共查询到19条相似文献,搜索用时 187 毫秒
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以固态离子学方法制备的宏观长银(Ag)纳米线簇为基础,采用气-固反应法制备出宏观长硫化银(Ag2S)纳米线簇.利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、能量色散谱(EDS)和X射线光电子能谱(XPS)等手段对样品形貌和成分进行表征.将厘米长的Ag2S纳米线簇两端涂敷金胶作为电极,并与外电路连接.在不同温度或采用不同波长的光束辐照下,测试了样品的输运性质.无光照时,在144—380 K的温度范围内,样品的电导随温度上升而非线性增大.室温下,Ag关键词:
硫化银纳米线
温度电导
光电导 相似文献
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用磁控溅射技术制备不同调幅波长 (L) 的W(Mo)/Cu纳米多层膜,所制膜系在60 keV氦离子 (He+) 辐照条件下注入不同剂量: 0, 1×1017 He+/cm2, 5×1017 He+/cm2. 用X射线衍射仪 (XRD) 和高分辨透射电子显微镜(TEM)表征W(Mo)/Cu纳米多层膜辐照前后微观结构. 研究结果表明: 1) He+离子轰击引起温升效应是导致沉积态亚稳相β-W 转变成稳态 α-W相的主因, 而与调幅波长无明确关联; 2) 纳米多层结构中W(Mo) 和Cu膜显现出的辐照耐受性与调幅波长相关, 调幅波长越小, 抗He+的辐照性能越强; 3) 在5×1017 He+/cm2注入条件下, 观察到He团簇/泡在纳米结构W(Mo) 和Cu膜中的积聚行为存在明显差异: 在W (Mo) 膜中He团簇/泡的分布与晶粒取向相关, He团簇/泡倾向于沿W (211) 晶面分布; 而Cu膜非晶化且He团簇/泡在其体内呈均匀分布.
关键词:
W(Mo)/Cu纳米多层膜
+辐照')" href="#">He+辐照
He团簇/泡
相转变 相似文献
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天然方解石的定代和顺磁共振研究 总被引:1,自引:0,他引:1
用ESR分析了天然方解石(CaCO3)中的杂质Mn2+离子和天然顺磁缺陷的性质。有关谱的理论计算基本和实验结果一致.解释了热处理和辐照样品出现的一些实验现象,最后提出了如何克服干扰解决含有一些杂质Mn2+离子样品的定代问题。 相似文献
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Surface modification and smoothing of patterned surfaces with gas cluster ion beams were studied. In this work, line and space patterns having various intervals and depths were created on amorphous carbon films by focused Ga+ ion beams, and subsequently, Ar GCIB irradiations on the pattern were performed. When the acceleration voltage of Ar cluster ions was 20 kV, the grooves, whose interval was below 200 nm, were planarized. However, it required much higher ion dose for wider interval of patterns. It is estimated that the distance of lateral motions induced by one cluster ion impact defines the spatial wavelength dependence of smoothing. 相似文献
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Exact solutions of Maxwell's equations describing the lightwave
through 3-layer-structured cylindrical waveguide are obtained and
the mode field diameter and nonlinear coefficient of air-core
nanowires (ACNWs) are numerically calculated. The simulation results
show that ACNWs offer some unique optical properties, such as tight
field confining ability and extremely high nonlinearity. At a
certain wavelength and air core radius, we optimize the waveguide
design to maximize the nonlinear coefficient and minimize the mode
field diameter. Our results show that the ACNWs may be powerful
potential tools for novel micro-photonic devices in the near future. 相似文献
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S. Miro J. M. Costantini J. F. Bardeau D. Chateigner F. Studer E. Balanzat 《Journal of Raman spectroscopy : JRS》2011,42(11):2036-2041
Raman spectroscopy was used to study the radiation damage of fluorapatite single crystals and sinters. Krypton and iodine ion irradiations were performed at high energies (∼1 MeV amu−1) for fluences ranging between 1 × 1011 and 5 × 1013 cm−2. Evolution of the symmetric stretching mode of the PO43− tetrahedral building blocks (strongest Raman mode observed at 965 cm−1) versus ion fluence was investigated. After irradiation, this peak decreases in intensity and a second broader peak appears at lower wavenumber. The well‐resolved peak has been assigned to the crystalline phase, and the broader one to the amorphous phase. The integrated intensity ratios of these two peaks versus fluence are in good agreement with the damage fractions determined by X‐ray diffraction (XRD). Fits of the amorphous fraction versus fluence show that the amorphization mechanisms is dominated by a single‐impact process for iodine ions and by a double‐impact process for krypton ions in the case of single crystals and sinters. For both irradiations, complete amorphization could not be obtained. The amorphous fraction saturates at a maximum value of 88% for sinters and 72% for single crystals. This is attributed to a recrystallization effect which is more important in single crystals than in sinters. For both types of samples, the crystalline peak shifts slightly to a lower wavenumber with fluence, and then shifts back to its initial value for an amorphous fraction larger than 60%. This feature is attributed to a stress relaxation, as shown in the XRD data, which is accompanied by a decrease of the crystalline peak full‐width at half‐maximum. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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X.B. Yan T. Xu G. Chen X.B. Wang H.W. Liu S.R. Yang 《Applied Physics A: Materials Science & Processing》2005,81(1):197-203
Amorphous hydrogenated carbon (aC:H) films containing Au nanoparticles have been successfully prepared by heat-treatment of the precursors including poly(phenylcarbyne) polymer and HAuCl4 at 600 °C in Ar atmosphere. The microstructure and morphology of the obtained films were investigated by means of Raman, XPS, XRD, TEM, and AFM. The sheet resistivity of the films was measured by a four-point probe method. Moreover, a ball-on-disc test was employed to obtain information about the frictional properties and sliding wear resistance of the films. The results show that heat-treatment of the precursors at 600 °C causes the change of the polymer into amorphous hydrogenated carbon phase, and the reduction of AuCl4- anions into zero-valence Au. All of the AuaC:H films exhibit smooth morphologies, with the RMS roughness smaller than 0.80 nm. Au nanoparticles are well dispersed in the amorphous carbon matrix, with size ranging from several to tens of nanometers, and the particle size increases with increasing gold content. The incorporation of Au in the carbon matrix can drastically decrease the resistivity and the resistivity of composite films gradually decreases with increasing Au concentration. AuaC:H films with the Au concentration of 2% and 4% show much better friction-reduction and wear-resistance than aC:H film. PACS 81.15.Np; 81.07.-b; 81.40.Pq 相似文献
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Han Liang Chen XianYang Li Wang YanwuWang Xiaoyan Zhao Yuqing 《Applied Surface Science》2011,257(15):6945-6951
The tetrahedral amorphous carbon (ta-C) films with more than 80% sp3 fraction firstly were deposited by filtered cathode vacuum arc (FCVA) technique. Then the energetic nitrogen (N) ion was used to bombard the ta-C films to fabricate nitrogenated tetrahedral amorphous carbon (ta-C:N) films. The composition and structure of the films were analyzed by visible Raman spectrum and X-ray photoelectron spectroscopy (XPS). The result shows that the bombardment of energetic nitrogen ions can induce the formation of CN bonds, the conversion of C-C bonds to CC bonds, and the increase of size of sp2 cluster. The CN bonds are made of CN bonds and C-N bonds. The content of CN bonds increases with the increment of N ion bombardment energy, but the content of C-N bonds is inversely proportional to the increment of nitrogen ion energy. In addition, C≡N bonds are not existed in the films. By the investigation of AFM (atom force microscopy), the RMS (root mean square) of surface roughness of the ta-C film is about 0.21 nm. When the bombarding energy of N ion is 1000 eV, the RMS of surface roughness of the ta-C:N film decreases from 0.21 to 0.18 nm. But along with the increment of the N ion energy ranging from 1400 to 2200 eV again, the RMS of surface roughness of the ta-C:N film increases from 0.19 to 0.33 nm. 相似文献
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L. Torrisi L. Silipigni V. Havranek M. Cutroneo A. Torrisi G. Salvato 《辐射效应与固体损伤》2019,174(11-12):973-984
ABSTRACTReduced graphene oxide (rGO) films can be employed as ion strippers in an accelerator. They show some advantages with respect to the graphite foils, due to their high thermal and electrical conductivity, low density, high mechanical resistance and high stability. Thin graphene oxide (GO) films with a sub-micron thickness have been synthesized and transformed into reduced GO (rGO) by ion beam irradiations. Physical characterizations of the pristine and ion irradiated GO films have been performed. Measurements of stripping efficiency have been carried out by using helium, lithium, carbon and oxygen ion beams. The rGO stripper films demonstrate a significantly high charge production, comparable to that of the graphite films but with the advantage of a longer lifetime. 相似文献
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Amorphous-carbon (a-C) films were deposited on a single-crystal silicon substrate by vacuum vapor deposition system and these amorphous carbon films were implanted with 110 keV C+ at fluences of 1 × 1017 ions/cm2. The effect of ion mixing on the surface morphology, friction behavior and adhesion strengths of amorphous carbon films was examined making use of atomic force microscopy (AFM), ball-on-disk reciprocating friction tester, nano-indentation system and scanning electron microscope (SEM). The changes in chemical composition and structure were investigated by using X-ray photoelectron spectroscopy (XPS). The results show that the anti-wear life and adhesion of amorphous carbon films on the Si substrates were significantly increased by C ion implantation. The SiC chemical bonding across the interface plays a key role in the increase of adhesion strength and the anti-wear life of amorphous carbon film. The friction and wear mechanisms of amorphous carbon film under dry friction condition were also discussed. 相似文献
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Summary The phase transition of amorphous to single-crystal silicon has been investigated not only by conventional heating in a furnace
but under direct-energy processes like pulsed-laser and ion beam irradiation. The first method allows the experimental determination
of the free-energy-temperature diagram for amorphous, liquid and crystalline silicon. Due to the very fast heating and cooling
the amorphous-to-liquid transition can be investigated in both directions. Ion beam irradiation induces either a layer-by-layer
amorphization or crystallization by the movement of the initial α-Si/c-Si interface according to the substrate temperature.
The two processes are governed by different types of defects created by the beam in the amorphous and in the crystalline side
of the interface. The existence of a native-oxide layer at the interface between single crystal and deposited layer retards
the ion beam crystallization until oxygen atoms are dispersed by beam mixing in the matrix. A recent alternative way of crystallizing
deposited layers is by short high-temperature anneals obtained by incoherent-light irradiations. In this case the rupture
of the native-oxide layer is achieved by the agglomeration of oxide into beads, thus allowing the realignment. This technique
appears to be particularly promising for several technological applications.
In honour of Prof. Fausto Fumi on the occasion of his retirement from teaching. 相似文献