Wetting properties of polystyrene ionomers treated with plasma source ion implantation

The wetting properties of polystyrene‐based ionomers treated with plasma source ion implantation (PSII) were investigated by the measurement of water contact angles. When sulfonated ionomers were aged for a few days, the hydrophobic recovery for the ionomers became much slower than that for the nonionic polymers. However, when the samples were aged over 20 days, the water contact angle of the ionomers converged with that of the nonionic polymer. Thus, it was concluded that the ionic interaction between the ionic groups and the presence of ionic groups together resulted in the slow hydrophobic recovery and that the aging effect was significant for the ionomers. For the methacrylate ionomer of low ion content, on the other hand, it was found that the PSII treatment produced only a small change in hydrophobic recovery behavior. Thus, it was suggested that the low ionic content coupled with the small size of the ionic unit might cause changes only of a very insignificant degree in hydrophobic recovery behavior. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2500–2504, 2002     

Immobilization of biologically active species on PA‐6 foils treated by a dielectric barrier discharge

In the field of biomaterials and biomedical devices, surface activation has been focused on creating functional groups capable of preferential adsorption of biologically active species (proteins, enzymes, cells, drugs, etc.). In this way an interface can be created between the synthetic material and the biological medium, with the aim of increasing the compatibility of the implant with the human organism. In our experiments a dielectric barrier discharge (DBD), in helium at atmospheric pressure, was used as the source of energy capable of creating active centers that render the functionalized surface favorable to immobilization of biological molecules. Retention of immunoglobulin (IgG) and heparin biomolecules on polyamide‐6 (PA‐6) surfaces after treatment by the DBD was analyzed by atomic force microscopy, adhesion evaluation, and measurement of the contact angle titration in order to assess this incorporation on the treated surfaces. The marked adsorption of the biomolecules on the active sites created by DBD on the exposed surfaces also was related to a complex set of processes, such as enhanced roughness, increased surface wettability, and modified distribution of cationic and anionic groups on the treated surfaces. All these factors could promote interfacial interactions between the specific groups of the biomolecules existing in the biological medium and the type of cationic and/or anionic groups present on the surface. The efficiency of the DBD treatment showed that the DBD technique is useful for preactivation of the polymer surface for immobilization of other biologically active species (such as drugs and enzymes). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1985–1990, 2003     

蜡防印花生产废水处理工艺

对蜡防印花生产废水清污分流处理工艺进行了研究。结果表明：机械洗蜡废水分流后经双级气浮蜡回收处理，蜡回收率和处理水回用率可达90％以上；皂化脱蜡废水分流后采用酸化-加压溶气气浮技术处理，蜡回收率可达95％以上；皂化脱蜡处理水与印花废水经内电解预脱色处理，脱色率可达92％以上；各段处理废水与其它废水混合后经混凝气浮-生物接触氧化-沉淀-过滤组合工艺处理后，出水水质可达行业一级排放标准。该处理工艺处理效率高、费用低，经济效益和环境效益显著。     

Thermal crosslinking of collagen immobilized on poly(acrylic acid) grafted poly(ethylene terephthalate) films

Graft polymerization of acrylic acid onto plasma‐treated poly(ethylene terephthalate) (PET) films was used to prepare surfaces suitable for collagen immobilization by dip‐coating. Such surfaces could be used as matrices for smooth muscle cell cultures in tissue engineering. Contact angle measurements showed that plasma‐treated and grafted PET films undergo considerable surface reorganization during storage under ambient conditions. However, after collagen immobilization the contact angle remained relatively stable. The amount of collagen initially attached to the film surface increased with increasing poly(acrylic acid) graft density, but subsequent washing in water led to significant collagen loss. This loss could nevertheless be substantially reduced by thermal crosslinking of the collagen in the range 110–130 °C. Atomic force microscopy (AFM) observations suggested that the washed crosslinked collagen has a very similar structure to that of the un‐crosslinked collagen. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1874–1880, 2002     

Synthesis and Characterization of Hydrophobic TMES/TEOS Based Silica Aerogels

The experimental results on the effect of adding trimethylethoxysilane (TMES) as a co-precursor on the hydrophobicity and physical properties of tetraethoxysilane (TEOS) based silica aerogels, are reported. The molar ratio of TEOS, ethanol (EtOH), water (0.001 M oxalic acid catalyst) was kept constant at 1:5:7 respectively, while the molar ratio of TMES/TEOS (A) was varied from 0 to 0.6. It has been observed that as the A value increases, the gelation time increases. The hydrophobicity was tested by measuring the contact angle, and the surface chemical modification was confirmed by the FTIR spectroscopy studies. The thermal stability of the hydrophobic aerogels was studied in the temperature range from 25 to 800°C. The hydrophobic nature of the aerogel could be maintained up to a temperature of 287°C and above this temperature the aerogels become hydrophilic. The bulk density and the optical transmittance of the aerogels have been found to decrease with increase in A value. The aerogels have been characterized by Fourier transform infrared spectroscopy (FTIR), Optical transmittance, Scanning electron microscopy (SEM), Differential thermal analysis (DTA) and Thermogravimetric analysis (TGA), and Contact angle measurements.     

Host selection byBlepharipa pratensis (Meigen), a tachinid parasite of the gypsy moth,Lymantria dispar L.

The host selection process ofBlepharipa pratensis (Meigen), a tachinid parasite of the gypsy moth,Lymantria dispar L., was investigated. Once in the host's habitat, and following contact with a recently damaged leaf edge (cut, torn, eaten), the fly orients perpendicular to the edge and moves back and forth with the front tarsi grasping the damaged edge. Oviposturing (oviposition intention) may occur. Leaf exudates appear to arrest the fly on the leaf and increase tarsal examination (searching). If an edge of a gypsy moth-eaten leaf is contacted, oviposition usually occurs. Significantly more eggs are laid when host-browsed foliage is encountered, compared to mechanically cut or damaged foliage, indicating response to a cue left by the host during feeding. The number of host-damaged leaf clusters in an area significantly enhances oviposition there; in field-cage tests, significantly more eggs (7911) were laid in simulated-crown areas with all clusters browsed, compared to the adjacent areas containing 1/2 browsed (4200 eggs) and undamaged clusters (2209 eggs). A host selection sequence is suggested and discussed.     

UASB-接触氧化处理高浓度有机废水试验研究

本文主要通过UASB 接触氧化生化处理模型对某化工厂废水的试验研究，探索运用UASB法处理高浓度有机废水的可行性。同时还探讨了废水的CODcr及含盐量对UASB处理效率的影响，以及关键参数的选用。     

非接触CPU卡在环保排污上的应用

为确保环保排污重要数据交互、存储的安全性以及后台系统与前端总量计量设备数据传输的安全性,本文结合现有的排污许可证制度,提出了将国密SM1加密算法非接触CPU卡作为信息载体在环保排污上的应用模式,并对目前在浙江省环保领域应用的具体案例进行了剖析.     

Interaction of a shock pulse with a contact discontinuity

Passing of a triangular moderate-intensity pulse through a constant discontinuity is considered. Decay of the shock wave that passed into the second gas is analyzed. Damping of the detonation wave after burnout of the combustible mixture is discussed. __________ Translated from Fizika Goreniya i Vzryva, Vol. 43, No. 4, pp. 102–107, July–August, 2007.     

A glue method for fabricating membrane electrode assemblies for direct methanol fuel cells

We present a simple glue method for fabricating membrane electrode assemblies (MEA) for direct methanol fuel cells (DMFC). Rather than the conventional “dry” hot-pressing method that relies solely on hot-pressing at a high pressure and temperature to form a MEA, the “wet” method developed in this work introduces a binding agent, consisting of Nafion^® solution, between a polymer electrolyte membrane (PEM) and an anode/cathode. The introduced binding agent can provide a better adhesion and stronger binding force between a membrane and an electrode, thereby facilitating a better interfacial contact between the electrode and the Nafion^® membrane, which has been proved by scanning electron microscopy (SEM) analyses to the cross-sectional morphology of the MEA after long-term operation. The cell performance characterization showed the MEA fabricated by the glue method was more stable in cell performance than that fabricated by the conventional hot-pressing method. Cyclic voltammetry (CV) results also demonstrated the MEA fabricated by the glue method exhibited a higher electrochemical surface area (ESA) as a result of the improved interfacial contact between the Nafion^® membrane and the electrodes. Finally, the DMFC with the MEA fabricated by the glue method was characterized by the electrochemical impedance spectroscopy (EIS).