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1.
Saleh Ashrafi Okhtay Jahanbakhsh Davood Alizadeh Behrooz Salehpour 《Central European Journal of Physics》2013,11(5):560-567
Compton scattering tomography is widely used in numerous applications such as biomedical imaging, nondestructive industrial testing and environmental survey, etc. This paper proposes the use of the genetic algorithm (GA), which utilizes bio-inspired mathematical models, to construct an image of the insides of a test object via the scattered photons, from a voxel within the object. A NaI(Tl) scintillation detector and a 185 MBq 137Cs gamma ray source were used in the experimental measurements. The obtained results show that the proposed GA based method performs well in constructing images of objects. 相似文献
2.
Hamid?GoudarziafsharEmail author Majid?Rezaeivala Fayezeh?Khosravi Yunes?Abbasityula Somaieh?Yousefi Neslihan??zbek Václav?Eigner Michal?Du?ek 《Journal of the Iranian Chemical Society》2015,12(1):113-119
The ligand 1,2-dimorpholinoethane (DME) was used to prepare Zn(II) and Ni(II) complexes of the general formulation MLX2 (L = DME, X = Cl or NO3). Zinc(II) complex exhibits spectral properties indicative of a distorted tetrahedral geometry, with DME coordinating through two nitrogen atoms and two chlorides completing the tetrahedron. This is in contrast to the six-coordinated, distorted octahedral geometry exhibited by nickel(II) complex of DME when NO3 was used as counter ions. The X-ray diffraction confirms the structures of two complexes and shows that the ligand coordinates through two nitrogen atoms while the two ether linkages are not involved in complexation, which would have been the case if the morpholine rings were in the boat form. The ligand and related complexes have antibacterial activity against the five Gram-positive bacteria: Bacillus subtilis ATCC 6633, Staphylococcus aureus ATCC 6538, Bacillus cereus NRRL-B-3711, Enterococcus faecalis ATCC 29212 and Streptococcus pyogenes and also against the three Gram-negative bacteria: Escherichia coli ATCC 11230, Pseudomonas aeruginosa ATCC 15442 and Klebsiella pneumonia ATCC 70063. The results showed that in some cases the antibacterial activity of the complexes exceeded the one of sulfisoxazole used as a standard. 相似文献
3.
Alireza Khorsandi Saeed Ghavami Sabouri Somaieh Fathi Marzieh Asadnia-Jahromi 《Optics & Laser Technology》2011,43(5):956-959
We have reported a modified V-shaped external cavity, which is constructed around a commercial diode laser operating at a center wavelength of λ=785 nm by adding a new coated glass plate with about 50% reflectivity to the cavity. This allows simultaneous dual-wavelengths operation in the vicinity of Δνmin=0.18 THz to Δνmax=0.22 THz, which can be used as laser source for terahertz generation either for semiconductor devices or nonlinear schemes. 相似文献
4.
Morteza Sadeghi Homayoon Moadel Somaieh Khatti Behnam Ghalei 《Journal of Macromolecular Science: Physics》2013,52(6):1128-1135
The sorption behaviors of sulfuric, perchloric, and phosphoric acids in polybenzimidazole membranes have been investigated. The results of sorption isotherms are consistent with the general form of a dual-mode sorption isotherm. The dual-mode sorption parameters were found using a least-squares program by fitting experimental data to a dual-mode equation. Results indicate a correlation between permeant properties like acidity, size, and the affinity constant in Langmuir-mode sorption species. Moreover, the results show that the size of the permeants has the dominant effect on Henry's constant. The obtained results for , site saturation constant, in Langmuir-mode sorption in the case of perchloric and phosphoric acids, reveals that the two acid molecules interact with two N?H basic groups in the polybenzimidazole repeat units. But in the case of sulfuric acid, it is shown that sulfuric acid neutralizes some of the basic groups in the polymer by its strong second hydrogen and the obtained value for was 1.25. 相似文献
5.
Nasir Iravani Jalal Albadi Somaieh Varnaseri Zahra Jaberi Nahid Karami Marzieh Khadamati 《中国化学会会志》2012,59(12):1567-1570
A simple and efficient one‐pot synthesis of alkyl 2‐(alkyl)‐4‐methyl‐2‐thioxo‐2,3‐dihydrothiazole‐5‐carboxylates from the reaction of primary alkylamines and carbon disulfide in the presence of 2‐chloro‐1,3‐dicarbonyl compounds is described. This new protocol has several advantages such as lack of necessity of the catalyst, good yields, mild conditions and short times for reaction. 相似文献
6.
Alexander Fauland Martin Trötzmüller Anita Eberl Somaieh Afiuni‐Zadeh Harald Köfeler Xinghua Guo Ernst Lankmayr 《Journal of separation science》2013,36(4):744-751
This work reports an efficient and universal SPE method developed for separation and identification of phospholipids derived from complex biological samples. For the separation step, sequential combination of silica gel‐aminopropyl‐silica gel SPE cartridges is applied. This setup enables separation of phosphatidylcholine, lysophosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol, phosphatidic acid, phosphatidylinositol, phosphatidylserine, cardiolipin, and sphingomyelin into four fractions according to the polarity of their headgroups. Sample acquisition of the SPE fractions is performed by a high‐resolution LC‐MS system consisting of a hybrid linear IT Fourier transform ion cyclotron resonance mass spectrometer coupled to RP‐HPLC. The unequivocal advantage of our SPE sample preparation setup is avoidance of analyte peak overlapping in the determination step done by RP‐HPLC. Overlapping phospholipid signals would otherwise exert adverse ion suppression effects. An additional benefit of this method is the elimination of polar and nonpolar (e.g. neutral lipids) contaminants from the phospholipid fractions, which highly reduces contamination of the LC‐MS system. The method was validated with fermentation samples of organic waste, where 78 distinct phospholipid and sphingomyelin species belonging to six lipid classes were successfully identified. 相似文献
7.
Transient state swelling behavior and swelling kinetics of novel stimuli-responsive polyglycerol hydrogels were studied at 293, 310 and 333 K. Depending on temperature, Fickian or anomalous diffusion behavior was observed. Mechanical properties of the hydrogels in the swollen and dry states were investigated and the average molecular weight between crosslinks was calculated. To assess the potential for biodegradation of hydrogels, initial swelling behavior in phosphate buffered saline (PBS) solution and mass loss profiles as a function of degradation time were investigated over a period of 30 days. All swelling behavior, mechanical properties and degradations were clearly affected by the degree of cross-linking. The hydrophilicity and biodegradability of polyglycerol hydrogels make them suitable for pharmaceutical, biomedical and biotechnological applications. They could potentially serve as a substitute for common fossil-based hydrogels such as poly(ethylene glycol) and poly(vinyl alcohol) hydrogels. 相似文献
8.
Goudarziafshar Hami Yousefi Somaieh Abbasityula Yunes Duek Michal Eigner Vclav Rezaeivala Maji zbek Neslihan 《无机化学学报》2015,31(6):1076-1084
以1,3-二吗啉基丙烷(DMP)为配体合成了2个配合物:Hg(DMP)Cl2(1)和Zn(DMP)Cl2(2),并对其结构进行了表征。单晶X-射线结构分析表明,2个配合物中的金属离子都与2个N原子和2个Cl原子配位,形成扭曲四面体配位结构。配体和配合物对3种革兰氏阳性菌(S. aureus ATCC25923,E. faecalis ATCC23212和S. epidermidis ATCC34384)和3种革兰氏阴性菌(E. coli ATCC25922,P. aeruginosa ATCC27853和K. pneumonia ATCC70063)都具有抗菌活性,且在一定条件下,Hg(Ⅱ)配合物的抗菌活性超过了作为标准的磺胺异恶唑药物。 相似文献
9.
Reza Mahmoudi Saeed Aghaei Zeinab Salehpour Ali Mousavizadeh Seyed Sajjad Khoramrooz Marzie Taheripour Sisakht Gunna Christiansen Marzieh Baneshi Bahman Karimi Hassan Bardania 《应用有机金属化学》2020,34(2):e5394
Due to environmentally friendly and cost- effective issues, biological methods for silver nanoparticles (AgNPs) synthesis are advantageous over chemical and physical ones. In this study, AgNPs synthesized using Lavandula stoechas extract as a reductant and its antioxidant capacity, antibacterial property and cytotoxicity effect were investigated. The phyto-synthesized AgNPs were characterized using various analyses such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), x-ray diffraction (XRD) as well as Fourier transform infrared (FT-IR). The prepared nanoparticles were spherical on shape with the size about 20–50 nm. Antibacterial studies through agar disk diffusion method confirmed the antibacterial potential of phyto-synthesized AgNPs toward two clinical Staphylococus aureus and Pseudomonas aeruginosa bacteria, although MTT assay demonstrated that S. aureus (MIC = 125 μg/ml) was more susceptible to AgNPs than P. aeruginosa (MIC = 250 μg/ml). Moreover, the cytotoxicity assay of phyto-synthezied AgNPs showed a low cytotoxic effect on RAW264 cell line at 62.5 μg/ml as an effective concentration. Also the considerable antioxidant capacity of the AgNPs confirmed through DPPH assay. Great antibacterial and antioxidant properties along with biocompatibility make the suggested phyto-synthesized AgNPs a great candidate for different biomedical applications including wound healing. 相似文献
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