150个银河系球状星团的空间分布研究

采用银河系中150个球状星团作为样本,对其在银心坐标系中的空间分布特征进行了分析研究.结果表明:①样本中94%的球状星团分布在银纬-50°～+50°之间,银纬+50°～+70°度之间和银纬-50°～-70°之间几乎没有球状星团;②样本星团相对经纬度而言分布不均匀,分别在银经10°和350°处出现了两个分布峰值;③样本中距银心最近的球状星团的银心距为0.68kpc,最远银心距为123.33kpc,68.7%的样本球状星团分布在距银心10kpc以内,样本星团相对银心呈球对称分布.     

湿度影响下的重载交通沥青路面动力响应

考虑地下水和雨水入渗的影响,运用ABAQUS软件建立重载交通沥青路面动力分析模型,分析地下水上升和降雨入渗引发路基湿度变化后的路基动态回弹模量分布规律,以及三轴双轮移动重载作用下沥青路面的动力响应.分析结果表明,地下水距路基顶面越近,对路基模量的分布影响也越显著,降雨入渗与动载共同作用处的路基模量折减更明显;地下水位距路基顶面高度从6 m减至2 m时,面层层底拉应变由70×10~(-6)增至173×10~(-6);降雨强度增大对外侧车道处的面层层底拉应变影响巨大,对中间车道的影响较小;降雨天数增加,两侧车道的面层层底拉应变反而减小,而中间车道的趋势相反,拉应变随着降雨天数增加而增大.     

基于罗森-拉姆勒分布函数的粉尘分散度分析

根据罗森-拉姆勒分布函数推导粉尘分布规律的原理,对王庄煤矿4339工作面四个点的粉尘粒度分布数据进行回归处理后,得出该工作面的粉尘粒度分布规律. 结果表明:进风巷距工作面5m处粒径为5μm以下的粉尘占14.8%,5～10μm的占32.5%,10μm以上的为52.7%,粉尘粒度集中分布在5～20μm;转载点粉尘粒度集中分布在5～10μm;工作面50#支架处的粉尘粒度集中分布在5～10μm;回风巷离工作面20m处的粉尘分散度集中分布在5～20μm. 依据各点粉尘粒度集中分布的特点提出相应的防尘建议.     

空旷环境下小药量集中药包爆炸冲击波衰减规律

为研究炸药爆炸冲击波在空旷环境下的传播规律,采用NUBOX9100冲击波信号分析仪分别对0.1、0.2和0.3 kg的小药量集中药包进行了现场试验。试验表明:小药量集中药包爆炸冲击波在空旷环境下传播速度随爆心距衰减较快,在爆心距12 m处的冲击波传播速度衰减速率为爆心距2 m处的60%。当爆心距在1～3 m时,冲击波超压峰值的衰减速率约为75.61 kPa/m;爆心距在3～8 m时衰减速率降低到10.12 kPa/m;爆心距大于8 m时,衰减速率趋于平缓,约为0.48 kPa/m。提出了冲击波超压峰值与比例距离之间的修正公式,修正公式尤其对比例距离大于10的情况进行了修正。在比例距离较大时,修正公式比以往的经验公式更适用。运用ANSYS/LS-Dyna软件对炸药在空旷环境下爆炸冲击波超压衰减进行了模拟,结果表明修正公式的误差较小。     

基于偏振态颜色编码的晶体应力双折射成像

提出了一种基于双线偏振CCD-全Stokes参量测量的偏振态色度成像新方法.通过分焦面Stokes参量测量与RGB颜色编码相结合,设计并研制了基于双线偏振CCD-全Stokes参量测量的偏振态色度成像系统.利用该系统,获得了晶体模型应力双折射分布的偏振态色度图像,并与传统的光弹性应力测量法进行了比较,偏振态色度成像法不...     

新建隧洞下穿爆破对公路隧道结构的影响： 以温州市瓯江引水工程为例

为了探寻爆源逐步接近既有隧道情况下衬砌受爆破振动的响应规律、爆破荷载作用下的应力分布状态,结合温州市瓯海区西山隧洞工程,根据施工现场爆破监测数据和数值模拟结果对新建隧道爆破施工时相交隧道的安全性进行研究,研究结果表明振速主要受到爆心距和装药量的影响：爆心距越小装药量越大,振速峰值越高;爆心距决定隧道衬砌合速度峰值发生位置;衬砌合速度峰值位置同时是最大拉应力点;随爆心距的缩进,危险点从拱腰位置移动到拱脚。     

组合赋权下的调心滚子轴承响应面MOGA优化模型

为了提升调心滚子轴承响应面应力分布均衡性,解决由调心滚子轴承响应面产生应力变化,导致调心滚子轴承失效问题,提出一种调心滚子轴承响应面优化方法。建立调心滚子轴承响应面客观赋权模型,通过Hertz接触理论分析响应面线性应力分布情况。采用多目标遗传算法(Multi Objective Genetic Algorithm, MOGA)对响应面有限元模型加以最优量优化,完成响应面优化模型构建。实验结果表明：响应面应力分布优化测试曲线整体平稳,起始值与终止值相差较小,并且整体值域有明显提升;目标模型对于连续性暴力压力受力较均匀。由此证明,目标模型在响应面应力分布优化方面效果明显,能够保证参量的统一,具有一定的稳定性、可靠性及有效性。     

蠕变对预变形Super 304H奥氏体不锈钢沉淀析出行为的影响

采用维氏硬度计测试分析了蠕变对预变形的Super 304H奥氏体不锈钢硬度的影响,并利用透射电镜（TEM）结合能谱分析仪对析出相的形状、大小、分布特征、晶体结构以及化学成分进行了分析。分析结果表明：Super 304H不锈钢在蠕变过程中先发生强化现象后发生软化现象,随着蠕变时间的增加,析出相逐渐增多;在蠕变过程中,Super 304H不锈钢在晶界处析出不连续的面心立方的（Cr,Fe）23C6碳化物颗粒,在晶粒内部和晶体缺陷处析出的是面心立方的NbC颗粒。     

不同破断距下开采覆岩裂隙网络分形特征研究

为研究神东矿区不同破断距下开采覆岩裂隙网络分形特征,分析了基本顶周期破断距影响因素,选取大柳塔煤矿52505和上湾煤矿12401工作面进行物理相似模拟实验,探究了不同破断距影响下覆岩裂隙网络分布特征,借助Matlab软件获取不同覆岩裂隙网络分布分形维数,定量描述了覆岩裂隙发育特征,进一步探讨了覆岩裂隙传播影响下不同岩层沉降规律。研究结果表明：影响基本顶周期破断距主要因素包括基本顶厚度、抗拉强度以及承载载荷;大柳塔52505工作面、上湾12401工作面模拟开采平均破断距分别为20和30.4 m;不同破断距下覆岩裂隙网络的分形维数随煤层工作面推进呈现阶梯形增长态势,分形维数可较好地表征覆岩裂隙分布。两工作面最高离层裂隙发育高度与分形维数变化趋势均近似呈非线性正相关;不同破断距对覆岩整体裂隙发育扩展趋势影响显著,工作面回采前期大柳塔52505工作面分形维数相对较低,回采中后期则相反,破断距小,覆岩整体裂隙发育程度相对较高;两工作面覆岩沉降曲线呈“凸”型,近似以采空区中部对称。     

各向异性无源光腔的偏振特性

本文采用Stokes偏振矢量处理各向异性无源光腔的偏振特性,给出行波埸的Stokes偏振矢量的运动方程,导出真实的各向异性无源腔的本征偏振态、本征频率和频率裂距的解析式。并进一步地推广了光学等效原理,讨论了色散对频率裂距的影响。     

A review of recent studies on coronal dynamics: Streamers, coronal mass ejections, and their interactions

In this article I present a review of recent studies on coronal dynamics, including research progresses on the physics of coronal streamers that are the largest structure in the corona, physics of coronal mass ejections (CMEs) that may cause a global disturbance to the corona, as well as physics of CME-streamer interactions. The following topics will be discussed in depth: (1) acceleration of the slow wind flowing around the streamer considering the effect of magnetic flux tube curvature; (2) physical mechanism accounting for persistent releases of streamer blobs and diagnostic results on the temporal variability of the slow wind speed with such events; (3) force balance analysis and energy release mechanism of CMEs with a flux rope magnetohydrodynamic model; (4) statistical studies on magnetic islands along the coronal-ray structure behind a CME and the first observation of magnetic island coalescence with associated electron acceleration; and (5) white light and radio manifestations of CME-streamer interactions. These studies shed new light on the physics of coronal streamers, the acceleration of the slow wind, the physics of solar eruptions, the physics of magnetic reconnection and associated electron acceleration, the large-scale coronal wave phenomenon, as well as the physics accounting for CME shock-induced type II radio bursts.     

1997年3月9日日食时的日冕结构和光度测量

在１９９７ 年３ 月９ 日日全食时, 我们于黑龙江省漠河市（ 西林吉） 作了一系列日冕的照相观测不同感光的日冕像上显示出赤道东西的宽冕流、两极区冕洞、极羽和２０ 多条极射线等结构特征本文综合一些日冕像的形态结构和亮度测量结果,给出日冕的形态结构图、等亮度图、两极区和赤道区东西的亮度分布图     

Coronal structure and brightness profile of the total solar eclipse on August 1, 2008

Solar corona is the outermost part of the solar atmosphere. Coronal activities influence space environment between the Sun and the Earth, space weather and the Earth itself. The total solar eclipse （TSE） is the best opportunity to observe the solar corona on ground. During the TSE 2008, a series of images of the corona and partial eclipse of solar disk were obtained using telescope and CCD camera. After image processing, preliminary results of coronal structure are given, and radial brightness profiles of the corona in directions of pole and equator of the Sun are measured. Though in solar activity minimum, the shape and structure of the corona are not symmetry. The equatorial regions are more extent than the polar one, and there are also larger differences between the east and west equatorial regions and between the south and north polar regions. Coronal streamers on east side of the equator, particularly the largest one in east-south direction, are very obvious. The coronal plume in south polar region consists of more polar rays than that in north polar region. These structures are also shown in other observations and data of SOHO. The radial brightness profiles in directions of pole and equator are similar to those of the Van de Hulst model in solar minimum, but there are a few differences due to coronal activity, which is shown in the isophote map of the corona.     

冕洞面积与绿日冕亮度间的一些统计关系

研究了冕洞面积与绿日冕高度在太阳活动２０，２１，２２周中的一些关系：１）冕洞总面积的最大值，最小值出现在绿日冕亮度差率为一些定值处；２）当冕洞总面积是最大或最小值时，绿日冕亮度减小为０．３１～０．６１相对强度单位或０．１０～０．１１相对强度单位。     

Selective absorption processes as the origin of puzzling spectral line polarization from the Sun.

Magnetic fields play a key role in most astrophysical systems, from the Sun to active galactic nuclei. They can be studied through their effects on atomic energy levels, which produce polarized spectral lines. In particular, anisotropic radiation 'pumping' processes (which send electrons to higher atomic levels) induce population imbalances that are modified by weak magnetic fields. Here we report peculiarly polarized light in the He I 10,830-A multiplet observed in a coronal filament located at the centre of the solar disk. We show that the polarized light arises from selective absorption from the ground level of the triplet system of helium, and that it implies the presence of magnetic fields of the order of a few gauss that are highly inclined with respect to the solar radius vector. This disproves the common belief that population imbalances in long-lived atomic levels are insignificant in the presence of inclined fields of the order of a few gauss, and opens up a new diagnostic window for the investigation of solar magnetic fields.     

偏振光杨氏实验特性分析

本文分析了偏振光杨氏干涉实验中条纹的可见度及亮度随各偏光镜取向的变化关系,并与非偏光杨氏实验的结果进行了比较。     

基于红外遥控的大功率LED色温和亮度独立控制系统设计

为进一步改善LED室内照明光源质量和智能化控制,设计了基于红外遥控的大功率LED色温和亮度独立控制系统.系统采用薄荷白、红、蓝三色LED混合成白光,通过红外遥控调节LED色温和亮度的独立变化,实现色温动态变化.实验结果表明,系统可实现2 700~6 500K的宽色温范围,调节准确.     

Single-fluid 2D magnetohydrodynamic simulation of solar wind structure in comparison to ulysses observations

Two dimensional Magnetohydrodynamic (MHD) equations with and without the momentum addition respectively have been used to simulate the solar wind structure on the meridian plane. The results show that far away from the sun it isn't solar magnetic field that induces the cncave solar wind speed. Instead, there may be the fast speed streamer driven by the momentum addition and an interface between high and low speed streamers. The interaction between high and low speed streamers causes the sharp division. Foundation item: Supported by the National Natural Science Foundation of China (4999045) Biography: Deng Ling-yun (1976-), female, Master candidate, research direction: solar-terrestrial physics.     

旋转式天空偏振光的航向角检测系统

为了提高点源式偏振光探测器的可靠性和精度,在斯托克斯(Stokes)矢量的偏振光测量原理的基础上采用单个偏振光传感器通道设计并且搭建了 一种快速旋转式天空偏振光信息探测系统,通过GPS授时确定太阳子午线的位置,进而实时解算出航向角数据,在室内和天气晴朗、空旷的室外条件下完成了数据采集,最大误差为1.047°,平均误差为...     

采用遗传算法的LED太阳光谱仿真

基于简单遗传算法,通过求解超定方程组的非负最小二乘解,优化单色发光二极管(LED)匹配光源组合,实现用白光LED取代部分单色LED模拟太阳光谱,并讨论白光LED可以取代几种不同峰值波长的LED.仿真结果表明:在300~1 100 nm范围内,随着白光LED取代单色LED种类的增加,所用LED总数减少,光谱匹配度均下降;当取代3种不同峰值波长LED时,该算法拟合的相关指数为0.903 5,可减少15.6%的LED个数,模拟光谱与目标光谱基本吻合.该方法的光谱失配度小,可精确分辨标准太阳光谱AM1.5的两个吸收谷.