Heat transfer through electrolytic solutions under the action of electrolytic currents

Heat transfer rates from an electrically heated thin platinum wire in dilute NaOH and Na₂CO₃ solutions of different concentrations have been measured under the influence of electrolytic currents, using a sensitive Kelvin double bridge. In the low concentration region, the rate of heat transfer is initially found to increase with concentration and then to decrease with further increase in concentration. An explanation of these results on the basis of the behaviour of the thermal boundary layer surrounding the hot wire electrode is suggested. It has been indicated that these results can be employed to improve the performance of boiler systems and electro chemical machining processes.     

An improved estimator for population proportion using inverse sampling

In this paper we have proposed a method for the determination of prefixed sample size (m) used in the estimation of population proportion proposed by Haldane (1) for specified permissible error with a given confidence coefficient and an improved estimator for population proportion using inverse sampling scheme.     

Application of defect simulation as a tool for more efficient failure analysis

In modern VLSI processes, increasing process complexity has resulted in an exponential rise in the costs of thorough failure analysis. In this paper, we present a defect simulation-based failure analysis methodology, which can be used to significantly reduce both costs and turn-around time for failure analyses. The methodology is based on the ability to generate a defect dictionary, which can relate defect characteristics to some easily measurable symptoms of defect occurrence.     

Comparison study of chitosan,EDTA, eugenol and peppermint oil for antioxidant and antimicrobial potentials in chicken noodles and their effect on colour and oxidative stability at ambient temperature storage

The aim of this study was to investigate the antioxidant and antimicrobial activity of chitosan, EDTA, eugenol and peppermint essential oil and their effect on color and oxidative stability of chicken noodles stored at 35 ± 2 °C. Results indicated that among the four preservatives, eugenol treatment exhibited higher ABTS⁺ (2-2-azinobis-3ethylbenthiazoline-6-sulphonic acid) radical cation activity (89.54%), DPPH (1, 1-diphenyl-2-picrylhydrazil) (51.30%) and superoxide anion scavenging activity (66.82%). Total polyphenol content was also higher in eugenol treated samples. The samples treated with eugenol and chitosan protect against an increase lightness (L-value) and decrease in redness (a) and yellowness (b) values during storage. However, pH value was highest in noodles with chitosan treatment while TBARS (2-thiobarbituric acid reacting substances) and FFA (Free fatty acids) contents were lowest in noodles with eugenol irrespective of storage periods. Eugenol treatment also showed positive impact on microbiological quality and sensory attributes. In conclusion, eugenol has more potential as a natural preservative to increase shelf-life of chicken noodles.     

Transient and steady‐state conduction in ethyl cellulose (EC)–poly(methyl methacrylate) (PMMA) blends

Transient discharging currents and steady‐state conduction in solution‐grown ethyl cellulose (EC)–poly(methyl methacrylate) (PMMA) blends measured as a function of temperature (30–80 °C) and field strength (10–100 kV cm⁻¹) are reported. Transient currents are found to follow the Curie–VonSchweidler law, characterized by different slopes in short‐ and long‐time regions, having different decay constant values lying between 0.75–0.99, and 1.68–1.95. The corresponding activation energies are found to increase with time of measurement of discharge current. Isochronal characteristics (ie current versus temperature plots at constant times) constructed from the data seem to reveal a broad peak observed at 60 °C. The dependence of dark current at different temperatures (30–80 °C) in a metal (1)–EC–PMMA blend–metal (1)/(2) system on the applied voltage in the range 10–100 kV cm⁻¹ has also been studied; the current is found to be strongly temperature dependent. Dipole polarization and space charge resulting from trapping of injected charge carriers in energetically distributed traps and induced dipoles created because of the piling up of charge carriers at the phase boundary of the heterogeneous components of the blend are considered to account for the observed transient currents. The results of current–voltage measurement on blends are interpreted to show that the low‐field steady‐state conduction is ohmic in nature, and in high fields the charge carriers are generated by field‐assisted lowering of coulombic barriers at the traps and are conducted through the bulk of the material by a hopping process between the localized states by a Jonscher–Ansari Poole–Frenkel mechanism. The modified P–F barrier is calculated to be 1.89 × 10⁻¹⁹ J (1.18 eV), 1.92 × 10⁻¹⁹ J (1.20 eV) and 1.95 × 10⁻¹⁹ J (1.22 eV) for P₁, P₂ and P₃ blends, respectively. © 2000 Society of Chemical Industry     

FPGA Implementation of Cross Virtual Concatenation Transmitter/ Receiver for Data Transmission over Next Generation SDH Systems

Cross Virtual Concatenation is the new technique proposed for bandwidth efficient transmission of data over SDH networks. SDH networks came into existence for reliable voice transmission. As the demand of data traffic grew in wide area networks, new technologies were developed and standardized for data transmission over SDH networks. The technologies used namely, GFP (generic framing procedure), VCAT (virtual concatenation) and LCAS (link capacity adjustment scheme) enable network operator to provide integrated voice and data services over their legacy SDH infrastructure. Data packets are encapsulated using framing protocols GFP. VCAT is a process of distributing the GFP framed data payload in number of virtual channels of same capacity forming a Virtually Concatenated Group (VCG). LCAS is used for dynamic bandwidth allocation. LCAS enhances the VCAT scheme with hitless in service addition and removal of VC’s to/from the VCG.VCAT combines homogeneous virtual channels together which in some cases limits the performance of VCAT. This paper describes the implementation of new concatenation technology named cross virtual concatenation (CVC), which combines heterogeneous VC’s together to utilize the SDH bandwidth more efficiently. CVC implementation requires only end node equipments to be upgraded as VCG members travel through the link similar to the conventional VCAT. This paper proposes FPGA implementation of transmitter and receiver circuits for 100 Mbps Ethernet data transmission over next Generation SDH systems using CVC, where two types of VC’s namely VC-3 and VC-12 are used for data transmission. Total Transmission delay is calculated as 125 μs. There is no complexity added at the receiver side due to this delay. The receiver is designed for 32 ms differential delay compensation which can be increased up to maximum 256 ms by increasing the buffer size at the receiver.