弧形混凝土结构温度应力计算研究     

黎永索  卫军 《湖南城市学院学报》2003,24(6):10-13

对弧形混凝土结构温度应力的计算研究表明，弧形结构的环向应力沿高度方向基本一致，可以简化为拱单元计算，拱单元的支座约束可以用“等效暗柱”来计算；结构两侧温差对弧形结构的环向应力的影响较轴线温差变化的影响更大，控制温度裂缝主要是控制结构物两侧的温差．通过设置滑动层，减小结构的抗侧移刚度。则弧形混凝土结构可以作无缝设计．  相似文献   

语言艺术在体育教学中的运用     

张弘强 《泰州职业技术学院学报》2011,11(2):47-48,51

在科技高速发展的今天,学校运用高科技手段进行教学,已成必然。作为一名教育工作者,特别是一线体育教师,一定的语言表达艺术水平,是必备的基本功。语言艺术的运用,直接影响到教育教学质量。文章就体育教师的语言能力运用,提出一些想法和做法。供大家在今后的教学中参考和借鉴。同时还须提醒各位教师语言艺术能力不但缺不得,更需要大力加强训练并不断提高。  相似文献   

Loop细分曲面的数控粗加工刀具路径生成方法   总被引：1，自引：0，他引：1  

梁伟文 《深圳职业技术学院学报》2007,6(3):3-6

以Loop细分曲面为例,介绍了细分曲面的三轴数控刀具路径生成方法。首先根据细分曲面的网格迭代特性,提出了一种Z-map模型技术和一种包络细分曲面的覆盖曲面方法,然后根据极限曲面与覆盖曲面的关系,调整网格顶点生成最终覆盖曲面,讨论了细分曲面的粗加工刀具路径生成方法。同时,为了解决加工干涉问题,提出了一种加工干涉检查和纠正方法。  相似文献   

奇奇核168Lu三轴超形变带的研究     

图雅  拉布敦  于少英 《湖州师范学院学报》2005,27(1):32-35

采用TRS方法对^168Lu新发现的一条三轴超形变转动带进行了理论计算，在理论上进一步证实了其存在的三轴超形变，并通过三维自洽计算得到了其形变参数值，结果与文献一致．  相似文献   

Microwave-assisted synthesis, anticonvulsant activity and quantum mechanical modelling of N-（4-bromo-3-methylphenyl） semicarbazones     

Shalini M  Yogeeswari P  Sriram D  Induja S 《Journal of Zhejiang University. Science. B》2007,8(1):45-55

Objective： To study the effect of halo substitution on disubstituted aryl semicarbazones on the anticonvulsant potential and model the activity based on quantum mechanics. Methods： A series of twenty-six compounds of N^4-（4-bromo-3-methylphenyl） semicarbazones were synthesized and evaluated for the anticonvulsant activity in the maximal electroshock seizure （MES） and subcutaneous pentylenetetrazole （scPTZ） seizure threshold tests. Some potential compounds were also tested in the subcutaneous strychnine （scSTY） and subcutaneous picrotoxin （scPIC） seizure threshold tests. The synthesized compounds were tested for behavioral impairment and CNS （central nervous system） depression in mice. Quantum mechanical modelling was carried out on these compounds to gain understanding on the structural features essential for activity. Results： Some compounds possessed broad spectrum anticonvulsant activity as indicated by their effect in pentylenetetrazole, strychnine, picrotoxin and maximal electroshock seizures models in resemblance to other aryl semicarbazone derivatives reported earlier. The higher the difference in HOMO （highest occupied molecular orbital） and LUMO （lowest unoccupied molecular orbital） energy levels was, the greater was the activity profile. Conclusion： The pharmacophoric requirements for compounds to exhibit anticonvulsant activity that includes one aryl unit in proximity to a hydrogen donor-acceptor domain and an electron donor have been justified with the molecular orbital surface analysis of the synthesized compounds.  相似文献   

Impact absorption of tennis shoe-surface combinations     

S.?J.?DixonEmail author  V.?H.?Stiles 《Sports Engineering》2003,6(1):1-9

The aim of this study was to investigate, for typical shoes and surfaces used in tennis, the relative role of the shoe and surface in providing cushioning during running. Five test surfaces ranging from concrete to artificial turf were selected, together with two shoe models. Impact absorbing ability was assessed mechanically using drop test procedures and biomechanically using peak magnitude and rate of loading of impact force and peak in-shoe pressure data at the lateral heel. Differences in biomechanical variables between shoe-surface combinations were identified using a two-way ANOVA (p < 0.05). Mechanical test results were found to rank the surfaces in the same order regardless of the shoe model, suggesting that the surface is influential in providing cushioning. However, for all mechanical and biomechanical (p < 0.05) variables representing impact absorbing ability, it was found that the difference between shoes was markedly greater than the differences between surfaces. The peak heel pressure data were found to rank the surfaces in the same order as the mechanical tests, while impact force data were not as sensitive to the changes in surface. Correlations between mechanical and biomechanical impact absorption highlighted the importance of testing the shoe-surface combination in mechanical tests, rather than the surface alone. In conclusion, mechanical testing of the shoe-surface combination was found to provide a strong predictor of the impact absorbing ability during running if pressure data were used. In addition, for typical shoe-surface combinations in tennis, the shoe was found to have more potential than the surface to influence impact loading during running. Finally, in-shoe pressure data were found to be more sensitive than force plate data to changes in material cushioning.  相似文献   

Nanocontainer aqueous systems for removing polymeric materials from marble surfaces: A new and promising tool in cultural heritage conservation     

Scilla Grassi  Monica Favaro  Patrizia Tomasin  Luigi Dei   《Journal of Cultural Heritage》2009,10(3):347-355

The present study dealt with the characterisation of marble surfaces coated by three kinds of polymeric material usually employed in stones conservation and with the evaluation of the removal of these coatings from the surfaces by means of new nanocontainer aqueous systems constituted of micellar solutions (MS) and oil-in-water microemulsions (MC). The polymeric coatings were also subjected to accelerated artificial ageing in order to detect possible effects associated to natural photochemical ageing. The aim of the work was the assessment of the performance of such nanocontainer aqueous systems taking acetone (Ac) as a reference “traditional” solvent for the removal procedure. The characterisation was carried out by means of Scanning Electron Microscopy (SEM) and Environmental Scanning Electron Microscopy (ESEM), Fourier Transform Infra-Red (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopies and the results obtained showed that the performance of these innovative methods based on nanocontainer aqueous systems can be considered highly promising in the view of a “green approach” to the conservation of cultural heritage.  相似文献   

用向量函数求解曲线积分和曲面积分     

王晓  汪小黎 《莆田学院学报》2014,(5)

为了方便计算曲线积分和曲面积分,利用向量函数表示空间曲线和空间曲面,给出计算第一类曲线积分和第一类曲面积分的两个定理,并给予详细证明;最后,通过实例分析,说明其应用方法。  相似文献   

鱼腹式连续弯箱梁桥承载能力评估研究     

梁俏 《福建工程学院学报》2014,(6)

以某鱼腹式连续弯箱梁为工程背景,针对其受力特点,结合成桥后静载试验和环境脉动试验,将试验结果与有限元理论值相比较,综合评估其承载能力,并得出鱼腹式连续弯箱梁桥实际荷载作用下的部分受力特性。为类似桥型的受力分析及承载能力评估提供一定的工程经验。  相似文献   

H3(-1)中具有一个常主曲率的曲面     

闻家君  陈抚良  胡名成 《江西教育学院学报》2006,27(3):3-5

文章讨论H 3(-1)了中具有一个常主曲率的曲面,得到了另一主曲率与该常主曲率之间的关系。  相似文献