中日宇宙线观测研究成果举世瞩目

宇宙线和超高能天体物理是当代基础科学的重要前沿学科。我国和日本在西藏进行的宇宙线合作研究,是当前我国宇宙线研究的重要组成部分。由于在高海拔的地面可以观测到更多的宇宙线高能粒子,宇宙线研究最好能在数千米高山上进行,而日本没有４０００米以上的高山。中日两国的合作研究酝酿于１９７８年,正式合作从１９８０年开始。实验基地设在拉萨附近的曲水县甘巴拉山（海拔５５００米）上,探测手段是由铅板和Ｘ光片组成的量能器,主要记录超高能宇宙线粒子在大气中产生的空气簇射的轴心附近的高能粒子束,进而研究粒子核作用特性和原初…     

西藏羊八井宇宙线国家野外观测研究站的建设、运行与发展

1科学背景宇宙线是来自宇宙深处的高能粒子流,主要由质子和多种元素的原子核组成,它携带着宏观宇宙、微观世界和空间环境的科学信息,联系着宇宙的历史、天体的演化、空间     

基于RS/GIS的三江源地区太阳能资源遥感估算方法研究

利用风云系列静止气象卫星可见光通道的行星反照率和红外通道亮温,依据地球-大气系统的物理模式反演得到三江源地区太阳总辐射。本文在Dedieu模式的基础上,考虑了高程、气溶胶、云和水汽的变化对晴天地表太阳辐射的影响,同时结合2005年-2007年玉树、玛沁两站地面实测辐射资料对模型参数修正,反演得到了地面的太阳总辐射;反演数据与地面辐射站直接测量的结果进行了比较分析,小时、日辐射相关系数达0.92以上,晴天两者的差别在5%以内,绝对误差在2MJ/m2以内。小时太阳总辐射时间尺度上开口向下抛物线,最大值在中午13时左右,最小值出现19时;日太阳辐射波动变化,日最大值约为42.50MJ/m2,最小值为1.38MJ/m2;在对计算地表太阳总辐射的经验公式进行时间推广时,根据梯形积分的思想,计算日太阳总辐射,反演值与实测值一致性较高。从月太阳总辐射空间分布图分析,年内选择辐射最大月份7月份分析,三江源地区7月份太阳总辐射在(500～800)MJ/m2之间,并呈从西到东减少趋势,最大值分布主要集中在可可西里地区,最小值集中在东南部地区。研究该区域太阳能其分布特征不仅可以拓展清洁能源的利用,而且有利于三江源地区植被生态环境保护。     

消费者知识对高新技术标准产品创新扩散影响研究——以蓝光DVD播放器为例

 以变得蓝光DVD播放器为例,分析了消费者知识（包括产品知识和使用经验）对高新技术产品创新扩散的影响,以及消费者创新性和产品兼容性的调节作用。采用两个组间实验设计,结果表明：消费者的产品知识对创新扩散影响不显著,使用经验影响显著;当消费者创新性高时,产品知识的影响变得显著,使用经验影响增加;当产品兼容性高时使用经验影响显著增加,产品知识的影响则不显著。因此在高新技术产品创新扩散中使用经验比产品知识重要,消费者创新性和产品兼容性对产品知识和使用经验的调节作用不同。企业应根据这些特点制定相应营销策略,以提高高新技术产品创新扩散的速度。     

The variation of the residual ionization with pressure at different altitudes,and its relation to the cosmic radiation

Measurements have been made of the residual ionization in a closed vessel of steel one inch thick, shielded by a two inch casing of lead, over a range of pressure from atmospheric to one thousand pounds per sq. inch, at Pike's Peak (alt. 14,000 ft.), Colorado Springs (alt. 6,ooo ft.), and New Haven (alt. 6,000 ft.). The ionization-pressure curves presents features of interest in relation to the interpretation of the processes associated with ionization in the vessel. However, in the present investigation they are used simply to obtain average relative value of the ionization due to the cosmic rays at the three altitudes concerned. A method of correcting the observations for absorption by the iron sphere, the lead case, and the walls of the buildings, has been developed. It is found that the data for the three stations can be correlated by the assumption of a pair of frequencies in the original cosmic radiation; and, as a matter of fact, an infinite number of such pairs are possible. They are represented in graphical form in Fig. 7 If we permit the assumption of three different frequencies in the cosmic radiation, it is possible in general to assign two of the frequencies, and determine an infinite number of possibilities as regards the third, distributed over a definite range. The possibilities inherent in the assumption of three frequencies are contained in tabular form in Table XVII. Of course, the inclusion of observations from more than three altitudes would serve to fix more definitely the possibility as regards the analysis. However, the result of the analysis for the three stations concerned is possibly of interest for comparison with other data, and as an indication of the kind of information which it is possible to extract from observations of this kind. It is probable that the very large range of possibilities inherent in a solution with three coefficients of absorption will be rather surprising to anyone who considers a situation of this kind for the first time.In addition to those whose assistance has already been acknowledged, I wish to acknowledge the assistance of Professor J. W. Broxon, who visited me while on Pike's Peak, and assisted in setting up the apparatus; and my thanks are due to Mr. C. A. Kotterman, and particularly to Mr. Andrew Longacre, and Mr. W. E. Ramsey for assistance in the reduction of the observations, and in the computational work.