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21.
Turan Nevin Buldurun Kenan Türkan Fikret Aras Abdulmelik Çolak Naki Murahari Manikanta Bursal Ercan Mantarcı Asim 《Molecular diversity》2022,26(5):2459-2472
Molecular Diversity - Schiff bases are well-known compounds for having significant biological properties. In this study, a new Schiff base ligand and its metal complexes were synthesized, and their... 相似文献
22.
Fikret Anli Faruk Ya?a Hakan Öztürk 《Journal of Quantitative Spectroscopy & Radiative Transfer》2006,101(1):129-134
The critical slab problem has been studied in one-speed neutron transport equation with isotropic scattering by using the TN method. TN moment criticality solutions are obtained for the uniform finite slab using Mark and Marshak type vacuum boundary conditions. Results obtained by TN method, using the two type boundary conditions mentioned above, were presented in the Tables and also the Tables included the results obtained by PN method for the comparisons. 相似文献
23.
Hakan Öztürk Fikret Anli 《Journal of Quantitative Spectroscopy & Radiative Transfer》2007,105(2):211-216
The critical slab problem in the case of combination of forward and backward scattering with usual isotropic scattering is studied for one-speed neutrons in a uniform finite slab by using TN method based on Chebyshev polynomial approximation and Marshak boundary conditions. It is shown that TN method gives accurate results in one-dimensional geometry and is very efficient both in derivation of equations and rapid convergence. Numerical results obtained by TN method are compared against the PN method in tabular form, which agreed quite well. 相似文献
24.
Fikret Kirkbir Hideaki Murata Douglas Meyers S. Ray Chaudhuri Arnab Sarkar 《Journal of Sol-Gel Science and Technology》1996,6(3):203-217
This review article summarizes the development of drying and sintering techniques for the production of sol-gel derived, large silica glass components. Gels may be synthesized using particulate or metal alkoxide precursors, or both in combination. Rapid fracture-free drying has been achieved easily with particulate gels because of their large pore size (100–6000 Å). Alkoxide gels, which generally have small pores (<200 Å), were initially difficult to dry without cracking. However, recent studies have shown that large alkoxide gel monoliths can also be dried in reasonably short times (<10 days). During subsequent heat treatment, alkoxide gels tend to have high shrinkage rates, which may cause trapping of hydroxyl ions or organic groups remaining on the gel surface. Although the removal of these species is easier for particulate gels, their large pore size necessitates heating above 1400°C to achieve full consolidation. Sintering at such temperatures was observed to deteriorate glass quality, through crystallization, warping, and/or sagging. Extensive optimization of the entire process has shown that on a laboratory scale, high-optical-quality glass can be produced from both alkoxide and particulate gels. It remains to be seen whether sol-gel process will be feasible for the manufacture of high-quality glass products on a commercial scale. 相似文献
25.
In this paper, we discuss the uniqueness in an integral geometry problem along the straight lines in a strongly convex domain. Our problem is related with the problem of finding a Riemannian metric by the distances between all pairs of the boundary points. For the proof, the problem is reduced to an inverse source problem for a kinetic equation and then the uniqueness theorem is proved using the tools of Fourier analysis. 相似文献
26.
Ping Huang Fikret Mamedov Stenbjörn Styring Esa Tyystjärvi 《Photochemistry and photobiology》2014,90(5):965-971
Singlet oxygen, a harmful reactive oxygen species, can be quantified with the substance 2,2,6,6‐tetramethylpiperidine (TEMP) that reacts with singlet oxygen, forming a stable nitroxyl radical (TEMPO). TEMPO has earlier been quantified with electron paramagnetic resonance (EPR) spectroscopy. In this study, we designed an ultra–high‐performance liquid chromatographic—tandem mass spectrometric (UHPLC‐ESI‐MS/MS) quantification method for TEMPO and showed that the method based on multiple reaction monitoring (MRM) can be used for the measurements of singlet oxygen from both nonbiological and biological samples. Results obtained with both UHPLC‐ESI‐MS/MS and EPR methods suggest that plant thylakoid membranes produce 3.7 × 10?7 molecules of singlet oxygen per chlorophyll molecule in a second when illuminated with the photosynthetic photon flux density of 2000 μmol m?2 s?1. 相似文献
27.
LetX be a locally compact non compact space. Necessary and sufficient conditions forfX/X to be a retract offX are given wherefX is the Freudenthal compactification ofX. LetX be a locally compact and zero dimensional space,m be any cardinal number andJ be a set with cardinalitym. It is proved thatX has a dyadic family of powerm if and only if there exist and compactificationY ofX such thatY/X=2 J andY/X is a retract ofY. 相似文献
28.
Highly branched polymers such as polyamidoamine (PAMAM) dendrimers are promising macromolecules in the realm of nanobiotechnology due to their high surface coverage of tunable functional groups. Modeling efforts of PAMAM can provide structural and morphological properties, but the inclusion of solvents and the exponential growth of atoms with generations make atomistic simulations computationally expensive. We apply an implicit solvent coarse‐grained model, called the Dry Martini force field, to PAMAM dendrimers. The reduced number of particles and the absence of a solvent allow the capture of longer spatiotemporal scales. This study characterizes PAMAM dendrimers of generations one through seven in acidic, neutral, and basic pH environments. Comparison with existing literature, both experimental and theoretical, is done using measurements of the radius of gyration, moment of inertia, radial distributions, and scaling exponents. Additionally, ion coordination distributions are studied to provide insight into the effects of interior and exterior protonation on counter ions. This model serves as a starting point for future designs of larger functionalized dendrimers. © 2015 Wiley Periodicals, Inc. 相似文献
29.
This study reports simultaneous quantification of both acylated and desacylated forms of ghrelin in biological samples, utilizing a reverse-phase high-performance liquid chromatography (HPLC) system. The HPLC assay was also compared with RIA assays in use. Biological samples (serum, saliva, urine, milk) known for the presence of ghrelin were collected from a total of eight post-partum women and eight male volunteers. Analysis of ghrelin with HPLC was also validated for linearity, precision, detection limit and accuracy. An elution time of 6 min was observed for pure (commercial) desacylated human ghrelin and for the same form of the hormone from all body fluids studied. The elution time for acylated pure human ghrelin and that in body fluids, however, was around 16 min. The mean recovery rate was over 90% for both forms with no significant interference. The lowest detectable levels for acylated and desacylated ghrelin with the method used here were 11 (+/-2) and 14 (+/-3) pg mL(-1), respectively. Given its simplicity, accuracy, time and cost-effectiveness, the HPLC method described here for determination of two forms of ghrelin (active and inactive) might prove useful for certain diagnostic purposes. 相似文献
30.
Buldurun Kenan Turan Nevin Bursal Ercan Mantarcı Asim Turkan Fikret Taslimi Parham Gülçin İlhami 《Research on Chemical Intermediates》2020,46(1):283-297
Research on Chemical Intermediates - Considering the importance of metal complexes in the development of medical science, two different Schiff base Fe(II) and Co(II) metal complex compounds were... 相似文献