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This study investigates ballistic response of a developed perforated armour plate against 12.7 mm armour piercing tracer projectile. Experimental as well as numerical studies were carried out and the penetration of the projectile through a base aluminium plate was determined with and without the perforated armour plate. The armour piercing projectiles were able to penetrate the base armour plate in successive impacts. However, the combination of the perforated and base armour plates was able to stop the penetration of the armour piercing projectile. A finite element method-based numerical model was developed to investigate the defeating phenomenon of perforated and base armour plate combination. It was observed that the asymmetric impact of the projectile core did not produce large enough bending to fracture the core. However, the high hardness of the developed perforated plate was able to shatter the projectile core in multiple fragments which were then unable to penetrate the base armour plate. Craters of varying depths were observed on the impact side of the base armour plate. The research showed that the selected structural steel can be successfully used for ballistic protection. [ABSTRACT FROM AUTHOR]

The bacterial infection and generation of free radicals inside the body are serious threats to human health globally and researchers show their serious concern for these issues. Thus, in this study, an attempt has been made to control bacterial growth and scavenge the ABTs free radicals. ZnO-NPs were synthesized by an economical method, and the characteristics were investigated using a range of analytical techniques. These methods included FTIR, SEM, EDX, XRD, and TEM. The agar-well diffusion process has been followed to control the growth of selected bacteria and the ABTs free radicals have been scavenged using a standard protocol. The effect of the dose on both activities has been studied where the results has explore that the effectiveness of the ZnO-NPs gradually increases with increasing concentration. [ABSTRACT FROM AUTHOR]

When water is adsorbed on Pt(111) above 135 K several different ice structures crystallize, depending on the thickness of the ice layer. At low coverage water forms extended islands of ice with a ([Square_Root]37×[Square_Root]37)R25° unit cell, which compresses as the monolayer saturates to form a ([Square_Root]39×[Square_Root]39)R16° structure. The [Square_Root]39 low-energy electron diffraction (LEED) pattern becomes more intense as the second layer grows, remaining bright for films up of 10–15 layers and then fading and disappearing for films more than ca. 40 layers thick. The ice multilayer consists of an ordered [Square_Root]39 wetting layer, on which ice grows as a crystalline film which progressively loses its registry to the wetting layer. Ice films more than ca. 50 layers thick develop a hexagonal LEED pattern, the entire film and wetting layer reorienting to form an incommensurate bulk ice. These changes are reflected in the vibrational spectra which show changes in line shape and intensity associated with the different ice structures. Thin amorphous solid water films crystallize to form the same phases observed during growth, implying that these structures are thermodynamically stable and not kinetic phases formed during growth. The change from a [Square_Root]39 registry to incommensurate bulk ice at ca. 50 layers is associated with a change in crystallization kinetics from nucleation at the Pt(111) interface in thin films to nucleation of incommensurate bulk ice in amorphous solid water films more than 50 layers thick. [ABSTRACT FROM AUTHOR]

The structure of the mixed p(3×3)-(3OH+3H2O) phase on Pt{111} has been investigated by low-energy electron diffraction-IV structure analysis. The OH+H2O overlayer consists of hexagonal rings of coplanar oxygen atoms interlinked by hydrogen bonds. Lateral shifts of the O atoms away from atop sites result in different O–O separations and hexagons with only large separations (2.81 and 3.02 Å) linked by hexagons with alternating separations of 2.49 and 2.81/3.02 Å. This unusual pattern is consistent with a hydrogen-bonded network in which water is adsorbed in cyclic rings separated by OH in a p(3×3) structure. The topmost two layers of the Pt atoms relax inwards with respect to the clean surface and both show vertical buckling of up to 0.06 Å. In addition, significant shifts away from the lateral bulk positions have been found for the second layer of Pt atoms. [ABSTRACT FROM AUTHOR]

In much of the developing world today, particularly among countries populated by Muslim majorities, a dreadful ideological disease has erupted, spreading as an epidemic through several generations already. Arising out [...]

CO adsorption on Ni{110} and on hydrogen precovered Ni{110} surfaces at 180 K has been studied by FT-RAIRS. On a clean Ni{110} surface CO adsorbs at on-top sites upto a coverage of 0.7 ML. At higher coverages the on-top CO band at 2060 cm-1 decreases in intensity with a concomitant increase in a band at 1960 cm-1 which shifts up in frequency. The (2×1)p2mg structure at 1.0 ML CO coverage shows a single band at 1998 cm-1 attributed to CO tilted at bridged sites. FT-RAIRS of CO adsorption on H precovered Ni{110} surfaces shows complex CO site switching within different CO and H coverage regimes. A model is presented involving compression of H into islands of high coverage and both mixed H and CO and unmixed CO islands are formed. CO adsorbs in the unmixed CO islands the same as that on clean Ni{110}. Within the mixed H/CO islands the first layer nickel atoms reconstruct and a new hydrogen desorption state is observed. The CO site switching observed by FT-RAIRS within the various H and CO coverage regimes is discussed in terms of a dominant indirect interaction. [ABSTRACT FROM AUTHOR]

Chlorine nitrate absorption dynamics and uptake is calculated on ordered ice and HCl trihydrate coats at temperatures below 150K. The reaction is observed using thermal molecular band with mass spectrometric identification of gas phased products and temperature-planned desorption to detect adsorbed species.

Thermal molecular beam measurements with FTIR spectroscopy were used to characterize the products and study the kinetics of HCI adsorption and incorporation into crystalline and amorphous ice. It was found that HCI adsorption on water ice below 120 K forms a surface layer of a HCI hydrate with a saturation uptake of one HCI for each water molecule in the surface bilayer.