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81.
Jian‐Je Chen Quoc‐Phong Ho Meng‐Jiy Wang 《Journal of Polymer Science.Polymer Physics》2012,50(7):484-491
The incorporation of biological function into synthetic polymers provides particular potential for advances in studying the complex interactions between biomolecules and materials. We developed a simple method to create polymer with submicron features on surface of polystyrene‐co‐maleic anhydride (PSMAA) using a combination of phase‐separation and spin coating method. The nanostructured PSMAA which was rarely utilized as biomaterials was further functionalized by doping with dopamine or by treating with nitrogen containing plasma. This study demonstrated a straightforward method that the creation of topographical cues alone improves the biocompatibility of PSMAA thin film. The cell proliferation increased more significantly to ~1.8‐ and 2.5‐fold on dopamine blended and N2/H2 plasma treated PSMAA films when compared to that on the flat sample, respectively. The overall results showed that the integration of microenvironment and chemical functionalities into materials provide promising effects for promoting mammalian cell growth. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献
82.
Dr. Luong Phong Ho Angelika Neitzel Dr. Thomas Bannenberg Prof. Dr. Matthias Tamm 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(4):e202104139
The lithium salts of anionic N-heterocyclic thiones and selones [{(WCA-IDipp)E}Li(toluene)] ( 1 : E=S; 2 : E=Se; WCA=B(C6F5)3, IDipp=1,3-bis(2,6-diisopropylphenyl)imidazolin-2-ylidene), which contain a weakly coordinating anionic (WCA) borate moiety in the imidazole backbone were reacted with Me3SiCl, to furnish the silylated adducts (WCA-IDipp)ESiMe3 ( 3 : E=S; 4 : E=Se). The reaction of the latter with [(η5-C5Me5)MCl2]2 (M=Rh, Ir) afforded the rhodium(III) and iridium(III) half-sandwich complexes [{(WCA-IDipp)E}MCl(η5-C5Me5)] ( 5 – 8 ). The direct reaction of the lithium salts 1 and 2 with a half or a full equivalent of [M(COD)Cl]2 (M=Rh, Ir) afforded the monometallic complexes [{(WCA-IDipp)E}M(COD)] ( 9 – 12 ) or the bimetallic complexes [μ2-{(WCA-IDipp)E}M2(COD)2(μ2-Cl)] ( 13 – 16 ), respectively. The bonding situation in these complexes has been investigated by means of density functional theory (DFT) calculations, revealing thiolate or selenolate ligand character with negligible metal-chalcogen π-interaction. 相似文献
83.
Tomohiko Inagaki Le Thanh Phong Akihiro Furuta Jun‐ichi Ito Assist. Prof. Dr. Hisao Nishiyama Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(10):3090-3096
Chiral bis(oxazolinylphenyl)amines proved to be efficient auxiliary ligands for iron and cobalt catalysts with high activity for asymmetric hydrosilylation of ketones and asymmetric conjugate hydrosilylation of enones. 相似文献
84.
D. Q. Thuyet K. Yamazaki T. K. Phong H. Watanabe D. T. T. Nhung K. Takagi 《Journal of Analytical Chemistry》2010,65(8):843-847
A method for the determination of imidacloprid in paddy water and soil was developed using liquid chromatography electrospray
ionization-tandem mass spectrometry (LC/ESI-MS/MS). Separation of imidacloprid was carried out on a Shimadzu C18 column (150 mm × 4.6 mm, 4.6 μm) with an acetonitrile-water
(50: 50, v/v) mobile phase containing 0.1% of acetic acid. The flow rate was 0.3 mL/min in isocratic mode. The product ion
at 209 m/z was selected for quantification in multiple-reaction monitoring scan mode. Imidacloprid residues in soil were extracted by
a solid-liquid extraction method with acetonitrile. Water samples were filtered and directly injected for analysis without
extraction. Detection limits of 0.5 μg/kg and 0.3 μg/L were achieved for soil and water samples, respectively. The method
had recoveries of 90 ± 2% (n = 4) for soil samples and 100 ± 2% (n = 4) for water samples. A linear relationship was observed throughout the investigated range of concentrations (1–200 μg/L),
with the correlation coefficients ranging from 0.999 to 1.000. 相似文献
85.
We study the chance-constrained vehicle routing problem (CCVRP), a version of the vehicle routing problem (VRP) with stochastic demands, where a limit is imposed on the probability that each vehicle’s capacity is exceeded. A distinguishing feature of our proposed methodologies is that they allow correlation between random demands, whereas nearly all existing exact methods for the VRP with stochastic demands require independent demands. We first study an edge-based formulation for the CCVRP, in particular addressing the challenge of how to determine a lower bound on the number of vehicles required to serve a subset of customers. We then investigate the use of a branch-and-cut-and-price (BCP) algorithm. While BCP algorithms have been considered the state of the art in solving the deterministic VRP, few attempts have been made to extend this framework to the VRP with stochastic demands. In contrast to the deterministic VRP, we find that the pricing problem for the CCVRP problem is strongly \(\mathcal {NP}\)-hard, even when the routes being priced are allowed to have cycles. We therefore propose a further relaxation of the routes that enables pricing via dynamic programming. We also demonstrate how our proposed methodologies can be adapted to solve a distributionally robust CCVRP problem. Numerical results indicate that the proposed methods can solve instances of CCVRP having up to 55 vertices. 相似文献
86.
87.
Taro Fukaya Hiroko Watando Shinetsu Fujieda Shioko Saya Cao Minh Thai Masaaki Yamamoto 《Polymer Degradation and Stability》2006,91(11):2549-2553
We have found that a reheating process for the products in the chemical recycling of rigid polyurethane foam by an extruder with diethanolamine as a decomposing agent is effective for improving the product stability. The product with stable viscosity was obtained by the reheating process at 175-200 °C for 2 h, regardless of the extruding condition. An amine adduct, which is an intermediate, was found to be the cause of instability of the discharged product from the extruder. At the initial stage of reheating, the intermediate decomposed, releasing toluenediamine, which promoted further decomposition of the discharged products. We have succeeded in controlling the quality of the recycled products. 相似文献
88.
Numerical analysis to predict turning characteristics of rigid suspension tracked vehicle 总被引:7,自引:0,他引:7
Numerical analysis was developed to calculate the steering properties of a rigid suspension tracked vehicle turning on soft terrain. The developed numerical analysis is based on a method to solve a set of non-linear equations. To verify the numerical analysis, an experiment on a model-tracked vehicle turning with a steering ratio of 1.6 on a loose sandy terrain was carried out. The comparison between measured and calculated values shows that the numerical analysis can predict sinkage, slip ratios and turning radius within an error amount of 15%. 相似文献
89.
All those complex valued multiplicative functions f and g are characterized for which g(n + k) – f(n) 0 (n ) is satisfied (k is an arbitrary nonzero integer). 相似文献
90.
Vu Quoc Phong 《Proceedings of the American Mathematical Society》2001,129(10):2871-2879
We prove that if is a -semigroup on a Hilbert space , then (a) if and only if , for all , and (b) is exponentially stable if and only if , for all . Analogous, but weaker, statements also hold for semigroups on Banach spaces.