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111.
Afaq Shagufta Khan Sadia Kazmi Mehdi Hassan Fatima Itrat Malik Abdul Inamullah Farah Farhad Zahid Abbas Tanveer Tareen Rasool Bakhsh 《Chemistry of Natural Compounds》2021,57(2):269-273
Chemistry of Natural Compounds - Armatans A (1) and B (2), new isoflavans, have been isolated from the EtOAc-soluble fraction of the MeOH extract of Colutea armata Hemsl. & Lace, along with... 相似文献
112.
113.
Mahdi Sadeghi Zahra Alipoor Abbas Majdabadi 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(3):745-751
The 82Sr/82Rb radionuclide generator is used very commonly in positron emission tomography. ALICE/ASH and TALYS 1.0 codes were used to calculate excitation functions for proton, alpha and 3He induced on various targets that lead to produce 82Sr radioisotope using intermediate energy accelerators. Recommended thickness of the targets according to SRIM code was premeditated. The application of those data, particularly in the calculation of integral yields, is discussed and theoretical integral yields for any reaction were computed. To consider precision of TALYS 1.0 code calculations, 85Rb(p,4n)82Sr process was determined as most interesting one due to radionuclide purity. The TALYS 1.0 code predicts a maximum cross-section of about 130 mb at 47 MeV for this reaction. Rubidium chloride deposition on copper substrate was carried out via sedimentation method in order to produce 82Sr. 2.98 g RbCl, 1.043 g ethyl cellulose, 10 mL acetone were used to prepare a layer of enriched rubidium chloride of 11.69 cm2 area and 0.34 g/cm2 thickness. 相似文献
114.
Mauro L. Bonardi Flavia Groppi Simone Manenti Elisa Persico Luigi Gini Kamel Abbas Uwe Holzwarth Federica Simonelli Zeev B. Alfassi 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):1-7
Very high specific activity (AS) 186gRe could be produced by either proton or deuteron cyclotron irradiation on highly enriched 186W target in no-carrier-added (NCA) form, leading to a AS very close to the theoretical carrier free (CF) value of 6.88 GBq μg−1. Thick Target Yields (TTYs), obtained irradiating both thick metal W targets of natural isotopic composition and highly enriched
powdered 186W targets, were measured at different particles energies taking into account high accuracy and precision. The evaluation of
radionuclidic purities of 186gRe obtained activating highly enriched 186W by both p and d were also carried out and accurately compared. The thin-target excitation functions for all Re (A = 181,
182, 183, 184, 186 and their metastable levels), and W and Ta coproduced radionuclides will be presented elsewhere in deep
details. 相似文献
115.
In this paper, we prove a local existence and uniqueness result for fuzzy delay differential equations driven by Liu process.
We also establish continuous dependence of solution with respect to initial data. 相似文献
116.
We obtain necessary conditions for the existence of fixed point and approximate fixed point of nonexpansive and asymptotically nonexpansive maps defined on a closed bounded convex subset of a uniformly convex complete metric space and study the structure of the set of fixed points. We construct Mann type iterative sequences in convex metric space and study its convergence. As a consequence of fixed point results, we prove best approximation results. We also prove Kantorovich-Rubinstein maximum principle in convex metric spaces. 相似文献
117.
In this study ground and excited states acidic dissociation constants of a recently synthesized Schiff base was obtained in a DMF:water mixture of 30:70 (v/v) using absorption and fluorescent spectra of the Schiff base in different pH values with the aid of chemometric methods. In addition, the fluorescent of the two kinds of tautomers of this Schiff base was investigated and the rate of tautomerization was obtained using rank annihilation factor analysis (RAFA). The effect of different kinds of surfactants such as sodium dodecyl sulfate (SDS), cetyltrimethylammonium bromide (CTAB) and Triton X-100 on fluorescence spectrum of the Schiff base in a DMF:water mixture of 2:98 (v/v) was investigated. CTAB increased the fluorescence intensity of the Schiff base while SDS and Triton X-100 had no significant effect on it. β-Cyclodextrin increased the fluorescence intensity of the Schiff base. Also the sensing behavior of this Schiff base toward metal ions was studied in DMF and ethanol by fluorescence spectroscopy. The Schiff base showed prominent fluorescent signal in the presence of Zn2+, whereas other metal ions failed to induce response and ground-state dissociation constant of the complex was determined by direct fluorimetric titration as a function of Zn2+ concentration. 相似文献
118.
In this paper, we introduce Pexiderized generalized operators on certain special spaces introduced by Bielecki-Czerwik and
investigate their norms. 相似文献
119.
120.
This work is concerned with the two-dimensional boundary layer flow of an upper-convected Maxwell (UCM) fluid in a channel
with chemical reaction. The walls of the channel are porous. Employing similarity transformations the governing non-linear
partial differential equations are reduced into non-linear ordinary differential equations. The resulting ordinary differential
equations are solved analytically using homotopy analysis method (HAM). Expressions for series solutions are derived. The
convergence of the obtained series solutions are shown explicitly. The effects of Reynold’s number Re, Deborah number De, Schmidt number Sc and chemical reaction parameter γ on the velocity and the concentration fields are shown through graphs and discussed. 相似文献