polyhydroxyalkanoates (phas) are bioplastics derived from renewable resources such as vegetable oils, corn starch, or microbes. the polyhydroxybutyrate (phb) is a short-chain-length pha, and the most important bioplastic produced by certain microorganisms in the presence of excess carbon sources. in this study batch cultivation of alcaligenes eutrophus with the aim of increasing phb production ...

ABSTRACT-Nowadays farmers often use N-fertilizers to increase crop yield, but they lost quickly by leaching causes environmental contaminations that reported as most important source of pollutant. Although biofilters are useful for removing nitrate from drainage water, but many researches show that they need an external carbon source to sustain denitrification. Many researchers study on differe...

Introduction: In electron beam treatment, because of the non-point electron beam source, inverse-square law cannot be applied for dosimetry in different treatment intervals. Therefore, providing source-surface distance (SSD) charts in all clinics is of paramount importance. This study aimed to determine the effective SSD for various electron beam energies and field sizes and to...

the present study was undertaken to investigate and optimize the possibility of xanthan gum production by xanthomonas campestris ptcc1473 in 500ml shake flasks on the second grade date palm. using an experimental response surface methodology (rsm) coupled with a central composite design (ccd), three major independent variables (nitrogen source, phosphor source and agitation rate) were evaluated...

Effective management of nitrateimpacted aquifers requires identifying the sources of nitrate to the aquifer, and understanding the transport and fate of nitrate within the aquifer. Source identification is crucial to effective source mitigation; conversion of residential septic systems to sewer in a rural community will be ineffective if the primary source of nitrate contamination is agricultur...

A reciprocity inequality is derived, involving the effective size of a planar, secondary, Gaussian Schell-model source and the effective angular spread of the beam that the source generates. The analysis is shown to imply that a fully spatially coherent source of that class (which generates the lowest-order Hermite-Gaussian laser mode) has certain minimal properties.

the main problem of solid waste management system in tehran is to handle a large amount of waste (7.641 ton/day in 2008). therefore, source reduction can be introduced as one of the first priority for solid waste management in tehran. this research represents the first attempt to quantify the source reduction potential in the city, and subsequently, outlines the principle guidelines, legislatio...

The conceptual design determines the success of the final product quality and competition of market. The determination of design parameters and the effective method to resolve parameters contradiction are the key to success. In this paper, the concept of HOQ products designed to determine the parameters, then using the TRIZ contradiction matrix and inventive principles of design parameters to s...

Inclusion-exclusion is an effective method for computing the volume of a union of measurable sets. We extend it to multiple coverings, proving short inclusion-exclusion formulas for the subset of R covered by at least k balls in a finite set. We implement two of the formulas in dimension n = 3 and report on results obtained with our software.