Controllable synthesis of layered double hydroxide nanosheets to build organic inhibitor-loaded nanocontainers for enhanced corrosion protection of carbon steel.

The development of layered double hydroxide (LDH) nanosheets as nanocontainers has been intensively studied in recent years. Despite their potential for application on a large scale, their synthesis in an aqueous medium is rarely reported. Herein, we report a straightforward approach for the controllable synthesis of uniform MgAl-LDH nanosheets by an aqueous nucleation process followed by a hydrothermal treatment. The key to this method relies on the well-dispersed LDH nuclei that are produced by high-speed homogenization. Following the nucleation step, the coalescence of the aggregate hydroxide layers is diminished by hydraulic shear forces, leading to the disaggregation and even distribution of LDH nuclei. As a result, the oriented growth of individual crystals along the horizontal plane becomes predominant, leading to a high surface charge density of the hydroxide sheets and preventing their stacking. The electron microscope virtual proofs showed that the particles had a well-defined circular shape with a thickness of about 2-3 nm. Afterward, for the first time, LDH nanosheets were used to prepare LDH nanocontainers loaded with 2-benzothiazolythio-succinic acid (BTSA) by anion exchange. The incorporation of BTSA into the interlayer region and the emission behavior of the inhibitor were investigated. These results indicate that the prepared nanosheets can be utilized as effective nanocontainers for organic inhibitor loading and anti-corrosion application.

Controllable Synthesis of Hollow Silica Nanoparticles Using Layered Double Hydroxide Templates and Application for Thermal Insulation Coating.

The innovative hollow silica nanoparticle (HSN) material possesses substantial potential for application in the insulation field. The size and shell thickness of HSN are crucial factors in determining their inherent properties, which, in turn, impact their applicability. This research presents a facile approach to synthesizing HSN in which sodium silicate (Na2SiO3) was utilized as the silica precursor that can be directly deposited onto layered double hydroxide (LDH) nanoparticles without the utilization of any surfactant. A subsequent acid treatment was used to eliminate the templates, resulting in the formation of an HSN devoid of mesopores in silica shells. By utilizing various sizes of LDH cores, obtainable via coprecipitation followed by hydrothermal treatment, we were capable of successfully synthesizing the hollow particles with adjustable diameters ranging from 50 to 200 nm. In addition, the shell thickness is varied from 6.8 to 22.5 nm by varying the silicate solution concentration. Results demonstrate that prepared HSNs have low thermal conductivity and high reflectance in the UV-vis-NIR range (averaging 82.1%). These findings suggest that HSN can be utilized as an effective inorganic filler in the formulation of reflective and thermally insulating coatings.

Factor Associated With Teacher Satisfaction and Online Teaching Effectiveness Under Adversity Situations: A Case of Vietnamese Teachers During COVID-19.

How teachers perform and react to the world-wide pandemic and how the epidemic affects an education system may also be used as new conditions to consider the way to enhance SDG4 in developing countries. Regarding that concern, this study investigated 294 teachers' perspective on their teaching effectiveness and satisfaction during COVID-19. The findings underlined the significant roles of support from various stakeholders, school readiness toward digital transformation, and teachers' anxiety over teacher satisfaction. Notably, teachers' newly absorbed technological and pedagogical skills do elevate their teaching effectiveness but do not lead to higher satisfaction during the pandemic.

Dataset of Vietnamese students' academic perfectionism and school alienation.

Across the steadily superseding world, the younger generation is coming under pressure for an increase in the standard and a highly growing demand on their life themselves. This could lead to a variety of problems, including academic perfectionism and school alienation. To gain more insights into these phenomena, we conducted two research projects on students from eight upper secondary schools in Ho Chi Minh City, Vietnam using online surveys, and obtained two datasets. Dataset A covers (i) the level of students' perfectionism; (ii) belief in school meritocracy; (iii) The competitiveness among students; and (iv) the intrinsic motivation to achieve. Dataset B contains students' self-reports about (i) their perceptions of parents' and teachers' academic conditional regard; (ii) academic contingent self-worth; and (iii) school alienation. The numbers of respondents of dataset A and dataset B are 2942 and 2970, respectively.

Synthesis and characterization of polyaniline-hydrotalcite-graphene oxide composite and application in polyurethane coating.

In this paper, a composite from polyaniline and graphene oxide-hydrotalcite hybrid (PAN-HG) was fabricated by direct polymerization of aniline using ammonium persulphate as an oxidant in the presence of a HG hybrid. The structure and morphological properties of synthesized PAN-HG composites were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Raman spectra, and scanning electron microscopy (SEM) techniques. The electrochemical properties of the composite particles were also analyzed by potentiodynamic polarization curves to evaluate the corrosion inhabitation. The results were calculated by Tafel fitting and showed that the effective corrosion protection values were 73.11%, 88.46%, and 95.49%, corresponding to HG, 1PAN-HG, and 2PAN-HG. The influence of PAN-HG on the corrosion protection of the polyurethane coating applied on the CT3 steel was investigated. As a result, the PU containing 0.5% of 2PAN-HG showed the most effective protection of the CT3 steel substrate. The R C of the coating was about 1.61 × 107 Ω cm2, and after immersion for 30 days, the R C value was 0.17 × 106 Ω cm2. From all the analyzed results, PAN-HG has enhanced the corrosion protection and a complicated protection mechanism was also concluded and explained.

A review on the fabrication of several carbohydrate polymers into nanofibrous structures using electrospinning for removal of metal ions and dyes.

Water contamination by heavy metals and dyes has been one of the most severe problems globally. Various techniques have been employed to remove these contaminants from water, including adsorption and photocatalysis, which are highly efficient and environmentally friendly approaches. The overuse of traditional petroleum-based plastics in the production of filtration systems aggravates the status quo due to negative impacts on the environment. Bio-based polysaccharide polymers with the green and benign features and potential for commercial applications have been employed as feasible alternatives to replace synthetic polymers and reduce environmental impacts. With unique chemical composition, molecular weights, and functional chemical groups such as hydroxyl, amine, and carboxyl groups, carbohydrate polymers show multitude potentials for dye and metal ion chelation. This review focused on the fabrication of carbohydrate polymers, such as chitosan, cellulose, alginate, pullulan, starch, and hyaluronic acid, into nanofibrous structures using the electrospinning method and their environmental applications.

Dataset of Vietnamese teachers' habits and motivation behind continuous professional development programs participation.

In every educational system, teacher development has a vital role in its sector and the health of the social, cultural, and economic sectors. For this redeeming feature, all stakeholders such as education policymakers, school superintendents, and school faculties make a big room for teachers' improvement throughout continuous professional development (CPD) provisions. However, to embark on a new educational adventure is a challenging target to meet, especially when the teacher frames their teaching and learning concept years after years. We decided to survey Vietnamese teachers' habits and motivation to trace their origin back to teachers' partaking reason in these programs. This dataset acquisition occurred from 24 Sep 2019 to 26 Mar 2020 and approached public and private schools (using traditional, bi-lingual, or international curriculum). Overall, the dataset includes 464 observations (263 Vietnamese teachers and 202 expatriate teachers) from 48 K-12 schools across Vietnam. The researchers divided this dataset into three main sections, including (i) The demographic information; (ii) Teacher's CPD habits; and (iii) Teacher's perceptions concerning Project-based and Problem-based Learning (PBL).

Enhanced recovery programmes versus conventional care in bariatric surgery: A systematic literature review and meta-analysis.

BACKGROUND: With obesity prevalence projected to increase, the demand for bariatric surgery will consequently rise. Enhanced recovery programmes aim for improved recovery, earlier discharge, and more efficient use of resources following surgery. This systematic literature review aimed to evaluate the evidence available on the effects of enhanced recovery programmes after three common bariatric procedures: laparoscopic Roux-en-Y gastric bypass (LRYGB), laparoscopic sleeve gastrectomy (LSG), and one anastomosis gastric bypass (OAGB). METHODS: MEDLINE, Embase, the Cochrane Library and the National Health Service Economic Evaluation Database were searched for studies published in 2012-2019 comparing outcomes with enhanced recovery programmes versus conventional care after bariatric surgery in Europe, the Middle East and Africa. Data were extracted and meta-analyses or descriptive analyses performed when appropriate using R. RESULTS: Of 1152 screened articles, seven relevant studies including 3592 patients were identified. Six reported outcomes for 1434 patients undergoing LRYGB; however, as only individual studies reported on LSG and OAGB these could not be included in the analyses. The meta-analysis revealed a significantly shorter mean duration of hospital-stay for LRYGB enhanced recovery programmes than conventional care (mean difference [95% CI]: -1.34 days [-2.01, -0.67]; p<0.0001), supported by sensitivity analysis excluding retrospective studies. Meta-analysis found no significant difference in 30-day readmission rate (risk ratio [95% CI]: 1.39 [0.84, 2.28]; p = 0.2010). Complication rates were inconsistently reported by Clavien-Dindo grade, but descriptive analysis showed generally higher low-grade rates for enhanced recovery programmes; the trend reversed for high-grade complications. Reoperation rates were rarely reported; no significant differences were seen. CONCLUSION: These results support enhanced recovery programmes allowing shorter inpatient stay without significant differences in readmission rate following LRYGB, although complication and reoperation rate comparisons were inconclusive. Further research is needed to fill current data gaps including the lack of studies on LSG and OAGB.