On sign-changing and multiple solutions of the p-Laplacian

In this paper, we construct the pseudo-gradient vector field in , by which we obtain the positive and negative cones of are both invariant sets of the descent flow of the corresponding functional. Then we use differential equations theory in Banach spaces and dynamics theory to study p-Laplacian boundary value problems with “jumping” nonlinearities at zero or infinity, and get new multiple solutions and sign-changing solutions theorems of p-Laplacian.     

Al-SBA-15介孔分子筛的合成、表征及其在苯酚叔丁基化反应中的催化性能

 通过嫁接的方法合成了Al-SBA-15介孔分子筛,用X射线衍射、透射电子显微镜、低温N2吸附和NH3程序升温脱附等方法进行了表征,并研究了其在苯酚叔丁基化反应中的催化性能. 结果表明, Al-SBA-15保持了母体SBA-15高度有序的六方介孔结构,具有较强的酸性,且在苯酚叔丁基化反应中表现出比Al-MCM-41更好的催化活性和2,4-二叔丁基苯酚选择性.     

热压交换单一稀土元素-Y型沸石的物理化学性能

系统的研究了经水热加压交换的La、Ce、Pr、Nd、Sm、Eu、Gd、Dy、Ho、Er、Tm、Yb与Y十三种LnY的一些主要物化性能,发现存在着一些规律与特点。1.水热加压交换度(a)与相对结晶度间成很好的对应关系,其中CeY具有高交换度与高结晶度的特点。2.LnY的晶胞常数,脱水温度,比表面随Ln原子序数的增大其变化趋向与Ln³⁺的ΔH水合变化趋向基本一致。3.LnY的晶格崩解温度随Ln³⁺离子碱度(φ=Z/r)的增大而提高。本文从结构的观点讨论了上述规律与特点的出现。     

沸石转晶的研究(Ⅲ)——NaY型沸石的稳定性及NaPc型沸石的结构

研究了原始凝胶3、3Na₂O·Al₂O₃·10SiO₂·200H₂O在100℃NaY型沸石向NaPc型沸石转晶的晶化过程,应用电子显微镜、X-射线衍射、TMS-GC和固体高分辨Si²⁹-NMR方法研究了沸石晶核的形成、晶体粒度和外貌的变化及液、固相中硅酸根离子存在状况及转晶中沸石结构的变化,并提出了转晶的液相传质机理。     

Polyvalent spherical aptamer engineered macrophages: X-ray-actuated phenotypic transformation for tumor immunotherapy

Spatiotemporally activatable immune cells are promising for tumor immunotherapy owing to their potential high specificity and low side effects. Herein, we developed an X-ray-induced phenotypic transformation (X-PT) strategy through macrophage engineering for safe and efficient tumor immunotherapy. Without complex genetic engineering, the cell membranes of M0-type macrophages were chemically engineered with AS1411 aptamer-based polyvalent spherical aptamer (PSA) via the combination of metabolic glycan labelling and bioorthogonal click reaction. Owing to the superior specificity, affinity and polyvalent binding effects of the high-density AS1411 aptamers, the engineered macrophages could easily recognize and adhere to tumor cells. With further X-ray irradiation, reactive oxygen species (ROS) generated by the Au-based PSA could efficiently transform the accumulated macrophages in situ from biocompatible M0 into antitumoral M1 phenotype via activating the nuclear factor κB signaling pathway, thereby achieving tumor-specific killing. In vitro and in vivo experiments confirmed the high tumor recognition and X-ray-induced polarization effect of the engineered macrophages. Compared to natural macrophages, our engineered macrophages significantly inhibited tumor growth in mice even if the radiation dose was reduced by three-fold. We believe this X-PT strategy will open a new avenue for clinical immune cell-based therapy.

An X-ray-induced phenotypic transformation strategy (X-PT) through macrophage engineering was developed for safe and effective immunotherapy.     

杯芳烃LB膜修饰电极及其识别性能

为了得到性能好的修饰电极,尝试使用不同的杯芳烃制作LB膜修饰电极,研究了不同空腔大小的和不同上缘取代基的杯芳烃LB膜成膜情况,发现对叔丁基杯芳烃和对烯丙基杯[4]芳烃都可以得到稳定的LB膜,杯环大小可以影响成膜的平均分子占有面积。不同取代基的杯芳烃识别金属铊离子的性能不同,叔丁基基本没有特别的响应,烯丙基有较好的响应,这应归因于电极表面烯丙基对铊离子的吸附或络合作用。     

正多边形弹性薄板的弯曲解

提出了一种在极坐标下求解正多边形薄板弯曲的新方法。在均布荷载条件下,通过选取满足特定对称条件的试函数,得到正多边形弹性薄板弯曲问题的级数展开解法,在挠度或弯矩表达式中仅取前5项,就可获得较高精度的结果,该方法能较好地解决特定正多边形薄板的弯曲问题,既可适用于求解均布荷载下的任意正多边界薄板的弯曲问题,也可以推广到承受任意荷载的任意正多边形薄板。     

Non-crystalline surface-modified hollow nanospheres of silica (HNS): Synthesis,characterization and catalytic application

Non-crystalline surface-modified hollow nanospheres of silica (HNS) with different amine groups were synthesized by the co-condensation under neutral conditions. The obtained materials were characterized by N₂ adsorption–desorption isotherms, Fourier-transform infrared spectroscopy (FTIR), transmission electron micrographs (TEM), scanning electron micrographs (SEM), back titration, elemental analysis and thermogravimetric analysis (TGA). The effect of organoamine type, amine density, and the presence of silanol groups on the catalytic activity was investigated. The capping of silanols with trimethylsilyl groups resulted in a reduction in catalytic activity, indicating the existence of cooperative effect between amine and silanol in the condensation reaction.     

波尔多液的施用对套袋苹果铜含量的影响

以不同地区、不同果园套袋栽培红富士苹果为试材,用火焰原子吸收法对施用波尔多液的套袋苹果中的铜含量进行了测试。结果表明,不同地区、不同果园的红富士苹果中的铜质量分数为0．45～1．07mg／kg,均低于我国卫生标准（GB15199-94）中水果中铜元素限量10mg／kg,其中套袋苹果中铜元素平均含量是不套袋苹果中铜元素平均含量的62．7％。每天食用适量苹果可以满足人体对铜元素的需求,且不易产生铜中毒等副作用。