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631.
This paper describes the simulation of a simple technique of superresolution based on holographic imaging in spectral domain. The input beam assembly containing 25 optical fibers with different orientations and positions is placed to illuminate the object in the 4f optical system. The position and orientation of each fiber is calculated with respect to the central fiber in the array. The positions and orientations of the fibers are related to the shift of object spectrum at aperture plane. During the imaging process each fiber is operated once in the whole procedure to illuminate the input object transparency which gives shift to the object spectrum in the spectral domain. This shift of the spectrum is equal to the integral multiple of the pass band aperture width. During the operation of single fiber (ON-state) all other fibers are in OFF-state at that time. The hologram recorded by each fiber at the CCD plane is stored in computer memory. At the end of illumination process total 25 holograms are recorded by the whole fiber array and by applying some post processing and specific algorithm single super resolved image is obtained. The superresolved image is five times better than the band-limited image. The work is demonstrated using computer simulation only. 相似文献
632.
633.
Kadhim H. Al-obaidi Basem F. Ali Rajab Abu-El-Halawa Anwar Abo-Amer 《Transition Metal Chemistry》2004,29(7):804-811
Mono- and dinuclear Cu(I) and Cu(II) complexes of 1,3,4-mercapto-oxadiazole derivatives were prepared and characterized by elemental analyses and standard spectroscopic techniques. The complexes were formulated as Cu(G-OX)2, Cu2(G-OX)4(H2O)4, Cu(G-OX)2L2and Cu2(G-OX)2(PPh3)2; (G = H, MeO, Cl; L = Ph3P, Ph3As). The microbiological activity of the complexes was investigated against bacteria and fungi. All the complexes were active against Candida albicans, while the reactivity against bacteria varied. The antimicrobial activity of the [Cu(MeO-OX)2(H2O)2]2 complex was exceptionally better than that observed for any other metal complex against both bacteria and fungi. 相似文献
634.
Kamal Tahseen Khan Sher Bahadar Bakhsh Esraa M. Anwar Yasir 《Cellulose (London, England)》2021,28(17):11067-11080
Cellulose - In this research work, we present a synthesis of silver and cobalt bimetal nanoparticles stabilized by a carboxymethyl cellulose biopolymer (CMC-AgCo) and its coating on a cellulose... 相似文献
635.
Anwar Saeed Niqab Khan Taza Gul Wiyada Kumam Wajdi Alghamdi Poom Kumam 《Molecules (Basel, Switzerland)》2021,26(21)
This research work aims to scrutinize the mathematical model for the hybrid nanofluid flow in a converging and diverging channel. Titanium dioxide and silver are considered as solid nanoparticles while blood is considered a base solvent. The couple-stress fluid model is essentially use to describe the blood flow. Therefore, the couple-stress term was used in the recent study with the existence of a magnetic field and a Darcy–Forchheiner porous medium. The heat absorption/omission and radiation terms were also included in the energy equation for the sustainability of drug delivery. An endeavor was made to link the recent study with the applications of drug delivery. It has already been revealed by the available literature that the combination of with any other metal can destroy cancer cells more effectively than separately. Both the walls are stretchable/shrinkable, whereas flow is caused by a source or sink with α as a converging/diverging parameter. Governing equations were altered into the system of non-linear coupled equations by using the similarity variables. The homotopy analysis method (HAM) was applied to obtain the preferred solution. The influences of the modeled parameters have been calculated and displayed. The confrontation of wall shear stress and hybrid nanofluid flow increased as the couple stress parameter rose, which indicates an improvement in the stability of the base fluid (blood). The percentage (%) increase in the heat transfer rate with the variation of nanoparticle volume fraction was also calculated numerically and discussed theoretically. 相似文献
636.
Elaheh Konoz Ashraf Abbasi Roudabeh Sadat Moazeni Hadi Parastar Mehdi Jalali-Heravi 《Journal of the Iranian Chemical Society》2013,10(1):169-179
Iranian olive leaf essential oil components were extracted by microwave-assisted hydrodistillation and analyzed using gas chromatography-mass spectrometry. Ninety-seven components were identified by direct similarity searches for olive leaf essential oil. Chemometrics was used to find more components with the help of multivariate curve resolution methods. Eigenvalues-based methods and Malinowski functions were used for chemical rank determination of GC–MS data. Multivariate curve resolution-alternative least squares as an iterative method was used for resolving the overlapped and embedded peaks. With the use of this method the number of 97 components was extended to 127 components. Major constituents in the olive leaf essential oil are 2-decenal-(E) (20.43 %), benzeneacetaldehyde (4.00 %), 2-undecenal (3.71 %) and valencen (3.31 %). 相似文献
637.
Suchada Chantrapromma Anwar Usman Hoong‐Kun Fun 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):m534-m536
The molecule of the title compound {systematic name: di‐μ‐sulfido‐bis[diaqua(1,4,7,10,13,16‐hexaoxacyclooctadecane‐κ6O)barium(II)] bis[1,2‐benzisothiazol‐3(2H)‐one 1,1‐dioxide]}, [Ba2S2(C12H24O6)2(H2O)4](C7H5NO3S)2, lies on an inversion centre. The BaII atom encapsulated by the 18‐crown‐6 ring is coordinated by the six O atoms of the crown, two water O atoms and two bridging S atoms. The four‐membered ring composed of the BaII atoms and the bridging S atoms makes a dihedral angle of 67.1 (1)° with the crown‐ether ring. The aromatic ring system of the saccharin moiety is essentially planar. The packing is built up from layers of the molecules and is stabilized by three intermolecular O—H?O hydrogen bonds. 相似文献
638.
Steam distilled oils of some species of the genus Citrus and Cymbopogon citratus were analyzed by GC-MS. It is observed that citral b was the most common constituent of the oils, which could be a good inhibitor of beta-glucuronidase as all the tested essential oils showed significant inhibition of beta-glucuronidase. IC50 values of a mixture of citral a and b also proved the hypothesis. The same oils also exhibited positive response against tested microbes. 相似文献
639.
Variation in antioxidant attributes at three ripening stages of guava (Psidium guajava L.) fruit from different geographical regions of Pakistan 总被引:1,自引:0,他引:1
Gull J Sultana B Anwar F Naseer R Ashraf M Ashrafuzzaman M 《Molecules (Basel, Switzerland)》2012,17(3):3165-3180
The present investigation was carried out to appraise the levels of total phenols and vitamin C as well as antioxidant potential at three different ripening stages (un-ripe, semi-ripe and fully-ripe) of guava (Psidium guajava L.) fruit collected from three different geographical regions of Pakistan (Islamabad, Faisalabad and Bhakkar). The antioxidant potential of guava fruit extracts was assessed by means of different in-vitro antioxidant assays, namely inhibition of peroxidation in linoleic acid system, reducing power and radical scavenging capability. Overall, fruit at the un-ripe stage (G1) exhibited the highest levels of TPC, TFC, reducing power and DPPH radical scavenging activity, followed by the semi-ripe (G2) and fully-ripe (G3) stages. On the other hand, vitamin C content increased as the fruit maturity progressed, with highest value seen at the fully-ripe stage (G3) followed by the semi-ripe (G2) and un-ripe stage (G1). The concentration of vitamin C in fruits varied as: Faisalabad (136.4-247.9 mg 100 g?1), Islamabad (89.7-149.7 mg 100 g?1) and Bhakkar (73.1-129.5 mg 100 g?1). The results showed that different stages of maturation and geographical locations had profound effects on the antioxidant activity and vitamin C contents of guava fruit. 相似文献
640.
Activation of C2 and C3 of indoles by molecular iodine (I(2)) and base followed by in situ reaction with 1-(2-tosylaminophenyl)ketones or 2-tosylaminobenzaldehyde can afford highly substituted indolo(2,3-b)quinolines in moderate to excellent yields (up to 99%). The reaction provides a metal-free selective difunctionalization of indoles. The synthetic potential of the protocol has been illustrated by the synthesis of neocryptolepine and its 11-methyl analogue. 相似文献