拱形与矩形断面地铁车站结构地震反应比较研究

采用动力时程法开展了拱形与矩形断面地铁车站结构地震反应的研究,分析了拱形断面和矩形断面地铁车站结构的关键截面在地震作用下的内力及变形的差异。结果表明:相比于矩形断面车站结构,拱形断面车站结构顶板边缘处和侧墙顶端的弯矩明显减小,车站侧墙顶端和顶板边缘处因承受弯矩过大而发生破坏的可能降低;内柱截面的轴压比明显减小,且与侧墙的轴压比差异显著减小,受力分配更为合理;拱形车站结构顶、底板的相对位移、内柱和侧墙的位移角相对较小。在已模拟的工况下拱形车站内力分布形式更为合理,水平变形相对较小,更有利于抗震。     

近116年江淮梅雨异常及其环流特征分析

利用江淮地区1885—2000年近116a梅雨特征量资料和NCEP／NCAR逐日再分析资料，采用谐波分析、最大熵谱分析、小波分析、合成分析等方法讨论了江淮梅雨特征量的年际-年代际变化特征及梅雨异常的环流特征。结果表明；江淮梅雨特征量存在显著的年际和年代际变化特征。入梅日期、出梅日期、梅雨期长度呈显著上升的长期变化趋势，梅雨量和梅雨强度长期趋势变化不明显；梅雨特征量均存在多时间尺度的振荡周期，入梅日期具有准24a、准5a和准3a的显著周期；出梅日期具有准35a、准22a和准5a的显著周期；梅雨量具有准40a、准15a、准9a和准3a的显著周期。丰梅年南亚高压中心强度和西太平洋副热带高压增强。枯梅年则反之。     

Characteristics of extreme daily minimum and maximum temperature over Northeast China, 1961–2009

In this study, the multifractal detrended fluctuation analysis method is employed to determine the thresholds of extreme events. Subsequently, the characteristics of extreme temperatures have been analyzed over Northeast China during 1961–2009. Approximately 58 % of stations have negative interdecadal trends of ?2.2 days/10 years to 0 days/10 years in extreme low minimum temperature (ELMT) frequency. Notable positive trend of 0–2.5 days/10 years in extreme high maximum temperature (EHMT) frequency of about 94 % stations are found. Approximately 58 % of stations have decreasing trend in ELMT intensity, whereas 69 % of stations have increasing trend of EHMT intensity. The trends are the range of ?0.72 °C/10 years to 0 °C/10 years and 0–0.7 °C/10 years, respectively. We propose the extreme temperatures indices, ELMT index (ELMTI) and EHMT index (EHMTI), which combined the frequency and intensity of extreme temperatures to represent the order of severity of extreme temperatures. According to this approach, serious ELMT mainly occur in the Songliao Plain and the Sanjiang Plain, especially in the Songliao Plain. Serious EHMT distinctly occur in the Sanjing Plain, and the southwestern and northwestern regions of Northeast China in recent five decades.     

长输埋地管道振动台试验传感器布置方案研究

在进行长输埋地管道振动台试验的过程中,针对数据信息的采集量测以及传感器的布置位置进行了研究。采用三维数值模拟的方法对管-土相互作用体系进行了地震反应分析,内容包括埋地管道结构纵、横向在非一致地震动作用下的地震响应及受力变形特征。根据计算结果确定了主观测断面及辅助观测断面的位置及观测断面上传感器布置的位置,在满足基本信息采集要求的前提下,对可供采用的信息采集通道进行了优化分配,由此确定本次试验的观测断面以及传感器的具体测量部位与数目。成果对试验获得成功起到了保障作用,可为同类试验提供参考。     

光纤耦合微通道反应系统原位监测海水氨氮和亚硝酸盐的研究

原位监测海水中氨氮（NH3-N）和亚硝酸盐（${rm{NO}}_2^- $）对于水体富营养化评价十分重要。针对现有的氨氮、亚硝酸盐原位监测仪器难以在同一检测模块中分别实现荧光和分光光度分析,仪器高效集成及利用受到限制等问题,本文基于光纤耦合微通道反应系统,通过光波长切割、光纤波导和微通道反应 Z 型检测池等技术集成和条件优化,提出了在同一光纤偶联微反应系统中实现氨氮荧光分析和亚硝酸盐分光光度分析的原位测定技术。结果表明,该技术实现了荧光和可见光光度法的模式切换并可分别测定NH3-N和${rm{NO}}_2^- $;在恒温条件下,NH3-N测定荧光信号漂移小于−2.0%,${rm{NO}}_2^- $测定吸光度稳定;不同的盐度对氨氮和亚硝酸盐测定影响较小;不同浊度下氨氮测定误差为−6.6%～2.5%,浊度补偿校正后${rm{NO}}_2^-$测定误差小于0.1%。将该仪器应用于养殖海水中开展氨氮和亚硝酸盐的原位分析,仪器原位监测值与实验室方法测定值相符合。本文所提出的技术在同一模块中分别实现了氨氮和亚硝酸盐的荧光和分光光度两种模式的原位监测,为海水营养盐原位监测仪器的集成化设计提供了新的思路。     

冰川发育对赤道地区碳酸盐沉积环境和沉积作用的影响

冰期中的全球性冰川事件不仅对全球性海平面变化，而且对低纬陆棚碳酸盐环境的沉积作用也有重要影响。与温暖时期相比，位于低纬度的华南地区在晚霞旦世冰期，晚奥陶－早志留世冰期，石炭－二叠纪冰期中记录了相对低的沉积速度和低的环境分异（反映在相的侧向变化很小）。敏一段冰期深山可以补与最大冰进所对应的海退面分为两部分。早期的沉积环境以弱咸化和富氧为特征。该环境形成浅色，相对富颗粒的灰岩沉积。随着塞冷气候的侵入，     

A Multi-Wavelength Study of the 3B/X1.2 Flare Observed on 2003 October 26

We report results from a multi-wavelength study of the 3B/X1.2 two-ribbon disk flare (S15E44), which was well observed by both ground-based and space-borne instruments. Two pairs of conjugate kernels - K1 and K4, and K2 and K3 - in the Ha images are identified. These kernels are linked by two different systems of EUV loops. Kl and K4 correspond to the two 17 GHz and 34 GHz microwave sources observed by the Nobeyama Radioheliograph (NoRH), while K2 and K3 have no corresponding microwave sources. Optical spectroscopic observations suggest that all the four kernels are possible precipitating sites of non-thermal electrons. Thus the energy of electron deposited in K2 and K3 should be less than 100 keV. Two-dimensional distributions of the full widths at half maximum (FWHM) of the Ha profiles and the line-of-sight (LOS) velocities derived from the Ca Ⅱ 8542 (?) profiles indicate that the largest FWHM and LOS velocity tends to be located near the outer edges of Ha kernels, which is consistent with the scenario of current two-ribbon flare models and previous results. When non-thermal electron bombardment is present, the observed Ha and Ca Ⅱ 8542 (?) profiles are similar to previous observational and theoretical results, while the He I 10830 A profiles are different from the theoretical ones. This puts some constraints on future theoretical calculation of the He I 10830 (?) line.     

Ertixiite—a new mineral from the Altay Pegmatite Mine,Xinjiang, China

Ertixiite (Na₂Si₄O₉), a new mineral found in a miarolitic cavity of the Altay Pegmatite Mine, Xinjiang, China, is associated with topaz, apatite, quartz, cleavelandite, etc. The mineral is white, granular, and transparent. HNV=570.08?850.96 kg/mm² (Moh’s 5.8?6.5), D=2.35, N=1.502. Cubic system,a=5.975 Å, V=213.311 Å, Z=1,D _x =2.34g/cm³. The chemical composition of ertixiite (the average of six samples) is: Na₂O 17.97, CaO 2.82, SiO₂ 77.86, Al₂O₃ 1.45, FeO 0.05, total 100.15. The strongest lines in the X-ray powder pattern are 3.443(2, 111), 2.647(2. 210), 2.674(2,210), 1.996(8,221), 1.798(10,311), and 1.492(2,400).     

黄土非饱和渗流试验研究

黄土介质特有的垂直节理和大孔隙发育性质，使黄土和非饱和渗流过程具有与均匀土壤的非饱和水分运动不同的特征。通过黄土非饱和渗流试验研究，对黄土垂直节理，大孔隙的实地观察和用土壤水动力学理论分析，证明黄土介质中的垂直节理，大孔隙在不同不量下对水分入渗所起的作用，对干旱地区黄土，由于降水量小，土壤含水量少，垂直节理，大孔隙在水分渗过程中实际起长低渗透性的作用，即阻水作用。     

济南海泡石的矿物学研究及成因

一、前言海泡石(Sepiolite)是一种罕见而有用的层状镁质硅酸盐矿物,它是热液作用或风化作用的产物,这种矿物国内过去很少发现和报导。近年来在湖南、江西等地的二叠系地层中发现具工业价值的海相沉积海泡石粘土矿床。由于它具有耐热、耐盐浸及高粘度等特性,是优质钻探泥浆原料,在地热、石油和深海钻探中尤为宝贵,在工业上十分有用。据报导,海泡石发现于1750年,但直到1937年才确定它是一种独立矿物。1955年提出海泡石的结构模型。1957年Brauner和Preisinger在前人工作的基础上对海泡石的结构