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排序方式: 共有579条查询结果,搜索用时 31 毫秒
31.
Shuichi Yamamoto 《Drying Technology》2001,19(7):1479-1490
A simple method for determining concentration (water or solvent content) dependent diffusivity in liquid foods and polymer solutions from the regular regime drying curve was developed on the basis of the power-law diffusion model. The method was first tested to the drying data generated from numerical solutions of the diffusion equation with various types of concentration dependent diffusivities. The present method was found to be very simple yet accurate compared with the previous methods. Then, the drying rates of various sugar solutions experimentally obtained were analyzed on the basis of the present method to determine the moisture content dependent diffusivities. 相似文献
32.
Kyunghun Jung Yuta Yamamoto Shuichi Hasegawa 《Journal of Nuclear Science and Technology》2017,54(11):1261-1266
Excess micromotion of trapped calcium ions was detected and compensated in our linear Paul trap apparatus for trace isotope analysis. The micromotion was detected by Charge-coupled device (CCD). camera and radio frequency (rf) correlation method. We found that 230 and 2280 V of compensation voltages were needed for x- and y-axis compensation in our apparatus, respectively. The z-axis micromotion was confirmed by the experiment and its cause was investigated by finding a shape of z-axis confinement field. The confinement field was indeed distorted in our apparatus and it gave rise to the trapped ion to shift from potential center. And the micromotion of r-direction was transferred to the z-axis by the distorted confinement field. The z-axis micromotion was suppressed by increasing cap voltage of trap. 相似文献
33.
Annealing Effect in GaDyN on Optical and Magnetic Properties 总被引:1,自引:0,他引:1
Yi-Kai Zhou Masahiro Takahashi Shuichi Emura Shigehiko Hasegawa Hajime Asahi 《Journal of Superconductivity and Novel Magnetism》2010,23(1):103-105
The annealing effect on the optical and magnetic properties of the GaDyN layers was studied. The PL intensities of yellow
and green bands as well as the intra-4f orbital transition of Dy3+ ions were found to decrease for the samples annealed at 900 and 1000 °C. It is supposed that the intra-4f orbital transition is related to the broad peak luminescence coming from defects. Increasing the annealing temperature, the
magnetization becomes smaller. It is considerable that the number of electrons coming from defects was reduced by the annealing
treatments and that the ferromagnetism in GaDyN is attributed as carrier induced ferromagnetism. 相似文献
34.
Masanori Yoshida Akira Ito Kazuaki Yamagiwa Akira Ohkawa Masahiko Abe Shuichi Tezura Masuo Shimazaki 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2001,76(4):383-392
Power characteristics of an unbaffled aerated agitated vessel with unsteadily forward‐reverse rotating impellers, ie a new type of gas–liquid agitator named ‘AJITER’, treating viscous Newtonian liquids were studied experimentally. Measurements were first made on the agitation torque, ie the torque on the drive shaft on which forward–reverse rotating impellers with four delta‐type blades were attached, and the data obtained were analyzed by fitting them to an equation consisting of two terms with respect to the resistance of the fluid, one due to viscous drag and the other due to added moment of inertia. The effects of operating conditions and physical properties of liquids on the drag and added moment of inertia coefficients were then evaluated, and empirical relationships which estimate values of these coefficients, useful to predict the unsteady behavior and magnitude of agitation torque, were presented. Furthermore, equations were developed for estimating the average and maximum power consumptions as a function of the drag and added moment of inertia coefficients. Prediction of respective power levels in AJITER by these equations was also discussed. © 2001 Society of Chemical Industry 相似文献
35.
To improve the input-output coupling loss of a vertically coupled microring resonator filter, we fabricated microring resonators on an antiresonant reflecting optical waveguide (ARROW) with a large spot size and on the rectangular busline waveguide with a spot-size transformer. The spot size and the tapered structure were optimally designed from the viewpoint of spot-size matching to single-mode fibers and the reduction of radiation loss. Clear dropping responses were demonstrated for the ARROW-based microring resonator filters, and the coupling loss was successfully reduced by 22 dB. 相似文献
36.
Shuichi Kawamata Kiichi Okuda Takahiko Sasaki Ryozo Yoshizaki 《Journal of Low Temperature Physics》1999,117(3-4):891-895
The magnetic field direction dependence of the magnetic torque in the superconducting state of Bi
2
Sr
1.65
La
0.35
CuO
6+
(Bi2201) single crystal has been measured in several static magnetic fields up to 200 kOe. The applied field dependence of the anisotropy parameter, , defined by the square root of the effective mass ratio has been obtained by fitting the magnetic torque curves at 17 K by means of the effective mass model. For Bi
2
Sr
2
CaCu
2
O
8+
(Bi2212), the values up to 210 kOe were reported previously. At each field, for Bi2201 is larger than that for Bi2212. Since the value decreases as the field increases both for Bi2201 and Bi2212, the reduction of by the application of the high magnetic field is considered to be common for Bi-based layered superconductors. 相似文献
37.
Nitroxyl radicals are known to act as radical scavenging antioxidants. In the present study, a lipophilic nitroxyl radical,
cyclohexane-1-spiro-2′-(4′-oxyimidazolidine-1′-oxyl)-5′-spiro-1″-cyclohexane (nitroxyl radical I) was synthesized and its
antioxidant capacity was assessed in comparison with a hydrophilic nitroxyl radical, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl (Tempol). Both nitroxyl radical I and Tempol inhibited methyl linoleate oxidation induced by free radicals, and the
efficacy increased with decreasing partial pressure of oxygen, the effect being more pronounced for nitroxyl radical I than
Tempol. Their hydroxylamines inhibited lipid peroxidation more effectively than their corresponding parent nitroxyl radicals.
In liposomal membranes, a synergistic effect was observed in the combination of nitroxyl radical I with ascorbic acid, whereas
only an additive effect was observed between Tempol and ascorbic acid. The present study suggests that nitroxyl radical I
and its hydroxylamine may act as potent antioxidants, especially in combination with ascorbic acid under hypoxic conditions. 相似文献
38.
This paper describes a self-contained integrated microfluidic system that can separate motile sperm from small samples that are difficult to handle using conventional sperm-sorting techniques. The device isolates motile sperm from nonmotile sperm and other cellular debris, based on the ability of motile sperm to cross streamlines in a laminar fluid stream. The device is small, simple, and disposable yet is an integrated system complete with sample inlets, outlets, sorting channel, and a novel passively driven pumping system that provides a steady flow of liquid; it requires no external power source or controls. The device fulfills a need in clinical settings where small amounts of sperm need to be sorted. It also opens the way for convenient bioassays based on sperm motility including at-home motile sperm tests. 相似文献
39.
When a predatory mite, Amblyseius womersleyi is present, Tetranychus kanzawai takes refuge on its webs during a quiescent stage. To examine the factors responsible for the antipredator behavior of T. kanzawai, we exposed T. kanzawai to the odor of conspecifics, A. womersleyi, and both T. kanzawai and A. womersleyi. The proportion of T. kanzawai females that took refuge was significantly higher when they were exposed to the odor of `both T. kanzawai and A. womersleyi.' Furthermore, the proportion of T. kanzawai females that took refuge was significantly higher when they were exposed to injured conspecifics than to intact conspecifics. These results suggest that T. kanzawai assesses predation risk, at least in part, by using the odor of injured conspecifics. 相似文献
40.
Water-repellent surfaces were fabricated on blend sheets of poly(l-lactic acid)/poly(butylene succinate) with various blending ratios by the successive processing; (1) plasma etching, followed by (2) the hydrophobic plasma polymer coating. Rough morphology was formed effectively on the mosaic structured surface of blend sheets via the oxidative etching, and advanced water repellency was achieved after the thin membrane coating was synthesized with a hydrophobic plasma polymer coating by use of hexamethyldisiloxane or hexamethyldisilazane. High water repellency is expressed through the columnar hair-like structured model, where the air-water surface interaction in the voids is taken into account. 相似文献