不同滑动条件下与氧化铝对摩时灰铸铁中石墨的减摩抗磨作用

考察了灰铸铁/A12O3陶瓷摩擦副在干摩擦、蒸馏水、乳化液和机油润条件下的摩擦磨损特性,并分析灰铸铁中石墨在不同润滑剂润滑下的减摩作用。结果表明：在这几种润滑条件下A12O3陶瓷和铸铁摩擦副的摩擦系数及摩损量都有所降低;在干摩擦及蒸馏水润滑下,石墨能起减摩耐磨作用;而在乳化液及油润滑下石墨难以起到润滑作用。     

氟离子配位在氧化法制备高铁(Ⅵ)酸盐中的作用

氟离子配位在氧化法制备高铁(Ⅵ)酸盐中的作用;高铁(Ⅵ)酸盐;六氟合铁(Ⅲ)酸钾;次氯酸钠;稳定性     

尖晶石型复合硫化物的合成和性能

尖晶石型化合物是一类具有丰富结构类型和应用潜力的功能材料,其在磁性材料、光电材料、电极材料、超导材料、催化材料等领域具有巨大的应用前景。对于硫系尖晶石型化合物AB2S4,由于S原子比O原子具有更大的原子半径,尖晶石型复合硫化物呈现出不同于复合氧化物的物理性质,近年来各国学者对其合成和物理性能进行了大量的探索和研究。本文总结了尖晶石型复合硫化物的合成方法及应用领域,并展望了其未来的发展方向。     

A conservative Fourier pseudospectral algorithm for the nonlinear Schrdinger equation

In this paper, we derive a new method for a nonlinear Schrodinger system by using the square of the first-order Fourier spectral differentiation matrix D1 instead of the traditional second-order Fourier spectral differentiation matrix D2 to approximate the second derivative. We prove that the proposed method preserves the charge and energy conservation laws exactly. A deduction argument is used to prove that the numerical solution is second-order convergent to the exact solutions in ｜｜·｜｜2 norm. Some numerical results are reported to illustrate the efficiency of the new scheme in preserving the charge and energy conservation laws.     

A novel hierarchy of differential integral equations and their generalized bi-Hamiltonian structures

With the aid of the zero-curvature equation, a novel integrable hierarchy of nonlinear evolution equations associated with a 3 x 3 matrix spectral problem is proposed. By using the trace identity, the bi-Hamiltonian structures of the hierarchy are established with two skew-symmetric operators. Based on two linear spectral problems, we obtain the infinite many conservation laws of the first member in the hierarchy.     

利用自由基反应合成（S）-（＋）-娃儿藤碱及其类似物

通过自由基反应,成功的合成了（S）-（＋）-娃儿藤碱（1）及其类似物．以2,3,6,7．四甲氧基菲甲酸为原料通过两或三步分别制得（-）-N-（2,3,6,7,四甲氧基-9-菲苄基）．2．溴甲基四氢吡咯（7）和（-）-N-（2,3,6,7-四甲氧基-9-菲甲酰基）-2-溴甲基四氢吡咯（9）．在催化量的偶氮二异丁腈参与下,溴化物（7）与三正丁基氢化锡反应没有得到预期的产物（S）-（＋）-娃儿藤碱,却以较高的收率得到N-（2,3,6,7-四甲氧基-9-菲苄基）哌啶（2）.通过分析机理,改用溴化物（9）为底物在同样的条件下分别以33．6％和65％的收率制得（S）-（＋）-9-娃儿藤酮（10）和（-）-N-（2,3,6,7-四甲氧基-9-菲甲酰基）-2-甲基四氢吡咯（11）．通过实验发现,化合物（10）和（11）的收率与偶氮二异丁腈的加入量密切相关．我们认为偶氮二异丁腈在该反应中充当着双重角色,并提出了可能机理．化合物（10）和（11）经四氢锂铝还原顺利得到（S）-（＋）-娃儿藤碱（1）和其结构类似物（＋）-N-（2,3,6,7-四甲氧基-9-菲苄基）-2-甲基四氢吡咯．     

1,2,4-噁二唑类化合物的合成及抗菌活性研究

以对溴苯腈为原料,通过多步反应合成了一系列3-(吗啉苯基)-5-取代-1,2,4-异噁唑类化合物和3-(吗啉苯基)-5-取代-4,5-二氢-1,2,4-噁二唑类化合物,并用1HNMR、13C NMR和MS进行了结构确证。这些化合物对测试的部分革兰氏阳性菌,如金黄色葡萄球菌、耐甲氧西林金黄色葡萄球菌、表皮葡萄球菌、粪肠球菌显示出一定的抗菌活性,但与噁唑烷酮类上市药物利奈唑胺相比,抗菌活性有明显下降。这一结果表明对于化合物的抗菌活性,1,2,4-噁二唑杂环不如噁唑烷酮结构有效。     

An extension of the modified Sawada—Kotera equation and conservation laws

Based on the modified Sawada-Kotera equation, we introduce a 3 × 3 matrix spectral problem with two potentials and derive a hierarchy of new nonlinear evolution equations. The second member in the hierarchy is a generalization of the modified Sawada-Kotera equation, by which a Lax pair of the modified Sawada-Kotera equation is obtained. With the help of the Miura transformation, explicit solutions of the Sawada-Kotera equation, the Kaup-Kupershmidt equation, and the modified Sawada-Kotera equation are given. Moreover, infinite sequences of conserved quantities of the first two nonlinear evolution equations in the hierarchy and the modified Sawada-Kotera equation are constructed with the aid of their Lax pairs.     

InAlO3（ZnO）15超晶格纳米串的合成及其电学性质

通过化学气相沉积方法成功合成了InAlO3(ZnO)15超晶格纳米串。扫描电镜观察到InAlO3(ZnO)15纳米片沿生长方向均匀排列,直径约为80～150 nm,长度约为7～20μm。X射线衍射结果表明样品具有InAlO3(ZnO)15超晶格纳米结构。高分辨透射电子显微镜显示相邻两个In-O层中间共16层In(Al)O(ZnO)m+block,并研究了其生长机制。在0.6～3 V电压范围内,I-V特性曲线出现非线性性质。