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991.
Four stereoisomers of Phytophthora mating hormone α2 were synthesized using both enantiomers of citronellol as starting materials. The absolute configuration of the natural product was determined to be 7S,11R,15R by oospore-inducing assays of the synthetic isomers. A concise synthetic procedure of α1 was also established using a common synthetic intermediate of α2. 相似文献
992.
Josef Buršík Ivo Drbohlav Zdeněk Frait Karel Kní?ek Radomír Ku?el Karel Kou?il 《Journal of solid state chemistry》2011,184(11):3085-3094
Thin films of SrFe12O19 (SrM) were prepared from a solution of iron and strontium alkoxides through the chemical solution deposition method on both amorphous (glassy SiO2), and single crystal substrates (Si(100), Si(111), Ag(111), Al2O3(001), MgO(111), MgAl2O4(111), SrTiO3(111)) substrates. The process of crystallization was investigated by means of powder diffraction, atomic force microscopy and scanning electron microscopy. Magnetization measurements, ferromagnetic and nuclear magnetic resonance were used for evaluation of anisotropy in the films. Whilst amorphous substrates enabled growth of randomly oriented SrM phase, use of single crystal substrates resulted in samples with different degree of oriented growth. The most pronounced oriented growth was observed on SrTiO3(111). A detailed inspection revealed that growth of SrM phase starts through the breakup of initially continuous film into isolated grains with expressive shape anisotropy and hexagonal habit. A continuous film with epitaxial relations to the substrate was produced by repeating recoating and annealing. 相似文献
993.
Wu H Kou F Jia F Liu B Yuan J Bai Y 《Journal of photochemistry and photobiology. B, Biology》2011,105(3):190-197
A six-coordinate copper(II) complex with the ligand 1,3-bis(1-methylbenzimidazol-2-yl)-2-oxopropane (Meobb), with composition [Cu(Meobb)(2)](NO(3))(2)·2CH(3)OH, has been synthesized and characterized by elemental analysis, electrical conductivities, IR, UV-Vis spectral measurements. A study of the electro-chemistry of the copper(II) complex was carried out by using cyclic voltammetry. The molecular structures of the ligand Meobb and the Cu(II) complex were determined by X-ray crystal diffraction. The DNA-binding modes of the ligand and the complex were investigated by electronic absorption titration, ethidium bromide-DNA displacement experiments and viscosity measurements. The experimental evidence indicated the compounds interact with calf thymus DNA through intercalation. Additionally, the Cu(II) complex exhibited potential antioxidant properties in in vitro studies. 相似文献
994.
Jun-Feng Su Sheng-Bao Wang Jian-Wei Zhou Zhen Huang Yun-Hui Zhao Xiao-Yan Yuan Yun-Yi Zhang Jin-Bao Kou 《Colloid and polymer science》2011,289(2):169-177
Microcapsules containing phase change materials (microPCMs) have many potential applications because of their thermoregulation
or thermosaving abilities. At the same time, it is still essential to understand the interface stability of microPCMs/polymer
composites during a thermal transmission. The aim of this work was to fabricate novel microPCMs containing dodecanol by an
in situ polymerization using methanol-modified melamine–formaldehyde (MMF) prepolymer as shell material and investigate the
interface morphologies of microPCMs/epoxy composites treated by a simulant thermal process with a ten times repeated temperature
variation. A series of microPCMs were fabricated by 1,000–3,000 r·min−1 emulsion speed with the PCM contents of 40–70%. The average diameter, melting temperature, and encapsulation efficiency of
microPCMs were 1–16 μm, 19.5 °C, and 97.4%, respectively. Tests results indicated that the properties of the microPCMs were
greatly affected by core/shell ratios and emulsification stirring rates of preparation conditions. With the increasing of
stirring rates, the average diameters of microPCMs were sharply decreased. The encapsulation efficiency (E
e) values of microPCMs increased with the increasing of stirring rates. The contents of PCM in microcapsules (C
t) and the average diameter of microPCMs both affected the interface morphologies of microPCMs/epoxy composites after the repeated
thermal treatments. Microcracks and gaps occurred after a thermal treatment in the interface of microPCMs and epoxy matrix
obviously. The internal stress generated by the expansion or shrinking of the microPCMs was the main factor leading to the
interface morphology changes and damaged of composites. 相似文献
995.
Hui-Lu Wu Jing-Kun Yuan Ying Bai Fei Jia Bin Liu Fan Kou Jin Kong 《Transition Metal Chemistry》2011,36(8):819-827
Bis(N-allylbenzimidazol-2-ylmethyl)benzylamine (babb) and two of its complexes, [Cu(babb)(pic)2]·H2O (1) and [Co(babb)2](pic)2 (2) (pic = picrate), have been synthesized and characterized by physico-chemical and spectroscopic methods. Single crystal X-ray
diffraction revealed that the two complexes have similar distorted octahedral structures, but the degree of distortion and
the coordinated atoms are different. The DNA-binding properties of the free ligand and its two complexes have been investigated
by electronic absorption, fluorescence, and viscosity measurements. The results suggest that all three compounds bind to DNA
via an intercalative binding mode, and their binding affinity for DNA follows the order 2 > 1 > ligand. Additionally, both complexes exhibited potential antioxidant properties in in vitro studies, and complex 1 was the more effective. 相似文献
996.
997.
Tetranuclear [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](ClO(4))(2)·2py (1), [Ni(4)(Hpzaox)(2)(pzaox)(2)(py)(4)](NO(3))(2)·4py (2), and two-dimensional (2D) [Ni(4)(Hpzaox)(2)(pzaox)(2)(H(2)O)(2)](NO(3))(2)·2H(2)O (3) are prepared via the reaction of NiX(2)·6H(2)O and pyrazine-2-amidoxime (H(2)pzaox). All compounds contain [Ni(4)(Hpzaox)(2)(pzaox)(2)](2+) fragments, which assemble to form a tetranuclear or polymeric network. Magnetic studies show that the tetranuclear compounds display usual ferromagnetic coupling via the oxime N-O bridges, and the 2D compound displays unusual antiferromagnetic behavior. 相似文献
998.
Xu K Chen H Tian J Ding B Xie Y Qiang M Tang B 《Chemical communications (Cambridge, England)》2011,47(33):9468-9470
BzSe-Cy is a small-molecule fluorescent probe containing Se, which can respond reversibly to changes in ONOO(-) or reduced ascorbate and exhibit high sensitivity and selectivity for ONOO(-). 相似文献
999.
A weak polyelectrolyte coating, carboxylated poly(oligo(ethylene glycol)methacrylate-co-2-hydroxyethylmethacrylate), was prepared via surface initiated polymerization (SIP) from initiators immobilized to gold surface through the Au-S bonds. When dry thickness increased up to 75 nm, this polyelectrolyte coating was pulled off the Au substrate by simply exposing to phosphate buffer saline (PBS, pH = 7.4, [Na(+)] = 150 mM). This covalent bond breaking (CBB) behavior was monitored in situ using a quartz crystal microbalance (QCM) and CBB was associated with the swelling of the anchored polyelectrolyte chains. 相似文献
1000.
Tests of consistency for the pair-wise comparison matrices have been studied extensively since AHP was introduced by Saaty in 1970s. However, existing methods are either too complicated to be applied in the revising process of the inconsistent comparison matrix or are difficult to preserve most of the original comparison information due to the use of a new pair-wise comparison matrix. Those methods might work for AHP but not for ANP as the comparison matrix of ANP needs to be strictly consistent. To improve the consistency ratio, this paper proposes a simple method, which combines the theorem of matrix multiplication, vectors dot product, and the definition of consistent pair-wise comparison matrix, to identify the inconsistent elements. The correctness of the proposed method is proved mathematically. The experimental studies have also shown that the proposed method is accurate and efficient in decision maker’s revising process to satisfy the consistency requirements of AHP/ANP. 相似文献