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Maldistribution of two-phase flow in evaporators is known to significantly affect their performance. To reduce refrigerant maldistribution, a pressure-swirl atomizer is used to distribute R-134a in the header of a typical evaporator. A phase-doppler particle analyzer is used to characterize the spray along the centerline of the header for 1, 2, and 3 g/s total mass flow rate. The thermodynamic quality is varied in the header from 0% to 15%. The centerline droplet size is found to decrease with increasing quality and to decrease with increasing distance downstream of the nozzle. Flow distribution is found to be more uniform when the atomizer is used as the expansion device when compared to a typical expansion valve and pipe inlet. [ABSTRACT FROM AUTHOR]

The usefulness of exogenous nicotine as a factor in the induction of morphogenesis in a tobacco tissue culture medium has been demonstrated. Nicotiana rustica callus cell cultures were grown on a modified Murashige and Skoog medium with 2 mg/l indoleacetic acid (IAA) and 0.2 mg/l kinetin (MMS). Root morphogenesis was induced in roller tube callus cell cultures and solid callus cell cultures grown on MMS without kinetin supplemented with 10-100 mg/l nicotine. Optimal nicotine concentration for root induction was 50 mg/l. Other tests using varying combinations of IAA, kinetin and nicotine produced no obvious morphogenesis, although some changes in the amount of callus growth and endogenous protein concentration did correlate with nicotine concentration relative to the presence of IAA and/or kinetin. In liquid MMS medium, 14C-nicotine was primarily incorporated into the protein fraction of cultured cells while primarily incorporated into the cell wall and/or cell membrane fraction of cells cultured on MMS without kinetin in the medium. In MMS without IAA and MMS without both IAA and kinetin, there was incorporation, but to a lesser extent in both the protein and the cell wall and/or cell membrane fractions. [ABSTRACT FROM AUTHOR]

Thermistor mounts are widely used for microwave power measurement, but suffer from drift caused by ambient temperature fluctuations. A Peltier oven has been developed which can be easily fitted to a thermistor mount to stabilize the mount temperature near the ambient temperature, thereby reducing the drift substantially. [ABSTRACT FROM AUTHOR]

Rapid detection of bacteria responsible for foodborne diseases is a growing necessity for public health. Reporter bacteriophages (phages) are robust biorecognition elements uniquely suited for the rapid and sensitive detection of bacterial species. The advantages of phages include their host specificity, ability to distinguish viable and non-viable cells, low cost, and ease of genetic engineering. Upon infection with reporter phages, target bacteria express reporter enzymes encoded within the phage genome. In this study, the T7 coliphage was genetically engineered to express the newly developed luceriferase, NanoLuc (NLuc), as an indicator of bacterial contamination. While several genetic approaches were employed to optimize reporter enzyme expression, the novel achievement of this work was the successful fusion of the NanoLuc reporter to a carbohydrate binding module (CBM) with specificity to crystalline cellulose. This novel chimeric reporter (nluc::cbm) bestows the specific and irreversible immobilization of NanoLuc onto a low-cost, widely available crystalline cellulosic substrate. We have shown the possibility of detecting the immobilized fusion protein in a filter plate which resulted from a single CFU of E. coli. We then demonstrated that microcrystalline cellulose can be used to concentrate the fusion reporter from 100 mL water samples allowing a limit of detection of ＜10 CFU mL−1E. coli in 3 hours. Therefore, we conclude that our phage-based detection assay displays significant aptitude as a proof-of-concept drinking water diagnostic assay for the low-cost, rapid and sensitive detection of E. coli. Additional improvements in the capture efficiency of the phage-based fusion reporter should allow a limit of detection of ＜10 CFU per 100 mL. [ABSTRACT FROM AUTHOR]