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91.
The production of 123I from 123Te by the l23Te(p, n)123I reaction at various target enrichments (99.9, 91, 85.4, and 70.1%) was simulated using ALICE and SRIM programs. The 123I production feasibility by the above reaction was evaluated. The calculations give more accurate results for proton beam
energy of less than 30 MeV. The cross sections of all tellurium reactions with proton were calculated at 0–30 MeV proton beam
energy with ALICE program, and the yield of 123I was calculated by analytical methods. Our prediction for 123I production via bombardment of 123Te (99.9%) with a proton beam energy of 5–15 MeV is about 7.2 mCi μA−1 h−1.
Published in Russian in Radiokhimiya, 2008, Vol. 50, No. 5, pp. 460–463.
The text was submitted by the authors in English. 相似文献
92.
Mohammad Mojtaba Sadeghi Mohamed F. Salama Yusuf A. Hannun 《International journal of molecular sciences》2021,22(11)
Driver-directed therapeutics have revolutionized cancer treatment, presenting similar or better efficacy compared to traditional chemotherapy and substantially improving quality of life. Despite significant advances, targeted therapy is greatly limited by resistance acquisition, which emerges in nearly all patients receiving treatment. As a result, identifying the molecular modulators of resistance is of great interest. Recent work has implicated protein kinase C (PKC) isozymes as mediators of drug resistance in non-small cell lung cancer (NSCLC). Importantly, previous findings on PKC have implicated this family of enzymes in both tumor-promotive and tumor-suppressive biology in various tissues. Here, we review the biological role of PKC isozymes in NSCLC through extensive analysis of cell-line-based studies to better understand the rationale for PKC inhibition. PKC isoforms α, ε, η, ι, ζ upregulation has been reported in lung cancer, and overexpression correlates with worse prognosis in NSCLC patients. Most importantly, PKC isozymes have been established as mediators of resistance to tyrosine kinase inhibitors in NSCLC. Unfortunately, however, PKC-directed therapeutics have yielded unsatisfactory results, likely due to a lack of specific evaluation for PKC. To achieve satisfactory results in clinical trials, predictive biomarkers of PKC activity must be established and screened for prior to patient enrollment. Furthermore, tandem inhibition of PKC and molecular drivers may be a potential therapeutic strategy to prevent the emergence of resistance in NSCLC. 相似文献
93.
In supply chain management (SCM), multi-product and multi-period models are usually used to select the suppliers. In the real world of SCM, however, there are normally several echelons which need to be integrated into inventory management. This paper presents a hybrid intelligent algorithm, based on the push SCM, which uses a fuzzy neural network and a genetic algorithm to forecast the rate of demand, determine the material planning and select the optimal supplier. We test the proposed algorithm in a case study conducted in Iran. 相似文献
94.
Kazem M. Sadeghi Mohammad-Ali Sadeghi Teh Fu Yen 《Petroleum Science and Technology》1990,8(7):769-791
Reducible aromatic species in coal liquid products from five major processes (Synthoil, FMC COED, HRI H-Coal, PAMCO SRC, and Catalytic Inc. SRC) together with solvent elution chromatography fractions of a selected asphaltene has been evaluated. The half-wave potentials measurments are found to be consistant with other methods. The total polarographic reduction of measurement per average molecule for Synthoil solvent fractions, as measured by diffusion constant (id/C), increases in the following manner: gas oil → resin → asphaltene → carbene → carboid. The same trend was observed when color indices (I) and refractive indices (n25) were individually studied. 相似文献
95.
The oxidation of alcohols with tert-butylhydroperoxide (TBHP), in the presence of Mn2+ complexes immobilized in the pore channels of mesoporous hexagonal molecular sieves (HMS), were investigated. It was found that immobilized [Mn(bpy)2]2+/HMS is an efficient catalyst for the oxidation of alcohols such as benzyl alcohol, n-hexanol and cyclohexanol. The effects of reaction time, amount of Mn2+ in the catalyst, type of substrates and oxidants in this catalysis system were investigated. At optimum conditions, TBHP is more efficient oxidant with respect to H2O2. Following order has been observed for the percentage of conversions of alcohols: benzylic >1° >2°. 相似文献
96.
Masoud HomayouniTabrizi Mozhgan Soltani Ehsan Karimi Farideh Namvar Vahid Pouresmaeil Ali Eshaghi 《IET nanobiotechnology / IET》2019,13(6):617
One of the most important challenges in treating cancer is the invasion and the angiogenesis of cancer cells. The synthesis of green nanoparticles (NPs) and their use in therapeutic fields is one of the most effective methods with minimal side effects in cancer treatment. In this study, cytotoxic and anti‐angiogenic effects of silver NPs (AgNPs) coated with palm pollen extract [Ag–PP(NPs)] were evaluated. For this purpose, the cells were treated with NPs and then were subjected to trypan blue testing (48 h). Then, the cancer invasion was evaluated by the scratch procedure and the expressions of the vascular endothelial growth factor (VEGF) and its receptor (VEGF‐R) genes were estimated using real‐time PCR assay. Also, the angiogenesis effect of the NPs was investigated with chick chorioallantoic membrane (CAM) assay. The Ag–PP(NPs) induced cytotoxicity on MCF7 cells. The findings also showed that Ag–PP(NPs) inhibit invasive cancer cells and reduce the expression of VEGF and VEGF‐R and significantly reduced the number and vessels lengths and the lengths and weights of the embryos in CAM assay. Ag–PP(NPs) with the induction of cytotoxic effects, metastatic inhibition and anti‐angiogenesis properties should be considered as an appropriate option for treatment of cancerInspec keywords: nanomedicine, genetics, cellular biophysics, toxicology, patient treatment, silver, cancer, biochemistry, biomedical materials, nanoparticles, nanofabrication, membranesOther keywords: minimal side effects, cancer treatment, silver NPs, cancer invasion, vascular endothelial growth factor, receptor genes, VEGF‐R, real‐time polymerase chain reaction assay, angiogenesis effect, chick chorioallantoic membrane assay, MCF7 cells, invasive cancer cells, cytotoxic effects, putative mechanism, anticancer properties, antiangiogenic effects, antiangiogenesis properties, Ag–PP‐induced cytotoxicity, metastatic inhibition, palm pollen extraction, trypan blue testing, time 48.0 hour, Ag 相似文献
97.
Kinetic study of styrene atom transfer radical polymerization from hydroxyl groups of graphene nanoplatelets: Heterogeneities in chains and graft densities
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Hossein Roghani‐Mamaqani Vahid Haddadi‐Asl Khezrollah Khezri Mehdi Salami‐Kalajahi Mohammad Najafi 《Polymer Engineering and Science》2015,55(8):1720-1732
Confinement effect of graphene nanoplatelets on the kinetics of styrene atom transfer radical polymerization was studied by a “grafting from” reaction. Graphene oxide was modified by different amounts of (3‐aminopropyl) triethoxysilane and then alpha‐bromoisobutyryl bromide from the hydroxyl groups. Polymerization of styrene in the presence of modified graphene and free initiator, ethyl alpha‐bromoisobutyrate, was accomplished at 110°C. Then, effect of various graft densities and different graphene loadings on the heterogeneous graft and free polystyrene chains characteristics and also kinetics of polymerization was studied by gas and gel permeation chromatographies. Efficiency of grafting reactions along with the graft contents was studied by X‐ray photoelectron spectroscopy, elemental analysis, and thermogravimetric analysis. Confinement effects of graphene on the relaxation behavior of polystyrene chains and also morphology of the graphenes were studied by differential scanning calorimetry and transmission electron microscopy, respectively. POLYM. ENG. SCI., 55:1720–1732, 2015. © 2014 Society of Plastics Engineers 相似文献
98.
99.
Seyed Vahid Ebadi Aref Fakhrali Ali Akbar Gharehaghaji Saeedeh Mazinani Seyed Omid Ranaei‐Siadat 《Polymer Composites》2016,37(11):3149-3159
In this research, nanocomposite nanofibrous webs of poly(acrylic acid) (PAA)/multi‐walled carbon nanotubes (MWNTs) were obtained via electrospinning. The effect of MWNTs concentration on the morphology and mechanical properties of PAA/MWNTs nanofibers was investigated by changing the MWNTs content from 0 to 5 wt%. The results showed that average diameter of nanofibers increased with increasing the MWNTs concentration and presence of MWNTs led to the enhancement of mechanical properties. Also, the results revealed that the strength, modulus, and elongation at break of samples increased 3.22, 2.70, and 4.27 fold, respectively, after adding 3 wt% of MWNTs. In addition, the effect of rotating speed of collector on the orientation of PAA nanofibers and its effect on mechanical properties was investigated. Scanning electron microscopy (SEM) studies demonstrated that the degree of nanofibers orientation increased with the augmentation of drum speed to 25 rps. Moreover, the average nanofibers diameter decreased with the increase of drum speed. Improvement of nanofiber orientation resulted in superior mechanical properties that is, higher strength and modulus of aligned nanofiber layers were obtained in comparison to nonaligned layers (12.6 and 26.6 fold, respectively). POLYM. COMPOS., 37:3149–3159, 2016. © 2015 Society of Plastics Engineers 相似文献
100.
A new class of alternate aromatic poly(ether‐urea)s having bulky phenoxy phenyl lateral groups was prepared by the reaction of 2,2′‐bis[(p‐phenoxy phenyl)]‐4,4′‐diaminodiphenyl ether (PPAPE) with two diisocyanates, isophorone diisocyanate and 2,4‐tolylene diisocyanate. The limited viscosity values as well as M n and M w values of the resulting polymers were determined. The resulting poly(ether‐urea)s could be easily cast into optically‐transparent, flexible, and light color films. The cut‐off wavelength values and the percentage of transmittance at 800 nm were found to be at about 415 nm and 85%, respectively. PPAPE‐derived poly(ether‐urea)s showed a low‐crystallinity and had excellent solubility in polar organic solvents. Tonset, Tg, Td5%, and Td10% values of the PPAPE‐derived polymers measured from their DSC and TGA thermograms were up to 270, 280, 315, and 340°C, respectively. Surface morphology of the resulted poly(ether‐urea)s were also evaluated by their scanning electron microscopy images. Excellent organo‐solubility, satisfactory film quality, moderate Tg values, and good thermal stability make this class of poly (ether‐urea)s promising high‐performance polymeric materials. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献