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The Computational Fluid Dynamics (CFD) technique was used to study the effect of the geometrical parameters on the intensification of hydrodynamic parameters and Carbon dioxide (C O 2) absorption efficiency by Mono-Ethanol-Amine (MEA) solution in a novel Arc-blade Rotating Packed Bed reactor (Arc-RPB). The VOF multiphase approach and RNG k - ε turbulent model were used to study the multiphase and turbulent behavior of the flow field in the computational domain, respectively. The effects of liquid flow rate, the bed wire mesh diameter, and number of the mesh layers were studied on the liquid holdup (α L) , gas-liquid interfacial area (A int) and liquid dispersion index (I d). Considering the Arc-RPB bed wire mesh diameter from 0.2 mm to 1.6 mm showed that α L , A int and I d decrease 20%, 29% and 11%, respectively. By examining the effect of the bed layers enhancement, the liquid holdup α L decreased by about 36% but, A int and I d reached a maximum value at 16 bed layers. Finally, with study the effect of the bed geometrical parameters on C O 2 absorption efficiency, results showed the efficiency reduces about 7.5% with increase in the bed mesh diameter and shows a maximum at 16 bed layers. [Display omitted] • Study of geometrical parameters effects on the hydrodynamic characteristics of a novel Arc-RPB by CFD simulation. • High effect of bed wire mesh and bed layer number in intensification of absorption efficiency of C O 2 by MEA solution. • Dependence of absorption efficiency to the liquid dispersion index. [ABSTRACT FROM AUTHOR]

The present study aimed to compare the effectiveness of music and playing with Lego in postoperative management pain in children. In this three-group quasi-experimental study, the participants in this interventional study were 96 children aged 6 to 12 years admitted to the pediatric surgery ward of Mofid Hospital and Medical Center in Tehran. The participants were selected using convenience sampling. They were then randomly placed into three intervention groups. Pain intensity was measured for the participants in all three groups before the intervention. The intervention was performed in two 15-min sessions with an interval of 5 min in three intervention groups. Then pain intensity was measured using the Oucher Pain Scale before the intervention and in four intervals: Immediately after the intervention, half an hour, one hour, and 3 h after the intervention, respectively. Pain intensity was also measured at the same time intervals for the participants in the control group. The collected data were analyzed with SPSS-25 software using descriptive statistics, the Bonferroni test, and Tukey's test. The data showed that the three groups were identical in terms of demographic characteristics (p > 0.05).A comparison of the music listening group and the control group showed statistically significant difference in terms of postoperative pain (P < 0.05).However, the data showed significant differences between the control group and the Lego group in terms of pain intensity immediately after the intervention, half an hour, one hour, and 3 h after the intervention, respectively (p < 0.05).The data also revealed a significant difference between the children in the music group and the Lego group at all phases (p < 0.05), and the children in the Lego group reported less pain after the intervention compared to the children in the music listening group. Nevertheless, there was a statistically significant difference between the three groups in terms of reported pain intensity half an hour, one hour, and three hours after the intervention (p < 0.05). The results showed that playing with Legos had a greater effect on reducing postoperative pain in children than listening to music. Thus, nurses are recommended to make arrangements for children to play with Legos after surgery. Playing with Legos can be used to control postoperative pain in school-age children in medical centers and wards of pediatric hospitals. • Approved by the Committee of Ethics in Shahid Beheshti University of Medical Sciences (IR.SBMU.PHARMACY.REC.1399.321). • Playing with Legos had a greater effect on reducing postoperative pain in children than listening to music. • Nurses are encouraged to provide an appropriate condition for children to play with Legos after surgery. [ABSTRACT FROM AUTHOR]

In the present work, two different models (micro-scale and meso-scale) were developed to investigate the heat transfer between the gas and liquid phases in the trickle flow regime of a packed bed reactor. In the micro-scale model, a simplified description of bed geometry, known as the double-slit model, was implemented to study the effects of different operating parameters, in terms of gas and liquid Reynolds, Prandtl and Eötvös numbers, on the interfacial Nusselt number. In the meso-scale model, the Volume-of-Fluid (VOF) approach was used to simulate trilobe, cylindrical and spherical catalyst shapes and accurately predict the effects of interface morphology and bed geometry on interfacial heat transfer. To validate the implemented methods, a simple packed bed reactor with spherical catalysts was developed to experimentally investigate the interfacial heat transfer of co-current, downward gas–liquid film flows. The results obtained from CFD simulations and experimental data were in agreement and accurately predicted bed reactor temperature profiles with a mean relative error of 2.15%. In both the micro- and meso-scale models, an increase in the Reynolds and Prandtl numbers increased the interfacial Nusselt number; whereas, an increase in dimensionless groups of the liquid phase or the Eötvös number caused the opposite effect. Finally, a new correlation was proposed that evaluated the gas–liquid Nusselt number in the trickle flow regime with a standard deviation of 7.19% compared to results acquired using the micro-scale model. [ABSTRACT FROM AUTHOR]

Abstract: For productive manufacturing of an accurate small-scale wine-glass gyroscope, a hybrid fabrication process consisting of either electric discharge machining, chemical etching, or micro-mechanical milling have been proposed. A comparison of silicon cavity fabrication processes has been conducted in terms of productivity, quality and geometrical accuracy, aiming at the use of the cavity as a mold for creating a thin wall diamond hemisphere, which is the main component of a wine-glass gyroscope. The results have shown that the EDM process, combined with chemical etching, can yield the highest productivity but with limited shape accuracy. The use of mechanical micro-milling, while less productive than EDM and etching, produces a superior quality and geometric accuracy. [Copyright &y& Elsevier]

Abstract: Nanopaper was prepared using ground cellulose nanofibers (GC) from canola straw and bacterial cellulose nanofibers (BC). The characteristics of GC and BC nanopapers were investigated and compared. Micropaper was also prepared from as-bleached cellulose microfibers of canola straw, used as a control sample to evaluate the effect of grinding on the properties of cellulose nanofibers and nanopaper. The average diameters for the microfiber, GC and BC were 26μm, 32nm and 45nm, respectively. Micropaper had crystallinity and crystallite size of 69% and 5.5nm, respectively. As the result of grinding, the crystallinity and crystallite size of GC nanopaper dropped to 62% and 5.1nm, respectively. BC nanopaper showed the highest values, with 80% and 6.2nm, respectively. GC nanopaper had a lower onset temperature (270°C) and thermal stability than that of both micropaper (275°C) and BC nanopaper (320°C). Micropaper was permeable to air while GC and BC nanopapers showed very high barrier property. Grinding had a drastic positive effect on mechanical properties: the tensile strength and Young''s modulus of GC nanopaper increased 11 times on average over those of micropaper, reaching 114MPa and 13.6GPa, respectively. BC nanopaper had the highest tensile strength and Young''s modulus, with 185MPa and 17.3GPa, respectively. GC and BC nanopapers are regarded as highly tough, fully bio-based, fully biodegradable and multi-performance materials. [Copyright &y& Elsevier]

• Introducing a new framework for a TVPP in different energy markets. • Examining the abilities of local heat markets in improving a TVPP's performance. • Proposing the model in a multi-carrier energy environment. • Extracting the optimization model as a bi-level problem. Distributed energy resources (DERs) play an important role in the future vision of distribution energy networks. This paper with the aim of promoting DERs role in energy markets proposes a new framework for the optimal bidding strategy of a Technical Virtual Power Plant (TVPP) in different markets. In the proposed framework, it is assumed that the TVPP energy power is distributed throughout a multi-carrier energy network (MCEN) which consists of district heat networks (DHNs) and a distributed electricity network (DEN). In the MCEN, CHP units are the linkage between DHNs and DEN. With the goal of maximizing the profit of TVPP in different local and wholesale energy markets, a bi-level optimization model is formularized to set scheduling of DERs. As the upper level, the TVPP sets the schedule of its DERs considering technical constraints of DHNs and DENs. In the lower level, however, the TVPP runs an optimization problem to estimate the energy price in wholesale energy markets considering the forecasted bids of other rivals. The proposed model is implemented on a test system and the results confirms that the local market creates an opportunity for CHP owner, TVPP and the heat consumers to make more profit as well as achieving better technical performance for distribution energy systems. [ABSTRACT FROM AUTHOR]