POWDER COATING PROCESS PARAMETERS FOR A TRANSFER EFFICIENCY MODEL

The trajectories of charged powder particles in a powder coating system are governed by the electrostatic, gravitational and aerodynamic forces acting on the particles. A mathematical model of particle trajectories inside a powder coating booth must consider (1) the aerodynamic flow field, (2) particle size and charge distributions, (3) the electrostatic field distribution, and (4)the geometry of the target. Our approach is to employ a grid generation and flow solver to examine the air flow pattern and an iterative technique where the Charge Simulation Method can be used to compute the electric field strength and the Method of Characteristics can be used to compute the charge density in the gun-to-target region. The electrostatic forces due to the deposited powder layer and image charge are to be taken into account to determine if the particle will deposit on the substrate or not. The model is applied to the geometry of a high-voltage electrode consisting of a long thin rod with a hemispherical end cap and a grounded flat disk substrate. An experimental system to measure transfer efficiency, with the ability to control various parameters effecting transfer efficiency, has been developed to verify the theoretical model. The simulation results can provide valuable information concerning particle deposition and optimization of transfer efficiency. This paper describes (1) system parameters involved in modeling the transfer efficiency, (2) an approach to develop such a model with preliminary data on the simulation of particle track, and (3) experimental data on the real-time measurements of first pass transfer efficiency.     

Production and composition of microbial fat from Rhodotorula glutinis

The fatty acid, sterol and hydrocarbon compositions of oil produced by a new strain of Rhodotorula glutinis isolated from soil and grown on molasses, were determined. The major constituent fatty acids were: palmitic (37%) oleic (47%) and linoleic (8%). The major sterols were campesterol (42%) and stigmasterol (27%) and the major hydrocarbons were n-C₂₃ (37%), iso-C₂₉ (30%) and n-C₂₁ (19%). Minor constituents in each class of lipids were also detected and estimated. The oil produced was 54% on a dry weight basis. The fatty acid composition was found to be close to that of palm oil.     

Fatty acids of the mud skipper boleophthalmus boddaerti

The fatty acid composition of the body and the liver lipids of Boleophthalmus boddaerti, a mud skipper fish belonging to the Gobiidae family, have been determined by argentation column chromatography (a.c.c.) and gas-liquid chromatography (g.l.c.). The levels of 20:5ω3 (ca 14%), a biologically important fatty acid, was found to be considerably high. Other major component acids were, 16:0, 18:0, 16:1, 18:1, 20:3ω9, 22:5ω3 and 22:6ω3. Besides, a large number of minor components were identified and estimated. The liver lipid contained unusually high levels (ca 90%) of non-saponifiables.     

Effect of the in vivo priming regimen for peripheral blood stem cells (PBSC) mobilization on in vitro generation of cytotoxic effectors by IL-2 activation of PBSC in a murine model

Subjective quality of life (QOL) has often been assessed through questionnaires or structured interviews focusing on the person's satisfaction with various life domains. In particular, most QOL instruments for psychiatric patients are based on this concept. We report on a study casting some doubts on the rationale of this approach. We investigated the QOL of 48 chronic schizophrenic outpatients with a long-term disease history (at least 20 years) using a German version of the Lancashire QOL Profile. The interrelations between general life satisfaction, satisfaction with specific life domains, psychological well-being and psychopathology were studied using correlation analysis and multiple linear regression. Of the life domains assessed, only two, namely social relations and health, contributed significantly to the patients' general life satisfaction, while the others (including work, leisure, family relations and housing) did not. The subscales on psychological well-being (self-esteem, affective state) as well as psychopathology were found to be more closely associated with general life satisfaction than almost all life domains considered. The findings are discussed with regard to the specific situation of the group of patients investigated. They give indications that the life domain approach to measuring QOL has its limitations, in particular when applied to patients having adapted to a very restricted everyday life.     

Highly potent synthetic polyamides, bisdistamycins, and lexitropsins as inhibitors of human immunodeficiency virus type 1 integrase

Alignment of the available human immunodeficiency virus type 1 (HIV-1) viral DNA termini [U5 and U3 long terminal repeats (LTRs)] shows a high degree of conservation and the presence of a stretch of five or six consecutive adenine and thymine (AT) sequences approximately 10 nucleotides away from each LTR end. A series of AT-selective minor-groove binders, including distamycin and bisdistamycins, bisnetropsins, novel lexitropsins, and the classic monomeric DNA binders Hoechst 33258, 4'-diamino-2-phenylindole, pentamidine, berenil, spermine, and spermidine, were tested for their inhibitory activities against HIV-1 integrase (IN). Although netropsin, distamycin, and all other monomeric DNA binders showed weak activities in the range of 50-200 microM, some of the polyamides, bisdistamycins, and lexitropsins were remarkably active at nanomolar concentrations. Bisdistamycins were 200 times less potent when the conserved AAAAT stretch present in the U5 LTR was replaced with GGGGG, consistent with the preferred binding of these drugs to AT sequences. DNase I footprinting of the U5 LTR further demonstrated the selectivity of these bisdistamycins for the conserved AT sequence. The tested compounds were more potent in Mg+2 than in Mn+2 and inhibited IN50-212 deletion mutant in disintegration assays and the formation of IN/DNA complexes. The lexitropsins also were active against HIV-2 IN. Some of the synthetic polyamides exhibited significant antiviral activity. Taken together, these data suggest that selective targeting of the U5 and U3 ends of the HIV-1 LTRs can inhibit IN function. Polyamides might represent new leads for the development of antiviral agents against acquired immune deficiency syndrome.     

Dynamic schedule execution in an agent based holonic manufacturing system

The present paper deals with the negotiation based task allocation to the resources for preparing dynamic scheduling in an agent based holonic control framework. The scheduling priority is developed by Multi Objective Optimization on the basis of Ratio Analysis (MOORA) technique under Fuzzy Multi Criteria Decision Making (FMCDM) environment considering several attributes. The well-known Contract Net Protocol (CNP) is followed for the purpose of task allocation by negotiation and cooperation, where message based communication is accomplished by eXtensible markup language (XML) using J2EE. Different Document Type Definitions (DTDs) are developed for intended applications. Necessary modifications in the scheduling arising out of changes in the volume-mix are made by a distributed cooperative problem-solving algorithm to meet the demand without violating the deadline. The algorithm is implemented using HTML code in front-end with Java Server Page (JSP) through Apache Tomcat 6.02 server. It is advocated that the cooperation based teamwork coupled with higher flexibility and agility is the key to success to remain unperturbed and provide reasonably good solution in the face of disturbances and stands superior to its hierarchical counterpart.     

BIOGAS RECOVERY FROM A THERMALLY TREATED SEWAGE SLUDGE BY A FIXED-BED ANAEROBIC BIOREACTOR

Biogas recovery from the anaerobic digestion of sewage sludge which is discharged from municipal wastewater treatments generally requires a large scale digester owing to the slow biodegradability of the sludge compounds. To achieve an effective methanogenesis from the sludge as the raw materials, thermal pretreatmenls of the sludge were conducted to improve the sedimentation efficiency of the treated sludge and the filtrate obtained was anaerobically digested in fixed-bed bioreactors with baked clay, melted slug and rhyolitic lava.

Methane formation from the intact activated sludge (10g/l) was 11 methane/I after 25-day fermentation without heat treatment (control), whereas in the case of treating for 1 h at 121°C, 2.1 I methane/I was produced from the whole treated sludge (10g/l) and 2.91 methane/1 was produced at pH 4 at the same heat treatment. However, no more methane was produced when the sludge was treated with 0.1 N NaOH or H₂SO₄ at 121°C for 1 h although lower fatty acids were accumulated.

The filtrates from heat treated sludge either at 121°C for 1 h at pH 4 or at 121°C for 1 h contained 2200 and 4400 mg COD/I, respectively. The filtrates obtained were anaerobically digested in fixed bed reactors. For the former, at COD loading 32.4g/l/day, the methane production rate was 2.91/l/day with 52.6% of COD reduction at 1.5 h of hydraulic retention time, whereas, for the latter, methane production rate was 2.11/1/day with 26.2% of COD reduction at 2.4 h retention time (COD loading 47.8).

It would be concluded that the heat treatments of discharged sludge from aeration tank might be a promising means for the treatment of activated sludge since the heat treatment could decrease the specific resistance of filtration of sludge and the filtrate discharged could be easily converted to methane as a fuel energy.