Electron spin relaxation time of Ni(II) ion in hexapyrazole zinc(II) dinitrate at 300 K

Understanding the electron spin relaxation properties of paramagnetic species is a fundamental requirement to use them as a probe to measure distances between sites in biomolecules by electron paramagnetic resonance (EPR) spectroscopy. Even though Ni(II) ion is an essential trace element for many species, relaxation properties are not well understood. Herein, the polycrystalline sample of Ni(II) ion magnetically diluted in Zn(Pyrazole)₆(NO₃)₂ (Ni/ZPN) has been studied in detail by EPR spectroscopy to explore the electron spin relaxation time. Progressive continuous-wave (CW) EPR power saturation study on Ni/ZPN at 300 K yielded 907 mW as the P_1/2 value. The cavity constant (K_Q) has been calculated using tempol in PVA-BA glass matrix and the product of electron spin-lattice relaxation time (T₁) and spin–spin relaxation time (T₂) for Ni/ZPN at 300 K has been reported for the first time.     

Influence of temperature and mobile phase composition on retention properties of oligomeric bonded phases in reversed-phase liquid chromatography (RPLC)

Summary The effect of temperature and mobile phase composition (methanol-water) on the retention behaviour of an oligomeric series of n-octylsilyl bonded phases in reversed-phase liquid chromatography has been investigated. Plots of lnk against 1/T (van't Hoff plot) and the enthalpy of transfer (ΔH^o) yields linear relationships under the conditions studied. The ΔH^o values of the aromatic hydrocarbons and n-alkyl benzoates are higher than those of the polar compounds due to their higher level of interaction with the stationary phase. A linear plot of ΔH^o vs. ΔS^o suggest that the retention process, which is essentially controlled by non-specific (dispersive) interactions between the solutes and the bonded ligands, is identical for all cases evaluated. The existence of similar retention mechanisms is confirmed by the constant value of the enthalpy-entropy compensation temperature of the columns for a given class of componds. As expected, decreasing the methanol content (% v/v) of the mobile phase results in increased eluite retention times. The methylene and phenyl selectivities are found to be independent of the carbon content of the stationary phases and varied only with the eluent composition. In addition to their high stability under aggressive mobile phase conditions as previously reported, the results of this study generally showed that the solute retention process on oligomeric phases are similar to those exhibited by the conventional reversed phases.     

钠离子电池钴酸钠正极材料研究进展

钠离子电池凭借分布广泛和低成本的钠资源在大规模电化学能量存储领域受到广泛关注. 层状过渡金属氧化物作为一种重要的钠离子电池正极材料, 具有比容量高、电化学可逆性相对较好和化学组成丰富且可调的特征, 得到广泛关注. 其中钴酸钠是一种典型层状过渡金属氧化物, 自20世纪80年代就得到大量研究. 由于钴酸钠含有丰富的电化学信息, 基于其充放电过程进行的机理研究对理解钠离子电池层状氧化物体系具有重要意义. 因此在介绍钴酸钠的常见结构类型与合成相图的基础上, 本文着重综述了不同结构钴酸钠在充放电过程中结构变化和电荷补偿机理的研究进展, 同时讨论了上述机制对电化学性能的影响. 本综述旨在为深入研究并建立层状过渡金属氧化物正极材料电化学过程中的构效关系提供支持.     

Trends in the International Regime of Liability and Compensation for Oil Pollution Damage

Since the entry into force of the International Convention on liability and compensation for oil spill damage, there have been many discussions on the improvement of this regime. Based on the existing two regimes, the writer tried to analysis the advantages of the new regimes and foresee the trends of the international regime of liability and compensation for oil pollution damage.     

金融侵权行为认定及惩处探讨

金融侵权行为是一种特殊的行业性侵权行为，必须依法认定金融机构的储蓄侵权行为、借贷侵权行为、贷款欺诈行为、证券欺诈行为、票据欺诈行为等。公民、法人因多事侵权行为而遭受损害的，有权依法索赔。金融机构及其工作人员的侵权行为触犯法律规定的，还必须依法追究单位和个人的行政责任或刑事责任。     

自卑感与补偿

从个体心理学的角度探讨人的自卑感与补偿心理，认为自卑感是个体的一种情绪状态－心境，产生于个体的生活经验，可以从人的外部行为进行观察。补偿是由自卑感所引起的、通过一定的行为方式及效果所获得的心理满足或平衡，因此它与自卑感是一种心理现象的两个方面。个体最基本的补偿是正确补偿与错误补偿，教育的作用之一应当引导个体寻求正确的补偿。     

电化学体系中非连续型振荡的诱发

根据非连续型振动与慢流型，双稳态现象之间的内在联系，讨论了演化机制可出现多定态分支的电极反应体系，因外控状态参量慢变化导致非连续型电化学振荡的可能性。模型研究表明，适当的外电路阻抗或反应体系温度控制的热补偿机制的存在，可能诱发该类振荡，从而为抑制或诱发利用该类振荡提供了一条可能的途径。     

Investigation of changes in properties of water under the action of a magnetic field

The properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecular and atomic structures of water. It was found that some properties of water were changed, and a lot of new and strange phenomena were discovered after magnetization. Magnetized water really has magnetism, which has been verified by a peak shift of X-ray diffraction of magnetized water + Fe₃O₄ hybrid relative to that of pure water + Fe₃O₄ hybrid, that is a saturation and memory effect. The properties of infrared and ultraviolet absorptions, Raman scattering and X-ray diffraction of magnetized water were greatly changed relative to those of pure water; their strengths of peaks were all increased, the frequencies of some peaks did also shift, and some new peaks, for example, at 5198, 8050 and 9340 cm⁻¹, occurred at 25°C after water was magnetized. In the meanwhile, the magnetized effects of water are related to the magnetized time, the intensity of an externally applied magnetic field, and the temperature of water, but they are not a linear relationship. The study also showed a lot of new and unusual properties of magnetized water, for example, the six peaks in 3000–3800 cm⁻¹ in infrared absorption, the exponential increase of ultraviolet absorption of wave with the decreasing wavelength of light of 200–300 nm, the frequency-shifts of peaks, a strange irreversible effect in the increasing and decreasing processes, as well as a stronger peak of absorption occurring at 50°C, 70°C and 80°C, the existence of many models of motion from 85°C to 95°C in 8000–10000 cm⁻¹, and so on. These results show that the molecular structure of water is very complicated, which needs further study. Furthermore, the macroscopic feature of mechanics, for instance, surface tension force of magnetized water, was also measured. Experiments discovered that the size in contact angles of magnetized water on the surface of hydrophobic materials decreases, thus the surface tension force of magnetized water decreases relative to that of pure water. It is seen from the above results that the clustering structure of hydrogen-bonded chains and polarization effects of water molecules are enhanced after magnetization. These results are helpful in revealing the mechanism of magnetization of water. Supported by the National Basic Research Program of China (Grant No. 2007CB936103)     

孔隙介质中气体相变超声波测试方法研究

依据孔隙介质中的弹性波理论,以CO2气体为对象,研究了无介质和有孔隙介质两种情况下气体相态转变的超声波测试新方法。结果表明:超声波声速和衰减对CO2气体相变敏感;而孔隙介质可能一定程度地影响了CO2气体的相行为,既改变其饱和蒸汽压,也减缓其相变的突变程度。这种超声波方法有望进一步发展为研究孔隙介质中凝析气相行为的新测试技术。     

A comparative study of interaction of ibuprofen with biocompatible polymers

In this paper we are reporting the interaction of a non-steroidal anti-inflammatory drug ibuprofen (IBF) with various biocompatible polymers. Being amphiphilic, the drug interacts with the polymers similar to the interaction of surfactants and polymers. Therefore, we have considered the polymer-amphiphile interaction approach using conductimetry. The polymers of different charges (cationic, anionic, and nonionic) have been taken for the study. It was found that the critical aggregation concentration (cac) decreases on increasing the polymer concentrations of cationic as well as nonionic polymers whereas it increases for anionic polymers. The results imply that anionic IBF interacts with cationic and nonionic polymers more strongly as compared to the anionic polymers. A possible anionic-anionic repulsion is responsible for the weak interaction of IBF with anionic polymers. On the other side, the critical micelle concentration (cmc) increases for all polymers which is a usual indication of the interaction between amphiphiles and polymers. Free energies of aggregation (ΔG_agg) and micellization (ΔG_mic) were also computed with the help of degrees of micelle ionization obtained from the specific conductivity - [IBF] isotherms.