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71.
Highly accurate thermodynamic property models for binary and ternary hydrocarbon mixtures containing propane, n-butane, and isobutane have been developed. In the present model, reliable equations of state explicit in Helmholtz free energy for these three hydrocarbons that have already been developed by the present authors have been adapted. The excess term used to represent the contribution of mixing was optimized for each binary mixture by using the available experimental thermodynamic property data including PTx, isochoric heat capacity, and saturation properties (bubble-point pressures, mole fractions in the vapor phase, and saturated vapor- and liquid-densities) as input data. A generalized correction for the three binary mixtures, besides the ideal mixing, consists of only four terms in its functional form, the structure of which was determined by simultaneous optimization to the input data for the three binary mixtures by employing a stepwise regression analysis. The bank of terms, that is a matrix of candidate terms applied for the regression, was carefully prepared through detailed observation of the nonideal mixing representation of the experimental data of the three binary mixtures. No additional adjustable parameters were used in the present model for the ternary propane/n-butane/isobutane mixture. Based on comparisons with the available experimental data and values from the developed equations of state, the present models for the three binary and the ternary hydrocarbon mixtures accurately represent most of the reliable experimental data. In addition, the graphical tests of the derived thermodynamic properties show that the models, including that for the ternary mixture, provide a physically sound representation of all the thermodynamic properties over the entire fluid phase.  相似文献   
72.
Synthesis of phytochelatins (PCs), heavy-metal-sequestering peptides, in the marine green alga, Dunaliella tertiolecta, was evaluated under various conditions of exposure to heavy metals. To investigate the effect of heavy metals on both PC synthesis and their upstream biosynthetic reactions, an ion-pair-HPLC system was developed in this study, by which PCs and their biosynthetic intermediates, cysteine (Cys), gamma-glutamylcysteine (gammaEC) and glutathione (GSH), could be determined simultaneously with high sensitivity. When the cells were exposed to Zn2+, the level of PCs was maximal at 200 microM and significantly higher than that obtained after exposure to 400 microM Cd2+, which is the strongest inducer of PC synthesis in higher plants in vivo and in vitro as well as in microalgae. The predominant PC subtype was PC4, followed by PC3 and PC5, whereas PC2, which is generally abundant in higher plants, has the lowest level among PC2 to PC5. These results suggest that the characteristics of PC synthase in D. tertiolecta including the requirement of heavy metals for its catalysis and substrate specificity towards GSH and PC(n) are considerably different from those in higher plants and other algae. While PC synthesis proceeded in the heavy-metal-treated cells, the level of GSH did not appreciably change. To maintain the same size of the GSH pool, GSH must be newly synthesized to balance the amount consumed for PC synthesis.  相似文献   
73.
The aim of this study is to develop an estimation method for a shape space. In this work, “shape space” means a nonlinear subspace formed by a class of visual shapes, in which the continuous change in shapes is naturally represented. By using the shape space, various operations dealing with shapes, such as identification, classification, recognition, and interpolation can be carried out in the shape space. This paper introduces an algorithm based on a generative model of shapes. A higher-rank of the self-organizing map (SOM2) is used to implement the shape space estimation method. We use this method to estimate the shape space of artificial contours. In addition, we present results from a simulation of omnidirectional camera images taken from mobile robots. Our technique accurately predicts changes in image properties as the robot’s attitude changes. Finally, we consider the addition of local features to our method. We show that the inclusion of local features solves the correspondence problem. These results suggest the potential of our technique in the future.  相似文献   
74.
Various ion-beam etching characteristics of diamond and selectivity between diamond and spin-on-glass (SOG) were examined. The maximum selectivity of diamond and SOG was 12.7 in oxygen reactive ion-beam etching process at 100 V acceleration voltage. Using this etching condition and dot-shaped SOG mask, conical diamond field electron emitter arrays with 30 nm curvature radius, 2.58 μm base radius and 5.86 μm height were fabricated.  相似文献   
75.
A rapid and sensitive method for detection of staphylococcal enterotoxin B (SEB) in raw and dry milk samples with the use of antibody-based immunomagnetic separation (IMS) in conjunction with flow cytometry (FCM) was developed. Sheep anti-SEB immunoglobulin G (IgG) was immobilized on Dynabeads M-280. The SEB initially binds to the capturing antibody, which is bound on the magnetic beads. The rabbit anti-SEB IgG binds to the captured toxin and is further labeled with a Cy5-labeled goat anti-rabbit IgG antibody. The percentage of the beads that were fluorescent was measured by FCM. FCM was carried out for 1 min, and the data obtained were expressed as histograms for particle size (forward light scatter) and histograms for fluorescence intensity. A peak corresponding to the magnetic beads was clearly distinguished from a peak derived from contaminating particles in the sample solution. In the absence of SEB, about 10% of the beads emitted fluorescence. The percentage of fluorescent beads and the fluorescence intensity increased with increasing SEB concentrations. For this IMS-FCM assay, the lower limits of detection for SEB were estimated to be 0.01 and 0.25 ng/ml for buffer and milk samples, respectively.  相似文献   
76.
Recently, the use of a ferromagnetic material in a soft‐heating method has garnered much attention as a novel method for cancer treatment. By concurrently using this material as a thermal probe, we are currently developing a minimally invasive heating and wireless temperature measurement system. To make the approach feasible in a clinical setting, it is vital to overcome the key challenge of heating the local tumor at a constant temperature. In previous conventional approaches, it was necessary to switch the induction‐heating power supply on/off after the target tumor temperature was reached. However, it cannot determine the temperature of the material during the power‐off period. Therefore, we changed this approach and found that by adjusting the distance between the heating coil and the material while maintaining a constant current flow in heating coil, the drift problem, which happened just after power is supplied during the on/off operation, did not occur any longer. Accordingly, it was not required to use multiple sensors to reduce the drift, thereby minimizing the cost. This study verifies the validity of our wireless thermometry approach while performing rotary scanning and proposes a technique for determining achievement of the target temperature. This knowledge complements other approaches for cancer treatment utilizing hyperthermia. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
77.
The principles of ion beam machining and its apparatus are described, and several examples are given of ultra fine forming or sharpening diamond tools by ion beams. Problems, such as a sub-micrometre tip radius or elliptical tips are discussed, and it is concluded that ion beam machining combined with mechanical pre-finishing can be useful for forming or sharpening diamond tools.  相似文献   
78.
79.
Studies were done on changes in phospholipid content and fatty acid composition of phospholipids and on the role of the acylation pathway in synthesis of phospholipids in the development of abnormal fatty acid composition in the glomeruli of rats 2 and 10 mo after induction of diabetes with streptozotocin. The proportions of individual phospholipids in the glomeruli of rats were not changed 2 mo after induction of diabetes, but the proportion of phosphatidylethanolamine (PE) decreased and that of sphingomyelin increased 10 mo after induction of diabetes. In contrast, in liver the proportion of PE was increased and that of phosphatidylcholine was decreased. These results showed that changes of individual phospholipids in glomeruli were time-dependent and tissue-specific. Two mo after induction of diabetes, the main change in the phospholipid fatty acid composition of diabetic glomeruli was a decrease in arachidonic acid (AA); the main change in serum free fatty acids (FFA) was an increase in linoleic acid (LA) and a decrease in AA. Ten mo after induction of diabetes, the main changes in the phospholipid fatty acid composition of glomeruli were an increase in LA and a decrease in AA; the main change of the serum FFA composition was a decrease in AA. Thus, the fatty acid composition of glomerular phospholipids was not directly correlated to that of the serum in diabetic rats. Acyl-CoA synthetase and acyltransferase activities increased in diabetic glomeruli with either AA or LA as substrate, but activity toward LA increased more at 2 mo after induction of diabetes. Acyl-CoA synthetase activity increased in diabetic glomeruli with LA as substrate, but that did not change with AA as substrate at 10 mo after induction of diabetes. Furthermore, acyltransferase activity decreased in diabetic glomeruli with AA as substrate, although that did not change with LA as substrate at 10 mo after induction of diabetes.  相似文献   
80.
A simple fabrication technology for delta-doped MOSFETs, named post-low-energy implanting selective epitaxy (PLISE) is presented. The PLISE technology needs no additional photo-lithography mask, deposition step or etching step even for CMOS devices. The only additional step is growing undoped epitaxial channel layers by UHV-CVD after the channel implantation. With this technology, delta-doped NMOSFETs with 0.1-μm gate length were successfully fabricated. By optimizing the epi-layer thickness and the channel doping level, short-channel effects are suppressed enough to achieve 0.1-μm gate length. Moreover, the junction capacitance at zero bias is reduced by 50%  相似文献   
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