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971.
Tai Y Sharma J Chang HC Tien TV Chiou YS 《Chemical communications (Cambridge, England)》2011,47(6):1785-1787
In this communication, we demonstrate the inter-conversion of crystal structure of aluminium doped zinc oxide (AZO) thin films from highly (002) plane oriented vertical growth to (103) plane oriented lateral growth by adjusting the polarity of the self-assembled monolayers (SAMs) on glass substrates at room temperature. 相似文献
972.
973.
Thi Kim Ngan Nguyen 《Comptes Rendus Mathematique》2011,349(5-6):233-237
In this Note, we establish a general formula for the unramified cohomology of fields of linear invariants by finite groups. Such formulas are known in degree 2 and 3. 相似文献
974.
Yen‐Thi‐Hai Quach Laurent Ferry Rodolphe Sonnier José‐Marie Lopez Cuesta 《先进技术聚合物》2013,24(1):104-113
The thermal and fire properties of polystyrene (PS) flame retarded by a system composed of ammonium polyphosphate (APP) and wollastonite (W) were investigated by thermogravimetric analysis, pyrolysis‐combustion flow calorimeter, pyrolysis gas chromatography mass spectrometry, cone calorimetry and epiradiator. The combustion residues were observed by scanning electron microscopy/energy dispersive X‐ray spectroscopy and analyzed by X‐ray diffraction. The combination of both additives enables increasing the thermal stability of PS while increasing simultaneously the high temperature residue. The peak of HRR was also significantly reduced while time to ignition varied depending on the composition. It was shown that the degradation pathway of PS was affected by the presence of the additives implying a reduction of the effective heat of combustion. In the condensed phase, APP decomposition promotes char formation and favors the reactivity between phosphorus and silicate. A layer composed of char, W and a mixture of calcium and silicon phosphate is formed at the sample surface during combustion. This layer is cohesive enough to limit the release of combustible gases to the gas phase. Moreover, the thermally stable protective layer reaches high temperature enabling the re‐irradiation of a part of the incident heat flux. The flame retardancy of PS is thus enhanced. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
975.
Duc Minh Truong Hoai Thi Xuan Nguyen An Ba Nguyen 《International Journal of Theoretical Physics》2014,53(3):899-910
In this paper, we study some higher-order nonclassical properties and intermodal entanglement that may arise in the so called two-mode photon-added displaced squeezed state. We derive analytical expressions for the degree of sum squeezing and difference squeezing, which are interesting kinds of two-mode squeezing, as well as for the degree of antibunching to any orders. We also examine the degree of entanglement between the two modes using the existing Hillery-Zubairy criterion. Based on the derived expressions we analyze in detail the behavior of these nonclassical effects and entanglement depending on the parameters involved. 相似文献
976.
Hong Ha Thi Vu Timur Sh. Atabaev Nang Dinh Nguyen Yoon-Hwae Hwang Hyung-Kook Kim 《Journal of Sol-Gel Science and Technology》2014,71(3):391-395
Bifunctional magneto-optical nanocomposites with Fe3O4 nanoparticles as a core and erbium and lithium codoped gadolinium (Gd2O3:Er3+, Li+) as the shell were synthesized successfully using a simple urea homogeneous precipitation method. The fabricated Fe3O4@Gd2O3:Er3+, Li+ particles were characterized by X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, photoluminescence spectroscopy and quantum design vibrating sample magnetometry. The upconversion emission intensity was enhanced significantly comparing to that without Li+ ions. These bifunctional composites are expected to be potentially applied for drug delivery, cell separation and bioimaging. 相似文献
977.
LTMP (5 equiv) metalates randomly veratric acid (1). Under external quench conditions, the thermodynamically more stable lithium 2-lithio-3,4-dimethoxybenzoate (2) reacts with a variety of electrophiles to give versatile building units that are not easily accessible by conventional means. Under in situ quench conditions (LTMP/TMSCl), a reversal of regioselectivity is observed and 6-trimethylsilyl-3,4-dimethoxybenzoic acid (10) is formed predominantly. 相似文献
978.
Identifying significant variations in genomes can be cumbersome, as the variations span a multitude of base pairs and can make genome assembly difficult. However, large DNA molecules that span the variation aid in assembly. Due to the DNA molecule's large size, routine molecular biology techniques can break DNA. Therefore, a method is required to concentrate large DNA. A bis-acrylamide roadblock was cured in a proof-of-principle 3D printed device to concentrate DNA at the interface between the roadblock and solution. Lambda concatemer DNA was stained with YOYO-1 and loaded into the 3D printed device. A dynamic range of voltages and acrylamide concentrations were tested to determine how much DNA was concentrated and recovered. The fluorescence of the original solution and the concentrated solution was measured, the recovery was 37% of the original sample, and the volume decreased by a factor of 3 of the original volume. 相似文献
979.
The paper investigates DC programming and DCA for both modeling discrete portfolio optimization under concave transaction costs as DC programs, and their solution. DC reformulations are established by using penalty techniques in DC programming. A suitable global optimization branch and bound technique is also developed where a DC relaxation technique is used for lower bounding. Numerical simulations are reported that show the efficiency of DCA and the globality of its computed solutions, compared to standard algorithms for nonconvex nonlinear integer programs. 相似文献
980.
In this paper, we are interested in the survivable network design problem (SNDP) for last mile communication networks called (L-SNDP). Given a connected, weighted, undirected graph \(\mathrm{{G}} = (\mathrm{V, E})\); a set of infrastructure nodes and a set of customers C including two customer types where customers in the subset C1 require a single connection (type-1) and customers in the subset C2 need to be redundantly connected (type-2). The aim is to seek a sub-graph of G with the smallest weight in which all customers are connected to infrastructure nodes and the connections are protected against failures. This is a NP-hard problem and it has been solved only with the objective of minimizing the network cost. In this paper, we introduce a new multi-objective approach to solve L-SNDP called ML-SNDP. These objectives are to minimize the network cost (total cost) and to minimize the maximal amount of sharing links between connections. Results of computational experiments reported show the efficiency of our proposal. 相似文献