Growth of carbon nanotubes on fully processed silicon-on-insulator CMOS substrates.

This paper describes the growth of Carbon Nanotubes (CNTs) both aligned and non-aligned on fully processed CMOS substrates containing high temperature tungsten metallization. While the growth method has been demonstrated in fabricating CNT gas sensitive layers for high temperatures SOI CMOS sensors, it can be employed in a variety of applications which require the use of CNTs or other nanomaterials with CMOS electronics. In our experiments we have grown CNTs both on SOI CMOS substrates and SOI CMOS microhotplates (suspended on membranes formed by post-CMOS deep RIE etching). The fully processed SOI substrates contain CMOS devices and circuits and additionally, some wafers contained high current LDMOSFETs and bipolar structures such as Lateral Insulated Gate Bipolar Transistors. All these devices were used as test structures to investigate the effect of additional post-CMOS processing such as CNT growth, membrane formation, high temperature annealing, etc. Electrical characterisation of the devices with CNTs were performed along with SEM and Raman spectroscopy. The CNTs were grown both at low and high temperatures, the former being compatible with Aluminium metallization while the latter being possible through the use of the high temperature CMOS metallization (Tungsten). In both cases we have found that there is no change in the electrical behaviour of the CMOS devices, circuits or the high current devices. A slight degradation of the thermal performance of the CMOS microhotplates was observed due to the extra heat dissipation path created by the CNT layers, but this is expected as CNTs exhibit a high thermal conductance. In addition we also observed that in the case of high temperature CNT growth a slight degradation in the manufacturing yield was observed. This is especially the case where large area membranes with a diameter in excess of 500 microns are used.

On a rational criterion for assigning batch number to processed products of shrimps

Investigations were conducted to find the variability of processed shrimps with respect to two quality characteristics, namely, the numbers of deteriorated and discoloured pieces. Samples were collected for three days from two arbitrarily selected processing factories from Cochin at the pre-freezing stages. Results show that both the quality characteristics vary significantly between different size-grades, but while the variation in the number of deteriorated pieces between days is not significant, the variation in the number of discoloured pieces between days is significant.

Studies on the possible sources of microbial contaminations of processed fishery products

An attempt has been made in the present study to estimate and describe in detail the nature and extent of contamination of processed fishery products. In large scale prawn processing when the preprocess preparation is elaborate, the industry in India has found it advantageous to establish the primary processing centers away from the processing factories. The data collected have clearly indicated that if such processing centers are not properly organized there is a possibility of greater contamination of the products at this stage. The data collected during the course of this investigation have given the basis for the measures to be taken for the maintenance of bacterial quality of prawn during different stages of processing.

Influence of ice on the bacteriological quality of the processed fishery products

The influence of ice on the bacteriological quality of the processed fishery products has been discussed. In almost all the cases ice has been traced to be a major source of contamination depending on the nature of water used for preparing it. The sources of contamination of ice and its remedies have been described.

Use of length-weight relationship in grading processed beche-de-mer

Holothurians, belonging to the species Holothuria scabra, have been collected by diver-fishermen and processed for export. There is an active fishery for these animals in Palk Bay and Gulf of Mannar, off the north-western coast of Sri Lanka. The absence of standardized method of grading has led to unwarranted variation in sale prices and sometimes in loss of foreign exchange in Sri Lanka. In this paper an attempt is made to present a method to grade processed beche-de-mer by using the lenght-weight relationship.

Superconducting properties of Gd-Ba-Cu-O single grains processed from a new, Ba-rich precursor compound

Gd-Ba-Cu-O (GdBCO) single grains have been previously melt-processed successfully in air using a generic Mg-Nd-Ba-Cu-O (Mg-NdBCO) seed crystal. Previous research has revealed that the addition of a small amount of BaO 2 to the precursor powders prior to melt processing can suppress the formation of Gd/Ba solid solution, and lead to a significant improvement in superconducting properties of the single grains. Research into the effects of a higher Ba content on single grain growth, however, has been limited by the relatively small grain size in the earlier studies. This has been addressed by developing Ba-rich precursor compounds Gd-163 and Gd-143, fabricated specifically to enable the presence of greater concentrations of Ba during the melt process. In this study, we propose a new processing route for the fabrication of high performance GdBCO single grain bulk superconductors in air by enriching the precursor powder with these new Ba rich compounds. The influence of the addition of the new compounds on the microstructures and superconducting properties of GdBCO single grains is reported. © 2008 IOP Publishing Ltd.

Flavour components of some processed. fish and fishery products of Japan

A study was conducted to examine the flavour components of some processed fish and fishery products of Japan by gas chromatography-mass spectrometry (GC-MS). In brief the method was to absorb the headspace volatiles at 70°C into the fused silica fibre of needle of the solid phase micro extraction fibre. The absorbed components were injected to the GC-MS. The components were identified by computer matching with library database as well as by authentic standard components. In general the number of flavour components were higher in the processed fish and fishery products (except frozen prawn) than that of the raw fish and prawn. The concentration (quantity) of the f1avour components in processed fish and fishery products was much higher than that of the raw fish and prawn. Smoked salmon and baked salmon possessed double number of flavour components than that of the raw salmon. Smoking resulted the highest number of flavour components followed by baking (grilling) and canning, surimi products (kamaboko and chikuwa), drying and lastly salting. However, freezing and frozen storage resulted loss of flavour components in prawn.

Quality of fishmeal processed from sun-dried fish in a commercial fishmeal dryer

The physical and chemical compositions of the raw materials received and the composition and nutritive values of the finished products in a commercial size fish meal plant employing the dry rendering process were studied and reported in this paper.

Rapapport's broth, a better enrichment medium in the identification of Salmonella from processed frog legs

Live clams (Villorita cyprinoides) collected from their natural beds were packed in different ways like dry pack, tray pack, in oxygenated water (wet pack) and depurated samples in wet pack. It was found that the packaging in l kg lots in 200 gauge polythene bags with oxygen at a temperature of 20°C could keep them live for 4 days. In tray pack without oxygen and water they can be kept alive for 3 days at 20°C. Temperature seems to be the critical factor in the transportation of live clams. At room temperature both dry and wet pack can be kept for 24 h only. Depuration technique does not appear to be useful in prolonging the storage life of clams in live condition as percentage mortality is more at 48 h both at 20°C and room temperature compared to the non-depurated samples.