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21.
M. Syazwan Mustaffa M. Hashim R. S. Azis I. Ismail S. Kanagesan M. Misbah Zulkimi 《Journal of Superconductivity and Novel Magnetism》2014,27(6):1451-1462
The microstructure evolution in several polycrystalline Ni0.6Zn0.4Fe2O4 samples as a result of a sintering scheme was studied in detail, in parallel with the changes in their magnetic properties. The Ni0.6Zn0.4Fe2O4 toroidal sample was prepared via mechanical alloying and subsequent molding; the sample with nanometer-sized compacted powder was repeatedly sintered from 600 to 1200 °C with an increment of 25 °C. An integrated analysis of phase, microstructural and hysteresis data pointed to existence of three distinct shape-differentiated groups of B–H hysteresis loops which belong to samples with weak, moderate and strong magnetism (Idza in Mater. Res. Bull. 47:1345–1352, 2012), respectively. The real permeability, μ′, and loss factor, μ″, increased with grain size which increased due to increase in sintering temperature and these two magnetic properties also seem to belong to three value-differentiated groups corresponding to the same temperature ranges found for the B–H groupings. These groupings are tentatively explained using Snoek’s Law. 相似文献
22.
Iwan J. Azis 《The Annals of Regional Science》2000,34(2):251-278
The transition from Asian financial crisis into employment and income loss is analyzed in details by using a structural path analysis (SPA) and a price endogenous model of computable general equilibrium (CGE) type. Indonesia is taken as a case study. It is revealed that the damage in the real sector has ripple effects on the
services sector, reducing the demand for workers of the professional rural and urban category, the growing middle class of
the country. In turn, the overall income of most high urban household declines. The depressed manufacturing and construction
sector gravely injures the companies' financial position. For some sectors, the indirect transmission of the effects is not
insignificant. The large drop of employment in rural professionals suggests that the rural non-farm activities are likely
to receive a recession contagion from the urban-based economy. This also implies that there is no alternative outlet in the
rural areas for the urban middle class who lost their jobs. Very likely, some of them will end up working in the informal
sector. The CGE simulation also suggests that the real wages have declined, especially in the urban areas. The per-capita
consumption of all urban workers drops, the largest decline of which is for the urban medium type. In general, therefore,
the relative position of the urban sector deteriorates more than that in the rural area. Hence, the country has to be prepared
to face a massive increase in urban poverty, a fertile ground for internal conflicts and social discontent.
Received: January 1999/Accepted: April 1999 相似文献
23.
Musa Makiyyu Abdullahi Xu Da Sun Feng Shao Hong Dong Xiangting Azis Raba’ah Syahidah Ugya Adamu Yunusa Ari Hadiza Abdullahi 《Journal of Materials Science: Materials in Electronics》2022,33(5):2375-2385
Journal of Materials Science: Materials in Electronics - Pure zinc ferrite, ZnFe2O4 and aluminum-doped zinc ferrite, Al: ZnFe2O4 (0.5% Al) nanofibers were prepared by the combination of... 相似文献
24.
Chia Chun Loi Huey Chern Boo Abdulkarim Sabo Mohamed Abdul Azis Ariffin 《Journal of the American Oil Chemists' Society》2010,87(6):607-613
Processing of vegetative material containing pentoses has been shown to result in the formation of furfural. Furfural exhibits
a spectrophotometric absorption peak at 518 nm when complexed with aniline acetate. Headspace solid-phase microextraction
(HS-SPME) method has been successfully used to confirm the presence of furfural in crude palm oil (CPO). Solid phase microextraction
(SPME) fiber composed of divinylbenzene/Carboxen/polydimethylsiloxane (DVB/PDMS/CAR) was used to absorb the volatiles in the
headspace of the oil. The isolated compounds from the fiber was desorbed and separated on a capillary polar column of a gas
chromatograph. Response surface methodology (RSM) was used to optimize the SPME fiber condition for maximum absorption of
furfural from CPO. The optimized temperature and time for furfural extraction onto the SPME fiber are 70 °C for 40 min. Oils
obtained from the mill were found to contain between 2 and 13% furfural. 相似文献
25.
M. M. Syazwan M. Hashim R. S. Azis I. Ismail S. Kanagesan A. N. Hapishah 《Journal of Materials Science: Materials in Electronics》2017,28(12):8429-8436
M-type barium ferrite with Mg–Ti substitution and MWCNT addition was synthesized using high-energy ball milling. The prepared sample was further analyzed using X-ray diffraction, field emission scanning electron microscope (FESEM), vibrating sample magnetometer and vector network analyzer. The results showed that the particle size had a wide range of distribution, and a hexagonal structure was formed in the sample. The sample was observed to have lower saturation magnetization and coercivity after Mg–Ti was substituted with MWCNT and added into the barium hexaferrite. Reflection loss was studied as a function of frequency and thickness of the sample. For Mg–Ti substituted barium hexaferrite composite with a thickness of 2.0 mm, the reflection loss peaked at ?28.83 dB at a frequency of 15.57 GHz with a bandwidth of 6.43 GHz at a loss of less than ?10 dB. The microwave absorption primarily resulted from magnetic losses caused by magnetization relaxation, domain wall resonance, and natural resonance. FESEM micrograph demonstrated that carbon nanotubes were attached to the external surface of the ferrite nanoparticles. The investigation of the microwave absorption indicated that with an addition of carbon nanotubes, the real and imaginary parts of permittivity and reflection loss had enhanced to ?34.16 dB at a frequency of 14.19 GHz with a bandwidth of 5.72 GHz. 相似文献
26.
Essential fatty acids of pitaya (dragon fruit) seed oil 总被引:2,自引:0,他引:2
Abdul Azis Ariffin Jamilah BakarChin Ping Tan Russly Abdul RahmanRoselina Karim Chia Chun Loi 《Food chemistry》2009
Hylocereus undatus and Hylocereus polyrhizus are two varieties of the commonly called pitaya fruits. The seeds were separated and the oil was extracted and analysed. Essential fatty acids, namely, linoleic acid and linolenic acid form a significant percentage of the unsaturated fatty acids of the seed oil extract. Both pitaya varieties exhibit two oleic acid isomers. Essential fatty acids are important acids that are necessary substrates in animal metabolism and cannot be synthesised in vivo. Both pitaya varieties contain about 50% essential fatty acids (C18:2 (48%) and C18:3 (1.5%)). This paper details the process of recovering the pitaya seeds and determining the composition of the oil extracted from the seeds. 相似文献
27.
Phenolic compounds in oil palm fruit (E. guineensis) were extracted in soluble free (SFP), insoluble-bound (ISBP) and esterified (EFP) forms. The total phenolic content (TPC) of the oil palm fruit extracts was determined using the Folin–Ciocalteu method and found to range from 5.03 to 9.04 g/L per g of dried weight (DW). The antioxidant activities of oil palm phenolic extracts were analysed using free radical scavenging assays and results showed that oil palm phenolic extracts contained antioxidant activities in the order of ISBP > EFP > SFP. Eight different phenolic acids were identified and quantified using a simple reversed-phase high performance liquid chromatography (HPLC) with a diode array detector (DAD) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). Ferulic, p-hydroxybenzoic and p-coumaric acid were the dominant phenolic acids found in oil palm fruit extracts and ranged from 55 to 376 μg/g of DW. 相似文献
28.
Nur Ain Athirah Apandi Norazila Binti Ibrahim Zuhani Ismail Khan Rabaah Syahidah Azis 《International Journal of Applied Ceramic Technology》2023,20(5):3148-3162
Composite of (1 − x)La0.85Ag0.15MnO3/x graphene (x = 0, 3, and 5 wt.%) and epoxy resin with a ratio of 4:1 were prepared to investigate the influence of the addition of graphene in (1 − x)La0.85Ag0.15MnO3/x graphene on real and imaginary parts of permittivity, permeability, as well as microwave reflection loss (RL), using a vector network analyzer in the 8–18 GHz of the frequency range. It is found that the value of RL is smaller at x = 3 wt.% (−20.74 dB at 14.85 GHz) and 5 wt.% (−14.81 at 16.50 GHz) compared to at x = 0 wt.% (−8.89 dB at 15.90 GHz). The result indicates that microwave absorption properties significantly improved as a result of the addition of graphene. It is suggested that the addition of graphene enhanced the dielectric loss–related mechanism such as interfacial polarization and conduction loss resulting in an improvement of microwave absorption performance for both x = 3 wt.% and x = 5 wt.% samples. It also shows that the observed enhanced microwave absorption properties may also be influenced by the resistivity of the sample as x = 3 wt.% sample exhibits enhanced microwave absorption properties and the lowest resistivity among the studied samples. 相似文献