小磁岛转动引起的沿磁力线电流对撕裂模的影响

利用离子香蕉轨道中心坐标和香蕉轨道平均算符,讨论了磁岛转动引起的沿磁力线电流分布及其对新经典撕裂模演进的影响。结果显示,考虑此电流的影响,当磁岛旋转频率ω=ω_*i 时,被离子香蕉轨道宽度效应削弱的自举电流驱动项基本恢复;当ω=ω_*e时,离子香蕉轨道宽度效应对自举电流驱动项的削弱则加剧。这意味着磁岛转动方向不同时,此沿力线电流能显著增大或减弱离子香蕉轨道宽度效应对自举电流驱动项的削弱作用。     

反转岛附近原子核奇特性质研究进展

反转岛附近原子核奇特性质的研究是当前核物理研究的热点。 首先简要回顾和介绍了反转岛附近原子核奇特性质的实验进展, 然后介绍了对这些奇特核性质的理论研究进展。 主要包括相对论平均场模型、 壳模型、 Hartree Fock模型和宏观 微观模型在该区域的发展和研究结果。 重点介绍了宏观 微观模型在反转岛附近原子核奇特性质研究中的进展。 此外, 还分析和比较了各种理论模型在描述反转岛附近原子核性质上取得的成功和模型之间的差异。     

原子荧光光谱法研究贝壳堤岛贝壳沙中As的空间分布特征

用原子荧光光谱法测定了贝壳沙中As元素含量,研究了As在黄河三角洲贝壳堤岛贝壳沙中的空间分布规律,分析了贝壳沙中As与其他营养元素的相关性,并对影响其含量与空间分布的因素进行探讨。结果表明：贝壳沙样品中As的含量范围为0.78～8.76 mg·kg-1,平均值为3.11 mg·kg-1,整体上处于清洁的水平。贝壳沙中As含量有随剖面深度增加而增大的趋势,贝壳沙粒径大小也影响贝壳沙中As的含量,贝壳沙粒径越小,As含量越高,且不同粒径贝壳沙中As含量差异显著(p≤0.05)。贝壳沙中As与全磷(total phosphor,TP)和全钾(total potassium,TK)以及Cu, Zn, Mn均具有极显著的正相关关系,与全氮(total nitrogen,TN)和Fe的相关性不显著。综合分析认为,贝壳沙中As主要来自于风化后的贝壳沙对环境中As元素的吸附与固定而非贝壳形成过程中对该元素的富集作用。     

Si衬底上生长的铁硅化合物结构和取向分析

采用分子束外延法分别在650-920 ℃的Si（110）和920 ℃的Si（111）衬底表面生长出铁的硅化物纳米结构,并主要分析了920 ℃高温下纳米结构的形貌、组成相及其与Si 衬底的取向关系. 扫描隧道显微镜（STM）研究表明,920 ℃高温下,Si（110）衬底上生长的铁硅化合物完全以纳米线的形式存在,且其尺寸远大于650 ℃低温下外延生长的纳米线尺寸;Si（111）衬底上生长出三维岛和薄膜两种形貌的铁硅化合物,其中三维岛具有金属特性且直径约300 nm、高约155 nm,薄膜厚度约2 nm. 电子背散射衍射研究表明920 ℃高温下Si（110）衬底上生长的纳米线仅以β-FeSi₂的形式存在,且β-FeSi₂相与衬底之间存在唯一的取向关系：β-FeSi₂（101）//Si（111）;β-FeSi₂ [010]//Si[110];Si（111）衬底上生长的三维岛由六方晶系的Fe₂Si 相组成,Fe₂Si 属于164 空间群,晶胞常数为a=0.405 nm,c=0.509 nm;与衬底之间的取向关系为Fe₂Si（001）∥Si（111）和Fe₂Si[120]//Si[112].     

Fabrication and Patterning of Submierometer-Thick Optical Polarizing Films for 800 nm Using Stretched Silver Island Multilayers

Stretched silver island multilayers have been investigated for patterned optical polarizers for the wavelength of 800 nm. Submicrometer-thick optical polarizing films are fabricated by stretching periodic multilayers consisting of silver island layers and Pyrex layers at the temperature of 660°C. As the optical anisotropy of the optical polarizing film is lost by heating at a temperature higher than the stretching temperature, the fine non-polarizing areas can be deliberately and easily formed on the optical polarizing film by laser irradiation with high power density. We have successfully formed various non-polarizing areas on the optical polarizing film with a 1 W-class carbon dioxide laser. The demonstrated fabricating techniques of deliberately patterned optical polarizing films should be useful for novel optical computing and sensing devices.     

The general properties of the spherical vortices (SV) ofn-TH order and the chaotic phenomena and of the ordered structures of the SV of 3RD order

The general properties of the spherical vortices (SV) of n-th order are discussed in this paper. Numerical calculations are carried out in the case of n=3. We find out some interesting phenomena concerning the chaotic regions and ordered islands on the Poincaré sections. Interpretations of these phenomena are also given. Project supported by the National Basic Research (Nonlinear Science) Foundation of China     

Improved fluorescent assay sensitivity using silver island films: Fluorescein isothiocyanate-labeled albumin as an example

We have studied enhancement of the fluorescence of fluorescein isothiocyanate (FITC), bound to albumin and near an annealed silver island film, as a function of the distance between the protein molecules and the metal. As the intermediate spacer layer between the albumin and the silver substrate, we used multilayer films based on polyelectrolytes. The maximum nine-fold enhancement coefficient for the fluorescence of FITC corresponds to a thickness of the intermediate layer of ≈4 nm, or three layers of the polyelectrolyte. In this case, we observe a significant decrease in the average photoluminescence decay time for the label near the silver film compared with a dielectric medium. __________ Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 73, No. 6, pp. 797–800, November–December, 2006.     

小腿皮神经伴行血管蒂逆行岛状皮瓣的解剖与设计

研究小腿皮神经伴行血管皮瓣的血供方式,并设计其逆行岛状皮瓣供临床参考应用.对30侧成人下肢标本经股动脉加压灌注红色乳胶后进行解剖观测.腓浅神经、腓肠神经及隐神经均有主要伴行动脉营养,并与其他动脉皮穿支吻合营养相应区域的皮肤.根据小腿皮神经伴行血管设计的逆行岛状皮瓣血供可靠,并为沿皮神经轴设计长皮瓣提供了可能.     

胃癌细胞MGC803中LTF基因的表达及其启动子甲基化相关性研究

目的 检测胃癌细胞株MGC803内乳铁蛋白（LTF）基因的甲基化和表达情况,探讨LTF的DNA 启动子区甲基化异常 与其在胃癌内表达的相关性。方法 用亚硫酸氢盐测序PCR 方法检测MGC803 启动子区甲基化状态,使用real-time PCR 和Western blot 分别检测LTF 在MGC803内的mRNA 和蛋白表达水平。同时使用去甲基化剂5-aza-CdR 处理胃癌细胞株,观察给药前后的DNA 甲基化状态和mRNA 表达情况。结果 MGC803 启动子甲基化率达59.8%,使用5-aza-CdR 处理的两组（2滋mol/L组和10滋mol/L组）和空白对照组甲基化率差异、LTF 的mRNA表达差异均有统计学意义（均P＜0.05）,并且随着MGC803启动子甲基化程度的下降,其mRNA 和蛋白表达增加;而不同浓度药物处理组间差异均无统计学意义（均P＞0.05）。结论 LTF 基因在胃癌细胞株MGC803 内表现为较高甲基化状态,而且LTF的表达和其启动子区甲基化情况相关,使用去甲基化剂能逆转DNA 的甲基化情况从而使其mRNA 重新表达。     

Migration-coalescence of Nanoparticles During Deposition of Au,Ag, Cu,and GaAs on Amorphous SiO2

Nanoparticles formed during the initial period of film growth can migrate, coalesce, and may also melt. Nanoparticles of Au, Ag, Cu, and GaAs ranging from 1 to 15nm in diameter were sputter-deposited on amorphous SiO₂ (a-SiO₂). Transmission electron microscopy was used to analyze the time-dependent change of the dispersion of particles on a thin film. The number density of nanoparticles was nearly constant during the deposition of Ag. For Au, Cu, and GaAs, however, the number density decreased with time during the early deposition period. For example, for Au the number density decreased from 2.8×10¹⁶m^–2 (surface coverage ratio of 0.08) to 1.8×10¹⁶m^–2 (surface coverage ratio of 0.14). The surface coverage increased because the particle size increased as the number density decreased. This decrease suggests that migration followed by coalescence occurred. For Au, although we found evidence of migration of 2-nm particles at 500°C, the migration rate was too slow to account for the results from the deposition experiments. These observations indicate an autocatalytic mechanism that migration followed by coalescence liberates energy by the formation of chemical bonds, heats the coalesced particles, and enhances further migration. The strong dependence of the structure of nanoparticle dispersions on the deposition rate is a direct consequence of the deposition mechanism, which is a nonlinear, kinetically-controlled process.