The use of a surface developer, pyrocatechol, to process transmission electron microscope negatives has been shown to have significant advantages over the conventional D-19 process. The process described here is tolerant of a large margin of error in the electron exposure and produces a negative that not only retains details both in the highlight as well as the faint regions, but also preserves local contrast. These characteristics are particularly useful in convergent beam electron diffraction applications where one encounters a wide contrast range. Improved acuteness and an enhanced signal to noise ratio due to the prolonged exposures associated with this process have also been observed. 相似文献
A hybrid system consisting of vapour compression unit, a liquid desiccant system, and a flat solar hot water collector were designed, fabricated and tested. This combination allowed for a separate control of humidity and temperature without energy penalty. Various packing heights of the absorber component were tested to determine the optimal performance of the combined unit. A 1000 mm packing height with cross-sectional area of 600×600 mm, proved to be the best height that gives promising improvements in the coefficient of performance of the vapour compression unit. 相似文献
Valve trays are becoming popular in the chemical process industries owing to their flexibility to handle a wide range of vapor
throughputs. Using the rigorous rate based model, the importance of the non-equilibrium approach is demonstrated for a typical
extractive distillation process in a Glitsch V-1 valve tray column. Simulation results based on an in-house developed code
indicated that the rate based model predictions for a valve tray column operation showed significant differences relative
to the equilibrium model. Even small errors in product purities translated into nonoptimal feed stage locations and inaccurate
number of stages required. The counter-intuitive effect of high reflux ratio on separation is explained. 相似文献
Water and microbial contamination is a serious issues to aquatic system and human health. The metal selenide has a tremendous technique to degrade the dyes and bacteria.The present work reports the synthesis of ZnSe nanoparticles in a simple co-precipitation method. The synthesized samples were analyzed by structural, optical, morphological, catalytic and biological activity. The size and bandgap by annealing temperature tuning which are confirm by X-ray Diffraction and UV–Visible spectrometer. The quasi-spherical shapes were confirmed by Scanning Electron Microscope and Transmission Electron Microscope.The photo excited electrons have trapped the metals and promoting the degradation system. The release of ions to the surface was acknowledged by Photo Luminescence spectroscopy. The photocatalytic dye degradation of the Methyl Orange showed that the enhanced activity in high temperature. The photocatalytic dye degradation activity suggested that the temperature change the production of free radicals and ROS formation. The hydroxyl radicals were slewing the dye molecules and bacteria. The obtained results giving the information of ZnSe nanoparticles are one of the fascinating research areas in the current research world. Because of its large application in different field it acts as a promoting catalytic and biological application.
Phosphatidic acid (PtdOH) and lysophosphatidic acid (lysoPtdOH) have been shown to enhance T-lymphocyte function. However,
the FA preference and influence of acyl-CoA binding proteins on lysoPtdOH and PtdOH biosynthesis are not known. Therefore,
we determined glycerol-3-phosphate acyltransferase (GPAT) and lysophosphatidic acid acyltransferase (LAT) activity in rat
T-lymphocyte and liver membrane preparations in the presence of palmitoyl-CoA and oleoyl-CoA with or without BSA. We found
two different properties of GPAT and LAT in whole T-lymphocyte membrane preparations relative to liver. First, T-lymphocyte
basal GPAT and LAT activities were similar, whereas in liver membranes LAT activity was 10-fold higher than GPAT. Second,
T-lymphocyte LAT, but not GPAT, activity was inducible (fivefold) by the addition of albumin in the presence of palmitoyl-CoA
but not oleoyl-CoA. In contrast, albumin stimulated GPAT, but not LAT, activity in liver membranes in the presence of palmitoyl-CoA.
These results show, for the first time, that T-lymphocyte LAT activity can be increased by the presence of an acyl-CoA binding
protein, which may indicate a new important control mechanism for regulating intracellular lysoPtdOH and PtdOH levels in T-lymphocytes. 相似文献
An air-water experimental system consisting of two inlets and one outlet is constructed and characterised. It reaches the state of sliding mode, or equivalently, two phase slug flow. The linear hydraulic model proposed in the literature is adequate to describe it. Experimental data are used to tune this model. The resistance to the flow of air through the outlet valve during the two phase flow is much larger than that when air alone flows out. At the operating range, the resistance to water flow is not affected by the presence of air. 相似文献