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971.
An integrated procedure based on a direct adaptive control algorithm is applied to structural systems for both vibration suppression and damage detection. The wider class of noncollocated actuator-sensor schemes is investigated through parameterized linear functions of the state variables that preserve the minimum phase property of the system. A larger number of mechanical parameters are shown to be identifiable in noncollocated configurations. Proper output selection allowing for model reference control and tracking error based parameters estimation under persistent excitation is described. Using full-state feedback, these capabilities are effectively exploited for oscillation reduction and health monitoring of uncertain multi-degree-of-freedom (MDOF) shear-type structures. 相似文献
972.
Francesco Caponio Vincenzo Alloggio Cosimo Pallavicini 《European Journal of Lipid Science and Technology》1998,100(3):74-78
The lipid fraction of goat milk was subjected to transesterification using a commercially available immobilized lipase to decrease the amount of short- and medium-chain fatty acids (C4–C14) by enrichment of the reaction mixture with long-chain (C18:1 and C18:2) fatty acids. Aliquots were taken during, transesterification at different reaction times and analyzed for triglycerides and their fatty acid components. The gas chromatographic analyses of triglycerides (previously isolated by thinlayer chromatography) showed that at 6 h reaction under the experimental conditions led to the greatest reduction of the low molecular weight triglycerides (C22–C38) and concomitantly to the greatest increase in the higher molecular weight triglycerides (C48–C54). These changes correlated with the variations observed in the fatty acids of the triglyceride fraction. 相似文献
973.
974.
Elena Chugunova Nurgali Akylbekov Alexey Dobrynin Alexander Burilov Carla Boga Gabriele Micheletti Vincenzo Frenna Edoardo Jun Mattioli Matteo Calvaresi Domenico Spinelli 《International journal of molecular sciences》2021,22(24)
This research focuses on the X-ray structure of 4,6-dichloro-5-nitrobenzofuroxan 1 and of some of its amino derivatives (4a, 4e, 4g, and 4l) and on DFT calculations concerning the nucleophilic reactivity of 1. We have found that by changing the solvent used for crystallization, it is possible to obtain 4,6-dichloro-5-nitrobenzofuroxan (1) in different polymorphic structures. Moreover, the different torsional angles observed for the nitro group in 1 and in its amino derivatives (4a, 4e, 4g, and 4l) are strictly dependent on the steric hindrance of the substituent at C-4. DFT calculations on the course of the nucleophilic substitution confirm the role of the condensed furoxan ring in altering the aromaticity of the carbocyclic frame, while chlorine atoms strongly influence the dihedral angle and the rotational barrier of the nitro group. These results corroborate previous observations based on experimental kinetic data and give a deep picture of the reaction with amines, which proceeds via a “non-aromatic” nucleophilic substitution. 相似文献
975.
Chiara Camponeschi Maria De Carluccio Susanna Amadio Maria Elisabetta Clementi Beatrice Sampaolese Cinzia Volont Maria Tredicine Vincenzo Romano Spica Rosa Di Liddo Francesco Ria Fabrizio Michetti Gabriele Di Sante 《International journal of molecular sciences》2021,22(24)
S100B is an astrocytic protein behaving at high concentration as a damage-associated molecular pattern molecule. A direct correlation between the increased amount of S100B and inflammatory processes has been demonstrated, and in particular, the inhibitor of S100B activity pentamidine has been shown to ameliorate clinical scores and neuropathologic-biomolecular parameters in the relapsing-remitting experimental autoimmune encephalomyelitis mouse model of multiple sclerosis. This study investigates the effect of arundic acid (AA), a known inhibitor of astrocytic S100B synthesis, in the chronic experimental autoimmune encephalomyelitis, which is another mouse model of multiple sclerosis usually studied. By the daily evaluation of clinical scores and neuropathologic-molecular analysis performed in the spinal cord, we observed that the AA-treated group showed lower severity compared to the vehicle-treated mice, particularly in the early phase of disease onset. We also observed a significant reduction of astrocytosis, demyelination, immune infiltrates, proinflammatory cytokines expression and enzymatic oxidative reactivity in the AA-treated group. Overall, our results reinforce the involvement of S100B in the development of animal models of multiple sclerosis and propose AA targeting the S100B protein as a focused potential drug to be considered for multiple sclerosis treatment. 相似文献
976.
977.
A fast, reliable and precise method for the determination of Ba, Zr, Th, U, La, Ce, Eu, Hf and Gd in leaching solutions containing up to 1 mol/L FeCl3 by inductively coupled plasma-atomic emission spectrometry (ICP-AES) was described. Liquid-liquid extraction with diethyl ether was applied for selective and quantitative extraction of the iron with a decontamination factor of 65000. The study has enabled the determination of rare earth elements, U, Th Ba, and Zr, from the solution with high iron content with detection limits in the range of 1-24 ng/ml and a precision of 0.9%-4.6 % relative standard deviation. The developed method was simple and was adopted for implementation in a glove box for handling radioactive materials. 相似文献
978.
Antonella De Leonardis Vincenzo Macciola 《European Journal of Lipid Science and Technology》2002,104(3):156-160
In this work the Rancimat technique (temperature 110 °C and air flow 20 l/h) was used in order to test the catalytic effect induced by Cu(II)‐and Fe(III)‐ions on olive oil oxidation. Different amounts of Cu(II)‐ and Fe(III)‐cyclohexanebutyrates were added to a refined olive oil. Copper was shown to be a more active catalyst than iron. In fact, the induction time of the oil was halved by the addition of about 120 ng/g of copper versus 9000 ng/g of iron. The effect of copper and iron was also evaluated on the oil enriched with increasing quantities of caffeic acid (50, 100 and 200 mg/kg). The addition of this phenol induced a significant protective effect which delayed the oxidation of both the control and the oil samples enriched with metals. However, copper‐catalyzed oxidation also in the presence of the antioxidant, thus decreasing the oil oxidative stability approximately three times compared to the control. 相似文献
979.
Pter Sere Nikolett Zsigri Timea Raffai Szabina Furdan Fanni Gyri Vincenzo Crunelli Magor L. Lrincz 《International journal of molecular sciences》2021,22(17)
(1) Background: Absence seizures (ASs) are sudden, transient lapses of consciousness associated with lack of voluntary movements and generalized 2.5–4 Hz spike-wave discharges (SWDs) in the EEG. In addition to the thalamocortical system, where these pathological oscillations are generated, multiple neuronal circuits have been involved in their modulation and associated comorbidities including the serotonergic system. Neuronal activity in one of the major synaptic input structures to the brainstem dorsal raphé nucleus (DRN), the lateral hypothalamus (LH), has not been characterized. (2) Methods: We used viral tract tracing and optogenetics combined with in vitro and in vivo electrophysiology to assess the involvement of the LH in absence epilepsy in a genetic rodent model. (3) Results: We found that a substantial fraction of LH neurons project to the DRN of which a minority is GABAergic. The LH to DRN projection can lead to monosynaptic iGluR mediated excitation in DRN 5-HT neurons. Neuronal activity in the LH is coupled to SWDs. (4) Conclusions: Our results indicate that a brain area involved in the regulation of autonomic functions and heavily innervating the RN is involved in ASs. The decreased activity of LH neurons during SWDs could lead to both a decreased excitation and disinhibition in the DRN. These results support a long-range subcortical regulation of serotonergic neuromodulation during ASs and further our understanding of the state-dependence of these seizures and some of their associated comorbidities. 相似文献
980.
Realizing and installing renewable energy plants have an environmental “footprint” that has to be evaluated to quantify the real impact of renewable technologies on the environment. Nowadays, the most important tool to evaluate this impact of a product is the Life Cycle Assessment (LCA).The aim of this work is to present a Life Cycle Assessment of an innovative solar technology, the molten salt concentrating solar power (CSP) plant combined with a biomass Back-Up Burner, developed by Italian Research Centre ENEA and able to produce clean electricity by using solar energy. The Life Cycle Assessment was carried out by means of the SimaPro7 software, one of the most used LCA software in the world.In the second part of the study the environmental performance of the CSP plant was compared with these of conventional oil and gas power plants. 相似文献