浅析线描类课程的教学改进

线描在中国画的绘画中有着崇高的地位和作用,在充分了解、理解线描艺术的基础上进行线描课程的改进,使学生的功底、技法、综合素养得到进一步的提高.     

注重个性 增强自信心 体验成功

线条是最简便、最直接用于表现形象的绘画手段，自古以来，在中外绘画艺术中始终占有重要地位。绘画从发展的初期，在原始绘画、儿童绘画中，线条就是主要的表现形式；在绘画的成熟阶段写实绘画里，线描也是表现物像的重要手段；现代派画家追求单纯，追求抽象，线条更是不可缺少的语言工具。在美术课线描教学中，注重培养学生个性、自信心和体验成功，对美术教育、素质教育大有裨益。     

论中国画线描艺术的写意与装饰性表现

线描在中国绘画中一直作为造型的主要手段存在与发展,从而形成独特的民族风格。要研究中国绘画艺术的特点,就必须先从"线"的研究开始,而中国绘画中线的写意性与装饰性表现,又是中国传统绘画艺术的重要发展渊源,为此了解和重新认识线描的表现特性,对于研究中国画线描艺术的发展具有十分重要的意义。     

线描艺术探索

阐述了中国绘画艺术中传统线描技法的历史沿革及发展特色,通过具体画面图形的设计介绍了线描技法在连环画创作中的运用.     

基于计算机视觉的自然图像自动线描系统

介绍一种自然图像的自动线描算法,使计算机能模拟人类素描绘画的过程.该系统包括线描提取及线描渲染两步骤.在线描提取过程中,采用一种综合低层及中层视觉信息的边缘检测方法提取线描,在传统边缘检测结果基础上,根据计算机视觉理论对边缘进行精简及连接等处理;在线描渲染过程中,采用尺度、亮度等特征作为渲染画刷的属性,对边缘曲线进行拟合后采用纹理映射等非真实感渲染的方法产生线描图像.实验结果表明:基于计算机视觉理论的自动线描方法切实可行,线描提取结果优于传统边缘检测结果,能很好地体现线描图像的艺术效果.     

谈线描人物画中形的教学

线描人物画是绘画教学中的重要基础课之一,线描人物画教学的意义在于使学生能对人物形象的把握更加准确,对人物结构更加清楚,对人物的艺术表现力更加丰富,这可为以后的绘画学习打下一个坚实的基础.由于学生进校前水平有高低,学生理解能力有差异,在学习过程中会出现各种各样的问题,其中比较普遍和具备代表性的有:对以线造形的方法运用不够熟练和准确;由于过分追求线条本身而失去对整体画面的处理,     

从"十八描"看历代人物画线描的发展进程

线是中国画的主要表现语言,是中国古代传统绘画的主要表现手段,是中国人物画的基础。本文旨在通过对历代优秀艺术家创造的光辉灿烂的线描艺术及其优秀白描作品的论析,以便我们了解人物画线描的发展进程,把握各个历史时期线描的特点,为我们研究古代白描人物画提供一个有益的借鉴。     

马王堆T型帛画的绘画艺术

西汉时期的马王堆T型帛画，是中国传统绘画中的一件艺术瑰宝，纵观整件帛画，无论从写实肖像到浓艳的色彩，还是从线描艺术到构图布局，T型帛画承载着汉代悠久的历史文化，渗透着汉代画工高超的绘画技艺，对中国传统绘画的发展产生了巨大影响。     

素描和油画的特征及与传统中国画的对比

学习素描是为油画打基础的,而传统中国画则是从线描开始。对比油画和传统中国画的表现方法,把素描和油画技法引用到现代陶瓷装饰上来可丰富其装饰内容,增强传统装饰技法的表现力,增强画面的可观性,是中国传统陶瓷装饰与西方绘画语言的有机结合。     

一趣,二实,三放——让孩子们用心绘画

少儿美育教师如何让孩子们从大量技能技巧的灌输里脱颖而出,既学习到更多的美术专业知识,又能够不拘一格地大胆表现呢?最好的方法在于唤醒和鼓舞,实打实地画些线描、写生,提高徒手造型能力,然后应鼓励儿童发散思维,让孩子用绘画表达内心的感受.     

Foliar δ^13C and δ^15N values of C3 plants in the Ethiopia Rift Valley and their environmental controls

The foliar C and N stable isotopic compositions （δ^13C and δ^15N） and the relationships between these compositions and environmental factors of C3 plants in the Ethiopia Rift Valley were investigated. There were three distribution patterns for foliar δ^13C with mean values of -26.7‰±0.4‰, -29.7‰ ±0.6‰ , and -26.9‰± 1.2‰ in cold-moist, temperate-moist, and arid-hot environments, respectively. The δ^15N values ranged from -1.4‰ ±1.7‰ to 14.3‰ ± 0.1‰, with higher values under arid-hot conditions and the lowest values in plants growing at higher altitudes under cold-moist conditions. A strong negative relationship between mean annual precipitation and δ^15N explained more than half of the observed variation in the δ^15N values （r2= 0.54, P 〈 0.001）; a modest positive relationship was also found between δ^15N and temperature （r2 = 0.32, P 〈 0.01）. A weakly positive relationship existed between δ^13C and temperature, and changes in δ^13C values with precipitation and altitude followed quadratic curves. This suggests a shift in the effects of water and heat conditions caused by altitude on carbon isotopic discrimination.     

四元数矩阵方程AXB+CXD=E的M自共轭解

把实数域上的M对称矩阵的概念推广到四元数体上,形成M自共轭矩阵,然后在四元数体上讨论矩阵方程AXB+CXD=E的M自共轭解及其最佳逼近问题.利用四元数矩阵的实分解和复分解,以及M自共轭矩阵的特征结构,借助Kronecker积把约束四元数矩阵方程转化为实数域上的无约束方程,克服了四元数乘法非交换运算的困难,并得到该方程具有M自共轭解的充要条件及其通解表达式.同时在解集非空的条件下,运用矩阵的分块技术及矩阵的拉直算子,获得与预先给定的四元数矩阵有极小Frobenius范数的最佳逼近解.由于M自共轭矩阵是四元数自共轭矩阵的推广,因此所得结果拓展了该方程的结构解类型.     

Synthesis process of Ba-ferrites from α-FeOOH and γ-FeOOH and investigation of magnetic properties

The claviform BaFe₁₂O₁₉ crystals were synthesized by the precipitation-toptactic reaction method using α-FeOOH and γ-FeOOH as raw materials respectively. The synthesis processes of BaFe₁₂O₁₉, studied by XRD, SEM, EDS, FT-IR, and TG-DTA techniques, included preparations of precursor γ and precursor α, formations of α-Fe₂O₃ and BaFe₂O₄, and production of rod-like BaFe₁₂O₁₉ through dehydroxylation of pod-like FeOOH, followed by reactions of α-Fe₂O₃ with BaCO₃ and BaFe₂O₄. The crystallinity of α-Fe₂O₃ and BaCO₃ from precursor α was better than from precursor γ due to the direct dehydroxylation of α-FeOOH, resulting in a lower nucleation rate and better crystallinity of BaFe₂O₄. BaFe₁₂O₁₉ prepared from precursor α showed lower crystallinity and purity with a higher length-diameter ratio than from precursor γ. The VSM results proved that the appearance of final products had an important influence on magnetic properties.     

图的Seidel Laplacian-Estrada指标

设G为简单图,d_i表示顶点v_i的度,G的Seidel Laplacian矩阵S_L(G)是一个对角元为n-1-2d_i,非对角元为±1的实对称矩阵,当顶点v_i和v_j相邻时,(S_L(G))_(ij)=1,否则,(S_L(G))_(ij)=-1。引入并研究了Seidel Laplacian矩阵的Estrada指标,给出了该指标的上、下界,以及它与Seidel Laplacian能量之间的关系。     

Characteristics of lateral heterogeneities with thermal and chemical origins in the pyrolitic lower mantle

The relative changes between shear and compressional velocities (R_SP = ∂ ln V_S/∂ ln V_P), bulk sound and shear velocities (R_CS = ∂ ln V_C/∂ ln V_S), and density versus shear wave velocity (R_ρS = ∂ ln ρ/∂ ln V_S) in response to thermal and chemical variations were investigated for the pyrolitic lower mantle. For heterogeneities with thermal origins, R_SP increases from 1.7 to 2.0 together with R_ρS decreasing from 0.4 to 0.2 and R_CS = ∼0.27 from the top to the bottom of the lower mantle. In comparison, chemical variations (bulk iron or silica contents) are characterized by R_SP < 1.5 and R_CS > 0.5 at lower mantle depths. Negative values of R_ρS and R_CS are indicative of chemical anomalies in the lower mantle, but a combination of thermal and chemical heterogeneities may be required to produce velocity and density anomalies at the magnitudes observed in seismic data. Further refinement of these characteristics requires data on the higher order pressure and temperature derivatives of the elastic moduli of the constituent phases.     

Effects of Yb^3＋ codoping on visible and near infrared emissions of Er^3＋-Yb^3＋ codoped Al2O3 powders by the sol-gel method

The 0.1 mol% Er^3＋ and 0-2 mol% Yb^3＋ codoped Al2O3 powders were prepared by the sol-gel method, and the phase structure, including only two crystalline types of doped Al2O3 phase, γ-（Al,Er, Yb）2O3 and θ-（Al,Er, Yb）2O3, was detected at the sintering temperature of 1000℃. The visible and near infrared emissions properties depended strongly on the Yb^3＋ codoping, and the corresponding maximal peak intensities centered at about 523, 545, 660 and 1533 nm were obtained respectively for the 0.1 mol% Er^3＋ and 0.5 mol% Yb^3＋ codoped Al2O3 powders, which were composed of θ-（Al,Er,Yb）2O3 and a small amount of γ-（Al,Er, Yb）2O3 phases. The two-photon absorption process was responsible for the visible up-conversion emissions, and the one-photon absorption process was involved in the near infrared emissions of the Er^3＋-yb^3＋ codoped Al2O3 powders.     

Operational properties and matrix representations of quantum measures

Denoted by M(A), QM(A) and SQM(A) the sets of all measures, quantum measures and subadditive quantum measures on a σ-algebra A, respectively. We observe that these sets are all positive cones in the real vector space F(A) of all real-valued functions on A and prove that M(A) is a face of SQM(A). It is proved that the product of m grade-1 measures is a grade-m measure. By combining a matrix M _μ to a quantum measure μ on the power set A _n of an n-element set X, it is proved that μ ≪ ν (resp. μ ⊥ ν) if and only if M _μ ≪ M _ν (resp. M _μ M _ν =0). Also, it is shown that two nontrivial measures μ and ν are mutually absolutely continuous if and only if μ·ν∈QM(A _n ). Moreover, the matrices corresponding to quantum measures are characterized. Finally, convergence of a sequence of quantum measures on A _n is introduced and discussed; especially, the Vitali-Hahn-Saks theorem for quantum measures is proved.     

复合添加剂对金属陶瓷惰性阳极导电性的影响

为了改善金属相对陶瓷相的润湿,充分发挥金属相的作用,在合成含10%Ag的Ag/NiFe2O4金属陶瓷过程中引入添加剂TiO2和V2O5,采用粉末冶金法制备Ag/NiFe2O4金属陶瓷惰性阳极.原料NiO,Fe2O3,Ag和微量TiO2,V2O5经混料、成型后在1 250℃下烧结6 h.研究了添加剂TiO2,V2O5对Ag/NiFe2O4金属陶瓷微观形貌以及对试样电导率的影响.研究结果表明,复合添加TiO2,V2O5后金属银在陶瓷相中呈线状分布,EDX分析发现金属相中含有陶瓷相的组成,说明金属相与陶瓷相间的润湿性有所改善;同时试样的电导率有了显著提高.当添加0.5%TiO2,2.0%V2O5时试...     

Comparison study of chitosan/β-cyclodextrin and carboxymethyl chitosan/β-cyclodextrin microspheres

To compare two microspheres of chitosan/β-cyclodextrin and carboxymethyl chitosan/β-cyclodextrin loaded theophylline as pulmonary sustained drug delivery carriers, the characteristics and ciliotoxicity were studied. The drug loadings of chitosan/β-cyclodextrin and carboxymethyl chitosan/β-cyclodextrin microspheres were 21.09% and 21.42%, and the encapsulation efficiencies were 91.40% and 92.80%. The distributions of 50% (d _0.5) of chitosan/β-cyclodextrin and carboxymethyl chitosan/β-cyclodextrin microspheres were 4.89 and 5.83 μm, respectively. Both microspheres showed spherical shape with smooth or wrinkled surfaces. FT-IR of chitosan/β-cyclodextrin microspheres demonstrated that theophylline had formed hydrogen bonds with chitosan and β-cyclodextrin, while for the carboxymethyl chitosan/β-cyclodextrin microspheres theophylline had interaction with carboxymethyl chitosan. The moisture absorption showed that an equilibrium was reached within 24 h. The two microspheres possessed better adaptability. In vitro release of theophylline from chitosan/β-cyclodextrin microspheres was slower than that from carboxymethyl chitosan/β-cyclodextrin microspheres at pH 6.8. Biography: LI Ruobao(1968–), male, Associate professor, research direction: foundation research of respiratory system.     

Surface interactions of MoO3/ α-Fe2O3 system

α-Fe₂O₃ -supported molybdena catalysts have been prepared by heating a mixture of MoO₃ and α-Fe₂O₃. XRD, XPS, LRS, TG-DTA and Mössbauer spectroscopy were used to characterize the interactions between MoO₃ and α-Fe₂O₃. The dispersion capacity of MoO₃ on the surface of α-Fe₂O₃ determined by XRD and XPS was 0.8 mmol/100m² α-Fe₂O₃ in the samples calcined at 420 . For the sample with low MoO₃ loading, LRS and FT-IR results showed that Mo⁶⁺ ions were located in the tetrahedral vacant sites on the surface of α-Fe₂O₃, signed as Mo- . The amount of Mo-II species, formed by Mo6+ ions incorporated into the octahedral vacant sites, increased with the MoO₃ loading. Based on the assumption that the (001) plane of α-Fe₂O₃ is preferentially exposed, almost all the Mo⁶⁺ ions of the dispersed molybdena species existed at the surface octahedral sites for the sample with MoO₃ loading close or beyond the dispersion capacity, and formed the Mo-II species. In this case, the capping O^2- ions linking with the incorporated Mo⁶⁺ ions formed a surface epitaxial structure, which was in good agreement with the results predicted by the incorporation model proposed previously. XRD and Mössbauer spectroscopy of the MoO₃ α-Fe₂O₃ samples calcined at different temperatures showed that the calcination temperature could strongly influence the interaction extent: ( i) at 420 , MoO₃ dispersed on the surface of α-Fe₂O₃ and formed surface Mo species; (ii ) at 500 , MoO₃ reacted with the bulk of α-Fe₂O₃ and formed Fe₂(MoO₄)₃ compound.