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This study explores the effectiveness of silicon quantum dots (SiQDs)—specifically, amine-functionalized (NSiQDs) and amine-hydroxyl-functionalized (NOSiQDs)—in optimizing thin-film nanocomposite (TFN) membranes for pervaporation dehydration of various alcohols. The SiQDs were integrated into the membranes via an innovative interfacial polymerization technique, involving the dispersion of SiQDs in an aqueous amine solution followed by polymerization with trimesoyl chloride. This approach ensured uniform integration of SiQDs, significantly enhancing the nanostructure and surface characteristics of the membranes. Such modifications led to improved water transport capabilities, substantially boosting pervaporation efficiency. Exceptional performance was demonstrated by the TFN-NOSiQDs(400) membranes, which achieved a peak permeation flux of 4195.8 g·m−2·h−1 and maintained over 99 wt% water concentration in the permeate when tested with a 70 wt% isopropanol/water solution at 25°C. Comprehensive long-term stability assessments confirmed the robustness and consistent functionality of the membranes, highlighting their suitability for industrial applications that demand reliable and efficient alcohol separation processes. [Display omitted] • NSiQDs and NOSiQDs enhance pervaporation efficiency. • TFN membranes exhibit high long-term stability. • Optimal NSiQDs and NOSiQDs concentrations identified. • Improved membrane hydrophilicity with SiQDs. • High separation efficiency maintained across tests. [ABSTRACT FROM AUTHOR]

• Metal-organic framework, HKUST-1 was embedded in polyelectrolyte layer. • Dispersing of HKUST-1 in polycation produced stable polyelectrolyte structure. • Polyelectrolyte/HKUST-1 membrane had high efficiency for dehydration of THF. • Polyelectrolyte/HKUST-1 membrane had stable performance for long-term. Enhancing composite membrane performance is crucial for industrial separation processes. Integrating metal-organic frameworks (MOFs) into membranes offers a promising strategy. We introduce a novel approach by integrating HKUST-1 MOF within a polyelectrolyte matrix to improve membrane efficiency. A layer-by-layer self-assembly technique on a hydrolyzed polyacrylonitrile support integrates HKUST-1 into a polyelectrolyte matrix. Polyethyleneimine (PEI) and polyacrylic acid (PAA) form the polyelectrolyte layer through electrostatic interactions. The incorporation of HKUST-1 within the PEI matrix enhances separation efficiency, particularly in tetrahydrofuran dehydration, with optimal conditions using 100 ppm of HKUST-1 and forming 2 bilayers. Under optimal conditions, the resulting membrane exhibits exceptional performance. It demonstrates a permeation flux of 1442.30 g∙m−2∙h−1, a water concentration in the permeate of 98.0 wt%, and a separation factor of 440. The modified membrane also shows remarkable stability across varying temperatures (25–55 °C) and tetrahydrofuran concentrations in the feed (10–90 wt%) during long-term testing. These findings highlight the membrane's potential for enhancing separation processes in the chemical industry. [Display omitted] [ABSTRACT FROM AUTHOR]

• Zwitterionic MOF (UiO-66-Z) was embedded in a thin-film composite membrane. • UiO-66-Z tailored the surface property of the membrane. • UiO-66-Z enhanced the separation efficiency of thin-film composite membrane. This study explores the integration of zwitterionic UiO-66, a metal-organic framework (MOF) particle, within a polyamide-based thin-film composite membrane for dehydrating aqueous isopropanol solutions. UiO-66-Z was synthesized from UiO-66-(COOH)2 and subsequently dispersed in an aqueous diethylenetriamine (DETA) solution, followed by reaction with trimesoyl chloride (TMC) through vacuum-assisted interfacial polymerization. ATR-FTIR analysis confirmed the presence of zwitterionic moieties in UiO-66-Z, whereas XPS analysis verified its presence on the membrane surface. Embedding UiO-66-Z led to increased nodularity on the membrane surface, enhancing surface roughness and potentially improving membrane efficiency. The presence of UiO-66-Z during interfacial polymerization hindered the reaction between DETA and TMC, resulting in a thin polyamide layer. Optimal UiO-66-Z concentration was found to be 5 ppm, achieving a water permeation flux of 1342 g·m−2·h−1 with >99% water content in the permeate when separating a 70% isopropanol/water solution. Furthermore, the TFN-5 membrane demonstrated excellent stability across various operating conditions and during long-term testing. [Display omitted] [ABSTRACT FROM AUTHOR]

• Ultra-high performance polyamide thin-film composite membrane was fabricated. • Polyamide layer was deposited on top of cellulose triacetate (CTA) support. • Using CTA support delivered higher performance compared to polysulfone support. Choosing the property of the supporting membrane is crucial in preparing high performing nanofiltration membranes through interfacial polymerization. In this study, an oxygen rich membrane – cellulose triacetate (CTA) – was used to fabricate the support membrane. Polyamide was deposited onto the CTA support using interfacial polymerization of piperazine (PIP) and trimesoyl chloride (TMC). The concentration of the monomers was optimized. Furthermore, the polyamide layer prepared on CTA support exhibited higher separation efficiency for sodium sulfates and dyes compared to using traditional polysulfone (PSf) support. The oxygen groups of CTA facilitate better adsorption of amines on the surface; thus, using low concentration of PIP could still provide a defect-free polyamide layer. Utilizing the optimum condition, the polyamide/CTA membrane delivered a high pure water flux (operating at 6 bar) of 179.5 L/m2h with the following rejections: Na 2 SO 4 = 98.4%; MgSO 4 = 60.3%; MgCl 2 = 15.0%; NaCl = 3.7%; Rose Bengal = 95.5%; Brilliant Blue R = 99.9%; Amido Black 10B = 90.6%; Orange G = 67.3%. Moreover, the polyamide/CTA membrane had excellent stability at a wide range operating conditions. [ABSTRACT FROM AUTHOR]

Virtual learning can provide an environment to reduce the waste of test material and immersive. Currently, the welding technique also uses the virtual learning environment for training skills. The contest integrating learning technology for developing a mobile application by students, such as Augmented Reality, virtual Reality. In the contest, students need to cooperation with different country students and integrating their idea in to a new mobile application. They also need to provide project proposal, promoting video, pitch deck and the complete mobile application. Above all, we developing an interdisciplinary course through the operation of the teacher community. Understand the content of subject learning by consulting teachers in different disciplines and try to find out where they can integrate. The complete curriculum development was construct by three teachers major in mechanical, electronic, and math. The development of curriculum can provide school that need to construct transdisciplinary learning. [ABSTRACT FROM AUTHOR]

Manufacturing content knowledge is an important part for Mechanical Engineering Students. In Taiwan, two path for high school students to learn mechanical engineering content, general high school or technique high school. For technique high school students, they would learn basic mechanical engineering content through practical course and lecture in-class. Generally, the connection between practical course and in-class course are weak. Students hardly learn to connect the manufacturing content with practical course. Therefore, students need more effective method to connect the content. Focus group discussions is one of effective method to connect learning activities with content knowledge. It based on participates' observation and reflection ability. In this study, we proposed to use focus group discussions as a framework for practical courses in high school. Students who learning manufacturing content knowledge, metal welding by practical course. Based on the background and motivation, we investigated two research questions as follows: (1) Does student learning with focus group discussions to acquire manufacturing content knowledge better than without FGD?; (2) What is the difference between student learning with and without focus group discussions to acquire manufacturing content knowledge? According to the result, we found that learn manufacturing content knowledge with FGD in a practical course can improving student learning performance. It can provide a reference for teachers who teach the practical courses. For future work, we would deeply find the correction between different backgrounds of the student, like learning style, course interesting. [ABSTRACT FROM AUTHOR]

In this work, a thin-film nanocomposite (TFN) membrane was constructed using a hybrid polydopamine (PD)-MoS 2 (MoS 2 @PD) filler for pervaporation dehydration of isopropanol. The exfoliated MoS 2 was first modified through bio-inspired coating of PD. The resulting MoS 2 @PD with different weight ratio with respect to PEI was then deposited into the hydrolyzed polyacrylonitrile support through pressure-assisted filtration, followed by crosslinking with trimesoyl chloride. Characterization experiments were performed with the membranes using Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy, X-Ray Photoelectron Spectroscopy, Energy-Dispersive X-ray Spectroscopy, Field Emission Scanning Electron Microscopy, Atomic Force Microscopy, and water contact angle analyses. The PD serves as a bridging agent between MoS 2 and the crosslinked PEI, enhancing the membrane's physicochemical properties, including surface morphology and hydrophilicity. For membrane performance on pervaporation dehydration of 70/30 wt% isopropanol/water mixture at 25 °C, the addition of MoS 2 @PD led to a simultaneous increase in permeation total flux and water content in the permeate. Notably, MoS 2 @PD 0.3 -TFN membrane demonstrated a permeation flux of 2870.10 g∙m−2∙h−1 and 0.86/99.14 wt% isopropanol/water permeate mixture. The membrane also maintained stable performance under varying feed concentration, feed temperature, and long-term operations. This study contributes valuable insights into the development of MoS 2 -based membrane with enhanced pervaporation separation performance. • 2D MoS 2 was facilely modified with polydopamine to prepare a hybrid filler. • Incorporating MoS 2 @PD rendered the nanocomposite membrane a modulated physicochemical properties and hydrophilicity. • MoS 2 @PD 0.3 -TFN membrane exhibited the highest pervaporation separation for isopropanol-water mixture. • The MoS 2 @PD 0.3 -TFN membrane demonstrated a robust pervaporation performance at different operating conditions. [ABSTRACT FROM AUTHOR]

The carbon quantum dot/titanium dioxide (CQDs/TiO 2), fabricated on highly porous polyimide (PI)/polyether sulfone (PES) nanofiber via electrospinning process, called the dual-functional CQD/TiO 2 @PI/PES membrane, was developed and evaluated for its performance, including both removal of volatile organic compounds (VOCs) and ultrafine particulate matters (PM 0.1). The photocatalytic activity of synthesized CQD/TiO 2 @PI/PES membranes with 5% CQD loading on the decomposition of acetone was significantly enhanced compared with that of TiO 2 (P25)@PI/PES. The comprehensive results of photoluminescence emission, X-ray photoelectron spectroscopy, and photocatalytic experiments suggest that up-conversion properties of CQD can enhance the absorption of visible light on TiO 2 and reduce the reorganization of electron-hole pairs. Further, the optimized CQD/TiO 2 @PI/PES membrane could effectively photodegrade of acetone (>94.5%) and also maintained a good PM0.1 filtration efficiency (> 99%) and a differential pressure of 0.34 Pa for creating level 3 medical face masks as per the standards of ASTM F2299 and EN 14683. Therefore, the dual-functional CQD/TiO 2 @PI/PES membrane could be applied as a promising photocatalytic filter for air purification that simultaneously and remarkably filters PM0.1 and decompose VOCs. [Display omitted] • Dual-functional CQD/TiO 2 @PI/PES membrane was used to remove VOCs and PM 0.1. • CQD/TiO 2 @PI/PES membrane could effectively photodegrade of acetone (>94.5%). • CQD/TiO 2 @PI/PES membrane maintained a good PM0.1 filtration efficiency (> 99%). • Acquiring a differential pressure of 0.34 Pa for creating level 3 medical face masks. [ABSTRACT FROM AUTHOR]

Highlights • Polyelectrolyte/HPAN hollow fiber membrane for pervaporation was explored. • Single bilayer membrane was fabricated by self-assembly technique. • Effect of hydrolyzed and self-assembly conditions on the performances were investigated. • Pervaporation operating conditions were also investigated. Abstract In recent years, layer-by-layer self-assembly technology is one of the methods of preparing thin film composite membrane with ultra-thin selection layer. In this study, a single bilayer polyelectrolyte/hydrolyzed polyacrylonitrile (HPAN) hollow fiber membranes were fabricated by self-assembly technique for pervaporation. Branched polyethyleneimine (BPEI) and polyacrylic acid (PAA) were used as the cation polyelectrolyte and anion polyelectrolyte, respectively. Polycation/HPAN composite hollow fiber membranes were prepared by self-assembling BPEI onto the outer surface of HPAN hollow fiber membranes through electrostatic interaction. Subsequently, polycation/HPAN composite hollow fiber membranes were self-assembled with PAA to form polyanion/polycation/HPAN composite hollow fiber membranes. The effect of hydrolyzed and self-assembly on the property and pervaporation performances of aqueous ethanol solution through resulted hollow fiber membranes were investigated. By using the BPEI/PAA self-assembly, a single bilayer polyanion/polycation/HPAN composite hollow fiber membrane with excellent pervaporation performances was obtained. Furthermore, the effects of pervaporation conditions such as feed concentration, feed temperature, and downstream pressure on the pervaporation performances through BPEI/PAA/HPAN composite hollow fiber membranes were also investigated in this study. Graphical abstract Image, graphical abstract [ABSTRACT FROM AUTHOR]

Background/purpose β-Tricalcium phosphate (β-TCP) is an osteoconductive material which has been used for clinical purposes for several years, as is polycaprolactone (PCL), which has already been approved for a number of medical and drug delivery devices. In this study we have incorporated various concentrations of β-TCP into PCL with the aim of developing an injectable, mechanically strong, and biodegradable material which can be used for medical purposes without organic solvents. Materials and methods This study assesses the physical and chemical properties of this material, evaluates the in vitro bioactivity of the PCL/β-TCP composites, and analyzes cell proliferation and osteogenic differentiation when using human bone marrow mesenchymal stem cells (hBMSCs). Results The results show that weight losses of approximately 5.3%, 12.1%, 18.6%, and 25.2%, were observed for the TCP0, TCP10, TCP30, and TCP50 composites after immersion in simulated body fluid for 12 weeks, respectively, indicating significant differences (P < 0.05). In addition, PCL/β-TCP composites tend to have lower contact angles (47 ± 1.5° and 58 ± 1.7° for TCP50 and TCP30, respectively) than pure PCL (85 ± 1.3°), which are generally more hydrophilic. After 7 days, a significant (22% and 34%, respectively) increase (P < 0.05) in alkaline phosphatase level was measured for TCP30 and TCP50 in comparison with the pure PCL. Conclusion PCL/TCP is biocompatible with hBMSCs. It not only promotes proliferation of hBMSCs but also helps to differentiate reparative hard tissue. We suggest 50% (weight) PCL-containing β-TCP biocomposites as the best choice for hard tissue repair applications. [ABSTRACT FROM AUTHOR]

• Nanozeolite was undergone alkaline treatment. • Alkali-treated nanozeolite had good dispersion in organic phase solution. • Modified nanozeolite was well-dispersed in thin-film nanocomposite membrane. • Both permeation flux and water concentration in permeate was improved. Thin-film nanocomposite (TFN) membrane separates water from alcohols effectively. However, during fabrication of TFN membrane, the dispersion of inorganic nanoparticle in the solvent media limits its used. Nanozeolite, a natural inorganic particle, was modified through alkaline treatment using NaOH or NaHCO 3. Both alkaline indeed improved the dispersion of nanozeolite in trimesoyl chloride (TMC)/n-hexane solution. TFN membrane had been prepared through interfacial polymerization of diethylenetriamine (DETA) and TMC, forming a thin selective polyamide layer on top of hydrolyzed polyacrylonitrile (mPAN) support. The pore size of the nanozeolite was also enlarged due to the etching by the alkaline. Nanozeolite modified with NaHCO 3 was dispersed well in the membrane surface, thus increasing its membrane efficiency. At the optimum preparation condition, 0.2 wt% NZ-NaHCO 3 treated using 1 M NaHCO 3 , the TFN NZ-NaHCO 3 exhibited the highest flux of 1,869 g∙m2∙h−1 with 99% water concentration in permeate. Furthermore, the modified membrane had a stable performance for long-term, as well as at different operating temperature and alcohol concentration in the feed. Therefore, the right concentration and type of alkaline could improve the property of nanozeolite for preparing high pervaporation membrane. [Display omitted] [ABSTRACT FROM AUTHOR]

Background/purpose β-Tricalcium phosphate (β-TCP) is an osteoconductive material. Earlier reports revealed that silica plays an important role in bone mineralization, and its incorporation would enhance the biocompatibility of implants. Materials and methods In this study, silica doping at various concentrations (0 wt.%, 10 wt.%, 20 wt.%, and 30 wt.%) was performed. Si-â-TCP was obtained upon calcining the as-prepared powders at 1400°C. To check its effectiveness, different Si-â-TCP samples were prepared to make new bioactive and biodegradable biocomposites for bone repair. Formation of bonelike apatite, the diametral tensile strength, ions released, and weight loss of composites were considered before and after immersion in simulated body fluid. We also examined the behavior of human dental pulp cells (hDPCs) cultured on these materials. Results The results showed that the apatite deposition ability of the β-TCP was enhanced as the Si content was increased. For composites with >20% Si content, the apatite layer covered the samples. At the end of the immersion point, weight losses of 52%, 45%, 33%, and 26% were observed for the β-TCP containing 0%, 10%, 20%, and 30% Si, respectively. In vitro cell experiments showed that the Si-rich cement promotes hDPC proliferation and differentiation. However, when the Si content in the cement is >20%, the amount of cells and osteogenesis protein of hDPCs were stimulated by Si released from Si-β-TCP. Conclusion The degradation of β-TCP and osteogenesis of Si give us a strong reason to believe that these Si-based cements may prove to be promising bone repair materials. [ABSTRACT FROM AUTHOR]

Carbon dioxide-enriched air can be used to promote the photosynthesis of plants, accelerate plant growth and fix more carbon dioxide which means that it can solve the food crisis and the greenhouse effect at the same time. The carbon dioxide-enriched air permeance and CO 2 concentration in the permeate of the membrane must reach 2000 GPU and 800 ppm to meet the practical needs of accelerating the growth of plants. A polydimethylsiloxane (PDMS)/polysulfone (PSf) composite membrane with appropriate modification that can meet the set goals was successfully prepared. The structure of the membrane selective layer can be precisely adjusted by comprehensively surveying the thickness of the selective layer, the amount of crosslinking agent added, the UV/O 3 treatment time and the heat treatment. The carbon dioxide-enriched air permeance and CO 2 concentration in the permeate of the modified PDMS/PSf composite membrane reached 2336 GPU and 814 ppm, respectively. In this work, the prepared membrane was also applied to cultivate plants. Comparing Glebionis coronaria grown in an atmospheric environment with Glebionis coronaria grown in CO 2 -enriched air, the plant mass and plant height increased by 240% and 40%, respectively, after 4 weeks of growth. Experimental results show that the development of carbon dioxide-enriched PDMS/PSf-modified membranes has strong potential to capture CO 2 and accelerate the food production. [Display omitted] • Modification of the active layer of PDMS membrane using various techniques. • To see the impact of CO 2 enrichment on plants grown in CO 2 -enriched and regular air. • The integrated system resulted in reduced greenhouse gas emissions and faster plant growth. [ABSTRACT FROM AUTHOR]

• Surface of polyamide TFC tubular membrane was modified using PEG-GA. • PEG-GA enhanced membrane hydrophilicity and surface negatively charged. • Modification using PEG-GA onto the TFC membrane improves separation efficiency. • PEG-GA-TFC membrane delivered good antifouling property. Membrane fouling can deteriorate the membrane performance for the long term. Surface modification of the membrane using hydrophilic moieties improves the antifouling property of the membrane. In this study, thin-film composite (TFC) polyamide tubular membrane was modified using glutaraldehyde (GA) and polyethylene glycol (PEG). Polyamide layer was formed through interfacial polymerization of piperazine (PIP) with trimesoyl chloride (TMC). Before modification using PEG on the surface of the TFC membrane, the TFC membrane was post-treated using GA. The aldehyde group of the GA reacted with free amines on the polyamide surface, producing enamine. PEG modified the GA-TFC membrane through the reaction of excess aldehyde group of the GA on the membrane surface. PEG-GA-TFC membrane shows a better hydrophilicity and membrane surface charge than pristine and GA-TFC membrane. Consequently, during nanofiltration test, it delivered the highest membrane performance and antifouling property (tested using 100 ppm BSA solution). Furthermore, the modified membrane exhibited good stability in a wide range of pressure and salt concentration. [Display omitted] [ABSTRACT FROM AUTHOR]