Banach空间中非线性混合型微分积分方程的可解性

在序Ｂａｎａｃｈ空间中，研究了非线性混合型微分积分方程初值问题解的存在性，改进了文［１］中的相应结果．     

Preparation of Disulfides by the Oxidation of Thiols Using Bromine

Medium length aliphatic disulfides are easily synthesized via the bromine-oxidation ofthiols in the absence of solvent. Bromine can also oxidize long aliphatic and aromatic thiols to disulfides in solution. All yields are quantitative.     

Ce掺杂对碳纳米管负载Mn催化剂结构及SCR反应性能的影响

采用等体积浸渍法制备多壁碳纳米管(MWCNTs)负载Ce-Mn的催化剂,考察了Ce掺杂对Mn/MWCNTs催化剂上NH₃选择性催化还原(SCR)NO_x反应活性的影响.并运用透射电镜扫描、N₂吸附-脱附、程序升温还原、X射线光电子能谱、X射线衍射等手段,重点考察了Ce掺杂对Mn/MWCNTs催化剂结构性质的影响.结果表明,Ce掺杂能显著提高催化剂的SCR活性,其活性增量随着Ce含量的增加先增大后减小;当Ce/Mn为0.6时,催化剂活性最佳.表征结果显示,Mn/MWCNTs中添加Ce后,金属氧化物在MWCNTs上的分散程度提高;催化剂的比表面积和孔体积增大,平均孔径减小;氧化能力提高;表面氧含量增加,Mn化合价升高;结晶度降低,Mn主要以无定形或微晶形式存在,Ce主要以CeO₂物相存在.     

Synthesis of acenes via coupling of 1,4-dilithiobutadienes with diiodoarenes in the presence of CuCl

Dilithiobutadienes prepared from diiodobutadienes reacted with diiodobenzene or diiodonaphthalene to afford substituted naphthalene, anthracene, dihydronaphthacene, and dihydropentacene derivatives in the presence of CuCl and DMPU. Dihydronaphthacene and dihydropentacene derivatives were converted into the corresponding naphthacene and pentacene derivatives.     

非线性非单调二元算子方程组的解及其应用

利用非线性泛函分析中的锥理论和单调迭代的方法,研究了一类非线性非单调二元算子方程组的解的存在性,并给出了收敛于解的迭代序列,然后作为应用,得到了B anach空间中的一类非线性V olterra型积分方程组的解,改进了最近的许多结果.     

Nonionic emulsion-mediated synthesis and characterization of Zeolite Y

Zeolite Y was first synthesized in a nonionic emulsion system containing polyoxyethylated alkyl phenol surfactant and then characterized using XRD, SEM, FT-IR, TG-DSC, N₂ adsorption and carbon content analysis techniques. Compared to the conventional zeolite Y, the reported Y sample presents extraordinarily agglomerated and coalesced structure with huge BET surface area of 646.85 m²/g. The huge surface area is explained by the removal of emulsion components occluded in the pore structure of the Y sample through calcination. Parameters such as emulsion components, emulsion composition, cosurfactant identity and reaction conditions were investigated. It is found the emulsion induces rapid growth, as crystallization of zeolite Y is completed after 4 h, compared to 16 h for the sample that does not contain the emulsion components. Emulsion composition and cosurfactant identity greatly influence the morphologies and crystallinity of the Y samples. Control experiments indicate all the components of the emulsion system are necessary for the rapid growth of zeolite Y. Finally, zeolite growth mechanism in the nonionic emulsion system is tentatively proposed.     

Second-order nonlinear singular Sturm-Liouville problems with integral boundary conditions

This paper is concerned with the second-order singular Sturm-Liouville integral boundary value problems

     

The existence and nonexistence of entire positive solutions of semilinear elliptic systems with gradient term

We show the existence and nonexistence of entire positive solutions for semilinear elliptic system with gradient term Δu+|∇u|=p(|x|)f(u,v), Δv+|∇v|=q(|x|)g(u,v) on RN, N?3, provided that nonlinearities f and g are positive and continuous, the potentials p and q are continuous, c-positive and satisfy appropriate growth conditions at infinity. We find that entire large positive solutions fail to exist if f and g are sublinear and p and q have fast decay at infinity, while if f and g satisfy some growth conditions at infinity, and p, q are of slow decay or fast decay at infinity, then the system has infinitely many entire solutions, which are large or bounded.     

Disinfect Porphyromonas gingivalis Biofilm on Titanium Surface with Combined Application of Chlorhexidine and Antimicrobial Photodynamic Therapy

Various antimicrobial modalities have been proposed to treat peri‐implantitis but resulted in limited outcomes. The aim of this in vitro study was to evaluate the disinfection efficacy of combined application of chlorhexidine digluconate (CHX) and antimicrobial photodynamic therapy (aPDT) of titanium surfaces previously contaminated with Porphyromonas gingivalis biofilm. P. gingivalis biofilms were grown on 32 polished and 32 sandblasted large‐grit acid‐etched (SLA) titanium surfaces. Titanium disks were allocated into four groups as follows: (1) immersed in phosphate‐buffered saline (PBS), (2) immersed in 0.2% CHX, (3) application of aPDT and (4) immersed in 0.2% CHX and subsequent aPDT. Residual bacteria were determined by microbial culture analysis and by scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) imaging. Combination protocol (CHX+ aPDT) was the most effective in eradicating P. gingivalis (P < 0.05) on both polished and SLA surfaces. There was no significant difference in the number of remaining P. gingivalis between polished titanium disks and the SLA ones in four groups (P > 0.05). Under the limitation of this study, combined technique of preceding application of CHX and subsequent aPDT was shown to be an efficient method in reducing P. gingivalis numbers in both polished and SLA titanium surfaces.     

Banach空间非线性混合型微分－积分方程的解

本文利用一些新的比较结果研究了Ｂａｎａｃｈ空间中非线性混合型微分积分方程初值问题的最大解和最小解，唯一解以及解的迭代逼近，统一和推广了最近的许多结果。