HL-1装置逃逸电流的数值模拟

本文对HL-1装置放电中的逃逸电流进行了零维数值模拟。考虑了逃逸电子的产生和损失,电子及离子的能量平衡与粒子数平衡。数值结果与实验较为符合。     

铥、镱、钇对铽-苯甲酰异羟肟酸配合物荧光的增强作用

本文通过对Tm（Ⅲ）-苯甲酰异羟肟酸（BHA）体系的发射光谱和激发光谱分析,研究了铥、镱和钇离子对Tb-BHA体系的发光性质的增强作用。测得了增敏离子的最佳浓度分别为1.8×10-4mol/L(Tm3+),1.5×10-4mol/L(Yb3+)和2.0×10-4mol/L(Y3+).并对RE-BHA（RE=Tm,Yb,Y和Tb）的固态配合     

The automatic interlocking system of electron absorbed dose monitoring and irradiation process control

The paper describes the real time computer control system used for monitoring and control parameters of the electron irradiation facility. The process control is achieved through the control system made up of a personal computer, three I/O boards and an ISA interface board. The improved bipartition transport theory has been applied to calculate the absorbed dose of low energy electron. The experimental results proved that the dose control precision of the system has been greatly raised, and the other performance indexes have been obviously improved. This interlocking system may be used for dose monitoring and process control in BB radiation processing.     

Two new linear furanocoumarin glycosides from Angelica dahurica

Two new linear furanocoumarin glycosides, tert-O-β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranosyl-oxypeucedanin hydrate (1) and sec-O-β-D-apiofuranosyl-(1→6)-O-β-D-glucopyranosyl-oxypeucedanin hydrate (2), were isolated from the fresh roots of Angelica dahurica. The structures of new compounds were elucidated on the basis of spectral analysis.     

Surface characteristics of a self-polymerized dopamine coating deposited on hydrophobic polymer films

This study aims to explore the fundamental surface characteristics of polydopamine (pDA)-coated hydrophobic polymer films. A poly(vinylidene fluoride) (PVDF) film was surface modified by dip coating in an aqueous solution of dopamine on the basis of its self-polymerization and strong adhesion feature. The self-polymerization and deposition rates of dopamine on film surfaces increased with increasing temperature as evaluated by both spectroscopic ellipsometry and scanning electronic microscopy (SEM). Changes in the surface morphologies of pDA-coated films as well as the size and shape of pDA particles in the solution were also investigated by SEM, atomic force microscopy (AFM), and transmission electron microscopy (TEM). The surface roughness and surface free energy of pDA-modified films were mainly affected by the reaction temperature and showed only a slight dependence on the reaction time and concentration of the dopamine solution. Additionally, three other typical hydrophobic polymer films of polytetrafluoroethylene (PTFE), poly(ethylene terephthalate) (PET), and polyimide (PI) were also modified by the same procedure. The lyophilicity (liquid affinity) and surface free energy of these polymer films were enhanced significantly after being coated with pDA, as were those of PVDF films. It is indicated that the deposition behavior of pDA is not strongly dependent on the nature of the substrates. This information provides us with not only a better understanding of biologically inspired surface chemistry for pDA coatings but also effective strategies for exploiting the properties of dopamine to create novel functional polymer materials.     

PSF-g-P(PEGMA)的合成及其共混超滤膜的制备与性能研究

以氯甲基化双酚A型聚砜(PSF-CH2Cl)为大分子引发剂,通过原子转移自由基聚合(ATRP)法合成了以聚砜(PSF)为疏水主链、聚(聚乙二醇单甲醚甲基丙烯酸酯)[P(PEGMA)]为亲水侧链的梳状两亲性共聚物PSF-g-P(PEGMA).FT-IR和1H-NMR的表征结果证实了两亲性共聚物的生成.将PSF-g-P(PEGMA)与PSF进行共混,通过浸没沉淀法制备了共混超滤膜.研究发现,引入5 wt%的PSF-g-P(PEGMA),共混膜的孔隙率和平均孔径分别从65.9%和0.08μm提高到81.9%和0.18μm;将共混膜于90℃热水中浸泡24 h后,膜表面O/S从14.63提高到17.16;共混膜的亲水性和抗牛血清蛋白(BSA)吸附性能显著提升.     

Determination of phenol in landfill leachate by using microchip capillary electrophoresis with end-channel amperometric detection

Phenol, 2,4-dichlorophenol (2,4-DCP), and 2,4,6-trichlorophenol (2,4,6-TCP) were baseline separated by using a homemade microchip CE with an end-channel amperometric detector where a 50 microm Pt microdisk working electrode (WE) and a Pt cathode were integrated onto the microchip itself. Separation parameters such as injection time and voltage, pH of the buffer, online pretreatment condition for WE, reproducibility, and detection potential were investigated. Under the selected separation conditions, the linear ranges for phenol, 2,4-DCP, and 2,4,6-TCP were 2-200, 4-400, and 4-400 microM, respectively. The LODs were 0.4, 0.5, and 0.7 microM for phenol, 2,4-DCP, and 2,4,6-TCP, respectively (S/N = 3). The standard addition method was successfully applied to the analysis of landfill leachate samples and the concentration of phenol in the landfill leachate samples was measured to be 0.32 and 0.21 mM, respectively. The recoveries were in the range of 85-103% and corresponding RSDs were less than 5.5%.     

Effect of the permeants/polymer interactions on the pervaporative separation properties of the P(VDF-co-HFP) membrane

In this paper, the acetone-cast poly(vinylidene fluoride-co-hexafluoropropylene) (P(VDF-co-HFP)) membranes were prepared by isothermally vacuum-dried at 60 °C and were employed in pervaporation of methyl acetate (MeAc) or ethyl acetate (EtAc) dissolved water solutions. DSC study on the swelling process indicated that two states of both MeAc and EtAc in their swollen P(VDF-co-HFP) membranes might exist which were the ‘bound state’ and ‘bulk state’. In addition, relative to the pure EtAc, the pure MeAc had stronger interaction with the P(VDF-co-HFP) membrane, making for its higher solubility in and lower diffusivity through the membrane. However, there is a competition between the organic permeants/water interactions and the organic permeants/polymer interactions when the P(VDF-co-HFP) membrane was tested for its pervaporative separating properties. With respect to MeAc in its water mixtures, EtAc in its water mixtures had higher solubility in the membrane instead because of its weaker interaction with water. As a result, better separating properties (higher permeate flux and separation factor) when the P(VDF-co-HFP) membrane was in pervaporation of the EtAc/water mixtures were obtained.     

Triterpene glycosides from <Emphasis Type="Italic">Lonicera</Emphasis>. II. Isolation and structural determination of glycosides from flower buds of <Emphasis Type="Italic">Lonicera macranthoides</Emphasis>

Two new triterpenoid saponins, lonimacranthoide II (8) and III (9), were isolated from the flower buds of Lonicera macranthoides Hand.-Mazz. (Caprifoliaceae), as well as one known saponin 10. The structures of the saponins were established based on chemical and spectral methods.