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101.
在不锈钢电极(SS)表面制得超细纤维状聚苯胺(superfine-fibrous PANI),经Pt微粒修饰后得到Pt微粒超细纤维聚苯胺复合电极[Pt/(superfine-fibrous PANI)/SS]。结果表明,直径50-100nm的Pt微粒均匀分布于直径约100nm的聚苯胺纤维上;Pt/(superfine-fibrous PANI)/SS电极对H2O2氧化具有很好的电催化活性。采用脉冲电流法(PGM)再将葡萄糖氧化酶(GOD)与间苯二胺(MPD)混合共聚嵌于Pt/(superilnefibrous PANI)/SS电极表面,获得了具有优异生物电化学传感特性的葡萄糖氧化酶电极。该酶电极最大响应电流密度im=917.4μA/cm^2,米氏常数K=9.339mmol/L;酶电极对葡萄糖响应快,对尿酸和抗坏血酸有很好的抗干扰性能。 相似文献
102.
Chemical composition and biological activities of essential oil from Filifolium sibiricum (L.) Kitam
Shanshan Liang Qing Wei Juan Xue Yichun Sun Zhili Chen Haixue Kuang 《Natural product research》2016,30(24):2861-2863
The essential oil from Filifolium sibiricum (L.) Kitam were extracted using hydrodistillation and GC-MS was used to analyse the essential oil. The main components were espatulenol (8.55%), geranyl acetate (8.03%), caryophyllene oxide (5.47%), calamenene (4.79%), geraniol (4.28%), calamenene (4.53%), geraniol (4.06%), cedrene epoxide (3.23%), myrtenol (3.18%), transgeranylgeranio (3.13%), etc. The essential oil showed intensive inhibitory effects against MCF-7 with IC50 level of 0.78 mg/mL, HepG-2 with IC50 level of 0.44 mg/mL, SKOV-3 with IC50 level of 0.27 mg/mL, BGC-823 with IC50 level of 0.34 mg/mL. In the antibacterial test, the essential oil showed the significant antibacterial activities. The MIC and MBC values were 5.20 and 5.20 mg/mL against Staphylococcus aureus. 相似文献
103.
Kim SN Kuang Z Slocik JM Jones SE Cui Y Farmer BL McAlpine MC Naik RR 《Journal of the American Chemical Society》2011,133(37):14480-14483
Peptides identified from combinatorial peptide libraries have been shown to bind to a variety of abiotic surfaces. Biotic-abiotic interactions can be exploited to create hybrid materials with interesting electronic, optical, or catalytic properties. Here we show that peptides identified from a combinatorial phage display peptide library assemble preferentially to the edge or planar surface of graphene and can affect the electronic properties of graphene. Molecular dynamics simulations and experiments provide insight into the mechanism of peptide binding to the graphene edge. 相似文献
104.
Phase relationships in the BaO-Ga(2)O(3)-Ta(2)O(5) ternary system at 1200 °C were determined. The A(6)B(10)O(30) tetragonal tungsten bronze (TTB) related solution in the BaO-Ta(2)O(5) subsystem dissolved up to ~11 mol % Ga(2)O(3), forming a ternary trapezoid-shaped TTB-related solid solution region defined by the BaTa(2)O(6), Ba(1.1)Ta(5)O(13.6), Ba(1.58)Ga(0.92)Ta(4.08)O(13.16), and Ba(6)GaTa(9)O(30) compositions in the BaO-Ga(2)O(3)-Ta(2)O(5) system. Two ternary phases Ba(6)Ga(21)TaO(40) and eight-layer twinned hexagonal perovskite solid solution Ba(8)Ga(4-x)Ta(4+0.6x)O(24) were confirmed in the BaO-Ga(2)O(3)-Ta(2)O(5) system. Ba(6)Ga(21)TaO(40) crystallized in a monoclinic cell of a = 15.9130(2) ?, b = 11.7309(1) ?, c = 5.13593(6) ?, β = 107.7893(9)°, and Z = 1 in space group C2/m. The structure of Ba(6)Ga(21)TaO(40) was solved by the charge flipping method, and it represents a three-dimensional (3D) mixed GaO(4) tetrahedral and GaO(6)/TaO(6) octahedral framework, forming mixed 1D 5/6-fold tunnels that accommodate the Ba cations along the c axis. The electrical property of Ba(6)Ga(21)TaO(40) was characterized by using ac impedance spectroscopy. 相似文献
105.
R. Bernabei P. Belli F. Montecchia W. Di Nicolantonio G. Ignesti A. Incicchitti D. Prosperi C. J. Dai L. K. Ding H. H. Kuang J. M. Ma 《Physics letters. [Part B]》1999,450(4):40
The results achieved with a statistics of 14962 kg·day, collected with the large mass highly radiopure DAMA NaI(Tl) set-up, are described and investigated in terms of WIMP annual modulation signature. A maximum likelihood analysis of these data, combined with the statistics of 4549 kg·day previously published (total statistics of 19511 kg·day), favours the hypothesis of presence of an annual modulation at 99.6% C.L. 相似文献
106.
107.
108.
Yan Li Xinru Jia Min Gao Hai He Guichao Kuang Yen Wei 《Journal of polymer science. Part A, Polymer chemistry》2010,48(3):551-557
Gn (n = 3, 4, and 5) poly(amidoamine) (PAMAM) dendrimers were synthesized and peripherally modified with photocleavable o‐nitrobenzyl (NB) groups by reacting o‐nitrobenzaldehyde with the terminal amine groups of PAMAM dendrimers, followed by reducing the imine to amine groups with NaBH4. The NB‐modified dendrimers, Gn‐NB (n = 3, 4, and 5), were characterized by nuclear magnetic resonance and fourier transform infrared spectroscopy. The results showed that the NB groups were successfully attached on the periphery of the dendrimers with near 100% grafting efficiency. Such a photosensitive NB shell could be cut off on irradiation with 365 nm ultraviolet (UV) light. The encapsulation and release of guest molecules, that is, salicylic acid (SA) and adriamycin (ADR), by Gn‐NB were explored. The encapsulation capability of these dendrimers was found to increase as the guest molecular size was decreased and have dependence on the generation of dendrimers as well. For both of SA and ADR, the average encapsulation numbers per dendrimer decreased in the order of G4‐NB > G5‐NB > G3‐NB, indicating that the fourth generation dendrimer was a better container for the guest molecules. The rate of SA release was found to be greater with UV irradiation than that without, suggesting that the NB‐shelled PAMMAM dendrimers could function as a molecular container/box with photoresponsive characteristics. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 551–557, 2010 相似文献
109.
Chong-Xing Yue Hua Wang Yu-Ping Kuang Gong-Ru Lu 《Zeitschrift fur Physik C Particles and Fields》1997,76(1):133-135
TC(technicolor) corrections to tt? production in high-energy photon-photon collision are calculated in the topcolor-assisted multiscale technicolor(TOPCMTC) model. We find that the contribution of the technipions to the production cross section of the process γγ → tt? is very small. The relative corrections to the production cross section mainly come from the top-pions, which may be observable at future e + e -. linear collider. 相似文献
110.
本文在文献[1]和[2]的基础上,将改进型三角形广义协调元TGC-9-1应用于薄板振动和稳定分析中。推导出带有一个内部自由度(外部结点有九个自由度)的三角形板单元的协调质量矩阵和几何刚度矩阵。并通过算例表明,改进型广义协调三角形单元(TGC-9-1)具有良好的性态和更好的精度,程序简便。 相似文献