Development of lithium bromide-water absorption heat pump system for simultaneous production of heated-up air and steam from waste heat

Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.Absorption heat pumps (AHPs) operate by refrigeration techniques that use heat without requiring a compressor. In this study, an innovative AHP system is proposed that uses waste heat at 80 °C to produce hot air (at least 120 °C), which can be used for applications such as drying, and to simultaneously generate steam of 100–115 °C. Air is heated directly by heat exchange in the absorber working in the heating mode of a LiBr/H2O AHP system. Steam is then produced by heat exchange with the absorption solution, which is still at high temperature. The performance of a bench-scale AHP was evaluated by examination of running in a continuous mode. The tested AHP achieved a hot air temperature of more than 120 °C at the outlet of the absorber, and steam up to 115 °C was simultaneously generated by recovering heat from 80 °C hot water. The coefficient of performance, which is defined as the ratio of heat generated to the power consumed for pumping fluid, exceeded 20. The heat transfer rate in the absorber was dominated by an air stream through a bundle of tubes, but temperature in the evaporator was a significantly sensitive factor for the increasing temperature in this proposed AHP system.cf201

Integrated external cavity laser composed of spot-size converted LD and UV written grating in silica waveguides on Si

The authors report for the first time an external cavity laser composed of a spot-size converted LD and a UV written waveguide grating, both integrated on Si. The laser operates in a single mode with a side-mode suppression of 37 dB. The threshold current is 12 mA and the average thermal coefficient is as low as -1.7 GHz

Seasonal changes of arsenic speciation in lake waters in relation to eutrophication

金沢大学理工研究域物質化学系In this study, the influence of eutrophication on arsenic speciation in lake waters was investigated. Surface water samples (n = 1-10) were collected from 18 lakes in Japan during July 2007 and February 2008. The lakes were classified into mesotrophic (7 lakes) and eutrophic (11 lakes) based on the total phosphate (T-P) and chlorophyll-a (Chl-a) concentrations in water column. Inorganic, methylated and ultraviolet-labile fractions of arsenic species were determined by combining hydride generation atomic absorption spectrometry with ultraviolet irradiation. Organoarsenicals (mainly methylated and ultraviolet-labile fractions) comprised 30-60% of the total arsenic in most lakes during summer. On the other hand, inorganic arsenic species (As(III + V)) dominates (about 60-85%) during winter. The occurrence of ultraviolet-labile fractions of arsenic was higher in eutrophic lakes than those in mesotrophic lakes in both seasons. The concentration of dimethyl arsenic (DMAA) was high in eutrophic lakes during winter; and in mesotrophic lakes during summer. The results suggest that the conversion of As(III + V) to more complicated organoarsenicals occurred frequently in eutrophic lakes compared to that in mesotrophic lakes, which is thought to be the influence of biological activity in the water column. The distribution of arsenic species were well correlated with phosphate concentrations than those of Chl-a. This might be due to the competitive uptake of As(V) and phosphate by phytoplankton. The organoarsenicals (OrgAs)/As(V) ratio was higher at low phosphate concentration indicating that conversion of As(V) to OrgAs species was more active in phosphate-exhausted lakes with high phytoplankton density. © 2009 Elsevier B.V. All rights reserved

Seasonal changes of arsenic speciation in lake waters in relation to eutrophication.

金沢大学理工研究域物質化学系In this study, the influence of eutrophication on arsenic speciation in lake waters was investigated. Surface water samples (n=1-10) were collected from 18 lakes in Japan during July 2007 and February 2008. The lakes were classified into mesotrophic (7 lakes) and eutrophic (11 lakes) based on the total phosphate (T-P) and chlorophyll-a (Chl-a) concentrations in water column. Inorganic, methylated and ultraviolet-labile fractions of arsenic species were determined by combining hydride generation atomic absorption spectrometry with ultraviolet irradiation. Organoarsenicals (mainly methylated and ultraviolet-labile fractions) comprised 30-60% of the total arsenic in most lakes during summer. On the other hand, inorganic arsenic species (As(III+V)) dominates (about 60-85%) during winter. The occurrence of ultraviolet-labile fractions of arsenic was higher in eutrophic lakes than those in mesotrophic lakes in both seasons. The concentration of dimethyl arsenic (DMAA) was high in eutrophic lakes during winter; and in mesotrophic lakes during summer. The results suggest that the conversion of As(III+V) to more complicated organoarsenicals occurred frequently in eutrophic lakes compared to that in mesotrophic lakes, which is thought to be the influence of biological activity in the water column. The distribution of arsenic species were well correlated with phosphate concentrations than those of Chl-a. This might be due to the competitive uptake of As(V) and phosphate by phytoplankton. The organoarsenicals (OrgAs)/As(V) ratio was higher at low phosphate concentration indicating that conversion of As(V) to OrgAs species was more active in phosphate-exhausted lakes with high phytoplankton density

Tilt Angle and Theoretical Target Strength of the Japanese Sandeel, Ammodytes personatus Captured on the Northern Coast of Hokkaido, Japan.

The tilt angle, i.e., the angle from horizontal made by the fish body as its head dives down or up, affects the readings on fish echo soundings. We measured the tilt angle of Japanese sandeels (Ammodytes personatus Girard) in a water tank, and calculated the acoustic target strength (TS) using a theoretical scattering model. This study examined the TS of sandeels from the northern coast of Hokkaido, which have a larger body size than those in other regions in Japan. TS values for sandeels, a swimbladderless fish, were estimated using a distorted-wave Born approximation (DWBA) model at two frequencies: 38 and 120 kHz. The mean tilt angle was 20.4?? (S.D. = 18.5??), which differed slightly from that of the lesser sandeel, Ammodytes marinus. The regression equations of the average TS values were TS38kHz = 8.2 log10SL ??? 74.2 and TS120kHz = 20.9 log10SL ??? 92.6, respectively. At 120 kHz, the slope was close to 20, suggesting that the acoustic backscattering strength was proportional to the square of the body length. This value was smaller at 38 kHz, suggesting that the acoustic backscattering strength was stable to differences in body length. We obtained a small discrepancy for both frequencies (??TS = TS120kHz???TS38kHz) were TS120kHz < TS38kHz. Discrepancies of ???1.3 dB for the maximum TS, and ???1.8 dB for averaged TS were found in 72 fish samples, which would be useful for identifying sandeel schools in practical analysis using TS differences

Secretion of Streptomyces mobaraensis pro-transglutaminase by coryneform bacteria

We previously reported on the secretion of Streptomyces mobaraensis transglutaminase by Corynebacterium glutamicum ATCC13869 (formerly classified as Brevibacterium lactofermentum). In the present work, we investigated whether any other coryneform bacteria showed higher productivity than C. glutamicum ATCC13869. We found that most coryneform species secreted pro-transglutaminase efficiently. Moreover, we confirmed that Corynebacterium ammoniagenes ATCC6872 produced about 2.5 g/l pro-transglutaminase over a 71-h period in a jar fermentor. Our findings suggest that some other coryneform bacteria, especially C. ammoniagenes ATCC6872, are potential hosts for industrial scale protein production

Mechanosensory trichome cells evoke a mechanical stimuli–induced immune response in Arabidopsis thaliana

Perception of pathogen-derived ligands by corresponding host receptors is a pivotal strategy in eukaryotic innate immunity. In plants, this is complemented by circadian anticipation of infection timing, promoting basal resistance even in the absence of pathogen threat. Here, we report that trichomes, hair-like structures on the epidermis, directly sense external mechanical forces, including raindrops, to anticipate pathogen infections in Arabidopsis thaliana. Exposure of leaf surfaces to mechanical stimuli initiates the concentric propagation of intercellular calcium waves away from trichomes to induce defence-related genes. Propagating calcium waves enable effective immunity against pathogenic microbes through the CALMODULIN-BINDING TRANSCRIPTION ACTIVATOR 3 (CAMTA3) and mitogen-activated protein kinases. We propose an early layer of plant immunity in which trichomes function as mechanosensory cells that detect potential risks