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101.
102.
A right module $M$ over an associative ring $R$ with unity is a $QTAG$-module if every finitely generated submodule of any homomorphic image of $M$ is a direct sum of uniserial modules. This article considers the closure of $h$-pure-$S$-high submodules of $QTAG$-modules. Here, we determine all submodules $S$ of a $QTAG$-module $M$ such that each closure of $h$-pure-$S$-high submodule of $M$ is $h$-pure-$\overline{S}$-high in $\overline{M}$. A few results of this theme give a comparison of some elementary properties of $h$-pure-$S$-high and $S$-high submodules. 相似文献
103.
Passively Q-Switched EDFL Using a Multi-Walled Carbon Nanotube Polymer Composite Based on a Saturable Absorber 下载免费PDF全文
A stable passive Q-switched erbium-doped fiber laser (EDFL) operating at 1563.5 nm is demonstrated by using a multi-walled carbon nanotube (MWCNT) polymer composite film based saturable absorber for the first time. The composite is prepared by mixing the MWCNTs homogeneous solution into a dilute PEO polymer solution before it is left to dry at room temperature to produce thin film. Then the film is sandwiched between two FC/PC fiber connectors and is integrated into the laser cavity for Q-switching pulse generation. The EDFL generates a stable pulse train with repetition rates ranging from 4.5 kHz to 20.0 kHz by varying the 1480 nm pump power from 35 mW to 53 mW. At the 53 mW pump power, the pulse width and pulse energy are 8.8 μs and 15.3 nJ, respectively. 相似文献
104.
Electrical field analysis of metal‐surface plasmon resonance using a biaxially strained Si substrate
Daisuke Kosemura Siti Norhidayah binti Che Mohd Yusoff Atsushi Ogura 《Journal of Raman spectroscopy : JRS》2014,45(6):414-417
Electrical field components of metal‐surface plasmon resonance were analyzed in detail. Both longitudinal optical (LO) and transverse optical (TO) phonon modes of a biaxially strained Si layer can be excited by surface‐enhanced Raman spectroscopy (SERS). The z to y polarization ratio in SERS measurements was calculated to be 0.78 using the intensity ratio of TO to LO phonon modes. The electrical field components of SERS were also calculated by the finite‐difference time‐domain method. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
105.
Growth of Fe-doped ZnO nanorods using aerosol-assisted chemical vapour deposition via in situ doping
Siti Nor Qurratu Aini Abd Aziz Swee-Yong Pung Zainovia Lockman 《Applied Physics A: Materials Science & Processing》2014,116(4):1801-1811
In situ Fe doping of ZnO nanorods (NRs) was performed using aerosol assisted chemical vapour deposition (AA-CVD) technique. As the aerosol generator is located outside the reactor, AA-CVD provides the flexibility to control doping parameters, such as doping timing, doping duration and a wider choice of dopant precursors. The Fe dopant aerosol was flowed into the reactor during the growth of ZnO NRs to achieve in situ doping. The X-ray diffraction analysis indicates that the Fe dopants were introduced into the ZnO lattice and present mainly in the form of Fe2+. This result is supported by the X-ray photoelectron spectroscopy analysis as the doublet separation is 13.6 eV, although there is a shift of Fe1/2 and Fe3/2 peaks to a lower binding energy levels. A strong green emission of PL of Fe-doped ZnO NRs shows that the NRs have poor crystal quality attributed to the Fe-induced defects (recombination centres). The poor photocatalytic performance in degrading Rhodamine B solution of Fe-doped ZnO NRs further proves that the Fe-induced defects were recombination centres rather than traps. Lastly, the growth mechanism of in situ Fe doping of ZnO NRs was discussed. 相似文献
106.
Dileep Kumar Malik Abdul Rub Mohd. Akram Kabir‐ud‐Din 《Journal of Physical Organic Chemistry》2014,27(9):729-734
In the present paper, reaction of zinc‐glycylphenylalanine ([Zn(II)‐Gly‐Phe]+) with ninhydrin has been investigated in gemini (m‐s‐m type; m = 16, s = 4–6) surfactants at temperature (70 °C) and pH (5.0). Monitoring the appearance of product at 400 nm was used to follow the kinetics, spectrophotometrically. The order of the reaction with respect to [Zn(II)‐Gly‐Phe]+ was unity while with respect to [ninhydrin] was fractional. The reaction constants involved in the mechanism were obtained. In addition to the rate constant (kΨ) increase and leveling‐off regions are observed with the geminis, just like as seen with conventional surfactant hexadecyltrimethylammonium bromide (CTAB), the former produced a third region of increasing kΨ at higher concentrations. A close agreement between observed and calculated rate constants was found under varying experimental conditions. A suitable mechanism consistent with the experimental findings has been proposed. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
107.
W. L. Tham Z. A. Mohd Ishak W. S. Chow 《Journal of Macromolecular Science: Physics》2014,53(3):371-382
Poly(lactic acid) (PLA)/halloysite composites were prepared using melt compounding followed by compression molding. Maleic anhydride grafted styrene-ethylene/butylene-styrene (SEBS-g-MAH) was used to toughen the PLA composites. The mechanical properties of the PLA composites were studied through tensile, flexural, and impact tests. The thermal properties were characterized by using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The fracture surfaces of the composites were assessed by using field emission scanning electron microscopy (FESEM). The impact strength and thermal properties of the PLA/halloysite composites were increased by addition of SEBS-g-MAH. 相似文献
108.
In the present work, Vickers microhardness measurements were carried out on different faces i.e. (1 0 0), (0 0 1) and (1 0 1) of ammonium dihydrogen phosphate (ADP) single crystals grown by slow evaporation solution technique at room temperature in the load ranging from 0.2 to 2 N. The obtained results show that the load independent hardness values are 0.8, 0.7 and 0.66 GPa, respectively at different faces of ADP crystal. From the crack length measurements, the fracture toughness values (Kc) was estimated using Evans and Anstis model and the present studies suggest that Evans model is more relevant when compared to Anstis model. The load variation of some mechanical properties viz. brittle index number (Bi) and yield strength (σy) for ADP have also been calculated for the first time. 相似文献
109.
Subhash Bhatia Noor Asmawati binti Mohd Zabidi Megat Harun Al Rashid bin Megat Ahmad 《Reaction Kinetics and Catalysis Letters》2001,74(1):87-92
The catalytic activity of Ni/MgO catalysts was studied for the oxidative coupling of methane (OCM). The catalysts were characterized
using transmission electron microscope (TEM) and XRD. The increase in C2+ selectivity of Ni/MgO was attributed to the presence
of bulk dislocations and MgNiO2 phase.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
110.
The topological Tverberg theorem has been generalized in several directions by setting extra restrictions on the Tverberg partitions. Restricted Tverberg partitions, defined by the idea that certain points cannot be in the same part, are encoded with graphs. When two points are adjacent in the graph, they are not in the same part. If the restrictions are too harsh, then the topological Tverberg theorem fails. The colored Tverberg theorem corresponds to graphs constructed as disjoint unions of small complete graphs. Hell studied the case of paths and cycles. In graph theory these partitions are usually viewed as graph colorings. As explored by Aharoni, Haxell, Meshulam and others there are fundamental connections between several notions of graph colorings and topological combinatorics. For ordinary graph colorings it is enough to require that the number of colors q satisfy q>Δ, where Δ is the maximal degree of the graph. It was proven by the first author using equivariant topology that if q>Δ 2 then the topological Tverberg theorem still works. It is conjectured that q>KΔ is also enough for some constant K, and in this paper we prove a fixed-parameter version of that conjecture. The required topological connectivity results are proven with shellability, which also strengthens some previous partial results where the topological connectivity was proven with the nerve lemma. 相似文献