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771.
I. Yavari H. Mostafavi D. Tahmassebi R. Hekmat-Shoar 《Monatshefte für Chemie / Chemical Monthly》1997,128(6-7):675-679
Summary Cyclic 1,3-diketones like cyclopentane-1,3-dione, cyclohexane-1,3-dione, and 5,5-dimethylcyclohexane-1,3-dione react with 1,8-diaminonaphthalene to afford new condensed heterocyclic spiro systems.
Kondensation von 1,3-Diketonen mit 1,8-Diaminonaphthalin: Synthese vonBis(2,3-dihydroperimidin-2-spiro)cycloalkanen
Zusammenfassung Cyclische 1,3-Diketone wie Cyclopentan-1,3-dion, Cyclohexan-1,3-dion und 5,5-Dimethylcyclohexan-1,3-dion reagieren mit 1,8-Diaminonaphthalin zu neuen kondensierten heterocyclischen Spiranen.相似文献
772.
The thermoanalytical curves of (C6H5)4AsCl (I) and (C6H5)4PCl (II) were generated simultaneously by using a Netzsch simultaneous thermal analyser 409 under static air and dynamic argon atmospheres. The ranges of thermal stability of I and II were found to be 145–310°C and 137–365°C, respectively, and their melting points to be 261 and 278°C. The DTA profiles of I and II differ and can be used for their distinction. 相似文献
773.
Daniela Mizusaki Iyomasa Ivania Garavelo Mamie Mizusaki Iyomasa Ii-sei Watanabe Jo?o Paulo Mardegan Issa 《Micron (Oxford, England : 1993)》2009,40(4):413-418
Low level laser therapy (LLLT) is known for its positive results but studies on the biological and biomodulator characteristics of the effects produced in the skeletal muscle are still lacking. In this study the effects of two laser dosages, 5 or 10 J/cm2, on the lesioned tibial muscle were compared. Gerbils previously lesioned by 100 g load impact were divided into three groups: GI (n = 5) controls, lesion non-irradiated; GII (n = 5), lesion irradiated with 5 J/cm2 and GIII (n = 5), lesion irradiated with 10 J/cm2, and treated for 7 consecutive days with a laser He–Ne (λ = 633 nm). After intracardiac perfusion, the muscles were dissected and reduced to small fragments, post-fixed in 1% osmium tetroxide, dehydrated in increasing alcohol concentrations, treated with propylene oxide and embedded in Spurr resin at 60 °C. Ultrafine cuts examined on a transmission electron microscope (Jeol 1010) revealed in the control GI group a large number of altered muscle fibers with degenerating mitochondria, intercellular substance containing degenerating cell fragments and budding blood capillaries with underdeveloped endothelial cells. However, groups GII and GIII showed muscle fibers with few altered myofibrils, regularly contoured mitochondria, ample intermembrane spaces and dilated mitochondrial crests. The clean intercellular substance showed numerous collagen fibers and capillaries with multiple abluminal processes, intraluminal protrusions and several pinocytic vesicles in endothelial cells. It was concluded that laser dosages of 5 or 10 J/cm2 delivered by laser He–Ne (λ = 633 nm) during 7 consecutive days increase mitochondrial activity in muscular fibers, activate fibroblasts and macrophages and stimulate angiogenesis, thus suggesting effectivity of laser therapy under these experimental conditions. 相似文献
774.
Polyaniline (PANI)-chemically coated the electrode of quartz-crystal microbalance (QCM) has been developed for the determination of phosphoric acid (H3PO4) in the liquid phase. The sensing mechanism is based on the fact that the QCM devices produce a change in the oscillating frequency when the PANI coating the electrode of QCM interacts with different concentration of the acid. This was made during the subsequent redoping–dedoping processes of the PANI film in acid and ammonia solutions, respectively. Also, this was made during the successive redoping in different acid solutions. The QCM sensor demonstrated a rapid response to the acid with an excellent reversibility. A linear response of the sensor for different concentrations of H3PO4 was found in region of 1 M. The conductivity at different concentration of the acid was also determined. Finally, pH dependence on the electronic absorption of PANI phosphate film was studied which indicates that the film can be used as a sensor over a wider pH range of 3–12. This is in comparison to a PANI-sulphate film which shows limited pH absorption dependence (5–8). 相似文献
775.
Salim Al-Harthi Mubarak Al-Saadi Imad Al-Omari Husein Sitepu Khalid Melghit Issa Al-Amri Ashraf T. Al-Hinai Senoy Thomas 《Applied Physics A: Materials Science & Processing》2010,99(1):237-244
We report on the analysis of morphology and electronic structure of Fe3+-doped Zn–TiO2 nanoparticles. Crystalline nature, phase, and preferred growth direction of the nanoparticles were all determined. Due to
size effects and OH−–(TiO4)
n
complexes, variation in the energy gap with metallic and semiconducting characters on the same sample was found. The variation
in the energy gap decreased, and the bang gap decayed exponentially with Fe doping and independent of the supporting substrates.
Simultaneous effect of the OH− ligands on the electronic structure and the formation mechanism of nanorods and nanosheets as manifested by the rutile TiO6 octahedra units edge- and corner-shared bonding was discussed. 相似文献
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780.
M. Ahmadi R. Yavari A. Y. Faal H. Aghayan 《Journal of Radioanalytical and Nuclear Chemistry》2016,310(1):177-190