HEAT AND MASS TRANSFER RELATIONS FOR CROP DRYING

In present communication, an attempt has been made to study the heat and mass transfer for crops namely wheat and gram. The removal of moisture from the crop was determined under simulated conditions and it was used to develop heat and mass transfer relation using linear as well as multiple regression analysis. The observations were recorded for relative humidity, temperature of crop and air and for moisture evaporated. Experimental error in terms of per cent uncertainty was calculated for recorded data which is in the range of 20 - 30 per cent for forced convection and natural cooling, respectively.     

Crosstalk reduction in mixed-signal 3-D integrated circuits with interdevice layer ground planes

We show nearly 8 dB of crosstalk reduction using ground planes between active device layers in three-dimensional (3-D) integrated circuits. Our experimental work utilizes two planes of MOS transistors with tungsten or polysilicon ground planes designed to attenuate crosstalk. Theoretical simulations, using an electromagnetic solver, and the experimental results are consistent with analytical results. The key result verified is that a ground plane, whose footprint shadows the device area, is sufficiently large for effective attenuation. The interdevice layer ground plane provides an effective means to achieve crosstalk reduction in 3-D mixed-signal/RF integration because of simple fabrication and high coupling isolation.     

Simplified loss analysis and comparison of full-bridge,full-range-ZVS DC-DC converters

The loss of zero-voltage-switching (ZVS) of active switches has been a serious limitation of full-bridge (FBZVS) converters. Many techniques have been proposed in the past to extend the range of ZVS operation over the wider and also the full range of operation. However, in these techniques ZVS is achieved at the expense of additional conduction loss in active switches and losses in the auxiliary components. In this paper, the analysis for the additional losses in various full-range FBZVS DC-DC converters and their comparative evaluation is reported. Closed form expressions are derived for average value of device currents and losses. The loss curves for various topologies are plotted and compared. The analytical results are found to be consistent with the experimental efficiency tests performed on 500 W, 100 kHz prototype. It is concluded that a recently proposed new topology has the least penalty of additional losses.     

Electron microscopic observations of Bi and Tl bearing cuprate high temperature superconductors

The second generation of high temperature superconductors typified by Bi₂Sr₂Ca _n−1Cu _n O_2n+4 and Tl₂Ba₂Ca _n−1Cu _n O_2n+4 exhibits curious structural properties which have direct relevance to the superconducting behaviour particularly transition temperature (T _c ). The present paper reports on investigations of structural properties at microlevel in Bi-bearing HTCS. We have found curious structural characteristics which manifests itself in the form of transformation froma _p ×a _p ×c to (2)^1/2 a _p ×(2)^1/2 a _p ×c through the loss of calcium atoms and the formation of five-fold modulated phase alongb through the loss of Ca and Sr atoms. We have also found the evidence of high periodicities (n=4) Bi₂Sr₂Ca₃Cu₄O₁₂. The microstructural characteristics of HTCS showing the higherT _c (R=0) ∼ 120 K exhibits unusual characteristics.     

Bioactive Carbohydrates and Peptides in Foods: An Overview of Sources,Downstream Processing Steps and Associated Bioactivities

Bioactive peptides and carbohydrates are sourced from a myriad of plant, animal and insects and have huge potential for use as food ingredients and pharmaceuticals. However, downstream processing bottlenecks hinder the potential use of these natural bioactive compounds and add cost to production processes. This review discusses the health benefits and bioactivities associated with peptides and carbohydrates of natural origin and downstream processing methodologies and novel processes which may be used to overcome these.     

Vacuum-Deposited Thin Film of Aniline–Formaldehyde Condensate/WO3·nH2O Nanocomposite for NO2 Gas Sensor

A hydrated tungsten oxide (WO₃·nH₂O)-embedded aniline–formaldehyde condensate (AFC/WO₃·nH₂O) nanocomposite thin film was prepared on an indium tin oxide (ITO)-coated glass surface via vacuum-deposition technique. The resulting AFC/WO₃·nH₂O/ITO thin film was characterized using ultraviolet–visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), and electron microscopy (SEM). The composite thin film exhibited a crystalline surface morphology containing nanocrystals of WO₃·nH₂O with a diameter ranging from 15 to 20 nm. The AFC/WO₃·nH₂O/ITO film allowed for the low potential detection of NO₂ gas at a concentration range from 0 to 9000 ppm. The NO₂ gas sensing characteristics were studied by measuring the change in the current with respect to concentration and time. The current of the AFC/WO₃·nH₂O/ITO film linearly increased with an increase in concentration of NO₂ gas with a response of ~20 s.     

Superconductivity at 4 K in Pd-Deficient Layered Ta2Pd x S6

In the present short letter, we report on the low dimensional 4d and 5d transition metals-chalcogenide based compounds i.e., Ta2PdxS6, showing semiconducting to superconducting transition at around 4K with their upper critical fields outside the Pauli paramagnetic limit. It seems couple of different superconducting phases do exist in these new set of compounds. Our short letter in this regards is thought provoking, asking to explore various unearthed possible new superconducting phases in (Nb/Ta)2Pdx(S/Se/Te)y systems.     

Efficient solutions to various routing issues involved in mobile ad hoc bio-sensor networks: applying appropriate motion trajectories

Ad hoc bio-sensor networks have a very characteristic structure with three types of nodes: the command centre, the sensor nodes (animals such as rats) and the relaying nodes. We have taken up such networks and measured the throughput of such systems and suggest ways in which the throughput can be increased. It was also found that to increase the throughput of such systems, no sophisticated routing techniques or expensive transmission techniques are needed. This can be achieved by simply adopting the appropriate motion trajectories of the nodes. We have also explained the structure of these networks in detail and the routing issues involved in these networks. A Hot-Spot problem at the command centre has also been discussed. The suggestions of appropriate motions target this problem and show how an even distribution of nodes can alleviate this problem to a large extent. In addition to this, a constraint on the number of messages the sensor node can send per unit time can also make the network more efficient.     

Apoptosis in batch cultures of Chinese hamster ovary cells

One of the main problems in the culture of Chinese Hamster Ovary (CHO) cells continues to be the inability to maintain the viability of the cultures over an extended period of time. The rapid decline in viability at the end of the culture is exacerbated by the absence of serum. In trying to reduce the extent of death in these cultures, we first tried to determine the mode of death. We found that more than 80% of the cells in a standard serum-free batch culture of CHO cells in suspension died via apoptosis--as evidenced by condensed chromatin and the appearance of a characteristic DNA ladder. Furthermore, when protein synthesis was inhibited using cycloheximide, the cells underwent rapid apoptosis indicating that death proteins were present in greater abundance than survival proteins in our CHO cells. Cell lysate from CHO cells showed evidence of cysteine protease (caspase) activity. Caspases of the Interleukin-1-beta-Converting Enzyme (ICE) family, e.g., CPP32, Mch-1, etc., have been implicated in the apoptotic process. Surprisingly, a caspase peptide inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp-fluoro-methyl-ketone (z-VAD.fmk), was unable to substantially extend the life of a serum-free batch culture of CHO cells. In addition, z-VAD.fmk was only marginally able to extend viability in response to withdrawal of growth and survival factors, insulin and transferrin. In both these instances, z-VAD.fmk was able to prevent cleavage of caspase substrates, but not protect cells from death. However, we found that bcl-2 expression was able to significantly extend viabilities in CHO batch culture. Bcl-2 expression also substantially extended the viability of cultures in response to insulin and transferrin withdrawal. These results provide interesting insights into the pathways of death in a CHO cell.     

Near optimal process plan selection for multiple jobs in networked based manufacturing using multi-objective evolutionary algorithms

The networked manufacturing offers several advantages in current competitive atmosphere by way of reducing the manufacturing cycle time and maintenance of the production flexibility, thereby achieving several feasible process plans. In this paper, we have addressed a Multi Objective Problem (MOP) which covers-minimize the makespan and to maximize the machine utilization while generating the feasible process plans for multiple jobs in the context of network based manufacturing system. A new multi-objective based Territory Defining Evolutionary Algorithm (TDEA) to resolve the above computationally challenge problem have been developed. In particular, with two powerful Multi-Objective Evolutionary Algorithms (MOEAs), viz. Non-dominated Sorting Genetic Algorithm (NSGA-II) and Controlled Elitist-NSGA-II (CE-NSGA-II) the performance of the proposed TDEA has been compared. An illustrative example along with three complex scenarios is presented to demonstrate the feasibility of the approach. The proposed algorithm is validated and the results are analyzed and compared.