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41.
M. Y. Raie A. Manzoor S. A. Khan A. H. Chaudhry 《European Journal of Lipid Science and Technology》1983,85(6):238-239
The fatty acid percentage-wise composition of Sisymbrium irio and Camelina sativa as determined by GLC, containing 22.0% and 23.0% oil respectively, is C14:0 (0.7, 0.5), C16:0 (15.8, 9.0), C18:0 (3.5, 2.8), C18:1 (17.2, 20.7), C18:2 (15.6, 22.9), C18:3 (37.1, 34.3), C20:0 (0.0, 2.0), C20:1 (0.0, 7.8) and C22:1 (10.1, 0.0). 相似文献
42.
A highly accurate method of optical path-length measurement is introduced by use of a scanning heterodyne optical interferometer with no moving parts. The instrument has demonstrated the potential to measure optical path length at angstrom resolution over continuous thickness in the micrometer range. This optical path length can be used to calculate the thickness of any material if the refractive index is known or to measure the refractive index of the material if the thickness is known. The instrument uses a single acousto-optic device in an in-line ultra-stable reflective geometry to implement rapid scanning in the microsecond domain for thickness measurements of the test medium. 相似文献
43.
Khan Muhammad Imran Dong Huang Shabbir Faisal Shoukat Rizwan 《Microsystem Technologies》2018,24(2):869-877
Microsystem Technologies - Electronic devices are shrinking day by day, while the speed and reliability is increasing. At the same time, IC designs and micro/nano electronic systems are becoming... 相似文献
44.
Mohd Yousuf Dar Wajaht A. Shah Manzoor A. Rather Yasrib Qurishi Abid Hamid M.A. Qurishi 《Food chemistry》2011
The chemical composition of the hydrodistillate of aerial parts of Cymbopogon jawarancusa, a natural grass considered as major forage for animal nutrition, used in food because of the presence of sufficient concentration of minerals like calcium and potassium was analysed by capillary GC–FID, GC–MS and 13C NMR. Seventeen constituents representing 97.8% of the total oil with piperitone (58.6%) and elemol (18.6%) as major constituents were identified. In vitro cytotoxicity of the oil and its constituents on human cancer cell lines THP-1 (leukemia), A-549 (lung), HEP-2 (liver) and IGR-OV-1 (ovary) was evaluated by Sulphorhodamine-B assay. The oil was found to be more potent than its components against cancer cell lines tested with IC50 of 6.5 μg/ml (THP-1), 6.3 μg/ml (A-549), 7.2 μg/ml (HEP-2) and 34.4 μg/ml (IGR-OV-1). Antioxidant activity of oil and its constituents was evaluated by DPPH assay. In conclusion, the results demonstrate potent cytotoxic and antioxidant effects of oil, and its components like piperitone, α-pinene, β-caryophyllene and β-elemene. 相似文献
45.
Tasneem G. Kazi Nusrat Jalbani Jameel A. Baig Mohammad B. Arain Hassan I. Afridi Mohammad K. Jamali Abdul Q. Shah Allah N. Memon 《Food chemistry》2010
In present work, the concentrations of toxic elements, aluminium (Al), cadmium (Cd), nickel (Ni) and lead (Pb) were measured in different solid baby foods (BFs), primarily to evaluate whether the intakes comply within permissible levels of these toxic elements (TEs). The BFs were evaluated for total contents of TEs, using a simple and fast ultrasound-assisted extraction (UAE) method. The accuracy of the proposed UAE method was ensured by using certified reference materials and results obtained by conventional wet acid digestion method on same CRM, at 95% confidence level. The range of the investigated TEs in different BFs were 4770–35,200, 25.6–88.3, 124–332 and 52.5–90.6 μg/kg for Al, Cd, Ni and Pb, respectively. The results indicated that BFs including rice cereals have high level of all four TEs. The daily intakes of TEs for children through BFs have also been estimated, and are well below the recommended tolerable levels. 相似文献
46.
47.
Guoqing Guan Marion Teshima Chie Sato Sung Mo Son Muhammad Faisal Irfan Katsuki Kusakabe Norihiro Ikeda Tsao‐Jin Lin 《American Institute of Chemical Engineers》2010,56(5):1383-1390
Flow patterns in the course of transesterification of waste cooking oil (WCO), sunflower oil (SFO) with water and/or oleic acid as a model of WCO, and pure SFO in the presence of a KOH catalyst in microtubes were investigated. FAME yield for the transesterification of WCO reached more than 89% in the microtube reactors with a residence time of 252 s at 333 K. The flow patterns when using WCO were changed from a liquid–liquid slug flow at the inlet region to a parallel flow at the middle region, and then to a homogeneous liquid flow at the outlet region as the reaction proceeded at 333 K. Fine droplets containing glycerol and methanol generally formed in oil slugs when using pure SFO, but were almost unobservable when using WCO. The soap produced from free fatty acids was considered to be the main factor affecting the flow patterns of WCO and SFO. © 2009 American Institute of Chemical Engineers AIChE J, 2010 相似文献
48.
The present investigation aims to explore the influence of a mixed convection and nonuniform heat source/sink on unsteady flow of a chemically reactive nanofluid driven by a bidirectionally expandable surface. Convective heat transport phenomenon is used to maintain the temperature of the surface. Moreover, zero mass flux is also accounted at the surface such that the fraction of nanomaterial maintains itself on strong retardation. The governing nonlinear set of partial differential equations is transformed into a set of ordinary differential equations via a suitable combination of variables. The Keller‐Box scheme has been incorporated to make a numerical inspection of the transformed problem. The spectacular impacts of the pertinent constraints on thermal and concentration distributions are elucidated through various plots. Graphical outcomes indicate that the thermal state of nanomaterial and nanoparticles concentration are escalated for elevated amounts of Biot number, porosity parameter and nonuniform heat source/sink constraints. Furthermore, it is also seen that escalating amounts of unsteady parameter, temperature controlling indices, Prandtl number, and expansion ratio parameter reduce the thermal and concentration distributions. Numerical results for the rate of heat transference have been reported in tabular form. The grid independence approach is used to verify the convergence of the numerical solution and the CPU run time is also obtained to check the efficiency of the numerical scheme adopted for finding the solution. 相似文献
49.
The thermal and hydraulic performance of a modified two-stage evaporative cooler is evaluated. Variables considered are the mode of operation, packing thickness, mass flow rate of the water flowing to the precooler, and the mass flux of water flowing over the packing media. The effectiveness of the system increased with the increase of the mass flow rate of water flowing to the precooler, decreasing the mass flux of water flowing to the packing, and with the increase of the packing thickness. The effectiveness of the system with structured packing was higher than that with sheathy leaf base or natural fiber packing.The air-side pressure drop per unit length in the direction of air flow was nearly constant when the structured packing was used. For the sheathy leaf and natural fiber packings, the air pressure drop increased at a uniform rate as the mass flux of water flowing over the packing increased. The air pressure drop was lowest for the setup with the structured packing. 相似文献
50.
Zara Hamid Faisal Bashir Hussain Jae-Young Pyun 《Multimedia Tools and Applications》2016,75(14):8195-8216
Wireless Multimedia Sensor Networks (WMSNs) consist of networks of interconnected devices involved in retrieving multimedia content, such as, video, audio, acoustic, and scalar data, from the environment. The goal of these networks is optimized delivery of multimedia content based on quality of service (QoS) parameters, such as delay, jitter and distortion. In multimedia communications each packet has strict playout deadlines, thus late arriving packets and lost packets are treated equally. It is a challenging task to guarantee soft delay deadlines along with energy minimization, in resource constrained, high data rate WMSNs. Conventional layered approach does not provide optimal solution for guaranteeing soft delay deadlines due to the large amount of overhead involved at each layer. Cross layer approach is fast gaining popularity, due to its ability to exploit the interdependence between different layers, to guarantee QoS constraints like latency, distortion, reliability, throughput and error rate. The paper presents a channel utilization and delay aware routing (CUDAR) protocol for WMSNs. This protocol is based on a cross-layer approach, which provides soft end-to-end delay guarantees along with efficient utilization of resources. Extensive simulation analysis of CUDAR shows that it provides better delay guarantees than existing protocols and consequently reduces jitter and distortion in WMSN communication. 相似文献