Development of 28?GHz and 77?GHz, Mega-Watt Gyrotrons for Fusion Devices

A 28 GHz 1 MW with TE_8,3 cavity for GAMMA10 tandem mirror and a 77 GHz 1.5 MW gyrotron with TE_18,6 for Large Helical Device (LHD) have been developed to upgrade their Electron Cyclotron Heating (ECH) systems. In the 28 GHz gyrotron, the maximum power of 1.05 MW was obtained, which is in agreement with its design target value. And the high efficiency of 40% without collector potential depression (CPD) was obtained with 0.8 MW. In the first and second 77 GHz gyrotrons, 0.8 MW 3.6 sec., 0.3 MW 60 sec operations have been achieved, but several issues due to the stray RF and velocity dispersion have been found, too. In consideration of these, the design improvement was performed to aim at 1.5 MW in the third tube. In the short pulse test, the maximum output power of 1.6 MW and the maximum total efficiency of 49.4% with CPD were obtained. In the long pulse test, the pulse length extended to 5 sec with 1 MW, 1800 sec with 0.1 MW, 1.6 sec with 1.5 MW. Total injection power of 3.1 MW to LHD plasma has been achieved. It is shown that the electron beam pitch factor ?? decreases with increasing of beam current, comparing with the experimental and calculation results.     

Production of indigenous alcoholic beverages in a rural village of Cameroon

In this study, the indigenous alcoholic beverages in a rural village of Cameroon were investigated. The technique for producing alcoholic beverages in the village was observed, and the concentrations of ethanol, glucose and lactic acid and the pH values during the course of production were measured using portable devices at the field site. Eight different kinds of alcoholic beverage (palm wine, palm spirits, raffia wine, cassava spirits, maize turbid beer, maize spirits, plantain wine and plantain spirits) were produced and consumed in the village. Of these beverages, palm wine, made from palm sap, was the most important alcoholic beverage in a villager's daily life. In addition, starch‐based alcoholic beverages were distilled rather than drunk directly. As germinated maize, which has a relatively low amylase activity, was used as an amylase source in production, starch‐based alcoholic beverages might need to be distilled to enhance the ethanol concentration. During the course of production, the pH was reduced using local techniques, which proved to be effective in preventing bacterial contamination. Copyright © 2014 The Institute of Brewing & Distilling     

Performance of a polymer electrolyte fuel cell for automotive applications

The objectives of this study were to fabricate a self‐humidifying fuel cell stack of 10 cells with 104 cm² cell areas humidified with water recovered at cathodes, and to measure and simulate the performance of the stack. This involves the simulation of a three‐dimensional model of the heat and mass transfer of the water and the gaseous reactants in the fuel cell components with a water‐cooling system. The results of the stack experiments indicated a maximum power of 250 kW at a current density of 0.5 A/cm². The simulation showed good agreement with the actual performance of the stack. The performance of the self‐humidifying stack with a vapor‐permeating membrane is comparable to a conventional stack with external humidifiers, and it appears very effective in simplifying stack systems. The modeling analysis indicated that for the gas flow directions, at anode and cathode, a parallel flow is superior to a cross flow, and that one cooling cell is necessary for two to three generating cells in order to maintain the fuel cell temperature below 100 °C. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(6): 421–429, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10041     

Use of a novel microfluidic disk in the analysis of single-cell viability and the application to Jurkat cells

Jurkat cells were trapped in the microchambers of a novel disk-shaped cell separation device and stained with Cellstain. Approximately 90% of the cells were living. Single cells were isolated with a branching microchannel after rotation at 4500rpm for 30s, demonstrating that a living single cell could be trapped in the microchambers.     

Sperm acrosin is responsible for the sperm binding to the egg envelope during fertilization in Japanese quail (Coturnix japonica)

An antibody library against quail sperm plasma membrane components was established and a mAb, which strongly inhibits sperm perforations of the perivitelline membrane (PVM) was obtained from the library. The antigen molecule of the mAb showed an apparent molecular weight of 45 kDa, and was distributed both on the surface and in the acrosomal matrix of the sperm head. Periodate oxidation revealed that the epitope of the antigen includes a sugar moiety. Tandem mass spectrometry analysis of the antigen revealed that the mAb recognizes sperm acrosin. When sodium dodecyl sulfate-solubilized PVM immobilized on a polyvinylidene difluoride membrane was incubated with sperm plasma membrane lysates, the sperm acrosin was detected on the PVM immobilized on the membrane, indicating that the sperm acrosin interacts with the components of PVM. Indeed, the mAb effectively inhibited the binding of acrosome-intact sperm to the PVM. These results indicate that the 45 kDa sperm acrosin is involved in the binding of sperm to the PVM in fertilization of Japanese quail.     

Numerical Simulation of Water Flow through Nano-Hydraulic Turbine Driven by Rapid and Shallow Stream

This study is concerned with the numerical simulation of the flow through an open type cross-flow runner of a nano-hydraulic turbine driven by rapid and shallow stream. It employs the two-dimensional particle method, which was used for the flow simulation of a small-scale hydraulic turbine of impulse-type in the prior study. The tip speed ratio 2, defined as the ratio of the runner tip speed to the water stream velocity upstream of the runner, ranges from 0.1 to 0.8. The simulated flow at 2 = 0.5 is confirmed to agree well with the experimentally visualized one. The effect of 2 on the flows inside the rotating cascade as well as around the runner is clarified. The turbine performance, calculated by using the simulated flow, is also highlighted to agree almost with the measurement. These demonstrate that the present simulation method is indeed applicable to the development of open type cross-flow runner of nano-hydraulic turbine utilizing rapid and shallow stream.     

Isopropylation of naphthalene over H-mordenite,H-Y,and H-beta zeolites: Roles of isopropylnaphthalene isomers

Isopropylation of naphthalene (NP) was examined over H-mordenite (MOR), H-Y zeolite (FAU), and HBeta zeolite (BEA) in order to elucidate roles of isopropylnaphthalene (IPN) isomers during the catalysis. 2-IPN was the predominant isomer over MOR and works as a precursor for the selective formation of β,β-DIPN, particularly, 2,6-DIPN. In contrast, 1-IPN was predominant (with 2-IPN as a minor isomer) over FAU and BEA at low temperatures; dialkylation accompanied by the consumption of 1- and 2-IPN led to predominant formation of α,α- and α,β-DIPN. The formation of β,β-DIPN from 2-IPN was enhanced at higher temperatures. Bulky transition states of 1-IPN in IPN isomers and α,α- and α,β-DIPN among DIPN isomers were hindered by the interaction with MOR channels, resulting in the selective formation of β,β-DIPN, particularly 2,6-DIPN through the less bulky 2-IPN. FAU and BEA allow the formation of α,α- and α,β-DIPN from both of 1- and 2-IPN isomers because their channels are too large to exclude bulky transition states. The catalysis over FAU and BEA occurred under kinetic control at lower temperatures, and thermodynamic control also participates at higher temperatures.     

Interference effects on local peak pressures between two buildings

Local peak pressure coefficients between two buildings were studied by using wind tunnel experiments for various locations, different height ratios of interfering building and wind directions. The measured local peak pressure coefficients were compared to those obtained previously from a study on an isolated building. This study also investigated interference effects for local peak pressures on a principal building with various configurations and different height ratios of an interfering building. The experimental results have been examined and presented from the viewpoint of cladding design. The results show that highest peak suctions on a principal building increased with increase in height ratios of the interfering building. The oblique configuration generated more severe peak suction than the tandem configuration. To examine the interference effects for local peak pressures in detail, interference factors for maximum positive and minimum negative peak pressures at each measurement point (i, j) of the principal building for all wind directions are presented and discussed.     

几种非平稳分析方法对非平稳风力时程的比较分析

非平稳信号的分析方法是信号分析领域中的一个重要问题。本文以风洞试验获得的非平稳风压信号和升力系数信号为研究对象,分别采用短时傅里叶变换、Wigner-Ville分布,小波变换方法和Hilbert-Huang变换(HHT)方法对信号进行时频分析。分析结果表明,由于短时傅里叶变换、Wigner-Ville分布,小波变换方法都是基于傅里叶变换,因此,得到的频谱特性都大致相同,只是在分析的精细程度上有所差异;HHT方法可以获得有意义的瞬时频率,从而给出频率随时间变化的精确表达,信号最终被表示为时频平面上的能量分布,成为Hilbert谱,该方法适用于分析生活中普遍存在的大量频率随时间变化的非线性、非平稳信号,可将复杂的信号直接分离成从高频到低频的若干阶固有模态函数。另一方面,无论用哪一种分析方法都可以看出,风速和风压信号的能量大多分布在低频部分,高频部分所占比例很少,而升力信号的能量大多分布在高频部分,低频部分所占比例很少。本文采用HHT方法提取起控制作用的信号主成分。     

Changes in immunoelectron microscopic localization of cathepsin D in muscle induced by conditioning or high-pressure treatment

Changes in the localization of cathepsin D in postmortem and pressurized rabbit muscles were investigated by immunoelectron microscopy. The anti-cathepsin D monoclonal antibody strongly labeled a large vesicle in a subsarcolemmal part of the cell , which strongly suggests that this is the primary lysosome. The liberation of the cathepsin D entrapped in the lysosomes in the muscle prepared immediately after death proceeded with the progress of the conditioning. The release of almost all cathepsin D from the lysosomes and its absorption on the myofibrils were observed in the muscle conditioned for 14 days. The accumulation of lysosomes having various volumes and shapes accompanied with the disruption of myofibrillar structure was also observed. The liberation of cathepsin D from the lysosomes can be attributed to the modification of membranes permeability of the lysosomes during conditioning. When the muscle was pressurized at 100 MPa, the modification of the round shape of the lysosome was observed. With the increase of the pressure applied to the muscle, the release of cathepsin D from the lysosome due to the disruption of membrane was accelerated, and absorption of the released cathepsin D on the myofibrils was observed. From the results obtained, it was clear that the changes in the localization of cathepsin D accompanied with the modification of lysosomes induced by the brief exposure to high pressure were drastic in comparison with that in the muscle during conditioning.