Approximation of the Quadratic Double Centralizers and Quadratic multipliers on non-Archimedean Banach algebras

In this paper, we establish stability of quadratic double centralizers and quadratic multipliers on non-Archimedean Banach algebras. We also prove the superstability of quadratic double centralizers on non-Archimedean Banach algebras which are weakly commutative and weakly without order, and of quadratic multipliers on non-Archimedean Banach algebras which are weakly without order

A Novel Dual-Membranes WGS Reactor with Palladium Alloy and Polyvinyl Alcohol Membranes for Enhanced Hydrogen Recovery

A novel membrane reactor concept including palladium alloy membrane (selective to H2) and polyvinyl alcohol membrane (selective to CO2) is proposed for water gas shift reaction. The mathematical model of the reactor is developed for two reactor schemes, namely plug dual-membrane reactor (PDMR) and CSTR dual-membrane reactor (CDMR) with uni-dimensional and non-isothermal conditions. A comparison between PDMR and palladium alloy membrane reactor (PAMR) showed that PDMR volume becomes 30 % less than PAMR with 20 bar increase in feed pressure. Then the effect of Damkholer number, feed composition, and feed pressure on hydrogen recovery and CO conversion for PDMR and CDMR has been studied. Under the same operating conditions, CO conversion in PDMR is 10 % more than CDMR while its temperature decreases. The new proposed reactor configuration could pave the way for simultaneous production of hydrogen, increased CO conversion, and CO2 separation on an industrial scale

Performance of epoxy resin polymer as self-healing cementitious materials agent in mortar

This research investigated the application of epoxy resin polymer as a self-healing strategy for improving the mechanical and durability properties of cement-based mortar. The epoxy resin was added to the concrete mix at various levels (5, 10, 15, and 20% of cement weight), and the effectiveness of healing was evaluated by microstructural analysis, compressive strength, and non-destructive (ultrasonic pulse velocity) tests. Dry and wet-dry conditions were considered for curing, and for generating artificial cracks, specimens at different curing ages (1 and 6 months) were subjected to compressive testing (50 and 80% of specimen’s ultimate compressive strength). The results indicated that the mechanical properties in the specimen prepared by 10% epoxy resin and cured under wet-dry conditions was higher compared to other specimens. The degree of damage and healing efficiency index of this particular mix design were significantly affected by the healing duration and cracking age. An optimized artificial neural network (ANN) combined with a firefly algorithm was developed to estimate these indexes over the self-healing process. Overall, it was concluded that the epoxy resin polymer has high potential as a mechanical properties self-healing agent in cement-based mortar

Gelation Time of Hexamethylenetetramine Polymer Gels Used in Water Shutoff Treatment

Among the methods available to reduce water production, injecting a gelling system composed of a polymer and a crosslinker has been widely used. In this work, a hydrogel was prepared by crosslinking of an aqueous solution containing hexamethylenetetramine (HMTA) as crosslinker, hydrochloric acid (HCl) as an activator, and the co-polymer of 2-acrylamido-2methyl-propanesulfonic-acid sodium salt (AMPS) and acrylamide (PAMPS). In order to indicate the effective factors on the gelation time and also to develop the quadratic mathematical models, central composite design (CCD) was applied. Therefore, the main purpose was to establish functional relationship between the three factors (polymer concentration, HMTA, and hydrochloric acid) and a response (gelation time) by using a statistical technique. In order to determine the optimum value of these factors for maximum gelation time, a simultaneous optimization was also applied. The results of the analysis of variance (ANOVA) of the developed model illustrated that the fitted model was significant in a 99% confidence limit. The results showed that hydrochloric acid was identified as the main factor effecting the gelation time and there was also an interaction between HMTA and hydrochloric acid. Finally, a mechanism for the reaction between PAMPS and HMTA were presented

Confucian Principles: A Study of Chinese Americans’ Interpersonal Relationships in Selected Children’s Picturebooks

[[abstract]]There has not been enough critical analysis of children’s literature by and about Chinese Americans, especially when compared to other minority groups in the United States. In particular, Chinese American historical books lack extensive analysis. It is important to reflect cultural accuracy in literature and to help children develop clear concepts of self and others by providing precise cultural and physical characteristics of people. While cultural authenticity allows children the opportunity to see a reflection of real experiences within a book instead of seeing stereotypes or misrepresentations, obtaining correct information about a certain time period can help children to see images of immigration accurately represented in literature. Using the Confucian delineation of interpersonal relationships as the major criterion of cultural authenticity, this article examines three currently available children’s picturebooks set in the historical period between 1848 and 1885. In addition to exploring how Chinese Americans’ interpersonal relationships are portrayed in these children’s historical books, this article argues for more proactive inclusion of the diversity in selection of picturebooks.[[notice]]補正完

Development and characterization of a novel conductive polyaniline-g-polystyrene/Fe 3 O 4 nanocomposite for the treatment of cancer

The goal of this study is to synthesize, characterize and investigate some physicochemical properties of conductive polyaniline-g-polystyrene/Fe 3 O 4 (Fe 3 O 4 /PSt-g-PANi) nanocomposites. For this purpose, initially, Fe 3 O 4 nanoparticles were synthesized by a co-precipitation method. Then, the desired nanocomposite was synthesized in two steps. First, the atom transfer radical polymerization (ATRP) of styrene was performed using an ATRP initiator attached to the surface of Fe 3 O 4 nanoparticles, followed by functionalization of the Fe 3 O 4 -PSt with amine groups (�NH 2 ). Second, surface oxidative graft copolymerization of aniline was accomplished using the �NH 2 moieties on the Fe 3 O 4 /PSt-NH 2 as the anchoring sites. The prepared materials were characterized by various instruments, including TEM, SEM, TGA, EDX, FT-IR, XRD and conductivity measurements. The results indicated that the synthesized conductive polymer/Fe 3 O 4 nanocomposites had higher electrical conductivity and thermal resistance than those of the corresponding homopolymers. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group

MRI Tracking of Marine Proliferating Cells In Vivo Using Anti-Oct4 Antibody-Conjugated Iron Nanoparticles for Precision in Regenerative Medicine

Marine invertebrates are multicellular organisms consisting of a wide range of marine environmental species. Unlike vertebrates, including humans, one of the challenges in identifying and tracking invertebrate stem cells is the lack of a specific marker. Labeling stem cells with magnetic particles provides a non-invasive, in vivo tracking method using MRI. This study suggests antibody-conjugated iron nanoparticles (NPs), which are detectable with MRI for in vivo tracking, to detect stem cell proliferation using the Oct4 receptor as a marker of stem cells. In the first phase, iron NPs were fabricated, and their successful synthesis was confirmed using FTIR spectroscopy. Next, the Alexa Fluor anti-Oct4 antibody was conjugated with as-synthesized NPs. Their affinity to the cell surface marker in fresh and saltwater conditions was confirmed using two types of cells, murine mesenchymal stromal/stem cell culture and sea anemone stem cells. For this purpose, 106 cells of each type were exposed to NP-conjugated antibodies and their affinity to antibodies was confirmed by an epi-fluorescent microscope. The presence of iron-NPs imaged with the light microscope was confirmed by iron staining using Prussian blue stain. Next, anti-Oct4 antibodies conjugated with iron NPs were injected into a brittle star, and proliferating cells were tracked by MRI. To sum up, anti-Oct4 antibodies conjugated with iron NPs not only have the potential for identifying proliferating stem cells in different cell culture conditions of sea anemone and mouse cell cultures but also has the potential to be used for in vivo MRI tracking of marine proliferating cells. © 2023 by the authors

Snow White in different guises: Interlingual and intercultural exchanges between grandparents and young children at home in East London

Grandparents play a significant role in childcare and one activity that frequently occurs within this context is story-reading. However, relatively little attention has been given to the potential part that grandparents can play in terms of language and literacy development of young children.This article reports on work investigating the interlingual and intercultural exchanges occurring in a home setting in East London. In particular, it focuses on how the traditional heritage pattern of story and rhyme reading by a grandmother of Bengali origin is fused with practices experienced by her six-year old grandchild.The data reveal not only the multiple worlds inhabited by the grandchild during story-reading but also the syncretism of these worlds on a number of levels.This article contributes to the small but growing body of investigation into the reading styles occurring within families from different cultural backgrounds

Seawater concrete: A critical review and future prospects

Concrete production requires a large amount of water which causes a shortage of natural freshwater. Conversely, seawater in concrete can improve sustainability in construction by reducing the excessive consumption of natural freshwater. In the literature, the use of seawater in concrete still has a controversial reputation. It is, therefore, crucial to understand the properties of concrete mixed and cured with seawater. The past and recent research on seawater concrete is thoroughly reviewed in this paper and identifies the significant differences in characteristics between seawater concrete and conventional concrete. Existing studies indicate that high chlorides in seawater enhance the hydration rate, shorten the setting time and increase the early strength of concrete. In order to lessen the effect of chlorides and increase the durability of seawater concrete, mineral admixtures, retarders, and superplasticizers have been recommended. Past studies have also revealed that the use of seawater in concrete will inevitably corrode steel bars. This article covers the advantages and disadvantages of adopting FRP and stainless steel bars to prevent the corrosion of steel reinforcement caused by seawater. It also suggests future possibilities of using natural and recycled aluminum reinforcement in seawater concrete which not only protects concrete from corrosion but also leads to the sustainability of concrete. Overall, the outcomes of this study will contribute to further research aimed at improving the properties of seawater concrete

Evaluation of Solid Waste Management in the Chemistry Laboratories of Tehran Universities

Background and Objectives: Particular importance of hazardous wastes is due to having characteristics such as toxicity, flammability, corrosively and reactivity. Some of the chemical wastes due to having hazardous materials must be collected and managed in a proper manner, since they are potentially harmful to the environment. Owing to the fact that educational centers have important roles in developing countries, so the main objective of the present study was to investigate, hazardous waste management in chemistry laboratories of Ministry of Science universities, in Tehran, Iran.Materials and Methods: Study area of this research includes all chemistry laboratories in Tehran universities which were covered by Ministry of Science. To obtain the number of samples, based on Scientific Principles and identification formula, 64 samples were calculated. In addition, sampling was done by Stratified sampling. Validated checklists were used for data gathering. Data analysis were done by Descriptive statistics (mean, frequency and etc.) and inferential statistics (kruskal- wallis test).Results: results obtained in this study indicate that Sharif University by obtaining the mean score of 60.5 and Tehran University by obtaining the mean score of 4.5-6 are placed in best and worst rank, respectively. Beheshty, Alzahra and Tarbiat Moallem univesities by acquiring the mean score of 20-28.5 have a same position in ranking table.  Conclusion: Results show that most of the studied laboratories do not have any collection program and only 26.5 percent of them have acceptable programs.The separation and storing program observed in about 12.5 percent . Hazardous wastes management in chemistry laboratory of Tehran Universities was not in good status. And from the standpoint of management, only 12.5 percent of studied cases are in good status, while 75 percent was in undesirable status