基于Chebyshev-Ritz法分析多裂纹梁自振特性

基于弹性力学平面应力理论,利用Chebyshev-Ritz法分析多裂纹梁的自振特性. 根据裂纹情况将裂纹梁分成若干个梁段,用边界函数与第一类Chebyshev多项式的乘积构造各梁段的位移函数,具有很好的收敛性,能够适用于不同的几何边界条件. 用Ritz法得到各梁段的振动方程,根据各梁段之间的位移连续条件整合方程,建立整个裂纹梁的振动特征方程. 计算结果与有限元分析和相关文献数据吻合很好. 分析裂纹深度和位置对自振特性的影响. 随着裂纹深度的增大,裂纹梁的频率减小,振型的幅值变大,且影响的程度会受裂纹的位置影响.     

Nitrosation and Nitration of Tetraacetyldibenzylhexaazaisowurtzitane

Tetraacetyldibenzylhitane (TADBIW) was subjected to debenzylation by nitrosating with inorganic materials available commercially to synthesize tetraacetyldinitrosohexaazaisowurtzitane (TADNSIW). TADNSIW was purified, and its structure was determined by FTIR, 1H NMR, MS and element analysis. The debenzylation reaction of TADBIW gave quantitative benzaldehyde as a by-product. This indicates that the reaction produces an imine cation as an intermediate. Hexanitrohexaazaisowurtzitane (HNIW) was prepared from unpurified TADNSIW with the yield over 96.0 % and the purity more than 98.0 %. And the mechanism of the reaction from TADNSIW to HNIW is proposed to be oxidation of nitroso and nitration of acetyl on the molecule of TADNSIW, This reaction system involved is simple, and the reaction can complete within a short time and under mild conditions. The product can be easily to separate and the waste disposed readily.     

微生物絮凝剂产生菌的筛选及对镇江古运河水的应用研究

从土壤、活性污泥等试样中筛选得到5株具有絮凝活性的菌种,其中从沉淀池活性污泥中筛选出的菌株B2絮凝活性最高。并研究了pH值、碳源量以及氮源量的变化对该菌株絮凝活性的影响。结果表明：菌株B2的最佳培养条件是pH值为7．0、葡萄糖浓度为30．0g／L、酵母膏浓度为0．25g／L。同时该菌株对镇江古运河水的絮凝活性由68．4％提高到81．6％。     

砂质粉土水泥土无侧限抗压强度试验

通过对36组水泥土室内配方试验的归纳与分析,进行了室内4种因素影响下水泥土的无侧限抗压强度试验,定量分析了水泥掺量、养护龄期、水泥品种和养护方式对水泥土无侧限抗压强度的影响,揭示了各种因素对水泥土无侧限抗压强度的影响规律。试验结果表明:水泥土无侧限抗压强度随着龄期的增长而提高;水泥掺量、水泥品种和养护龄期是影响水泥土无侧限抗压强度的主要因素;对于水泥掺量小于10%的水泥土,养护方式对水泥土强度影响较大。试验结果还表明:无侧限抗压强度试验中的应力应变关系随水泥掺量的变化以及龄期都有较明显的变化趋势,水泥土试样随龄期的增长和水泥掺量的增加均变得越硬越脆,龄期越长、水泥掺量越大,应力应变关系曲线在上升段越陡峭。最后,从扫描电镜(SEM)试验照片中可以直观的看出水泥土随着水泥掺量的增加强度的变化规律。     

应用铟源的反应蒸发制备In2O3透明导电膜

本工作说明，在低压氧气氛中。应用铟源的反应蒸发很容易淀积高质量的Ｉｎ２Ｏ３透明导电膜．旦然没有使用锡杂质，但所得膜的性能可以和最好的掺锡的Ｉｎ２Ｏ３膜相比．膜电阻率达２～３×１０￣４Ω·ｃｍ，可见光透过率超过９０％，并且膜生长速率高达２１９／ｍｉｎ．文章对成膜过程作了分析，报道了膜的最佳淀积条件，对由于偏离最佳淀积参数而导致的异常膜的形成机制也进行了讨论．     

Imaging and nano-dissection of tobacco mosaic virus by atomic force microscopy

Tobacco mosaic virus (TMV) has been deposited on freshly cleaved mica substrates. The topography was investigated by contact, non-contact and lateral-force microscopy under ambient conditions in air. The results were in accord with known dimensions of TMV (i.e. 18 nm in diameter and 300 nm in length). However, convolution of tip shape with TMV morphology resulted in an apparent width of 80–140 nm in the lateral plane, a factor of 4–7 greater than the known diameter. Other artefacts - broadening and double images - were observed and ascribed to tip anomalies. High force loadings and slow repetitive scanning resulted in controlled removal of parts of the TMV structure. Accordingly, it was possible to reveal and image the central core channel of the TMV. The precision and resolution of dissection induced by AFM is currently limited by the shape of the tip, having a 40-nm radius of curvature for standard Si₃N₄ tips. It is estimated that sharper tips, with a radius of curvature of less than 10 nm, should be able to resolve, non-destructively, the protein subunits in the non-contact mode, and selectively remove single subunits in the contact mode.     

Investigating the acceptability of behavioral interventions in applied conjoint behavioral consultation: Moving from analog conditions to naturalistic settings.

Whereas there exists a vast literature investigating consumer satisfaction ratings of various behavioral interventions, the majority of these studies have been limited to analogue conditions, which may compromise utility and generalization. Additionally, most research has failed to explore multiple-source, multiple-setting data in the investigation of treatment acceptability. This study investigated parent, teacher, and child treatment acceptability ratings derived from field-based conjoint behavioral consultation cases. Data indicate that overall, 67 parents (aged 23-54 yrs), 67 teachers (aged 22-57 yrs), and 67 children (aged 5-15 yrs) rated conjoint behavioral consultation-based behavioral interventions as very to highly acceptable. For parents, interventions with a reductive component were rated as more acceptable than interventions using both positive and negative components; no significant differences were found among teacher and child group ratings. For teachers, there was a positive relationship between (a) intervention complexity and treatment acceptability ratings and (b) problem severity ratings and treatment acceptability ratings... (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

牛蒡复合益生菌酸奶发酵条件的优化

本研究以胡萝卜、牛蒡、山药等为原料,添加复合益生菌制备益生菌复合酸奶并对其发酵条件进行了优化。实验结果表明,胡萝卜、牛蒡、山药的添加质量分数分别为20%、15%和10%时,发酵温度在40℃时,时间在7 h条件下,发酵的复合益生菌酸奶品质最好。乳酸菌接种量为5%～6%时,复合益生菌酸奶的酸性约为80%,持水性约为70%;通过发酵温度和发酵时间的对比,证明复合益生菌酸奶最佳发酵条件为:接种量为5%,发酵时间为7 h,发酵温度为40℃。实验结果表明:所提发酵条件能够更好实现复合益生菌酸奶的发酵优化,且得到的酸奶发酵后质量最佳。     

黑菊芋中5-羟甲基糠醛制备及含量分析

高效液相色谱法(HPLC)测定5-羟甲基糠醛的含量。正交试验L9(34)确定黑菊芋中5-HMF的最佳制备方法,同时对不同保存时间黑菊芋(0,3,6和18 m)、黑蒜、乌酸酶,黑咖啡等几种食品中5-HMF含量进行分析。结果表明,最佳条件为温度40℃、料液比1︰8(g/mL),提取时间5 h;黑菊芋5-HMF含量随保存时间降低,且显著低于咖啡。研究为黑菊芋食品安全性评价提供实验依据。     

桑果醋发酵工艺研究

以桑果、糯米为原料，采用液态发酵法，酿制风味独特、营养丰富的桑果醋。通过对桑果汁压榨、浸提、澄清和酒精发酵、醋酸发酵等工艺的研究，确定桑果汁酶解澄清的最佳方案是：果胶酶添加量为0．035％、淀粉酶0．014%、明胶0．018％、硅溶胶0．018％；确定主要工艺参数为：酒精发酵阶段桑果清汁：糯米糖化醪=2：1，接种量5％，25℃发酵72h，酒精浓度6．0％，醋酸发酵阶段温度为33℃-35℃，接种量6．0％，起始pH6．0，500mL三角瓶装液量100mL，在转速140r／min条件下振荡培养72h左右，得到的成品醋酸度适宜，口感、风味良好。