NOPR Collection:

Modelling of packed column using artificial neural networks

Mon, 01 Nov 2004 00:00:00 GMT

Title: Modelling of packed column using artificial neural networks Authors: Pandharipande, S L; Mandavgane, S A Abstract: Packed column is an established gas liquid contacting device with many industrial applications. Estimation of liquid hold up and pressure drop as a function of gas and liquid flow rates for single as well as two phase flow are of significance from operational as well as design point of view. Various empirical models have been suggested for the same. Artificial Neural Networks (ANN) are gaining importance in modelling of multivariable, non-linear relationship with high accuracy and even in presence of inadequate data. In present work multi layer perceptron (MLP) ANN with GDR based learning have been developed for estimation of liquid hold up and pressure drop for packed column. The ANN models thus developed are observed to be of good accuracy level, both for training and test data set. Page(s): 820-824

Determination of serum and urinary urate with reusable uricase strip

Mon, 01 Nov 2004 00:00:00 GMT

Title: Determination of serum and urinary urate with reusable uricase strip Authors: Sushma; Rekha; Kumar, Vijay; Suman; Pundir, C S Abstract: Commercial uricase has been immobilized covalently onto alkylamine glass beads affixed on a plastic strip with a conjugation yield of 87mg/g and 11.5% retention of initial activity of free enzyme. Maximum activity of immobilized enzyme was attained at pH 8.8, when incubated at 40°C for 20 min. K_m for uric acid and V_max of immobilized enzyme were 0.15mM and 0.68µmoles H₂O₂/min respectively. A method for uric acid determination in serum and urine was developed using the strip bound enzyme. The method is based on the measurement of H₂O₂ generated from uric acid by using a colour reaction consisting of 4-aminophenazone, p-hydroxybenzoic acid and horseradish peroxidase as chromogenic system. The minimum detection limit of the method was 1.68mg/dl and recovery of added uric acid in urine was 90%. The coefficient of variation (CV) were <5 and <2% for within batch and between batch respectively. The immobilized enzyme lost 50% of its initial activity after its regular uses for over 3 weeks, when stored in 0.05M glycine NaOH buffer, pH 8.8 at 4°C. Page(s): 764-768

Crosslinked polyethylene

Mon, 01 Nov 2004 00:00:00 GMT

Title: Crosslinked polyethylene Authors: Tamboli, S M; Mhaske, S T; Kale, D D Abstract: Properties of polyolefins can be modified by crosslinking process. Different methods of crosslinking and effect of process parameters, selection of crosslinking agents and applications are briefly discussed. Page(s): 853-864

Enzymatic saccharification of cellulosic waste by cellulase system of Cellulomonas uda immobilized on tri(4-formyl phenoxy) cyanurate

Mon, 01 Nov 2004 00:00:00 GMT

Title: Enzymatic saccharification of cellulosic waste by cellulase system of Cellulomonas uda immobilized on tri(4-formyl phenoxy) cyanurate Authors: Khobragade, C N; Sureshkumar, K; Borkar, Prita S; Sagar, A D Abstract: Cellulose is one of the most abundant non-degradable organic compound on earth. Near about half of the municipal and agricultural solid wastes contain cellulose or their derivatives. Saccharification or enzymatic hydrolysis of cellulosic wastes liberates glucose. In the present work, cellulase from Cellulomonas uda was extracted, partially purified by dialysis and immobilized on an organic support namely tri(4-formyl phenoxy) cyanurate. Percentage saccharification of seven different cellulosic waste materials was studied using native and immobilized cellulase systems. Maximum saccharification for both native and immobilized cellulase was observed for sawmill dust or wood dust (4.9 and 2.4% respectively) as compared to other cellulosic waste substrates. Page(s): 816-819