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本文首先运用EASY% Ro反演法对伊洛瓦底盆地由北向南进行了热史的恢复,北部钦敦凹陷的平均古地温梯度为13.0~15.0 ℃/km,中部沙林凹陷的平均古地温梯度为18.0~22.0 ℃/km,南部三角洲凹陷的平均古地温梯度为33.0~37.0 ℃/km.从模拟结果可以看出,盆地由北向南地温梯度逐渐升高,生烃门限的深度由深变浅.然后模拟了盆地的构造沉降史.模拟结果表明,盆地具有幕式构造沉降特征,这反映了伊洛瓦底盆地可能处于弧间或弧后的构造背景.伊洛瓦底盆地北部和南部具有不同幕次的构造沉降史,北部在早始新世时期(53~51 Ma)经历了一幕拉伸过程,然后进入了热沉降期,并伴随局部的快速隆升;南部则经历了两幕拉张过程,分别是在早始新世时期(53~51 Ma)和中中新世时期(21~13 Ma).盆地的这种南北构造沉降的差异很可能是造成盆地地温梯度北低南高的原因. 相似文献
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从非线性薛定谔方程出发,采用分步傅立叶分析方法数值模拟光子晶体光纤中超连续谱的产生,计算、模拟并分析初始啁啾在光子晶体光纤的零色散点对超连续谱演变和带宽的影响.结果表明,非线性作用使频谱分裂成多峰不对称的结构,初始啁啾C的引入能明显的改善超连续谱的带宽和平坦性.由于二阶色散β2=0,三阶色散猹对超连续光谱的展宽影响较大.当β3>0时,C取正值时,随着C的增大,带宽减小; C取负值时,带宽有所增大,平坦性也有改善;β3<0时,无论C取正取负,频谱带宽增大,且平坦性较好. 相似文献
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We analyze the optical spectrum of type 1 QSO SDSS J1425+3231.This object is interesting since its narrow emission lines,such as O IIIλλ4959,5007,are double-peaked,and the line structure can be modeled well by three Gaussian components:two components for the two peaks (we refer to the peaks at low/high redshift as the blue/red component) and another one for the line wing which has the same line center as that of the blue component,but is ~ 3 times broader.The separation between the blue and red components i... 相似文献
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应用µCT225kvFCB型高精度(µm级)CT试验分析系统,对直径1 mm的瘦煤从18 ℃到600 ℃高温下的热破裂过程进行了显微CT观测和分析.发现了瘦煤的热破裂规律:300 ℃煤样中大量小的孔隙贯通成大的孔隙团,因此瘦煤的热破裂阈值在300 ℃附近,从常温到300 ℃煤样的孔隙率增加了0.5倍左右.研究了煤样在100~600 ℃范围内热破裂孔隙分布的分形规律,研究发现:从100 ℃到600 ℃,煤样的分形维数D随温度升高呈现先减小、后增加的趋势.孔隙的演化规律:由初始较规则的小孔隙变形,过渡到大量较规则、小孔隙贯通成不规则的大的孔隙团,之后孔隙团缩合减小趋于规则.分布初值的对数随温度升高呈现先降低后增加的趋势;从18 ℃到600 ℃孔隙数量的演化规律为先减小后增加. 相似文献
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探究孤子自频移现象,从啁啾的角度来解释其产生的原因。运用数学求解及数值模拟方法,通过MATLAB编程画出了啁啾演变图,据此来研究自频移现象。研究结果表明,在高阶非线性效应中,脉冲内拉曼散射、色散和自相位调制共同所致的啁啾,与无拉曼散射效应时产生的啁啾相比,发生一系列新的变化:啁啾的中心发生漂移且图形的前后沿不对称,即负啁啾的峰值的绝对值大于正啁啾的峰值,这说明了脉冲频谱“红移”的谱峰变宽,或者说频谱移向了长波长方向—即人们所说的孤子自频移现象。 相似文献
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Fang Yang Chen Hu Yan-Mei Chen Jian-Min Wang 《中国天文和天体物理学报》2007,7(3):353-363
We compiled a sample of 98 radio-quiet active galactic nuclei observed by ASCA, Chandra, XMM-Newton, INTEGRAL and Swift with the aim of testing the formation of hot corona and the magnetic shear stress operating in a disk-corona system. We found a strong correlation between the hard X-ray luminosity, bolometric luminosity L Bol and Eddington luminosity LEdd, in the sense that the fraction f of hard X-ray to the bolometric luminosity is inversely proportional to the Eddington ratio. This correlation favors the shear stress tensor being of the form of trφ∝ Pgas, with which the disk-corona structure is stable. 相似文献
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We investigate the MBH-O'.relation for radio-loud quasars with redshift z<0.83 in Data Release 3 of the Sloan Digital Sky Survey (SDSS).The sample consists of 3772 quasars with better models of the H/~ and [O III] lines and available radio luminosity,including 306 radio-loud quasars,3466 radio-quiet quasars with measured radio luminosity or upper-limit of radio luminosity (181 radio-quiet quasars with measured radio luminosity).The virial supermassive black hole mass (MBH) is calculated from the broad H/line,and the host stellar velocity dispersion (σ*) is traced by the core [O III] gaseous velocity dispersion.The radio luminosity and radio loudness are derived from the FIRST catalog.Our results are as follows:(1) For radio-quiet quasars,we confirm that there is no obvious deviation from the MBH-O".relation defined for inactive galaxies when the uncertainties in MBH and the luminosity bias are concerned.(2) We find that the radio-loud quasars deviate more from the MBH-σ.relation than do the radio-quiet quasars.This deviation is only partly due to a possible cosmological evolution of the MBH-σ* relation and the luminosity bias.(3) The radioluminosity is proportional to M128 0.23-0.16 BH(LBol/LEdd)1.29 0.31-0.24 for radio-quiet quasars and to M3.10 0.6.-0.70(LBol.LEdd)4.18 1.40-1.10 for radio-loud quasars.The weaker dependence of the radio luminosity on the mass and the Eddington ratio for radio-loud quasars shows that other physical effects would account for their radio luminosities,such as the spin of the black hole. 相似文献
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Previous statistical analyses of a large number of SOHO/MDI full disk longitu-dinal magnetograms provided a result that demonstrated how responses of solar flares to photospheric magnetic properties can be fitted with sigmoid functions. A logistic model reveals that these fitted sigmoid functions might be related to the free energy storage process in solar active regions. Although this suggested model is rather simple, the free energy level of active regions can be estimated and the probability of a solar flare with importance over a threshold can be forecast within a given time window. 相似文献
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Yong-Yun Chen Yan-Mei Chen Qiu-Sheng Gu Yong Shi Long-Ji Bing Xiao-Ling Yu 《天文和天体物理学研究(英文版)》2019,(6):51-62
We select 107 blue-core galaxies from the MaNGA survey, studying their morphology, kinematics as well as the gas-phase metallicity. Our results are as follows:(i) In our sample, 26% of blue-core galaxies have decoupled gas-star kinematics, indicating external gas accretion;15% have bar-like structure and 8% show post-merger features, such as tidal tails and irregular gas/star velocity field. All these processes/features, such as accreting external misaligned gas, interaction and bar, can trigger gas inflow. Thus the central star-forming activities lead to bluer colors in their centers(blue-core galaxies).(ii) By comparing with the SDSS DR7 star-forming galaxy sample, we find that the blue-core galaxies have higher central gas-phase metallicity than what is predicted by the local mass-metallicity relation. We explore the origin of the higher metallicity, finding that not only the blue-core galaxies, but also the flat-gradient and red-core galaxies all have higher metallicity. This can be explained by the combined effect of redshift and galaxy color. 相似文献