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41.
Here, we present a method to synthesize expandable spherical polystyrene beads containing well-dispersed water microdroplets. The beads, 2–3 mm in diameter, were prepared through surfactant-free Pickering emulsion polymerization in water-in-oil-in-water (w/o/w) system using cross-linked starch nanoparticles (CSTN) as emulsifier. The CSTNs were in situ surface-modified by styrene maleic anhydride copolymer as confirmed by infrared spectroscopy and contact angle analysis. The entrapped water microdroplets with the average size of 3–4 μm were shown to be surrounded by a dense layer of the CSTN. The number droplet density as well as water encapsulation efficiency in the polystyrene beads increased with the CSTN concentration. Furthermore, regardless of CSTN content, all samples exhibited high encapsulation stability of over 68 % after 3 months. These characteristics along with good expansion behavior suggest the synthesized beads as expandable polystyrene containing water as a green blowing agent. 相似文献
42.
Aslanpanjeh Maryam Poursattar Marjani Ahmad Khalafy Jabbar Etivand Nasser 《Research on Chemical Intermediates》2020,46(1):165-177
Research on Chemical Intermediates - One-pot, three-component reaction of various aryl glyoxal monohydrates, 5-methylisoxazol-3-amine and 4-hydroxyquinolin-2(1H)-one in the presence of a catalytic... 相似文献
43.
Nouri Amrah Marjani Ahmad Poursattar Khalafy Jabbar Etivand Nasser 《Research on Chemical Intermediates》2020,46(6):3025-3036
Research on Chemical Intermediates - New 3-(2-aryl-6-nitro-1H-indol-3-yl)quinoline-2,4(1H,3H)-diones were synthesized, and good-to-excellent yields were achieved through one-pot, three-component... 相似文献
44.
45.
Nasser Metwally 《Physics letters. A》2011,375(48):4268-4273
A theoretical scheme is introduced to generate entangled network via Dzyaloshinskii-Moriya (DM) interaction. The dynamics of entanglement between different nodes, which is generated by direct or indirect interaction, is investigated. It is shown that, the direction of (DM) interaction and the locations of the nodes have a sensational effect on the degree of entanglement. The minimum entanglement generated between all the nodes is quantified. The upper and lower bounds of the entanglement depend on the direction of DM interaction, and the repetition of the behavior depends on the strength of DM. The generated entangled nodes are used as quantum channel to perform quantum teleportation, where it is shown that the fidelity of teleporting unknown information between the network members depends on the locations of the members. 相似文献
46.
47.
Amorphous gallium nitride (a-GaN) thin films were deposited on glass substrate by electron beam evaporation technique at room
temperature and high vacuum using N
2 as carrier gas. The structural properties of the films was studied by X-ray diffraction (XRD) and scanning electron microscope
(SEM). It was clear from XRD spectra and SEM study that the GaN thin films were amorphous. The absorbance, transmittance and
reflectance spectra of these films were measured in the wavelength range of 300–2200 nm. The absorption coefficient spectral
analysis in the sharp absorption region revealed a direct band gap of E
g = 3:1 eV. The data analysis allowed the determination of the dispersive optical parameters by calculating the refractive
index. The oscillator energy E
0 and the dispersion energy E
d, which is a measure of the average strength of inter-band optical transition or the oscillator strength, were determined.
Electrical conductivity of a-GaN was measured in a different range of temperatures. Then, activation energy of a-GaN thin
films was calculated which equalled E
a = 0:434 eV. 相似文献
48.
A new, mild, and novel method is described for the efficient deoxygenation of sulfoxides to their corresponding sulfides with 1,3-dithiane at room temperature in the presence of catalytic amounts of N-bromosuccinimide (NBS), 2,4,4,6-tetrabromo-2,5-cyclohexadienone (TABCO), or Br(2) as the source of electrophilic bromine. 相似文献
49.
M.A. Nasser M.M. Gazzaly J.V. Geaga B. Höistad G. Igo J.B. McClelland A.L. Sagle H. Spinka J.B. Carroll V. Perez-Mendez E.T.B. Whipple 《Nuclear Physics A》1978,312(3):209-216
The p-4He elastic differential cross section has been measured at a kinetic energy of 2.68 GeV. The momentum transfer region studied is t = 0.15–0.66 (GeV/c)2. The cross section displays a shallow first minimum and shape very similar to recent data at 1 GeV. 相似文献
50.
We analyze in detail an almost optimal algorithm for generating an exponentially distributed variate. The algorithm is due to Knuth and Yao and relies on a method which goes back to J. von Neumann. It is shown here that it can generate k bits of an exponentially distributed variate using an average of about k + 5.67974692 coin flippings. This solves a problem left open by Knuth and Yao. 相似文献