-2′-thiabutyl))-4-methylphenol, have been characterized by single-crystal X-ray diffraction. The former crystallizes in the triclinic space group Pl with a = 10.156(3), b = 12.631(3), c = 25.128(10) A, α = 92.03(3), β = 96.84(3), γ = 108.02(2),° and Z − 2. Complex 5 crystallizes in the monoclinic space group C2/c with a = 12.166(2), b = 11.825(2), c = 18.240(4) A, β = 100.97(2)°, and Z =4. All copper ions are pentacoordinated with ligation to a sulfur, a nitrogen, and the bridging phenolato oxygen of the REP ligand, the exogenous bridge, and a counteranion. The coordination geometry of each copper of the binuclear copper sites is square pyramidal in both 4 and 5. Magnetic susceptibility measurements in the temperature range 6–300 K reveal a strong antiferromagnetic spin exchange in 5 (exchange integral 2J = −460 cm−1). A diamagnetic behavior is observed for 4 according to a similar cryomagnetic investigation. The diamagnetism of 4 is further confirmed by measurements of magnetic susceptibility through Evan's method at room temperature. Complex 4 has no EPR signal. The powder EPR spectrum of 5 shows the typical triplet state characteristics with Δm = ±1 transitions at g = 2.15 and a weaker Δm = 2 transition at half field with g = 4.24.
3 citations
TL;DR: The effects of aluminium hydroxide loading on bone of mice were examined and the calcium level of the same bone samples were determined and aluminium/calcium ratios were evaluated in this study.
Abstract: A number of studies have been carried out on the toxic effect of aluminium on bone mineralization and its relation to calcium and parathroid-hormone metabolism. Exposure to aluminium by the means of either diasylate or ingestion of aluminium hydroxide or both leads to its deposition in tissues, particularly in bone. This deposition blocks incorporation of calcium into osteoids, leading to the osteomalacia characteristic of aluminium-induced bone disease (Drucke 1980; Alfrey 1980; Cournot-Witmer et al 1981; Walker et al 1982; Mayor et al 1980; Cann et al 1979; Cannata et al 1983; Boyce et al 1982). Therefore, the effects of aluminium hydroxide loading on bone of mice were examined. Besides aluminium, the calcium level of the same bone samples were determined and aluminium/calcium ratios were evaluated in this study. The aluminium and calcium measurements have been performed by graphite furnace and flame atomic absorption spectrometry respectively.
3 citations
TL;DR: This study shows that certain HLA antigens may be more frequent in patients with carcinoma of the prostate, and these findings have to be confirmed by other studies.
Abstract: A possible association between HLA antigens and carcinoma of the prostate was searched for in 20 patients and 200 healthy kidney donors. HLA antigens A26, A28, B13, B14, B40, Bw4 and Cw4 were more common in patients with carcinoma of the prostate. The relative risk for HLA B14 was 7.78 (95% confidence interval 7.60–8.13). The relative risk for patients carrying the above antigens (except A28) was higher than 2. This study shows that certain HLA antigens may be more frequent in patients with carcinoma of the prostate. Before drawing any conclusions from these findings, they have to be confirmed by other studies.
1 citations
TL;DR: In this article, ultraviolet and visible spectroscopy were used to study the catecholase activity of two binuclear copper(II) complexes of general formula [Cu2REP(u-X)(Y)2] (1, X =OH and Y=ClO4; 2, X=Y=CI), REP =deprotonated 2, 6-bis(1′-(4′-(2″-pyridyl)-2′-thiabutyl))-4-methylphenol.
Abstract: By means of ultraviolet and visible spectroscopy we have studied the catecholase activity of two binuclear copper(II) complexes of general formula [Cu2REP(u-X)(Y)2] (1, X=OH and Y=ClO4; 2, X=Y=CI), REP =deprotonated 2, 6-bis(1′-(4′-(2″-pyridyl)-2′-thiabutyl))-4-methylphenol. Both complexes promote catalytic autoxidation of 3, 5-di-tert-butylcatechol (3, 5-DTBC) to 3, 5-di-tert-butylquinone (3, 5-DTBQ) in methanol, but not in acetonitrile.
1 citations
TL;DR: In this article, a study on natural convection from a horizontal ice surface melting in pure water was conducted experimentally for the ambient water temperature from 2▿C to 10°C.
Abstract: A study on natural convection from a horizontal ice surface melting in pure water was conducted experimentally for the ambient water temperature from 2▿C to 10°C. Natural convection flow around upward-or downward-facing horizontal ice plate was divided into three regions according to the temperature variation of ambient water. The flow patterns of three regions were no flow, two-dimensional steady laminar flow and unsteady flow. Mean Nusselt number for the upward-facing surface had its maximum value at about 3°C of ambient water temperature. However, in the case of the downward-facing surface it increased as the ambient water temperature increased.
01 Jan 1991
TL;DR: In this article, a new general method is presented for the treatment of the stochastic nature of the structural imperfections, which are practically inevitable in all real structures, and is exemplified with two well known buckling problems.
Abstract: The present paper addresses the problem of the response variability of structures, which experience bifurcation buckling. The buckling strength of such structures may be very sensitive to the small structural imperfections, which are practically inevitable in all real structures. A new general method is presented, which is particularly suitable for the treatment of the stochastic nature of the structural imperfections. The new method is exemplified with two well known buckling problems. The first problem is the buckling of a column on a linear elastic foundation. The shape imperfections of the column are treated as a weakly stationary random process with a pre-specified auto-correlation function. The second problem is the buckling of a thin cylindrical shell under axial compression. The shape imperfections of the shell are treated as a broad-band random Gaussian process with an arbitrarily specified power spectral density function. In both cases, representative numerical results are presented for the purpose of improving our understanding of the response variability of these structures.
01 Jan 1991
TL;DR: In an attempt to obtain new MoAbs against tumor-associated antigens, murine hybridoma-derived IgG1,k MoAb designated as BG-9 is generated against cultured human FO-1 melanoma cells and evaluated the clinical applicability of this MoAb.
Abstract: A major goal of tumor immunology has been the identification of antigens that might be expressed only on malignant tumors or at particular stages of tumor progression. Such antigens would be useful in tumor diagnosis, and the identification of their biological nature might elucidate the mechanisms of the “neoplastic phenotype”. The search for individual tumor cell markers has been best exemplified by monoclonal antibody (MoAb) immunophenotyping of malignant melanoma (1). It appears, at the present time, that the expression of three well-defined antigens, GD2, p75 and p89, is restricted to tumor cells, although the low affinity of MoAbs detecting these antigens may falsely indicate the absence of antigen on control cells (2,3). In an attempt to obtain new MoAbs against tumor-associated antigens we have generated murine hybridoma-derived IgG1,k MoAb designated as BG-9 against cultured human FO-1 melanoma cells. To evaluate the clinical applicability of this MoAb, in the present study we analyzed the distribution of BG-9 antigen in human cell cultures and in surgically removed human tissues.