A knowledge-based expert system for dyeing of cotton. Part 2: Testing and evaluation

The diagnosis of a number of faulty dyed samples and faults obtained from case studies was carried out by both human experts and the expert system developed in this study, and their performance was compared. An evaluation copy of the software was provided to a number of potential users to obtain feedback on the utility and the helpfulness of the system. The results show highly satisfactory performance when compared to human experts as well as considerable utility potential, providing further impetus for further improvements in the system.     

High prevalence of hepatitis C virus infection in patients with non-Hodgkin''s lymphoma at the onset. Preliminary results of an Italian multicenter study]

Inhibitors of carbonic anhydrase activity have been found to increase blood and organ PCO2 and to increase blood flow (BF) in individual organs. To determine whether carbonic anhydrase inhibition coordinately induces an increase in BF in several organs, we assayed the effect of the carbonic anhydrase inhibitor, acetazolamide (AZ), on BF in rabbit organs using the colored microsphere (CM) assay. Eight female white rabbits were anesthetized with ketamine and urethane, and administered three sequential doses of 4 mg/kg AZ. After each dose, the rabbits were injected with 9 x 10(5) CMs of different colors, and arterial blood was collected. We found that AZ had no effect on blood pressure, body temperature, hemoglobin concentration, or PaCO2. In contrast, 12 mg/kg AZ significantly increased PaO2 and significantly decreased base excess. When we measured organ BF, we observed, in response to 12 mg/kg AZ, an 82% increase in brain BF and a 55% increase in kidney BF, but no change in BF of the liver, stomach wall, or abdominal muscle. These findings suggest that the inhibition of carbonic anhydrase activity by AZ, which decreases the rate of CO2 conversion to HCO3-, causes the retention of CO2 in tissues and organs, and thus increases BF in specific organs. Administration of carbonic anhydrase inhibitors, such as AZ, may increase BF to the brain and kidney without reducing PaO2, thereby increasing the supply of oxygen in conditions involving hypoxia such as ischemia and shock.     

Dyeing characteristics of a Tencel alloy fibre

The exceptional characteristics of Tencel have been modified by incorporating poly(ethylene terephthalate) during solvent spinning, giving the novel Tencel alloy. The present work involved studying the dyeing characteristics of Tencel and Tencel alloy using a range of multifunctional reactive dyes. The fibrillation properties of the fibres was also investigated. Scanning electron microscope studies were carried out to observe the degree of fibrillation of these fibres after wet treatment. Optical microscopy was also carried out to confirm the absence of ring dyeing in fibres dyed using the padding technique.     

Ray propagation in nonuniform random lattices. Part II

In this paper and its companion [J. Opt. Soc. Am. A.23, 2251 (2006)], the problem of ray propagation in nonuniform random half-plane lattices is considered. Cells can be independently occupied according to a density profile that depends on the lattice depth. An electromagnetic source external to the lattice radiates a monochromatic plane wave that undergoes specular reflections on the occupied sites. The probability of penetrating up to level k inside the lattice is analytically evaluated using two different approaches, the former applying the theory of Markov chains (Markov approach) and the latter using the theory of Martingale random processes (Martingale approach). The full theory concerned with the Martingale approach is presented here, along with an innovative modification that leads to some improved results. Numerical validation shows that it outperforms the Markov approach when dealing with ray propagation in dense lattices described by a slowly varying density profile.     

Identification of cocaine and its metabolites in urban wastewater and comparison with the human excretion profile in urine

The most relevant human urinary metabolites of cocaine (nine metabolites) were measured in urban wastewater in Italy and USA. A novel analytical method based on liquid chromatography tandem mass spectrometry allowed the identification of ecgonine, ecgonine methyl ester and the pyrolytic derivatives of cocaine in untreated wastewater. The aim of this study was to verify whether the pattern of cocaine metabolites in wastewater reflected the human excretion profile in urine. The performance of the method was good, with recoveries higher than 60% and limits of quantifications in the low ng/L range. The stability in untreated wastewater was assessed for all metabolites and the best storage condition resulted freezing samples immediately after collection and keep them frozen until analysis. All the selected compounds were measured in wastewater at concentrations up to 1.5 μg/L and their weekly loads were calculated during a five weeks monitoring campaign in Milan (Italy). The profiles of cocaine metabolites in wastewater matched with those in human urine reported in the literature, suggesting that measures in wastewater reflect the real human excretion and that wastewater analysis is suitable for assessing drug consumption. Benzoylecgonine was confirmed as the best target for estimating cocaine use by wastewater analysis, while cocaine itself should not be considered because its amount in wastewater is affected by other environmental sources such as transport, handling and consumption. Results suggested that the measurement of other metabolites in combination with benzoylecgonine might reflect 60% of an administered dose of cocaine providing also information on different patterns of use.     

1H low- and high-field NMR study of the effects of plasma treatment on the oil and water fractions in crude heavy oil

The chemical and physical properties of a Brazilian heavy oil submitted to plasma treatment were investigated by ¹H low- and high-field nuclear magnetic resonance (NMR) combined to the characterization of rheological properties, thermogravimetry and measurement of basic sediments and water (BSW) content. The crude oil was treated in a dielectric barrier discharge plasma reactor, using natural gas, CO₂ or H₂ as working gas. The results indicated a large drop in the water content of the plasma-treated samples as compared to the crude oil, giving rise to a reduction in the viscosity. No significant chemical change was produced in the oil portion itself, as observed by ¹H NMR. The water contents determined by ¹H low-field NMR analyses agreed well with those obtained by BSW, indicating the low-field NMR methods as a useful tool for following the effects of plasma treatments on heavy oils, allowing the separation of the effects caused on the water and oil fractions.     

Photodegradation of copolyester films: A mechanistic study

The photodegradation of copolyesters based on 1,4-cyclohexanedimethanol (CHDM), tetramethyl-1,3-cyclobutanediol, and terephthalic acid units was investigated using various analytical methods. Photodegradation products were characterized using Fourier transform infrared (FTIR), liquid chromatography–mass spectrometry (LC–MS), and X-ray Photoelectron spectroscopy (XPS) analysis. The homolytic scission of C-O bonds of ester groups through a Norrish Type I reaction was supported by time of flight secondary ion mass spectrometry and LC–MS results, while nuclear magnetic resonance analysis confirmed hydrogen abstraction from the tertiary carbon of CHDM units in the trans (equatorial-equatorial) conformation. Chain scission through Norrish Type II reaction is also responsible for the formation of carboxylic acid end group. Fluorescence emission from irradiated glycol modified poly(ethylene terephthalate) films demonstrated the formation of mono- and dihydroxyterephthalate species. Furthermore, FTIR and XPS valence band analysis confirmed configurational changes, in the polymer chain due to photodegradation. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47148.     

The Structure of the Irreversibly Bound Adhesion Promoter-Substrate Interfacial Layer of γ-Aminopropylsilanetriol on Crystalline Si,as Measured by XPS and FTIR

The irreversibly bound interfacial layer deposited by the γ-aminopropysilanetriol adhesion promoter onto a crystalline silicon substrate, which remains even after profuse washing, was found by XPS to have resulted from the fragmentation and rearrangement of the original γ-aminopropylsilanetriol molecule. A mechanism is proposed, involving the homolytic scission of the terminal N-C bond. One of the subsequent reactions is believed to involve hydrogen loss by abstraction and the formation of a terminal vinyl group, which bonds to the substrate. Support for this mechanism is found in IR spectroscopy of this layer.     

Simulation of the layer inversion phenomenon in binary liquid--fluidized beds by DEM–CFD with a drag law for polydisperse systems

Liquid-fluidized beds of particular binary mixtures exhibit the layer inversion phenomenon, a peculiar result of the mechanical equilibrium developing in such multiphase systems. Because of the crucial role of the hydrodynamic interaction, these are ideal test cases for assessing fluid-particle models in multi-particle CFD simulations. In the present work the layer inversion phenomenon is reproduced via Discrete Element Method (DEM) simulations, in which the drag force model for polydisperse systems described in Cello et al. (2010) is used. The simulations serve primarily to assess the suitability of the DEM–CFD approach and particularly the validity of the above drag model, although the results available may also prove very useful to investigate the prevailing mechanisms. To analyze a sufficiently broad variety of cases, involving different solid species, size ratios and operating conditions, three systems selected amongst the published literature are considered. The comparison of simulation and experimental observation is carried out in terms of overall bed and mixed layer interface heights, voidage and component distributions along bed height and time evolution of the species centers of mass. Simulations with liquid velocities below, above and at the critical inversion conditions are carried out. Additionally, simulations using a drag force model traditionally used for monodisperse beds are reported for comparison. The results not only demonstrate the importance of correctly accounting for the local size distribution in the bed, but also prove the validity of the overall computational approach. The predictions of the simulations are in good to excellent agreement with experiments, depending on the system considered, both in terms of critical velocity and, most notably, expansion of the individual components in the bed. The analysis of the hydrodynamics in the bed allows to investigate the local particle flow field, highlighting the presence of a steady irregular motion of the solids in apparently chaotic vortices continuously forming and disappearing, which is thought to be the mechanism responsible for mixing. The fluid–particle interaction forces exhibit a constant profile along bed height, even in the presence of a strongly non-uniform concentration profile.