18C6 AND DC18C6 CROWN-ETHERS AS SYNERGIC AGENTS IN THE EXTRACTION OF Co(II) AND Ni(I) FROH CHLORIDE MEDIA WITH 1-PHENYL.-3-HETHIL.-4-BENZOYLPYRAZOL.-5-ONE IN TOLUENE

The synergic extraction of Co(ll) and Ni(Il) with 1-phenyl-3-methyl-4-benzoylpyrazol-5-one (HPMBP) in presence of crown-ether (Cw) 18C6 or DC18C6 (cis-syn-cis and cis-anti-cis isomers) in toluene from 1M chloride medium is quantitatively described. A slope analysis of the distribution curves shows that the composition of the extracted species depends on the cations found in the aqueous solution : from a LiCl or (CH₃.)NC1₄ solution, the extracted species are M(PMBP) ₂.Cw (M = Co, Ni) whereas the KCw⁺,M(PMBP)₃ ion pair is extracted from 1M KC1 solution. In the two cases, higher D-values in extraction with DC18C6 are only due to a poorer lipophilicity of 18C6; both ethers are weaker synergists than lipophilic ammonium salts.     

新型磷酸二酯酶Ⅳ抑制剂Ariflo 对内皮素-1诱发离体人子宫平滑肌收缩的影响

目的:研究选择性磷酸二酯酶(phosphodiesterase, PDE) Ⅳ抑制剂Ariflo 对内皮素-1 (endothelin-1,ET-1)诱发的非妊娠人子宫平滑肌收缩的影响。方法:累积给药法观察药物对离体平滑肌收缩的作用。结果:Ariflo 可降低子宫平滑肌自主收缩的收缩频率及收缩幅度(pD₂ =7.90), 且对ET-1 (3 ×10^-8 mol·L^-1)诱发的子宫平滑肌收缩具有浓度依赖性抑制作用(pD₂ =7.40), 作用强度与Rolipram 相似。结论:Ariflo 对ET-1 诱发的离体人子宫平滑肌的收缩具有显著抑制作用, 提示在临床上有缓解痛经的作用。     

An experimental investigation on oil mist characterization used in MQL milling process

In this study, a method is developed to determine the oil mist characteristics for the minimal quantity lubricant process. The oil mist is characterized by the size, velocity, and volume flow rate of its particles. In each case, a specific measurement process is used: the laser diffraction granulometry method, the particle image velocimetry, and the gravimetric method. These methods are used in the case of static and simple models with different inner channels. Experimental tests have been done with the same inner channel as the existing spindle inner channel. Different output models with different inner canalizations have been tested, using these experimental processes. The main goal is to control the characteristics of output oil mist as a function of the input oil mist device parameters.     

Microwave Methods and Systems for Nondestructive Control

In the past the use of network analyzersfor measuring the electrical properties of materialsmakes the microwave techniques unsuitable for industrial purposes. Butrecently much attention has been paid to the development of microwave systems dedicated to the nondestructive testing of materials. In general these apparatus are designed for a given applicationso the cost in comparison with the network analyzer is considerably lower. The aim of this paper is to present results obtained from utilizing various configurations of original S-Parameters Measurement System (SPMS) constructed for practical use.     

Resistance of stainless steel CHS columns based on cross-section deformation capacity

A conceptually new structural design approach has recently been proposed by the authors to predict the resistance of stainless steel members subjected to various types of loading with cross-sections formed from thin flat plates including angles, channels, lipped channels, I-sections and rectangular hollow sections (RHS). The proposed method does not follow the traditional cross-section classification approach, which primarily relies on the assumption of a bilinear, elastic-perfectly-plastic material model. Instead, deformation capacity of a cross-section is determined directly from the local buckling characteristics of the constituent plate elements. This is then used to obtain the corresponding local buckling stress utilising an appropriate material model. This basic concept is extended herein to predict compression resistance of stainless steel columns with circular hollow sections (CHS). Available test and finite element (FE) results have been used to develop the basic design equation to predict the compression resistance of cross-sections and to propose column curves to determine flexural buckling resistances. The predicted resistances have been compared to those obtained using the current Eurocode; the predictions are significantly more accurate and more consistent than those given by the existing Eurocode.     

Reversible electron-transfer reactions within a nanoscale metal oxide cage mediated by metallic substrates

Transition metal oxides exhibit a rich collection of electronic properties and have many practical applications in areas such as catalysis and ultra-high-density magnetic data storage. Therefore the development of switchable molecular transition metal oxides has potential for the engineering of single-molecule devices and nanoscale electronics. At present, the electronic properties of transition metal oxides can only be tailored through the irreversible introduction of dopant ions, modifying the electronic structure by either injecting electrons or core holes. Here we show that a molybdenum(VI) oxide 'polyoxometalate' molecular nanocluster containing two embedded redox agents is activated by a metallic surface and can reversibly interconvert between two electronic states. Upon thermal activation two electrons are ejected from the active sulphite anions and delocalized over the metal oxide cluster cage, switching it from a fully oxidized state to a two-electron reduced state along with the concomitant formation of an S-S bonding interaction between the two sulphur centres inside the cluster shell.     

A microsatellite map of wheat

Hexaploid bread wheat (Triticum aestivum L. em. Thell) is one of the world's most important crop plants and displays a very low level of intraspecific polymorphism. We report the development of highly polymorphic microsatellite markers using procedures optimized for the large wheat genome. The isolation of microsatellite-containing clones from hypomethylated regions of the wheat genome increased the proportion of useful markers almost twofold. The majority (80%) of primer sets developed are genome-specific and detect only a single locus in one of the three genomes of bread wheat (A, B, or D). Only 20% of the markers detect more than one locus. A total of 279 loci amplified by 230 primer sets were placed onto a genetic framework map composed of RFLPs previously mapped in the reference population of the International Triticeae Mapping Initiative (ITMI) Opata 85 x W7984. Sixty-five microsatellites were mapped at a LOD >2.5, and 214 microsatellites were assigned to the most likely intervals. Ninety-three loci were mapped to the A genome, 115 to the B genome, and 71 to the D genome. The markers are randomly distributed along the linkage map, with clustering in several centromeric regions.     

High-resolution proton,carbon-13 and nitrogen-15 nuclear magnetic resonance studies of wheat proteins at high magnetic fields: Spectral assignments,changes with concentration and heating treatments of flinor gliadins in solution—comparison with gluten spectra

The first high-field and high-resolution proton, carbon-13 and nitrogen-15 nuclear magnetic resonance (n.m.r.) spectra of gliadin solutions are reported. Collective assignments are proposed based on ‘random coil’ chemical shifts and amino acid analysis of gliadins. Additional information from X-ray diffraction, photoacoustic spectroscopy, dielectric relaxation and electrophoretic measurements is considered in the interpretation of the n.m.r. spectra. Marked changes in the n.m.r. spectra of gliadin solution were observed with increasing concentration or temperature. An interpretation of these effects in molecular terms is proposed and the practical implications of n.m.r. measurements for wheat variety identification and correlation with rheological testing indicated. The relevance of the results to studies of glutens is also noted.