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161.
Tarek Abu‐Husein Swen Schuster Martin Kind Tobias Santowski Adrian Wiesner Ryan Chiechi Egbert Zojer Andreas Terfort Michael Zharnikov 《Advanced functional materials》2015,25(25):3943-3957
Using a representative model system, here electronic and structural properties of aromatic self‐assembled monolayers (SAMs) are described that contain an embedded, dipolar group. As polar unit, pyrimidine is used, with its orientation in the molecular backbone and, consequently, the direction of the embedded dipole moment being varied. The electronic and structural properties of these embedded‐dipole SAMs are thoroughly analyzed using a number of complementary characterization techniques combined with quantum‐mechanical modeling. It is shown that such mid‐chain‐substituted monolayers are highly interesting from both fundamental and application viewpoints, as the dipolar groups are found to induce a potential discontinuity inside the monolayer, electrostatically shifting the core‐level energies in the regions above and below the dipoles relative to one another. These SAMs also allow for tuning the substrate work function in a controlled manner independent of the docking chemistry and, most importantly, without modifying the SAM‐ambient interface. 相似文献
162.
163.
液晶电视时序控制器(T-CON)中颜色校正表的自动生成方法 总被引:1,自引:0,他引:1
针对液晶电视时序控制器T-CON (Timing Controller)中影响图像显示的色彩参数调试过程繁琐、效率低问题,根据平板电视色度学原理使用VC++编程实现了颜色校正表的自动生成,利用MSChart控件和截屏函数实现了色度坐标曲线的自动生成和保存功能.自动调试方法较传统手工调试有较大改进,效率大大提高、通用性强和色度坐标曲线一致性好.缩短了时序控制器的开发周期,改善了液晶电视图像的显示效果. 相似文献
164.
Abstract We report a molecular dynamics study on the 1:1 M3+ lanthanide (La3+, Eu3+ and Yb3+) inclusion complexes of an important extractant molecule L: a calix[4]arene-tetraalkyl ether substituted at the wide rim by four NH-C(O)-CH2-P(O)Ph2 arms. The M(NO3)3 and MCl3 complexes of L are compared in methanol solution and at a water / chloroform interface. In the different environments the coordination sphere of M3+ involves the four phosphoryl oxygens and three to four loosely bound carbonyl oxygens of the CMPO-like arms. Based on free energy simulations, we address the question of ion binding selectivity in pure liquid phases and at the liquid-liquid interface where L and the complexes are found to adsorb. According to the simulations, the enhancement of M3+ cation extraction in the presence of the calixarene platform, examined by comparing L to the (CMPO)4 “ligand” at the interface, is related to the fact that (i) the (CMPO)4Eu(NO3)3 complex is more hydrophilic than the LEu(NO3) one and (ii) the free CMPO ligands spread at the interface, and are therefore less organized for cation capture than L. 相似文献
165.
We present a comparative study on the C-H stretching vibrations at air/DMSO (dimethyl sulfoxide) interface with both the free-induction decay (FID) coherent vibrational dynamics and the sub-wavenumber high resolution sum-frequency generation vibrational spectroscopy measurements. In principle the frequency-domain and time-domain spectroscopic measurements should generate identical information for a given molecular system. However, when the molecular systems are with several coupled or overlapping vibrational modes, obtain- ing detailed spectroscopic and coherent dynamics information is not as straightforward and rather difficult from either the time-domain or the frequency domain measurements. For the case of air/DMSO interface that is with moderately complex vibrational spectra, we show that the frequency-domain measurement with sub-wavenumber high-resolution sum-frequency generation vibrational spectroscopy is probably more advantageous than the time- domain measurement in obtaining quantitative understanding of the structure and coherent dynamics of the molecular interface. 相似文献
166.
Sivasankar Reddy Akepati Chadrasekhar Loka Ho Tak Yu Kee‐Sun Lee 《Surface and interface analysis : SIA》2013,45(9):1419-1423
As‐deposited Ag(10 nm)/glass films exhibited agglomerated nanocrystals with seemingly thick boundaries. Introduction of a TaNx layer below the Ag films resulted in dense and smooth structures, with a resistance at least three times lower than that of Ag/glass. For TaNx(10 nm)/Ag(10 nm)/TaNx(10 nm)/glass multilayer films, Auger electron spectroscopy results indicate that TaNx acts as an effective barrier restraining the diffusion of Ag. After annealing (up to 573 K), no outward diffusion of Ag through either TaNx layer was seen. However, partial oxidation of the outermost TaNx layer to form Ta2O5 was observed. The films showed promising optical properties with 73% transmittance in the visible region and ~15% average transmittance in the near‐infrared region. The optical data obtained here was in good agreement with simulated predictions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
167.
Zhi-Gang Feng 《Journal of Dispersion Science and Technology》2013,34(7):968-974
The hydrodynamics of a sphere with interface slip has been numerically investigated for flows of Reynolds number ranging 0 < Re ≤ 75. A simple correlation of the drag force coefficient in the present of interface slip has been derived based on our numerical simulations. The correlation takes the slip coefficient and Reynolds number as two input parameters. By comparing results found in the literature, we believe that the present correlation is more accurate; it provides a source for future experiment study and for numerical simulations of large multi-particle system where the interface slip is important. 相似文献
168.
Xu-Long Cao 《Journal of Dispersion Science and Technology》2013,34(10):1321-1325
The effect of octadecanol on dilational properties of 4,5-diheptyl-2-propylbenzene sulfonate and partly hydrolyzed polyacrylamide at the decane-water interface has been examined by means of longitudinal method. The octadecanol plays different roles in influencing the structure of adsorbed layers at different bulk concentration. A small quantity of octadecanol may enhance the dilational modulus by forming densely packed mixed-adsorption layer with surfactant molecules through hydrophobic interaction, which leads to the increase of dilational modulus. However, due to the weakening of the “entanglement” among long alkyl chains in surfactant molecules by the intercalation of octadecanol, the superfluous addition of octadecanol could decrease the dilational modulus. In the case of polymer/octadecanol system, the addition of the polymer may enhance the dilational modulus due to the slow diffusion-exchange process of the polymer. 相似文献
169.
Tianqing Liu Yinyin Gan Lilia Song Jing Qiu Liuhua Chen 《Journal of Dispersion Science and Technology》2013,34(10):1370-1375
Vesicles have been prepared at a constant molar ratio of L-glutamic acid/1-aminodecane/ibuprofen/H2O. The fusion dynamics of the vesicles have been directly observed and followed by using optical microscopy and freeze fracture replication-electron microscopy technologies. With time increasing up to 25 minutes, the vesicles slowly fuse to form large stable vesicles. A membrane phase transition temperature is detected at 97°C. 相似文献
170.
Qianping Ran Ponisseril Somasundaran Changwen Miao Jiaping Liu Shishan Wu Jian Shen 《Journal of Dispersion Science and Technology》2013,34(6):790-798
Comb polymers are commonly used as dispersants to stabilize highly concentrated cement suspensions. The effectiveness of such polymeric additives to stabilize these suspensions is determined to a large extent by the amount adsorbed. In this study we investigated the adsorption characteristics of various comb dispersant containing different graft densities on surfaces of cement particle. The effect of inorganic salts on their adsorption was also examined in order to elucidate their adsorption mechanism. The results show that the adsorption of comb polymer dispersants on cement surface conforms approximately to Langmuir's adsorption isotherm and the characteristic plateau A s and adsorption free energy ΔGads are largely dependent on the anionic group content of the comb polymers. The A s and ΔGads increase with increasing anionic group content. This information suggests that the adsorption of comb polymers on cement surfaces is dominated by electrostatic interaction between COO-groups on the comb polymers and the positive surface of the cement. This conclusion is supported by effects of inorganics such as calcium and sulfate ions, and diffuse reflectance FTIR spectroscopy. The implication of results for tuning polymers for the required performance in cement manufacture should be noted. 相似文献