铸方凝神韵——吴志平紫砂艺术

宜兴紫砂艺坛,自明代供春出现后,历代名手不断,名壶名作被皇室、宫廷收藏,身价倍增。特别是当今紫砂,在改革开放的大潮中,得到了飞跃的发展而成为海内外艺术品市场上的珍品。紫砂行业的队伍,大师们领头,许多优秀的中青年工艺师也在这繁华似锦的艺苑中展现个人的艺术才华和创新创作能力,使得原就方飞一式、圆不一相的紫砂壶艺变得更加丰富多彩。

EXPERIMENTAL RESEARCH AND NONLINEAR FINITE ELEMENT ANALYSIS ON NEW TYPE JOINT BETWEEN COLUMN AND STEEL BEAM OF CONCRETE-FILLED RECTANGULAR STEEL TUBULAR

Experimental results of new type joints between the column and the. steel beam of concrete-filled rectangular steel tubular （CFRT） under reversed cyclic loads are presented. The earthquake resistant capacity of the joint is influenced by infilled concrete, stiffener length and relative dimensions of column and beam. It is found that the hysteresis curves obtained in the experiment are full and the joints have a good energy dissipation capacity. The nonlinear finite element models are also used to analyze the hysteresis behavior of the joints under reversed cyclic loads using ANSYS 8.0. The influences of the stiffener length and the infilled concrete are analyzed. Analytical results show that the stiffener length and the infilled concrete are critical for the joints. Furthermore, the skeleton curves of the finite element models are in good agreement with those of experiments.

关于极坐标和直角坐标的互化的一点注记

全日制十年制学校高中数学二册课本P181推导出极坐标和直角坐标的互化公式,即 x=ρcosθ,y=ρsinθ.(1) ρ~2=x^2+y^2,tgθ=y/x,(x≠0) (2) 教材接着指出:在一般情况下,ρ取正值,由tgθ确定θ角时,应根据点M所在的象限取最小正角。利用公式(1)、(2),可以把点的坐标或曲线的方程由直角坐标的化成极坐标的,或由极坐标的化成直角坐标的。课本强调在一般情况下,ρ取正值,这在练习与习题中绝大多数题都是奏效的,正因为这一点,不少人,甚至有些书刊都忽视在某些问题中,ρ必须取正、负值,或者只能取负值。例如,由人民教育出版社出版的“全日制十年制学校高中数学第二册教学参考书P218对课本P189习题二十三第12题所作答案是极坐标方程为ρ=2αsinθcosθ,即ρ=αsin2θ(1),

Microstructure and crystal growth direction of Al-Cu alloy

The microstructures and crystal growth directions of permanent mould casting（PMC） and directionally solidified（DS） Al-Cu alloys with different contents of Cu were investigated. Simultaneously, the effects of pouring temperature on the microstructure and crystal growth direction of permanent mould casting pure Al were also discussed. The results indicate that the α（Al） crystals in the pure Al do not always keep common columnar grains, but change from the columnar grains to columnar dendrites with developed arms as the pouring temperature rises. The growth direction also varies with the change of pouring temperature. Cu element has similar effects on the microstructures of the PMC and DS casting Al-Cu alloys and the α（Al） crystals gradually change from columnar crystals in turn to columnar dendrites and developed equiaxed dendrites as the Cu content increases. The crystal growth direction in the PMC alloys gradually approaches （110） orientation with increasing Cu content. But the resulting crystals with growth direction of （110） do not belong to feathery grains. There are also no feathery grains to form in all of the DS Al-Cu alloys.

Microstructure control and mechanical properties of directionally solidified TiAl-Nb alloys

The double directional solidification（DS） technique was developed to control the lamellar microstructures in primary β TiAl-Nb alloys.Polysynthetically twinned（PST） crystals with lamellar boundaries parallel to or inclined 45o to the growth direction were achieved due to the complete peritectic transformation during directional solidification of the alloys with the dendritic solid/liquid interface.The PST crystals with aligned lamellar boundaries only parallel to the growth direction were produced when lamellar grains with lamellar boundaries in the same orientation were seeded by themselves under appropriate growth conditions.Low boron addition is harmful to align the lamellar orientation because of the growth of non-peritectic α phase.Due to the larger yttria particles and boride ribbons in the directionally solidified TiAl-Nb alloys,the tensile plastic elongations of the alloys are only close to 2%.

Application of ALE Method on the Numerical Simulation of Reinforced Concrete Penetration

LS-DYNA program and the principle of ALE method were introduced, and the target features of the reinforced concrete penetration were analyzed by using the D material model and the ALE method. A numerical simulation has been done to show the penetration visually and veritably. The simulation results are analyzed carefully and explicitly prove their significance to the research of reinforced concrete penetration.

复方蜥蜴散凝胶对溃疡性结肠炎模型大鼠Cingulin、Occludin、ZO-1蛋白的表达影响

目的研究复方蜥蜴散凝胶对溃疡性结肠炎(UC)大鼠结肠组织Cingulin、Occludin、ZO-1蛋白的表达影响,探究其治疗UC的机制及疗效。方法选取SD雄性大鼠120只,随机分为空白对照组和模型组。模型组以2,4,6-三硝基苯磺酸(TNBS)造模,造模成功后,随机分为复方蜥蜴散凝胶低、中、高剂量组,柳氮磺吡啶组,模型对照组。分别用复方蜥蜴散凝胶不同浓度、柳氮磺吡啶、氯化钠溶液,灌胃及中药喂养方式治疗14 d,观察大鼠一般情况;干预治疗后处死动物,取病变结肠组织,western blot法和免疫组化法(IHC)检测大鼠结肠组织中Cingulin、Occludin、ZO-1蛋白的表达,并对实验结果进行统计分析。结果模型组与空白组比较:大鼠体质量明显减轻、毛色晦暗无泽、食量减少、喜扎堆。病变结肠组织中Cingulin、Occludin、ZO-1表达明显降低。各治疗组与模型组比较:复方蜥蜴散凝胶高、中、低剂量组及柳氮磺吡啶组较模型组体质量上涨、饮水及食量增加、较活跃、毛色光泽。通过western blot法和免疫组化法对大鼠结肠组织Cingulin、Occludin、ZO-1的蛋白表达分析:模型对照组与空白对照组比较,大鼠结肠组织中Cingulin、Occludin、ZO-1蛋白表达水平均降低(P<0.05);柳氮磺吡啶组及复方蜥蜴散凝胶各治疗组与模型组比较,Cingulin、Occludin、ZO-1蛋白表达水平均明显升高(P<0.05)。尤其以复方蜥蜴散凝胶高剂量组显著明显(P<0.01),说明复方蜥蜴散凝胶高剂量组溃疡性结肠炎黏膜的修复作用最强。结论复方蜥蜴散凝胶可修复损伤结肠黏膜,治疗UC疗效可观。

Influence of Integral Instability of Kramers-Kronig Transformation on Photoabsorption Cross Sections

The photoabsorption cross sections of condensed atoms and molecules have proven to be dependent not only on the imaginary parts but also on the real parts of the polarizabilities due to the strong interatomie interactions in condensed environment. The real parts of the polarizabilities calculated usually by using the famous Kramers-Kronig transformation （KKT） from the photoabsorption cross sections of the isolated atoms are very sensitive to the accuracy of the implementation method of the infinite integral in the KKT. The influence of the integral instability of the KKT and the real part of the polarizability on the variation of the photoabsorption cross sections with the number density and the structure of the condensed matter has been studied in the present work for the first time. The conclusion is that the integration method with interpolation has given more reasonable results than the direct truncation method if some appropriate interpolation functions have been used. Some notes and conclusions have also been given for the applications of the alternative coupled expressions of photoabsorption cross sections.

A method to refine crude cottonseed oil using non-toxic polyamine-based cationic polymers

The traditional method to refine crude cottonseed oil is time-consuming and expensive.This study evaluates the effectiveness of coagulation–flocculation–sedimentation process using quaternary polyamine-based polymers in refining crude cottonseed oil.Flocculated by four commercial polyamine-based cationic polymers(SL2700,SL3000,SL4500 and SL5000)with varied molecular weight(MW)and charge density(CD)and followed by coagulation with sodium hydroxide,crude cottonseed oil can be effectively purified.Free fatty acids,gossypol,pigments and trace elements are all effectively and sufficiently removed by the four polymers in a MW-and CDdependent manner.Our results suggest that the use of polyamine-based cationic polymers may offer an effective and feasible alternative to the traditional method for crude cottonseed oil refining.

Synthesis and structural characterization of macroporous bioactive glass

Porous sol-gel glass of CaO-SiO2-P2O5 system with macropores larger than 100 μm was prepared by adding stearic acid as pore former when the sintering was carried out at 700 ℃ for 3h.The sol-gel porous glass shows an amorphous structure. The diameter of the pore created by pore former varies from 100 to 300 μm, and macroporous glass has a narrow and small pore size distribution in mesoporous scale. The porosity and pore size of macroporous bioactive glass can be controlled.

Fabrication of LaAlO3 film by sol-gel process with corresponding inorganic

Well-cubic perovskite lanthanum aluminate (LaAlO3) film on (110) silicon substrate was fabricated by sol-gel method with corresponding inorganic salts. Lanthanum acetate and aluminum acetate glacial acetic acid solutions were prepared via ligand exchange starting from lanthanum nitrate hexahydrate and aluminum nitrate hexahydrate after being refluxed. (CH3CO)2O removed nitrates and the crystallized H2O completely, acetylacetone (AcAc) was partially bidentated with metallic ion of the metallic acetates and formed La(OAc)3 (AcAc)x, which were hydrolyzed into La(AcAc)3 (OH)x by ?x ?x adding 10 ml 0.4% methyl cellulose (MCL) solution. The La(AcAc)3 (OH)x, polymerizing and combining with MCL, ?x formed the LaAlO3 sol precursor with heteropolymeric structure and formed film easily. The epitaxial LaAlO3 film on Si(110) substrate was crystallized after being annealed in thermal annealing furnace for 650?750 °C/30 min. The mor- phologies and microstructures were characterized. The refractive index of the LAO film was 1.942 to 2.007; the dielectric constant and the dissipation factors were estimated to be 23?26 and 2.1×10?4 ? 2.4×10?4 respectively.

Nanoparticle Transport and Coagulation in Bends of Circular Cross Section via a New Moment Method

Transport of nanoparticles and coagulation is simulated with the combination of CFD in a circular bend. The Taylor-expansion moment method(TEMOM)is employed to study dynamics of nanoparticles with Brownian motion,based on the flow field from numerical simulation.A fully developed flow pattern in the present simulation is compared with previous numerical results for validating the model and computational code.It is found that for the simulated particulate flow system,the particle mass concentration,number concentration,particle polydispersity, mean particle diameter and geometric standard deviation over cross-section increase with time.The distribution of particle mass concentration at different time is independent of the initial particle size.More particles are concen-trated at outer edge of the bend.Coagulation plays more important role at initial stage than that in the subsequent period.The increase of Reynolds number and initial particle size leads to the increase of particle number concentration.The particle polydispersity,mean particle diameter and geometric standard deviation increase with decreasing Reynolds number and initial particle size.

Effect of condensation latent heat release on the relative vorticity tendency in extratropical cyclones:a case study

Taking an extratropical cyclone that produced extreme precipitation as the research object,this paper calculates the contribution of condensation latent heat release(LHR)to relative vorticity tendency based on the complete-form vertical vorticity tendency equation.The results show that the heating rate of convectional condensation LHR can reach up to about 40 times that of stable condensation LHR.Both the stable and convectional heating centers are higher than 700 hPa,which would cause∂Q/∂z>0 and a positive vorticity source in the lower troposphere.The vertical gradient of stable condensation LHR contributes little to the growth of relative vorticity,while the relative vorticity tendency associated with the vertical gradient of convectional condensation LHR can be an order of magnitude higher than the former.The positive vorticity source is always located right below the latent heating center,and its maximum value can always be found in the lower troposphere.Convectional LHR is the primary factor for cyclone development from the perspective of diabatic heating.The horizontal gradient of total condensation LHR can contribute about 65%of the actual vorticity growth,but the effect of the vertical gradient of convectional condensation(LHR)can reach twice as much.The adiabatic heating from LHR can cause vorticity tendency directly.However,it can also change the vertical and horizontal gradient of potential temperature,which can further induce vorticity tendency.

Analytic Study of a Bose-Einstein Condensate in Waveguide with an Obstacle Potential

We investigate the exact solutions of one-dimensional (1D) time-independent Gross-Pitaevskii equation(GPE),which governs a Bose-Einstein condensate (BEC) in the magnetic waveguide with a square-Sech potential.Boththe bound state and transmission state are found and the corresponding spatial configurations and transport propertiesof BEC are analyzed.It is shown that the well-known absolute transmission of the linear system can occur in theconsidered nonlinear system.

Combined therapy with transcatheter arterial chemoembolization and percutaneous microwave coagulation for small hepatocellular carcinoma

AIM:To assess the efficacy of combined transcatheter arterial chemoembolization(TACE)and percutaneous microwave coagulation therapy(PMCT)for small hepatocellular carcinoma(HCC). METHODS:Thirty-five patients with a total of 41 HCC nodules(≤3 cm in diameter)were treated with TACE followed by computed tomograghy(CT)-guided percutaneous microwave coagulation therapy(PMCT) within 1-3 wk. RESULTS:By biopsies and enhanced CT scans, complete necrosis of the tumor and 3-5 mm of the surrounding non-cancerous area were observed in 34 foci.In seven foci,incomplete necrosis of the surrounding parenchyma was observed.Serum alpha- fetoprotein(AFP)levels returned to normal 10 d after treatment in 25 patients who originally had high serum AFP levels.The follow-up period was 6-31 mo,and all patients remained alive.One patient had a recurrence in the subsegments of the liver,and another patient had a recurrence near the original lesion. CONCLUSION:Combined therapy with TACE and PMCT is a safe and effective treatment without severe complications for small HCC.

Reference in cohesion： From the perspective of text analysis

This paper attempts to explore how cohesion is realized by meanings of reference in text analysis. Through analyzing some aspects of reference, especially personal reference and demonstrative reference, we know that reference is a text characteristic beyond sentences. It contributes to the development of a text and makes the text more cohesive, communicative and accurate. Of course, reference in cohesion is not used separately, it is closely related with other aspects of text analysis, and they cooperate and restrain each other and perform functions together. So translators are required to have the competence of understanding and applying reference, ellipsis and other cohesive device from the viewpoint of texts level with the combination of other aspects in text analysis, then texts can be more cohesive, coherent and acceptable.

The construction design and practice of Three Gorges Project

The construction of Three Gorges Project (TGP) is characterized by large construction scale,high construction intensity and complexity in technology.In view of various technical difficulties such as navigation in construction period,two river closures,high-intensity concrete and earth-rock construction,high-intensity construction and demolition of RCC (roller compacted concrete) cofferdam in stage III and immediate navigation of double-line five-step shiplock after impoundment of reservoir,the scheme of river diversion during construction is adopted,namely "diversion in 3 stages,open channel navigation and cofferdam power generation".The practice and innovation achievements in river diversion during construction as well as earth-rock and concrete construction are presented emphatically.

Formation of twinned dendrites during unidirectional solidification of Al-32%Zn alloy

The present study focused on the formation and crystallographic orientation of twinned dendrites coexisting with equiaxed grains in unidirectional solidification of Al-32%Zn(mass fraction)alloy.The morphology was investigated by optical metallograph and electron back-scattered diffraction technique.Results showed that the macrostructure of the alloy exhibited a typical feathery and fan-like structure while the microstructures were elongated lamellas,which were separated by coherent and incoherent twin boundaries.Both the primary trunk and all lateral arms of twinned dendrites grew along〈110〉directions,unlike regular〈100〉α(Al)dendrites.The facet growth of crystals at solid/liquid interface was responsible for the origin of twinned dendrites during the weak local convection,and high thermal gradient and medium solidification velocity had significant contribution to the formation of twinned dendrites.The formation mechanism of twinned dendrites which consisted of three multiplication ways of new twin boundaries formation and one way of dendrite evolution in twin plane was shown schematically.