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71.
A two-step procedure including appropriate wet-digestions, separation of selenium from interfering ions such as heavy metal ions with pentyl alcohol and anodic stripping voltammetric (ASV) determination of Pb2+, Cu2+ and SeO3 2– is developed. The elements in digested whole blood and serum sample solutions were determined by using a standard addition method. 1 × 10–9 mol/L SeO2– 3, Cu2+ and Pb2+ were successfully determined with relative standard deviations of approximately 1–2% (n = 6–8). Received: 19 August 1996 / Revised: 24 February 1997 / Accepted: 28 February 1997  相似文献   
72.
Germanosilicate layers were grown on Si substrates by plasma enhanced chemical vapor deposition (PECVD) and annealed at different temperatures ranging from 700–1010 °C for durations of 5 to 60 min. Transmission electron microscopy (TEM) was used to investigate Ge nanocrystal formation in SiO2:Ge films. High-resolution cross section TEM images, electron energy-loss spectroscopy and energy dispersive X-ray analysis (EDX) data indicate that Ge nanocrystals are present in the amorphous silicon dioxide films. These nanocrystals are formed in two spatially separated layers with average sizes of 15 and 50 nm, respectively. EDX analysis indicates that Ge also diffuses into the Si substrate. PACS 68.73.Lp; 61.46.Hk; 61.46.-w; 68.65.Hb; 61.82.Rx  相似文献   
73.
The design and synthesis of a phthalocyanine – Gd‐DOTA conjugate is presented to open the way to novel molecular theranostics, combining the properties of MRI contrast imaging with photodynamic therapy. The rational design of the conjugate integrates isomeric purity of the phthalocyanine core substitution, suitable biocompatibility with the use of polyoxo water‐solubilizing substituents, and a convergent synthetic strategy ended by the use of click chemistry to graft the Gd‐DOTA moiety to the phthalocyanine. Photophysical and photochemical properties, contrast imaging experiments and preliminary in vitro investigations proved that such a combination is relevant and lead to a new type of potential theranostic agent.  相似文献   
74.
The substituted products alkyl(aryl)thio-tetrahalo-3-nitrobuta-1,3-dienes 3a–b were obtained from the reactions of 1-bromo-1,2,4,4-tetrachloro-3-nitrobuta-1,3-diene (1) with thiols. Further reactions of the substituted product alkyl(aryl)thio-tetrahalo-3-nitrobuta-1,3-dienes 3a–b in dichloromethane reacted with piperazine derivatives and morpholine to generate 5a–b and 7a–l. The structures of the new compounds were determined by microanalysis and spectroscopic data.  相似文献   
75.
76.
Laurel leaf (Laurus nobilis L.) samples that originated from Turkey were analyzed by electron spin resonance (ESR) and thermoluminescence (TL) techniques before and after γ-irradiation. Unirradiated (control) laurel leaf samples exhibit a weak ESR singlet centered at g=2.0020. Besides this central signal were two weak satellite signals situated about 3 mT left and right to it in radiation-induced spectra. The dose–response curve of the radiation-induced ESR signal at g=2.0187 (the left satellite signal) was found to be described well by a power function. Variation of the left satellite ESR signal intensity of irradiated samples at room temperature with time in a long term showed that cellulosic free radicals responsible for the ESR spectrum of laurel leaves were not stable but detectable even after 100 days. Annealing studies at four different temperatures were used to determine the kinetic behavior and activation energy of the radiation-induced cellulosic free radicals responsible from the left satellite signal (g=2.0187) in laurel leaves. TL measurements of the polymineral dust isolated from the laurel leaf samples allowed distinguishing between irradiated and unirradiated samples.  相似文献   
77.
A novel local stereo matching algorithm is introduced to address the fundamental challenge of stereo algorithms, accuracy and computational complexity dilemma. The time consuming intensity dependent aggregation procedure of local methods is improved in terms of both speed and precision. Providing connected 2D support regions, the proposed approach exploits a new paradigm, namely separable successive weighted summation (SWS) among horizontal and vertical directions enabling constant operational complexity. The weights are determined by four-neighborhood intensity similarity of pixels and utilized to model the information transfer rate, permeability, towards the corresponding direction. The same procedure is also utilized to diffuse information through overlapped pixels during occlusion handling after detecting unreliable disparity assignments. Successive weighted summation adaptively cumulates the support data based on local characteristics, enabling disparity maps to preserve object boundaries and depth discontinuities. According to the experimental results on Middlebury stereo benchmark, the proposed method is one of the most effective local stereo algorithm providing high quality disparity models by unifying constant time filtering and weighted aggregation. Hence, the proposed algorithm provides a competitive alternative for various local methods in terms of achieving precise and consistent disparity maps from stereo video within fast execution time.  相似文献   
78.
In pre-equilibrium nuclear reactions, the geometry-dependent hybrid model is applied with the use of the neutron and proton densities to investigate the effect of initial exciton numbers on the nucleon emission spectra. The initial exciton numbers calculated with the theoretical neutron and proton densities have been obtained within the Skryme-Hartree-Fock method with SKM* and SLy4 forces on target nuclei in the 54,56Fe(p, xp) reaction at 61.5-MeV incident proton energy by using a new calculationmethod of Tel et al. Also, the differences between the initial exciton numbers for protons and neutrons as a function of nuclear radius, focusing on systematic discrepancies correlated to differences in the proton and neutron densities have been investigated.  相似文献   
79.
Shafaghi  N.  Kapan  E.  Aydıner  C. C. 《Experimental Mechanics》2020,60(6):735-751
Experimental Mechanics - Inherently tied to the complexity of their deformation mechanisms, Magnesium alloys show a high propensity for strain localization at multiple length-scales. Understanding...  相似文献   
80.
A linear operator T between two lattice-normed spaces is said to be p-compact if, for any p-bounded net xα, the net Txα has a p-convergent subnet. p-Compact operators generalize several known classes of operators such as compact, weakly compact, order weakly compact, AM-compact operators, etc. Similar to M-weakly and L-weakly compact operators, we define p-M-weakly and p-L-weakly compact operators and study some of their properties. We also study up-continuous and up-compact operators between lattice-normed vector lattices.  相似文献   
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