Hepatoprotective action of Radix Paeoniae Rubra aqueous extract against CCl4-induced hepatic damage

In the present study the capacity of Radix Paeoniae Rubra aqueous extract (RPRAE) as an antioxidant to protect against carbon tetrachloride (CCl(4))-induced oxidative stress and hepatotoxicity in Wistar rats was investigated. Six groups of rats were used. Radix Paeoniae Rubra aqueous extract (100 or 200 or 300 mg/kg of bw) or bifendate (100 mg/kg of bw) were given daily by gavage to the animals on 28 consecutive days to elucidate the protective effects against CCl(4)-induced hepatotoxicity. The 20% CCl(4)/olive oil was gavage of gastric tube twice a week (on the third and seventh days of each week). The animals of normal control group were given only vehicle. The animals of CCl(4)-treated group were administered with CCl(4) twice a week (on the third and seventh days of each week) and with vehicle on rest of the days. The test materials were found effective as hepatoprotective agents, as evidenced by plasma and liver biochemical parameters. Therefore, the results of this study show that Radix Paeoniae Rubra aqueous extract can protect the liver against CCl(4)-induced oxidative damage in rats, and the hepatoprotective effects might be correlated with its antioxidant and free radical scavenger effects.     

离子色谱法测定葡萄酒中的高氯酸盐

建立了离子色谱测定红酒中高氯酸盐的分析方法。以4种葡萄酒为典型样品,测定了其中的高氯酸盐含量。使用Metrosep A Supp5阴离子分析柱（150 mm×4.0 mm）进行分离,柱温为40℃,流动相为1.0 mmol/L碳酸钠水溶液-丙酮（85：15,v/v）,流速为0.8 mL/min。结果表明,高氯酸盐在0.1~10 mg/L内具有良好的线性关系,相关系数为0.9998,方法回收率大于86.0%,相对标准偏差小于2.6%。该方法前处理方便快捷、检测灵敏度高,可满足红酒中高氯酸盐含量的测定。     

Synthesis,Crystal Structure and Vibrational Spectroscopy of NH4[Co(NH3)5(H2O)][B4O5(OH)4]2·6H2O

A novel hydrated cobalt tetraborate complex NH₄[Co(NH₃)₅(H₂O)][B₄O₅(OH)₄]₂·6H₂O, was synthesized by the reaction of NH₄‐borate aqueous with CoCl₂ and its structure was determined by single crystal X‐ray diffraction. The crystal system of this complex is orthorhombic, the space group is Pnma, and the unit cell parameters are a=1.2901(2) nm, b=1.6817(3) nm, c=1.1368(2) nm, α=β=γ=90°, V=2.4742(8) nm³, and Z=4. This compound contains infinite borate layers constructed from [B₄O₅(OH)₄]^2? units via hydrogen bonds. The adjacent polyborate anion layers are further linked together with the octahedral [Co(NH₃)₅(H₂O)]³⁺ groups through hydrogen bonds to form 3D framework. The groups and guest water molecules are deposited in the empty space of this framework and interact with the layers by extensive hydrogen bonds. Infrared and Raman spectra (4000–400 cm^?1) of NH₄[Co(NH₃)₅(H₂O)][B₄O₅(OH)₄]₂·6H₂O were recorded at room temperature and analyzed. Fundamental vibrational modes were identified and band assignments were made. The middle band observed at 575 cm^?1 in Raman spectrum is the pulse vibration of [B₄O₅(OH)₄]^2?.     

聚乙烯中炭黑含量不同测试方法的探讨

采用GB 13021《聚乙烯管材和管体炭黑含量测定(热失重法)》和热重分析仪法两种方法测定了聚乙烯中炭黑含量。对两种方法的测定结果进行了比较,结果表明,两种方法均有良好的重复性和准确度,测定结果基本一致,采用不同方法得到的测定结果间可以相互参考。     

流动分析法同时测定铬（Ⅵ）及铬（Ⅲ）过程中铈（Ⅳ）氧化剂的影响

以Ｃｅ（Ⅳ）为氧化剂，采用流动分析在线氧化技术，实现了对Ｃｒ（Ⅵ）和Ｃｒ（Ⅲ）的同时在线分析，发现Ｃｅ（Ⅳ）氧化剂在测定过程中产生负干扰，在而Ｃｒ（Ⅲ）存在时会使Ｃｒ（Ⅵ）的测定结果偏高，本文提出了一个校正模型，通过数学方法消除上述干扰，所建立的分析方法对Ｃｒ（Ⅵ）和Ｃｒ（Ⅲ）分析的平均相对误差不大于６．５％。     

Preparation and properties of water‐absorbent composites of chloroprene rubber,starch, and sodium acrylate

The effects of the amounts of starch, sodium acrylate (NaAA) and dicumyl peroxide (DCP) on the properties of chloroprene rubber (CR)/starch/NaAA composites prepared by melting method were investigated. The results showed that the addition of starch improved the mechanical properties, but decreased the water‐absorbing capacity of the composite, most likely due to the decrease in the local concentration of the main water‐absorbing material sodium polyacrylate and the increase in crosslinking density of the composite resulting from the reaction between starch and CR. This reaction was verified by the vulcanized curves, DSC curves, and the cut surface morphology. The as‐prepared composite demonstrated higher water‐absorbing capacity, resulting from the incorporation of NaAA. The mechanical properties decreased with increasing the DCP loading, and the water‐absorbing ratio is the maximum at 1.0 phr DCP. The tensile strength of the composite decreased significantly after water immersion, due to the absorbed water acting as a plasticizer. The extracted component from composites after water immersion is mainly sodium polyacrylate according to Fourier transform infrared (FT‐IR) spectroscopy analysis. The morphology of the composites before and after water immersion was observed by optical transmission microscopy (OTM). The results indicated that the starch exhibits a good dispersion state, and the water‐absorbing capacity results primarily from sodium polyacrylate. Copyright © 2010 John Wiley & Sons, Ltd.     

Real‐Time Atomic‐Scale Visualization of Reversible Copper Surface Activation during the CO Oxidation Reaction

By using in situ aberration‐corrected environmental transmission electron microscopy, for the first time at atomic level, the dynamic evolution of the Cu surface is captured during CO oxidation. Under reaction conditions, the Cu surface is activated, typically involving 2–3 atomic layers with the formation of a reversible metastable phase that only exists during catalytic reactions. The distinctive role of CO and O₂ in the surface activation is revealed, which features CO exposure to lead to surface roughening and consequently formation of low‐coordinated Cu atoms, while O₂ exposure induces a quasi‐crystalline CuOx phase. Supported by DFT calculations, it is shown that crystalline CuOx reversibly transforms into the amorphous phase, acting as an active species to facilitate the interaction of gas reactants and catalyzing CO oxidation.     

Enantiomeric Discrimination by Surface‐Enhanced Raman Scattering–Chiral Anisotropy of Chiral Nanostructured Gold Films

A surface‐enhanced Raman scattering‐chiral anisotropy (SERS‐ChA) effect is reported that combines chiral discrimination and surface Raman scattering enhancement on chiral nanostructured Au films (CNAFs) equipped in the normal Raman scattering Spectrometer. The CNAFs provided remarkably higher enhancement factors of Raman scattering (EFs) for particular enantiomers, and the SERS intensity was proportional to the enantiomeric excesses (ee) values. Except for molecules with mesomeric species, all of the tested enantiomers exhibited high SERS‐ChA asymmetry factors (g), ranging between 1.34 and 1.99 regardless of polarities, sizes, chromophores, concentrations and ee. The effect might be attributed to selective resonance coupling between the induced electric and magnetic dipoles associated with enantiomers and chiral plasmonic modes of CNAFs.     

New Host Molecules with Imidazoliums as Functional Arms:Syntheses and Anion Recognition

The bridged tri-imidazoliums 3.3X^--5.3X^-(X^-=PF6^-,Br^-,I^-)and bis-imidazoliums 6.2PF6^- were synthesized by N-quaternization of imidazole derivative 1 in acetonitrile under reflux.UV spectroscopic titration experiments showed that the halide salts and hexafluorophosphate salts of these imidazoliums exhibited good recognition toward anions in water and in acetonitrile,respectively.     

A lead(II) sensor based on a glassy carbon electrode modified with Fe3O4 nanospheres and carbon nanotubes

We have developed a highly sensitive and selective sensor for lead(II) ions. A glassy carbon electrode was modified with Fe₃O₄ nanospheres and multi-walled carbon nanotubes, and this material was characterized by scanning electron microscopy and X-ray diffraction. The electrode displays good electrochemical activity toward Pb(II) and gives anodic and cathodic peaks with potentials at ?496 mV and ?638 mV (vs. Ag/AgCl) in pH?6.0 solution. The sensor exhibits a sensitive and fairly selective response to Pb(II) ion, with a linear range between 20 pM and 1.6 nM, and a detection limit as low as 6.0 pM (at a signal-to noise ratio of 3). The sensor was successfully applied to monitor Pb(II) in spiked water samples.