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排序方式: 共有249条查询结果,搜索用时 869 毫秒
131.
Leulescu Marian Rotaru Andrei Moanţă Anca Iacobescu Gabriela Pălărie Ion Cioateră Nicoleta Popescu Mariana Criveanu Marius Cătălin Morîntale Emilian Bojan Mihaela Rotaru Petre 《Journal of Thermal Analysis and Calorimetry》2021,143(6):3945-3967
Journal of Thermal Analysis and Calorimetry - Azorubine (E122), an azoic dye with the chemical formula C20H12N2Na2O7S2, has a wide range of applications in the food and cosmetic industries.... 相似文献
132.
Servilia Oancea Florin Grosu Anca Lazar Ioan Grosu 《Chaos, solitons, and fractals》2009,41(5):2575-2580
A single controller for synchronization of two Lorenz systems is obtained by using Lyapunov function. Numerical results are given for the all three cases with one controller in each equation. Controller contains two or three variables of the master system. 相似文献
133.
Anca Grad 《Journal of Mathematical Analysis and Applications》2010,361(1):86-95
In this article we provide weak sufficient strong duality conditions for a convex optimization problem with cone and affine constraints, stated in infinite dimensional spaces, and its Lagrange dual problem. Our results are given by using the notions of quasi-relative interior and quasi-interior for convex sets. The main strong duality theorem is accompanied by several stronger, yet easier to verify in practice, versions of it. As exemplification we treat a problem which is inspired from network equilibrium. Our results come as corrections and improvements to Daniele and Giuffré (2007) [9]. 相似文献
134.
The synthesis of multi-walled carbon nanotubes (MWNTs) by catalytic pyrolysis of the phenol-formaldehyde resins 总被引:1,自引:0,他引:1
Ioan Stamatin Adina Morozan Anca Dumitru V. Ciupina G. Prodan J. Niewolski H. Figiel 《Physica E: Low-dimensional Systems and Nanostructures》2007,37(1-2):44
A series of carbon nanomaterials, particularly multi-walled carbon nanotubes (MWNT), are obtained as products from catalytic pyrolysis of the cross-linked phenol-formaldehyde resins with different ferrocene under inert atmosphere. The morphology and structure of the samples were evaluated by TEM and XRD techniques. CNTs morphology is dependent on the iron nanoparticles and their forms (Fe, Fe3C) resulted from ferrocene decomposition. The amount of nanotubes increases with iron content released from ferrocene catalyst during the pyrolysis process. Fe3C nanoparticles drive the nucleation and the growth of carbon nanotubes during the pyrolysis process. Long (up to microns) well-defined MWNTs with small defects, ropes and disordered carbon are representatives in the pyrolyzed resins composition. 相似文献
135.
A. T. Grecu D. Grecu Anca Visinescu 《International Journal of Theoretical Physics》2007,46(5):1190-1204
The modulational instability (MI) in the class of NLS equations is discussed using a statistical approach (SAMI). A kinetic
equation for the two-point correlation function is studied in a linear approximation, and an integral stability equation is
found. The modulational instability is associated with a positive imaginary part of the frequency. The integral equation is
solved for different types of initial distributions (δ-function, Lorentzian) and the results are compared with those obtained
using a deterministic approach (DAMI). The differences between MI of the normal NLS equation and derivative NLS equations
is emphasized.
PACS: 05.45. 相似文献
136.
137.
Pop A Vysotsky MO Saadioui M Böhmer V 《Chemical communications (Cambridge, England)》2003,(10):1124-1125
The possibilities to form dimeric capsules with supramolecular chirality from tetraurea calix[4]arenes composed of two different phenolic urea units are discussed in general and demonstrated experimentally for various selected examples. 相似文献
138.
Ioana Corina Bocsan Raluca Maria Pop Octavia Sabin Elias Sarkandy Paul-Mihai Boarescu tefan Horia Roian Poliana Mihaela Leru Veronica Sanda Chedea Sonia Ancua Socaci Anca Dana Buzoianu 《Molecules (Basel, Switzerland)》2021,26(11)
The study’s aim was to characterize the composition of Nigella sativa seed (NSO) and grape seed (GSO) oils, and to evaluate their cardioprotective and anti-inflammatory effect on isoproterenol (ISO)-induced ischemia in rats. Materials and Methods: NSO and GSO supplements were physicochemically characterized. Liquid chromatography–mass spectrometry (HPLC-MS), Fourier-transform infrared spectroscopy (FTIR), and gas chromatography–mass spectrometry (GC-MS) analyses were used to determine the phytochemical composition in the oils. Total polyphenol content (TPC) and in vitro antioxidant activity were also determined. Pretreatment with 4 mL/kg/day NSO or GSO was administered to rats for 14 days. The experimental ischemia was induced by a single administration of ISO 45 mg/kg after 14 days. An electrocardiogram (ECG) was performed initially and 24 h after ISO. Biological evaluation was done at the end of experiment. Results: The HPLC-MS, GC-MS, and FTIR analyses showed that both NSO and GSO are important sources of bioactive compounds, especially catechin and phenolic acids in GSO, while NSO was enriched in flavonoids and thymol derivatives. Pretreatment with GSO and NSO significantly reduced ventricular conduction, prevented the cardiotoxic effect of ISO in ventricular myocardium, and reduced the level of proinflammatory cytokines and CK-Mb. Conclusion: Both NSO and GSO were shown to have an anti-inflammatory and cardioprotective effect in ISO-induced ischemia. 相似文献
139.
Direct observation of protein motion during the photochemical reaction cycle of bacteriorhodopsin 总被引:1,自引:0,他引:1
Bálint Z Végh GA Popescu A Dima M Ganea C Varó G 《Langmuir : the ACS journal of surfaces and colloids》2007,23(13):7225-7228
Platinum-coated, conductive atomic force microscope cantilevers were used to deposit electrophoretically purple membranes from Halobacterium salinarum on the bottom part of the cantilevers. By illuminating the bacteriorhodopsin-containing purple membranes, the protein goes through its photochemical reaction cycle, during which a conformational change happens in the protein, changing its shape and size. The size change of the protein acts upon the cantilever by causing its deflection, which can be monitored by the detection system of the atomic force microscope. The shape of the signal, the action spectrum of the deflection amplitude, and the blue light inhibition of the deflection all prove that the origin of the signal is the conformational change arising in the bacteriorhodopsin during the photocycle. From the size of the signal, the magnitude of the protein motion could be estimated. Using polarized light, the orientation of the motion was determined, relative to the transition moment of the retinal. 相似文献
140.
Galyna Volynets Hanna Vyshniakova Georgiana Nitulescu George Mihai Nitulescu Anca Ungurianu Denisa Margina Olena Moshynets Volodymyr Bdzhola Ihor Koleiev Olga Iungin Sergiy Tarnavskiy Sergiy Yarmoluk 《Molecules (Basel, Switzerland)》2021,26(23)
Staphylococcus aureus (S. aureus) is a causative agent of many hospital- and community-acquired infections with the tendency to develop resistance to all known antibiotics. Therefore, the development of novel antistaphylococcal agents is of urgent need. Sortase A is considered a promising molecular target for the development of antistaphylococcal agents. The main aim of this study was to identify novel sortase A inhibitors. In order to find novel antistaphylococcal agents, we performed phenotypic screening of a library containing 15512 compounds against S. aureus ATCC43300. The molecular docking of hits was performed using the DOCK program and 10 compounds were selected for in vitro enzymatic activity inhibition assay. Two inhibitors were identified, N,N-diethyl-N′-(5-nitro-2-(quinazolin-2-yl)phenyl)propane-1,3-diamine (1) and acridin-9-yl-(1H-benzoimidazol-5-yl)-amine (2), which decrease sortase A activity with IC50 values of 160.3 µM and 207.01 µM, respectively. It was found that compounds 1 and 2 possess antibacterial activity toward 29 tested multidrug resistant S. aureus strains with MIC values ranging from 78.12 to 312.5 mg/L. These compounds can be used for further structural optimization and biological research. 相似文献