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61.
Thermally reversible light scattering (TRLS) films are prepared from ultraviolet (UV) curing of polyether urethane diacrylate (PEUDA) with dispersed low molecular weight 1-octadecanol (OD). Depending on the temperature, the OD domains are crystalline or amorphous and this produce opaque or transparent films in a reversible way. Stable optically transparent and light scattering states are obtained after 100 successive heating–cooling cycles. Moreover, morphologies of the OD domains could be varied significantly with the cure temperature and this led to notable discrepancy in optical properties. By using an UV-mask and curing in two steps at different temperatures, complex patterns could be recorded in the film that were encoded at high temperatures (60 °C) and revealed at low temperatures (i.e., at room temperature), which makes the film a candidate for thermo-optical recording medium. 相似文献
62.
63.
A new 3d–4f heterometallic coordination framework, {[Eu(ox)(H2O)4] · [CuBr(2‐pzc)2] · 4H2O} ( 1 ) [ox = oxalate; 2‐pzc = pyrazine‐2‐carboxylate] was synthesized and characterized by elemental analysis, IR spectroscopy and thermal analysis, as well as single‐crystal X‐ray diffraction. Complex 1 represents one 3D supramolecular heterometallic coordination framework that is assembled from rare lanthanide‐ox anionic chains and CuBr(2‐pzc)2 cationic units through hydrogen bonds. 相似文献
64.
Electrodeposition of Mg with Zn in acidic sulfate solutions with polyethylene glycol and octadecyl dimethyl benzyl ammonium
chloride as additives was investigated by scanning electron microscopy, X-ray diffraction, and potentiodynamic polarization
techniques. The results show that these two compounds act in a synergetic way to suppress Zn deposition markedly and facilitate
Mg reduction. Zn–0.46%Mg coatings are produced under high cathodic current densities, which have lower corrosion potentials
than Zn coatings and hydrogen evolution in neutral chloride solutions. Magnesium hydroxide may cause current oscillations
at high cathodic polarizations in plating solutions without zinc salts due to its formation and peel-off. An “induced co-deposition”
mechanism is proposed for Zn–Mg alloy electrodeposition. 相似文献
65.
Yunsheng Xue Jie Mou Yi Liu Xuedong Gong Yihua Yang Lin An 《Central European Journal of Chemistry》2010,8(4):928-936
The electronic absorption spectra of 29 phenyl-ring substituted chalcones have been investigated with the time-dependent density
functional theory (TD-DFT) and polarizable continuum TD-DFT (PCM-TD-DFT). It turns out that the hybrid PBE1PBE functional
with the 6-31G basis set provide reliable λmax when the solvent effects are included in the model. Comparisons with experimental values lead to a mean absolute error of
12 nm (0.136 eV). Moreover, the observed substituent effects are reproduced by calculation qualitatively. The λmax of substituted chalcone in phenyl ring A is less sensitive to substitution than that in ring B. The linear correlation of
Hammett’s substituent constants (σP) with LUMO energies is better with respect to HOMO energies. The calculation reveals that the maximum absorption band mainly
results from the π→π* transition from HOMO to LUMO. The analysis of the electron density plots of frontier molecular orbitals
show that most transitions should be of valence excitation nature.
相似文献
66.
We report an all-fiber mode-locked erbium-doped fiber laser (EDFL) employing carbon nanotube (CNT) polymer composite film. By using only standard telecom grade components, without any complex polarization control elements in the laser cavity, we have demonstrated polarization locked vector solitons generation with duration of ~583 fs, average power of ~3 mW (pulse energy of 118 pJ) at the repetition rate of ~25.7 MHz. 相似文献
67.
Yuanyi Cao Shaolei Wang Haiyan Mou Haiyan Xu Chifei Wu 《Journal of Crystal Growth》2010,312(10):1747-1750
Crystal growth of a hindered phenol compound, tetrakis [methylene-3-(3-5-ditert-butyl-4-hydroxy phenyl) propionyloxy] methane (trade name AO-60), was successfully recorded by optical microscopy (OM) equipped with a hot stage. The morphology of AO-60 crystals, grown at 100 °C from amorphous state, appeared in the form of tetragonal-sloped step growth. Further study using scanning electron microscopy (SEM) and atomic force microscopy (AFM) experimentally demonstrated that AO-60 crystals had a hopper-like morphology, which had occurred rarely in the condition of organic compound crystals but predominantly rather to inorganic compound crystals in the reported literatures. The morphological features observed on the crystal surfaces suggested step growth and hopper growth mechanism. Besides, a raising around the edge of the AO-60 hopper crystal was also experimentally characterized for the first time. 相似文献
68.
Xue Jing Yanga Ya Ling Yang Wei Zhenb Mou Sheng Liua Jun Hong Chaia a Faculty of Life Science Technology Kunming University of Science Technology Kunming China b Kunming Fruit Business Economics Co.Ltd. Kunming China 《中国化学快报》2009,20(4)
An modified laminar crystal sodium silicate(A1-SKS-6) was synthesized by spray drying and high temperature crystallization using sodium silicate as silicon source,Al atom as inorganic source and hexadecyltrimethy ammonium bromide(CTMAB) as the structure template.The hydrothermal stability of product was at least 1 h.The synthesized material was characterized by XRD and SEM.The results indicated that shape and intensity of XRD diffraction peak at 2θtook changes,but raw materialδphase crystal form kept unc... 相似文献
69.
Libin Mou 《Archive for Rational Mechanics and Analysis》1994,127(3):199-217
It is proved that a harmonic map with small energy and the monotonicity property is smooth if its singular set is rectifiable and has a finite uniform density; moreover, the monotonicity property holds if the singular set has a lower dimension or its gradient has higher integrability. This work generalizes the results in [CL, DF, LG12], which were proved under the assumption that the singular sets are isolated points or smooth submanifolds. 相似文献
70.
Christian Wenz Coral Barbas Ángeles López‐Gonzálvez Antonia Garcia Fernando Benavente Victoria Sanz‐Nebot Tim Blanc Gordon Freckleton Philip Britz‐McKibbin Meera Shanmuganathan Francois de l′Escaille Johann Far Rob Haselberg Sean Huang Carolin Huhn Martin Pattky David Michels Si Mou Feng Yang Christian Neusuess Nora Tromsdorf Edward E.K. Baidoo Jay D. Keasling SungAe Suhr Park 《Journal of separation science》2015,38(18):NA-NA
A collaborative study on the robustness and portability of a capillary electrophoresis‐mass spectrometry method for peptide mapping was performed by an international team, consisting of 13 independent laboratories from academia and industry. All participants used the same batch of samples, reagents and coated capillaries to run their assays, whereas they utilized the capillary electrophoresis‐mass spectrometry equipment available in their laboratories. The equipment used varied in model, type and instrument manufacturer. Furthermore, different types of sheath‐flow capillary electrophoresis–mass spectrometry interfaces were used. Migration time, peak height and peak area of ten representative target peptides of trypsin‐digested bovine serum albumin were determined by every laboratory on two consecutive days. The data were critically evaluated to identify outliers and final values for means, repeatability (precision within a laboratory) and reproducibility (precision between laboratories) were established. For relative migration time the repeatability was between 0.05 and 0.18% RSD and the reproducibility between 0.14 and 1.3% RSD. For relative peak area repeatability and reproducibility values obtained were 3–12 and 9–29% RSD, respectively. These results demonstrate that capillary electrophoresis‐mass spectrometry is robust enough to allow a method transfer across multiple laboratories and should promote a more widespread use of peptide mapping and other capillary electrophoresis‐mass spectrometry applications in biopharmaceutical analysis and related fields. 相似文献