309 research outputs found

    Structural Diagrams and Phase Reactions of the Quaternary 12%Cr-Fe-C-N System

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    The isothermal diagrams of the 12% Cr-Fe-C-N system in the composition range up to 0.4% carbon and 0.3% nitrogen were studied at temperatures from 1300℃ to 700℃. Resorting to the consideration of phase relationship, the phase reaction of 12%Cr-Fe-C-N system was clarified and the sectional diagrams were constructed at fixed contents of 0.1% and 0.2% nitrogen and carbon, respectively. In Fe-Cr-C-N system, the quaternary peritecto-eutectoid reaction (chemical formula) exists at about 780℃, representing by the hexahedron of five-phase region consisting of α, γ, Cr_C_6, Cr_7C_3 and Cr_2N. The Cr_7C_3 type carbide detected in the present work is expressed by the formula (Fe_2C_5)C_N_

    Solubility of Nitrogen in Austenitic Iron under High Nitrogen Pressure and Thermodynamic Properties of Iron-Nitrogen Interstitial Solid Solution

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    Studies on the equilibrium between austenitic iron and nitrogen under various conditions of the maximum pressure of 920 kg/cm^2 and the temperature range from 950°to 1300℃ were carried out by using a high temperature and high pressure equipment. It was shown that the concentration of nitrogen in austenite deviated from Sieverts\u27 law with increasing pressure. The casue for such discrepancy was considered thermodynamically and statistically. That is, the experimental result can reasonably be explained from the geometrical consideration that the chemical potential of a nitrogen atom in austenite, in case of a high nitrogen content deviates remarkably from that in an idial random interstitial solid solution, since each intestitial atom added excludes other interstitial atoms from the seven adjacent sites. Thus, the activity of nitrogen in austenitic iron can be expressed by the following equations : log a_N=log N_N/1-9N_N+ 3.34-427/T for the standard state of nitrogen gas 1 atm pressure, a_N=f^_ log a_N=log N_N/1-9N_N for the standard state of infinitely dilute solid solution

    Constitutional Diagrams of Iron-Rich Corner in 18% Cr-Fe-C-N System

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    The constitutional diagrams of 18%Cr-Fe-C-N quaternary system were examined up to 0.5% of both carbon and nitrogen in the temperature range of 1300°to 700℃, and the sectional diagrams were described at fixed contents of 0.1 and 0.2% nitrogen, and 0.1, 0.2 and 0.3% carbon. In the present range of composition, ferrite and austenite existed in equilibrium in the range of 1300°to 1100℃, and the austenite-promoting effects of carbon and nitrogen were very nearly equivalent and additive. The minimum concentration of carbon plus nitrogen required to obtain a completely austenitic structure was about 0.4%. Below 1100℃, Cr_C_6, Cr_7C_3 and Cr_2N precipitated and the phase regions recognized were γ+Cr_C_6, γ+Cr_7C_3, γ+Cr_2N, γ+Cr_C_6+Cr_2N, α+γ+Cr_C_6, α+γ+Cr_2N, α+γ+Cr_C_6+Cr_2N, α+Cr_C_6+Cr_2N, α+Cr_C_6 and α+Cr_2N. It was presumed that the four-phase region of α+γ+Cr_C_6+Cr_2N arose from the eutectoid reaction γ→α+Cr_C_6+Cr_2N. The compositions of Cr_C_6 and Cr_2N were generally represented by (Fe_7Cr_)C_6 and (Fe_Cr_)C_N_, respectively

    Relationship between cognitive function and prevalence of decrease in intrinsic academic motivation in adolescents

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    <p>Abstract</p> <p>Background</p> <p>Decrease in intrinsic motivation is a common complaint among elementary and junior high school students, and is related to poor academic performance. Since grade-dependent development of cognitive functions also influences academic performance by these students, we examined whether cognitive functions are related to the prevalence of decrease in intrinsic academic motivation.</p> <p>Methods</p> <p>The study group consisted of 134 elementary school students from 4th to 6th grades and 133 junior high school students from 7th to 9th grades. Participants completed a questionnaire on intrinsic academic motivation. They also performed paper-and-pencil and computerized cognitive tests to measure abilities in motor processing, spatial construction, semantic fluency, immediate memory, short-term memory, delayed memory, spatial working memory, and selective, alternative, and divided attention.</p> <p>Results</p> <p>In multivariate logistic regression analyses adjusted for grade and gender, scores of none of the cognitive tests were correlated with the prevalence of decrease in intrinsic academic motivation in elementary school students. However, low digit span forward test score and score for comprehension of the story in the <it>kana </it>pick-out test were positively correlated with the prevalence of decrease in intrinsic academic motivation in junior high school students.</p> <p>Conclusions</p> <p>The present findings suggest that decrease in capacity for verbal memory is associated with the prevalence of decrease in intrinsic academic motivation among junior high school students.</p

    非線形光ファイバカプラによるフェムト秒パルスの全光スイッチング及び結合特性

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    We analyze numerically the propagation of ultra-short optical pulses in a nonlinear fiber directional coupler by taking into account the dispersion effect of the coupling coefficient in nonlinear regimes. From split-step Fourier analysis of coupled nonlinear Schrödinger equations it is found that the pulse breakup occurs due to coupling coefficient dispersion. It is also demonstrated that the group velocity dispersion and its resultant pulse broadening dominate the switching behaviors of nonlinear directional coupler. To clarify the effect of intermodal dispersion, ultra-short optical pulses of 50 fs pulse duration from a mode-locked Ti:Sapphire laser are used. Comparing the experimental results with the numerical calculations, we can estimate the coupling coefficient dispersion provided that appropriate parameters are given for a nonlinear fused-tapered coupler.投稿論

    Structural Diagrams and Solid Phase Reactions of the Quaternary 7% Cr-Fe-C-N System

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    The isothermal diagrams of the 7%Cr-Fe-C-N system were studied at various temperatures from 1300°to 700℃ in the composition range up to 0.34% carbon and 0.25% nitrogen. Resorting to the consideration of the phase relationship, the phase reaction of the 7%Cr-Fe-C-N system was clarified and the sectional diagrams were constructed at fixed contents of 0.05, 0.1 and 0.2% nitrogen. In the Fe-Cr-C-N system, two quaternary peritecto-eutectoid reactions (chemical formula) exist at about 780°and 770℃, respectively

    Effect of Levels of Fertilizer Application on Vine Growth and Fruit Development of 'Kyoho' Grape Planted on a Restricted Rooting Volume

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    根域制限栽培のブドウ‘巨峰’に対する適切な施肥法を知るために,ベッド植えの1年生の木苗に液肥を週に1~3回与え,果実の発育段階に応じてその濃度を調節した.基肥としてナタネ粕を1樹当たり200g与えた区を対照区とした. 1.ナタネ粕区では開花期前に新梢の生育が弱まり,結実期後には新根の発育が1時停止した.N:60ppmを含む液肥を与えた区では新梢,根ともに正常に生育した.結実はいずれの区でも良好であった. 2.硬核期から液肥の濃度を1/3に下げると,副梢の生長が抑えられ,果粒の肥大と着色及び糖の蓄積が優れた.着色期から液肥の濃度を下げてもある程度同様の効果がみられた.N:60ppmの液肥を収穫期まで与えた区では,着色が劣り,酸含量も高かった.一方,ナタネ粕区では硬核期中の副梢の生長が旺盛で,果粒の肥大が悪かった. 3.落葉期の熱枝と根の窒素含量を比較したところ,液肥を与えた各区の方がナタネ粕区よりも明らかに高く,他の無機成分も同様の傾向であった. 4.以上の結果から,て‘巨峰’の根域制限栽培には発芽期前から液肥を施与し,着色期の前から窒素濃度を低くするのが適当であると考えられる

    Effects of a novel elastase inhibitor, ONO-5046, on nephrotoxic serum nephritis in rats

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    Effects of a novel elastase inhibitor, ONO-5046, on nephrotoxic serum nephritis in rats. ONO-5046 is a potent, specific and intravenously active inhibitor of neutrophil elastase. To examine the role of elastase in glomerulonephritis, we tested the effects of ONO-5046 on nephrotoxic serum (NTS) nephritis in a rat model of the disease in humans. Rats were administered ONO-5046 or phosphate-buffered saline (PBS) intraperitoneally 24hours prior to injection of NTS, and they were then given equal doses of ONO-5046 or PBS three hours and 1, 2, 3, 4, 5 and 6days later. Compared with the control groups, ONO-5046 significantly reduced proteinuria and hematuria, and suppressed the formation of crescentic glomeruli in a dose-dependent manner. Our results suggest that neutrophil elastase participates in NTS nephritis by degrading glomerular basement membrane proteins, and that the elastase inhibitor, ONO-5046, suppresses crescentic formation and glomerular injury caused by elastase

    Low visual information-processing speed and attention are predictors of fatigue in elementary and junior high school students

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    Background: Fatigue is a common complaint among elementary and junior high school students, and is known to be associated with reduced academic performance. Recently, we demonstrated that fatigue was correlated with decreased cognitive function in these students. However, no studies have identified cognitive predictors of fatigue. Therefore, we attempted to determine independent cognitive predictors of fatigue in these students.Methods: We performed a prospective cohort study. One hundred and forty-two elementary and junior high school students without fatigue participated. They completed a variety of paper-and-pencil tests, including list learning and list recall tests, kana pick-out test, semantic fluency test, figure copying test, digit span forward test, and symbol digit modalities test. The participants also completed computerized cognitive tests (tasks A to E on the modified advanced trail making test). These cognitive tests were used to evaluate motor-and information-processing speed, immediate and delayed memory function, auditory and visual attention, divided and switching attention, retrieval of learned material, and spatial construction. One year after the tests, a questionnaire about fatigue (Japanese version of the Chalder Fatigue Scale) was administered to all the participants.Results: After the follow-up period, we confirmed 40 cases of fatigue among 118 students. In multivariate logistic regression analyses adjusted for grades and gender, poorer performance on visual information-processing speed and attention tasks was associated with increased risk of fatigue.Conclusions: Reduced visual information-processing speed and poor attention are independent predictors of fatigue in elementary and junior high school students

    Lateral–Medial Dissociation in Orbitofrontal Cortex–Hypothalamus Connectivity

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    The orbitofrontal cortex (OFC) is involved in cognitive functions, and is also closely related to autonomic functions. The OFC is densely connected with the hypothalamus, a heterogeneous structure controlling autonomic functions that can be divided into two major parts: the lateral and the medial. Resting-state functional connectivity has allowed us to parcellate the cerebral cortex into putative functional areas based on the changes in the spatial pattern of connectivity in the cerebral cortex when a seed point is moved from one voxel to another. In the present high spatial-resolution fMRI study, we investigate the connectivity-based organization of the OFC with reference to the hypothalamus. The OFC was parcellated using resting-state functional connectivity in an individual subject approach, and then the functional connectivity was examined between the parcellated areas in the OFC and the lateral/medial hypothalamus. We found a functional double dissociation in the OFC: the lateral OFC (the lateral orbital gyrus) was more likely connected with the lateral hypothalamus, whereas the medial OFC (the medial orbital and rectal gyri) was more likely connected with the medial hypothalamus. These results demonstrate the fundamental heterogeneity of the OFC, and suggest a potential neural basis of the OFC-hypothalamic functional interaction
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