非齐次核的Hilbert型重积分不等式适配参数的等价条件及应用

利用权函数方法和实分析技巧，讨论了一类非齐次核■(λ₁λ₂>0)的Hilbert型重积分不等式的搭配参数，得到最佳搭配参数的充分必要条件及最佳常数因子的表达式。利用所得结果，讨论了相应的重积分算子的有界性及算子范数。     

化学文献印刷型检索工具及其进展

文献检索工具是报道、存贮和查找科技文献情报资料线索的工具,是为用户检索需要而组织编辑、整理出版的情报线索性出版物.我们主要依据它进行文献检索,进一步从有关文献中选取用于竞争活动的情报(intelligence).印刷型手工检索工具问世于今,已经300多年历史,至今仍与机械型检索工具并驾齐驱,共同承担报道、传播、交流科技文明的任务发挥作用.本文以印刷型检索工具为主,简介化学文献检索工具的发展、改进和现状.     

Two new secoiridoid glucosides from Syringa velutina Kom

Chemical investigation of Syringa velutina Kom. led to the isolation of two new secoiridoid glucosides. Their structures were identified as 6'-0-(6, 7-dihyrofoliamenthoyl)-8-epi-kingisidic acid (syrveoside A, 1) and 6'-O-menthiafoloyl-8-epi-kingisidic acid (syrveoside B, 2) on the basis of chemical and physicochemical evidence.     

助剂对负载型镍催化剂重整活性和抗积炭性能的影响

应用ＸＲＤ和催化活性评价手段，考察了助剂对Ｃ２重整制合成气的负勒型Ｎｉ催化剂的重整活性和其抗积炭性能的影响。实验结果表明，ＮｉＯ在γ－Ａｌ２Ｏ３表面上最大分散量随ＭｇＯ、Ｌａ２Ｏ３助剂的添加没程度地增大，助剂能影响负载型Ｎｉ催化剂 论性能，ＭｇＯ、Ｌａ２Ｏ３的添加对改善Ｎｉ催化剂的重整活性和抗积炭性能有明显效果，并与助剂的种类添加次序有关。     

有理插值型求积公式的存在性与收敛性

构造两种奇点预先给定的有理插值型求积公式(RIQFs),在一定条件下证明其存在唯一性和收敛性,结果推广了普通的插值型求积公式和Gauss型求积公式.     

RESERVOIR DESCRIPTION BY USING A PIECEWISE CONSTANT LEVEL SET METHOD

We consider the permeability estimation problem in two-phase porous media flow. We try to identify the permeability field by utilizing both the production data from wells as well as inverted seismic data. The permeability field is assumed to be piecewise constant, or can be approximated well by a piecewise constant function. A variant of the level set method, called Piecewise Constant Level Set Method is used to represent the interfaces between the regions with different permeability levels. The inverse problem is solved by minimizing a functional, and TV norm regularization is used to deal with the ill-posedness. We also use the operator-splitting technique to decompose the constraint term from the fidelity term. This gives us more flexibility to deal with the constraint and helps to stabilize the algorithm.     

泡沫镍及负载型镍催化剂制备纳米碳纤维层的研究

纳米碳纤维可用在催化材料、储氢材料、及纳米电子器件等方面。本文对用泡沫镍及负载型镍催化剂催化分解乙烯或丙烯制备纳米碳纤维进行了研究。利用X射线衍射仪、物理吸附仪、扫描电镜进行了分析表征,并考察了催化剂、碳源、生长温度对纳米碳纤维生长量、形貌、结构的影响。结果表明:在生长温度450℃,乙烯流率30mL/m in的条件下,负载型镍催化剂纳米碳纤维的生长量要高出泡沫镍3~6倍,负载型镍催化剂制备的纳米碳纤维直径为40~60纳米,小于泡沫镍的情况。泡沫镍催化分解乙烯制备纳米碳纤维时,纳米碳纤维的生长量和平均直径随温度的降低而逐渐减小。纳米碳纤维在泡沫镍上的最低生长温度为420℃,在低于480℃生长纳米碳纤维时泡沫镍的骨架结构不会被破坏,由此制备的纳米碳纤维在新型结构催化材料中有很好的的应用前景。     

含噻吩环的新推—拉型多环电光聚合物中间体的三阶非线性？…

以ＩＮＤＯ／ＳＣＩＯ方法的基础，利用完全态求和（ＳＯＳ）公式，计算了一系列新推－拉型多环电光聚合物间体的三阶非线性光学系数γ（－ω，ω，－ω，ω）、γ（０；０，０，０），研究了γ与分子骨架，给受取代基和噻吩环数目（共轭分子链长的关系）及其与外频率的关系，表明在链不十分长时，γ与链长的２．６９次方成正比。     

Generalized Dirichlet Normal Ordering in Open Bosonic Strings

Generally, open string boundary conditions play a nontrivial role in string theory. For example, in the presence of an antisymmetric tensor background field, they will lead the spacetime coordinates noncommutative. In this paper, we mainly discuss how to build up a generalized Dirichlet normal ordered product of open bosonic string embedding operators that satisfies both the equations of motion and the generalized Dirichlet boundary conditions at the quantum level in the presence of an antisymmetric background field, as the generalized Neumann case has already been discussed in the literature. Further, we also give a brief check of the consistency of the theory under the newly introduced normal ordering.