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61.
Nuclear quantum dynamics beyond the Born-Oppenheimer approximation is performed using quantum trajectories. Withintheadiabaticrepresentationoftheelectronicstates, NABDY(NonAdiabaticBohmianDYnamics) is used in combination with DFT and LR-TDDFT to perform on-the-fly nonadiabatic quantum dynamics. Simple numerical test systems and current limitations of the method are discussed.  相似文献   
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This work aimed the incorporation of the enzyme bromelain from pineapple peel into dermatological bases for potential therapeutic application. The enzyme was incorporated into Lanette cream and lotion, as well as Carbopol gel and Chemyunion cream and lotion, at a concentration of 0.5% (w/w). These bases were subjected to centrifugation test and accelerated stability test during 90 days at 25 ℃(with and without sunlight), 37 ℃ and 4 ℃, in order to evaluate bromelain stability in dermatological bases. Total protein content and enzymatic activity were measured. The bases were stable as its organoleptic characteristics (appearance, color, smell and sensitivity to touch) only when kept at 4 ℃ with activity remaining 95.5%, 84,9%. 77.7%, 73.8% and 72.3%, alter 90 days of testing in Carbopol gel, Lanette and Chemyunion cream, and Lanette and Chemyunion lotion, respectively. Based on the results, it was possible to incorporate bromelain into dermatological bases, and the activity was well preserved when these bases were kept in refrigerator at 4 ℃.  相似文献   
64.
The deactivation of a nickel reforming catalyst during the upgrading of the producer gas obtained by gasification of lignocellulosic biomass was studied. The research involved several steps: the selective deactivation of the catalyst in a laboratory scale; the streaming of the catalyst with the producer gas of a downdraft and an oxygen/steam circulating fluidized bed (CFB) gasifier; and tests in a reformer placed in a slipstream of the CFB gasifier. The information obtained allowed to elucidate the catalyst deactivation mechanisms taking place during the reforming of the producer gas: physical deactivation by deposition of fine ashes, aerosol particulate or carbon; poisoning by H2S and HCl present in the gas phase and thermal sintering because of the high operation temperatures required to avoid the chemical deactivation. These physical and chemical effects depended on the composition of the biomass fuel.  相似文献   
65.
Agomelatine is a naphthalenic analogue of melatonin that is in clinical use for the treatment of major depressive disorders. Interestingly, while agomelatine exhibits potent affinity for melatonin receptors, it binds with only moderate affinity to the serotonin 5‐HT2C receptor. Optimization of agomelatine toward this target could further potentiate its clinical efficacy. To explore this hypothesis and to access derivatives in which a key point of agomelatine metabolism is blocked, a series of naphthalenic derivatives was designed and synthesized as novel analogues of agomelatine. Most of the prepared compounds exhibited good binding affinity at the melatonin MT1 and MT2 receptor subtypes. Two compounds, an acetamide and an acrylamide derivative, exhibited good binding affinities at both the human melatonin (MT) receptors and the serotonin 5‐HT2C receptor subtype, with pKi values of 7.96 and 7.95 against MT1, 7.86 and 8.68 against MT2, and 6.64 and 6.44 against 5‐HT2C, respectively.  相似文献   
66.
The ethanol steam reforming reaction carried out in a Pd-based tubular membrane reactor has been modelled via a finite element code. The model considers the membrane tube divided into finite volume elements where the mass balances for both lumen and shell sides are carried out accordingly to the reaction and permeation kinetics. Especially, a simplified “power law” has been applied for the reaction kinetics: the comparison with experimental data obtained by using three different kinds of catalyst (Ru, Pt and Ni based) permitted defining the coefficients of the kinetics expression as well as to validate the model. Based on the Damkohler–Peclet analysis, the optimization of the membrane reformer has been also approached.  相似文献   
67.

The prediction of the average size of fragments in blasted rock piles produced after blasting in aggregate quarries is essential for decresing the cost of crushing and secondary breaking. There are several conventional and advanced processes to estimate the size of blasted rocks. Among these, the empirical prediction of the expected fragmentation in most cases is carried out by Kuznetsov’s equation (Sov Min Sci 9:144–148, 1973), modified by Lilly (1986) and Cunningham (1987). The present research focuses on the effect of the engineering geological factors and blasting process on the blasted fragments using a more powerful, advanced computational tool, an artificial neural network. In particular, the blast database consists of the blastability index of limestone on the pit face, the quantities of the explosives and of the blasted rock pile, assessing the interaction of these parameters on the blasted rocks. The data were collected from two aggregate quarries, Drymos and Tagarades, near Thessaloniki, in the Central Macedonia region of Greece. This approach indicates significant performance stability, providing the fragmentation size with high accuracy.

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A new Magnetic Ion EXchange resin for DOC (Dissolved Organic Carbon) removal (MIEX DOC Resin) has been evaluated as water pre-treatment at the Drinking Water Treatment Plant (DWTP) of Florence in order to reduce the oxidant demand and disinfection by-products (DBPs) formation potential. This pre-treatment leads to several effects on downstream treatment processes. In this experimental study the effects of MIEX pre-treatment on clariflocculation process were evaluated with respect to coagulant demand reduction and characteristics of flocs formed. The analysis was conducted using traditional jar test procedures and a Photometric Dispersion Analyser (PDA2000) which provided continuous information about the aggregation state of particles during the jar tests.For a fixed turbidity goal in clarified water, ion exchange pre-treatment led to coagulant dosage reduction up to 60% and PDA results shown that flocs formed in pre-treated water were bigger and more resistant to shearing effects than those formed by conventional clariflocculation.  相似文献   
70.
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