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1.
Static and fatigue shear tests of steel–Ni bonds and steel–Ti bonds were carried out to obtain the relations between the strengths
and the bonding conditions. Ultrasonic measurements were also made to examine the relations between the strengths and the
size of the bonded region (the estimated diameter). At the bonding interface of the steel–Ni bonds, no intermediate phase
was observed. At the bonding interface of the steel–Ti bonds, a thin layer of intermetallic compound was formed at lower bonding
temperatures but, at higher bonding temperatures, the interlayer melted and the bonding interface became rough. The intensity
of the ultrasonic wave reflected from the bonding interface changed, depending on the state of the bonding interface. In shear
tests of the steel–Ni and steel–Ti bonds, cracks propagated along the bonding interface, and the strength was proportional
to the square of the estimated diameter. In fatigue tests, cracks propagated in the thickness direction of the plate and no
relation was obtained between the fatigue life and the estimated diameter. Fatigue life distributions were represented by
two- and three-parameter Weibull distributions.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
2.
The role of water vapor in crystallite growth and the tetragonal-to-monoclinic phase transformation of ZrO2 was studied using three specially prepared samples: an ultrafine powder of monoclinic ZrO2 obtained by hydrolysis of ZrOCI2 , an aggregated powder of tetragonal ZrO2 obtained by thermal decomposition of Zr(OH)4 under reduced pressure, and an ultrafine powder of tetragonal ZrO2 obtained by thermal decomposition of zirconyl acetate dispersed in caramel. The samples were heat-treated up to 1000°C in dry and wet atmospheres saturated with water vapor at 90°C. It was found that water vapor markedly accelerated crystallite growth for both monoclinic and tetragonal ZrO2 and facilitated the tetragonal-to-monoclinic phase transformation. Water vapor increases surface diffusion and thus enhances crystallite growth and decreases surface energy, which leads to stabilization of the tetragonal phase. 相似文献
3.
SUMMARY– The formation of N -substituted pyrrole-2-aldehydes in the browning reaction between D-xylose and selected amino acids was investigated.
In order to facilitate the separation of the reaction products, the carbonyl compounds formed in the browning solution were converted into 2,4-dinitrophenylhydrazones (2,4-DNPs) and then esterified with diazomethane. Isolation of the esterified 2,4-DNP was accomplished by column chromatography with alumina. Chemical structures of the isolated 2,4-DNPs were confirmed by elementary analyses, ultraviolet and visible absorption spectra, and nuclear magnetic resonance spectra.
The following N -substituted pyrrole-2-aldehydes were isolated as methyl ester of 2,4-DNP, respectively: (2-formylpyrrol-I-ybacetic acid from the reaction mixture of D-xylose and glycine, 3-(2-formylpyrrol-1-y1)propionic acid from β-alanine, and 2-(2-formylpyrrol-1-y1)-4-methyl-valeric acid from L-leucine.
The extent of pyrrolealdehyde formation from D-xylose and selected alkylamine or amino acid was in the following order which corresponded to the extent of melanoidin formation: n-butylamine > methylamine, β-alanine > glycine > DL-alanine. N-substituted pyrrole-2-aldehyde was rather stable and was not considered to be an important intermediate of melanoidins. However, some correlationships between the formation of pyrrolealdehyde and that of melanoidins were demonstrated and discussed. 相似文献
In order to facilitate the separation of the reaction products, the carbonyl compounds formed in the browning solution were converted into 2,4-dinitrophenylhydrazones (2,4-DNPs) and then esterified with diazomethane. Isolation of the esterified 2,4-DNP was accomplished by column chromatography with alumina. Chemical structures of the isolated 2,4-DNPs were confirmed by elementary analyses, ultraviolet and visible absorption spectra, and nuclear magnetic resonance spectra.
The following N -substituted pyrrole-2-aldehydes were isolated as methyl ester of 2,4-DNP, respectively: (2-formylpyrrol-I-ybacetic acid from the reaction mixture of D-xylose and glycine, 3-(2-formylpyrrol-1-y1)propionic acid from β-alanine, and 2-(2-formylpyrrol-1-y1)-4-methyl-valeric acid from L-leucine.
The extent of pyrrolealdehyde formation from D-xylose and selected alkylamine or amino acid was in the following order which corresponded to the extent of melanoidin formation: n-butylamine > methylamine, β-alanine > glycine > DL-alanine. N-substituted pyrrole-2-aldehyde was rather stable and was not considered to be an important intermediate of melanoidins. However, some correlationships between the formation of pyrrolealdehyde and that of melanoidins were demonstrated and discussed. 相似文献
4.
AKIO MAKEHIMA YOSHIAKI TAMURA TERUO SAKAINO 《Journal of the American Ceramic Society》1978,61(5-6):247-249
Glasses in the system Al2 O3 -Y2 O3 -SiO2 , containing TiO2 and La2 O3 , were investigated. Glasses of high refractive index and elastic modulus were developed. The observed Young's and shear moduli of these glasses show good agreement with theoretical values. Agreement was also found between the observed and calculated values of refractive index when the Appen's empirical coefficients were used. 相似文献
5.
Two special types of anhydrous aluminum sulfate with extreme grain shapes were prepared; one, obtained by precipitation from concentrated sulfuric acid solution, is rhombohedral near cubic single-crystal grains and the other, from acetic acid solution, consists of very thin flaky particles. The morphology of sulfate and calcined alumina, the sulfate decomposition, the η-α alumina transformation, and the crystallite growth of α alumina were studied and compared with those processes for reagent-grade sulfate. The morphology of anhydrous sulfate was shown to greatly affect the heat-treatment characteristics of alumina and the sulfate decomposition behavior. 相似文献
6.
Water-soluble polymers were degraded by ozone, and the degradation rate defined by the change of weight average polymerization degree per unit time was obtained. The degradation rate of poly(oxyethylene) (PEG) was proportional to the 1.5 to 2.0 power of the polymerization degree, and was 20 to 60 times that of poly(acrylamide) (PAAm). The experimental results of PEG and PAAm were correlated as a function of polymerization degree, temperature, dissolved ozone concentration and OH? ion concentration. The degradation rate of poly(sodium acrylate)(PANa) was proportional to the 2.0 power of the polymerization degree when no other electrolyte was added. However, the degradation rate of PANa decreased with the increase in NaCl concentration, and approached that of PAAm in the range of high NaCl concentrations. 相似文献
7.
Emulsion Stabilization by Maillard-type Covalent Complex of Plasma Protein with Galactomannan 总被引:7,自引:0,他引:7
NAOTOSHI MATSUDOMI YURIKA INOUE HISASHI NAKASHIMA AKIO KATO KUNIHIKO KOBAYASHI 《Journal of food science》1995,60(2):265-268
Plasma protein was conjugated with galactomannan (GM) in a controlled dry state at 60°C and 79% relative humidity. The covalent attachment of GM to plasma protein was confirmed by SDS-PAGE and gel chromatography. Emulsifying activity of plasma protein-GM complex was 1.4 times and the emulsion stability of the complex was more than 10 times higher than those of plasma protein. In acidic (pH 3) and salt (0.2M NaCl) systems, the complex showed much more effective emulsifying properties than did commercial emulsifiers. Emulsifying properties of the complex were retained after preheating at 80°C for 30 min. Plasma protein-GM complex prepared by Maillard reaction during heating in a dry state could be used for heat-processed foods as a protein emulsifier. 相似文献
8.
Ovalbumin freeze-dried with or without the addition of glucose was stored at 50°C and 65% relative humidity to study the effect of the Maillard reaction on some physical properties of ovalbumin. In the early stage of the reaction in which ovalbumin-glucose complexes were formed, there were soluble types of monomer and aggregates of which α-helix and available lysine contents were gradually decreased with length of storage and degree of aggregation. These compounds were characterized by properties possessing a marked resistance towards destruction of conformation and coagulation. With progress of the reaction, ovalbumin-glucose complexes changed to insoluble forms having higher particle weight and breakdown products. 相似文献
9.
Diagnosis Criterion of Abnormality of Transformer Winding by Frequency Response Analysis (FRA) 下载免费PDF全文
SATORU MIYAZAKI YOSHINOBU MIZUTANI AKIRA TAGUCHI JUNICHI MURAKAMI NAOKAZU TSUJI MASAHIRO TAKASHIMA OSAMU KATO 《Electrical Engineering in Japan》2017,201(3):25-34
Frequency response analysis (FRA) is a powerful technique to detect internal abnormalities within power transformers. However, diagnosis criteria of power transformers by FRA have not been fully established yet. In this paper, a new evaluation method of degree of identification between two transfer functions is proposed. In the proposed method, a frequency window is employed and cross‐correlation factor is calculated with moving the window. Furthermore, the proposed method is applied to transfer functions of real transformers with or without some abnormalities. Based on this discussion, objective criteria for diagnosis of abnormalities of transformer windings by FRA are proposed. The proposed criteria are based on a few data of transformers with some abnormalities. Therefore, the proposed criteria are tentative and they would be improved by accumulation of further data. 相似文献
10.
KOJI AIZAWA SOTA KOBAYASHI HIROSHI ISHIWARA KAZUYUKI SUZUKI KAZUMI KATO 《Integrated ferroelectrics》2013,141(1):169-174
Fabrication and characterization of metal-ferroelectric-insulator-semiconductor field-effect-transistors (MFIS FETs) using (Y,Yb)MnO3/Y2O3/Si structures were introduced for the first time. P-channel MFIS FETs were fabricated on n-type Si(111) substrates, in which an Y0.5Yb0.5MnO3(200 nm)/Y2O3(25 nm) structure was used as gate insulator. The Y0.5Yb0.5MnO3 and Y2O3 films were prepared by chemical solution deposition. A fabricated MFIS FETs showed the hysteresis loop due to spontaneous polarization in the ID-VGS characteristic, in which the memory window was about 0.9V when the applied gate voltage was swept between 8 V and ?8 V. Especially, the alternative drain current was retained after applying a single voltage pulse with a magnitude of +9 V or ?9 V. 相似文献