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51.
Shiu-Jen Liu Shih-Hao Su Jenh-Yih Juang 《Applied Physics A: Materials Science & Processing》2014,116(3):1473-1476
Room-temperature ferromagnetism (RTFM) was observed in pulsed-laser deposited amorphous In–Ga–Zn–O (a-IGZO) films undoped with impurities containing unpaired d or f electrons. The presence of oxygen vacancies in the prepared a-IGZO films was verified by X-ray photoelectron spectroscopy and suggested to be responsible for the observed RTFM. The electrical and optical properties of the a-IGZO films were also investigated. 相似文献
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53.
Ching Hsuan Lin Chu Ming Huang Meng Wei Wang Shenghong A. Dai Hou Chien Chang Tzong Yuan Juang 《Journal of polymer science. Part A, Polymer chemistry》2014,52(3):424-434
A new phosphinated acetoxybenzoic acid, 1‐(4‐acetoxyphenyl)‐1‐(4‐carboxylphenyl)‐1‐(6‐oxido‐6H‐dibenz<c,e><1,2> oxaphosphorin‐6‐yl)ethane (3), was prepared by a three‐step procedure. Phosphinated copolyesters based on the acidolysis and polycondensation of (3) with poly(ethylene terephthalate) (PET) were prepared. The crystallinity of copolyesters decreased gradually with the content of (3), as shown in wide‐angle X‐ray diffractograms and differential scanning calorimetry thermograms. Dynamic mechanical analysis and thermal mechanical analysis show Tg increased with the content of (3). UL‐94 flame retardant test shows that the flame resistance of PET was enhanced with the content of (3), and a copolyester with UL‐94 V‐0 grade can be achieved with a phosphorus content as low as 1.43 wt %. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 424–434 相似文献
54.
Adsorption of tannic acid, humic acid, and dyes from water using the composite of chitosan and activated clay 总被引:37,自引:0,他引:37
Chitosan is a well-known excellent adsorbent for a number of organics and metal ions, but its mechanical properties and specific gravity should be enhanced for practical operation. In this study, activated clay was added in chitosan slurry to prepare composite beads. The adsorption isotherms and kinetics of two organic acids (tannic acid, humic acid) and two dyes (methylene blue, reactive dye RR222) using composite beads, activated clay, and chitosan beads were compared. With composite beads as an adsorbent, all the isotherms were better fitted by the Freundlich equation. The adsorption capacities with composite beads were generally comparable to those with chitosan beads but much larger than those with activated clay. The pseudo-first-order and pseudo-second-order equations were then screened to describe the adsorption processes. It was shown that the adsorption of larger molecules such as tannic acid (MW, 1700 g mol(-1)), humic acid, and RR222 from water onto composite beads was better described by the pseudo-first-order kinetic model. The rate parameters of the intraparticle diffusion model for adsorption onto such adsorbents were also evaluated and compared to identify the adsorption mechanisms. 相似文献
55.
From the methanolic extract of the leaves of Planchonella duclitan, 2α,3α,19α,23‐tetrahydroxy‐13,27‐cyclours‐11‐en‐28‐oic acid (1), myrianthic acid (2), 2‐hydroxyursolic acid (3), ursolic acid (4), pomolic acid (5), rotundic acid (6), and jacoumaric acid (7) were isolated, and their structures were elucidated on the basis of their spectroscopic analysis. Among them, compound 1 was a new cyclopropyl ursane‐type triterpene acid. Additionally, compounds 4 and 7 showed significant cytotoxicity toward human colorectal carcinoma cell line HT29 and human breast carcinoma cell line MCF‐7 with IC50 values ranging from 5.8 ± 1.4 to 6.5 ± 1.9 μM. 相似文献
56.
The anilinepentacyanoferrate (II) complex has been characterized in aqueous solution. The complex exhibits a predominant ligand field transition at λmax = 415 nm with ?max = 494 M?1 cm?1. The corresponding Fe(III) complex displays a strong absorption at λmax = 700nm(?max = 1.61×104 M?1 sec?1) which can be assigned as a ligand to metal charge transfer transition. The rate constants of formation and dissociation for the Fc(II) complex are (3.14±0.18)×102 M?1W?1 and 0.985±0.005 sec?1, respectively, at μ = 0.10 M LiClO4, pH = 8 and T = 25°C. The cyclic voltammetry of the complex shows that a reversible redox process is observed with E1/2 value of 0.51±0.01 V vs. NHE at μ = 0.10 M LiClO4, pH = 8 and T = 25°C. The kinetic study of the oxidation of the Fe(II) complex by ferricyanide ion yielded the rate constant of the reaction ket = (1.43±0.04)x10 M sec?1 at μ = 0.10 M LiClO4, pH = 8 and T = 25°C. 相似文献
57.
Der-Fong Juang Chao-Hsien Lee Shu-Chun Hsueh Huei-Yin Chou 《Applied biochemistry and biotechnology》2012,167(4):714-731
Two microbial fuel cells (MFCs) inoculated with activated sludge of a wastewater treatment plant were constructed. Oxygen was provided by mechanical aeration in the cathodic chamber of one MFC, whereas it was obtained by the photosynthesis of algae in the other. Electrogenic capabilities of both MFCs were compared under the same operational conditions. Results showed that the MFC with mechanical aeration in the cathodic chamber displayed higher power output than the one with photosynthesis of algae. Good linear relationship between power density and chemical oxygen demand (COD) loading rate was obtained only on the MFC with mechanical aeration. Furthermore, the relationships between power density and effluent COD and between Coulombic efficiency and COD loading rate can only be expressed as binary quadratic equations for the MFC with mechanical aeration and not for the one with photosynthesis of algae. 相似文献
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59.
Chondrocytes are the only cell type present in mature articular cartilage (2-5% of total tissue). The biological activities of the chondrocyte population are regulated by genetic, biologic and biochemical factors, as well as environmental factors (stress, flow and electric field). Although compressive forces within joint articular cartilage are required for maintenance of the normal composition of articular cartilage, there is a lack of knowledge about the number of pressure-related proteins expressed in articular cartilage. Two-dimensional gel electrophoresis (2-DE) and high-performance liquid chromatography-electrospray/tandem mass spectrometry (HPLC/ESI-MS/MS) were used to identify the levels of pressure-related proteins expressed by chondrocytes grown in the presence or absence of hydrostatic pressure. A total of 266 spots were excised from the gels and analyzed by HPLC/ESI-MS/MS. Functional classification of up-regulated proteins indicated that energy and protein fate were the main biological processes occurring in pressurized chondrocytes. Furthermore, membrane-bound transferrin-like protein p97, a marker of chondrocyte differentiation, was only expressed in chondrocytes under hydrostatic pressure. These data suggest that hydrostatic pressure can induce cell differentiation by increasing the expression level of energy metabolism- and protein fate-related proteins, indicating that hydrostatic pressure may be needed for normal biosynthesis and differentiation of articular chondrocytes. 相似文献
60.
In this work, we introduce the concept of cone ball-metric spaces and we prove fixed point results on such spaces for mappings satisfying a contraction involving a stronger Meir-Keeler cone-type function. 相似文献