前身星与Ⅱ型超新星爆发的数值模拟

利用考虑物质回落与混合效应的前身星输入数据,在一维球对称瞬时爆发模型下数值模拟了质量为12～15 M⊙Ⅱ型超新星的星核坍缩、激波传播、爆发能量等过程.计算结果表明:前身星的星核质量、密度、温度、物质构成等对Ⅱ型超新星爆发有重要影响,不过,数值模拟仍不能实现超新星的瞬时爆发.     

八角叶片及八角尺蠖排泄物挥发性成分测定

采用顶空固相微萃取气质联用分析法分别检测了完整的八角叶片、剪碎的八角叶片以及八角主要食叶害虫之一的八角尺蠖幼虫取食后排泄物的挥发性物质。结果表明,完整的八角叶片、剪碎的八角叶片以及八角尺蠖幼虫排泄物的挥发性物质在组成与相对含量方面均有较大差异。3种样品中分别分离鉴定出9、25和6种挥发性物质,其中在3种样品中均能检测出反式茴香醚和(Z,E)α-合金欢烯。剪碎的八角叶片以及八角尺蠖幼虫排泄物中均能检测出双环[3.1.1]2,6-二甲基-6-(4-甲基-3-戍烯基)-庚二烯。     

Comptel^26Al1.8MeV与SNR和W—R星相关分析

利用Ｃｏｍｐｅｔｌ的观测处理结果，对ＳＮＲ及Ｗ－Ｒ星与１．８ＭｅＶγ射线沿银经的分布做了拟合优度的检验和相关分析。Ｋ－Ｓ统计检验的结果认为，在α－０．１０水平上Ｗ－Ｒ星与１．８ＭｅＶ来自同样的分布，相关分析的结果也表明Ｗ－Ｒ星与１．８ＭｅＶ的分布有较好的相关性。     

电荷屏蔽与超新星前身星阶段电子丰度的变化率

超新星的前身星核心区的电子丰度 ,是Ⅱ型超新星的理论研究中最关键参数之一 .对于Ｉ型超新星 ,尽管其坍缩的主要原因是当吸积白矮星的质量超过Ｃｈａｎｄｒａｓｅｋｈａｒ临界质量时广义相对论效应引起的 ,但是电子俘获会加速其坍缩过程 .电子俘获率的高低不仅影响着前身星演化阶段中的中子剩余 ,同时电子俘获反应伴随着大量中微子的产生 ,电子俘获反应进而冷却了铁核心 .人们对超新星的前身星环境的电子俘获问题进行了广泛的研究 .Ｂｅｔｈｅ等人的研究表明 ,Ｇａｍｏｗ Ｔｅｌｌｅｒ(ＧＴ)共振跃迁能大大增加电子俘获率 ,而且可能影响前…     

新石器时代早期的陶瓷文化

文化伴随着人类的起源而出现,伴随着社会的进步而发展。新石器时代早期的陶器,文化现象就十分鲜明。从陶器的起源到万年仙人洞陶罐的纵向延伸,从磁山文化陶祖形器到大地湾文化和高庙文化彩陶装饰的横向敷陈,中华民族史前文化的神秘面纱开始层层揭开。从某种意义上说,一部中国陶瓷史,也是一部中华民族的文化史。     

格星环与格星半环

该文借鉴格环和格半环的定义,在半环,星半环的基础上,增加了一个偏序关系"≤",引入了星环、格昌环、格星半环和正星半环等定义,进一步介绍了它们的一些性质,并得到了与格环和格半环类似的几个重要命题.     

绚丽的超新星遗迹

<正>宇宙中的天体,生与死总是相依相伴。比如,中小质量恒星的死,伴随着白矮星和行星状星云的生;大质量恒星的死,伴随着中子星、黑洞和超新星遗迹的生。超新星遗迹,是大质量恒星死亡前发生灾难性的爆炸后,原来恒星包层中的物质被抛射到星际空间而形成的,而爆发后在中心留下来的核心就成了中子星或黑洞。超新星遗迹的诞生超新星遗迹的诞生,伴随着星体的剧烈爆发。这种爆发主要有两大类,一类是核燃烧导致的超新星爆发,另一类是常说的引力坍缩型超新星爆发。     

我国新石器时代晚期储粮史研究

在研究新石器时代晚期农业生产发展的表现的基础上,就这一时期的储粮概况包括储粮品种、储粮形式、储粮仓窖仓房的防潮处理、储粮用途和储粮性质进行了研究,并简要论述了新石器时代早、中、晚期储粮史之特征.     

我国新石器时代中期储粮史研究

我国新石器时代中期储粮史是早期之中后期储粮史的继承和发展,这种发展是与耜(锄)耕农业的发展并处于后期阶段密不可分的.就我国新石器时代中期的储粮形式、储粮窖穴和地上仓房的防潮措施、储粮窖穴和仓房的分布规律、储粮的种类、储粮的性质、储粮的用途和储粮的管理进行了研究.     

广西金秀县八角产业发展现状与对策

针对广西金秀县八角（Illicium verum Hook．f．）生产的现状和存在问题,提出从调整产业结构,加强市场建设与技术培训,抓好低产林改造,发展无公害产品,走特色产业化道路等方面的发展建议和对策。     

SN1987a遗留脉冲星的引力辐射

本文讨论了超新星SN 1987a遗留下来的脉冲星的引力辐射。其引力波的无量纲振幅的最大可能量级为10~(-23)。这为引力波的探测提供了一个新的希望。     

“Chi-Fang-Qi”: Is it the aureole of an ancient supernova?

An annotation for the statement about JingXing (Great Star) in the most famous Chinese ancient historical book Ski Ji Historical Records authored by Sima Qian reads as follows: “There was a red aureole (“Chi-Fang-Qi”) which connected with a deep-color aureole (“Qing-Fang-Qi”). Two yellaw stars were in the red aureole,one yellow star was in the deep-color aureole”. The author of the annotation was Meng Kang, an officer as well as a scholar of the Wei State in the Three Kingdoms period. The same records are to be found in two other Chinese histurical books compiled by the authors of later ages in Tang Dynasty——Jin History and Sui History. The scene illustrated by the record of “Chi-Fang-Qi” is very similar to the pictures of SN1987A taken by the Hubble Space Telescope. Let it be noted that although the ancient authors were often with serious wrong understandings of some astronomical phenomena such as supernovae, their depictions about natural phenomena they witnessed were mostly objective, and it was unlikely that they fictionally made the record of “Chi-Fang-Qi”. We infer that the ancient observers might have ever watched a very bright supernnva with an aureole structure in its remnant and then left such a record. Meng Kang perhaps was the first to give the record about“Chi-Fang-Qi”, and he might have lived in the period from about AD 180 to AD250, very near to AD 185. so, here the supernova the ancient people watched was most likely the one in the year of AD 185. This supposition is consistent with the distance parameter of the most possible remnant of SN185 derived by some modern measurements. If the correlation between the record of “Chi-Fang-Qi” and the supernova remnant can he further proven true, it would be an important verification of the modern theory about stellar evolution.     

远古踪迹

大理是我国西南最早开发的地区之一。从考古发掘材料来看,早在4000年前,大理就有史前人类活动的踪迹。新石器时代,大理史前人类种植水稻,饲养家畜,进行纺织、捕鱼和狩猎,居住在半穴居或干栏式的建筑之中,过着一种较为稳定的定居生活。大约在距今3000年的时候,大理地区进入了青铜时代。大理地区出土的青铜器带有明显的地域特征,在云南青铜文化中自成体系,形成了学术界一致认同的洱海地区青铜文化。     

远古踪迹《大理上下四千年》电视专题片解说词编写课题组

大理是我国西南最早开发的地区之一。从考古发掘材料来看，早在4000年前，大理就有史前人类活动的踪迹。新石器时代，大理史前人类种植水稻，饲养家畜，进行纺织、捕鱼和狩猎，居住在半穴居或干栏式的建筑之中，过着一种较为稳定的定居生活。大约在距今3000年的时候，大理地区进入了青铜时代。大理地区出土的青铜器带有明显的地域特征，在云南青铜文化中自成体系，形成了学术界一致认同的洱海地区青铜文化。     

中华文明形成的地理条件分析

国家是早期文明从产生初期发展后的产物，是对文明社会的概括。文明初曙时期的社会形态为准国家形态，中华文明始于距今5000年前后，中华文明是相对隔离的自然环境中独自形成的，是多元起源、不平衡发展的。适度的自然条件，相对封闭与隔绝的地理环境，湿暖湿润的气候，地处河湖沿岸的平原地带和温带、亚热带，是早期人类文明形成和发展的共同的地理条件。     

洱海区域新石器时代文化概述

根据现有考古资料,从考古学的角度,概述了洱海区域新石器时代文化遗址的分布与类型、文化特征及文化渊源,证实了该区域新石器文化是在古人类文化的基础上而产生,并不断地汲取其它文化因素,形成了自成一体的区域地方性新石器文化.     

有挠引力理论对SN1987A中微子两次信号的解释

用有挠引力理论的粒子运动方程探讨了ＳＮ１９８７Ａ中微子的运动，得出中微子可沿两条路径经历不同的时间到达地球的结论，对所观察到的中微子两次信号作出了比较合理的解释。     

能量色散X荧光光谱和人工神经网络在甘肃新石器时代陶片分类研究中的应用

EDXRF spectromerty was applied to provenance studies of Neolitic Age(from 6000 BCto 2000 BC)pottery sherds excavated from Gansu Province in north-west China。Major and trace components analysis of te pottery specimen was carried out,and the artificial neural networks has been used to classift the trace com-ponent of these pottery。The results shown that pottery exchange had been existed during 3000 BC in ancient Gansu Province,China。     

光速不变原理的讨论

光速不变原理是狭义相对论的两条基本原理之一。光速不变原理包含两点内容:①光速与光源运动无关;②光速不依赖于观察者所在参考系。文中讨论了这两点之间的区别。指出宋代超新星爆发事件只是有助于证明“光速与光源运动无关”,而不能证明整个光速不变原理;同时指出“光速与光源运动无关”不违反经典物理学中的伽利略变换。澄清了对光速不变原理的一些不清晰的认识。     

Relations between man and nature reflected by the evolution of the Neolithic production tools in the Three Gorges region of Yangtze River,China

The relations between man and nature reflected by evolution of Neolithic production tools in the Three Gorges region of Yangtze River is discussed in this paper.Our results show that there is a good correlation between the percentage vibration of cutting tool types and the environmental evolution indicated by the natural profile nearby.It is possible for ancestors from the Three Gorges region to learn the advantage of mortise and tenon in the early Neolithic Age because they used the stones as vital tools for processing woods.The hunting method in the early Neolithic is throwing,which was inherited in the mid-Neolithic Age when hunting with arrow and bow was developed.Fishing tools are found at the same period.Numbers of net sinkers and spinning wheels unearthed from the strata of the Western Zhou Dynasty from Zhongba Site reveal the fact of fishing with net,while a mass of fishbone pits indi- cate the powerful productivity brought by new production tools.Quantity of stone spades and stone hoes proves that cultivation agriculture by hoe is extremely attached importance by the ancestors in the Three Gorges region.Moreover,the developed agriculture in Daxi Culture at Zhongbao Island benefits from the landform,climate,traffic location,etc.Otherwise,the reason that the farming tools declined in the late Neolithic Age is related to the extreme flood during the early Xia Dynasty and the fishing hunting preference of some ancient settlements.This research shows that ancestors of the Three Gorges region during the Neolithic Age attached importance to fish hunting and cultivation, fought against the natural environment by production tools,constantly created and improved them, then comprehensively utilized them to evolve the relations between man and nature.