景德镇五代瓷器组成配方的EDXRF分析

景德镇早期制瓷工艺一直是学术界所关注的焦点问题之一。采用能量色散X射线荧光法分析了景德镇五代时期湘湖窑出土白瓷和青瓷样品的胎釉元素组成,并据此探讨其原料和配方。研究表明,五代时期景德镇湘湖窑白瓷胎体所用原料为瓷石,而青瓷瓷胎应是采用瓷石配以紫金土的二元配方;白瓷和青瓷瓷釉皆使用釉果加釉灰的配方,且青瓷瓷釉配方中釉灰的用量高于白瓷瓷釉。     

巩窑唐代早期白瓷的EDXRF线扫描分析

具有悠久瓷器生产历史的巩窑,是我国古代北方烧制白瓷的3个代表性窑口之一。在唐代早期,为了掩盖瓷胎表面的粗糙状态和较深的胎体颜色,提高瓷器的质量和白度,巩窑白瓷在胎的表面施加了一层装饰层——化妆土。用能量色散X射线探针技术对这些白瓷碎片的剖面进行了主要化学成分的线扫描分析,结果表明： 巩窑唐代早期白瓷的化妆土使用了不同的原料,与光学显微镜下观察到的现象相符合。另外,白瓷釉可能是加有草木灰的钙釉。     

安徽繁昌柯家冲窑青白瓷釉化学组成及其制釉工艺来源研究

为了解繁昌柯家冲窑青白瓷釉化学组成特征及其演变过程,并探索我国南方早期青白釉的工艺技术来源,本文运用能量色散X射线荧光光谱法(EDXRF)分析了柯家冲窑五代至北宋中期不同阶段青白瓷釉的化学组成,并将分析结果与同时期北方定窑白瓷釉及南方越窑青瓷釉化学组成进行了综合对比研究。结果显示,繁昌柯家冲窑青白釉化学组成在北宋中期时发生了明显变化,其中尤以SiO₂含量的下降和CaO含量的上升最为明显,着色元素Fe,Mn,Ti的氧化物含量自五代时期至北宋中期变化幅度很小,繁昌柯家冲窑青白釉釉色由偏白向偏青转变的原因可能与该窑瓷器胎色的不断加深有关。此外,主成分分析及具有相似功能特性的元素组合对比分析结果显示,繁昌柯家冲窑青白瓷釉的化学组成与北方定窑白瓷釉较为接近,其釉料配方工艺可能来源于同时期我国北方地区以定窑为代表的白瓷窑场。本文研究结果对了解我国早期青白瓷釉的化学组成特征及晚唐五代时期南、北方制瓷工艺技术交流问题等有重要学术价值。     

历代定窑白瓷的EDXRF和XAFS分析

定窑是我国宋代五大名窑中唯一以生产白瓷而闻名于世的窑厂,其高超的刻印花纹技术及首创的支圈覆烧工艺,对国内外许多窑场产生了深远的影响。采用(energy dispersive X-ray fluorescence, EDXRF)探索了历代定窑白瓷的组成配方,并采用X射线吸收精细结构(XAFS)法分析了瓷釉中Fe元素的价态,以探讨定窑白瓷的相关烧制工艺。研究发现,定窑白瓷瓷胎具有典型北方瓷器“高铝低硅”的特征,并在瓷胎中特意添加了富含CaO的矿物原料,对瓷胎的烧结有一定的促进作用。瓷胎中的TiO₂应主要是高岭土原料中的杂质。定窑白瓷瓷釉具有“高钙高镁”特征,基本属于钙镁釉或钙镁碱釉。其瓷釉配方中应含有一定量的白云石或滑石。瓷釉中K₂O的含量逐步增加,反映了定窑瓷釉由钙镁釉向钙碱釉发展演变的过程。此外,根据瓷釉中的Al₂O₃,MnO和P₂O₅等含量的特征,可以推测釉料配方中应添加了草木灰和高岭土。由XAFS分析结果可知,晚唐五代时期定窑白瓷釉中Fe3+比例最高,金代次之,宋代最低,不同时期定窑白瓷皆是在还原气氛中烧成。宋金时期定窑白瓷白中泛黄可能由于燃料煤中富含的硫在燃烧过程中与瓷釉反应,生成Fe-S化合物所致。     

唐三彩烧制工艺的无损分析研究

唐三彩是我国重要的文化遗产,分析其胎体和釉料的化学成分和物相结构对研究其原料特点和烧制工艺具有重要意义。利用微束X射线荧光谱仪和X射线衍射谱仪无损分析陕西醴泉坊窑、河南黄冶窑和陕西省博物馆烧制的现代仿品等唐三彩样品。研究结果表明,醴泉坊窑唐三彩和黄冶窑唐三彩的原料来源于不同类别的黏土。醴泉坊窑和黄冶窑烧制的唐三彩胎料中主要含有大量α-石英(SiO₂, PDF 46-1045)和少量的方石英(SiO₂, PDF 76-0932)等晶相,但醴泉坊窑和黄冶窑烧制的唐三彩胎料中还分别存在少量α-Fe₂O₃(Fe₂O₃, PDF 16-0653)和微量莫来石(3Al₂O₃·2SiO₂, PDF 83-1881)等晶相。这表明二者原料来源和烧制工艺的不同导致其烧成胎料中矿物结构的差异。在唐三彩的釉彩中,着色元素Fe, Cu和Co充分熔融在铅熔剂里,且在黄釉和绿釉的交界处Fe与Cu相互交融。釉彩的XRD谱...     

东门渡窑古陶瓷化学成分与烧制工艺研究

芜湖东门渡窑是古代宣州窑场的早期窑口之一,属古越窑系青瓷;该窑口出产的陶瓷产品器型别具一格,具有鲜明的地域特色.但长期以来,对于东门渡窑瓷器仅仅从其外观推测其工艺特征,对该类瓷器的微观结构特征和配方工艺特点缺乏必要的分析证据.为系统解析东门渡窑古陶瓷的胎、釉化学组成和烧制工艺,运用波长色散X射线荧光光谱法(EDXRF)...     

安徽繁昌窑青白瓷化学组成的WDXRF分析研究

安徽繁昌窑五代时期(AD907-960)创烧青白瓷,是目前已知的我国最早烧造青白瓷的窑场。北宋中期(AD1023-1085)后,繁昌窑迅速衰落,对其衰落原因,目前尚不清楚。文章运用波长色散X射线荧光光谱法(WDXRF)分析了繁昌窑青白瓷胎的化学组成,结果显示北宋中期时繁昌窑瓷胎的主微元素化学组成均发生了较为明显的改变。结合中子活化分析及瓷釉研究的结果来看,这种改变应是因其制瓷原料或胎料配方发生变化引起的。同时,这种瓷胎化学组成的变化也是导致繁昌窑北宋中期产品质量下降并最终迅速衰落的主要原因。     

中国古代南方白瓷的组成特征研究

景德镇窑和德化窑是南方白釉瓷窑口中最具有代表性的两个窑口。该文利用能量色散X射线荧光光谱分析仪,对30件宋、元、明时期的德化白瓷以及元代景德镇枢府白瓷样品进行了测试,并从时空角度对比分析了不同白瓷样品胎釉的组成特征。结果表明,景德镇枢府白瓷胎釉组成铁含量均明显偏高,而德化白瓷胎釉组成中的钾含量均明显偏高,且随着时间发展具有上升趋势,这应是德化雕塑白瓷异军突起的主要原因。     

用多元统计分析研究黄冶窑白瓷的原料特征

黄冶窑文化内涵丰富,其创烧于隋,兴盛于唐代中期,停烧于唐代晚期。为探讨不同时期黄冶窑白瓷的胎料来源和釉料配方是否相同,选取黄冶窑隋、早唐、中唐、晚唐四个时期的80个白瓷样品,利用质子激发X射线荧光分析(PIXE)测定各样品胎、釉中9种化学成分(Na₂O、MgO、Al₂O₃、SiO₂、P₂O₅、K₂O、CaO、TiO₂、Fe₂O₃)的含量,用多元统计分析中的Fisher判别分析处理PIXE数据,并计算各样品釉的木灰釉式系数b来划分瓷釉类型。结果表明:黄冶窑四个时期的胎料取自同一或相近的地点,都是就地取材;四个时期的釉料配方比较相似,而四期白瓷的釉料配方最为稳定,且与二期釉料配方最相似,而与一期釉料配方已有明显不同;黄冶窑白瓷釉大部分为钙釉,存在少量钙碱釉和碱钙釉。     

不同处理工艺钢渣的X射线衍射和X射线荧光光谱分析及其活性指数预测模型

以不同处理工艺钢渣,即转炉热泼渣、转炉滚筒渣、铸余渣、铁水脱硫渣、电炉热泼渣和电炉滚筒渣作为研究对象。利用X射线衍射仪和X射线荧光光谱分析仪研究钢渣的化学成分与物相组成。利用BP神经网络模型建立钢渣活性指数预测模型,研究化学成分、物相组成与活性的关系。结果表明： 钢渣的处理工艺不同,其化学成分与物相组成存在明显差异;钢渣活性指数预测模型具有良好的符合性,即相对误差为2.42%和-2.54%,能充分反映输入层与输出层之间的映射关系。     

Silicon Photonics Rectangular Universal Interferometer

Universal multiport photonic interferometers that can implement any arbitrary unitary transformation between input and output optical modes are essential to support advanced optical functions. Integrated versions of these components can be implemented by means of either a fixed triangular or a fixed rectangular arrangement of the same components. We propose the implementation of a fixed rectangular universal interferometer using a reconfigurable hexagonal waveguide mesh circuit. A suitable adaptation synthesis algorithm tailored to this mesh configuration is provided and the experimental demonstration of a rectangular multiport interferometer by means of a fabricated silicon photonics chip is reported. The 7‐hexagonal cell chip can implement 2 × 2, 3 × 3 and 4 × 4 arbitrary unitary transformations. The proposed hexagonal waveguide mesh operates in a similar way as a Field Programmable Gate Array (FPGA) in electronics. We believe that this work represents an important step‐forward towards fully programmable and integrable multiport interferometers.     

Focal waveforms with tunable carrier frequency using dispersive aperturing

We introduce the concept of dispersive aperturing involving a beam truncation by hard-edge apertures where diameter of the processed beam changes upon frequency. Applied to focused waves, this procedure transforms power spectra at the focal point (and the surroundings). Waveforms at focus conserve pulse duration but carrier frequency may be altered substantially. In principle, some degrees of freedom allow carrier-frequency tuning at convenience.     

Augmented low index waveguide for confining light in low index media

Guiding light in the low index region of a high refractive index contrast waveguide can be beneficial for many applications including sensing, nonlinear optics and electro‐optics. Existing methods to achieve this goal suffer from fabrication complexity, large loss, or poor optical confinement. We propose a simple structure to achieve a significant enhancement of light confinement in the low index medium. We explain the guiding principle of this structure using geometrical optics, and suggest a number of applications where this guiding structure can provide significant performance benefits. The combination of simplicity, ease of fabrication, and good confinement makes this waveguide an attractive choice for a wide range of applications. To illustrate this, we consider the integration of a nonlinear polymer with a silicon photonic waveguide, and show that significantly better performance with an easier fabrication process can be achieved using this new scheme.

     

Quantum coherent versus classical coherent light

The paper shows that the Wigner distribution function of quantum optical coherent states, or of a superposition of such states, can be produced and measured with a classical optical set-up using classical coherent light fields. This measurement cannot be done directly in quantum optics since the quantum phase space variables correspond to non-commuting operators. As an example, the Wigner distribution function of Schrödinger cat states of light has been measured. It is also shown that the possibility of measuring the Wigner distribution function of quantum coherent states with classical coherent fields is unique in the sense that it cannot be extended to other quantum states, not even to the incoherent limit of the superposition of coherent states.     

Programming matrix optics into Mathematica

The various non-linear transformations incurred by the rays in an optical system can be modelled by matrix products up to any desired order of approximation. Mathematica software has been used to find the appropriate matrix coefficients for the straight path transformation and for the transformations induced by conical surfaces, both direction change and position offset. The same software package was programmed to model optical systems in seventh order. A Petzval lens was used to exemplify the modelling power of the program.     

Quantum noise limits to terabaud communications

From a general model of fiber optics, we investigate the physical limits of soliton-based terabaud communication systems. In particular we consider Raman and initial quantum noise effects which are often neglected in fiber communications. Simulations of the position diffusion in dark and bright solitons show that these effects become increasingly important at short pulse durations, even over kilometer-scale distances. We also obtain an approximate analytic theory in agreement with numerical simulations, which shows that the Raman effects exceed the Gordon-Haus jitter for sub-picosecond pulses.     

Cloak an illusion

An illusion counter-part displays the same scattering far-field pattern as that of a real object. In this paper, for the first time, we demonstrate that such an unreal illusion can be cloaked by an external cloak. This phenomenon shall be called ??cloak an illusion??. Numerical simulations were performed to demonstrate such a phenomenon.     

非线性对称平板光波导TE模色散特性的近似计算

本文利用微扰法,导出了克尔型非线性对称平板光波导TE模传播常数的近似计算公式。结果表明,本文公式得到的结果与精确结果吻合得很好。     

非线性光学与光学教学

在简要介绍非线性光学的基础上说明非线性光学不仅是强光光学。在低功率激光、非相干光下,仍存在丰富多彩的非线性光学现象。因此在有关的光学课程中应改进其非线性光学部分的教学。     

Retina imaging system with adaptive optics for the eye with or without myopia

An adaptive optics system for the retina imaging is introduced in the paper. It can be applied to the eye with myopia from 0 to 6 diopters without any adjustment of the system. A high-resolution liquid crystal on silicon (LCOS) device is used as the wave-front corrector. The aberration is detected by a Shack-Harmann wave-front sensor (HASO) that has a Root Mean Square (RMS) measurement accuracy of λ/100 (λ = 0.633 μm). And an equivalent scale model eye is constructed with a short focal length lens (∼18 mm) and a diffuse reflection object (paper screen) as the retina. By changing the distance between the paper screen and the lens, we simulate the eye with larger diopters than 5 and the depth of field. The RMS value both before and after correction is obtained by the wave-front sensor. After correction, the system reaches the diffraction-limited resolution approximately 230 cycles/mm at the object space. It is proved that if the myopia is smaller than 6 diopters and the depth of field is between −40 and +50 mm, the system can correct the aberration very well.