拟可微函数优化的Lagrange乘子与一阶最优性条件

本文给出了拟可微优化的Fritz John必须条件与Shapiro最优性必要条件的等价性质以及两个最优性充分条件.     

一类四阶变分不等式解的极限正则性

An example of a fourth order variational inequality is structed in this note. The example shows; u∈H^3+σ(Ω) with every σ<0.5(but u(?) H^3.5(Ω)) is limiting regularity of solution u of a fourth order variational inequality with displacement obstacle.     

Cascade synthesis of substituted 4-amino-1,2,4-triazol-3-ones from aldehyde hydrazones and azodicarboxylates

Substituted 4-amino-1,2,4-triazol-3-ones were synthesized from aldehyde hydrazones and azodicarboxylates in the presence of triphenylphosphine. The cascade reaction was conducted in a single step and the procedure is general and efficient.     

Nanoparticles consisting of optically active helical polymers: Preparation via aqueous catalytic miniemulsion polymerization and the effects of particles size on their optical activity

This article reports a class of nanoscale materials, that is, optically active nanoparticles consisting of helical‐substituted polyacetylenes. Such nanoparticles were prepared via aqueous catalytic miniemulsion polymerization, by which nanoparticles with a wide range of size (diameter: 60–400 nm) can be easily prepared. The nanoparticles could be obtained in quantitative monomer conversions. Large specific rotations and intense circular dichroism effects demonstrated that the nanoparticles possessed large optical activities; moreover, the optical activities were found to increase with a decrease in particle size. From the obtained polymer nanoparticles and with poly(vinyl alcohol) (PVA) as supporting material, composite films were further prepared and also exhibited considerable optical activities. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1661–1668, 2010     

Field emission characteristics of screen-printed carbon nanotubes cold cathode by hydrogen plasma treatment

Selective plasma etching and hydrogen plasma treatment were introduced in turn to improve field emission characteristics of screen-printed carbon nanotubes (CNTs) cold cathode, which was prepared by using slurry of mixture of multi-wall CNTs, organic vehicles and inorganic binder, i.e. silicon dioxide sol. The results show that selective plasma etching process could effectively remove parts of surface inorganic vehicle (SiO₂) layer and expose more smooth and clean CNTs on cathode surface, which could significantly decrease the operating field of CNTs cathode. There are some nanoparticles emerging on the out of CNTs wall after hydrogen plasma treatment, which are equivalent to increase field emission point of cathode. At the same time, these nanoparticles can increase the local electric field of CNTs, which can decrease operating voltage of CNTs cathode and improve uniformity field emission.     

Sm2O3对Ni／sepiolite甲烷化催化剂的影响

采用浸渍法制备了Ni/sepiolite及Ni-Sm/sepiolite催化剂并测定了催化剂的CO甲烷化活性，采用抗热实验，XPS及CS2中毒等手段研究了钐对Ni/sepiolite催化剂的影响，结果表明，加入Sm2O3提高了Ni/sepiolite催化剂的甲烷化活性，催化剂热稳定性及抗毒能力，降低了镍原子的电子结合能。     

Si doping effect on self-organized InAs/GaAs quantum dots

In situ ultra high vacuum scanning probe microscopy (SPM) and low-temperature photoluminescence (PL) studies have been performed on Si-doped self-organized InAs/GaAs quantum dots samples to investigate the Si doping effects. Remarkably, when Si is doped in the sample, according to the SPM images, more small dots are formed when compared with images from undoped samples. On the PL spectra, high-energy band tail which correspond to the small dots appear, with increasing doping concentration, the integral intensity of the high-energy band tail account for the whole peak increase too. We relate this phenomenon to a model that takes the Si atom as the nucleation center for QDs formation.     

Synthesis and properties of a novel polyester containing bithiazole

A novel Schiff base type polyester containing 2,2’-diamino-4,4’-bithiazole(DABT) was prepared by low-temperature interface polycondensation of 1,4-benzenedicarbonyl dichloride with 4,4’-(4,4’-bithiazole-2,2’-diylbis(imine-2,1-diyl)diphenol(BDDP), which is derived from a 2,2’-diamino-4,4’-bithiazole(DABT) Schiff base reacted with a 4-hydroxybenzaldehyde monomer.The newly generated polyester was evaluated based on characterization of its solubility,FTIR spectroscopy,elemental analysis,X-ray diffraction measurements and thermogravimetric analysis(TGA) studies.     

Efficient C-S cross coupling catalyzed by Cu2O

A protocol for the copper-catalyzed C-S bond formation between aryl, alkyl, or heteroaryl thiols and aryl or heteroaryl halides is reported. The reaction is catalyzed by Cu₂O which shows the highest catalytic activity with ethyl 2-oxocyclohexanecarboxylate ligand in DMSO at 80 °C. The corresponding coupling products are obtained with good to excellent yields under relatively mild reaction conditions with good chemoselectivity and functional group tolerance.