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91.
Mohd Zobir bin Hussein Mohammad Yeganeh Ghotbi Asmah Hj Yahaya Mohd Zaki Abd Rahman 《Solid State Sciences》2009,11(2):368-375
Zinc hydroxide nitrate, a brucite-like layered material was synthesized using pH control method. Poly(vinyl alcohol) and poly(ethylene glycol) were used at various percentages as size decreasing agents during the synthesis of zinc hydroxide nitrate. SEM and PXRD showed the decrease of size and thickness of the resultant zinc hydroxide nitrates. TG and surface area data confirmed the decrease of the particle sizes, too. When zinc hydroxide nitrates were heat treated at 500 °C, the physical properties of nano zinc oxides obtained depended on the parent material, zinc hydroxide nitrate. 相似文献
92.
Hj. Wacker 《Mathematical Methods of Operations Research》1988,32(2):94-94
Communicated by Professor Zimmermann 相似文献
93.
Dipl.-Ing. W. Bauer Dipl.-Ing. Dr. H. Gfrerer Prof. Dr. Hj. Wacker 《Mathematical Methods of Operations Research》1984,28(4):B103-B131
This paper is concerned with the optimization of base load production of hydro energy storage plants within a given time interval at a varying tariff rate. For three real world storage plants in Austria, each of them presenting some characteristic difficulty we discuss both mathematical models and numerical techniques. Beside classical techniques as Dynamic Programming and Simulation two newly developed nonlinear optimization methods were used.The first combines the Homotopy method with the active index set strategy, the second technique is based on decomposition and is strongly directed to the special structure of the problems.This paper was partially supported by the Fonds zur Förderung der österreichsichen Forschung (Nr. 3472 and Nr. 4786) 相似文献
94.
Intan Safinar Ismail Yuta Nagakura Takahiro Hosoya Nordin Hj Lajis 《Tetrahedron letters》2009,50(34):4830-1185
Two novel triterpenes, acutaxylines A (1) and B (2) consisting of a cyclopentenone side chain at C-17 and an oxepan-2-ol, were isolated from the leaves of Dysoxylum acutangulum. The relative stereochemistry of 1 and 2 was determined by NOESY correlations. Acutaxyline B showed moderate cytotoxicity against human blood premyelocytic leukemia cells. 相似文献
95.
Mohammad Yeganeh Ghotbi Mohd Zobir bin Hussein Asmah Hj Yahaya Mohd Zaki Abd Rahman 《Solid State Sciences》2009,11(12):2125-2132
A series of brucite-like materials, undoped and doped zinc layered hydroxide nitrate with 2% (molar) Fe3+, Co2+ and Ni2+ were synthesized. Organic–inorganic nanohybrid material with gallate anion as a guest, and zinc hydroxide nitrate, as an inorganic layered host was prepared by the ion-exchange method. The nanohybrid materials were heat-treated at various temperatures, 400–700 °C. X-ray diffraction, thermal analysis and also Fourier transform infrared results showed that incorporation of the doping agents within the zinc layered hydroxide salt layers has enhanced the heat-resistivity of the nanohybrid materials in the thermal decomposition pathway. Porous carbon materials can be obtained from the heat-treating the nanohybrids at 600 and 700 °C. Calcination of the nanohybrids at 700 °C under nitrogen atmosphere produces mesoporous and high pore volume carbon materials. 相似文献
96.
Magnetic and microwave absorbing properties of magnetite-thermoplastic natural rubber nanocomposites 总被引:1,自引:0,他引:1
Ing Kong Sahrim Hj Ahmad David Hui Dwi Puryanti 《Journal of magnetism and magnetic materials》2010,322(21):3401-3409
Magnetic and microwave absorbing properties of thermoplastic natural rubber (TPNR) filled magnetite (Fe3O4) nanocomposites were investigated. The TPNR matrix was prepared from polypropylene (PP), natural rubber (NR) and liquid natural rubber (LNR) in the ratio of 70:20:10 with the LNR as the compatibilizer. TPNR-Fe3O4 nanocomposites with 4-12 wt% Fe3O4 as filler were prepared via a Thermo Haake internal mixer using a melt-blending method. XRD reveals the presence of cubic spinel structure of Fe3O4 with the lattice parameter of a=8.395 Å. TEM micrograph shows that the Fe3O4 nanoparticles are almost spherical with the size ranging 20-50 nm. The values of saturation magnetization (MS), remanence (MR), initial magnetic susceptibility (χi) and initial permeability (μi) increase, while the coercivity (HC) decreases with increasing filler content for all compositions. For nanocomposites, the values of the real (εr′) and imaginary permittivity (εr′′) and imaginary permeability (μr′′) increase, while the value of real permeability (μr′) decreases as the filler content increases. The absorption or minimum reflection loss (RL) continuously increases and the dip shifts to a lower frequency region with the increasing of both filler content in nanocomposites and the sample thickness. The RL is −25.51 dB at 12.65 GHz and the absorbing bandwidth in which the RL is less than −10 dB is 2.7 GHz when the filler content is 12 wt% at 9 mm sample thickness. 相似文献
97.
Westerholt K Sprungmann D Zabel H Brucas R Hjörvarsson B Tikhonov DA Garifullin IA 《Physical review letters》2005,95(9):097003
We studied superconducting V layers deposited on an antiferromagnetically coupled [Fe(2)V(11)](20) superlattice. The parallel upper critical magnetic field exhibits an anomalous T dependence up to the ferromagnetic saturation field of the superlattice, indicating that the superconducting transition temperature T(S) decreases when rotating the relative sublattice magnetization directions of the superlattice from antiparallel to parallel. This proves that the pair breaking effect of a Fe2 layer is reduced if at a distance of 1.5 nm a second Fe2 layer with antiparallel spin orientation exists. 相似文献
98.
Kin Hong Liew Wan Zurina Samad Norazzizi Nordin Poh Lee Loh Joon Ching Juan Mohd Ambar Yarmo Badrul Hisham Yahaya Rahimi M. Yusop 《催化学报》2015,(5)
A new heterogeneous catalyst composed of Pd nanoparticles immobilized within a HypoGel resin has been prepared in the absence of any ligands using an extensive cross-linking method. This new-ly develop... 相似文献
99.
100.
Nurshazliana Othman Vuanghao Lim Muggundha Raoov Ramachandran Mohd Marsin Sanagi Sazlinda Kamaruzaman Yuichiro Hirota Norikazu Nishiyama Noorfatimah Yahaya 《Chromatographia》2017,80(10):1553-1562
A rapid, simple, and efficient method using ultrasound-assisted emulsification microextraction combined with dispersive micro-solid phase extraction (USAE-D-µ-SPE) was developed for detection and quantification of three azole antifungals in milk samples by high-performance liquid chromatography diode array detector. In this study, mesoporous carbon, COU-2, was used as sorbent in USAE-D-µ-SPE for the extraction and preconcentration of analytes. Several important experimental parameters, including type of deproteinized solvents, desorption time, type of extraction solvents, volume of extraction solvent, extraction time, emulsification time, sample pH, salt addition, and mass of COU-2 sorbent, were optimized using spiked milk samples. Under the optimum extraction and detection conditions, three azole antifungals, namely ketoconazole, clotrimazole, and miconazole, were determined within 20 min, with good linearity of matrix-matched calibration in the range of 0.5–5000.0 µg L?1 with coefficient of determination, r 2 ≥ 0.9943. The method showed limits of detection and limits of quantification of all analytes in the range of 0.15–3.0 and 0.5–10.0 µg L?1, respectively. Good repeatability with RSDs <15% (n = 3) and satisfactory relative recoveries (83.3–111.1%) were obtained for spiked azole antifungal drugs in milk. The results reveal that the developed USAE-D-µ-SPE method was a simple, rapid, efficient, environmentally friendly, and practicable method for the determination of azole antifungals in milk samples. 相似文献