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1.
探索了一种高比推力、高有效载荷的D-3 He聚变燃料火箭的可行性,对化学燃料火箭、裂变燃料推进器与聚变燃料火箭发射时的有效载荷份额与飞行使命的时间之间的折衷关系做了比较。从能量守恒关系分析了D-3 He聚变燃料火箭先进性的基本原理,以及运用D-3 He聚变反应作为空间飞行推进单元的优点。除了月球表层土中有丰富的氦-3资源外,也对地球外层空间中其余行星,如金星、水星和火星上的3He资源作了定量的估算。  相似文献   

2.
月球探测的进展与我国月球探测的科学目标   总被引:6,自引:0,他引:6  
在简述月球探测的历程与趋势的基础上,强调当代月球探测的总体目标为:(1)研究月球与地月系的起源和演化,特别是月球大气层与磁场的消失,矿物与岩石的分布和形成环境、月壤和内部层圈结构的形成以及月球演化的历程;(2)探测月球的资源、能源和特殊环境的开发利用及对人类社会长期可持续发展的支撑。我国不载人月球探测划分为绕、落及回三个阶段。为了全球性、整体性重新认识月球,绕月卫星探测的科学目标为获取全月面三维影像,探测14种有用元素的全球分布与丰度,探测月壤厚度并估算^3He资源量以及太阳活动对空间环境的影响。“落”为月球探测器软着陆就位探测和月球车巡视探测,建立月基光学、低频射电和极紫外天文观测平台。“回”为月球探测器软着陆就位探测和取样返回地面。  相似文献   

3.
单涛  刘树才 《科技信息》2010,(3):I0028-I0029
目前人们主要通过稀有气体同位素研究来确认流体的深部来源及计算其贡献。稀有气体各同位素(He,Ne,Ar,Ke,Xe,Rn)应用范围不一,研究程度也不相同。本文对各元素研究现状加以概述,并重点介绍He同位素研究进展,其^3He/^4He值可以很好地指示流体的深部来源。  相似文献   

4.
分析了^4He的相图和液体^4He的λ相变,讨论了在不同的温度和压强下相变的类型,指出了液体^4He被称为量子液体的基本原因,介绍了HeⅠ的基本特性,如粘滞系数、热导率,对声波的吸收系数,以及凝聚气体模型,阐述了HeⅡ的反常特性,其中最重要的是超流动性,另外,还介绍了与液体^4He相关的几种前沿应用,如超导电性,激光冷却原子和量子霍耳效应等。  相似文献   

5.
Almost all experimental and theoretical studies on regenerative cryocoolers at temperatures below 20 K mention the use of 4He as working fluid.A preliminary qualitative evaluation indicates that because of the superfluid phase transition,a working fluid of 3 He would overcome the cooling temperature limitation set by 4He.Starting with a comparison of the thermophysical properties of 3He and 4He,cryogenic regenerator simulations applied to the third/last stage of a pulse tube refrigerator,with 3He and 4He separately,were implemented to quantitatively analyze performance differences of the regenerator with respect to regenerator loss, cooling power and COP.Results conclude that 3He could significantly improve the performance of a regenerative cryocooler.  相似文献   

6.
采用反应磁控溅射法制备Er_2O_3薄膜,并利用X射线衍射仪(XRD),场发射扫描电子显微镜(SEM)对含He的Er_2O_3薄膜的结晶情况、截面和表面形貌进行表征,结果表明:无He的Er_2O_3薄膜在500℃退火时相结构基本保持稳定,在700℃退火时Er_2O_3薄膜发生明显的单斜相向立方相的转变.而含He的Er_2O_3薄膜的结晶度可能与He的存在形式有关.掺氦量较小时,未形成He泡,由于He的引入Er_2O_3薄膜的结晶度下降;随着掺氦量增加,He泡形成带来很高的内压,而在高压下Er_2O_3单斜相更易保持稳定.  相似文献   

7.
通过同时符合3He引起的核反应截面和弹性散射角分布实验数据,获得了一套适用于靶核质量数为20≤A≤209,3He入射能量从阈能到250 MeV的普适唯象光学势.对3He普适唯象光学势进行物理分析,计算和分析了3He普适唯象光学势实部和虚部的径向关系.结果表明,这套3He普适唯象光学势在物理上是合理的.  相似文献   

8.
该文用略去α集团外核子与α内核子交换的共振群方法,计算了~3He+α系统的弹性散射相移和微分散射截面。所得结果表明,α集团束缚得很紧,略去了α与~3He之间的反对称交换能得到与冗长的标准共振群方法相一致的结果。  相似文献   

9.
对14MeV中子的(n,~3He)反应截面的系统学特性作了研究,并得列了反应截面随不对称参数(N—Z)/A的增加而缓慢下降的趋势.在对实验数据分析、评价和拟合的基础上给出了一套经验参数.利用导出的系统学经验公式计算了一些核素的(n,~3He)反应截面,与实验结果比较符合较好.最后讨论了(n,~3He)反应的机制.  相似文献   

10.
探讨营养与环境因素对C3 H/He小鼠繁殖功能的影响 .观察不同营养与环境条件对C3 H/He小鼠初配产仔率、离乳仔数、体重增长等生殖、生长特性 ,并与昆明小鼠比较 .表明C3 H/He小鼠一年四季均具有繁殖能力 ,C3 H/He最长妊娠 2 4d ,最短 19d ,平均 2 0 .9d ,平均窝产仔数 4 .2只 ,较昆明小鼠有更短和更不规则的动情周期 ,营养、环境因素等影响其繁殖行为 .  相似文献   

11.
Helium-3 (3He) implanted by solar wind in the lunar regolith is a valuable resource because of its potential as a fusion fuel. On the basis of the Apollo regolith samples, a linear relationship between 3He abundance and solar wind flux, optical maturity and TiO2 content has been presented. China successfully launched its first lunar exploration satellite Chang-E 1 (CE-1) on October 24, 2007. A multi-channeled microwave radiometer was aboard the satellite with the purpose of measuring microwave thermal emission from the lunar surface layer. From the multi-channel brightness temperature (Tb) observed by CE-1, the global distribution of the regolith thickness was inverted from the multi-channel Tb, and was used to evaluate the total amount of 3He per unit area in the lunar regolith. The global inventory of 3He was estimated as being 6.6×108 kg; 3.7×108 kg for the lunar nearside and 2.9×108 kg for the lunar farside.  相似文献   

12.
月球表面核反应堆电源方案   总被引:1,自引:0,他引:1  
 月球基地的建立首先需要解决能源供给问题, 核反应堆电源具有功率大、寿命长、环境适应性强等优点, 是月球基地及其他深空探测任务的理想能源。分析了目前可用于月球基地的能源情况, 针对性地提出40 kWe月球表面核反应堆电源的设计理念, 经初步优化设计, 给出该电源的方案和总体设计参数, 并从物理、屏蔽、热工、结构方面对电源方案进行分析和论证。结果表明:该电源方案合理可行, 能够满足安全和寿期要求。  相似文献   

13.
The isotopic cumpositions of helium have been investigated in hot spring gases sampled from the Liaodong Peninsula. China. The3He/4He ratios range from 0.14 Ra (0.14 times the atmospheric3He/4He ratio of 1.40 × 10-6 to 0.72 Ra.3He/4He versus4He/20Ne ratios and He contents suggest that a small amount of mantle-derived helium reaches the earth’s surface. Helium iwtope ratios of the hot spring gases show a distribution pattern similar to the regional heat flow values, indicating that the positive thermal anomaly occurring in the rtrea is closely associated with the presence of mantle-derived helium. The observations described above provide some significant evidence that the molten magma originating from partial melting of the upper mantle may have intruded into the continental crust along the activity fault. The coupling of the presence of mantle He and heat flow anomalies to seismic activity in studied region seem to imply that there is an internal relationship between mantle degassing and seismic activity.  相似文献   

14.
A problem of petroleum energy crisis will probably be faced in the late 21st century. It is impossible to discover the giant oil fields again based on the traditional knowledge and theory of petroleum geology. From the global development point of view as well as the situation in China, the five choices of energy source in the future are to (i) extend the field of exploration in conventional petroleum and natural gas source, and exploit oil-gas source in ocean and some basins of northwestern China; (ii) discover unconventional oil and natural gas source: abiogenic gas, deep oil and gas, gas hydrates, coal bed gas and so on; (iii) develop techniques of cleansing, gasifying and liquefying coal for highly effective utilization, and transform coal into electricity and at the same time pay attention to the environment protection and pollution control as well; (iv) carry out researches on the theory and technology of producing and storing hydrogen in order to seek for its effective and economical utilization; (v) pay attention to and carry out the research in advance on exploiting the source of3He isotope on the moon and using the D-3He controlled nuclear fusion as fuel.  相似文献   

15.
煤层气的开采影响因素有很多,其中排采方式的选择是主要因素之一,而排采方式的选择主要是指排采设备的选择。沁水盆地潘河示范区排采设备单一,效率低,从实践来看,并不特别适合现场。以潘河新区煤层气开采为例,通过对该区煤层气排采设备计算分析,结合煤层气井排采曲线,基于生产时间长,少更换泵的原则对排采设备进行了优选,形成了煤层气开采设备的优选技术。该技术对今后试验区新煤层气井开发生产及地质情况相似的柿庄南开发区的煤层气井排采设备的选择具有重要意义。  相似文献   

16.
以CuO-ZnO/Al2O3复合氧化物为催化剂,采用间歇式高温高压反应釜,超临界甲醇为液化介质,对半纤维素D-(-)-阿拉伯糖进行催化液化研究.考察了反应温度、反应时间、催化剂用量、甲醇填充率对D-(-)-阿拉伯糖转化率的影响.同时采用正交试验进行优化.结果表明:当反应温度320 ℃,反应时间30 min,催化剂用量100%、甲醇填充率40%,此工艺条件下D-(-)-阿拉伯糖转化率为99.98%.通过GC-MS分析了D-(-)-阿拉伯糖液化产物,检测分析表明,其液化产物成分复杂,主要有:酯类、醇类、酮类.  相似文献   

17.
本文讨论在圆膜状和球面边界条件下,超流~3He系统诸相的纯表面缺陷的拓扑结构,给出相应的点缺陷和线缺陷的拓扑量子数.本文发现,边界条件对于~3He系统的拓扑结构的影响十分重要.  相似文献   

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