Interoperability issues in heterogeneous network management

The presence of dissimilar network models and standards necessitates interoperability as a means of achieving ubiquitous connectivity and management. The primary focus of this paper is to identify interoperability issues, independent of the network management model, which form the basis for developing interworking paradigms. Network Management and Interoperability related concepts and terminology are introduced and a generic network management framework is presented. Based on the generic framework, interoperability issues for developing paradigms are identified systematically. Different paradigms for interoperability are described and compared. The techniques used by these paradigms in addressing the issues identified are discussed.     

Effect of CuO on the sintering and cryogenic microwave characteristics of (Zr0.8Sn0.2)TiO4 ceramics

The effect of CuO on the sintering temperature, microstructure and microwave dielectric properties of (Zr_0.8Sn_0.2)TiO₄ (ZST) modified with 1 wt% of ZnO has been investigated. Microwave dielectric properties of ZST ceramics are measured from cryogenic to room temperatures (15–290 K). Crystallite sizes of sintered ZST ceramics as derived from XRD are in the 30–50 nm range. The addition of CuO effectively reduced the sintering temperature to 1300 1C, possibly due to liquid-phase effects. Addition of CuO did not cause any secondary phases up to 1.5 wt% of CuO. The dielectric constant (ε_r) and temperature coefficient of resonant frequency (ε_f) of ZST ceramics do not significantly vary with temperature, whereas the unloaded quality factor (Q_u) changes noticeably. It is found that the Q_u factor of the sample without CuO decreased with increase in temperature, whereas the samples with addition of CuO up to 1.0 wt% showed less dependence on temperature. The Q_u factor of CuO-free ZST is 15,000 and that of ZST with 0.5 wt% of CuO is 11,800 at 15 K. The Q_u factor while measured at room temperature ranged between 2900 and 7000. Efforts were made to understand whether the increase in Q_u factor at both cryogenic and room temperatures is the result of intrinsic or extrinsic factors.     

Distribution of <Superscript>210</Superscript>Pb in the surface sediments of major rivers of coastal Kerala,South India

The distribution of ²¹⁰Pb in the sediment samples of major rivers of coastal Kerala, namely, Bharathapuzha, Periyar, and Kallada, was studied systematically. The activity of ²¹⁰Pb was estimated through ²¹⁰Po by radiochemical separation and subsequent deposition on a silver disc. The α-activity was then counted using a ZnS(Ag) counter of 30% efficiency, and the activity was calculated. The mean activities of ²¹⁰Pb in the sediment samples of Bharathapuzha, Periyar, and Kallada rivers were found to be 13.5 ± 1.2, 89 ± 3, and 61 ± 2 Bq kg^–1, respectively. Good correlation was found between the ²¹⁰Pb activity and organic matter percentage and clay content for Periyar and Kallada rivers.     

Anticorrosion Potential of Flectofenine on Mild Steel in Hydrochloric Acid Media: Experimental and Theoretical Study

Journal of Failure Analysis and Prevention - The inhibition effect of Flectofenine on corrosion of mild steel in 1M HCl solution was investigated by using traditional weight loss method and...     

Synthesis and characterization of nanostructured CaSiO3 biomaterial

Here we report a successful preparation of nanostructured calcium silicate by wet chemical approach. The synthesized sample was characterized by various physico-chemical methods. Thermal stability was investigated using thermo-gravimetric and differential thermal analysis (TG-DTA). Structural characterization of the sample was carried out by the X-ray diffraction technique (XRD) which confirmed its single phase hexagonal structure. Transmission electron microscopy (TEM) was used to study the nanostructure of the ceramics while homogeneous grain distribution was revealed by scanning electron microscopy studies (SEM). The elemental analysis data obtained from energy dispersive X-ray spectroscopy (EDAX) were in close agreement with the starting composition used for the synthesis. Superhydrophilic nature of CaSiO₃ was investigated at room temperature by sessile drop technique. Effect of porous nanosized CaSiO₃ on early adhesion and proliferation of human bone marrow mesenchymal stem cells (BMMSCs) and cord blood mesenchymal stem (CBMSCs) cells was measured in vitro. MTT cytotoxicity test and cell adhesion test showed that the material had good biocompatibility and promoted cell viability and cell proliferation. It has been stated that the cell viability and proliferation are significantly affected by time and concentration of CaSiO₃. These findings indicate that the CaSiO₃ ceramics has good biocompatibility and that it is promising as a biomaterial.     

Modeling Water Flow Through Carbon Nanotube Membranes with Entrance/Exit Effects

Carbon nanotube–based membranes have gained significant attention due to their transport efficiency and wide range of applications, including molecular sieving and sensing. Recently, in order to attain high transport rates, many studies have focused on reducing membrane thickness. A reduction in membrane thickness results in the dominance of entrance/exit effects over surface effects, particularly for carbon nanotubes (CNTs), due to their hydrophobicity. However, experimentally obtained nanoscale flow rate data span a wide range, and entrance/exit effects are often neglected when analyzing these data. In this study, we modeled the water flow rate through various lengths and radii of CNTs using molecular dynamics simulations while also taking entrance/exit effects into consideration. Based on viscosity and slip length calculations, a water flow model is proposed that covers various lengths and radii of CNTs. Moreover, the enhancement factor of CNT membranes is reassessed using entrance/exit effects. The results of this study can be used for the optimal design of ultraefficient CNT membranes for potential applications such as water filtration.     

Trace Elements in the Si Furnace-Part II: Analysis of Condensate in Carbothermal Reduction of Quartz

Silicon feedstock for production of solar-grade silicon should be as pure as possible to decrease the cost of manufacturing of solar cells. Impurities in quartz, carbonaceous materials, electrodes, and refractories are mostly present in the form of oxides. These oxides can be reduced to volatile gaseous compounds in presence of SiO(g) and CO(g) atmosphere and potentially leave the furnace or stay in the condensed reaction products, metal, and slag. This work investigates the conditions under which volatile impurities report to the gas phase in laboratory experiments with lumpy and pelletized mixtures of SiO₂, SiC, and Si at 1923 K and 2123 K (1650 °C and 1850 °C), respectively, were carried out. The volatile compounds were generated by the reduction of quartz and collected in the form of condensate. The effects of the reaction temperature, quartz type, charge composition, pellets, and lumps on the composition of the condensate were studied. The trace elements in the charge input, reacting charge, and condensate were analyzed using inductively coupled plasma (ICP)-mass spectroscopy (MS) and X-ray diffraction (XRD). CO(g) and SiO(g), which are the major components in reduction reactions, formed four types of condensate: white, brown, green, and orange. The condensate constituents were amorphous SiO₂, 3C:SiC, Si, and α-quartz. Each impurity present in the quartz charge entered the gas phase during quartz reduction and was detected in the condensate. Al and Fe show limited volatility. The volatility of Mn, P, and B depends on the charge mix: a higher P_CO enhances the concentration of these elements in the gas phase. Fluid inclusions, common in hydrothermal quartz, enhance the distribution of the contaminants to the gas phase. Industrial campaigns on Si and Fe-Si production confirm the experimental results.