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991.
Roberto Vitturi Bruno Zava Maria Stella Colomba Alessandro Pellerito Francesco Maggio Lorenzo Pellerito 《应用有机金属化学》1995,9(7):561-566
In Order to test in vivo cytotoxicity of diorganotin(IV)-amoxicillin (amox) derivatives, mitotic chromosomes of Rutilus rubilio (Pisces, Cyprinidae) have been analyzed using two different chromosome-staining techniques. Results gathered after exposure of fish to the free amox · 3H2O, R2SnClamox · 2H2O, and R2Snamox · 2 2H2O (R = methyl, butyl and phenyl; amox− = 6-[D(−)-β-amino-p-hydroxyphenylacetamido]penicillinate) suggest that methyl derivatives seem to exert a lower cytotoxicity than butyl and phenyl ones and that R2Snamox · 2 2H2O deriva-tives are more toxic than R2SnClamox · 2H2O at both 10−5 and 10−7mol dm−3 concentrations. The following structural lesions have been iden-tified by comparative analysis of mitotic chromo-somes from untreated specimens (controls) and specimens treated with diorganotin(IV)-amoxicillin derivatives: (1) differentially stained chromosome areas; (2) granular deeply stained zones along the chromosomal body; (3) arm breakages; and (4) side-arm bridges (pseudochiasmata). 相似文献
992.
Stella Lorenzo Smyth Jonathan Dromey Brendan Kohanoff Jorge 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2021,75(7):1-9
The European Physical Journal D - We discuss a Faddeev-like iterative approach which allows one to consistently include the Coulomb potential in strong field phenomena through a Born series. To... 相似文献
993.
Lorenzo Marrucci 《Liquid Crystals Today》2013,22(3):6-33
Abstract After twenty years the ILCC this year returned to its birth place in Kent State University. In comparison with the last time the ILCC visited Kent, it was much larger and at this year's conference nearly 750 participants from 40 countries contributed over 900 papers during the week. The conference was organized by Professors 5. Kumar (chairman), 1. West (vice-chairman), D. Finotello (secretary), and J. Fulghum (treasurer), while Professor William Doane, retiring director of the liquid Crystal Institute at Kent State, served as honorary chairman. 相似文献
994.
D. Rideau P. Monceau H. Requardt R. Currat F. Nad J. E. Lorenzo S. Brazovskii N. Kirova D. Smilgies G. Grü bel 《Physica B: Condensed Matter》2000,280(1-4):317-322
Phase slippage is required at the current electrodes of quasi-one-dimensional conductors with a charge density wave (CDW) ground state for the conversion from free to condensed carriers. We have performed at the ESRF high-resolution X-ray measurements of the spatially varying shift q(x) of the CDW satellite wave vector between current contacts on a thin NbSe3 whisker in the sliding state. Applying direct currents, we observe at 90 K a steep exponential decrease of the shift within a few hundred microns from the contact. The CDW strain profile q(x) reflects the carrier conversion process, via nucleation and growth of phase-dislocation loops. Pulsed current measurements of the shift q show important differences between pulsed and dc current data, revealing a spatially dependent relaxational behaviour of the CDW strain. Using time-resolved high spatial resolution X-ray we observe at 300 μm from the electrode a stretched exponential-type decay of the shift q(t) upon switching off the current (T=75 K): q(t)=q0[exp(−t/τ)μ] with τ=23 ms and μ=0.36. 相似文献
995.
E. Vázquez Blanco P. López Mahía S. Muniategui Lorenzo D. Prada Rodríguez E. Fernández Fernández 《Analytical and bioanalytical chemistry》2000,366(3):283-288
Microwave energy was applied to extract polycyclic aromatic hydrocarbons (PAHs) and linear aliphatic hydrocarbons (LAHs) from marine sediments. The influence of experimental conditions, such as different extracting solvents and mixtures, microwave power, irradiation time and number of samples extracted per run has been tested using real marine sediment samples; volume of the solvent, sample quantity and matrix effects were also evaluated. The yield of extracted compounds obtained by microwave irradiation was compared with that obtained using the traditional Soxhlet extraction. The best results were achieved with a mixture of acetone and hexane ¶(1?:?1), and recoveries ranged from 92 to 106%. The extraction time is dependent on the irradiation power and the number of samples extracted per run, so when the irradiation power was set to 500 W, the extraction times varied from 6 min for 1 sample to 18 min for 8 samples. Analytical determinations were carried out by high-performance liquid chromatography (HPLC) with an ultraviolet-visible photodiode-array detector for PAHs and gas chromatography (GC) using a FID detector for LAHs. To test the accuracy of the microwave-assisted extraction (MAE) technique, optimized methodology was applied to the analysis of standard reference material (SRM 1941), obtaining acceptable results. 相似文献
996.
Pedro Gili Pedro Núez Pedro Martín‐Zarza Pablo A. Lorenzo‐Luis 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e441-e442
The title compound, (C3H5N2)4[β‐Mo8O26], has been prepared from imidazole octamolybdate, (C3H5N2)4[(C3H4N2)2(γ‐Mo8O26)], which was described previously. The γ→β conversion is produced in the presence of Cu(NO3)2·3H2O and is reported for the first time in this work. The X‐ray structure analysis confirmed the presence of the [Mo8O26]4? anion. The structure consists of β‐Mo8O26 polyanions and imidazolium cations. These cations are linked to the terminal and bridging O atoms of the anion by hydrogen bonds. 相似文献
997.
The aim of the study was to evaluate the effects of Salvia hispanica and Nigella sativa seed addition on the volatile compounds and sensory characteristics (with particular emphasis on odor and flavor) of traditionally produced dry fermented sausages with reduced nitrites. Five different sausage formulations were prepared: control sample; samples with 1% and 2% addition of chia seed; samples with 1% and 2% addition of black cumin seed. The sausages were subjected to analysis including proximate chemical composition, volatile compound determination, and sensory analysis. The sausages with chia seed in the amounts of 1% and 2% as well as the sample with 1% addition of black cumin seed were characterized by positive sensory features, and their overall quality was rated above 7 c.u. on a 10-point scale, similar to the control sausage. Sausage samples with the addition of cumin seed were characterized by the highest herbal odor and flavor. The addition of Salvia hispanica and Nigella sativa seed significantly affected the amount of volatile compounds in fermented sausages. Sausages with black cumin presented the greatest amount of total volatile compounds, mainly contributed by terpenes. 相似文献
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