Blending Process Research Articles

Experimental analysis of surface integrity in electro-discharge coating process

Utilising electro-discharge machining, powdered metallurgical tool materials are applied to coat the surface pattern-wise. The tool undergoes a thorough blending process followed by hydraulic pellet press. Essential evaluations encompass the determination of material deposition rate, tool wear rate, surface roughness, microhardness, layer thickness and wear rate. Characterisations confirm the presence of tool constituents, provide insights into its constituent's composition and reveal the formation of tungsten carbides on the uppermost surface of the deposit. Significantly, a substantially higher deposition rate of 4.9 mg/min is achieved when a compact load of 10 tons and a peak current of 2.5A are applied. Notably, the top surface exhibits a microhardness of 330.5 HV, while the base material maintains a hardness level of 98.7 HV. The maximum thickness of the deposited layer reaches 293.68 μm under identical conditions. These hard materials serve to mitigate the specific wear rate effectively.

The Impact of Chitosan Incorporation on the Mechanical Characteristics of Biodegradable Packaging based on PLA/PCL Blend

The development of environmentally sustainable plastics has gained prominence due to their eco-friendliness and renewable nature. In this research, eco-friendly plastic was formulated by blending Polylactic Acid (PLA) and Polycaprolactone (PCL) with the incorporation of chitosan as a filler. The primary objective of this study is to scrutinize and delineate the influence of varying compositions of PLA/PCL/chitosan on the mechanical attributes of eco-friendly plastics. This was achieved through hot pressing methods at a temperature of 200°C for a duration of 1 hour. The composition ratios for PLA/PCL were set at 2/8 g, 3/7 g, 5/5 g, 7/3 g, and 8/2 g, while chitosan compositions ranged from 0.2 g to 0.6 g. Comprehensive assessment of the eco-friendly plastics involved biodegradability tests, tensile strength measurements, elongation evaluations, functional group analyses, and examination of plastic film morphology. Optimal performance, ascertained through characterization, was achieved with a composition of PLA/PCL/Chitosan at 8/2/0.6 g, yielding a 38.8% degradation rate, a tensile strength of 42.53 MPa with a composition of PLA/PCL/Chitosan at 8/2/0.4 g, and an elongation of 6.96% with a composition of PLA/PCL/Chitosan at 8/2/0.2 g. The functional groups identified included N-H, C-H, C=O, and C-O groups, indicating a blending process without the formation of new functional groups. Morphology testing revealed a smooth surface, although some undissolved chitosan particles were evident, likely due to non-uniform blending.

Does a blended learning implementation package enhance HIV index case testing in Malawi? A protocol for a cluster randomised controlled trial

IntroductionIndex case testing (ICT) is an evidence-based approach that efficiently identifies persons in need of HIV treatment and prevention services. In Malawi, delivery of ICT has faced challenges due to...

Investigation on mechanical, electrical and morphological of high-density polyethylene (HDPE) reinforced with different particle size and composition of graphene nanoplatelets (GNP)

Graphene nanoplatelets (GNP) are just one of the attractive graphene-based nanomaterials that are rapidly emerging and have sparked the interest of many industries. These small stacks of platelet-shaped graphene sheets have a unique size and morphology that quickly disperse into other materials such as polymers, resulting in higher-value composite materials with improved thermal, conductivity, and mechanical capabilities. A detailed analysis of reinforced High-Density Polyethylene (HDPE) using different sizes (2, 15, 25 µm) and compositions (8, 10, 15 wt.%) of Graphene Nanoplatelets (GNP) has been conducted. The microstructure of the HDPE/GNP nanocomposites was extensively examined during the melt blending and injection moulding processes. Based on the results, the nanocomposites with different sizes of GNP exhibited dissimilar behaviour with different compositions. Furthermore, scanning electron microscope (SEM) results indicated a homogeneous dispersion for GNP in melt mixing. Moreover, thermogravimetric (TG) data demonstrate that increasing filler showed a slight increase in the material's thermal stability. The use of GNP improved mechanical properties, as evidenced by the increases in Young's modulus of yield strength from around 100 MPa to over 400 MPa. This study provides a practical reference for the industrial preparation of polymer-based graphene nanocomposites.

Nursing Undergraduate Students' Experiences and Perceptions of Blended Learning in Pediatric Nursing: A Mixed Methods Study.

Blended learning is a teaching approach that integrates online self-learning and classroom teaching. It emphasizes students' self-directed learning, actively engaging, as well as communication and collaboration. Blended learning develops the qualities in nursing undergraduate students with problem-solving ability, clinical thinking, and communication skills as nurses have. Currently, learners' experience has become an important factor in determining the success of blended learning. To learn about the experiences and perceptions of undergraduate nursing students regarding blending learning in pediatric nursing. A mixed methods design beginning with a quantitative data collection and analysis phase to inform the subsequent qualitative phase was utilized. This study was conducted among undergraduate nursing students at one university in China. In the quantitative study phase, a convenience sample of 59 students completed the online survey while the qualitative study phase included nine students recruited by purposive sampling. The qualitative data were collected using individual semistructured in-depth interviews. Audio data were transcribed and subjected to thematic analysis. The findings from those two phases were integrated into the final analysis. The majority (89.8%) of students reported satisfaction with blended learning. Among various teaching methods, case-based learning (CBL) was the most preferred (98.3%). Regarding the qualitative data, students reported positive experiences with blended learning including well-organized course structure, resourceful course content, and high teacher quality. They stated that blended learning improved the learning outcomes such as improving problem-solving ability and developing clinical thinking. They also provided suggestions for achieving better learning outcomes, including providing stressful learning activities, optimizing online course design, and improving the quality of group learning. The blended learning model of pediatric nursing based on the Community of Inquiry framework provides a positive learning experience for nursing undergraduate students. However, ongoing assessment and improvement of the blended learning process are also needed.

Escalating the use of jute (Robi-1)-cotton blended yarn rather than entirely made of cotton yarn

The process of blending involves the mixing of two different fibers to achieve the desired percentage. Various compositions, lengths, diameters, or colors may be intermingling to produce a blended yarn in a ring spinning system. This system entails the combination of different fibers lots into a homogeneous mass before spinning the mass into a staple fiber yarn. Typically, BJRI Tossa Pat-8 (Robi-1) and cotton fibers are combined to create jute-cotton blended yarn. Jute can be utilized in various ways, which is one approach to blending yarn. The jute-cotton blended yarn was produced in a ratio of 30% and 70%. Both jute-cotton blended yarn and totally cotton yarn were produced on a cotton spinning line using a ring frame. The physical characteristics of both yarns, such as count, yarn Lea strength, and CSP were measured. The average count of fully cotton yarn and jute-cotton blended yarn was found to be roughly equal at 12.16 and 11.82, respectively. However, the yarn lea strength and CSP of both samples, which are significantly different from one another, were 232 lb, 140 lb, and 2835, 1670, respectively. Along with entirely made of yarn, blended yarn also exhibits consistency in terms of CV%, SD, and PMD. This study compared the physical characteristics of both yarns after Robi-1 was first introduced for the blending process with cotton to produce a jute-cotton blended yarn.

Optimizing the mixing formulas of cordyceps tea: Using sensory method and testing harmful microorganism

This study aimed to develop a raw material blending process and evaluate the sensory characteristics of an herbal tea mixture containing Cordyceps militaris in combination with pineapple (Ananas comosus), ginger (Zingiber officinale(Willd.)), lemongrass (Cymbopogon citratus), and chrysanthemum (Chrysanthemum indicum). The research showed no presence (negative) of harmful microorganisms and quantities that could affect consumers in two consecutive tests. The sterilization and raw material blending process met the food safety standards (TCVN). The sensory evaluation results from consumers identified two mixed herbal (NT2 and NT5) tea formulations that received the highest ratings (7.730 and 8.040 points, respectively) and they were significantly higher than the remaining formulations while being not significantly different from each other, indicated that researchers can select suitable raw materials and blending ratios for large-scale production.

The Effect of Composition and Structure of NBR-Based Elastomer Blends in the Vulcanization Process and Study of Their Aging by Exposure to Heat and Radiation

The vulcanization process of elastomeric blends based on chlorinated aromatic nitrile-butadiene rubber (SKN-40M) has been studied in the present work. The structural parameters (molecular weight, plasticity, rigidity, number of network chains, cross-linked molecules) in thermovulcanizates were investigated on an example of nitrile-butadiene rubber blend with polyvinyl chloride using viscometry and the sol-gel process.

Pro dan Kontra dalam Perkuliahan Secara Blended Learning di Program studi Pendidikan Matematika UNU Pasuruan Tahun 2023

Blended learning is a new learning strategy that provides many benefits for students, as well as a form of information and communication technology support towards new learning modes. This research aims to find out: 1) The pros and cons of blended learning lectures in the UNU Pasuruan mathematics education study program in 2023. 2) supporting and inhibiting factors for the blended learning lecture process. This type of research is qualitative with a descriptive approach. The number of samples in this study was 6. The data collection technique was to include the results of interviews that had been conducted accompanied by documentation of their implementation.

Using Blended Disaster Learning Multimedia (BDLM) for Geography Teachers Candidate: Experimental Study on Disaster Preparedness Knowledge

Blended learning needs supporting components to be able to achieve learning objectives. The use of Blended Disaster Learning Multimedia (BDLM) is used as teaching material to support the blended learning process. The purpose of this study was to determine the effect of using BDLM on knowledge of disaster preparedness. We used a quasi-experimental design using a pretest posttest non-equivalent control group design. Data were analyzed using ANCOVA. Research participants were prospective geography teachers who are participating in the lecture program in the 2021/2022 academic year. To assess the knowledge of disaster preparedness using an essay test that is adapted to disaster preparedness indicators. The results show that BDLM integrated blended learning has an effect on knowledge of disaster preparedness. The experimental group appears to have superior knowledge of disaster preparedness with superiority in all indicators of knowledge of disaster preparedness. There is no significant effect between gender differences, because the treatment does not discriminate between gender. The interaction between BDLM learning and gender has a significant effect due to BDLM is a medium that focuses on learning activities not on the treatment of gender differences. The perceived impact is that using BDLM can increase disaster preparedness knowledge. Therefore it is necessary to apply it to prospective geography teachers more broadly.

Effect of Polyvinylpyrrolidone on the Structure Development, Electrical, Thermal, and Wetting Properties of Polyvinylidene Fluoride-Expanded Graphite Nanocomposites.

Polyvinylidene fluoride (PVDF)-expanded graphite (ExGr) nanocomposites have been prepared by solution blending and melt processing methods. In the presence of polyvinylpyrrolidone (PVP), enhanced dispersion of graphite nanosheets (GNSs) in the PVDF matrix, as suggested by field emission scanning electron microscopy analysis, results in very low electrical percolation threshold (0.3 wt % ExGr). X-ray diffraction, Fourier transform infrared spectroscopy, and differential scanning calorimetry (DSC) analyses confirm the coexistence of electroactive gamma and nonpolar alpha phases. Wrapping of PVP chains around GNSs reduces the crystallinity in PVDF-ExGr nanocomposites in comparison to that in neat PVDF films, as evidenced by DSC analysis. Thermogravimetric analysis confirms enhanced thermal stability of PVDF-ExGr nanocomposites above 500 °C mainly attributed to the PVP-assisted dispersion of GNSs. The water contact angle of solution-blended PVDF-ExGr nanocomposite films increases with and without PVP in comparison to that of the neat PVDF film. Compression-molded PVDF-ExGr nanocomposites also exhibit electroactive gamma and nonpolar alpha phases of PVDF with reduction in electrical conductivity compared to solvent-cast films.

Preparation of ionic liquid modified graphene and its effect on enhancing the properties of PA6 composites

AbstractIn this study, an ionic liquid (IL) with imidazole and amide groups has been prepared, and used to modify graphene (TSG) by ball milling to fabricate ionic liquid functional graphene (TSG‐IL). During the melt blending process, TSG‐IL forms hydrogen bond with the amide group of PA6, which destroys the hydrogen bond of PA6 itself, enhances the interfacial force between TSG‐IL and PA6 matrix, and improves the dispersion of TSG‐IL in PA6 matrix. There has been some improvement in the mechanical and thermal conductivity of PA6 composites. Additionally, the presence of amide groups makes it easy to form hydrogen bonds between TSG‐IL sheets, thus strengthening the connection between TSG‐IL and each other, which is conducive to the construction of thermal conductivity network. The findings indicate that compares to TSG/PA6 composites with the same filler amount, the TSG‐IL/PA6 composites have better heat conductivity and higher mechanical characteristics. 9 wt.% TSG‐IL/PA6 composite has the highest thermal conductivity (0.498 W·m−1·k−1), which is 92.3% and 17.2% greater than that of pure PA6 and 9 wt.% TSG/PA6, and its impact strength (11.12 kJ/m2) is 11.0% and 7% higher, which would be a popular candidate material in the field of thermal conductivity.Highlights Imidazole ionic liquids with amide groups was synthesized. Amide groups were modified onto graphene sheets by ball‐milling. The dispersion of TSG‐IL in PA6 was studied. Improved mechanical property and thermal conductivity of TSG‐IL/PA6 composites.

A Cognitive Interpretation of Annie of Green Gables from the Perspective of Conceptual Blending Theory

Translation of children’s literature has always been an important part of the study of translated works. From the perspective of conceptual blending, translation is a dynamic cognitive process involving multiple interactions among the translator, source language author and target language reader, and simultaneously binding and creative unity. Different from adult literature, children’s literature has its own particularity, so we should pay attention to translation methods and means. Based on conceptual blending theory, this thesis uses the theoretical research method and case analysis method to interpret the two processes of the cultural blending of the source text and the source text and the target language in Ma Ainong’s translation of Anne of Green Gables. In the process of blending, the translator projects some elements of the original text space and the target language space into the target language space, connecting the interaction between the source language author and the target language reader and activating the cultural cognitive framework of the target language reader. Conceptual blending theory provides a new cognitive perspective for the interpretation of children’s literature translation.

Optimization of Feed Blending Process for Copper Smelter

Optimization of Feed Blending Process for Copper Smelter

From racialized brands to authentic brands: Dynamic conceptual blending

ABSTRACT Our primary objective for this study is to examine how racialization can shift along the continuum to authenticity that is also sustainable. A subordinate objective is to examine the conceptual blending process that occurs when racialized brands are shifted to sustainable authentic brands. We review the foundation of our research. This includes existing approaches to diversity, equity, and inclusion and conceptual blending. Our methodology is ethnography and The Zaltman Metaphor Elicitation Technique (ZMET). Using the visual metaphors of 8 artrepeneurs from racialized populations we conclude that sustainable authenticity is a construct that emerges with four themes: unleashing resources, environmental sustainability, emotional transparency, and beauty in diversity. Theoretical and managerial implications are provided.

Optimization and analysis of Sic reinforced copolymer blend composite structural springs

The design of lightweight leaf springs plays a crucial role in reducing fuel consumption and improving vehicle comfort by minimizing road shock transmission and vibration. Composite materials have shown great potential in significantly reducing leaf spring weight. epoxy, being a desirable thermoset polymer widely used in various applications such as electrical devices, ships and automobiles, exhibits limitations in terms of brittleness, fracture resistance and impact strength. To overcome these drawbacks while preserving its beneficial properties, epoxy can be blended with other polymers and reinforcements. In this study, polysulfide (PS) was selected as a suitable solution to enhance epoxy brittleness, offering an effective yet underutilized approach. Furthermore, the incorporation of silicon carbide (Sic), known for its superior characteristics, aimed to further enhance the mechanical properties of the epoxy-PS copolymer blend. The microstructural analysis was inspected using Fourier transform infrared. The blending and reinforcement process followed a Taguchi L8 static design to evaluate the impact of different composite blending percentages (represented as input factors) on leaf spring tensile strength, damping properties, impact resistance and hardness (represented as responses). The responses were analyzed using S/N ratios, ANOVA, main effect plots and interaction plots, while regression equations were employed to predict the responses under varying factors. The analysis demonstrated a robust model for manufacturing leaf springs. Experimental results indicated a 7.4% reduction in hardness with the addition of PS polymer. Conversely, reinforcing the epoxy-PS copolymer with 10–20% wt. of Sic resulted in a 3–5% increase in hardness. The natural frequency of the composite exhibited a gradual decrease upon the incorporation of PS and Sic. Evaluating the damping ratio revealed that the maximum value was achieved when the epoxy-PS copolymer was reinforced with 20% Sic. Additionally, while the copolymer blend displayed the greatest logarithmic decrement, epoxy exhibited the highest damping frequency.

Electromagnetic interference shielding performance of lanthanum ferrite with MWCNT and graphene in the polyethylene polymer matrix in X-band frequency

In the present study, a combination of Lanthanum ferrite (LaFeO3) magnetic nanoparticles with multi-walled carbon nanotubes (MWCNT) and graphene nanoplatelets (GNP) was prepared and used as conducting filler. As prepared Nanofillers were incorporated with the Low-density polyethylene (LDPE) with the melt blending process. The polymer composite was used to study the electromagnetic interference (EMI) shielding behaviour from 8.2 to 12.4 GHz. The electromagnetic (EM) wave shielding was ascribed to the dielectric and magnetic loss phenomena by incorporating graphene, MWCNT, and LaFeO3. The maximum shielding effectiveness of 33.57 dB was obtained with the critical concentration of 50:5:40:5 wt% sample.

Synthesis and fabrication of lightweight microcellular thermoplastic polyimide foams using supercritical CO2 foaming

Polyimide foams (PIFs) are usually synthesized by solution polymerization, followed by chemical foaming to prepare thermosetting foam. In this research, lightweight microcellular thermoplastic polyimide foams (TPIFs) were fabricated via a novel two-step foaming approach using supercritical carbon dioxide (scCO2) as a blowing agent. The poly(amic acid) (PAA) and polyester ammonium salt (PEAS) precursor solutions were synthesized with pyromellitic dianhydride (PMDA) as dianhydride reagents and polyether amine Jeffamine D230 as aliphatic diamine reagent via blending and solution polymerization, respectively. The solution polymerization process demonstrated a higher molecular weight and superior formability than the blending process. The optimum thermal imidization temperature of 200 °C was optimized via the thermal and rheological property analysis. The cell morphology and mechanical properties of the TPIFs could be turned by varying the saturation time, foaming pressure, and imidization temperature. At a thermal imidization temperature of 200 °C, the TPIFs exhibited a branched structure with a small mean cell diameter (123.78 μm), and a high compressive strength (0.4 MPa) under 10 % strain at high temperature and pressure, which was more than ten times that of the TPIFs with thermal imidization temperature of 130 °C. This research provides a feasible method for producing high volume expansion ratio TPIFs with adjustable microcellular structures and outstanding mechanical properties.

Boron nitride nanosheet @ quantum‐sized diamond nanocrystal complex/epoxy nanocomposites with enhancing thermal conductivity and sufficient dielectric breakdown strength

AbstractWith the development of high‐voltage and high‐power devices in the direction of compactness, lightness and extreme working environments, the contradiction between thermal conductivity and dielectric breakdown strength is becoming more and more obvious. In this work, a novel boron nitride nanosheet with uniformly dispersed diamond nanocrystalline (abbreviated as BA@DN) was prepared via facile acidizing hydroxylation, in situ copolymerization self‐assembly of dopamine and blending process. The obtained hybrid filler was employed to embed into epoxy matrix, showing enhanced thermal conductivity and sufficient dielectric breakdown strength. For example, the through‐plane and in‐plane thermal conductivity of epoxy composite with 5% BA@DN‐2 reaches to 0.56 and 3.824 W/m K, respectively. The study proposes a modified plane thermal conductivity model. Based on calculations, it was found that the modified thermal conductivity of 5% BA@DN‐2 is 3.47 W/m K, which is significantly higher than that of pure EP, specifically 17.35 times higher. These findings are significant in terms of materials science. while its alternating current and direct current dielectric breakdown strength are 48.84 and 136.31 kV/mm, about 85.68% and 99.1% of pure epoxy, respectively. The mechanism of outstanding dielectric breakdown strength was analyzed via dielectric characteristic, partial discharge performance and the theory of quantum size effect. In addition, a modified multi‐core model with a multilevel overlapping interface is presented.Highlights The acidified diamond nanocrystals (DNs) were attached to dopamine‐coated boron nitride nanocrystals by a blending process. The small size effect of DNs allows the epoxy film to have both high thermal conductivity and high insulation properties. A thermal conductivity correction model is proposed to eliminate the effect of graphite layer on the film.

A new method based on TGA/FTIR coupling to quantify the different thermal degradation steps of EVA/HNT composites prepared by different processing

The aim of the present article is to expose a new method based on TGA-FTIR coupling to quantify the different steps of the thermal degradation of EVA in the presence of HNT. Moreover, this quantification of the thermal degradation was also correlated to the color change. EVA/HNT composites were processed with different processing conditions: solvent casting in THF or melt blending at different temperatures. The HNT fillers content (from 10 wt% up to 30 wt%) and the melt blending temperature (at 130 °C, 150 °C, 170 °C and 190 °C) were varied. The thermal degradation of EVA in the presence of HNT presents three noticeable steps as evidenced by TG analysis: i) P1, which was identified as the catalytic degradation of vinyl acetate (VA) part of EVA occurring during the heating ramp (around 250 °C), ii) P2, which is the main degradation of VA (around 350 °C) and iii) P3, which is the degradation of the polyethylene chain of EVA (around 500 °C). Nevertheless, in the case of melt blended EVA/HNT composites, macroscopic changes (strong smell and browning color) indicate a thermal degradation occurring during the melt blending process, namely P0. FTIR-TGA coupling allows to quantify the contribution of P0, P1 and P2 (thermal degradation of VA units of EVA) using Gram Schmidt curves of released acetic acid gas which are obtained from the COac. band of acetic acid at 1795 cm−1. The contribution of each thermal degradation step of the VA part of EVA (named P0 to P2) was then quantified and reported as A0 to A2, respectively. The blending process (solvent or melt) such as the HNT fillers content and the melt blending temperatures have a significant influence on the EVA thermal degradation catalyzed by HNT. For example, it was shown that the thermal degradation of VA units occurring during the processing of EVA+ 30HNT composite (named A0 and catalyzed by the HNT) was of 40% for melt blending process (at 170 °C), whereas it was close to 0% for solvent casting process. Moreover, the macroscopic changes were evaluated by color measurements and an interesting correlation could be made between A0 and ΔE* which is the total color deviation. When a significant catalytic effect, during the melt process was observed (A0 values higher than 5%), the total color deviation ΔE* was increased linearly with A0. Finally, in order to avoid the catalytic effect of HNT on the EVA thermal degradation, a functionalization strategy has been developed with an organosilane leading to the suppression of P1, the catalytic degradation of VA in TG analyses.