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101.
La0.56−yLi0.33TiO3−3yF3y (y = 0.017, 0.05) were prepared by a conventional solid-state reaction from a mixture of La2O3, LiCO3, TiO2, and 10% excess LiF. The variation of the lattice parameter with increase of y value in La0.56−yLi0.33TiO3−3yF3y was different from that in conventional lithium-lanthanum-titanate series perovskite oxides, La0.56−yLi0.33+3yTiO3. Bulk Li-ion conductivities of the La0.56−yLi0.33TiO3−3yF3y are higher than those of La0.56-yLi0.33+3yTiO3. Li-ion conductivity of La0.56−yLi0.33TiO3−3yF3y (y = 0.017) was 2.30 × 10−3 S cm−1 at 30 °C, which is, to our knowledge, one of the highest Li-ion conductivities in the oxide compounds.  相似文献   
102.
Assembly errors can occur in a robotic assembly system. In this paper, a method that predicts an assembly error is proposed. It considers that assembly errors occur under the condition that the geometric trajectory of a mated part and the relational position and orientation of a base part are outside the allowable tolerance. A certain point, which is determined by using a physical light reflectance model of a mated part, is followed with two high-speed cameras. A statistical pattern recognition method in which explanatory variables are tracked points in a three-dimensional space is then employed to predict an assembly error. The proposed method is applied to a peg-in-a-hole assembly by a selective compliance assembly robot arm (SCARA)-type robot and its potential value is discussed.  相似文献   
103.
The flow characteristics of the centrifugal fans with different blade outlet angles are basically discussed on steady and unsteady simulations for a rectangular casing fan. The blade outlet angles of the impellers are 35° and 25° respectively. The unsteady flow behavior in the passage of the impeller 35° is quite different from that in the steady flow behavior. The large flow separation occurs in the steady flow field and unsteady flow field of the impeller 35°, the flow distribution in the circumferential direction varies remarkably and the flow separation on the blade occurs only at the back region of the fan; but the steady flow behavior in the impeller 25° is almost consistent with the unsteady flow behavior, the flow distribution of the circumferential direction doesn't vary much and the flow separation on the blade hardly occurs. When the circumferential variation of the flow in the impeller is large, the steady flow simulation is not coincident to the unsteady flow simulation.  相似文献   
104.
A new recording and readout technique for land and groove recording on a magnetic super-resolution (MSR) disk is described. The technique uses specifically premastered clock marks. To generate a stable clock signal, the clock marks are fabricated with short bursts in grooves by wobbling at a different frequency from address information. The clock marks and the address information can be separated from a track error signal. When the extracted clock signal is applied to precise recording and readout of the magneto-optical data marks, the bit error rate becomes lower than that of the conventional clock recording/readout system. Additionally, the crosstalk of the wobbled address information to the magneto-optical signal can be canceled out electronically. This new format is not only suitable for high-density recording but also convenient in the disk manufacturing process  相似文献   
105.
The strains generated in a reaction vessel of hydrogen storage alloys and the packing ratio distribution inside the vessel were measured in order to analyze the effects of packing on stress. More specifically strains generated on the vessel’s surface were measured when hydrogen is repeatedly absorbed and desorbed by the packed bed in the reaction vessel. The amount of deformation, local packing ratios and relative particle volumes in the vessel were also measured after repeated hydrogen absorption–desorption. As absorption–desorption was performed repeatedly, agglomeration regions where the value of the local packing ratio was around 0.6 were formed, and particularly strong stress was generated in these regions, causing deformation. More hydrogen packing causes agglomeration regions to form over a wider area. Since alloys are pulverized by repeated absorption–desorption, and concentrate in the lower parts of the vessel, agglomeration regions are also formed in the lower parts. Our experiments also revealed that the resulting agglomeration regions have a packing ratio of about 0.6.  相似文献   
106.
Aggregates of amyloid-β (Aβ) peptides are known to be related to Alzheimer’s disease. Their aggregation is enhanced at hydrophilic–hydrophobic interfaces, such as a cell membrane surface and air-water interface, and is inhibited by polyphenols, such as myricetin and rosmarinic acid. We review molecular dynamics (MD) simulation approaches of a full-length Aβ peptide, Aβ40, and Aβ(16–22) fragments in these environments. Since these peptides have both hydrophilic and hydrophobic amino acid residues, they tend to exist at the interfaces. The high concentration of the peptides accelerates the aggregation there. In addition, Aβ40 forms a β-hairpin structure, and this structure accelerates the aggregation. We also describe the inhibition mechanism of the Aβ(16–22) aggregation by polyphenols. The aggregation of Aβ(16–22) fragments is caused mainly by the electrostatic attraction between charged amino acid residues known as Lys16 and Glu22. Since polyphenols form hydrogen bonds between their hydroxy and carboxyl groups and these charged amino acid residues, they inhibit the aggregation.  相似文献   
107.
Complicated and sophisticated protein homeostasis (proteostasis) networks in the endoplasmic reticulum (ER), comprising disulfide catalysts, molecular chaperones, and their regulators, help to maintain cell viability. Newly synthesized proteins inserted into the ER need to fold and assemble into unique native structures to fulfill their physiological functions, and this is assisted by protein disulfide isomerase (PDI) family. Herein, we focus on recent advances in understanding the detailed mechanisms of PDI family members as guides for client folding and assembly to ensure the efficient production of secretory proteins.  相似文献   
108.
109.
Track-edge noise has been analyzed to clarify track-edge noise mechanisms. Edge noise arises from two different regions: the bit edge where the magnetization direction is opposite to the previously dc-erased direction and the magnetic transition edge. The edge noise at low density is mainly due to the magnetic distribution at the bit edge. The transition edge noise increases with increasing recording density, and it becomes dominant at high-recording density for an oriented medium. On the other hand, the transition edge noise is almost constant with increasing recording density for an isotropic medium  相似文献   
110.
Aluminium hydroxide (Al(OH)3) was mechanically activated by dry milling. In order to develop an inorganic consolidated material, the structure and reactivity of milled Al(OH)3 were investigated and consolidated bodies were prepared using the reaction between activated Al(OH)3 and a potassium silicate solution. Milling up to 1 h apparently reduced the grain size and promoted amorphization, although milling longer than 2 h did not give a significant physical change. Milled Al(OH)3 directly transformed to -Al2O3 around 270°C. The transformation temperature decreased with increasing milling time. The remarkable enhancement of the reactivity was attained. The reactivity of Al(OH)3 milled for 2 h improved 1000 times more than that of as-received Al(OH)3. The preforming paste, prepared with as-received Al(OH)3, could not consolidate at room temperature without drying. On the other hand, for Al(OH)3 milled for 2 h, the preforming paste consolidated in 10 min and the consolidated material showed much better resistance against water than that prepared with as-received Al(OH)3. The possibility of a new inorganic consolidated material was suggested using the reaction between mechanically activated Al(OH)3 and the potassium silicate solution.  相似文献   
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