共查询到20条相似文献,搜索用时 78 毫秒
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1978年9月初在长春召开了国家科委光学及应用光学学科组会议,到会的国内知名科学家有钱临照、王大珩、苏韦、陈杏蒲、高兆兰、洪晶、张志三、胡南琦、唐九华、于家本、梅遂生、林钧挺、贾循德、吴国安、王之江、邓锡铭、干福熹、匡定波、林祥棣、龚知本、刘树杞、马林、李小琼等,王大珩是学科组组长,我是学科组秘书.在这次会议上提出了成... 相似文献
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2008年全国高考理科综合能力测试卷(Ⅰ)物理试卷供湖北、湖南、河北、河南、浙江、江西、广西、陕西、山西、安徽、福建、辽宁等省使用,全卷无超纲题、偏题、怪题,绝大部分试题及评分标准,表述科学、严谨、规范. 相似文献
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以中国著名物理学家胡刚复、饶毓泰、叶企孙、吴有训名字命名的物理学奖第三届授奖大会在北京清华大学隆重举行.王淦昌、冯端、朱光亚、黄昆、彭桓武、何泽慧、李寿楠、赵凯华、陈佳洱、杜祥琬、谢家麟、郑志鹏、叶铭汉、王书鸿等著名学者和出席中国物理学会五届二次理事会议的代表参加授奖仪式.王淦昌宣布三届物理奖评选结果:一、中国科学院高能物理所的“北京谱仪数据获取和数据处理技术”获胡刚复物理奖.获奖者是王泰杰、李卫国和许榕生三位同志. 相似文献
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《光谱学与光谱分析》2013,(2):512
《分析测试学报》是由中国广州分析测试中心、中国分析测试协会共同主办的全国性学术刊物,中文核心期刊。刊登质谱学、光谱学、色谱学、波谱学、电化学、电子显微学等方面的分析测试新理论、新方法、新技术的研究成果,介绍新仪器装置及在生物、医药、化学化工、商检、食品检验等方面实用性强的实验技术。适合科研院所、高等院校、检测机构、医药、卫生以及厂矿企业分析测试工作和管理人员阅读。 相似文献
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《中国光学与应用光学文摘》2011,(4)
1征稿范围本刊征集反映国内外光学、光电子学、光学技术应用的最新科学理论、研究成果、前沿技术和发展动态的原创性论文、技术报告、阶段性研究报告和综合评述等。2稿件要求来稿应信息准确、论点鲜明、实验数据可靠、条理清晰、文字精 相似文献
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Yahya Baykal 《Optics and Lasers in Engineering》2011,49(5):647-651
Starting from the second order moment formulation for multi-beam incidence, field correlations at the receiver plane of flat-topped Gaussian and annular beams are found in turbulence. Reflecting the information on both the randomness due to turbulence and the field profile of the incident field, field correlations of the flat-topped Gaussian beams are found to become larger at larger source size, smaller flatness parameters and smaller turbulence strengths. For the annular beam structures, field correlations are larger for thicker beams. Field correlations of larger primary beam sized annular incidences are smaller at smaller diagonal distances and larger at larger diagonal distances. As expected, annular beam field correlations are found to be larger at smaller structure constants and at smaller wavelengths. However, at large link lengths, field correlations could be larger than at smaller link lengths due to fact that for annular beams, the field at the centre of the receiver attains very small value at smaller link lengths, however, on propagation in turbulence, receiver field distribution changes to a Gaussian profile. 相似文献
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根据Hardy能流密度公式、Kubo热导率公式,推导了纳米单原子链的热传导系数公式,并进行了数值计算.研究结果表明,纳米原子链的热传导系数小于无限长原子链的热传导系数,并且纳米原子链的长度越短,则热传导系数越小.这些现象可以作如下解释:原子链可以看作是一维晶格,格波在到达原子链端点时会发生反射,而改变了格波的能量传播方向,使能流密度降低,从而使纳米原子链的热导率小于无限长原子链的热导率.并且原子链越短,格波在到达原子链端点的过程中衰减越小,从而使反射格波的能流密度越接近于入射格波的能流密度,使能流密度更为降低,从而使纳米原子链的热导率更小. 相似文献
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This paper studies negative bias temperature instability (NBTI) under alternant and alternating current (AC) stress.Under alternant stress,the degradation smaller than that of single negative stress is obtained.The smaller degradation is resulted from the recovery of positive stress.There are two reasons for the recovery.One is the passivation of H dangling bonds,and another is the detrapping of charges trapped in the oxide.Under different frequencies of AC stress,the parameters all show regular degradation,and also smaller than that of the direct current stress.The higher the frequency is,the smaller the degradation becomes.As the negative stress time is too small under higher frequency,the deeper defects are hard to be filled in.Therefore,the detrapping of oxide charges is easy to occur under positive bias and the degradation is smaller with higher frequency. 相似文献
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在Mie散射理论的基础上分析了群体粒子散射的偏振特性,并用两种不同直径(0.26 μm,0.55 μm)的球形粒子作为散射介质进行了相关实验,比较了群体粒子散射光垂直与水平偏振光的偏振度.实验发现:散射光的偏振度随粒子直径的变化呈现出一定的规律性,直径大的粒子散射光在水平方向的偏振度小于直径小的粒子;而垂直方向的偏振度却完全相反,直径大的粒子大于直径小的粒子. 相似文献
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Wide-angle neutron scattering experiments combined with Empirical Potential Structural Refinement modelling have been used to study the detailed structure of decyltrimethylammonium bromide (C10TAB) micelles at two different temperatures; 25°C and 50°C and two concentrations; 0.4 and 0.8?M in water. At higher temperature, the micelles become smaller, and fewer counterions bind to the micelle surfaces, however, the headgroup positions are more ordered, possibly due to crowding in the smaller micelles. At higher concentration, the models suggest the micelles become elongated, although the aggregations numbers are smaller than those at the lower concentration. The smaller micelles found in 0.8?M solutions have more hydrated headgroups and lower counterion binding than the ellipsoidal micelles found in 0.4?M C10TAB solutions. 相似文献
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M.N. Baibich G. Martínez M.G.M. Miranda A.T. da Rosa J. Gonzlez A. Zhukov 《Journal of magnetism and magnetic materials》2008,320(14):e29-e31
We have studied the TEM image contrasts present in micro-wires of CuCo metastable alloys embedded in glass, produced by the Taylor-Ulitovsky method. The results show that, despite a large stress induced by the glass covering, a nanostructure typical of spinodal decomposition appears. This is in all similar to the quasi-periodic stripe patterns seen in bulk CuCo ribbons made by melt-spinning we have observed previously. Also, the period seen in the micro-wires is smaller than that of the ribbons. The giant magnetoresistance (GMR) for these micro-wires is smaller than that of the ribbons, which agrees with the observation that a smaller GMR is seen when there appears an extra smaller period decomposition upon annealing. The superparamagnetic behavior is rather similar to that of the ribbons, but we are amiss of a reasonable explanation linking the lamellar nanostructure to its magnetism. 相似文献