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The efficiency of cloisite 30B nanoclay is assessed for the first time as a foaming agent to determine how these nanoparticles (NPs) affect the stability of the CO2 foam. The results of both bubble and bulk-scale foam stability measurements confirmed the efficacy of cloisite 30B NPs in improving the efficiency of CO2 foam. To compare the outcomes based on a reference, parallel experiments were conducted using silica NPs, a known promising foaming agent. By adding 0.1 wt% of nanoclay to a 0.12 wt% SDS surfactant solution, the foam decay time could be increased from 30 to 76 min. However, when the same concentration of silica NPs was used, the foam decay time was about 98 min. Furthermore, the foam injection practices showed that the foams stabilized by silica NPs and cloisite 30B nanoclay yielded 22.8% and 12.9% more oil, respectively, during foam injection into sister sandstone plugs. Moreover, we showed that stabilized foams containing cloisite 30B NPs resulted in a slightly lower final permeability compared to foams containing silica due to the retention of NPs. Both core samples underwent post-water flooding after foam injection, and then the used plugs were dried and the final gas permeability of each sample was compared to its initial value to check whether any of the used NPs might have blocked the pores. Our findings indicated that, despite the nanoclay's ability to increase foam stability and yield more oil recovery than void-NPs foam, it could not be an alternative for the frequent silica NPs. [ABSTRACT FROM AUTHOR]

This paper presents a study investigating the potential market of ridesourcing services, with a focus on the attitudinal and preferential differences between Millennials and Generation Xers. Data obtained from a stated preference survey were utilized, where the respondents were asked to choose between a conventional mode (private vehicle driver, transit, or private vehicle passenger) and ridesourcing modes (exclusive ride and shared ride). Error component nested logit models were developed for Generation Xers and Millennials, respectively. Latent attitudes derived through factor analysis were incorporated into models. A wide range of attitudinal indicators, including general mobility attitudes, perceived benefits and concerns of shared mobility services, reasons for or against owning a car, reasons for ridings Autonomous Vehicles (AV), and the most desired AV features were considered to extract latent attitudes. Model results indicated distinct mode choice behavior between Millennials and Generation Xers. For Generation Xers, the choice to switch to ridesourcing was highly dependent on the perceived time and cost benefits of shared mobility. On the other hand, Millennials' choices were more likely to be influenced by their attitudes or desire toward technology, on-demand services, and driving stress relief. Interestingly, the joy of driving showed a negative impact on Millennials' use of shared-ride services only. The findings from this study provide a more in-depth understanding of the distinct behavior of Generation Xers and Millennials toward shared mobility services, which could help develop strategies and policies to focus more effectively on the needs and concerns of individuals based on their characteristics and attitudes and help promote sustainable transportation system. [ABSTRACT FROM AUTHOR]

Purpose: To systematically review the published manuscripts on stereopsis after corneal refractive surgery. Methods: The Web of Science, PubMed, Scopus, ProQuest, Clinical Key, Embase, and Cochrane Library were searched for relevant articles published until August 2020. The fixed- or random-effects models were used to estimate the Weighted mean difference (WMD) or Relative risk (RR) and 95% Confidence interval (CI) for postoperative stereopsis changes and incidence when applicable. Meta-regression was conducted for adjusting the effects of potential confounders. Results: Seven studies (1266 eyes) in adults and ten studies in pediatrics (259 eyes) were included. In adults, stereopsis improved significantly compared to the preoperative state (WMD = − 27.4, 95% CI = − 40.0, − 14.7; I2 = 97.8%; P < 0.001). In pediatrics, proportion of patients with stereoacuity postoperatively was 2.18 times compared to preoperative evaluation. (RR = 2.18, 95% CI = 1.2, 3.9; I2 = 68.6%, P < 0.001). Conclusions: Stereopsis improves after corneal refractive surgery in adults and pediatrics. [ABSTRACT FROM AUTHOR]

Marine coatings protect submerged surfaces from the negative effects of biofouling. In this work, we demonstrate a new method to prepare self-stratified, amphiphilic glycidyl-carbamate (GC)-based (epoxy urethane-based) coatings (AmpSiGC coatings) that have fouling-release properties making them suitable for marine use. The prepared coating systems are unique and durable in character as the bulk coating takes advantage of both epoxy and urethane functionalities while the surface is comprised of both hydrophilic and hydrophobic domains, granting it an amphiphilic characteristic. The experimental approach aimed to evaluate several factors that influence coating performance, including molecular weight of poly (ethylene glycol) (PEG) and PDMS moieties, ratio of hydrophobic (PDMS) and hydrophilic (PEG) components in the system, and the effect of different curing agents. The results demonstrated that polymeric chains of 10,000 M ¯ n PDMS and 750 M ¯ n PEG at 10–15 wt.% each offer substantially improved or comparable fouling-release performance in comparison to commercial marine coatings. This paper reports on the facile synthesis and characterization of the GC resin and GC prepolymers using FTIR and epoxy titrations; surface characterization of the coatings using ATR-FTIR, XPS, and AFM; and fouling-release assessment of the surfaces using laboratory biological assays with the barnacle Amphibalanus amphitrite, the algae Ulva linza and Navicula incerta, and the bacteria Cellulophaga lytica. Several of the AmpSiGC coatings exhibited promising performance, which were better or comparable to the internal and commercial reference coatings. The performance of the systems was dependent on all of the factors considered in this study. [ABSTRACT FROM AUTHOR]

Icephobic coatings have applications in many industries to protect surfaces from deterioration and avoid catastrophic incidents. In this work, we report a new strategy to prepare amphiphilic siloxane-glycidyl carbamate coatings (AmpSiGC) coatings with anti-icing property. Polydimethyl siloxane (PDMS) and poly(ethylene glycol) (PEG) provided amphiphilicity for the AmpSiGC coatings. The designed experiment considered several factors: molecular weight of the surface-modifying polymers and their amount in the coating system. Although amphiphilic coatings have demonstrated promising results as marine coatings, investigations on their icephobic applications have been limited. This work discusses three aspects of the developed AmpSiGC systems: (1) preparation of the incorporated ingredients and their characterization by Fourier transform infrared spectroscopy (FTIR); (2) surface characterization of coatings via ATR (attenuated total reflectance)-FTIR, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM); and (3) ice-adhesion, electrochemical impedance spectroscopy (EIS), and mechanical property evaluations. Overall, the surface analysis indicated the presence of both hydrophobic and hydrophilic domains and most of the coatings demonstrated promising performance for anti-icing applications with desirable barrier and mechanical properties in comparison to controls. [ABSTRACT FROM AUTHOR]

This study aims to investigate the micromixing performance of three basic types of spatial shaped micromixers. New configurations of T, Y, and oriented Y -spatial mixers were designed with change in the angles of the confluence and the outlet channel to achieve the efficient micromixing. These micromixers offer advantages that are not attainable with the typical types of these mixers. Experimental tests were carried out in the laminar flow regime and the mixing efficiency was evaluated using Villermaux/Dushman test reaction. The geometries of the channels were cylindrical with the length of 30 mm and the diameter of 800 μm. The experimental results show that the angle of outlet channel has a significant effect on the pressure drop and segregation index. Generally, the results reveal that at various feed flow rates the spatial shape of channels can lead to considerable improvement in micromixing performance. In all T, Y, and oriented Y -mixers, significant enhancement by increasing the confluence angle was also seen because the fluid elements were stretched and folded in the two inlet fluid interfaces. Furthermore, the micromixing time for the more efficient geometry of three shapes of microchannels was determined based on the incorporation model, which it was in the range of 0.001-0.1 s. [ABSTRACT FROM AUTHOR]

Lignin is a heterogeneous aromatic biopolymer that accounts for nearly 30% of the organic carbon on Earth and is one of the few renewable sources of aromatic chemicals. As the most recalcitrant of the three components of lignocellulosic biomass (cellulose, hemicellulose and lignin), lignin has been treated as a waste product in the pulp and paper industry, where it is burned to supply energy and recover pulping chemicals in the operation of paper mills. Extraction of higher value from lignin is increasingly recognized as being crucial to the economic viability of integrated biorefineries. Depolymerization is an important starting point for many lignin valorization strategies, because it could generate valuable aromatic chemicals and/or provide a source of low-molecular-mass feedstocks suitable for downstream processing. Commercial precedents show that certain types of lignin (lignosulphonates) may be converted into vanillin and other marketable products, but new technologies are needed to enhance the lignin value chain. The complex, irregular structure of lignin complicates chemical conversion efforts, and known depolymerization methods typically afford ill-defined products in low yields (that is, less than 10-20wt%). Here we describe a method for the depolymerization of oxidized lignin under mild conditions in aqueous formic acid that results in more than 60wt% yield of low-molecular-mass aromatics. We present the discovery of this facile C-O cleavage method, its application to aspen lignin depolymerization, and mechanistic insights into the reaction. The broader implications of these results for lignin conversion and biomass refining are also considered. [ABSTRACT FROM AUTHOR]

We prepared high selective imprinted nanoparticle polymers by a miniemulsion polymerization technique, using risperidone as the template, MAA as the functional monomers, and TRIM as the cross-linker in acetonitrile as solvent. The morphology of the nanoparticles determined by scanning electron microscopy (SEM) images and drug release, binding properties and dynamic light scattering (DLS) of molecularly imprinted polymers (MIPs) were studied. Controlled release of risperidone from nanoparticles was investigated through in 1% wt sodium dodecyl sulfate aqueous solution and by measuring the absorbance by HPLC-UV. The results showed that the imprinted nanoparticles exhibited a higher binding level and slower release rate than non-imprinted nanoparticles, which contributed to interaction of risperidone with imprinted cavities within nanoparticles. Furthermore, the results from HPLC showed good precision (5% for 50.0 μg L) and recoveries (between 86-91) using MIP from human plasma samples. [ABSTRACT FROM AUTHOR]

Background: There is growing evidence that memantine, a noncompetitive N-methyl- d-aspartate receptor antagonist, may be applied as an add-on in treating patients suffering from obsessive-compulsive disorders (OCD). The aim of the present study was therefore to assess the effect of adjuvant memantine in a double-blind, randomized, and placebo-controlled study of the treatment of patients suffering from OCD. Method: A total of 40 inpatients (32 females (80 %); mean age = 31.25 years) suffering from OCD were randomly assigned to a treatment (administration of memantine) or a control group (placebo). Treatment lasted for 12 consecutive weeks. All patients were treated with selective serotonin re-uptake inhibitors or clomipramine. Patients completed the Yale-Brown Obsessive Compulsive Scale four times. Experts' ratings consisted in clinical global impression (clinical global impressions (CGI), illness severity and illness improvement; two to three times). Liver enzymes SGOT and SGPT were also assessed (twice). Results: Of the 40 inpatients approached, 29 completed the 12 consecutive weeks of the study. Of the 11 dropouts, 6 were in the target group and five in the control group. Symptoms significantly decreased across the period of the study, but particularly in the treatment compared with the control group (significant time × group interaction). Illness severity (CGI severity) also significantly decreased over time but more so in the treatment than in the control group (significant time × group interaction). Illness improvements (CGI improvements) were not significant. Conclusions: The pattern of results from the present double-blind, randomized, and placebo-controlled study for the treatment of patients suffering from OCD suggests that adjuvant memantine does significantly and favorably impact on OCD. [ABSTRACT FROM AUTHOR]