Journal of Scientific & Industrial Research

VOLUME 61

                        NUMBER 8

AUGUST 2002

CONTENTS

Review Papers

571

Development of 157 nm photoresist polymers for the F2 laser lithography









Niranjan Karak

Attempts to investigate the problems, significance, and the recent development strategies of photoresist polymers for 157 nm lithography.

586

COX-2-inhibitor  ¾ a new class of analgesic and anti-inflammatory drugs





Mohd Amir & Shikha Kumar

Discusses the development of COX-2 inhibitors and their introduction in the market as useful drugs.

Papers

599

Speaker identification from voice using
neural networks

























Bijita Biswas & Amit Konar

Presents a novel scheme for speaker identification from the generic unformatted voice samples of the personnels and thus is unique in all respects. Soft computing tools, such as fuzzy logic and neuro-computing are gaining their importance in pattern recognition. Speaker identification from the voice of the subjects also belongs to this category of problems, and thus most of the available tools of soft computing may be utilized to handle this problem. Here three distinct models of artificial neural nets, such as the back-propagation (BP) algorithm and the self-organizing feature map (SOFM) neural nets and the radial basis function (RBF) neural net and BP combination are employed to handle the present pattern recognition problem. Compares the performance of the two neural techniques mentioned above with respect to the application of the neural nets in the specific problem of speaker identification. An analysis of the comparison reveals that the BP algorithm with momentum term in the gradient descent learning expression has a good convergence to the global minima of the error surface and thus is amenable for speaker identification even with small Gaussian noise around the measured input voice instance.

607

Thermal modeling of crystal growth by the Czochralski method including radius control









































Amit Kumar, Jyotirmay Banerjee &
K Muralidhar

Anlysis of thermal phenomena in the crystal grown by Czochralski process is addressed. The model is employed for deriving conditions under which the crystal radius during growth can be kept a constant. Two parameters that influence the size of the crystal radius to these parameters. The mathematical model is based on one-dimensional unsteady heat conduction in the solid phase with radiation to the enclosure. The model can predict the time-wise variation of the pull velocity and the base tempature so that the radius of the crystal can be maintained constant to within a prescribed tolerance. Results derived show that the crystal radius exhibits greater sensitivity to the pull velocity as compared to the crucible base temperature.

617

Soil physical and chemical properties as influenced by flyash addition in soil and yield of wheat











S K Sharma, Naveen Kalra & G R Singh

Field experiments are conducted in villages around National Capital Power Project (NCPP), Dadri, Uttar Pradesh and Indian Agricultural Research Institute (IARI) Farm, New Delhi during 1995-96 to evaluate flyash addition effects on soil environment and yield of wheat crop (Triticum aestivum L). Flyash application levels are up to 50t/ha. Yield of wheat increases up to 20t/ha ash addition, and declines thereafter but still higher than the yield under no flyash addition treatment. Flyash treated plots have marginally higher uptake of trace  elements. Flyash application in soil shows reduced hydraulic conductivity and improved moisture retention at field capacity and permanent wilting point. The pH value of soil decreases, whereas electrical conductivity, organic carbon, and sodium increases in accordance with flyash addition in soil. Phosphorous, potassium and calcium decreases in flyash treated plots. The changes in soil properties might be due to modifications in the macro-and micro pore size distribution which contributes to increased yield of wheat.

621

Potato phenol oxidases immobilized s-triazine containing dialdehyde : an efficient
biocatalysts for bioremediation of phenols













R N Gacche, V S Ghole, C N Khobragade & A D Sagar

Polyphenol oxidase (PPO) and peroxidase enzymes extracted from potato and immobilized on s-triazine are exploited for the detoxification phenols from industrial effluents. It is found that the phenol content of industrial effluent is reduced from 168 to 38  mg/mL within three and half hours treatment with immobilized phenol oxidases.

625

Vaginal pheromone and other compounds in mung-bean aroma





































R L Brahmachary & Mahua Ghosh (Basu)

Reports probably a first attempt to identify the molecules which impart a most desirable, characteristic aroma to certain varieties of mung bean of Bengal  ¾ a valuable indigenous natural product that may be on the verge of extinction. In boiled, or fried mung bean of the two best strains, strong evidence for the presence of 2-acetyl-1-pyroline, the molecule responsible for the aroma of Basmati rice and one component of tiger pheromone, is obtained. GCMS analysis and computerized library search further suggest the presence of six volatile compounds in the CCI4 extracts of even the second grade mung bean samples. Two of  these are a male-attracting vaginal pheromone and a puberty-delaying pheromone in rodents.

630

Modified cold percolation method for
extracting oil from oil seeds






















V C Kalia, Sudhama Lal & Rashmi

Presents a modified cold percolation method for regulating extraction of oil from oil seeds, particularly suitable for enzymatic studies.

Book Reviews

635

·          Markets for technology  ¾ the economics of innovation and corporate strategy
         Reviewer: N Mrinalini

·          Photosynthesis: Photobiochemistry and Photobiophysics
         Reviewer: Prasanna Mohanty

Sci-Tech Update

639

·          Software engineering in the academy

·          Monoclonal antibodies-arsenal against major diseases?

·          World’s most advanced air traffic control center

·          E-book library software for professionals

·          Intellectual property rights protection may help local innovation in the long-term

·          Driverless taxi service

·          Red wine helps to prevent heart disease

·          Eucalyptus could be worth weight in gold

·          A new nano device developed

·          Methods to reduce water consumption

·          Sugar ‘n’ space

·          New type of self-healing polymer developed

·          Breaking DNA base pairs by remote control

·          One catalytic step converts benzene to phenol

·          Overlook yeast genes found

·          Chlorinated organics form as plants decay

·          First divalent organothulium complex developed

  • Tobacco plants help TNT clean up