2.725K的宇宙空间背景辐射成为空间物质构成电子的证据

本文科学地将发现宇宙空间2.725K温度的背景辐射同经典物理学有机的衔接起来,并依此推导出电子的质量,由此证明电子是由宇宙空间产生的并同宇宙空间具有相同的组成成分-空间基本单元.同时根据电子经典半径r0、电子康普顿波长λe及电子质量反演出宇宙空间背景辐射温度为2.72147K.     

具有中心对称介质的三阶非线性偶极辐射

在经典物理框架内，把中心对称介质的偶板子运动方程化为了具有立方项的二阶非线性微分方程，用Jaeobian椭圆函数和第一类全椭圆积分给出了方程的解和电子振荡周期，并对偶极辐射进行了经典描述，给出了电子的辐射能量、瞬时辐射强度和平均辐射强度．     

水中放电等离子体辐射特性研究

在考虑电离能修正情况下，对水中放电等离子体(PPDW)辐射特性作了分析．结果表朗，当通道压力为1MPa时，PPDW辐射不能看作黑体辐射．当通道压力为0．1GPa、温度在16000～35000K时，PPDW满足黑体辐射的两个条件，其辐射可看作是黑体辐射．若通道压力达1GPa，则在11000～60000K范围内其辐射都可看作黑体辐射．     

超薄氩膜热传导的分子动力学模拟

采用基于经典理论的平衡态分子动力学(EMD))方法，在无量子化修正的条件下，计算了固态氩(Ar)在低于其Debye温度(92K)下的导热系数．温度在20K以上时，模拟结果和实验值吻合较好，说明固态Ar的量子化效应对其热传导性能影响不大，温度低于20K时，由于模拟区域对长波声子的裁剪作用使得模拟结果比实验值低．在此基础上，使用经典分子动力学基于三向、两向周期性边界条件的各向异性非平衡态薄膜模型，模拟了超薄Ar膜在40K的导热系数，2种模型给出了具有相同变化趋势的薄膜热传导特性曲线，即：随着膜厚的增加，导热系数增大，且模拟结果同模拟区域横截面大小无关．在相同条件下，2种模型得到的氩膜导热系数相差10％左右．     

水中放电等离子体特性的理论研究

水中放电等离子体(PPDW)具有高压、高密度和低温、低电离度的特点,人们对其辐射是否具有黑体辐射的特点一直观点不一．本计算了当通道压力为10^6pa、10^8Pa、10^9Pa,温度从3000K到60000K时PPDW的弹性、非弹性碰撞特征时间及辐射平均自由程．计算结果表明,当通道压力为10^6Pa时,通道辐射在所计算的温度范围内不能看作黑体辐射．当通道压力为10^8Pa时,通道辐射在温度从16000K到35000K范围内可看作黑体辐射．通道压力达10^9pa时,通道辐射在12000K以上均可看作黑体辐射．中还对通道电导率与其自身磁场的关系作了数值分析,结果表明只有在很低的温度和通道压力情况下才必须考虑自身磁场的影响,通常可不考虑其影响．     

准一维电子系统中磁化强度的量子受限效应

采用有效质量近似方法，计算了０Ｋ温度时准一维方形谐振势系统中电子磁化强度与化学势之间的函数关系，结果发现有比三维电子气体更为复杂的量子振荡结构，这是由于电子受电势和磁势共同束缚的结果．然而，在高温弱磁场时，这种量子受限效应就不明显，磁化强度过渡到经典情况的朗道逆磁性．     

金属立体目标的广义和狭义等效辐射截面系数

导出了金属立体目标天线温度对比度的一般表达式．类比雷达的散射截面，提出了金属立体目标的狭义和广义的等效辐射截面和等效辐射截面系数的概念，为验证狭义和广义等效辐射截面系数的可行性，计算了金属半球在混凝土背景上的天线温度对比度和等效辐射截面系数，并对误差进行了分析．计算的结果证明用狭义和广义等效辐射截面系数来计算立体金属目标的天线温度对比度是可行的．     

水中放电等离子体辐射特性研究

在考虑电离能修正情况下,对水中放电等离子体(PPDW)辐射特性作了分析．结果表明,当通道压力为lMPa时,PPDW辐射不能看作黑体辐射．当通道压力为0．1GPa、温度在16000～35000K时,PPDW满足黑体辐射的两个条件,其辐射可看作是黑体辐射．若通道压力达1GPa,则在11000～60000K范围内其辐射都可看作黑体辐射．     

微波辐射相转移催化丙二酸二乙酯的烷基化反应研究

采用微波辐射技术，以聚乙二醇400为相转移催化剂，无水K2CO3为碱．在无溶剂条件下以丙二酸二乙酯和氯化苄的烷基化为模型反应，研究了其它中长碳链卤代烃的烷基化反应。探讨了各种反应因素对产率的影响，得到最佳反应条件为．丙二酸二乙酯：氯化苄：聚乙二醇400：K2CO3=1．00：2．00：0．03：1．30（摩尔比），微波辐射350W状态下辐射4min。苄基丙二酸二乙酯的产率可达95％。     

准晶体的电子比热

计算了10次准晶体Al-Cu-Co，Al-Cu-Li和二十面体准晶Al-Mn-Si在0～1180K温度范围的电子比热，发现这些准晶体的电子比热随温度增加近似线性地增加，但其比热曲线的陡度随费米能级附近的态密度变化而发生较大变化。当电子态密度在费米能级附近的值较大时，电子比热曲线的斜率较大。如：10次准晶Al-Cu-Co，当温度到达1000K时，电子比热为0．2209kB／atom，很明显，此时电子比热不能忽略，讨论了这些准晶体中电子的化学势与温度的关系，发现其化学势随温度增加而增加，这一点准晶体与晶体材料完全不同。     

The cosmic microwave background radiation temperature at a redshift of 2.34

The existence of the cosmic microwave background radiation is a fundamental prediction of hot Big Bang cosmology, and its temperature should increase with increasing redshift. At the present time (redshift z = 0), the temperature has been determined with high precision to be T(CMBR)(0) = 2.726 +/- 0.010 K. In principle, the background temperature can be determined using measurements of the relative populations of atomic fine-structure levels, which are excited by the background radiation. But all previous measurements have achieved only upper limits, thus still formally permitting the radiation temperature to be constant with increasing redshift. Here we report the detection of absorption lines from the first and second fine-structure levels of neutral carbon atoms in an isolated cloud of gas at z = 2.3371. We also detected absorption due to several rotational transitions of molecular hydrogen, and fine-structure lines of singly ionized carbon. These constraints enable us to determine that the background radiation was indeed warmer in the past: we find that T(CMBR)(z = 2.3371) is between 6.0 and 14 K. This is in accord with the temperature of 9.1 K predicted by hot Big Bang cosmology.     

Characterizing the nonlinear growth of large-scale structure in the Universe

The local Universe displays a rich hierarchical pattern of galaxy clusters and superclusters. The early Universe, however, was almost smooth, with only slight 'ripples' as seen in the cosmic microwave background radiation. Models of the evolution of cosmic structure link these observations through the effect of gravity, because the small initially overdense fluctuations are predicted to attract additional mass as the Universe expands. During the early stages of this expansion, the ripples evolve independently, like linear waves on the surface of deep water. As the structures grow in mass, they interact with each other in nonlinear ways, more like waves breaking in shallow water. We have recently shown how cosmic structure can be characterized by phase correlations associated with these nonlinear interactions, but it was not clear how to use that information to obtain quantitative insights into the growth of structures. Here we report a method of revealing phase information, and show quantitatively how this relates to the formation of filaments, sheets and clusters of galaxies by nonlinear collapse. We develop a statistical method based on information entropy to separate linear from nonlinear effects, and thereby are able to disentangle those aspects of galaxy clustering that arise from initial conditions (the ripples) from the subsequent dynamical evolution.     

消除宇宙真空畴壁的一个可能的模型

通过对共形平直时空中具有分立对称性规范群自发破缺机制的分析,指出宇宙学相变之后尽管可以有宇宙弦和磁单极子解,但不存在Kink 解,这样消除了目前宇宙中不应出现的破坏3°K 背景辐射各向同性的真空区域结构和真空畴壁.     

A flat Universe from high-resolution maps of the cosmic microwave background radiation

The blackbody radiation left over from the Big Bang has been transformed by the expansion of the Universe into the nearly isotropic 2.73 K cosmic microwave background. Tiny inhomogeneities in the early Universe left their imprint on the microwave background in the form of small anisotropies in its temperature. These anisotropies contain information about basic cosmological parameters, particularly the total energy density and curvature of the Universe. Here we report the first images of resolved structure in the microwave background anisotropies over a significant part of the sky. Maps at four frequencies clearly distinguish the microwave background from foreground emission. We compute the angular power spectrum of the microwave background, and find a peak at Legendre multipole Ipeak = (197 +/- 6), with an amplitude delta T200 = (69 +/- 8) microK. This is consistent with that expected for cold dark matter models in a flat (euclidean) Universe, as favoured by standard inflationary models.     

宇宙背景辐射下太阳电磁辐射

宇宙中存在着温度为3K的背景辐射,故在宇宙中太阳的电磁辐射不会无穷远。利用字宙学的结果计算了微波背景辐射下太阳辐射的射程,并与地球大气中的情况做了比较。计算表明,宇宙中的辐射距离大约是地球大气中辐射距离的1亿倍。     

天文用阻挡杂质带红外探测器

低温目标红外辐射的灵敏探测和成像在航天和深空探测中具有重要的应用价值.300 K以下低温目标的辐射强度很弱,辐射特征波长位于中远红外区.阻挡杂质带红外探测器是中远红外探测器中重要的一员,具有覆盖波段宽、灵敏度高、暗电流低、抗辐射性能高等优点,能够胜任空间技术和天文探测在中远红外波段探测的苛刻要求.本文以红外天文探测对红外探测器的应用需求作为出发点,主要就国内外红外天文学、红外天文探测器发展概况,阻挡杂质带红外探测器发展历史及其材料、器件结构等方面做了简要综述,并简明扼要地介绍了阻挡杂质带探测器的器件物理模型.     

河外星际尘埃的亚毫米波发射

本文借助于观测到的大、小麦哲伦云的星际尘埃辐射，估计总星系的冷尘埃辐射对微波背景辐射的影响。结果表明：河外星际冷尘埃辐射强度强烈地依赖于宇宙减速因子，在宇宙背景探测者（ＣＯＢＤ）的观测结果的限制下，在合理的光深范围内，宇宙减速因子趋于１。     

Tracing the first stars with fluctuations of the cosmic infrared background

The deepest space- and ground-based observations find metal-enriched galaxies at cosmic times when the Universe was less than 1 Gyr old. These stellar populations had to be preceded by the metal-free first stars, known as 'population III'. Recent cosmic microwave background polarization measurements indicate that stars started forming early--when the Universe was < or =200 Myr old. It is now thought that population III stars were significantly more massive than the present metal-rich stellar populations. Although such sources will not be individually detectable by existing or planned telescopes, they would have produced significant cosmic infrared background radiation in the near-infrared, whose fluctuations reflect the conditions in the primordial density field. Here we report a measurement of diffuse flux fluctuations after removing foreground stars and galaxies. The anisotropies exceed the instrument noise and the more local foregrounds; they can be attributed to emission from population III stars, at an era dominated by these objects.     

空间目标和背景的辐照特性仿真技术研究

对空间目标和空间背景的辐照特性进行分析,建立物理计算模型.在此基础上采用计算机图形学相关的仿真方法,对不同辐照特性天体采用不同仿真手段,建立了辐照特性和仿真灰度之间的对应关系.应用表明,设计的仿真方法能可靠地仿真目标和背景的辐照特性,并且为目标和背景的外型几何特性和运动特性提供了灵活的参数控制方法.设计的仿真技术保留多个可调的参数接口,扩展性强,便于应用推广.     

COBE:宇宙学的一块里程碑——2006年诺贝尔物理学奖解读

瑞典皇家科学院将2006年诺贝尔物理学奖授予美国科学家约翰·马瑟和乔治·斯穆特,以表彰他们发现了宇宙微波背景辐射的黑体形式和各向异性。扼要地阐述了COBE的两个重要成果的物理含义。