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51.
Rare earth and transition metal doped (NdFeCo) thin films were fabricated on Si (100) substrate by pulsed laser deposition technique keeping the substrate at constant temperature of 300 °C. A KrF Excimer laser (248 nm, 20 ns) was used as an energy source for the deposition. Thin films were deposited without and under the influence of transverse magnetic field applied across the plume. The applied magnetic field was varied from 3 to 6 kOe. The deposited films were characterized by XRD, FESEM, VSM and SE (Spectroscopic Ellipsometry). The deposited films were amorphous in nature. All the films regardless of the applied magnetic field exhibit perpendicular magnetic anisotropy. The thickness of the thin films was found to increase monotonically from 166 to 266 nm with the increase in the applied external magnetic field. The saturation magnetization has a maximum value of 1682 emu/cc for the film deposited under 4.5 kOe magnetic field. The value of optical band gap energy for the same film is found to have a maximum value of 3.1 eV. The values of both the saturation magnetization and the band gap energy were decreased with the increase in the applied magnetic field. 相似文献
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Faqir M Anjum George L Lookhart Charles E Walker 《Journal of the science of food and agriculture》2000,80(2):219-225
Eleven Pakistani hard white spring wheat cultivars, along with one durum wheat and two hard white American‐grown wheat cultivars, were evaluated for their high‐molecular‐weight (HMW) glutenin subunit composition via sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS‐PAGE). The relationships among different quality characteristics and between these characteristics and HMW glutenin subunits were computed. Three to six HMW glutenin subunits were observed in Pakistani bread wheat cultivars. The presence of HMW glutenin subunits was not affected by growth locations or crop years. However, variations in intensities were observed. Correlations were noticed between certain HMW glutenin subunits and some quality attributes, such as protein, farinograph dough development time, farinograph water absorption, loaf volume and mixograph peak height. The presence of HMW glutenin subunit 20 in the older wheat cultivars C591 and C273, known for excellent chapati quality, indicated a possible relationship between this band and chapati quality. This observation will need to be confirmed by testing a larger number of wheat samples known to have characteristics for both good and poor chapati quality. © 2000 Society of Chemical Industry 相似文献
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Sidra Nisar Ahmed Mushtaq Ahmad Ghulam Yaseen Muhammad Zafar Sofia Rashid Abdul Nazir Shazia Sultana Farida Anjum Fethi Ahmet Ozdemir Omer Kilic 《Microscopy research and technique》2021,84(1):28-37
The quality assurance and authentication of crude herbal drugs play important role in the effective therapeutic effect of herbal drug and their products. There are many reported problems in quality assurance of herbal crude drugs concerning to their correct identification. The present study was designed with the aim to document the authentication and quality assurance of the herbal crude drugs (Argyrolobium roseum and Viola stocksii) thorough light microscopy (LM) and scanning electron microscopy (SEM). The detailed foliar anatomical studies showed polygonal epidermal cells having anticlinal walls in Argyrolobium roseum while rounded epidermal cells were observed in Viola stocksii. The anomocytic stomata type was observed in Argrolobium roseum while actinocytic was noticed in Viola stocksii. The pollen of studied species appeared as tricolporate showing reticulate exine sculpturing in Argrolobium roseum while fine perforations were recorded in Viola stocksii. Furthermore, quantitative analysis of phenols, flavonoids, and antioxidant activity showed high flavonoid and phenol content in Argyrolobium roseum as compared with Viola stocksii. It was observed that Argyrolobium roseum was discriminated from the Viola stocksii based on the leaf and pollen micromorphological traits by using LM and SEM techniques. It was concluded that LM and SEM techniques were found useful for the quality assurance of botanicals and their authentication. 相似文献
56.
Ishtiaque Ahmad Anjum Khalique Muhammad Junaid Muhammad Qamar Shahid Muhammad Imran Abdul Ahid Rashid 《International Journal of Food Science & Technology》2020,55(6):2580-2588
The objective of this study was to evaluate the effect of apple peel polyphenol extract (APPE) on the microbiological and physicochemical properties of yoghurt ice cream stored at −20 °C for 90 days. Five level of APPE were added in yoghurt ice cream as: CTL (control without APPE); AE1 (1% APPE); AE2 (2% APPE); AE3 (3% APPE); AE4 (4% APPE); and AE5 (5% APPE). Samples with APPE had viable counts of Lactobacillus acidophilus and Bifidobacterium lactis of ≥8 log cfu g−1 and >7 log cfu g−1, respectively, during 90 days storage except the control sample. The highest viability of probiotics was obtained in the sample fortified with 5% APPE. The presence of APPE increased the acidity, decreased the melting rate and enhanced the overrun. Compared with the control sample, the hardness of the experimental samples increased with the fortification of APPE. The addition of APPE significantly increased sensory attributes. 相似文献
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Thin films of polymethyl methacrylate (PMMA) were synthesized. Ferric oxalate was dispersed in PMMA films. These films were irradiated with 80 MeV O6+ ions at a fluence of 1×1011 ions/cm2. The radiation induced changes in electrical conductivity, Mössbauer parameter, microhardness and surface roughness were investigated. It is observed that hardness and electrical conductivity of the film increases with the concentration of dispersed ferric oxalate and also with the fluence. It indicates that ion beam irradiation promotes (i) the metal to polymer bonding and (ii) convert the polymeric structure into hydrogen depleted carbon network. Thus irradiation makes the polymer harder and more conductive. Before irradiation, no Mössbauer absorption was observed. The irradiated sample showed Mössbauer absorption, which seems to indicate that there is significant interaction between the metalion and polymer matrix. Atomic force microscopy shows that the average roughness (R a) of the irradiated film is lower than the unirradiated one. 相似文献
58.
Sarzamin Khan Sheraz Anjum Usman Ali Gulzari Farruh Ishmanov Maurizio Palesi Muhammad Khalil Afzal 《Applied Intelligence》2018,48(12):4792-4804
In this paper, we propose an optimized, search based near-optimal mapping heuristic, named as ONMAP for mapping real time embedded application workloads on 2D based on-chip interconnection network platforms. ONMAP exploits NMAP, a well-known and fast nearest neighbor heuristic algorithm by using the modular exact optimization method. The proposed hybrid algorithm minimizes the on-chip inter-processor communication energy consumption and optimizes the interconnection network performance parameters. The algorithm inherits the constructive search based heuristic nature of the NMAP algorithm, as well as the property of exact optimization for mapping embedded applications on the target communication architecture. To verify the efficiency and effectiveness of the algorithm, we have compared the proposed algorithm with NMAP and random mapping algorithm under similar simulation environments and traffic conditions. The mapping results of the exemplary real world applications such as VOPD, PIP, MPEG4, MWD, MMS and WiFi-80211arx indicate that ONMAP algorithm is more efficient than its competitors for most of the performance parameters of the on-chip network designs. The algorithm successfully optimized the energy consumption, up to 20 % and 26% in comparison to NMAP and random algorithms, respectively. Similarly, the cost is optimized up to 10% and 60% as compared to NMAP and random mapping algorithms, respectively. 相似文献
59.
Safia Anjum Hafsa Saleem Khalid Rasheed Rehana Zia Saira Riaz Arslan Usman 《Journal of Superconductivity and Novel Magnetism》2017,30(5):1177-1186
In the present work, nickel-doped iron oxide (NixFe3?x O 4) nanoparticles with different concentration of nickel (x = 0, 0.05, 0.1, and 0.15) have been prepared by co-precipitation method. These prepared nanoparticles have been characterized by using x-ray diffractometer, thermo gravimetric analysis and differential scanning calorimetry, Fourier transform infrared spectroscopy, scanning electron microscopy, vibrating sample magnetometer, and UV-Visible spectroscopy to study their structural, thermal, morphological, magnetic, and optical properties, respectively. The x-ray diffraction confirms the formation of single-phase inverse spinel cubic structure of NiFe3 O 4 nanoparticles. Crystallite size has been estimated by the full width at half maximum of the most intense x-ray diffraction peak where vibrational and stretching modes of metal-oxygen bonds in 872 cm are shown in Fourier transform infrared spectra which confirms the formation of nanoparticles. The thermal analysis revealed that the transition temperature and stability increases with increasing Ni concentration. The surface morphology indicated that the particles are spherical in shape with some agglomeration. The magnetic measurement revealed that the coercivity and anisotropy increases with nickel doping in magnetite nanoparticles. The optical analysis revealed that direct and indirect both types of band gap increases when the particle size decreases because the absorption spectra shift toward smaller wavelength. The blue shift confirms the formation of nanoparticles. 相似文献
60.
Ahmad Nisar Asif Hafiz Muhammad Shahzad Saleem Gulshan Younus Muhammad Usman Anwar Sadia Anjum Muhammad Rizwan 《Wireless Personal Communications》2021,121(2):1139-1168
Wireless Personal Communications - Identification of plant disease is usually done through visual inspection or during laboratory examination which causes delays resulting in yield loss by the time... 相似文献