1—(3—吡啶甲酰)—4—芳基氨基硫脲类和3—(3—吡啶基)—4—芳基—1,2,4—三唑啉—5—硫酮类化合物~(13)C—NMR谱研究

本文测定了1-(3—吡啶甲酰)—4—苯基氨基硫脲、3—(3—吡啶基)—4—苯基—1,2,4—三唑啉—5—硫酮等8个新化合物的~(13)C NMR谱,运用质子宽带去偶、偏共振去偶,结合信号强度对比、苯基取代基效应的计算,同时与模型化合物对照,一一归属了其谱峰。本文对这两类化合物之间的~(13)C NMR谱差异进行了探讨,并得到了在吡啶环3位取代的甲酰肼基对吡啶环各碳取代基效应的数据。     

Y—Ba—Cu—Sn—O高温超导体

用Sn分别部分替代Y-Ba-Cu-O系超导体中的Y或Cu,制备了Y-Ba-Cu-Sn-O系超导体,实验结果表明,在相当大的替代范围(30%的 Y,40%的 Cu)内,超导体仍保持正交结构,其零电阻转变温度基本上稳定在90K左右.     

1—(4—吡啶甲酰)—4—芳基氨基硫脲类和3—(4—吡啶基)—4—芳基—1,2,4—三唑啉—5—硫酮类化合物~(13)C—NMR谱研究

本文测定了新合成的,具有生理活性的1-(4-吡啶甲酰)-4 -苯基氨基硫脲,1-(4-吡啶甲酰)-4-对氯苯基氨基硫脲,1-(4 -吡啶甲酰)-4-对溴苯基氨基硫脲3-(4-吡啶基)-4-苯基-1,2,4,-三唑啉-5-硫酮,3-(4-吡啶基)-4-对氯苯基-1,2,4,-三唑啉-5-硫酮,3-(4-吡啶基)-4-对溴苯基-1,2,4-三唑啉-5-硫酮六个新化合物的~(13)C-NMR谱,并通过~(13)C-NMR谱中的宽带去偶,偏共振及APT技术,模型化合物对照,讯号强度对比及芳基取代基常数计算等方法,进行了上述化合物~(13)C-NMR谱峰的归属,并得到了甲酰肼基在吡啶环4位取代后对吡啶环各碳所产生的取代基效应.     

居里夫人—施士元—吴健雄

施士元先生于2007年9月28日从容走完了他百年人生.他l929年毕业于清华,适逢江苏省招考公费出国留学生,施士元和王淦昌等清华同学一起去报考,凭着清华4年功底,他和王淦昌同时在300多考生中脱颖而出.他选择去法国留学,     

为科学献身的物理学家 — — — 利赫曼

乔治·威廉·利赫曼是与人们熟知的本杰明·富兰克林同时代、 同样研究过雷电的物理学家. 他在电学 领域做了一些开创性贡献, 不仅是俄国最早一批研究电学的人, 而且是世界上成功制成验电器的第一人. 由于利赫 曼在1 7 5 3年被雷电击中身亡, 导致中学教师在引用与利赫曼有关的物理学史时将着眼点只放在其死亡上, 且不够 详实准确. 目前在国内能够查阅到的中文资料有限且零散, 所以本文将主要借助外文文献, 从生平、 科学成就以及其 死亡的整个过程等方面梳理利赫曼的一生, 以帮助中学教师全面地了解这位为科学献身的物理学家     

2005——世界物理年

 1905年,年仅26岁的天才物理学家爱因斯坦连续发表了5篇极具震憾力的物理学论文,论文包括现代物理学中的3项伟大的成就:分子运动论、狭义相对论和光量子假说,从根本上改变了物理学的面貌,并为相对论的建立与发展奠定了基础,这一年被称为“奇迹年”。在这“奇迹年”100周年到来之际,全球物理学界一致呼吁把2005年定为“世界物理年”,这项倡议由欧洲物理学会提出,得到了国际纯粹与应用物理联合会的一致通过。     

High—Efficiency Organic Double—Quantum—Well Light—Emitting Devices Using 5,6,11,12—Tetraphenylnaphthacene Sub—monolayer as Potential Well

The double-quantum-well organic light-emitting devices of indium-tin-oxide (ITO)/NPB (50nm)/rubrene (0.05nm)/NPB (4nm)/rubrene (0.05nm)/Alq3 (50nm)/LiF (0.5nm)/Al were fabricated, in which N,N-bis-(1-naphthyl)-N,N‘-diphenyl-1,1‘-biphenyl-4,4‘‘‘‘‘‘‘‘-diamine (NPB) is used as a barrier potential or hole transport layer, tris (8-hydroxyquinoline) aluminium (Alq3) used as electron transport layer, and 5,6,11,12-tetraphenylnaphthacene (rubrene) as a potential well and emitter. The brightness can reach 18610cd/m^2 at 13V. The maximum electroluminescent efficiency of the device was 6.61cd/A at 7V, which was higher than that of common dope-type devices. In addition, the electroluminescence efficiency is relatively independent of the drive voltage in the range from 5 to 13V.     

Einstein——Podolsky——Rosen entanglement in time-dependent periodic pumping non-degenerate optical parametric amplifier

The solution of the time-dependent periodic pumping non-degenerate optical parametric amplifier (NOPA) is derived when the pump depletion is considered both above and below thresholds. Based on this solution, the quantum fluctuation calculated shows that a high entanglement and a good squeezing degree of the parametric light beams are achieved near and above thresholds. We adopt two kinds of pump fields: (i) a continuously modulated pump with a sinusoidal envelope; (ii) a sequence of laser pulses with Gaussian envelopes. We analyse the time evolution of continuous variable entanglement by analytical and numerical calculations, and show that the periodic driven pumping also improves the degree of entanglement. The squeezing and Einstein-Podolsky-Rosen (EPR) entanglement by using the two pumping driven functions are investigated from below to above the threshold regions, the tendencies are nearly the same, and the Gaussian driven function is superior to that of the sine driven function, when the maximum squeezing and the minimum variance of quantum fluctuation are considered. In the meantime, the generalization of frequency degenerate OPA to frequency non-degenerated OPA problem is investigated.     

5—芳胺—6—氯—2,3—二氰吡嗪的二阶非线性光学活性研究

合成了８个５－芳胺－６－氯－２，３－二氰吡嗪新化合物，用溶剂化变色法测定了它们的微观二阶谐波系数和其基态偶极距的复合量，表明它们的微观二阶谐波系数均有较大值，用粉末法测试了它们的宏观倍频效应，它们都具有一定的倍频效应，有可能在这类物质中找到有用的有机非线性光学材料。     

铀—Br—PADAP—磺基水杨酸—表面活性剂体系的研究

本文研究了铀（Ⅵ）－Br－PADAP－磺基水杨酸三元络合物分别与阳离子表面活性剂溴化十六烷基吡啶（CPB）、溴化十六烷基三甲基铵（CTAB），非离子表面活性剂聚乙二醇辛基苯基醚（OP）、Triton X-100的反应条件、生成物的性质和其组成，对反应机理进行了初步讨论。     

完美数据 — — — 实验教学的美丽误区

通过对自由落体运动和库仑定律的实验方案选择案例分析, 阐述教学实验不能一味追求数据完美, 而 忽视实验思想方法教育的教学观点     

Copper Defects and Conductivity in Bi—Pb—Sr—Ca—Cu—O Glasses

Glass ceramics of the composition (Bi_0.8Pb_0.2)₄Sr₃Ca₃Cu₄O₈ prepared by the melt quenching technique and the crystalline phases produced by the rapid thermal annealing have been studied by electrical resistivity and electron paramagnetic resonance (EPR) measurements in the temperature range from liquid helium up to room temperature. The concentration of the EPR active Cu^2? paramagnetic centers decreases as conductivity increases for the glass ceramics and disappears after crystallization and the growth of superconducting phases, similar to bulk high-T_c superconductors. The KPR spectra of both glass and crystallized ceramics after short-time annealing indicate the coexistence of Cu^2? paramagnetic ions and the exchange coupled clusters.     

熔融浇铸法合成Bi—Sr—Ca—Cu—O高温超导体

将 Bi_2O_3,SrCO_3,CaCO_3,CuO 按比例混合和熔融,化合成 Bi-Sr-Ca-Cu-O 复合氧化物,浇铸成型;经高温退火处理获得起始转变温度117K,零电阻温度79K 的多相超导体.此法与通常的烧结法进行了对比.