Photoreduction of Ag+ in aluminoborate glasses induced by irradiation of a femtosecond laser

We report on photoreduction of Ag+ in aluminoborate glasses induced by irradiation of a femtosecond laser. Novel fluorescence was observed in the femtosecond laser irradiated glass when excited by a 365 nm ultraviolet lamp. Optical absorption, emission, and electron spin resonance spectra of the glass samples demonstrated that after the laser irradiation, portions of silver ions near the focused part of the laser beam inside the glass were reduced to silver atoms, which resulted in the formation of the characteristic fluorescence. The observed phenomenon may have promising applications in the fabrication of functional optical devices.

The study on the interface adhesion comparison of the MgF2, Al2O3, SiO2 and Ag thin films

Adhesion between the interface of pure silver thin film and three kinds of low refractive index coatings MgF2, Al2O3, SiO2 were compared in this article. The results indicated that the adhesion of Al2O3 and Ag was evidently superior to that of MgF2 and Ag, and the adhesion of MgF2 and Ag was evidently superior to that Of SiO2 and Ag. Reasons were analyzed accordingly. On the other hand, we compared the effect on the optical characteristic of Ag film when these three kinds of films were used as protective coatings and enhanced coatings. Considering the difference of the adhesion between Ag and MgF2, Al2O3, SiO2, suited uses are given for each other. © 2004 Elsevier B.V. All rights reserved.

Influence of Cr interlayer on the structure and optical properties of Ag films on glass substrate by magnetron sputtering

Optical properties and microstructure of Ag film on glass substrate with Cr intermediate layer were studied by using spectrophotometer and XRD. The spectra results showed that introducing Cr intermediate layer reduced the surface roughness and promoted the reflectivity of Ag film. The XRD analysis showed that the crystalline grains increased and the stress decreased. The adhesion was also improved by using the tape test method. (c) 2006 Published by Elsevier B.V.

Effect of alumina and chromium interlayers on microstructures and optical properties of thin Ag films on glass substrates

Effects of alumina and chromium interlayers on the microstructure and optical properties of thin Ag films are investigated by using spectrophotometry, x-ray diffraction and AFM. The characteristics of Ag films in Ag/glass, Ag/Al2O3/glass and Ag/Cr/glass stacks are analysed. The results indicate that the insertion of an Al2O3 or Cr layer decreases the grains and influences the reflectance of Ag films. The reflectance of the Ag film can be increased by controlling the thickness of alumina interlayer. The stability of Ag films is improved and the adhesion of Ag films on glass substrates is enhanced by alumina as an interlayer.

Structural and optical properties of nanostructured TiO2 thin films fabricated by glancing angle deposition

TiO2 films deposited by electron beam evaporation with glancing angle deposition (GLAD) technique were reported. The influence of flux angle on the surface morphology and the microstructure was investigated by scanning electron microscopy. The GLAD TiO2 films are anisotropy with highly orientated nanostructure of the slanted columns. With the increase of flux angle, refractive index and packing density decrease. This is caused by the shadowing effect dominating film growth. The anisotropic structure of TiO2 films results in optical birefringence, which reaches its maximum at the flux angle alpha = 65 degrees. The maximum birefringence of GLAD TiO2 films is higher than that of common bulk materials. It is suggested that glancing angle deposition may offer an effective method to obtain tailorable refractive index and birefringence in a large continuous range. (c) 2006 Elsevier B.V. All rights reserved.

Preparation and characterization of nanostructured ZrO2 thin films by glancing angle deposition

ZrO2 films were prepared by electron beam evaporation with glancing angle deposition (GLAD) technique. The as-deposition and annealed ZrO2 films are all amorphous, different from that deposited at normal incidence. Due to the shadowing effect, a highly orientated structure composed of slanted columns formed, and the obtained films became the mixture of slanted columns and voids. The relationship among the effective refractive index, packing density and flux incident angle was investigated. The refractive index and packing density of ZrO2 films decrease with the increase of the incident angle. The in-plane birefringence of GLAD ZrO2 films was calculated. At the packing density of 0.576, the maximum birefringence is 0.037. (c) 2006 Elsevier B.V. All rights reserved.

Al2O3和Cr过渡层对Ag膜光学性质及其附着力的影响

研究了在玻璃基底上镀制Al2O3和Cr过渡层对Ag膜反射率及附着力的影响.分光光度计测试了Ag膜的反射率,结果表明,与Cr过渡层相比,Al2O3过渡层对Ag膜反射率的降低相对较小;而且,随着Al2O3厚度的增加,Ag膜的反射率先增大后减小.XRD与AES测试表明,引入Al2O3或Cr可明显细化Ag晶粒,减弱Ag膜（111）织构;Al2O3作过渡层时,Al原子向Ag层中扩散显著;而Cr作过渡层时,只有少量Cr原子扩散进入Ag层.因此,Al2O3作过渡层能显著增强薄膜与玻璃基体之间的附着力.

Distribution of rDNA in the nucleus of Giardia lamblia - Detection by Ag-I silver stain

OBJECTIVE: To determine whether rDNA of Giardia lamblia forms a nucleolus organizer region (NOR)-like structure and is in a very primitive state. STUDY DESIGN: G lamblia was used as the experimental animal, with Euglena gracilis as the control. The distribution was demonstrated indirectly by the modified Ag-I silver technique, which can specifically indicate the NOR under both light and electron microscopes. RESULTS: In the ultrathin sections of silver-stained Euglena cells, all the silver grains were concentrated in the fibrosa of the nucleolus, while no grains found in the cytoplasm, nucleoplasm, condensed chromosomes or pars granulosa of the nucleus. In the silver-stained Giardia cells, no nucleolus was found; a few silver grains were scattered in the nucleus but were not concentrated in any specific region. CONCLUSION: The distribution of silver grains in G lamblia showed that the transcription of rDNA occurs inside the nucleus, though no nucleolus is present. It is possible that chromosomes are in a very primitive state in diplomonad cells; as each chromosome has few prRNA genes, the transcription is independent of a nucleolus. These results imply that the rDNA of Giardia does not form a NOR-like structure and seems to represent a very primitive state in the evolution of the nucleolus.

团花锦蛇、绿锦蛇和三索锦蛇的核型及Ag-NORs

报道了锦蛇属团花锦蛇( E. davidi) 、绿锦蛇( E. prasina) 和三索锦蛇( E. radiata) 3 个种的核型和Ag - NORs ,团花锦蛇的核型2 n = 36 (8V + 6sV + 2I + 20M) ;绿锦蛇的核型2 n = 36 (7V + 7sV + 2I + 20m) ,三索锦蛇的 核型2 n = 40 (6V + 3sV + 2sI + 5I + 24m) ; ①团花锦蛇和绿锦蛇的染色体数目和结构与此属大多数种的相似, ; ② 此属种类的性染色体为ZW型,绿锦蛇的性染色体为第4 对大染色体,三索锦蛇的为第5 对大染色体,团花锦蛇 由于为雄性,未见染色体异型. ③Ag - NORs 在数目及在染色体上的位置均不相同,团花锦蛇的NORs 在第9 对 染色体上,数目为2 个;绿锦蛇的NORs 在第5 对染色体上,数目为4 个;三索锦蛇的NORs 在第4 对大染色体上, 数目为4 个; ④我们发现三索锦蛇较为特殊,其染色体数目、形态、性染色体的位置和形态及Ag - NORs 均与其 它种类不同. 可能的原因是此物种在核型演化过程中发生过染色体断裂和重排事件,提示三索锦蛇可能是一个 特化的类群. ⑤锦蛇属的种类可分为包括三索锦蛇为特殊的一组的4 个组. 图版1 表2 参18

颈棱蛇核型和Ag-NORs的研究

研究了云南产颈梭蛇的核型和Ag-NORs。其2n=46, 由8对大染色体和15对小染色体组成, 大染色体中NO.6、8为亚中着丝粒染色体, 其余均为端或亚端着丝粒染色体。第4对大型染色体为性染色体, 雌性为ZW型。并对颈棱蛇的分类和进化进行了讨论。

云南龙陵黄山羊的核型及C－带和Ag－NOR_s研究

采用外周血淋巴细胞培养及染色体分带技术，分析了龙陵黄山羊的核型，Ｃ—带和银染核仁组织区（Ａｇ—ＮＯＲ＿ｓ），结果表明：龙陵黄山羊染色体数为２ｎ＝６０，常染色体及Ｘ染色体为端部着丝粒染色体，Ｙ染色体最小，为中部着丝粒染色体。常染色体着丝粒区均显示Ｃ—带，性染色体未显Ｃ—带．雌性银染核仁组织区（Ａｇ—ＮＯＲ＿ｓ）分布于Ｎｏ．１，２，３，４，５，２５号染色体，雄性分布于Ｎｏ．１，２，２５号染色体，显示了性别及分布多态性。研究还发现三种不同的联合（ＡＳＳＯＣＩＡＴＩＯＮ）。