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131.
Soumaya Nasri Mouhieddinne Guergueb Jihed Brahmi Youssef O. Al-Ghamdi Florian Molton Frdrique Loiseau Ilona Turowska-Tyrk Habib Nasri 《Molecules (Basel, Switzerland)》2022,27(24)
The present work describes the preparation and characterization of a new cobalt(III) porphyrin coordination compound named (chlorido)(nicotinoylchloride)[meso-tetra(para-chlorophenyl)porphyrinato]cobalt(III) dichloromethane monosolvate with the formula [CoIII(TClPP)Cl(NTC)]·CH2Cl2 (4). The single-crystal X-ray molecular structure of 4 shows very important ruffling and waving distortions of the porphyrin macrocycle. The Soret and Q absorption bands of 4 are very red-shifted as a consequence of the very distorted porphyrin core. This coordination compound was also studied by fluorescence and cyclic voltammetry. The efficiency of our four porphyrinic compounds—the H2TClPP (1) free-base porphyrin, the [CoII(TClPP)] (2) and [CoIII(TClPP)Cl] (3) starting materials, and the new Co(III) metalloporphyrin [CoIII(TClPP)Cl(NTC)]·CH2Cl2 (4)—as catalysts in the photochemical degradation was tested on malachite green (MG) dye. The current voltage of complexes 3 and 4 was also studied. Electrical parameters, including the saturation current density (Js) and barrier height (ϕb), were measured. 相似文献
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Optical Review - Both Fabry–Pérot interferometry and the DC electrochemical method have been simultaneously used for the first time to measure in situ the anodic current density (J) of... 相似文献
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Pardes Habib Jennifer Jung Gina Maria Wilms Alma Kokott-Vuong Shahin Habib Jrg B. Schulz Aaron Voigt 《Experimental & molecular medicine》2021,53(2):264
Hypoxia is an underlying pathophysiological condition of a variety of devastating diseases, including acute ischemic stroke (AIS). We are faced with limited therapeutic options for AIS patients, and even after successful restoration of cerebral blood flow, the poststroke mortality is still high. More basic research is needed to explain mortality after reperfusion and to develop adjunct neuroprotective therapies. Drosophila melanogaster (D.m.) is a suitable model to analyze hypoxia; however, little is known about the impacts of hypoxia and especially of the subsequent reperfusion injury on the behavior and survival of D.m. To address this knowledge gap, we subjected two wild-type D.m. strains (Canton-S and Oregon-R) to severe hypoxia (<0.3% O2) under standardized environmental conditions in a well-constructed hypoxia chamber. During posthypoxic reperfusion (21% O2), we assessed fly activity (evoked and spontaneous) and analyzed molecular characteristics (oxidative stress marker abundance, reactive oxygen species (ROS) production, and metabolic activity) at various timepoints during reperfusion. First, we established standard conditions to induce hypoxia in D.m. to guarantee stable and reproducible experiments. Exposure to severe hypoxia under defined conditions impaired the climbing ability and reduced the overall activity of both D.m. strains. Furthermore, a majority of the flies died during the early reperfusion phase (up to 24 h). Interestingly, the flies that died early exhibited elevated activity before death compared to that of the flies that survived the entire reperfusion period. Additionally, we detected increases in ROS and stress marker (Catalase, Superoxide Dismutase and Heat Shock Protein 70) levels as well as reductions in metabolic activity in the reperfusion phase. Finally, we found that changes in environmental conditions impacted the mortality rate. In particular, decreasing the temperature during hypoxia or the reperfusion phase displayed a protective effect. In conclusion, our data suggest that reperfusion-dependent death might be associated with elevated temperatures, predeath activity, and oxidative stress.Subject terms: Stroke, Molecular neuroscience 相似文献
136.
Habib Firouzabadi Nasser Iranpoor Farhad NowrouziKamal Amani 《Tetrahedron letters》2003,44(20):3951-3954
An efficient and chemoselective preparation of acylals from structurally different aldehydes in the presence of AlPW12O40 and acetic anhydride was achieved easily in high yields at room temperature under solvent-free conditions. 相似文献
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The bump number b(P) of a partial order P is the minimum number of comparable adjacent pairs in some linear extension of P. It has an interesting application in the context of linear circuit layout problems. Its determination is equivalent to maximizing the number of jumps in some linear extension of P, for which the corresponding minimization problem (the jump number problem) is known to be NP-hard. We derive a polynomial algorithm for determining b(P). The proof of its correctness is based on a min-max theorem involving simple-structured series-parallel partial orders contained in P. This approach also leads to a characterization of all minimal partial orders (with respect to inclusion of the order relations) with fixed bump number.Supported by Sonderforschungsbereich 303 of the University of Bonn.Supported by DAAD and SSHRC, Grant No. 451861295. 相似文献
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Habib Ammari 《Journal of Mathematical Analysis and Applications》2003,282(2):479-494
We consider the inverse problem of reconstructing small amplitude perturbations in the conductivity for the wave equation from partial (on part of the boundary) dynamic boundary measurements. Through construction of appropriate test functions by a geometrical control method we provide a rigorous derivation of the inverse Fourier transform of the perturbations in the conductivity as the leading order of an appropriate averaging of the partial dynamic boundary perturbations. This asymptotic formula is generalized to the full time-dependent Maxwell's equations. Our formulae may be expected to lead to very effective computational identification algorithms, aimed at determining electromagnetic parameters of an object based on partial dynamic boundary measurements. 相似文献
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Habib Firouzabadi Nasser Iranpoor Abbas Ali Jafari Somayeh Makarem 《Journal of molecular catalysis. A, Chemical》2006,250(1-2):237-242
AlPW12O40 as a recyclable Lewis acid and stable solid compound was introduced for efficient ring opening of different epoxides with thiols, acetic acid, and primary, secondary, and tertiary alcohols. These processes were carried out at room temperature with high regio- and stereoselectivity. 相似文献