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101.
102.
We discuss the entanglement phenomenon on the example of the Smolin state of four qubits. This state is known as the bound entangled state and its spin tomogram is found in an explicit form. We apply the qubit-portrait method for investigating the violation of the Bell inequalities, since this approach provides another tool to prove the entanglement properties of the four-qubit state under consideration. 相似文献
103.
Formation of homogeneous nanocomposite films at ambient temperature via miniemulsion polymerization using graphene oxide as surfactant 下载免费PDF全文
Yasemin Fadil S. H. C. Man Florent Jasinski Hideto Minami Stuart C. Thickett Per B. Zetterlund 《Journal of polymer science. Part A, Polymer chemistry》2017,55(14):2289-2297
A convenient and industrially scalable method for synthesis of homogeneous nanocomposite films comprising poly(styrene‐stat‐butyl acrylate) and nanodimensional graphene oxide (GO) or reduced GO (rGO) is presented. Importantly, the nanocomposite latex undergoes film formation at ambient temperature, thus alleviating any need for high temperature or high pressure methods such as compression molding. The method entails synthesis of an aqueous nanocomposite latex via miniemulsion copolymerization relying on nanodimensional GO sheets as sole surfactant, followed by ambient temperature film formation resulting in homogeneous film. For comparison, a similar latex obtained by physical mixing of a polymer latex with an aqueous GO dispersion results in severe phase separation, illustrating that the miniemulsion approach using GO as surfactant is key to obtaining homogeneous nanocomposite films. Finally, it is demonstrated that the GO sheets can be readily reduced to rGO in situ by heat treatment of the film. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2289–2297 相似文献
104.
Kinetics and Mechanism of the Reaction of a Ruthenium(VI) Nitrido Complex with HSO3− and SO32− in Aqueous Solution 下载免费PDF全文
Dr. Qian Wang Hong Yan Zhao Dr. Wai‐Lun Man Dr. William W. Y. Lam Dr. Kai‐Chung Lau Prof. Tai‐Chu Lau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(31):10754-10758
The kinetics and mechanism of the reaction of SIV (SO32?+HSO3?) with a ruthenium(VI) nitrido complex, [(L)RuVI(N)(OH2)]+ (RuVIN, L=N,N′‐bis(salicylidene)‐o‐cyclohexyldiamine dianion), in aqueous acidic solutions are reported. The kinetic results are consistent with parallel pathways involving oxidation of HSO3? and SO32? by RuVIN. A deuterium isotope effect of 4.7 is observed in the HSO3? pathway. Based on experimental results and DFT calculations the proposed mechanism involves concerted N?S bond formation (partial N‐atom transfer) between RuVIN and HSO3? and H+ transfer from HSO3? to a H2O molecule. 相似文献
105.
Polypropylene-block-poly(vinylpyrrolidone) copolymer was synthesized through the esterification of dicarboxyl-terminated polypropylene with monohydroxyl-terminated poly(vinylpyrrolidone) and used as a macromolecular surface modifier to improve the surface hydrophilicity of PP. The results of ATR-FTIR and contact angles measurements indicated that PP-b-PVP could diffuse preferably onto the surface by the inducement of high energy interface and lower the water contact angle of polypropylene. Lower loading and lower molecular weight of PP and PVP segment would result in higher surface selective enrichment. 相似文献
106.
The design variable tolerance effects on the natural frequency variance of constrained multi-body systems in dynamic equilibrium are investigated in this study. Monte-Carlo simulation is often employed for such investigations, but it is known to have serious drawbacks. Excessive amount of computation time needs to be consumed since a large number of evaluations are usually required for the method. Furthermore, the solution accuracy cannot be always guaranteed in spite of the excessive amount of computation time. In order to overcome such drawbacks, a method employing eigenvalue sensitivity information is proposed to obtain the variance of natural frequency in this study. In order to verify the accuracy and the efficiency of the method, some numerical examples of multi-body systems in dynamic equilibrium are solved and the results are compared to those obtained by an analytical method and Monte-Carlo simulation. 相似文献
107.
Using two-colour visible (Vis)–ultraviolet (UV) photoionisation and pulsed field ionisation–photoelectron (PFI–PE) methods, we have obtained cleanly rotationally resolved photoelectron spectra for ZrO+(X 2Δ3/2,5/2; v+ = 0, 1, and 2). The rotation assignment of these state-to-state Vis–UV–PFI–PE spectra has allowed the unambiguous determination of the ground state term symmetry for ZrO+(X) to be 2Δ3/2, and the adiabatic ionisation energy of 90Zr16O, IE(90Zr16O) = 54,948.3(8) cm?1 [6.81272(10) eV]. The symmetry of the ionic ZrO+(X 2Δ3/2) ground state determined here disagrees with that reported in previous experiments. The rotational and vibrational constants determined in this experiment for the ionic 90Zr16O+(X 2Δ3/2) ground state are: Be+ = 0.4343(8) cm?1 and αe+ = 0.0019(5) cm?1, and ωe+ = 991.2(8) cm?1 and ωe+xe+ = 3.5(8) cm?1; and those for the ionic 90Zr16O+(X 2Δ5/2) excited spin-orbit state are: Be+ = 0.4357(6) cm?1 and αe+ = 0.0022(4) cm?1, and ωe+ = 991.9(8) cm?1 and ωe+xe+ = 3.6(8) cm?1, respectively. Based on the latter Be+ value, the equilibrium bond distances are determined to be re+ = 1.691(2) Å for 90Zr16O+(X 2Δ3/2) and re+ = 1.688(1) Å for 90Zr16O+(X 2Δ5/2). The IE(ZrO) along with the spectroscopic constants obtained here are valuable for benchmarking the ab initio quantum chemical calculations for energetic and structural predictions of ZrO/ZrO+. 相似文献
108.
A bifunctional benzoxazine monomer, 6,6′‐bis(3‐allyl‐3,4‐dihydro‐2H‐benzo[e][1,3]oxazinyl) sulfone (BS‐ala), was synthesized from bisphenol‐S, allylamine and formaldehyde via a solution method. The chemical structure of BS‐ala was confirmed by 1H and 13C nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, and elemental analysis. The polymerization behavior of BS‐ala was investigated by FTIR, solid‐state 13C NMR, and differential scanning calorimetry (DSC). The oxazine ring opening polymerization is prior to the addition polymerization of allyl group, and the exothermic peaks corresponding to the two reactions appear partially overlapped in the DSC curve. The storage modulus of the resultant polybenzoxazine at 25°C is about 3.9 GPa, and the glass transition temperature is 254°C. The 5% and 10% weight loss temperatures of the polybenzoxazine are about 335°C and 361°C in both air and nitrogen, respectively. The char yield is about 58% at 800°C in nitrogen, whereas almost no residue is remained at 700°C in air. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
109.
Microwave (MW) radiation has been used in chemical analysis and chemical synthesis. MW heating under controlled conditions offers distinct advantages over conventional heating. The reactions are carried out in environmentally clean and safe solvents and in many cases, reactions can be carried out under solvent‐free conditions. This method of synthesis has grown rapidly and found its use in various sectors. This paper reviews some of the reactions that have been accelerated with higher yields under MW irradiation. The application of MW‐assisted synthesis in the medicinal and pharmaceutical industries will be emphasized. 相似文献
110.
The heparin-loaded microcapsules were successfully prepared by layer-by-layer deposition of chitosan (CHI) and heparin (Hep). Film growth was confirmed by the reversal of ζ-potentials during polysaccharide deposition. Both scanning electron microscopy and transmission electron microscope evidenced the integrity of (CHI/Hep)5 capsules after the removal of cores. By assembling the carriers with chitosan that are inherently degradable, the capsules were engineered to degrade specifically in the presence of lysozyme. It was demonstrated that the loaded heparin was released from the capsules over a long period of time when being incubated in lysozyme solution. With these results, such CHI/Hep capsules may have a great potential as controlled release carrier for heparin. 相似文献