滚动实验的另一种演示

介绍了另一种滚动演示实验,并对演示结果进行了理论分析和解释     

利用GHZ态实现多原子缠结态的量子隐形传态(英文)

提出一种利用 GHZ态实现多原子缠结态的量子隐形传态方案 .当作为量子通道的 GHZ态含有一个单模高 Q腔时 ,大大地简化了量子稳形传态中的联合测量过程     

The synthesis of iron–nickel alloy nanoparticles using a reverse micelle technique

Nanosized Fe_0.2Ni_0.8 particles were prepared by reducing their salts with sodium borohydride (NaBH₄) in cationic water-in-oil (w/o) microemulsions of water/cetyl-trimethyl-amonium bromide (CTAB) and n-butanol/isooctane at 25 °C. According to the TEM and X-ray diffraction analyses, the synthesized particles were around 4–12 nm in size. Due to their nanodimensions, the particles had a primitive cubic (pc) structure rather than the body-centered cubic (BCC) structure of the bulk material. An examination of the synthesis from the reverse micelle reveals that the morphology of the iron–nickel alloy nanoparticles depends mainly on the microemulsion's composition. The magnetization of the nanoparticles was much lower than that of the bulk material, reflecting the influence of the nanodimensions on the particles’ magnetizations.     

The LPCTrap experiment: measurement of the β–ν angular correlation in 6He using a transparent Paul trap

We report on the status of the LPCTrap experiment, devoted to measure the β–ν angular correlation in the pure Gamow–Teller decay of ⁶He. This measurement is motivated by the search for the presence of tensor type contributions to the weak interaction. The ⁶He ions are confined in a novel transparent Paul trap. The β particles and the recoil ions are detected in coincidence to deduce the angular correlation parameter. The commissioning run performed in 2005 has given the proof of principle of this experiment. Up to 10⁵ coincidences were recorded during a second run in 2006.     

无滑动滚动时的摩擦力

通过一个演示实验 ,分析论证了纯滚动刚体所受摩擦力为静摩擦力 ,静摩擦力与物体的运动状态有关 ,与接触面性质无关 .     

不倒翁的力学分析

从力学上对不倒翁进行了分析，得出了对其配重位置的限定条件及其微振动的周期公式。     

聚异丁烯高活性端基含量及相对分子质量测定方法的研究

综合使用核磁，VPO和近红外光谱分析技术对聚异丁烯活性端基含量以及相对分子质量的测定进行了详细研究，分别建立核测定聚异丁烯活性端基含量以及其他烯键含量和近红外光谱快速测量聚异聚丁烯活性端基含量。其他烯键含量和相对分子质量的分析方法。成对t检验结果表明，近红外光谱分析方法测定结果与核磁和VPO方法测定结果之间无显著性差异。     

Calculation of heat transfer and uniformity of chemical amplification during post-exposure bake

Heat transfer in a resist-coated silicon wafer using a bake process is theoretically evaluated by modeling the three-dimensional diffusion process, focusing on the controllability of the lithographic performance of chemically amplified resists. Six models of various ambient conditions are used. The proximity gap between the hotplate and the wafer is found to have a dominant influence on the heat transfer process for the whole system. Because the atmosphere near the wafer acts as a thermal diffusion buffer layer, no temperature gradient occurs in the resist, even when it is subjected to convective heat transfer from the resist surface. Experimental results obtained by X-ray lithography confirm the calculation results.     

Synthesis and characterization of norbornene–ethylene–styrene terpolymers with a substituted ansa‐fluorenylamidodimethyltitanium‐based catalyst

This article reports a synthetic method for a norbornene–ethylene–styrene (N‐E‐S) terpolymer, which has not been well investigated so far, via incorporation of styrene (S) into vinyl‐type norbornene–ethylene (N‐E) copolymers catalyzed by a substituted ansa‐fluorenylamidodimethyltitanium [Me₂Si(3,6‐tBu₂Flu)(tBuN)]TiMe₂ catalyst ( I ) activated with a [Ph₃C][B(C₆F₅)₄]/Al(iBu)₃ cocatalyst at room temperature in toluene. The resulting terpolymerization product contained the targeted N‐E‐S terpolymer and the contaminated homopolymers, which were then able to be completely removed by solvent fractionation techniques. While homopolystyrene was easily extracted by fractionation with methylethylketone as a soluble part, homopolyethylene and a trace amount of homopolynorbornene could be perfectly separated by fractionation with chloroform as insoluble parts. The detail characterizations of a chloroform‐soluble polymer with gel permeation chromatography, nuclear magnetic resonance, and differential scanning calorimetry analyses proved that it contained a true N‐E‐S terpolymer with long N‐E sequences incorporated with isolated or short styrene sequences. The homogeneity of the morphology together with a single glass transition temperature that proportionally decreased with the increase of the styrene contents indicated that the N‐E‐S terpolymer obtained in this work is a random polymer with an amorphous structure. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 2765–2773, 2007