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941.
The nanostructure of a biomaterial surface has strong influence on cell behavior. The migration of cells on nanostructured surfaces, however, has not been investigated so far. In this study, we used PCL/PEG diblock copolymers as model surfaces to examine the effect of nanoislands on migration of different cells, including fibroblasts and endothelial cells. The water sliding angle of the substrates was measured. The cell migration rate was examined under a real-time optical microscope. It was found that a greater cell migration rate correlated with the smaller sliding angle of the substrate. 相似文献
942.
Yan‐Fu Chen Chang‐Long Kao Jyun‐Fu Yang Ping‐Chih Huang Ching‐Yun Hsu Chun‐Hsiung Kuei 《中国化学会会志》2015,62(9):766-771
A simplified extraction method was developed for extracting high molecular weight polycyclic aromatic hydrocarbons (PAHs) from river sediments. The samples were extracted 3 times with 5 mL of solvent (toluene:methanol, 9 : 1, v/v) at 100 °C, 10 minutes for each extraction. After clean‐up and concentration, extracts were analyzed by gas chromatography coupled with mass spectrometer (GC‐MS). The extraction efficiency and accuracy was evaluated by the standard reference material (SRM‐1941b). Comparing to certified values, the average recoveries of high molecular weight PAHs with 3, 4, 5 and 6 fused benzene rings were 72.9∼113.2 % (R.S.D. 2.3∼6.3 %) except those of dibenz[a,h]anthracene (206.2±4.6 %). The average recoveries for PAHs spiked sediment samples were comparable with accelerated solvent extraction (ASE) and Soxhlet methods. The simple extraction method consumes less solvent, fewer amount of sample than those of conventional methods. The lowest quantitation limit of PAHs is 1.1 μg/kg. 相似文献
943.
Extraction of Intercalated O2 from Aligned Carbon Nanotubes: The Breaking of Intertube Paths and Exponential Changes in Resistance 下载免费PDF全文
Hsin Jung Tsai Wen Yi Lin Wei Chin Tsung Ying Tsai Prof. Wen Kuang Hsu 《Chemphyschem》2015,16(12):2625-2629
In carbon nanotube films, the alignment of carbon nanotubes creates Lennard–Jones potentials at intertube junctions and trapped O2 appears to oscillate at elevated temperatures. Electrical measurements reveal a low hopping barrier along the transverse direction and an underlying mechanism that involves intercalated molecules acting as charge carriers between tubes. Ab initio calculations support dynamic intercalation and charge transfer through O2 bouncing between tubes. 相似文献
944.
Hung-Chu Hsu 《Journal of Mathematical Fluid Mechanics》2014,16(3):463-471
We present an exact solution of the nonlinear governing equations for internal geophysical water waves propagating westward in the f-plane approximation near the equator. We show that the mass transport velocity induced by this internal equatorial wave is eastward. 相似文献
945.
The optical system lens temperature difference will cause optical aberration increase. This study is applying finite element method (FEM) and optical ray tracing; calculate off axis ray thermal optical path difference (OPD). The optical system temperature distribution is calculated from finite element simulation result and weighting temperature to each optical ray path. The simulation result shows off-axis ray major thermal optical aberrations are tilt and piston at this study. 相似文献
946.
A synthesis of fully substituted cyclopentanes bearing a quaternary carbon center and five contiguous stereogenic centers has been achieved by sequential organocatalyzed Stetter and Michael-Aldol reactions of heteroaromatic aldehydes, nitroalkenes, and α,β-unsaturated aldehydes via the [1 + 2 + 2] annulation strategy with dynamic kinetic asymmetric transformation and excellent enantioselectivities (up to >99% ee). 相似文献
947.
This paper presents a mathematical study for the Bragg scattering of water waves propagating over a series of rectangular poro-elastic submerged breakwaters. Based on the linear wave theory and the improved Biot's theory of poro-elastic media with suitable matching conditions, an analytical solution was obtained as a function of elasticity, permeability and geometry of the submerged breakwaters. Experiments were also conducted in a wave flume to verify the present analytical study. In addition, the Bragg resonances for different influence parameters were studied. Satisfactory agreement between the theoretical predictions and the laboratory observations demonstrates the applicability of the present analytical result. 相似文献
948.
This paper considers some scheduling problems with deteriorating jobs. The objectives are to minimize the makespan, the total completion time, the total absolute deviation of completion time, the earliness, tardiness, and due date penalty, the sum of earliness penalties subject to no tardy jobs, respectively. We also explore two resource constrained scheduling problems: how to minimize the resource consumption with makespan constraints and how to minimize the makespan with the total resource consumption constraints. Several polynomial time algorithms are proposed to optimally solve the problems with the above objective functions. 相似文献
949.
The relationships between the Hurst exponent H and the power-law scaling exponent B in a new modification of sandpile models, i.e. the long-range connective sandpile (LRCS) models, exhibit a strong dependence upon the system size L. As L decreases, the LRCS model can demonstrate a transition from the negative to positive correlations between H- and B-values. While the negative and null correlations are associated with the fractional Gaussian noise and generalized Cauchy processes, respectively, the regime with the positive correlation between the Hurst and power-law scaling exponents may suggest an unknown, interesting class of the stochastic processes. 相似文献
950.
S.-Y.?Huang T.-C.?Tung C.-L.?Ting H.-C.?Jau M.-S.?Li H.-K.?Hsu A.?Y.-G.?FuhEmail author 《Applied physics. B, Lasers and optics》2011,104(1):93-97
This work demonstrates the feasibility of a microlens array (MLA) with a focal intensity that can be optically tuned by controlling
the polarization of incident light. The proposed MLA has a focusing unit based on birefringent liquid crystalline polymer
(LCP) and a tuning unit with a photo-alignment layer for controlling the polarization state of incident laser light. The optically
variable refractive indices of LCP allow a positive or negative MLA to be realized by controlling the polarization of the
incident light. 相似文献