应用改良BP网络于多组分药物定量分析

ＢＰ网络自身学习速度慢的缺点，影响了其在多组分同时定量分析中的应用，为此，本文从误差函数、传递函数和网络参数等方面应用Ｆａｈｌｌｍａｎ和Ｃａｔｅｒ等所提修改方案改了Ｂ Ｐ网络，并将其应用于甲硝唑、先锋霉素、氯纱和氨卞四组分混合药物的同时定量分析，实验证明，在不损害网络预测精度的前提下，学习速度有了较大的提高。     

STUDY ON THE EPOXY RESIN TOUGHENED BY HYDROXY-TERMINATED BUTADIENE-ACRYLONITRILE COPOLYMER

Toughened epoxy resin with excellent properties was obtained by adding organic acid anhydride curing agent and hydroxy-terminated butadiene-acrylonitrile copolymer (HTBN), which is cheaper than CTBN. The anhydride reacts with both epoxy groups on epoxy resin and hydroxyl groups on HTBN. As a result the soft long chains of HTBN and the rigid chain of epoxy resin form one network, giving the resin toughness. Two-phase structure of the toughened resin was observed by SEM and TEM.     

硅铁中硅、铝、磷的联合测定

采用一次称样、熔样,盐酸酸化后蒸至湿盐状,聚乙二醇聚合后过滤,形成残渣和滤下液。残渣用于以比色法测定硅含量,滤下液则用来分别测定铝(分光光度法)和磷(比色法)。该样品处理方式简化了分析步骤,降低了分析成本,硅、铝、磷的加标回收率在98.9%~103%之间,测定结果的相对标准偏差为0.18%~4.52%(n=6),标准样品的测定值与证书值一致。该方法可满足日常分析要求,特别适用于中小型实验室对硅铁样品质量的监控。     

Spherical symmetric solutions for the motion of relativistic membranes and null membranes in the reissner-nordström space-time

In this article, we concern the motion of relativistic membranes and null membranes in the Reissner-Nordström space-time. The equation of relativistic membranes moving in the Reissner-Nordström space-time is derived and some properties are discussed. Spherical symmetric solutions for the motion are illustrated and some interesting physical phenomena are discovered. The equations of the null membranes are derived and the exact solutions are also given. Spherical symmetric solutions for null membranes are just the two horizons of Reissner-Nordström space-time.     

Small-molecule fluorescent probes for the detection of carbon dioxide

This review summarizes the design principles, recognition mechanisms, properties and functions of various kinds of small-molecule fluorescent probes for the detection of carbon dioxide     

Interaction of the antimicrobial peptide dicynthaurin with membrane phospholipids at the air-liquid interface

This paper reports the first study on the interaction of the antimicrobial peptide dicynthaurin with 1,2-dipalmitoyl-glycerophosphatidyl-glycerol investigated in monolayers at the air-liquid interface. The influence of the peptide on the two-dimensional phase behavior of the negatively charged lipid was elucidated by means of pressure-area isotherm measurements, fluorescence microscopy, and grazing incidence X-ray diffraction measurements. The pure peptide forms a stable monolayer at the air-liquid interface up to 30 mN/m as shown for both the monomeric and the dimeric cynthaurins. The peptide lipid interaction was monitored in isotherm measurements showing a strong adsorption of the peptide and stabilization at the interface promoted by the lipid monolayer. The X-ray diffraction measurements in agreement with fluorescence microscopy studies showed that the peptide destabilizes the condensed chain lattice, leading to a complete fluidization of the condensed lipid phase on physiological buffer. The adsorption of the peptide to the negatively charged lipid monolayer and the fluidization of the condensed chain lattice suggest a direct link to the peptides' ability to expand the bacterial membrane that would be relevant for the in vivo mode of action.     

Preparation of styrene polymer/ZnO nanocomposite latex via miniemulsion polymerization and its antibacterial property

Styrene polymer/ZnO nanocomposite latex was fabricated using miniemulsion polymerization in the presence of coupling agent 3-aminopropyltriethoxysilane (APTES) and hexadecane as hydrophobe. The size distribution and morphology of the composite latex particles were characterized by dynamic light scattering and transmission electron micrograph. X-ray photoelectron spectroscopy and Fourier transform infrared spectrophotometer results demonstrate that ZnO nanoparticles were encapsulated into polymer phases. The coupling treatment of ZnO with APTES can improve the dynamic contact angles of ZnO nanoparticle with water to enhance its hydrophobicity. When 0.6% APTES to ZnO (wt/wt) is used to modify ZnO, the encapsulation efficiency of ZnO reaches to 95%. It shows that the high encapsulation efficiency improves dispersion of ZnO nanoparticles in polymer film by scanning electron microscope. The stable structural hybrid latex can adequately exert unique function of nanoparticles in coatings. It indicates that the coatings added the composite latex exhibits perfect antibacterial activity, which has a tremendous potentiality in the field of coating materials.     

Highly Efficient Visible‐Light Plasmonic Photocatalyst Ag@AgBr

Visible improvements : Owing to the plasmon resonance of silver nanoparticles deposited on the surface of AgBr, the newly‐prepared plasmonic photocatalyst Ag§AgBr has a strong absorption in the visible region (see picture) and shows high efficiency in the photodegradation of organic pollutants under visible light.

     

Three kinds of TVS in a SIR epidemic model with saturated infectious force and vertical transmission

Three different vaccination and treatment strategies in the SIR epidemic model with saturated infectious force and vertical transmission are analyzed. The dynamics of epidemic models are globally investigated by using Floquet theory and comparison theorem of impulsive differential equation. Thresholds are identified and global stability results are proved. For every treatment and vaccination strategy, the disease-free periodic solution of impulsive system has been obtained and is found to be globally asymptotically stable when the basic reproduction number is less than one, equivalently the cure rate is larger than the threshold value, whereas the disease is persistent when the basic reproduction number is larger than one. These results indicate that a large cure rate will lead to the eradication of a disease.